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-rw-r--r--Makefile1
-rw-r--r--hush.c2191
-rw-r--r--sh.c1935
-rw-r--r--shell/hush.c2191
4 files changed, 4383 insertions, 1935 deletions
diff --git a/Makefile b/Makefile
index dcf6bd6..5a62cb0 100644
--- a/Makefile
+++ b/Makefile
@@ -271,6 +271,7 @@ CFLAGS += $(CFLAGS_EXTRA)
all: applet_source_list busybox busybox.links doc
applet_source_list: busybox.sh Config.h
+ if [ ! -L sh.c ] ; then ln -s lash.c sh.c ; fi
(echo -n "APPLET_SOURCES := "; $(SHELL) $^ $(BB_SRC_DIR)) > $@
doc: olddoc
diff --git a/hush.c b/hush.c
new file mode 100644
index 0000000..f2a4ea4
--- /dev/null
+++ b/hush.c
@@ -0,0 +1,2191 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * sh.c -- a prototype Bourne shell grammar parser
+ * Intended to follow the original Thompson and Ritchie
+ * "small and simple is beautiful" philosophy, which
+ * incidentally is a good match to today's BusyBox.
+ *
+ * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
+ *
+ * Credits:
+ * The parser routines proper are all original material, first
+ * written Dec 2000 and Jan 2001 by Larry Doolittle.
+ * The execution engine, the builtins, and much of the underlying
+ * support has been adapted from busybox-0.49pre's lash,
+ * which is Copyright (C) 2000 by Lineo, Inc., and
+ * written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
+ * That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
+ * Erik W. Troan, which they placed in the public domain. I don't know
+ * how much of the Johnson/Troan code has survived the repeated rewrites.
+ * Other credits:
+ * simple_itoa() was lifted from boa-0.93.15
+ * b_addchr() derived from similar w_addchar function in glibc-2.2
+ * setup_redirect(), redirect_opt_num(), and big chunks of main()
+ * and many builtins derived from contributions by Erik Andersen
+ * miscellaneous bugfixes from Matt Kraai
+ *
+ * There are two big (and related) architecture differences between
+ * this parser and the lash parser. One is that this version is
+ * actually designed from the ground up to understand nearly all
+ * of the Bourne grammar. The second, consequential change is that
+ * the parser and input reader have been turned inside out. Now,
+ * the parser is in control, and asks for input as needed. The old
+ * way had the input reader in control, and it asked for parsing to
+ * take place as needed. The new way makes it much easier to properly
+ * handle the recursion implicit in the various substitutions, especially
+ * across continuation lines.
+ *
+ * Bash grammar not implemented: (how many of these were in original sh?)
+ * $@ (those sure look like weird quoting rules)
+ * $_
+ * ! negation operator for pipes
+ * &> and >& redirection of stdout+stderr
+ * Brace Expansion
+ * Tilde Expansion
+ * fancy forms of Parameter Expansion
+ * Arithmetic Expansion
+ * <(list) and >(list) Process Substitution
+ * reserved words: if, then, elif, else, fi, while, until, for,
+ * do, done, case
+ * Here Documents ( << word )
+ * Functions
+ * Major bugs:
+ * job handling woefully incomplete and buggy
+ * reserved word execution woefully incomplete and buggy
+ * incomplete reserved word sequence doesn't request more lines of input
+ * to-do:
+ * port selected bugfixes from post-0.49 busybox lash
+ * finish implementing reserved words
+ * handle children going into background
+ * clean up recognition of null pipes
+ * have builtin_exec set flag to avoid restore_redirects
+ * figure out if "echo foo}" is fixable
+ * check setting of global_argc and global_argv
+ * control-C handling, probably with longjmp
+ * VAR=value prefix for simple commands
+ * follow IFS rules more precisely, including update semantics
+ * write builtin_eval, builtin_ulimit, builtin_umask
+ * figure out what to do with backslash-newline
+ * explain why we use signal instead of sigaction
+ * propagate syntax errors, die on resource errors?
+ * continuation lines, both explicit and implicit - done?
+ * memory leak finding and plugging - done?
+ * more testing, especially quoting rules and redirection
+ * maybe change map[] to use 2-bit entries
+ * (eventually) remove all the printf's
+ * more integration with BusyBox: prompts, cmdedit, applets
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <ctype.h> /* isalpha, isdigit */
+#include <unistd.h> /* getpid */
+#include <stdlib.h> /* getenv, atoi */
+#include <string.h> /* strchr */
+#include <stdio.h> /* popen etc. */
+#include <glob.h> /* glob, of course */
+#include <stdarg.h> /* va_list */
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h> /* should be pretty obvious */
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+
+/* #include <dmalloc.h> */
+/* #define DEBUG_SHELL */
+
+#ifdef BB_VER
+#include "busybox.h"
+#include "cmdedit.h"
+#else
+/* in place of #include "busybox.h"; much of this is indeed
+ * pasted in from the copy of busybox.h in busybox-0.49pre */
+
+#define xrealloc realloc
+#define applet_name "hush"
+#define shell_main main
+
+extern void *xmalloc(size_t size)
+{
+ void *ptr = malloc(size);
+
+ if (!ptr) {
+ fprintf(stderr, "memory_exhausted\n");
+ exit (EXIT_FAILURE);
+ }
+ return ptr;
+}
+
+extern void usage(const char *usage)
+{
+ fprintf(stderr, "Usage: %s\n", usage);
+ exit(EXIT_FAILURE);
+}
+
+static void verror_msg(const char *s, va_list p)
+{
+ fflush(stdout);
+ fprintf(stderr, "%s: ", applet_name);
+ vfprintf(stderr, s, p);
+ fflush(stderr);
+}
+
+extern void error_msg(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ verror_msg(s, p);
+ va_end(p);
+}
+
+extern void error_msg_and_die(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ verror_msg(s, p);
+ va_end(p);
+ exit(EXIT_FAILURE);
+}
+
+static void vperror_msg(const char *s, va_list p)
+{
+ fflush(stdout);
+ fprintf(stderr, "%s: ", applet_name);
+ if (s && *s) {
+ vfprintf(stderr, s, p);
+ fputs(": ", stderr);
+ }
+ fprintf(stderr, "%s\n", strerror(errno));
+ fflush(stderr);
+}
+
+extern void perror_msg(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ vperror_msg(s, p);
+ va_end(p);
+}
+
+extern void perror_msg_and_die(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ vperror_msg(s, p);
+ va_end(p);
+ exit(EXIT_FAILURE);
+}
+
+FILE *xfopen(const char *path, const char *mode)
+{
+ FILE *fp;
+ if ((fp = fopen(path, mode)) == NULL)
+ perror_msg_and_die(path);
+ return fp;
+}
+#endif /* of busybox.h replacement */
+
+typedef enum {
+ REDIRECT_INPUT = 1,
+ REDIRECT_OVERWRITE = 2,
+ REDIRECT_APPEND = 3,
+ REDIRECT_HEREIS = 4,
+ REDIRECT_IO = 5
+} redir_type;
+
+/* The descrip member of this structure is only used to make debugging
+ * output pretty */
+struct {int mode; int default_fd; char *descrip;} redir_table[] = {
+ { 0, 0, "()" },
+ { O_RDONLY, 0, "<" },
+ { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
+ { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
+ { O_RDONLY, -1, "<<" },
+ { O_RDWR, 1, "<>" }
+};
+
+typedef enum {
+ PIPE_SEQ = 1,
+ PIPE_AND = 2,
+ PIPE_OR = 3,
+ PIPE_BG = 4,
+} pipe_style;
+
+/* might eventually control execution */
+typedef enum {
+ RES_NONE = 0,
+ RES_IF = 1,
+ RES_THEN = 2,
+ RES_ELIF = 3,
+ RES_ELSE = 4,
+ RES_FI = 5,
+ RES_FOR = 6,
+ RES_WHILE = 7,
+ RES_UNTIL = 8,
+ RES_DO = 9,
+ RES_DONE = 10,
+ RES_XXXX = 11
+} reserved_style;
+#define FLAG_END (1<<RES_NONE)
+#define FLAG_IF (1<<RES_IF)
+#define FLAG_THEN (1<<RES_THEN)
+#define FLAG_ELIF (1<<RES_ELIF)
+#define FLAG_ELSE (1<<RES_ELSE)
+#define FLAG_FI (1<<RES_FI)
+#define FLAG_FOR (1<<RES_FOR)
+#define FLAG_WHILE (1<<RES_WHILE)
+#define FLAG_UNTIL (1<<RES_UNTIL)
+#define FLAG_DO (1<<RES_DO)
+#define FLAG_DONE (1<<RES_DONE)
+#define FLAG_START (1<<RES_XXXX)
+
+/* This holds pointers to the various results of parsing */
+struct p_context {
+ struct child_prog *child;
+ struct pipe *list_head;
+ struct pipe *pipe;
+ struct redir_struct *pending_redirect;
+ reserved_style w;
+ int old_flag; /* for figuring out valid reserved words */
+ struct p_context *stack;
+ /* How about quoting status? */
+};
+
+struct redir_struct {
+ redir_type type; /* type of redirection */
+ int fd; /* file descriptor being redirected */
+ int dup; /* -1, or file descriptor being duplicated */
+ struct redir_struct *next; /* pointer to the next redirect in the list */
+ glob_t word; /* *word.gl_pathv is the filename */
+};
+
+struct child_prog {
+ pid_t pid; /* 0 if exited */
+ char **argv; /* program name and arguments */
+ struct pipe *group; /* if non-NULL, first in group or subshell */
+ int subshell; /* flag, non-zero if group must be forked */
+ struct redir_struct *redirects; /* I/O redirections */
+ glob_t glob_result; /* result of parameter globbing */
+ int is_stopped; /* is the program currently running? */
+ struct pipe *family; /* pointer back to the child's parent pipe */
+};
+
+struct pipe {
+ int jobid; /* job number */
+ int num_progs; /* total number of programs in job */
+ int running_progs; /* number of programs running */
+ char *text; /* name of job */
+ char *cmdbuf; /* buffer various argv's point into */
+ pid_t pgrp; /* process group ID for the job */
+ struct child_prog *progs; /* array of commands in pipe */
+ struct pipe *next; /* to track background commands */
+ int stopped_progs; /* number of programs alive, but stopped */
+ int job_context; /* bitmask defining current context */
+ pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
+ reserved_style r_mode; /* supports if, for, while, until */
+ struct jobset *job_list;
+};
+
+struct jobset {
+ struct pipe *head; /* head of list of running jobs */
+ struct pipe *fg; /* current foreground job */
+};
+
+struct close_me {
+ int fd;
+ struct close_me *next;
+};
+
+/* globals, connect us to the outside world
+ * the first three support $?, $#, and $1 */
+char **global_argv;
+unsigned int global_argc;
+unsigned int last_return_code;
+extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
+
+/* Variables we export */
+unsigned int shell_context; /* Used in cmdedit.c to reset the
+ * context when someone hits ^C */
+
+/* "globals" within this file */
+static char *ifs=NULL;
+static char map[256];
+static int fake_mode=0;
+static int interactive=0;
+static struct close_me *close_me_head = NULL;
+static char *cwd;
+static struct jobset job_list = { NULL, NULL };
+static unsigned int last_bg_pid=0;
+static char *PS1;
+static char *PS2 = "> ";
+
+#define B_CHUNK (100)
+#define B_NOSPAC 1
+#define MAX_LINE 256 /* for cwd */
+#define MAX_READ 256 /* for builtin_read */
+
+typedef struct {
+ char *data;
+ int length;
+ int maxlen;
+ int quote;
+ int nonnull;
+} o_string;
+#define NULL_O_STRING {NULL,0,0,0,0}
+/* used for initialization:
+ o_string foo = NULL_O_STRING; */
+
+/* I can almost use ordinary FILE *. Is open_memstream() universally
+ * available? Where is it documented? */
+struct in_str {
+ const char *p;
+ int __promptme;
+ int promptmode;
+ FILE *file;
+ int (*get) (struct in_str *);
+ int (*peek) (struct in_str *);
+};
+#define b_getch(input) ((input)->get(input))
+#define b_peek(input) ((input)->peek(input))
+
+#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
+
+struct built_in_command {
+ char *cmd; /* name */
+ char *descr; /* description */
+ int (*function) (struct child_prog *); /* function ptr */
+};
+
+/* belongs in busybox.h */
+static inline int max(int a, int b) {
+ return (a>b)?a:b;
+}
+
+/* This should be in utility.c */
+#ifdef DEBUG_SHELL
+static void debug_printf(const char *format, ...)
+{
+ va_list args;
+ va_start(args, format);
+ vfprintf(stderr, format, args);
+ va_end(args);
+}
+#else
+static void debug_printf(const char *format, ...) { }
+#endif
+#define final_printf debug_printf
+
+void __syntax(char *file, int line) {
+ fprintf(stderr,"syntax error %s:%d\n",file,line);
+}
+#define syntax() __syntax(__FILE__, __LINE__)
+
+/* Index of subroutines: */
+/* function prototypes for builtins */
+static int builtin_cd(struct child_prog *child);
+static int builtin_env(struct child_prog *child);
+static int builtin_exec(struct child_prog *child);
+static int builtin_exit(struct child_prog *child);
+static int builtin_export(struct child_prog *child);
+static int builtin_fg_bg(struct child_prog *child);
+static int builtin_help(struct child_prog *child);
+static int builtin_jobs(struct child_prog *child);
+static int builtin_pwd(struct child_prog *child);
+static int builtin_read(struct child_prog *child);
+static int builtin_shift(struct child_prog *child);
+static int builtin_source(struct child_prog *child);
+static int builtin_ulimit(struct child_prog *child);
+static int builtin_umask(struct child_prog *child);
+static int builtin_unset(struct child_prog *child);
+/* o_string manipulation: */
+static int b_check_space(o_string *o, int len);
+static int b_addchr(o_string *o, int ch);
+static void b_reset(o_string *o);
+static int b_addqchr(o_string *o, int ch, int quote);
+static int b_adduint(o_string *o, unsigned int i);
+/* in_str manipulations: */
+static int static_get(struct in_str *i);
+static int static_peek(struct in_str *i);
+static int file_get(struct in_str *i);
+static int file_peek(struct in_str *i);
+static void setup_file_in_str(struct in_str *i, FILE *f);
+static void setup_string_in_str(struct in_str *i, const char *s);
+/* close_me manipulations: */
+static void mark_open(int fd);
+static void mark_closed(int fd);
+static void close_all();
+/* "run" the final data structures: */
+static char *indenter(int i);
+static int run_list_test(struct pipe *head, int indent);
+static int run_pipe_test(struct pipe *pi, int indent);
+/* really run the final data structures: */
+static int setup_redirects(struct child_prog *prog, int squirrel[]);
+static int pipe_wait(struct pipe *pi);
+static int run_list_real(struct pipe *pi);
+static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
+static int run_pipe_real(struct pipe *pi);
+/* extended glob support: */
+static int globhack(const char *src, int flags, glob_t *pglob);
+static int glob_needed(const char *s);
+static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* data structure manipulation: */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
+static void initialize_context(struct p_context *ctx);
+static int done_word(o_string *dest, struct p_context *ctx);
+static int done_command(struct p_context *ctx);
+static int done_pipe(struct p_context *ctx, pipe_style type);
+/* primary string parsing: */
+static int redirect_dup_num(struct in_str *input);
+static int redirect_opt_num(o_string *o);
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
+static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
+static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src);
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
+static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
+static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
+/* setup: */
+static int parse_stream_outer(struct in_str *inp);
+static int parse_string_outer(const char *s);
+static int parse_file_outer(FILE *f);
+
+/* Table of built-in functions. They can be forked or not, depending on
+ * context: within pipes, they fork. As simple commands, they do not.
+ * When used in non-forking context, they can change global variables
+ * in the parent shell process. If forked, of course they can not.
+ * For example, 'unset foo | whatever' will parse and run, but foo will
+ * still be set at the end. */
+static struct built_in_command bltins[] = {
+ {"bg", "Resume a job in the background", builtin_fg_bg},
+ {"cd", "Change working directory", builtin_cd},
+ {"env", "Print all environment variables", builtin_env},
+ {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec},
+ {"exit", "Exit from shell()", builtin_exit},
+ {"export", "Set environment variable", builtin_export},
+ {"fg", "Bring job into the foreground", builtin_fg_bg},
+ {"jobs", "Lists the active jobs", builtin_jobs},
+ {"pwd", "Print current directory", builtin_pwd},
+ {"read", "Input environment variable", builtin_read},
+ {"shift", "Shift positional parameters", builtin_shift},
+ {"ulimit","Controls resource limits", builtin_ulimit},
+ {"umask","Sets file creation mask", builtin_umask},
+ {"unset", "Unset environment variable", builtin_unset},
+ {".", "Source-in and run commands in a file", builtin_source},
+ {"help", "List shell built-in commands", builtin_help},
+ {NULL, NULL, NULL}
+};
+
+/* built-in 'cd <path>' handler */
+static int builtin_cd(struct child_prog *child)
+{
+ char *newdir;
+ if (child->argv[1] == NULL)
+ newdir = getenv("HOME");
+ else
+ newdir = child->argv[1];
+ if (chdir(newdir)) {
+ printf("cd: %s: %s\n", newdir, strerror(errno));
+ return EXIT_FAILURE;
+ }
+ getcwd(cwd, sizeof(char)*MAX_LINE);
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'env' handler */
+static int builtin_env(struct child_prog *dummy)
+{
+ char **e = environ;
+ if (e == NULL) return EXIT_FAILURE;
+ for (; *e; e++) {
+ puts(*e);
+ }
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'exec' handler */
+static int builtin_exec(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ return EXIT_SUCCESS; /* Really? */
+ child->argv++;
+ pseudo_exec(child);
+ /* never returns */
+}
+
+/* built-in 'exit' handler */
+static int builtin_exit(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ exit(EXIT_SUCCESS);
+ exit (atoi(child->argv[1]));
+}
+
+/* built-in 'export VAR=value' handler */
+static int builtin_export(struct child_prog *child)
+{
+ int res;
+
+ if (child->argv[1] == NULL) {
+ return (builtin_env(child));
+ }
+ res = putenv(child->argv[1]);
+ if (res)
+ fprintf(stderr, "export: %s\n", strerror(errno));
+ return (res);
+}
+
+/* built-in 'fg' and 'bg' handler */
+static int builtin_fg_bg(struct child_prog *child)
+{
+ int i, jobNum;
+ struct pipe *job=NULL;
+
+ if (!child->argv[1] || child->argv[2]) {
+ error_msg("%s: exactly one argument is expected\n",
+ child->argv[0]);
+ return EXIT_FAILURE;
+ }
+
+ if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
+ error_msg("%s: bad argument '%s'\n",
+ child->argv[0], child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ for (job = child->family->job_list->head; job; job = job->next) {
+ if (job->jobid == jobNum) {
+ break;
+ }
+ }
+
+ if (!job) {
+ error_msg("%s: unknown job %d\n",
+ child->argv[0], jobNum);
+ return EXIT_FAILURE;
+ }
+
+ if (*child->argv[0] == 'f') {
+ /* Make this job the foreground job */
+ /* suppress messages when run from /linuxrc mag@sysgo.de */
+ if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ child->family->job_list->fg = job;
+ }
+
+ /* Restart the processes in the job */
+ for (i = 0; i < job->num_progs; i++)
+ job->progs[i].is_stopped = 0;
+
+ kill(-job->pgrp, SIGCONT);
+
+ job->stopped_progs = 0;
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'help' handler */
+static int builtin_help(struct child_prog *dummy)
+{
+ struct built_in_command *x;
+
+ printf("\nBuilt-in commands:\n");
+ printf("-------------------\n");
+ for (x = bltins; x->cmd; x++) {
+ if (x->descr==NULL)
+ continue;
+ printf("%s\t%s\n", x->cmd, x->descr);
+ }
+ printf("\n\n");
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'jobs' handler */
+static int builtin_jobs(struct child_prog *child)
+{
+ struct pipe *job;
+ char *status_string;
+
+ for (job = child->family->job_list->head; job; job = job->next) {
+ if (job->running_progs == job->stopped_progs)
+ status_string = "Stopped";
+ else
+ status_string = "Running";
+ printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
+ }
+ return EXIT_SUCCESS;
+}
+
+
+/* built-in 'pwd' handler */
+static int builtin_pwd(struct child_prog *dummy)
+{
+ getcwd(cwd, MAX_LINE);
+ puts(cwd);
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'read VAR' handler */
+static int builtin_read(struct child_prog *child)
+{
+ int res = 0, len, newlen;
+ char *s;
+ char string[MAX_READ];
+
+ if (child->argv[1]) {
+ /* argument (VAR) given: put "VAR=" into buffer */
+ strcpy(string, child->argv[1]);
+ len = strlen(string);
+ string[len++] = '=';
+ string[len] = '\0';
+ /* XXX would it be better to go through in_str? */
+ fgets(&string[len], sizeof(string) - len, stdin); /* read string */
+ newlen = strlen(string);
+ if(newlen > len)
+ string[--newlen] = '\0'; /* chomp trailing newline */
+ /*
+ ** string should now contain "VAR=<value>"
+ ** copy it (putenv() won't do that, so we must make sure
+ ** the string resides in a static buffer!)
+ */
+ res = -1;
+ if((s = strdup(string)))
+ res = putenv(s);
+ if (res)
+ fprintf(stderr, "read: %s\n", strerror(errno));
+ }
+ else
+ fgets(string, sizeof(string), stdin);
+
+ return (res);
+}
+
+/* Built-in 'shift' handler */
+static int builtin_shift(struct child_prog *child)
+{
+ int n=1;
+ if (child->argv[1]) {
+ n=atoi(child->argv[1]);
+ }
+ if (n>=0 && n<global_argc) {
+ /* XXX This probably breaks $0 */
+ global_argc -= n;
+ global_argv += n;
+ return EXIT_SUCCESS;
+ } else {
+ return EXIT_FAILURE;
+ }
+}
+
+/* Built-in '.' handler (read-in and execute commands from file) */
+static int builtin_source(struct child_prog *child)
+{
+ FILE *input;
+ int status;
+
+ if (child->argv[1] == NULL)
+ return EXIT_FAILURE;
+
+ /* XXX search through $PATH is missing */
+ input = fopen(child->argv[1], "r");
+ if (!input) {
+ fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ /* Now run the file */
+ /* XXX argv and argc are broken; need to save old global_argv
+ * (pointer only is OK!) on this stack frame,
+ * set global_argv=child->argv+1, recurse, and restore. */
+ mark_open(fileno(input));
+ status = parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ return (status);
+}
+
+static int builtin_ulimit(struct child_prog *child)
+{
+ printf("builtin_ulimit not written\n");
+ return EXIT_FAILURE;
+}
+
+static int builtin_umask(struct child_prog *child)
+{
+ printf("builtin_umask not written\n");
+ return EXIT_FAILURE;
+}
+
+/* built-in 'unset VAR' handler */
+static int builtin_unset(struct child_prog *child)
+{
+ if (child->argv[1] == NULL) {
+ fprintf(stderr, "unset: parameter required.\n");
+ return EXIT_FAILURE;
+ }
+ unsetenv(child->argv[1]);
+ return EXIT_SUCCESS;
+}
+
+static int b_check_space(o_string *o, int len)
+{
+ /* It would be easy to drop a more restrictive policy
+ * in here, such as setting a maximum string length */
+ if (o->length + len > o->maxlen) {
+ char *old_data = o->data;
+ /* assert (data == NULL || o->maxlen != 0); */
+ o->maxlen += max(2*len, B_CHUNK);
+ o->data = realloc(o->data, 1 + o->maxlen);
+ if (o->data == NULL) {
+ free(old_data);
+ }
+ }
+ return o->data == NULL;
+}
+
+static int b_addchr(o_string *o, int ch)
+{
+ debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
+ if (b_check_space(o, 1)) return B_NOSPAC;
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+ return 0;
+}
+
+static void b_reset(o_string *o)
+{
+ o->length = 0;
+ o->nonnull = 0;
+ if (o->data != NULL) *o->data = '\0';
+}
+
+static void b_free(o_string *o)
+{
+ b_reset(o);
+ if (o->data != NULL) free(o->data);
+ o->data = NULL;
+ o->maxlen = 0;
+}
+
+/* My analysis of quoting semantics tells me that state information
+ * is associated with a destination, not a source.
+ */
+static int b_addqchr(o_string *o, int ch, int quote)
+{
+ if (quote && strchr("*?[\\",ch)) {
+ int rc;
+ rc = b_addchr(o, '\\');
+ if (rc) return rc;
+ }
+ return b_addchr(o, ch);
+}
+
+/* belongs in utility.c */
+char *simple_itoa(unsigned int i)
+{
+ /* 21 digits plus null terminator, good for 64-bit or smaller ints */
+ static char local[22];
+ char *p = &local[21];
+ *p-- = '\0';
+ do {
+ *p-- = '0' + i % 10;
+ i /= 10;
+ } while (i > 0);
+ return p + 1;
+}
+
+static int b_adduint(o_string *o, unsigned int i)
+{
+ int r;
+ char *p = simple_itoa(i);
+ /* no escape checking necessary */
+ do r=b_addchr(o, *p++); while (r==0 && *p);
+ return r;
+}
+
+static int static_get(struct in_str *i)
+{
+ int ch=*i->p++;
+ if (ch=='\0') return EOF;
+ return ch;
+}
+
+static int static_peek(struct in_str *i)
+{
+ return *i->p;
+}
+
+static inline void cmdedit_set_initial_prompt(void)
+{
+#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+ PS1 = NULL;
+#else
+ PS1 = getenv("PS1");
+ if(PS1==0)
+ PS1 = "\\w \\$ ";
+#endif
+}
+
+static inline void setup_prompt_string(int promptmode, char **prompt_str)
+{
+#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+ /* Set up the prompt */
+ if (promptmode == 1) {
+ if (PS1)
+ free(PS1);
+ PS1=xmalloc(strlen(cwd)+4);
+ sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
+ *prompt_str = PS1;
+ } else {
+ *prompt_str = PS2;
+ }
+#else
+ *prompt_str = (promptmode==0)? PS1 : PS2;
+#endif
+}
+
+static void get_user_input(struct in_str *i)
+{
+ char *prompt_str;
+ static char the_command[MAX_LINE];
+
+ setup_prompt_string(i->promptmode, &prompt_str);
+#ifdef BB_FEATURE_COMMAND_EDITING
+ /*
+ ** enable command line editing only while a command line
+ ** is actually being read; otherwise, we'll end up bequeathing
+ ** atexit() handlers and other unwanted stuff to our
+ ** child processes (rob@sysgo.de)
+ */
+ cmdedit_read_input(prompt_str, the_command);
+ cmdedit_terminate();
+#else
+ fputs(prompt_str, stdout);
+ fflush(stdout);
+ the_command[0]=fgetc(i->file);
+ the_command[1]='\0';
+#endif
+ i->p = the_command;
+}
+
+/* This is the magic location that prints prompts
+ * and gets data back from the user */
+static int file_get(struct in_str *i)
+{
+ int ch;
+
+ ch = 0;
+ /* If there is data waiting, eat it up */
+ if (i->p && *i->p) {
+ ch=*i->p++;
+ } else {
+ /* need to double check i->file because we might be doing something
+ * more complicated by now, like sourcing or substituting. */
+ if (i->__promptme && interactive && i->file == stdin) {
+ get_user_input(i);
+ i->promptmode=2;
+ }
+ i->__promptme = 0;
+
+ if (i->p && *i->p) {
+ ch=*i->p++;
+ }
+ debug_printf("b_getch: got a %d\n", ch);
+ }
+ if (ch == '\n') i->__promptme=1;
+ return ch;
+}
+
+/* All the callers guarantee this routine will never be
+ * used right after a newline, so prompting is not needed.
+ */
+static int file_peek(struct in_str *i)
+{
+ if (i->p && *i->p) {
+ return *i->p;
+ } else {
+ static char buffer;
+ buffer = fgetc(i->file);
+ i->p = &buffer;
+ debug_printf("b_peek: got a %d\n", *i->p);
+ return *i->p;
+ }
+}
+
+static void setup_file_in_str(struct in_str *i, FILE *f)
+{
+ i->peek = file_peek;
+ i->get = file_get;
+ i->__promptme=1;
+ i->promptmode=1;
+ i->file = f;
+ i->p = NULL;
+}
+
+static void setup_string_in_str(struct in_str *i, const char *s)
+{
+ i->peek = static_peek;
+ i->get = static_get;
+ i->__promptme=1;
+ i->promptmode=1;
+ i->p = s;
+}
+
+static void mark_open(int fd)
+{
+ struct close_me *new = xmalloc(sizeof(struct close_me));
+ new->fd = fd;
+ new->next = close_me_head;
+ close_me_head = new;
+}
+
+static void mark_closed(int fd)
+{
+ struct close_me *tmp;
+ if (close_me_head == NULL || close_me_head->fd != fd)
+ error_msg_and_die("corrupt close_me");
+ tmp = close_me_head;
+ close_me_head = close_me_head->next;
+ free(tmp);
+}
+
+static void close_all()
+{
+ struct close_me *c;
+ for (c=close_me_head; c; c=c->next) {
+ close(c->fd);
+ }
+ close_me_head = NULL;
+}
+
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct child_prog *prog, int squirrel[])
+{
+ int openfd, mode;
+ struct redir_struct *redir;
+
+ for (redir=prog->redirects; redir; redir=redir->next) {
+ if (redir->dup == -1) {
+ mode=redir_table[redir->type].mode;
+ openfd = open(redir->word.gl_pathv[0], mode, 0666);
+ if (openfd < 0) {
+ /* this could get lost if stderr has been redirected, but
+ bash and ash both lose it as well (though zsh doesn't!) */
+ fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0],
+ strerror(errno));
+ return 1;
+ }
+ } else {
+ openfd = redir->dup;
+ }
+
+ if (openfd != redir->fd) {
+ if (squirrel && redir->fd < 3) {
+ squirrel[redir->fd] = dup(redir->fd);
+ }
+ dup2(openfd, redir->fd);
+ close(openfd);
+ }
+ }
+ return 0;
+}
+
+static void restore_redirects(int squirrel[])
+{
+ int i, fd;
+ for (i=0; i<3; i++) {
+ fd = squirrel[i];
+ if (fd != -1) {
+ /* No error checking. I sure wouldn't know what
+ * to do with an error if I found one! */
+ dup2(fd, i);
+ close(fd);
+ }
+ }
+}
+
+/* XXX this definitely needs some more thought, work, and
+ * cribbing from other shells */
+static int pipe_wait(struct pipe *pi)
+{
+ int rcode=0, i, pid, running, status;
+ running = pi->num_progs;
+ while (running) {
+ pid=waitpid(-1, &status, 0);
+ if (pid < 0) perror_msg_and_die("waitpid");
+ for (i=0; i < pi->num_progs; i++) {
+ if (pi->progs[i].pid == pid) {
+ if (i==pi->num_progs-1) rcode=WEXITSTATUS(status);
+ pi->progs[i].pid = 0;
+ running--;
+ break;
+ }
+ }
+ }
+ return rcode;
+}
+
+/* very simple version for testing */
+static void pseudo_exec(struct child_prog *child)
+{
+ int rcode;
+ struct built_in_command *x;
+ if (child->argv) {
+ /*
+ * Check if the command matches any of the builtins.
+ * Depending on context, this might be redundant. But it's
+ * easier to waste a few CPU cycles than it is to figure out
+ * if this is one of those cases.
+ */
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ debug_printf("builtin exec %s\n", child->argv[0]);
+ exit(x->function(child));
+ }
+ }
+ debug_printf("exec of %s\n",child->argv[0]);
+ execvp(child->argv[0],child->argv);
+ perror("execvp");
+ exit(1);
+ } else if (child->group) {
+ debug_printf("runtime nesting to group\n");
+ interactive=0; /* crucial!!!! */
+ rcode = run_list_real(child->group);
+ /* OK to leak memory by not calling run_list_test,
+ * since this process is about to exit */
+ exit(rcode);
+ } else {
+ /* Can happen. See what bash does with ">foo" by itself. */
+ debug_printf("trying to pseudo_exec null command\n");
+ exit(EXIT_SUCCESS);
+ }
+}
+
+/* run_pipe_real() starts all the jobs, but doesn't wait for anything
+ * to finish. See pipe_wait().
+ *
+ * return code is normally -1, when the caller has to wait for children
+ * to finish to determine the exit status of the pipe. If the pipe
+ * is a simple builtin command, however, the action is done by the
+ * time run_pipe_real returns, and the exit code is provided as the
+ * return value.
+ *
+ * The input of the pipe is always stdin, the output is always
+ * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
+ * because it tries to avoid running the command substitution in
+ * subshell, when that is in fact necessary. The subshell process
+ * now has its stdout directed to the input of the appropriate pipe,
+ * so this routine is noticeably simpler.
+ */
+static int run_pipe_real(struct pipe *pi)
+{
+ int i;
+ int nextin, nextout;
+ int pipefds[2]; /* pipefds[0] is for reading */
+ struct child_prog *child;
+ struct built_in_command *x;
+
+ nextin = 0;
+ pi->pgrp = 0;
+
+ /* Check if this is a simple builtin (not part of a pipe).
+ * Builtins within pipes have to fork anyway, and are handled in
+ * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
+ */
+ if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
+ child = & (pi->progs[0]);
+ if (child->group && ! child->subshell) {
+ int squirrel[] = {-1, -1, -1};
+ int rcode;
+ debug_printf("non-subshell grouping\n");
+ setup_redirects(child, squirrel);
+ /* XXX could we merge code with following builtin case,
+ * by creating a pseudo builtin that calls run_list_real? */
+ rcode = run_list_real(child->group);
+ restore_redirects(squirrel);
+ return rcode;
+ }
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ int squirrel[] = {-1, -1, -1};
+ int rcode;
+ debug_printf("builtin inline %s\n", child->argv[0]);
+ /* XXX setup_redirects acts on file descriptors, not FILEs.
+ * This is perfect for work that comes after exec().
+ * Is it really safe for inline use? Experimentally,
+ * things seem to work with glibc. */
+ setup_redirects(child, squirrel);
+ rcode = x->function(child);
+ restore_redirects(squirrel);
+ return rcode;
+ }
+ }
+ }
+
+ for (i = 0; i < pi->num_progs; i++) {
+ child = & (pi->progs[i]);
+
+ /* pipes are inserted between pairs of commands */
+ if ((i + 1) < pi->num_progs) {
+ if (pipe(pipefds)<0) perror_msg_and_die("pipe");
+ nextout = pipefds[1];
+ } else {
+ nextout=1;
+ pipefds[0] = -1;
+ }
+
+ /* XXX test for failed fork()? */
+ if (!(child->pid = fork())) {
+ close_all();
+
+ if (nextin != 0) {
+ dup2(nextin, 0);
+ close(nextin);
+ }
+ if (nextout != 1) {
+ dup2(nextout, 1);
+ close(nextout);
+ }
+ if (pipefds[0]!=-1) {
+ close(pipefds[0]); /* opposite end of our output pipe */
+ }
+
+ /* Like bash, explicit redirects override pipes,
+ * and the pipe fd is available for dup'ing. */
+ setup_redirects(child,NULL);
+
+ pseudo_exec(child);
+ }
+ if (interactive) {
+ /* Put our child in the process group whose leader is the
+ * first process in this pipe. */
+ if (pi->pgrp==0) {
+ pi->pgrp = child->pid;
+ }
+ /* Don't check for errors. The child may be dead already,
+ * in which case setpgid returns error code EACCES. */
+ setpgid(child->pid, pi->pgrp);
+ }
+ /* In the non-interactive case, do nothing. Leave the children
+ * with the process group that they inherited from us. */
+
+ if (nextin != 0)
+ close(nextin);
+ if (nextout != 1)
+ close(nextout);
+
+ /* If there isn't another process, nextin is garbage
+ but it doesn't matter */
+ nextin = pipefds[0];
+ }
+ return -1;
+}
+
+static int run_list_real(struct pipe *pi)
+{
+ int rcode=0;
+ int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
+ reserved_style rmode=RES_NONE;
+ for (;pi;pi=pi->next) {
+ rmode = pi->r_mode;
+ debug_printf("rmode=%d if_code=%d next_if_code=%d\n", rmode, if_code, next_if_code);
+ if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
+ if (rmode == RES_THEN && if_code) continue;
+ if (rmode == RES_ELSE && !if_code) continue;
+ if (rmode == RES_ELIF && !if_code) continue;
+ if (pi->num_progs == 0) break;
+ rcode = run_pipe_real(pi);
+ if (rcode!=-1) {
+ /* We only ran a builtin: rcode was set by the return value
+ * of run_pipe_real(), and we don't need to wait for anything. */
+ } else if (pi->followup==PIPE_BG) {
+ /* XXX check bash's behavior with nontrivial pipes */
+ /* XXX compute jobid */
+ /* XXX what does bash do with attempts to background builtins? */
+ printf("[%d] %d\n", pi->jobid, pi->pgrp);
+ last_bg_pid = pi->pgrp;
+ rcode = EXIT_SUCCESS;
+ } else {
+ if (interactive) {
+ /* move the new process group into the foreground */
+ /* suppress messages when run from /linuxrc mag@sysgo.de */
+ signal(SIGTTIN, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ rcode = pipe_wait(pi);
+ if (tcsetpgrp(0, getpid()) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ signal(SIGTTIN, SIG_DFL);
+ signal(SIGTTOU, SIG_DFL);
+ } else {
+ rcode = pipe_wait(pi);
+ }
+ }
+ last_return_code=rcode;
+ if ( rmode == RES_IF || rmode == RES_ELIF )
+ next_if_code=rcode; /* can be overwritten a number of times */
+ if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
+ (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
+ return rcode; /* XXX broken if list is part of if/then/else */
+ }
+ return rcode;
+}
+
+/* broken, of course, but OK for testing */
+static char *indenter(int i)
+{
+ static char blanks[]=" ";
+ return &blanks[sizeof(blanks)-i-1];
+}
+
+/* return code is the exit status of the pipe */
+static int run_pipe_test(struct pipe *pi, int indent)
+{
+ char **p;
+ struct child_prog *child;
+ struct redir_struct *r, *rnext;
+ int a, i, ret_code=0;
+ char *ind = indenter(indent);
+ final_printf("%s run pipe: (pid %d)\n",ind,getpid());
+ for (i=0; i<pi->num_progs; i++) {
+ child = &pi->progs[i];
+ final_printf("%s command %d:\n",ind,i);
+ if (child->argv) {
+ for (a=0,p=child->argv; *p; a++,p++) {
+ final_printf("%s argv[%d] = %s\n",ind,a,*p);
+ }
+ globfree(&child->glob_result);
+ child->argv=NULL;
+ } else if (child->group) {
+ final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
+ ret_code = run_list_test(child->group,indent+3);
+ final_printf("%s end group\n",ind);
+ } else {
+ final_printf("%s (nil)\n",ind);
+ }
+ for (r=child->redirects; r; r=rnext) {
+ final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
+ if (r->dup == -1) {
+ final_printf(" %s\n", *r->word.gl_pathv);
+ globfree(&r->word);
+ } else {
+ final_printf("&%d\n", r->dup);
+ }
+ rnext=r->next;
+ free(r);
+ }
+ child->redirects=NULL;
+ }
+ free(pi->progs); /* children are an array, they get freed all at once */
+ pi->progs=NULL;
+ return ret_code;
+}
+
+static int run_list_test(struct pipe *head, int indent)
+{
+ int rcode=0; /* if list has no members */
+ struct pipe *pi, *next;
+ char *ind = indenter(indent);
+ for (pi=head; pi; pi=next) {
+ if (pi->num_progs == 0) break;
+ final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
+ rcode = run_pipe_test(pi, indent);
+ final_printf("%s pipe followup code %d\n", ind, pi->followup);
+ next=pi->next;
+ pi->next=NULL;
+ free(pi);
+ }
+ return rcode;
+}
+
+/* Select which version we will use */
+static int run_list(struct pipe *pi)
+{
+ int rcode=0;
+ if (fake_mode==0) {
+ rcode = run_list_real(pi);
+ }
+ /* run_list_test has the side effect of clearing memory
+ * In the long run that function can be merged with run_list_real,
+ * but doing that now would hobble the debugging effort. */
+ run_list_test(pi,0);
+ return rcode;
+}
+
+/* The API for glob is arguably broken. This routine pushes a non-matching
+ * string into the output structure, removing non-backslashed backslashes.
+ * If someone can prove me wrong, by performing this function within the
+ * original glob(3) api, feel free to rewrite this routine into oblivion.
+ * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
+ * XXX broken if the last character is '\\', check that before calling.
+ */
+static int globhack(const char *src, int flags, glob_t *pglob)
+{
+ int cnt, pathc;
+ const char *s;
+ char *dest;
+ for (cnt=1, s=src; *s; s++) {
+ if (*s == '\\') s++;
+ cnt++;
+ }
+ dest = malloc(cnt);
+ if (!dest) return GLOB_NOSPACE;
+ if (!(flags & GLOB_APPEND)) {
+ pglob->gl_pathv=NULL;
+ pglob->gl_pathc=0;
+ pglob->gl_offs=0;
+ pglob->gl_offs=0;
+ }
+ pathc = ++pglob->gl_pathc;
+ pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
+ if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
+ pglob->gl_pathv[pathc-1]=dest;
+ pglob->gl_pathv[pathc]=NULL;
+ for (s=src; *s; s++, dest++) {
+ if (*s == '\\') s++;
+ *dest = *s;
+ }
+ *dest='\0';
+ return 0;
+}
+
+/* XXX broken if the last character is '\\', check that before calling */
+static int glob_needed(const char *s)
+{
+ for (; *s; s++) {
+ if (*s == '\\') s++;
+ if (strchr("*[?",*s)) return 1;
+ }
+ return 0;
+}
+
+#if 0
+static void globprint(glob_t *pglob)
+{
+ int i;
+ debug_printf("glob_t at %p:\n", pglob);
+ debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
+ pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
+ for (i=0; i<pglob->gl_pathc; i++)
+ debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
+ pglob->gl_pathv[i], pglob->gl_pathv[i]);
+}
+#endif
+
+static int xglob(o_string *dest, int flags, glob_t *pglob)
+{
+ int gr;
+
+ /* short-circuit for null word */
+ /* we can code this better when the debug_printf's are gone */
+ if (dest->length == 0) {
+ if (dest->nonnull) {
+ /* bash man page calls this an "explicit" null */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ } else {
+ return 0;
+ }
+ } else if (glob_needed(dest->data)) {
+ gr = glob(dest->data, flags, NULL, pglob);
+ debug_printf("glob returned %d\n",gr);
+ if (gr == GLOB_NOMATCH) {
+ /* quote removal, or more accurately, backslash removal */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ }
+ } else {
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ }
+ if (gr == GLOB_NOSPACE) {
+ fprintf(stderr,"out of memory during glob\n");
+ exit(1);
+ }
+ if (gr != 0) { /* GLOB_ABORTED ? */
+ fprintf(stderr,"glob(3) error %d\n",gr);
+ }
+ /* globprint(glob_target); */
+ return gr;
+}
+
+/* the src parameter allows us to peek forward to a possible &n syntax
+ * for file descriptor duplication, e.g., "2>&1".
+ * Return code is 0 normally, 1 if a syntax error is detected in src.
+ * Resource errors (in xmalloc) cause the process to exit */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
+ struct in_str *input)
+{
+ struct child_prog *child=ctx->child;
+ struct redir_struct *redir = child->redirects;
+ struct redir_struct *last_redir=NULL;
+
+ /* Create a new redir_struct and drop it onto the end of the linked list */
+ while(redir) {
+ last_redir=redir;
+ redir=redir->next;
+ }
+ redir = xmalloc(sizeof(struct redir_struct));
+ redir->next=NULL;
+ if (last_redir) {
+ last_redir->next=redir;
+ } else {
+ child->redirects=redir;
+ }
+
+ redir->type=style;
+ redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
+
+ debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
+
+ /* Check for a '2>&1' type redirect */
+ redir->dup = redirect_dup_num(input);
+ if (redir->dup == -2) return 1; /* syntax error */
+ if (redir->dup != -1) {
+ /* Erik had a check here that the file descriptor in question
+ * is legit; I postpone that to "run time" */
+ debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
+ } else {
+ /* We do _not_ try to open the file that src points to,
+ * since we need to return and let src be expanded first.
+ * Set ctx->pending_redirect, so we know what to do at the
+ * end of the next parsed word.
+ */
+ ctx->pending_redirect = redir;
+ }
+ return 0;
+}
+
+struct pipe *new_pipe(void) {
+ struct pipe *pi;
+ pi = xmalloc(sizeof(struct pipe));
+ pi->num_progs = 0;
+ pi->progs = NULL;
+ pi->next = NULL;
+ pi->followup = 0; /* invalid */
+ return pi;
+}
+
+static void initialize_context(struct p_context *ctx)
+{
+ ctx->pipe=NULL;
+ ctx->pending_redirect=NULL;
+ ctx->child=NULL;
+ ctx->list_head=new_pipe();
+ ctx->pipe=ctx->list_head;
+ ctx->w=RES_NONE;
+ ctx->stack=NULL;
+ done_command(ctx); /* creates the memory for working child */
+}
+
+/* normal return is 0
+ * if a reserved word is found, and processed, return 1
+ * should handle if, then, elif, else, fi, for, while, until, do, done.
+ * case, function, and select are obnoxious, save those for later.
+ */
+int reserved_word(o_string *dest, struct p_context *ctx)
+{
+ struct reserved_combo {
+ char *literal;
+ int code;
+ long flag;
+ };
+ /* Mostly a list of accepted follow-up reserved words.
+ * FLAG_END means we are done with the sequence, and are ready
+ * to turn the compound list into a command.
+ * FLAG_START means the word must start a new compound list.
+ */
+ static struct reserved_combo reserved_list[] = {
+ { "if", RES_IF, FLAG_THEN | FLAG_START },
+ { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
+ { "elif", RES_ELIF, FLAG_THEN },
+ { "else", RES_ELSE, FLAG_FI },
+ { "fi", RES_FI, FLAG_END },
+ { "for", RES_FOR, FLAG_DO | FLAG_START },
+ { "while", RES_WHILE, FLAG_DO | FLAG_START },
+ { "until", RES_UNTIL, FLAG_DO | FLAG_START },
+ { "do", RES_DO, FLAG_DONE },
+ { "done", RES_DONE, FLAG_END }
+ };
+ struct reserved_combo *r;
+ for (r=reserved_list;
+#define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
+ r<reserved_list+NRES; r++) {
+ if (strcmp(dest->data, r->literal) == 0) {
+ debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
+ if (r->flag & FLAG_START) {
+ struct p_context *new = xmalloc(sizeof(struct p_context));
+ debug_printf("push stack\n");
+ *new = *ctx; /* physical copy */
+ initialize_context(ctx);
+ ctx->stack=new;
+ } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
+ syntax(); /* XXX how do we get out? */
+ }
+ ctx->w=r->code;
+ ctx->old_flag = r->flag;
+ if (ctx->old_flag & FLAG_END) {
+ struct p_context *old;
+ debug_printf("pop stack\n");
+ old = ctx->stack;
+ old->child->group = ctx->list_head;
+ *ctx = *old; /* physical copy */
+ free(old);
+ ctx->w=RES_NONE;
+ }
+ b_reset (dest);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/* normal return is 0.
+ * Syntax or xglob errors return 1. */
+static int done_word(o_string *dest, struct p_context *ctx)
+{
+ struct child_prog *child=ctx->child;
+ glob_t *glob_target;
+ int gr, flags = 0;
+
+ debug_printf("done_word: %s %p\n", dest->data, child);
+ if (dest->length == 0 && !dest->nonnull) {
+ debug_printf(" true null, ignored\n");
+ return 0;
+ }
+ if (ctx->pending_redirect) {
+ glob_target = &ctx->pending_redirect->word;
+ } else {
+ if (child->group) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ if (!child->argv) {
+ debug_printf("checking %s for reserved-ness\n",dest->data);
+ if (reserved_word(dest,ctx)) return 0;
+ }
+ glob_target = &child->glob_result;
+ if (child->argv) flags |= GLOB_APPEND;
+ }
+ gr = xglob(dest, flags, glob_target);
+ if (gr != 0) return 1;
+
+ b_reset(dest);
+ if (ctx->pending_redirect) {
+ ctx->pending_redirect=NULL;
+ if (glob_target->gl_pathc != 1) {
+ fprintf(stderr, "ambiguous redirect\n");
+ return 1;
+ }
+ } else {
+ child->argv = glob_target->gl_pathv;
+ }
+ return 0;
+}
+
+/* The only possible error here is out of memory, in which case
+ * xmalloc exits. */
+static int done_command(struct p_context *ctx)
+{
+ /* The child is really already in the pipe structure, so
+ * advance the pipe counter and make a new, null child.
+ * Only real trickiness here is that the uncommitted
+ * child structure, to which ctx->child points, is not
+ * counted in pi->num_progs. */
+ struct pipe *pi=ctx->pipe;
+ struct child_prog *prog=ctx->child;
+
+ if (prog && prog->group == NULL
+ && prog->argv == NULL
+ && prog->redirects == NULL) {
+ debug_printf("done_command: skipping null command\n");
+ return 0;
+ } else if (prog) {
+ pi->num_progs++;
+ debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
+ } else {
+ debug_printf("done_command: initializing\n");
+ }
+ pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
+
+ prog = pi->progs + pi->num_progs;
+ prog->redirects = NULL;
+ prog->argv = NULL;
+ prog->is_stopped = 0;
+ prog->group = NULL;
+ prog->glob_result.gl_pathv = NULL;
+ prog->family = pi;
+
+ ctx->child=prog;
+ /* but ctx->pipe and ctx->list_head remain unchanged */
+ return 0;
+}
+
+static int done_pipe(struct p_context *ctx, pipe_style type)
+{
+ struct pipe *new_p;
+ done_command(ctx); /* implicit closure of previous command */
+ debug_printf("done_pipe, type %d\n", type);
+ ctx->pipe->followup = type;
+ ctx->pipe->r_mode = ctx->w;
+ new_p=new_pipe();
+ ctx->pipe->next = new_p;
+ ctx->pipe = new_p;
+ ctx->child = NULL;
+ done_command(ctx); /* set up new pipe to accept commands */
+ return 0;
+}
+
+/* peek ahead in the in_str to find out if we have a "&n" construct,
+ * as in "2>&1", that represents duplicating a file descriptor.
+ * returns either -2 (syntax error), -1 (no &), or the number found.
+ */
+static int redirect_dup_num(struct in_str *input)
+{
+ int ch, d=0, ok=0;
+ ch = b_peek(input);
+ if (ch != '&') return -1;
+
+ b_getch(input); /* get the & */
+ while (ch=b_peek(input),isdigit(ch)) {
+ d = d*10+(ch-'0');
+ ok=1;
+ b_getch(input);
+ }
+ if (ok) return d;
+
+ fprintf(stderr, "ambiguous redirect\n");
+ return -2;
+}
+
+/* If a redirect is immediately preceded by a number, that number is
+ * supposed to tell which file descriptor to redirect. This routine
+ * looks for such preceding numbers. In an ideal world this routine
+ * needs to handle all the following classes of redirects...
+ * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
+ * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
+ * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
+ * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
+ * A -1 output from this program means no valid number was found, so the
+ * caller should use the appropriate default for this redirection.
+ */
+static int redirect_opt_num(o_string *o)
+{
+ int num;
+
+ if (o->length==0) return -1;
+ for(num=0; num<o->length; num++) {
+ if (!isdigit(*(o->data+num))) {
+ return -1;
+ }
+ }
+ /* reuse num (and save an int) */
+ num=atoi(o->data);
+ b_reset(o);
+ return num;
+}
+
+FILE *generate_stream_from_list(struct pipe *head)
+{
+ FILE *pf;
+#if 1
+ int pid, channel[2];
+ if (pipe(channel)<0) perror_msg_and_die("pipe");
+ pid=fork();
+ if (pid<0) {
+ perror_msg_and_die("fork");
+ } else if (pid==0) {
+ close(channel[0]);
+ if (channel[1] != 1) {
+ dup2(channel[1],1);
+ close(channel[1]);
+ }
+#if 0
+#define SURROGATE "surrogate response"
+ write(1,SURROGATE,sizeof(SURROGATE));
+ exit(run_list(head));
+#else
+ exit(run_list_real(head)); /* leaks memory */
+#endif
+ }
+ debug_printf("forked child %d\n",pid);
+ close(channel[1]);
+ pf = fdopen(channel[0],"r");
+ debug_printf("pipe on FILE *%p\n",pf);
+#else
+ run_list_test(head,0);
+ pf=popen("echo surrogate response","r");
+ debug_printf("started fake pipe on FILE *%p\n",pf);
+#endif
+ return pf;
+}
+
+/* this version hacked for testing purposes */
+/* return code is exit status of the process that is run. */
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
+{
+ int retcode;
+ o_string result=NULL_O_STRING;
+ struct p_context inner;
+ FILE *p;
+ struct in_str pipe_str;
+ initialize_context(&inner);
+
+ /* recursion to generate command */
+ retcode = parse_stream(&result, &inner, input, subst_end);
+ if (retcode != 0) return retcode; /* syntax error or EOF */
+ done_word(&result, &inner);
+ done_pipe(&inner, PIPE_SEQ);
+ b_free(&result);
+
+ p=generate_stream_from_list(inner.list_head);
+ if (p==NULL) return 1;
+ mark_open(fileno(p));
+ setup_file_in_str(&pipe_str, p);
+
+ /* now send results of command back into original context */
+ retcode = parse_stream(dest, ctx, &pipe_str, '\0');
+ /* XXX In case of a syntax error, should we try to kill the child?
+ * That would be tough to do right, so just read until EOF. */
+ if (retcode == 1) {
+ while (b_getch(&pipe_str)!=EOF) { /* discard */ };
+ }
+
+ debug_printf("done reading from pipe, pclose()ing\n");
+ /* This is the step that wait()s for the child. Should be pretty
+ * safe, since we just read an EOF from its stdout. We could try
+ * to better, by using wait(), and keeping track of background jobs
+ * at the same time. That would be a lot of work, and contrary
+ * to the KISS philosophy of this program. */
+ mark_closed(fileno(p));
+ retcode=pclose(p);
+ debug_printf("pclosed, retcode=%d\n",retcode);
+ /* XXX this process fails to trim a single trailing newline */
+ return retcode;
+}
+
+static int parse_group(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int ch)
+{
+ int rcode, endch=0;
+ struct p_context sub;
+ struct child_prog *child = ctx->child;
+ if (child->argv) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ initialize_context(&sub);
+ switch(ch) {
+ case '(': endch=')'; child->subshell=1; break;
+ case '{': endch='}'; break;
+ default: syntax(); /* really logic error */
+ }
+ rcode=parse_stream(dest,&sub,input,endch);
+ done_word(dest,&sub); /* finish off the final word in the subcontext */
+ done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
+ child->group = sub.list_head;
+ return rcode;
+ /* child remains "open", available for possible redirects */
+}
+
+/* basically useful version until someone wants to get fancier,
+ * see the bash man page under "Parameter Expansion" */
+static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src)
+{
+ const char *p=NULL;
+ if (src->data) p = getenv(src->data);
+ if (p) parse_string(dest, ctx, p); /* recursion */
+ b_free(src);
+}
+
+/* return code: 0 for OK, 1 for syntax error */
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
+{
+ int i, advance=0;
+ o_string alt=NULL_O_STRING;
+ char sep[]=" ";
+ int ch = input->peek(input); /* first character after the $ */
+ debug_printf("handle_dollar: ch=%c\n",ch);
+ if (isalpha(ch)) {
+ while(ch=b_peek(input),isalnum(ch) || ch=='_') {
+ b_getch(input);
+ b_addchr(&alt,ch);
+ }
+ lookup_param(dest, ctx, &alt);
+ } else if (isdigit(ch)) {
+ i = ch-'0'; /* XXX is $0 special? */
+ if (i<global_argc) {
+ parse_string(dest, ctx, global_argv[i]); /* recursion */
+ }
+ advance = 1;
+ } else switch (ch) {
+ case '$':
+ b_adduint(dest,getpid());
+ advance = 1;
+ break;
+ case '!':
+ if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
+ advance = 1;
+ break;
+ case '?':
+ b_adduint(dest,last_return_code);
+ advance = 1;
+ break;
+ case '#':
+ b_adduint(dest,global_argc ? global_argc-1 : 0);
+ advance = 1;
+ break;
+ case '{':
+ b_getch(input);
+ /* XXX maybe someone will try to escape the '}' */
+ while(ch=b_getch(input),ch!=EOF && ch!='}') {
+ b_addchr(&alt,ch);
+ }
+ if (ch != '}') {
+ syntax();
+ return 1;
+ }
+ lookup_param(dest, ctx, &alt);
+ break;
+ case '(':
+ process_command_subs(dest, ctx, input, ')');
+ break;
+ case '*':
+ sep[0]=ifs[0];
+ for (i=1; i<global_argc; i++) {
+ parse_string(dest, ctx, global_argv[i]);
+ if (i+1 < global_argc) parse_string(dest, ctx, sep);
+ }
+ break;
+ case '@':
+ case '-':
+ case '_':
+ /* still unhandled, but should be eventually */
+ fprintf(stderr,"unhandled syntax: $%c\n",ch);
+ return 1;
+ break;
+ default:
+ b_addqchr(dest,'$',dest->quote);
+ }
+ /* Eat the character if the flag was set. If the compiler
+ * is smart enough, we could substitute "b_getch(input);"
+ * for all the "advance = 1;" above, and also end up with
+ * a nice size-optimized program. Hah! That'll be the day.
+ */
+ if (advance) b_getch(input);
+ return 0;
+}
+
+int parse_string(o_string *dest, struct p_context *ctx, const char *src)
+{
+ struct in_str foo;
+ setup_string_in_str(&foo, src);
+ return parse_stream(dest, ctx, &foo, '\0');
+}
+
+/* return code is 0 for normal exit, 1 for syntax error */
+int parse_stream(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int end_trigger)
+{
+ unsigned int ch, m;
+ int redir_fd;
+ redir_type redir_style;
+ int next;
+
+ /* Only double-quote state is handled in the state variable dest->quote.
+ * A single-quote triggers a bypass of the main loop until its mate is
+ * found. When recursing, quote state is passed in via dest->quote. */
+
+ debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
+ while ((ch=b_getch(input))!=EOF) {
+ m = map[ch];
+ next = (ch == '\n') ? 0 : b_peek(input);
+ debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
+ ch,ch,m,dest->quote);
+ if (m==0 || ((m==1 || m==2) && dest->quote)) {
+ b_addqchr(dest, ch, dest->quote);
+ } else if (ch == end_trigger && !dest->quote) {
+ debug_printf("leaving parse_stream\n");
+ return 0;
+ } else if (m==2 && !dest->quote) { /* IFS */
+ done_word(dest, ctx);
+#if 0
+ if (ch=='\n') {
+ /* Yahoo! Time to run with it! */
+ done_pipe(ctx,PIPE_SEQ);
+ run_list(ctx->list_head);
+ initialize_context(ctx);
+ }
+#endif
+ } else switch (ch) {
+ case '#':
+ if (dest->length == 0 && !dest->quote) {
+ while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
+ } else {
+ b_addqchr(dest, ch, dest->quote);
+ }
+ break;
+ case '\\':
+ if (next == EOF) {
+ syntax();
+ return 1;
+ }
+ b_addqchr(dest, '\\', dest->quote);
+ b_addqchr(dest, b_getch(input), dest->quote);
+ break;
+ case '$':
+ if (handle_dollar(dest, ctx, input)!=0) return 1;
+ break;
+ case '\'':
+ dest->nonnull = 1;
+ while(ch=b_getch(input),ch!=EOF && ch!='\'') {
+ b_addchr(dest,ch);
+ }
+ if (ch==EOF) {
+ syntax();
+ return 1;
+ }
+ break;
+ case '"':
+ dest->nonnull = 1;
+ dest->quote = !dest->quote;
+ break;
+ case '`':
+ process_command_subs(dest, ctx, input, '`');
+ break;
+ case '>':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style=REDIRECT_OVERWRITE;
+ if (next == '>') {
+ redir_style=REDIRECT_APPEND;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support >(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case '<':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style=REDIRECT_INPUT;
+ if (next == '<') {
+ redir_style=REDIRECT_HEREIS;
+ b_getch(input);
+ } else if (next == '>') {
+ redir_style=REDIRECT_IO;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support <(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case ';':
+ done_word(dest, ctx);
+ done_pipe(ctx,PIPE_SEQ);
+ break;
+ case '&':
+ done_word(dest, ctx);
+ if (next=='&') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_AND);
+ } else {
+ done_pipe(ctx,PIPE_BG);
+ }
+ break;
+ case '|':
+ done_word(dest, ctx);
+ if (next=='|') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_OR);
+ } else {
+ /* we could pick up a file descriptor choice here
+ * with redirect_opt_num(), but bash doesn't do it.
+ * "echo foo 2| cat" yields "foo 2". */
+ done_command(ctx);
+ }
+ break;
+ case '(':
+ case '{':
+ if (parse_group(dest, ctx, input, ch)!=0) return 1;
+ break;
+ case ')':
+ case '}':
+ syntax(); /* Proper use of this character caught by end_trigger */
+ return 1;
+ break;
+ default:
+ syntax(); /* this is really an internal logic error */
+ return 1;
+ }
+ }
+ /* complain if quote? No, maybe we just finished a command substitution
+ * that was quoted. Example:
+ * $ echo "`cat foo` plus more"
+ * and we just got the EOF generated by the subshell that ran "cat foo"
+ * The only real complaint is if we got an EOF when end_trigger != '\0',
+ * that is, we were really supposed to get end_trigger, and never got
+ * one before the EOF. Can't use the standard "syntax error" return code,
+ * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
+ if (end_trigger != '\0') return -1;
+ return 0;
+}
+
+void mapset(const unsigned char *set, int code)
+{
+ const unsigned char *s;
+ for (s=set; *s; s++) map[*s] = code;
+}
+
+void update_ifs_map(void)
+{
+ /* char *ifs and char map[256] are both globals. */
+ ifs = getenv("IFS");
+ if (ifs == NULL) ifs=" \t\n";
+ /* Precompute a list of 'flow through' behavior so it can be treated
+ * quickly up front. Computation is necessary because of IFS.
+ * Special case handling of IFS == " \t\n" is not implemented.
+ * The map[] array only really needs two bits each, and on most machines
+ * that would be faster because of the reduced L1 cache footprint.
+ */
+ memset(map,0,256); /* most characters flow through always */
+ mapset("\\$'\"`", 3); /* never flow through */
+ mapset("<>;&|(){}#", 1); /* flow through if quoted */
+ mapset(ifs, 2); /* also flow through if quoted */
+}
+
+/* most recursion does not come through here, the exeception is
+ * from builtin_source() */
+int parse_stream_outer(struct in_str *inp)
+{
+
+ struct p_context ctx;
+ o_string temp=NULL_O_STRING;
+ int rcode;
+ do {
+ initialize_context(&ctx);
+ update_ifs_map();
+ inp->promptmode=1;
+ rcode = parse_stream(&temp, &ctx, inp, '\n');
+ done_word(&temp, &ctx);
+ done_pipe(&ctx,PIPE_SEQ);
+ run_list(ctx.list_head);
+ } while (rcode != -1); /* loop on syntax errors, return on EOF */
+ return 0;
+}
+
+static int parse_string_outer(const char *s)
+{
+ struct in_str input;
+ setup_string_in_str(&input, s);
+ return parse_stream_outer(&input);
+}
+
+static int parse_file_outer(FILE *f)
+{
+ int rcode;
+ struct in_str input;
+ setup_file_in_str(&input, f);
+ rcode = parse_stream_outer(&input);
+ return rcode;
+}
+
+int shell_main(int argc, char **argv)
+{
+ int opt;
+ FILE *input;
+
+ /* XXX what should these be while sourcing /etc/profile? */
+ global_argc = argc;
+ global_argv = argv;
+
+ if (argv[0] && argv[0][0] == '-') {
+ debug_printf("\nsourcing /etc/profile\n");
+ input = xfopen("/etc/profile", "r");
+ mark_open(fileno(input));
+ parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ }
+ input=stdin;
+
+ /* initialize the cwd -- this is never freed...*/
+ cwd = xgetcwd(0);
+#ifdef BB_FEATURE_COMMAND_EDITING
+ cmdedit_set_initial_prompt();
+#else
+ PS1 = NULL;
+#endif
+
+ while ((opt = getopt(argc, argv, "c:xif")) > 0) {
+ switch (opt) {
+ case 'c':
+ {
+ global_argv = argv+optind;
+ global_argc = argc-optind;
+ opt = parse_string_outer(optarg);
+ exit(opt);
+ }
+ break;
+ case 'i':
+ interactive++;
+ break;
+ case 'f':
+ fake_mode++;
+ break;
+ default:
+ fprintf(stderr, "Usage: sh [FILE]...\n"
+ " or: sh -c command [args]...\n\n");
+ exit(EXIT_FAILURE);
+ }
+ }
+ /* A shell is interactive if the `-i' flag was given, or if all of
+ * the following conditions are met:
+ * no -c command
+ * no arguments remaining or the -s flag given
+ * standard input is a terminal
+ * standard output is a terminal
+ * Refer to Posix.2, the description of the `sh' utility. */
+ if (argv[optind]==NULL && input==stdin &&
+ isatty(fileno(stdin)) && isatty(fileno(stdout))) {
+ interactive++;
+ }
+
+ if (interactive) {
+ /* Looks like they want an interactive shell */
+ fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ exit(parse_file_outer(stdin));
+ }
+ debug_printf("\ninteractive=%d\n", interactive);
+
+ debug_printf("\nrunning script '%s'\n", argv[optind]);
+ global_argv = argv+optind;
+ global_argc = argc-optind;
+ input = xfopen(argv[optind], "r");
+ opt = parse_file_outer(input);
+
+#ifdef BB_FEATURE_CLEAN_UP
+ fclose(input.file);
+#endif
+
+ return(opt);
+}
diff --git a/sh.c b/sh.c
deleted file mode 100644
index 1d12835..0000000
--- a/sh.c
+++ /dev/null
@@ -1,1935 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * lash -- the BusyBox Lame-Ass SHell
- *
- * Copyright (C) 1999,2000,2001 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
- *
- * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is
- * under the following liberal license: "We have placed this source code in the
- * public domain. Use it in any project, free or commercial."
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- */
-
-/* The parsing engine of this program is officially at a dead-end.
- * Future work in that direction should move to the work posted
- * at http://doolittle.faludi.com/~larry/parser.html .
- * A start on the integration of that work with the rest of sh.c
- * is at http://codepoet.org/sh.c .
- */
-//
-//This works pretty well now, and is now on by default.
-#define BB_FEATURE_SH_ENVIRONMENT
-//
-//Backtick support has some problems, use at your own risk!
-//#define BB_FEATURE_SH_BACKTICKS
-//
-//If, then, else, etc. support.. This should now behave basically
-//like any other Bourne shell -- sortof...
-#define BB_FEATURE_SH_IF_EXPRESSIONS
-//
-/* This is currently sortof broken, only for the brave... */
-#undef HANDLE_CONTINUATION_CHARS
-//
-/* This would be great -- if wordexp wouldn't strip all quoting
- * out from the target strings... As is, a parser needs */
-#undef BB_FEATURE_SH_WORDEXP
-//
-//For debugging/development on the shell only...
-//#define DEBUG_SHELL
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <sys/wait.h>
-#include <unistd.h>
-#include <getopt.h>
-#include "busybox.h"
-#include "cmdedit.h"
-
-#ifdef BB_LOCALE_SUPPORT
-#include <locale.h>
-#endif
-
-//#define BB_FEATURE_SH_WORDEXP
-
-#ifdef BB_FEATURE_SH_WORDEXP
-#include <wordexp.h>
-#define expand_t wordexp_t
-#undef BB_FEATURE_SH_BACKTICKS
-#else
-#include <glob.h>
-#define expand_t glob_t
-#endif
-
-
-static const int MAX_READ = 128; /* size of input buffer for `read' builtin */
-#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
-
-
-enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE,
- REDIRECT_APPEND
-};
-
-static const unsigned int DEFAULT_CONTEXT=0x1;
-static const unsigned int IF_TRUE_CONTEXT=0x2;
-static const unsigned int IF_FALSE_CONTEXT=0x4;
-static const unsigned int THEN_EXP_CONTEXT=0x8;
-static const unsigned int ELSE_EXP_CONTEXT=0x10;
-
-
-struct jobset {
- struct job *head; /* head of list of running jobs */
- struct job *fg; /* current foreground job */
-};
-
-struct redir_struct {
- enum redir_type type; /* type of redirection */
- int fd; /* file descriptor being redirected */
- char *filename; /* file to redirect fd to */
-};
-
-struct child_prog {
- pid_t pid; /* 0 if exited */
- char **argv; /* program name and arguments */
- int num_redirects; /* elements in redirection array */
- struct redir_struct *redirects; /* I/O redirects */
- int is_stopped; /* is the program currently running? */
- struct job *family; /* pointer back to the child's parent job */
-};
-
-struct job {
- int jobid; /* job number */
- int num_progs; /* total number of programs in job */
- int running_progs; /* number of programs running */
- char *text; /* name of job */
- char *cmdbuf; /* buffer various argv's point into */
- pid_t pgrp; /* process group ID for the job */
- struct child_prog *progs; /* array of programs in job */
- struct job *next; /* to track background commands */
- int stopped_progs; /* number of programs alive, but stopped */
- unsigned int job_context; /* bitmask defining current context */
- struct jobset *job_list;
-};
-
-struct built_in_command {
- char *cmd; /* name */
- char *descr; /* description */
- int (*function) (struct child_prog *); /* function ptr */
-};
-
-struct close_me {
- int fd;
- struct close_me *next;
-};
-
-/* function prototypes for builtins */
-static int builtin_cd(struct child_prog *cmd);
-static int builtin_exec(struct child_prog *cmd);
-static int builtin_exit(struct child_prog *cmd);
-static int builtin_fg_bg(struct child_prog *cmd);
-static int builtin_help(struct child_prog *cmd);
-static int builtin_jobs(struct child_prog *dummy);
-static int builtin_pwd(struct child_prog *dummy);
-static int builtin_export(struct child_prog *cmd);
-static int builtin_source(struct child_prog *cmd);
-static int builtin_unset(struct child_prog *cmd);
-static int builtin_read(struct child_prog *cmd);
-#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
-static int builtin_if(struct child_prog *cmd);
-static int builtin_then(struct child_prog *cmd);
-static int builtin_else(struct child_prog *cmd);
-static int builtin_fi(struct child_prog *cmd);
-/* function prototypes for shell stuff */
-static int run_command_predicate(char *cmd);
-#endif
-
-
-/* function prototypes for shell stuff */
-static void mark_open(int fd);
-static void mark_closed(int fd);
-static void close_all(void);
-static void checkjobs(struct jobset *job_list);
-static int get_command(FILE * source, char *command);
-static int parse_command(char **command_ptr, struct job *job, int *inbg);
-static int run_command(struct job *newjob, int inbg, int outpipe[2]);
-static int pseudo_exec(struct child_prog *cmd) __attribute__ ((noreturn));
-static int busy_loop(FILE * input);
-
-
-/* Table of built-in functions (these are non-forking builtins, meaning they
- * can change global variables in the parent shell process but they will not
- * work with pipes and redirects; 'unset foo | whatever' will not work) */
-static struct built_in_command bltins[] = {
- {"bg", "Resume a job in the background", builtin_fg_bg},
- {"cd", "Change working directory", builtin_cd},
- {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec},
- {"exit", "Exit from shell()", builtin_exit},
- {"fg", "Bring job into the foreground", builtin_fg_bg},
- {"jobs", "Lists the active jobs", builtin_jobs},
- {"export", "Set environment variable", builtin_export},
- {"unset", "Unset environment variable", builtin_unset},
- {"read", "Input environment variable", builtin_read},
- {".", "Source-in and run commands in a file", builtin_source},
- /* to do: add ulimit */
-#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
- {"if", NULL, builtin_if},
- {"then", NULL, builtin_then},
- {"else", NULL, builtin_else},
- {"fi", NULL, builtin_fi},
-#endif
- {NULL, NULL, NULL}
-};
-
-/* Table of forking built-in functions (things that fork cannot change global
- * variables in the parent process, such as the current working directory) */
-static struct built_in_command bltins_forking[] = {
- {"pwd", "Print current directory", builtin_pwd},
- {"help", "List shell built-in commands", builtin_help},
- {NULL, NULL, NULL}
-};
-
-
-/* Variables we export */
-unsigned int shell_context; /* Used in cmdedit.c to reset the
- context when someone hits ^C */
-
-
-/* Globals that are static to this file */
-static char *cwd;
-static char *local_pending_command = NULL;
-static struct jobset job_list = { NULL, NULL };
-static int argc;
-static char **argv;
-static struct close_me *close_me_head;
-#ifdef BB_FEATURE_SH_ENVIRONMENT
-static int last_bg_pid;
-static int last_return_code;
-static int show_x_trace;
-#endif
-#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
-static char syntax_err[]="syntax error near unexpected token";
-#endif
-
-static char *PS1;
-static char *PS2 = "> ";
-
-
-#ifdef DEBUG_SHELL
-static inline void debug_printf(const char *format, ...)
-{
- va_list args;
- va_start(args, format);
- vfprintf(stderr, format, args);
- va_end(args);
-}
-#else
-static inline void debug_printf(const char *format, ...) { }
-#endif
-
-/*
- Most builtins need access to the struct child_prog that has
- their arguments, previously coded as cmd->progs[0]. That coding
- can exhibit a bug, if the builtin is not the first command in
- a pipeline: "echo foo | exec sort" will attempt to exec foo.
-
-builtin previous use notes
------- ----------------- ---------
-cd cmd->progs[0]
-exec cmd->progs[0] squashed bug: didn't look for applets or forking builtins
-exit cmd->progs[0]
-fg_bg cmd->progs[0], job_list->head, job_list->fg
-help 0
-jobs job_list->head
-pwd 0
-export cmd->progs[0]
-source cmd->progs[0]
-unset cmd->progs[0]
-read cmd->progs[0]
-if cmd->job_context, cmd->text
-then cmd->job_context, cmd->text
-else cmd->job_context, cmd->text
-fi cmd->job_context
-
-The use of cmd->text by if/then/else/fi is hopelessly hacky.
-Would it work to increment cmd->progs[0]->argv and recurse,
-somewhat like builtin_exec does?
-
-I added "struct job *family;" to struct child_prog,
-and switched API to builtin_foo(struct child_prog *child);
-So cmd->text becomes child->family->text
- cmd->job_context becomes child->family->job_context
- cmd->progs[0] becomes *child
- job_list becomes child->family->job_list
- */
-
-/* built-in 'cd <path>' handler */
-static int builtin_cd(struct child_prog *child)
-{
- char *newdir;
-
- if (child->argv[1] == NULL)
- newdir = getenv("HOME");
- else
- newdir = child->argv[1];
- if (chdir(newdir)) {
- printf("cd: %s: %m\n", newdir);
- return EXIT_FAILURE;
- }
- cwd = xgetcwd(cwd);
-
- return EXIT_SUCCESS;
-}
-
-/* built-in 'exec' handler */
-static int builtin_exec(struct child_prog *child)
-{
- if (child->argv[1] == NULL)
- return EXIT_SUCCESS; /* Really? */
- child->argv++;
- close_all();
- pseudo_exec(child);
- /* never returns */
-}
-
-/* built-in 'exit' handler */
-static int builtin_exit(struct child_prog *child)
-{
- if (child->argv[1] == NULL)
- exit(EXIT_SUCCESS);
-
- exit (atoi(child->argv[1]));
-}
-
-/* built-in 'fg' and 'bg' handler */
-static int builtin_fg_bg(struct child_prog *child)
-{
- int i, jobNum;
- struct job *job=NULL;
-
- if (!child->argv[1] || child->argv[2]) {
- error_msg("%s: exactly one argument is expected",
- child->argv[0]);
- return EXIT_FAILURE;
- }
-
- if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
- error_msg("%s: bad argument '%s'",
- child->argv[0], child->argv[1]);
- return EXIT_FAILURE;
- }
-
- for (job = child->family->job_list->head; job; job = job->next) {
- if (job->jobid == jobNum) {
- break;
- }
- }
-
- if (!job) {
- error_msg("%s: unknown job %d",
- child->argv[0], jobNum);
- return EXIT_FAILURE;
- }
-
- if (*child->argv[0] == 'f') {
- /* Make this job the foreground job */
- /* suppress messages when run from /linuxrc mag@sysgo.de */
- if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
- child->family->job_list->fg = job;
- }
-
- /* Restart the processes in the job */
- for (i = 0; i < job->num_progs; i++)
- job->progs[i].is_stopped = 0;
-
- kill(-job->pgrp, SIGCONT);
-
- job->stopped_progs = 0;
-
- return EXIT_SUCCESS;
-}
-
-/* built-in 'help' handler */
-static int builtin_help(struct child_prog *dummy)
-{
- struct built_in_command *x;
-
- printf("\nBuilt-in commands:\n");
- printf("-------------------\n");
- for (x = bltins; x->cmd; x++) {
- if (x->descr==NULL)
- continue;
- printf("%s\t%s\n", x->cmd, x->descr);
- }
- for (x = bltins_forking; x->cmd; x++) {
- if (x->descr==NULL)
- continue;
- printf("%s\t%s\n", x->cmd, x->descr);
- }
- printf("\n\n");
- return EXIT_SUCCESS;
-}
-
-/* built-in 'jobs' handler */
-static int builtin_jobs(struct child_prog *child)
-{
- struct job *job;
- char *status_string;
-
- for (job = child->family->job_list->head; job; job = job->next) {
- if (job->running_progs == job->stopped_progs)
- status_string = "Stopped";
- else
- status_string = "Running";
-
- printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
- }
- return EXIT_SUCCESS;
-}
-
-
-/* built-in 'pwd' handler */
-static int builtin_pwd(struct child_prog *dummy)
-{
- printf( "%s\n", cwd);
- return EXIT_SUCCESS;
-}
-
-/* built-in 'export VAR=value' handler */
-static int builtin_export(struct child_prog *child)
-{
- int res;
- char *v = child->argv[1];
-
- if (v == NULL) {
- char **e;
- for (e = environ; *e; e++) {
- printf( "%s\n", *e);
- }
- return 0;
- }
- res = putenv(v);
- if (res)
- fprintf(stderr, "export: %m\n");
-#ifndef BB_FEATURE_SH_SIMPLE_PROMPT
- if (strncmp(v, "PS1=", 4)==0)
- PS1 = getenv("PS1");
-#endif
-
-#ifdef BB_LOCALE_SUPPORT
- if(strncmp(v, "LC_ALL=", 7)==0)
- setlocale(LC_ALL, getenv("LC_ALL"));
- if(strncmp(v, "LC_CTYPE=", 9)==0)
- setlocale(LC_CTYPE, getenv("LC_CTYPE"));
-#endif
-
- return (res);
-}
-
-/* built-in 'read VAR' handler */
-static int builtin_read(struct child_prog *child)
-{
- int res = 0, len, newlen;
- char *s;
- char string[MAX_READ];
-
- if (child->argv[1]) {
- /* argument (VAR) given: put "VAR=" into buffer */
- strcpy(string, child->argv[1]);
- len = strlen(string);
- string[len++] = '=';
- string[len] = '\0';
- fgets(&string[len], sizeof(string) - len, stdin); /* read string */
- newlen = strlen(string);
- if(newlen > len)
- string[--newlen] = '\0'; /* chomp trailing newline */
- /*
- ** string should now contain "VAR=<value>"
- ** copy it (putenv() won't do that, so we must make sure
- ** the string resides in a static buffer!)
- */
- res = -1;
- if((s = strdup(string)))
- res = putenv(s);
- if (res)
- fprintf(stderr, "read: %m\n");
- }
- else
- fgets(string, sizeof(string), stdin);
-
- return (res);
-}
-
-#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
-/* Built-in handler for 'if' commands */
-static int builtin_if(struct child_prog *child)
-{
- struct job *cmd = child->family;
- int status;
- char* charptr1=cmd->text+3; /* skip over the leading 'if ' */
-
- /* Now run the 'if' command */
- debug_printf( "job=%p entering builtin_if ('%s')-- context=%d\n", cmd, charptr1, cmd->job_context);
- status = run_command_predicate(charptr1);
- debug_printf( "if test returned ");
- if (status == 0) {
- debug_printf( "TRUE\n");
- cmd->job_context |= IF_TRUE_CONTEXT;
- } else {
- debug_printf( "FALSE\n");
- cmd->job_context |= IF_FALSE_CONTEXT;
- }
- debug_printf("job=%p builtin_if set job context to %x\n", cmd, cmd->job_context);
- shell_context++;
-
- return status;
-}
-
-/* Built-in handler for 'then' (part of the 'if' command) */
-static int builtin_then(struct child_prog *child)
-{
- struct job *cmd = child->family;
- char* charptr1=cmd->text+5; /* skip over the leading 'then ' */
-
- debug_printf( "job=%p entering builtin_then ('%s')-- context=%d\n", cmd, charptr1, cmd->job_context);
- if (! (cmd->job_context & (IF_TRUE_CONTEXT|IF_FALSE_CONTEXT))) {
- shell_context = 0; /* Reset the shell's context on an error */
- error_msg("%s `then'", syntax_err);
- return EXIT_FAILURE;
- }
-
- cmd->job_context |= THEN_EXP_CONTEXT;
- debug_printf("job=%p builtin_then set job context to %x\n", cmd, cmd->job_context);
-
- /* If the if result was FALSE, skip the 'then' stuff */
- if (cmd->job_context & IF_FALSE_CONTEXT) {
- return EXIT_SUCCESS;
- }
-
- /* Seems the if result was TRUE, so run the 'then' command */
- debug_printf( "'then' now running '%s'\n", charptr1);
-
- return(run_command_predicate(charptr1));
-}
-
-/* Built-in handler for 'else' (part of the 'if' command) */
-static int builtin_else(struct child_prog *child)
-{
- struct job *cmd = child->family;
- char* charptr1=cmd->text+5; /* skip over the leading 'else ' */
-
- debug_printf( "job=%p entering builtin_else ('%s')-- context=%d\n", cmd, charptr1, cmd->job_context);
-
- if (! (cmd->job_context & THEN_EXP_CONTEXT)) {
- shell_context = 0; /* Reset the shell's context on an error */
- error_msg("%s `else'", syntax_err);
- return EXIT_FAILURE;
- }
- /* If the if result was TRUE, skip the 'else' stuff */
- if (cmd->job_context & IF_TRUE_CONTEXT) {
- return EXIT_SUCCESS;
- }
-
- cmd->job_context |= ELSE_EXP_CONTEXT;
- debug_printf("job=%p builtin_else set job context to %x\n", cmd, cmd->job_context);
-
- /* Now run the 'else' command */
- debug_printf( "'else' now running '%s'\n", charptr1);
- return(run_command_predicate(charptr1));
-}
-
-/* Built-in handler for 'fi' (part of the 'if' command) */
-static int builtin_fi(struct child_prog *child)
-{
- struct job *cmd = child->family;
- debug_printf( "job=%p entering builtin_fi ('%s')-- context=%d\n", cmd, "", cmd->job_context);
- if (! (cmd->job_context & (IF_TRUE_CONTEXT|IF_FALSE_CONTEXT))) {
- shell_context = 0; /* Reset the shell's context on an error */
- error_msg("%s `fi'", syntax_err);
- return EXIT_FAILURE;
- }
- /* Clear out the if and then context bits */
- cmd->job_context &= ~(IF_TRUE_CONTEXT|IF_FALSE_CONTEXT|THEN_EXP_CONTEXT|ELSE_EXP_CONTEXT);
- debug_printf("job=%p builtin_fi set job context to %x\n", cmd, cmd->job_context);
- shell_context--;
- return EXIT_SUCCESS;
-}
-#endif
-
-/* Built-in '.' handler (read-in and execute commands from file) */
-static int builtin_source(struct child_prog *child)
-{
- FILE *input;
- int status;
- int fd;
-
- if (child->argv[1] == NULL)
- return EXIT_FAILURE;
-
- input = fopen(child->argv[1], "r");
- if (!input) {
- printf( "Couldn't open file '%s'\n", child->argv[1]);
- return EXIT_FAILURE;
- }
-
- fd=fileno(input);
- mark_open(fd);
- /* Now run the file */
- status = busy_loop(input);
- fclose(input);
- mark_closed(fd);
- return (status);
-}
-
-/* built-in 'unset VAR' handler */
-static int builtin_unset(struct child_prog *child)
-{
- if (child->argv[1] == NULL) {
- printf( "unset: parameter required.\n");
- return EXIT_FAILURE;
- }
- unsetenv(child->argv[1]);
- return EXIT_SUCCESS;
-}
-
-#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
-/* currently used by if/then/else.
- *
- * Reparsing the command line for this purpose is gross,
- * incorrect, and fundamentally unfixable; in particular,
- * think about what happens with command substitution.
- * We really need to pull out the run, wait, return status
- * functionality out of busy_loop so we can child->argv++
- * and use that, without going back through parse_command.
- */
-static int run_command_predicate(char *cmd)
-{
- local_pending_command = xstrdup(cmd);
- return( busy_loop(NULL));
-}
-#endif
-
-static void mark_open(int fd)
-{
- struct close_me *new = xmalloc(sizeof(struct close_me));
- new->fd = fd;
- new->next = close_me_head;
- close_me_head = new;
-}
-
-static void mark_closed(int fd)
-{
- struct close_me *tmp;
- if (close_me_head == NULL || close_me_head->fd != fd)
- error_msg_and_die("corrupt close_me");
- tmp = close_me_head;
- close_me_head = close_me_head->next;
- free(tmp);
-}
-
-static void close_all()
-{
- struct close_me *c, *tmp;
- for (c=close_me_head; c; c=tmp) {
- close(c->fd);
- tmp=c->next;
- free(c);
- }
- close_me_head = NULL;
-}
-
-
-/* free up all memory from a job */
-static void free_job(struct job *cmd)
-{
- int i;
- struct jobset *keep;
-
- for (i = 0; i < cmd->num_progs; i++) {
- free(cmd->progs[i].argv);
- if (cmd->progs[i].redirects)
- free(cmd->progs[i].redirects);
- }
- if (cmd->progs)
- free(cmd->progs);
- if (cmd->text)
- free(cmd->text);
- if (cmd->cmdbuf)
- free(cmd->cmdbuf);
- keep = cmd->job_list;
- memset(cmd, 0, sizeof(struct job));
- cmd->job_list = keep;
-}
-
-/* remove a job from a jobset */
-static void remove_job(struct jobset *j_list, struct job *job)
-{
- struct job *prevjob;
-
- free_job(job);
- if (job == j_list->head) {
- j_list->head = job->next;
- } else {
- prevjob = j_list->head;
- while (prevjob->next != job)
- prevjob = prevjob->next;
- prevjob->next = job->next;
- }
-
- free(job);
-}
-
-/* Checks to see if any background processes have exited -- if they
- have, figure out why and see if a job has completed */
-static void checkjobs(struct jobset *j_list)
-{
- struct job *job;
- pid_t childpid;
- int status;
- int prognum = 0;
-
- while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
- for (job = j_list->head; job; job = job->next) {
- prognum = 0;
- while (prognum < job->num_progs &&
- job->progs[prognum].pid != childpid) prognum++;
- if (prognum < job->num_progs)
- break;
- }
-
- /* This happens on backticked commands */
- if(job==NULL)
- return;
-
- if (WIFEXITED(status) || WIFSIGNALED(status)) {
- /* child exited */
- job->running_progs--;
- job->progs[prognum].pid = 0;
-
- if (!job->running_progs) {
- printf(JOB_STATUS_FORMAT, job->jobid, "Done", job->text);
- remove_job(j_list, job);
- }
- } else {
- /* child stopped */
- job->stopped_progs++;
- job->progs[prognum].is_stopped = 1;
-
- if (job->stopped_progs == job->num_progs) {
- printf(JOB_STATUS_FORMAT, job->jobid, "Stopped",
- job->text);
- }
- }
- }
-
- if (childpid == -1 && errno != ECHILD)
- perror_msg("waitpid");
-}
-
-/* squirrel != NULL means we squirrel away copies of stdin, stdout,
- * and stderr if they are redirected. */
-static int setup_redirects(struct child_prog *prog, int squirrel[])
-{
- int i;
- int openfd;
- int mode = O_RDONLY;
- struct redir_struct *redir = prog->redirects;
-
- for (i = 0; i < prog->num_redirects; i++, redir++) {
- switch (redir->type) {
- case REDIRECT_INPUT:
- mode = O_RDONLY;
- break;
- case REDIRECT_OVERWRITE:
- mode = O_WRONLY | O_CREAT | O_TRUNC;
- break;
- case REDIRECT_APPEND:
- mode = O_WRONLY | O_CREAT | O_APPEND;
- break;
- }
-
- openfd = open(redir->filename, mode, 0666);
- if (openfd < 0) {
- /* this could get lost if stderr has been redirected, but
- bash and ash both lose it as well (though zsh doesn't!) */
- perror_msg("error opening %s", redir->filename);
- return 1;
- }
-
- if (openfd != redir->fd) {
- if (squirrel && redir->fd < 3) {
- squirrel[redir->fd] = dup(redir->fd);
- }
- dup2(openfd, redir->fd);
- close(openfd);
- }
- }
-
- return 0;
-}
-
-static void restore_redirects(int squirrel[])
-{
- int i, fd;
- for (i=0; i<3; i++) {
- fd = squirrel[i];
- if (fd != -1) {
- /* No error checking. I sure wouldn't know what
- * to do with an error if I found one! */
- dup2(fd, i);
- close(fd);
- }
- }
-}
-
-static inline void cmdedit_set_initial_prompt(void)
-{
-#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
- PS1 = NULL;
-#else
- PS1 = getenv("PS1");
- if(PS1==0)
- PS1 = "\\w \\$ ";
-#endif
-}
-
-static inline void setup_prompt_string(char **prompt_str)
-{
-#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
- /* Set up the prompt */
- if (shell_context == 0) {
- if (PS1)
- free(PS1);
- PS1=xmalloc(strlen(cwd)+4);
- sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
- *prompt_str = PS1;
- } else {
- *prompt_str = PS2;
- }
-#else
- *prompt_str = (shell_context==0)? PS1 : PS2;
-#endif
-}
-
-static int get_command(FILE * source, char *command)
-{
- char *prompt_str;
-
- if (source == NULL) {
- if (local_pending_command) {
- /* a command specified (-c option): return it & mark it done */
- strcpy(command, local_pending_command);
- free(local_pending_command);
- local_pending_command = NULL;
- return 0;
- }
- return 1;
- }
-
- if (source == stdin) {
- setup_prompt_string(&prompt_str);
-
-#ifdef BB_FEATURE_COMMAND_EDITING
- /*
- ** enable command line editing only while a command line
- ** is actually being read; otherwise, we'll end up bequeathing
- ** atexit() handlers and other unwanted stuff to our
- ** child processes (rob@sysgo.de)
- */
- cmdedit_read_input(prompt_str, command);
- cmdedit_terminate();
- return 0;
-#else
- fputs(prompt_str, stdout);
-#endif
- }
-
- if (!fgets(command, BUFSIZ - 2, source)) {
- if (source == stdin)
- printf("\n");
- return 1;
- }
-
- return 0;
-}
-
-#ifdef BB_FEATURE_SH_ENVIRONMENT
-static char* itoa(register int i)
-{
- static char a[7]; /* Max 7 ints */
- register char *b = a + sizeof(a) - 1;
- int sign = (i < 0);
-
- if (sign)
- i = -i;
- *b = 0;
- do
- {
- *--b = '0' + (i % 10);
- i /= 10;
- }
- while (i);
- if (sign)
- *--b = '-';
- return b;
-}
-#endif
-
-#if defined BB_FEATURE_SH_ENVIRONMENT && ! defined BB_FEATURE_SH_WORDEXP
-char * strsep_space( char *string, int * ix)
-{
- char *token, *begin;
-
- begin = string;
-
- /* Short circuit the trivial case */
- if ( !string || ! string[*ix])
- return NULL;
-
- /* Find the end of the token. */
- while( string && string[*ix] && !isspace(string[*ix]) ) {
- (*ix)++;
- }
-
- /* Find the end of any whitespace trailing behind
- * the token and let that be part of the token */
- while( string && string[*ix] && isspace(string[*ix]) ) {
- (*ix)++;
- }
-
- if (! string && *ix==0) {
- /* Nothing useful was found */
- return NULL;
- }
-
- token = xmalloc(*ix+1);
- token[*ix] = '\0';
- strncpy(token, string, *ix);
-
- return token;
-}
-#endif
-
-
-static int expand_arguments(char *command)
-{
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- expand_t expand_result;
- char *src, *dst, *var;
- int ix = 0;
- int i=0, length, total_length=0, retval;
- const char *out_of_space = "out of space during expansion";
-#endif
-
- /* get rid of the terminating \n */
- chomp(command);
-
- /* Fix up escape sequences to be the Real Thing(tm) */
- while( command && command[ix]) {
- if (command[ix] == '\\') {
- const char *tmp = command+ix+1;
- command[ix] = process_escape_sequence( &tmp );
- memmove(command+ix + 1, tmp, strlen(tmp)+1);
- }
- ix++;
- }
-
-#ifdef BB_FEATURE_SH_ENVIRONMENT
-
-
-#ifdef BB_FEATURE_SH_WORDEXP
- /* This first part uses wordexp() which is a wonderful C lib
- * function which expands nearly everything. */
- retval = wordexp (command, &expand_result, WRDE_SHOWERR);
- if (retval == WRDE_NOSPACE) {
- /* Mem may have been allocated... */
- wordfree (&expand_result);
- error_msg(out_of_space);
- return FALSE;
- }
- if (retval < 0) {
- /* Some other error. */
- error_msg("syntax error");
- return FALSE;
- }
-
- if (expand_result.we_wordc > 0) {
- /* Convert from char** (one word per string) to a simple char*,
- * but don't overflow command which is BUFSIZ in length */
- *command = '\0';
- while (i < expand_result.we_wordc && total_length < BUFSIZ) {
- length=strlen(expand_result.we_wordv[i])+1;
- if (BUFSIZ-total_length-length <= 0) {
- error_msg(out_of_space);
- return FALSE;
- }
- strcat(command+total_length, expand_result.we_wordv[i++]);
- strcat(command+total_length, " ");
- total_length+=length;
- }
- wordfree (&expand_result);
- }
-#else
-
- /* Ok. They don't have a recent glibc and they don't have uClibc. Chances
- * are about 100% they don't have wordexp(). So instead the best we can do
- * is use glob and then fixup environment variables and such ourselves.
- * This is better then nothing, but certainly not perfect */
-
- /* It turns out that glob is very stupid. We have to feed it one word at a
- * time since it can't cope with a full string. Here we convert command
- * (char*) into cmd (char**, one word per string) */
- {
-
- int flags = GLOB_NOCHECK
-#ifdef GLOB_BRACE
- | GLOB_BRACE
-#endif
-#ifdef GLOB_TILDE
- | GLOB_TILDE
-#endif
- ;
- char *tmpcmd, *cmd, *cmd_copy;
- /* We need a clean copy, so strsep can mess up the copy while
- * we write stuff into the original (in a minute) */
- cmd = cmd_copy = strdup(command);
- *command = '\0';
- for (ix = 0, tmpcmd = cmd;
- (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix=0) {
- if (*tmpcmd == '\0')
- break;
- /* we need to trim() the result for glob! */
- trim(tmpcmd);
- retval = glob(tmpcmd, flags, NULL, &expand_result);
- free(tmpcmd); /* Free mem allocated by strsep_space */
- if (retval == GLOB_NOSPACE) {
- /* Mem may have been allocated... */
- globfree (&expand_result);
- error_msg(out_of_space);
- return FALSE;
- } else if (retval != 0) {
- /* Some other error. GLOB_NOMATCH shouldn't
- * happen because of the GLOB_NOCHECK flag in
- * the glob call. */
- error_msg("syntax error");
- return FALSE;
- } else {
- /* Convert from char** (one word per string) to a simple char*,
- * but don't overflow command which is BUFSIZ in length */
- for (i=0; i < expand_result.gl_pathc; i++) {
- length=strlen(expand_result.gl_pathv[i]);
- if (total_length+length+1 >= BUFSIZ) {
- error_msg(out_of_space);
- return FALSE;
- }
- strcat(command+total_length, " ");
- total_length+=1;
- strcat(command+total_length, expand_result.gl_pathv[i]);
- total_length+=length;
- }
- globfree (&expand_result);
- }
- }
- free(cmd_copy);
- trim(command);
- }
-
-#endif
-
- /* Now do the shell variable substitutions which
- * wordexp can't do for us, namely $? and $! */
- src = command;
- while((dst = strchr(src,'$')) != NULL){
- var = NULL;
- switch(*(dst+1)) {
- case '?':
- var = itoa(last_return_code);
- break;
- case '!':
- if (last_bg_pid==-1)
- *(var)='\0';
- else
- var = itoa(last_bg_pid);
- break;
- /* Everything else like $$, $#, $[0-9], etc should all be
- * expanded by wordexp(), so we can in theory skip that stuff
- * here, but just to be on the safe side (i.e. since uClibc
- * wordexp doesn't do this stuff yet), lets leave it in for
- * now. */
- case '$':
- var = itoa(getpid());
- break;
- case '#':
- var = itoa(argc-1);
- break;
- case '0':case '1':case '2':case '3':case '4':
- case '5':case '6':case '7':case '8':case '9':
- {
- int ixx=*(dst + 1)-48;
- if (ixx >= argc) {
- var='\0';
- } else {
- var = argv[ixx];
- }
- }
- break;
-
- }
- if (var) {
- /* a single character construction was found, and
- * already handled in the case statement */
- src=dst+2;
- } else {
- /* Looks like an environment variable */
- char delim_hold;
- int num_skip_chars=0;
- int dstlen = strlen(dst);
- /* Is this a ${foo} type variable? */
- if (dstlen >=2 && *(dst+1) == '{') {
- src=strchr(dst+1, '}');
- num_skip_chars=1;
- } else {
- src=dst+1;
- while(isalnum(*src) || *src=='_') src++;
- }
- if (src == NULL) {
- src = dst+dstlen;
- }
- delim_hold=*src;
- *src='\0'; /* temporary */
- var = getenv(dst + 1 + num_skip_chars);
- *src=delim_hold;
- src += num_skip_chars;
- }
- if (var == NULL) {
- /* Seems we got an un-expandable variable. So delete it. */
- var = "";
- }
- {
- int subst_len = strlen(var);
- int trail_len = strlen(src);
- if (dst+subst_len+trail_len >= command+BUFSIZ) {
- error_msg(out_of_space);
- return FALSE;
- }
- /* Move stuff to the end of the string to accommodate
- * filling the created gap with the new stuff */
- memmove(dst+subst_len, src, trail_len+1);
- /* Now copy in the new stuff */
- memcpy(dst, var, subst_len);
- src = dst+subst_len;
- }
- }
-
-#endif
- return TRUE;
-}
-
-/* Return cmd->num_progs as 0 if no command is present (e.g. an empty
- line). If a valid command is found, command_ptr is set to point to
- the beginning of the next command (if the original command had more
- then one job associated with it) or NULL if no more commands are
- present. */
-static int parse_command(char **command_ptr, struct job *job, int *inbg)
-{
- char *command;
- char *return_command = NULL;
- char *src, *buf, *chptr;
- int argc_l = 0;
- int done = 0;
- int argv_alloced;
- int i, saw_quote = 0;
- char quote = '\0';
- int count;
- struct child_prog *prog;
-
- /* skip leading white space */
- while (**command_ptr && isspace(**command_ptr))
- (*command_ptr)++;
-
- /* this handles empty lines or leading '#' characters */
- if (!**command_ptr || (**command_ptr == '#')) {
- job->num_progs=0;
- return 0;
- }
-
- *inbg = 0;
- job->num_progs = 1;
- job->progs = xmalloc(sizeof(*job->progs));
-
- /* We set the argv elements to point inside of this string. The
- memory is freed by free_job(). Allocate twice the original
- length in case we need to quote every single character.
-
- Getting clean memory relieves us of the task of NULL
- terminating things and makes the rest of this look a bit
- cleaner (though it is, admittedly, a tad less efficient) */
- job->cmdbuf = command = xcalloc(2*strlen(*command_ptr) + 1, sizeof(char));
- job->text = NULL;
-
- prog = job->progs;
- prog->num_redirects = 0;
- prog->redirects = NULL;
- prog->is_stopped = 0;
- prog->family = job;
-
- argv_alloced = 5;
- prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
- prog->argv[0] = job->cmdbuf;
-
- buf = command;
- src = *command_ptr;
- while (*src && !done) {
- if (quote == *src) {
- quote = '\0';
- } else if (quote) {
- if (*src == '\\') {
- src++;
- if (!*src) {
- error_msg("character expected after \\");
- free_job(job);
- return 1;
- }
-
- /* in shell, "\'" should yield \' */
- if (*src != quote) {
- *buf++ = '\\';
- *buf++ = '\\';
- }
- } else if (*src == '*' || *src == '?' || *src == '[' ||
- *src == ']') *buf++ = '\\';
- *buf++ = *src;
- } else if (isspace(*src)) {
- if (*prog->argv[argc_l] || saw_quote) {
- buf++, argc_l++;
- /* +1 here leaves room for the NULL which ends argv */
- if ((argc_l + 1) == argv_alloced) {
- argv_alloced += 5;
- prog->argv = xrealloc(prog->argv,
- sizeof(*prog->argv) *
- argv_alloced);
- }
- prog->argv[argc_l] = buf;
- saw_quote = 0;
- }
- } else
- switch (*src) {
- case '"':
- case '\'':
- quote = *src;
- saw_quote = 1;
- break;
-
- case '#': /* comment */
- if (*(src-1)== '$')
- *buf++ = *src;
- else
- done = 1;
- break;
-
- case '>': /* redirects */
- case '<':
- i = prog->num_redirects++;
- prog->redirects = xrealloc(prog->redirects,
- sizeof(*prog->redirects) *
- (i + 1));
-
- prog->redirects[i].fd = -1;
- if (buf != prog->argv[argc_l]) {
- /* the stuff before this character may be the file number
- being redirected */
- prog->redirects[i].fd =
- strtol(prog->argv[argc_l], &chptr, 10);
-
- if (*chptr && *prog->argv[argc_l]) {
- buf++, argc_l++;
- prog->argv[argc_l] = buf;
- }
- }
-
- if (prog->redirects[i].fd == -1) {
- if (*src == '>')
- prog->redirects[i].fd = 1;
- else
- prog->redirects[i].fd = 0;
- }
-
- if (*src++ == '>') {
- if (*src == '>')
- prog->redirects[i].type =
- REDIRECT_APPEND, src++;
- else
- prog->redirects[i].type = REDIRECT_OVERWRITE;
- } else {
- prog->redirects[i].type = REDIRECT_INPUT;
- }
-
- /* This isn't POSIX sh compliant. Oh well. */
- chptr = src;
- while (isspace(*chptr))
- chptr++;
-
- if (!*chptr) {
- error_msg("file name expected after %c", *(src-1));
- free_job(job);
- job->num_progs=0;
- return 1;
- }
-
- prog->redirects[i].filename = buf;
- while (*chptr && !isspace(*chptr))
- *buf++ = *chptr++;
-
- src = chptr - 1; /* we src++ later */
- prog->argv[argc_l] = ++buf;
- break;
-
- case '|': /* pipe */
- /* finish this command */
- if (*prog->argv[argc_l] || saw_quote)
- argc_l++;
- if (!argc_l) {
- error_msg("empty command in pipe");
- free_job(job);
- job->num_progs=0;
- return 1;
- }
- prog->argv[argc_l] = NULL;
-
- /* and start the next */
- job->num_progs++;
- job->progs = xrealloc(job->progs,
- sizeof(*job->progs) * job->num_progs);
- prog = job->progs + (job->num_progs - 1);
- prog->num_redirects = 0;
- prog->redirects = NULL;
- prog->is_stopped = 0;
- prog->family = job;
- argc_l = 0;
-
- argv_alloced = 5;
- prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
- prog->argv[0] = ++buf;
-
- src++;
- while (*src && isspace(*src))
- src++;
-
- if (!*src) {
- error_msg("empty command in pipe");
- free_job(job);
- job->num_progs=0;
- return 1;
- }
- src--; /* we'll ++ it at the end of the loop */
-
- break;
-
- case '&': /* background */
- *inbg = 1;
- case ';': /* multiple commands */
- done = 1;
- return_command = *command_ptr + (src - *command_ptr) + 1;
- break;
-
-#ifdef BB_FEATURE_SH_BACKTICKS
- case '`':
- /* Exec a backtick-ed command */
- /* Besides any previous brokenness, I have not
- * updated backtick handling for close_me support.
- * I don't know if it needs it or not. -- LRD */
- {
- char* charptr1=NULL, *charptr2;
- char* ptr=NULL;
- struct job *newjob;
- struct jobset njob_list = { NULL, NULL };
- int pipefd[2];
- int size;
-
- ptr=strchr(++src, '`');
- if (ptr==NULL) {
- fprintf(stderr, "Unmatched '`' in command\n");
- free_job(job);
- return 1;
- }
-
- /* Make some space to hold just the backticked command */
- charptr1 = charptr2 = xmalloc(1+ptr-src);
- memcpy(charptr1, src, ptr-src);
- charptr1[ptr-src] = '\0';
- newjob = xmalloc(sizeof(struct job));
- newjob->job_list = &njob_list;
- /* Now parse and run the backticked command */
- if (!parse_command(&charptr1, newjob, inbg)
- && newjob->num_progs) {
- pipe(pipefd);
- run_command(newjob, 0, pipefd);
- }
- checkjobs(job->job_list);
- free_job(newjob); /* doesn't actually free newjob,
- looks like a memory leak */
- free(charptr2);
-
- /* Make a copy of any stuff left over in the command
- * line after the second backtick */
- charptr2 = xmalloc(strlen(ptr)+1);
- memcpy(charptr2, ptr+1, strlen(ptr));
-
-
- /* Copy the output from the backtick-ed command into the
- * command line, making extra room as needed */
- --src;
- charptr1 = xmalloc(BUFSIZ);
- while ( (size=full_read(pipefd[0], charptr1, BUFSIZ-1)) >0) {
- int newsize=src - *command_ptr + size + 1 + strlen(charptr2);
- if (newsize > BUFSIZ) {
- *command_ptr=xrealloc(*command_ptr, newsize);
- }
- memcpy(src, charptr1, size);
- src+=size;
- }
- free(charptr1);
- close(pipefd[0]);
- if (*(src-1)=='\n')
- --src;
-
- /* Now paste into the *command_ptr all the stuff
- * leftover after the second backtick */
- memcpy(src, charptr2, strlen(charptr2)+1);
- free(charptr2);
-
- /* Now recursively call parse_command to deal with the new
- * and improved version of the command line with the backtick
- * results expanded in place... */
- {
- struct jobset *jl=job->job_list;
- free_job(job);
- job->job_list = jl;
- }
- return(parse_command(command_ptr, job, inbg));
- }
- break;
-#endif // BB_FEATURE_SH_BACKTICKS
-
- case '\\':
- src++;
- if (!*src) {
-/* This is currently a little broken... */
-#ifdef HANDLE_CONTINUATION_CHARS
- /* They fed us a continuation char, so continue reading stuff
- * on the next line, then tack that onto the end of the current
- * command */
- char *command;
- int newsize;
- printf("erik: found a continue char at EOL...\n");
- command = (char *) xcalloc(BUFSIZ, sizeof(char));
- if (get_command(input, command)) {
- error_msg("character expected after \\");
- free(command);
- free_job(job);
- return 1;
- }
- newsize = strlen(*command_ptr) + strlen(command) + 2;
- if (newsize > BUFSIZ) {
- printf("erik: doing realloc\n");
- *command_ptr=xrealloc(*command_ptr, newsize);
- }
- printf("erik: A: *command_ptr='%s'\n", *command_ptr);
- memcpy(--src, command, strlen(command));
- printf("erik: B: *command_ptr='%s'\n", *command_ptr);
- free(command);
- break;
-#else
- error_msg("character expected after \\");
- free_job(job);
- return 1;
-#endif
- }
- if (*src == '*' || *src == '[' || *src == ']'
- || *src == '?') *buf++ = '\\';
- /* fallthrough */
- default:
- *buf++ = *src;
- }
-
- src++;
- }
-
- if (*prog->argv[argc_l] || saw_quote) {
- argc_l++;
- }
- if (!argc_l) {
- free_job(job);
- return 0;
- }
- prog->argv[argc_l] = NULL;
-
- if (!return_command) {
- job->text = xmalloc(strlen(*command_ptr) + 1);
- strcpy(job->text, *command_ptr);
- } else {
- /* This leaves any trailing spaces, which is a bit sloppy */
- count = return_command - *command_ptr;
- job->text = xmalloc(count + 1);
- strncpy(job->text, *command_ptr, count);
- job->text[count] = '\0';
- }
-
- *command_ptr = return_command;
-
- return 0;
-}
-
-/* Run the child_prog, no matter what kind of command it uses.
- */
-static int pseudo_exec(struct child_prog *child)
-{
- struct built_in_command *x;
-#ifdef BB_FEATURE_SH_STANDALONE_SHELL
- char *name;
-#endif
-
- /* Check if the command matches any of the non-forking builtins.
- * Depending on context, this might be redundant. But it's
- * easier to waste a few CPU cycles than it is to figure out
- * if this is one of those cases.
- */
- for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
- exit(x->function(child));
- }
- }
-
- /* Check if the command matches any of the forking builtins. */
- for (x = bltins_forking; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0) {
- applet_name=x->cmd;
- exit (x->function(child));
- }
- }
-#ifdef BB_FEATURE_SH_STANDALONE_SHELL
- /* Check if the command matches any busybox internal
- * commands ("applets") here. Following discussions from
- * November 2000 on busybox@opensource.lineo.com, don't use
- * get_last_path_component(). This way explicit (with
- * slashes) filenames will never be interpreted as an
- * applet, just like with builtins. This way the user can
- * override an applet with an explicit filename reference.
- * The only downside to this change is that an explicit
- * /bin/foo invocation will fork and exec /bin/foo, even if
- * /bin/foo is a symlink to busybox.
- */
- name = child->argv[0];
-
-#ifdef BB_FEATURE_SH_APPLETS_ALWAYS_WIN
- /* If you enable BB_FEATURE_SH_APPLETS_ALWAYS_WIN, then
- * if you run /bin/cat, it will use BusyBox cat even if
- * /bin/cat exists on the filesystem and is _not_ busybox.
- * Some systems want this, others do not. Choose wisely. :-)
- */
- name = get_last_path_component(name);
-#endif
-
- {
- char** argv_l=child->argv;
- int argc_l;
- for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++);
- optind = 1;
- run_applet_by_name(name, argc_l, child->argv);
- }
-#endif
-
- execvp(child->argv[0], child->argv);
- perror_msg_and_die("%s", child->argv[0]);
-}
-
-static void insert_job(struct job *newjob, int inbg)
-{
- struct job *thejob;
- struct jobset *j_list=newjob->job_list;
-
- /* find the ID for thejob to use */
- newjob->jobid = 1;
- for (thejob = j_list->head; thejob; thejob = thejob->next)
- if (thejob->jobid >= newjob->jobid)
- newjob->jobid = thejob->jobid + 1;
-
- /* add thejob to the list of running jobs */
- if (!j_list->head) {
- thejob = j_list->head = xmalloc(sizeof(*thejob));
- } else {
- for (thejob = j_list->head; thejob->next; thejob = thejob->next) /* nothing */;
- thejob->next = xmalloc(sizeof(*thejob));
- thejob = thejob->next;
- }
-
- *thejob = *newjob; /* physically copy the struct job */
- thejob->next = NULL;
- thejob->running_progs = thejob->num_progs;
- thejob->stopped_progs = 0;
-
- if (inbg) {
- /* we don't wait for background thejobs to return -- append it
- to the list of backgrounded thejobs and leave it alone */
- printf("[%d] %d\n", thejob->jobid,
- newjob->progs[newjob->num_progs - 1].pid);
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- last_bg_pid=newjob->progs[newjob->num_progs - 1].pid;
-#endif
- } else {
- newjob->job_list->fg = thejob;
-
- /* move the new process group into the foreground */
- /* suppress messages when run from /linuxrc mag@sysgo.de */
- if (tcsetpgrp(0, newjob->pgrp) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
- }
-}
-
-static int run_command(struct job *newjob, int inbg, int outpipe[2])
-{
- /* struct job *thejob; */
- int i;
- int nextin, nextout;
- int pipefds[2]; /* pipefd[0] is for reading */
- struct built_in_command *x;
- struct child_prog *child;
-
- nextin = 0, nextout = 1;
- for (i = 0; i < newjob->num_progs; i++) {
- child = & (newjob->progs[i]);
-
- if ((i + 1) < newjob->num_progs) {
- if (pipe(pipefds)<0) perror_msg_and_die("pipe");
- nextout = pipefds[1];
- } else {
- if (outpipe[1]!=-1) {
- nextout = outpipe[1];
- } else {
- nextout = 1;
- }
- }
-
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- if (show_x_trace==TRUE) {
- int j;
- fputc('+', stderr);
- for (j = 0; child->argv[j]; j++) {
- fputc(' ', stderr);
- fputs(child->argv[j], stderr);
- }
- fputc('\n', stderr);
- }
-#endif
-
- /* Check if the command matches any non-forking builtins,
- * but only if this is a simple command.
- * Non-forking builtins within pipes have to fork anyway,
- * and are handled in pseudo_exec. "echo foo | read bar"
- * is doomed to failure, and doesn't work on bash, either.
- */
- if (newjob->num_progs == 1) {
- for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
- int squirrel[] = {-1, -1, -1};
- int rcode;
- setup_redirects(child, squirrel);
- rcode = x->function(child);
- restore_redirects(squirrel);
- return rcode;
- }
- }
- }
-
- if (!(child->pid = fork())) {
- signal(SIGTTOU, SIG_DFL);
-
- close_all();
-
- if (outpipe[1]!=-1) {
- close(outpipe[0]);
- }
- if (nextin != 0) {
- dup2(nextin, 0);
- close(nextin);
- }
-
- if (nextout != 1) {
- dup2(nextout, 1);
- dup2(nextout, 2); /* Really? */
- close(nextout);
- close(pipefds[0]);
- }
-
- /* explicit redirects override pipes */
- setup_redirects(child,NULL);
-
- pseudo_exec(child);
- }
- if (outpipe[1]!=-1) {
- close(outpipe[1]);
- }
-
- /* put our child in the process group whose leader is the
- first process in this pipe */
- setpgid(child->pid, newjob->progs[0].pid);
- if (nextin != 0)
- close(nextin);
- if (nextout != 1)
- close(nextout);
-
- /* If there isn't another process, nextin is garbage
- but it doesn't matter */
- nextin = pipefds[0];
- }
-
- newjob->pgrp = newjob->progs[0].pid;
-
- insert_job(newjob, inbg);
-
- return 0;
-}
-
-static int busy_loop(FILE * input)
-{
- char *command;
- char *next_command = NULL;
- struct job newjob;
- pid_t parent_pgrp;
- int i;
- int inbg;
- int status;
- newjob.job_list = &job_list;
- newjob.job_context = DEFAULT_CONTEXT;
-
- /* save current owner of TTY so we can restore it on exit */
- parent_pgrp = tcgetpgrp(0);
-
- command = (char *) xcalloc(BUFSIZ, sizeof(char));
-
- /* don't pay any attention to this signal; it just confuses
- things and isn't really meant for shells anyway */
- signal(SIGTTOU, SIG_IGN);
-
- while (1) {
- if (!job_list.fg) {
- /* no job is in the foreground */
-
- /* see if any background processes have exited */
- checkjobs(&job_list);
-
- if (!next_command) {
- if (get_command(input, command))
- break;
- next_command = command;
- }
-
- if (expand_arguments(next_command) == FALSE) {
- free(command);
- command = (char *) xcalloc(BUFSIZ, sizeof(char));
- next_command = NULL;
- continue;
- }
-
- if (!parse_command(&next_command, &newjob, &inbg) &&
- newjob.num_progs) {
- int pipefds[2] = {-1,-1};
- debug_printf( "job=%p fed to run_command by busy_loop()'\n",
- &newjob);
- run_command(&newjob, inbg, pipefds);
- }
- else {
- free(command);
- command = (char *) xcalloc(BUFSIZ, sizeof(char));
- next_command = NULL;
- }
- } else {
- /* a job is running in the foreground; wait for it */
- i = 0;
- while (!job_list.fg->progs[i].pid ||
- job_list.fg->progs[i].is_stopped == 1) i++;
-
- if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED)<0)
- perror_msg_and_die("waitpid(%d)",job_list.fg->progs[i].pid);
-
- if (WIFEXITED(status) || WIFSIGNALED(status)) {
- /* the child exited */
- job_list.fg->running_progs--;
- job_list.fg->progs[i].pid = 0;
-
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- last_return_code=WEXITSTATUS(status);
- debug_printf("'%s' exited -- return code %d\n",
- job_list.fg->text, last_return_code);
-#endif
- if (!job_list.fg->running_progs) {
- /* child exited */
- remove_job(&job_list, job_list.fg);
- job_list.fg = NULL;
- }
- } else {
- /* the child was stopped */
- job_list.fg->stopped_progs++;
- job_list.fg->progs[i].is_stopped = 1;
-
- if (job_list.fg->stopped_progs == job_list.fg->running_progs) {
- printf("\n" JOB_STATUS_FORMAT, job_list.fg->jobid,
- "Stopped", job_list.fg->text);
- job_list.fg = NULL;
- }
- }
-
- if (!job_list.fg) {
- /* move the shell to the foreground */
- /* suppress messages when run from /linuxrc mag@sysgo.de */
- if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY)
- perror_msg("tcsetpgrp");
- }
- }
- }
- free(command);
-
- /* return controlling TTY back to parent process group before exiting */
- if (tcsetpgrp(0, parent_pgrp))
- perror_msg("tcsetpgrp");
-
- /* return exit status if called with "-c" */
- if (input == NULL && WIFEXITED(status))
- return WEXITSTATUS(status);
-
- return 0;
-}
-
-
-#ifdef BB_FEATURE_CLEAN_UP
-void free_memory(void)
-{
- if (cwd) {
- free(cwd);
- cwd = NULL;
- }
- if (local_pending_command)
- free(local_pending_command);
-
- if (job_list.fg && !job_list.fg->running_progs) {
- remove_job(&job_list, job_list.fg);
- }
-}
-#endif
-
-
-int shell_main(int argc_l, char **argv_l)
-{
- int opt, interactive=FALSE;
- FILE *input = stdin;
- argc = argc_l;
- argv = argv_l;
-
- /* These variables need re-initializing when recursing */
- shell_context = 0;
- local_pending_command = NULL;
- close_me_head = NULL;
- job_list.head = NULL;
- job_list.fg = NULL;
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- last_bg_pid=1;
- last_return_code=1;
- show_x_trace=FALSE;
-#endif
-
- if (argv[0] && argv[0][0] == '-') {
- FILE *prof_input;
- prof_input = fopen("/etc/profile", "r");
- if (!prof_input) {
- printf( "Couldn't open file '/etc/profile'\n");
- } else {
- int tmp_fd = fileno(prof_input);
- mark_open(tmp_fd);
- /* Now run the file */
- busy_loop(prof_input);
- fclose(prof_input);
- mark_closed(tmp_fd);
- }
- }
-
- while ((opt = getopt(argc_l, argv_l, "cxi")) > 0) {
- switch (opt) {
- case 'c':
- input = NULL;
- if (local_pending_command != 0)
- error_msg_and_die("multiple -c arguments");
- local_pending_command = xstrdup(argv[optind]);
- optind++;
- argv = argv+optind;
- break;
-#ifdef BB_FEATURE_SH_ENVIRONMENT
- case 'x':
- show_x_trace = TRUE;
- break;
-#endif
- case 'i':
- interactive = TRUE;
- break;
- default:
- show_usage();
- }
- }
- /* A shell is interactive if the `-i' flag was given, or if all of
- * the following conditions are met:
- * no -c command
- * no arguments remaining or the -s flag given
- * standard input is a terminal
- * standard output is a terminal
- * Refer to Posix.2, the description of the `sh' utility. */
- if (argv[optind]==NULL && input==stdin &&
- isatty(fileno(stdin)) && isatty(fileno(stdout))) {
- interactive=TRUE;
- }
- if (interactive==TRUE) {
- //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
- /* Looks like they want an interactive shell */
- printf( "\n\n" BB_BANNER " Built-in shell (lash)\n");
- printf( "Enter 'help' for a list of built-in commands.\n\n");
- } else if (local_pending_command==NULL) {
- //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
- input = xfopen(argv[optind], "r");
- mark_open(fileno(input)); /* be lazy, never mark this closed */
- }
-
- /* initialize the cwd -- this is never freed...*/
- cwd = xgetcwd(0);
-
-#ifdef BB_FEATURE_CLEAN_UP
- atexit(free_memory);
-#endif
-
-#ifdef BB_FEATURE_COMMAND_EDITING
- cmdedit_set_initial_prompt();
-#else
- PS1 = NULL;
-#endif
-
- return (busy_loop(input));
-}
-
diff --git a/shell/hush.c b/shell/hush.c
new file mode 100644
index 0000000..f2a4ea4
--- /dev/null
+++ b/shell/hush.c
@@ -0,0 +1,2191 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * sh.c -- a prototype Bourne shell grammar parser
+ * Intended to follow the original Thompson and Ritchie
+ * "small and simple is beautiful" philosophy, which
+ * incidentally is a good match to today's BusyBox.
+ *
+ * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
+ *
+ * Credits:
+ * The parser routines proper are all original material, first
+ * written Dec 2000 and Jan 2001 by Larry Doolittle.
+ * The execution engine, the builtins, and much of the underlying
+ * support has been adapted from busybox-0.49pre's lash,
+ * which is Copyright (C) 2000 by Lineo, Inc., and
+ * written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
+ * That, in turn, is based in part on ladsh.c, by Michael K. Johnson and
+ * Erik W. Troan, which they placed in the public domain. I don't know
+ * how much of the Johnson/Troan code has survived the repeated rewrites.
+ * Other credits:
+ * simple_itoa() was lifted from boa-0.93.15
+ * b_addchr() derived from similar w_addchar function in glibc-2.2
+ * setup_redirect(), redirect_opt_num(), and big chunks of main()
+ * and many builtins derived from contributions by Erik Andersen
+ * miscellaneous bugfixes from Matt Kraai
+ *
+ * There are two big (and related) architecture differences between
+ * this parser and the lash parser. One is that this version is
+ * actually designed from the ground up to understand nearly all
+ * of the Bourne grammar. The second, consequential change is that
+ * the parser and input reader have been turned inside out. Now,
+ * the parser is in control, and asks for input as needed. The old
+ * way had the input reader in control, and it asked for parsing to
+ * take place as needed. The new way makes it much easier to properly
+ * handle the recursion implicit in the various substitutions, especially
+ * across continuation lines.
+ *
+ * Bash grammar not implemented: (how many of these were in original sh?)
+ * $@ (those sure look like weird quoting rules)
+ * $_
+ * ! negation operator for pipes
+ * &> and >& redirection of stdout+stderr
+ * Brace Expansion
+ * Tilde Expansion
+ * fancy forms of Parameter Expansion
+ * Arithmetic Expansion
+ * <(list) and >(list) Process Substitution
+ * reserved words: if, then, elif, else, fi, while, until, for,
+ * do, done, case
+ * Here Documents ( << word )
+ * Functions
+ * Major bugs:
+ * job handling woefully incomplete and buggy
+ * reserved word execution woefully incomplete and buggy
+ * incomplete reserved word sequence doesn't request more lines of input
+ * to-do:
+ * port selected bugfixes from post-0.49 busybox lash
+ * finish implementing reserved words
+ * handle children going into background
+ * clean up recognition of null pipes
+ * have builtin_exec set flag to avoid restore_redirects
+ * figure out if "echo foo}" is fixable
+ * check setting of global_argc and global_argv
+ * control-C handling, probably with longjmp
+ * VAR=value prefix for simple commands
+ * follow IFS rules more precisely, including update semantics
+ * write builtin_eval, builtin_ulimit, builtin_umask
+ * figure out what to do with backslash-newline
+ * explain why we use signal instead of sigaction
+ * propagate syntax errors, die on resource errors?
+ * continuation lines, both explicit and implicit - done?
+ * memory leak finding and plugging - done?
+ * more testing, especially quoting rules and redirection
+ * maybe change map[] to use 2-bit entries
+ * (eventually) remove all the printf's
+ * more integration with BusyBox: prompts, cmdedit, applets
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <ctype.h> /* isalpha, isdigit */
+#include <unistd.h> /* getpid */
+#include <stdlib.h> /* getenv, atoi */
+#include <string.h> /* strchr */
+#include <stdio.h> /* popen etc. */
+#include <glob.h> /* glob, of course */
+#include <stdarg.h> /* va_list */
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h> /* should be pretty obvious */
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+
+/* #include <dmalloc.h> */
+/* #define DEBUG_SHELL */
+
+#ifdef BB_VER
+#include "busybox.h"
+#include "cmdedit.h"
+#else
+/* in place of #include "busybox.h"; much of this is indeed
+ * pasted in from the copy of busybox.h in busybox-0.49pre */
+
+#define xrealloc realloc
+#define applet_name "hush"
+#define shell_main main
+
+extern void *xmalloc(size_t size)
+{
+ void *ptr = malloc(size);
+
+ if (!ptr) {
+ fprintf(stderr, "memory_exhausted\n");
+ exit (EXIT_FAILURE);
+ }
+ return ptr;
+}
+
+extern void usage(const char *usage)
+{
+ fprintf(stderr, "Usage: %s\n", usage);
+ exit(EXIT_FAILURE);
+}
+
+static void verror_msg(const char *s, va_list p)
+{
+ fflush(stdout);
+ fprintf(stderr, "%s: ", applet_name);
+ vfprintf(stderr, s, p);
+ fflush(stderr);
+}
+
+extern void error_msg(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ verror_msg(s, p);
+ va_end(p);
+}
+
+extern void error_msg_and_die(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ verror_msg(s, p);
+ va_end(p);
+ exit(EXIT_FAILURE);
+}
+
+static void vperror_msg(const char *s, va_list p)
+{
+ fflush(stdout);
+ fprintf(stderr, "%s: ", applet_name);
+ if (s && *s) {
+ vfprintf(stderr, s, p);
+ fputs(": ", stderr);
+ }
+ fprintf(stderr, "%s\n", strerror(errno));
+ fflush(stderr);
+}
+
+extern void perror_msg(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ vperror_msg(s, p);
+ va_end(p);
+}
+
+extern void perror_msg_and_die(const char *s, ...)
+{
+ va_list p;
+
+ va_start(p, s);
+ vperror_msg(s, p);
+ va_end(p);
+ exit(EXIT_FAILURE);
+}
+
+FILE *xfopen(const char *path, const char *mode)
+{
+ FILE *fp;
+ if ((fp = fopen(path, mode)) == NULL)
+ perror_msg_and_die(path);
+ return fp;
+}
+#endif /* of busybox.h replacement */
+
+typedef enum {
+ REDIRECT_INPUT = 1,
+ REDIRECT_OVERWRITE = 2,
+ REDIRECT_APPEND = 3,
+ REDIRECT_HEREIS = 4,
+ REDIRECT_IO = 5
+} redir_type;
+
+/* The descrip member of this structure is only used to make debugging
+ * output pretty */
+struct {int mode; int default_fd; char *descrip;} redir_table[] = {
+ { 0, 0, "()" },
+ { O_RDONLY, 0, "<" },
+ { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
+ { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
+ { O_RDONLY, -1, "<<" },
+ { O_RDWR, 1, "<>" }
+};
+
+typedef enum {
+ PIPE_SEQ = 1,
+ PIPE_AND = 2,
+ PIPE_OR = 3,
+ PIPE_BG = 4,
+} pipe_style;
+
+/* might eventually control execution */
+typedef enum {
+ RES_NONE = 0,
+ RES_IF = 1,
+ RES_THEN = 2,
+ RES_ELIF = 3,
+ RES_ELSE = 4,
+ RES_FI = 5,
+ RES_FOR = 6,
+ RES_WHILE = 7,
+ RES_UNTIL = 8,
+ RES_DO = 9,
+ RES_DONE = 10,
+ RES_XXXX = 11
+} reserved_style;
+#define FLAG_END (1<<RES_NONE)
+#define FLAG_IF (1<<RES_IF)
+#define FLAG_THEN (1<<RES_THEN)
+#define FLAG_ELIF (1<<RES_ELIF)
+#define FLAG_ELSE (1<<RES_ELSE)
+#define FLAG_FI (1<<RES_FI)
+#define FLAG_FOR (1<<RES_FOR)
+#define FLAG_WHILE (1<<RES_WHILE)
+#define FLAG_UNTIL (1<<RES_UNTIL)
+#define FLAG_DO (1<<RES_DO)
+#define FLAG_DONE (1<<RES_DONE)
+#define FLAG_START (1<<RES_XXXX)
+
+/* This holds pointers to the various results of parsing */
+struct p_context {
+ struct child_prog *child;
+ struct pipe *list_head;
+ struct pipe *pipe;
+ struct redir_struct *pending_redirect;
+ reserved_style w;
+ int old_flag; /* for figuring out valid reserved words */
+ struct p_context *stack;
+ /* How about quoting status? */
+};
+
+struct redir_struct {
+ redir_type type; /* type of redirection */
+ int fd; /* file descriptor being redirected */
+ int dup; /* -1, or file descriptor being duplicated */
+ struct redir_struct *next; /* pointer to the next redirect in the list */
+ glob_t word; /* *word.gl_pathv is the filename */
+};
+
+struct child_prog {
+ pid_t pid; /* 0 if exited */
+ char **argv; /* program name and arguments */
+ struct pipe *group; /* if non-NULL, first in group or subshell */
+ int subshell; /* flag, non-zero if group must be forked */
+ struct redir_struct *redirects; /* I/O redirections */
+ glob_t glob_result; /* result of parameter globbing */
+ int is_stopped; /* is the program currently running? */
+ struct pipe *family; /* pointer back to the child's parent pipe */
+};
+
+struct pipe {
+ int jobid; /* job number */
+ int num_progs; /* total number of programs in job */
+ int running_progs; /* number of programs running */
+ char *text; /* name of job */
+ char *cmdbuf; /* buffer various argv's point into */
+ pid_t pgrp; /* process group ID for the job */
+ struct child_prog *progs; /* array of commands in pipe */
+ struct pipe *next; /* to track background commands */
+ int stopped_progs; /* number of programs alive, but stopped */
+ int job_context; /* bitmask defining current context */
+ pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
+ reserved_style r_mode; /* supports if, for, while, until */
+ struct jobset *job_list;
+};
+
+struct jobset {
+ struct pipe *head; /* head of list of running jobs */
+ struct pipe *fg; /* current foreground job */
+};
+
+struct close_me {
+ int fd;
+ struct close_me *next;
+};
+
+/* globals, connect us to the outside world
+ * the first three support $?, $#, and $1 */
+char **global_argv;
+unsigned int global_argc;
+unsigned int last_return_code;
+extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
+
+/* Variables we export */
+unsigned int shell_context; /* Used in cmdedit.c to reset the
+ * context when someone hits ^C */
+
+/* "globals" within this file */
+static char *ifs=NULL;
+static char map[256];
+static int fake_mode=0;
+static int interactive=0;
+static struct close_me *close_me_head = NULL;
+static char *cwd;
+static struct jobset job_list = { NULL, NULL };
+static unsigned int last_bg_pid=0;
+static char *PS1;
+static char *PS2 = "> ";
+
+#define B_CHUNK (100)
+#define B_NOSPAC 1
+#define MAX_LINE 256 /* for cwd */
+#define MAX_READ 256 /* for builtin_read */
+
+typedef struct {
+ char *data;
+ int length;
+ int maxlen;
+ int quote;
+ int nonnull;
+} o_string;
+#define NULL_O_STRING {NULL,0,0,0,0}
+/* used for initialization:
+ o_string foo = NULL_O_STRING; */
+
+/* I can almost use ordinary FILE *. Is open_memstream() universally
+ * available? Where is it documented? */
+struct in_str {
+ const char *p;
+ int __promptme;
+ int promptmode;
+ FILE *file;
+ int (*get) (struct in_str *);
+ int (*peek) (struct in_str *);
+};
+#define b_getch(input) ((input)->get(input))
+#define b_peek(input) ((input)->peek(input))
+
+#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
+
+struct built_in_command {
+ char *cmd; /* name */
+ char *descr; /* description */
+ int (*function) (struct child_prog *); /* function ptr */
+};
+
+/* belongs in busybox.h */
+static inline int max(int a, int b) {
+ return (a>b)?a:b;
+}
+
+/* This should be in utility.c */
+#ifdef DEBUG_SHELL
+static void debug_printf(const char *format, ...)
+{
+ va_list args;
+ va_start(args, format);
+ vfprintf(stderr, format, args);
+ va_end(args);
+}
+#else
+static void debug_printf(const char *format, ...) { }
+#endif
+#define final_printf debug_printf
+
+void __syntax(char *file, int line) {
+ fprintf(stderr,"syntax error %s:%d\n",file,line);
+}
+#define syntax() __syntax(__FILE__, __LINE__)
+
+/* Index of subroutines: */
+/* function prototypes for builtins */
+static int builtin_cd(struct child_prog *child);
+static int builtin_env(struct child_prog *child);
+static int builtin_exec(struct child_prog *child);
+static int builtin_exit(struct child_prog *child);
+static int builtin_export(struct child_prog *child);
+static int builtin_fg_bg(struct child_prog *child);
+static int builtin_help(struct child_prog *child);
+static int builtin_jobs(struct child_prog *child);
+static int builtin_pwd(struct child_prog *child);
+static int builtin_read(struct child_prog *child);
+static int builtin_shift(struct child_prog *child);
+static int builtin_source(struct child_prog *child);
+static int builtin_ulimit(struct child_prog *child);
+static int builtin_umask(struct child_prog *child);
+static int builtin_unset(struct child_prog *child);
+/* o_string manipulation: */
+static int b_check_space(o_string *o, int len);
+static int b_addchr(o_string *o, int ch);
+static void b_reset(o_string *o);
+static int b_addqchr(o_string *o, int ch, int quote);
+static int b_adduint(o_string *o, unsigned int i);
+/* in_str manipulations: */
+static int static_get(struct in_str *i);
+static int static_peek(struct in_str *i);
+static int file_get(struct in_str *i);
+static int file_peek(struct in_str *i);
+static void setup_file_in_str(struct in_str *i, FILE *f);
+static void setup_string_in_str(struct in_str *i, const char *s);
+/* close_me manipulations: */
+static void mark_open(int fd);
+static void mark_closed(int fd);
+static void close_all();
+/* "run" the final data structures: */
+static char *indenter(int i);
+static int run_list_test(struct pipe *head, int indent);
+static int run_pipe_test(struct pipe *pi, int indent);
+/* really run the final data structures: */
+static int setup_redirects(struct child_prog *prog, int squirrel[]);
+static int pipe_wait(struct pipe *pi);
+static int run_list_real(struct pipe *pi);
+static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn));
+static int run_pipe_real(struct pipe *pi);
+/* extended glob support: */
+static int globhack(const char *src, int flags, glob_t *pglob);
+static int glob_needed(const char *s);
+static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* data structure manipulation: */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
+static void initialize_context(struct p_context *ctx);
+static int done_word(o_string *dest, struct p_context *ctx);
+static int done_command(struct p_context *ctx);
+static int done_pipe(struct p_context *ctx, pipe_style type);
+/* primary string parsing: */
+static int redirect_dup_num(struct in_str *input);
+static int redirect_opt_num(o_string *o);
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
+static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
+static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src);
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
+static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
+static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
+/* setup: */
+static int parse_stream_outer(struct in_str *inp);
+static int parse_string_outer(const char *s);
+static int parse_file_outer(FILE *f);
+
+/* Table of built-in functions. They can be forked or not, depending on
+ * context: within pipes, they fork. As simple commands, they do not.
+ * When used in non-forking context, they can change global variables
+ * in the parent shell process. If forked, of course they can not.
+ * For example, 'unset foo | whatever' will parse and run, but foo will
+ * still be set at the end. */
+static struct built_in_command bltins[] = {
+ {"bg", "Resume a job in the background", builtin_fg_bg},
+ {"cd", "Change working directory", builtin_cd},
+ {"env", "Print all environment variables", builtin_env},
+ {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec},
+ {"exit", "Exit from shell()", builtin_exit},
+ {"export", "Set environment variable", builtin_export},
+ {"fg", "Bring job into the foreground", builtin_fg_bg},
+ {"jobs", "Lists the active jobs", builtin_jobs},
+ {"pwd", "Print current directory", builtin_pwd},
+ {"read", "Input environment variable", builtin_read},
+ {"shift", "Shift positional parameters", builtin_shift},
+ {"ulimit","Controls resource limits", builtin_ulimit},
+ {"umask","Sets file creation mask", builtin_umask},
+ {"unset", "Unset environment variable", builtin_unset},
+ {".", "Source-in and run commands in a file", builtin_source},
+ {"help", "List shell built-in commands", builtin_help},
+ {NULL, NULL, NULL}
+};
+
+/* built-in 'cd <path>' handler */
+static int builtin_cd(struct child_prog *child)
+{
+ char *newdir;
+ if (child->argv[1] == NULL)
+ newdir = getenv("HOME");
+ else
+ newdir = child->argv[1];
+ if (chdir(newdir)) {
+ printf("cd: %s: %s\n", newdir, strerror(errno));
+ return EXIT_FAILURE;
+ }
+ getcwd(cwd, sizeof(char)*MAX_LINE);
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'env' handler */
+static int builtin_env(struct child_prog *dummy)
+{
+ char **e = environ;
+ if (e == NULL) return EXIT_FAILURE;
+ for (; *e; e++) {
+ puts(*e);
+ }
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'exec' handler */
+static int builtin_exec(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ return EXIT_SUCCESS; /* Really? */
+ child->argv++;
+ pseudo_exec(child);
+ /* never returns */
+}
+
+/* built-in 'exit' handler */
+static int builtin_exit(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ exit(EXIT_SUCCESS);
+ exit (atoi(child->argv[1]));
+}
+
+/* built-in 'export VAR=value' handler */
+static int builtin_export(struct child_prog *child)
+{
+ int res;
+
+ if (child->argv[1] == NULL) {
+ return (builtin_env(child));
+ }
+ res = putenv(child->argv[1]);
+ if (res)
+ fprintf(stderr, "export: %s\n", strerror(errno));
+ return (res);
+}
+
+/* built-in 'fg' and 'bg' handler */
+static int builtin_fg_bg(struct child_prog *child)
+{
+ int i, jobNum;
+ struct pipe *job=NULL;
+
+ if (!child->argv[1] || child->argv[2]) {
+ error_msg("%s: exactly one argument is expected\n",
+ child->argv[0]);
+ return EXIT_FAILURE;
+ }
+
+ if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
+ error_msg("%s: bad argument '%s'\n",
+ child->argv[0], child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ for (job = child->family->job_list->head; job; job = job->next) {
+ if (job->jobid == jobNum) {
+ break;
+ }
+ }
+
+ if (!job) {
+ error_msg("%s: unknown job %d\n",
+ child->argv[0], jobNum);
+ return EXIT_FAILURE;
+ }
+
+ if (*child->argv[0] == 'f') {
+ /* Make this job the foreground job */
+ /* suppress messages when run from /linuxrc mag@sysgo.de */
+ if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ child->family->job_list->fg = job;
+ }
+
+ /* Restart the processes in the job */
+ for (i = 0; i < job->num_progs; i++)
+ job->progs[i].is_stopped = 0;
+
+ kill(-job->pgrp, SIGCONT);
+
+ job->stopped_progs = 0;
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'help' handler */
+static int builtin_help(struct child_prog *dummy)
+{
+ struct built_in_command *x;
+
+ printf("\nBuilt-in commands:\n");
+ printf("-------------------\n");
+ for (x = bltins; x->cmd; x++) {
+ if (x->descr==NULL)
+ continue;
+ printf("%s\t%s\n", x->cmd, x->descr);
+ }
+ printf("\n\n");
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'jobs' handler */
+static int builtin_jobs(struct child_prog *child)
+{
+ struct pipe *job;
+ char *status_string;
+
+ for (job = child->family->job_list->head; job; job = job->next) {
+ if (job->running_progs == job->stopped_progs)
+ status_string = "Stopped";
+ else
+ status_string = "Running";
+ printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
+ }
+ return EXIT_SUCCESS;
+}
+
+
+/* built-in 'pwd' handler */
+static int builtin_pwd(struct child_prog *dummy)
+{
+ getcwd(cwd, MAX_LINE);
+ puts(cwd);
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'read VAR' handler */
+static int builtin_read(struct child_prog *child)
+{
+ int res = 0, len, newlen;
+ char *s;
+ char string[MAX_READ];
+
+ if (child->argv[1]) {
+ /* argument (VAR) given: put "VAR=" into buffer */
+ strcpy(string, child->argv[1]);
+ len = strlen(string);
+ string[len++] = '=';
+ string[len] = '\0';
+ /* XXX would it be better to go through in_str? */
+ fgets(&string[len], sizeof(string) - len, stdin); /* read string */
+ newlen = strlen(string);
+ if(newlen > len)
+ string[--newlen] = '\0'; /* chomp trailing newline */
+ /*
+ ** string should now contain "VAR=<value>"
+ ** copy it (putenv() won't do that, so we must make sure
+ ** the string resides in a static buffer!)
+ */
+ res = -1;
+ if((s = strdup(string)))
+ res = putenv(s);
+ if (res)
+ fprintf(stderr, "read: %s\n", strerror(errno));
+ }
+ else
+ fgets(string, sizeof(string), stdin);
+
+ return (res);
+}
+
+/* Built-in 'shift' handler */
+static int builtin_shift(struct child_prog *child)
+{
+ int n=1;
+ if (child->argv[1]) {
+ n=atoi(child->argv[1]);
+ }
+ if (n>=0 && n<global_argc) {
+ /* XXX This probably breaks $0 */
+ global_argc -= n;
+ global_argv += n;
+ return EXIT_SUCCESS;
+ } else {
+ return EXIT_FAILURE;
+ }
+}
+
+/* Built-in '.' handler (read-in and execute commands from file) */
+static int builtin_source(struct child_prog *child)
+{
+ FILE *input;
+ int status;
+
+ if (child->argv[1] == NULL)
+ return EXIT_FAILURE;
+
+ /* XXX search through $PATH is missing */
+ input = fopen(child->argv[1], "r");
+ if (!input) {
+ fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ /* Now run the file */
+ /* XXX argv and argc are broken; need to save old global_argv
+ * (pointer only is OK!) on this stack frame,
+ * set global_argv=child->argv+1, recurse, and restore. */
+ mark_open(fileno(input));
+ status = parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ return (status);
+}
+
+static int builtin_ulimit(struct child_prog *child)
+{
+ printf("builtin_ulimit not written\n");
+ return EXIT_FAILURE;
+}
+
+static int builtin_umask(struct child_prog *child)
+{
+ printf("builtin_umask not written\n");
+ return EXIT_FAILURE;
+}
+
+/* built-in 'unset VAR' handler */
+static int builtin_unset(struct child_prog *child)
+{
+ if (child->argv[1] == NULL) {
+ fprintf(stderr, "unset: parameter required.\n");
+ return EXIT_FAILURE;
+ }
+ unsetenv(child->argv[1]);
+ return EXIT_SUCCESS;
+}
+
+static int b_check_space(o_string *o, int len)
+{
+ /* It would be easy to drop a more restrictive policy
+ * in here, such as setting a maximum string length */
+ if (o->length + len > o->maxlen) {
+ char *old_data = o->data;
+ /* assert (data == NULL || o->maxlen != 0); */
+ o->maxlen += max(2*len, B_CHUNK);
+ o->data = realloc(o->data, 1 + o->maxlen);
+ if (o->data == NULL) {
+ free(old_data);
+ }
+ }
+ return o->data == NULL;
+}
+
+static int b_addchr(o_string *o, int ch)
+{
+ debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
+ if (b_check_space(o, 1)) return B_NOSPAC;
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+ return 0;
+}
+
+static void b_reset(o_string *o)
+{
+ o->length = 0;
+ o->nonnull = 0;
+ if (o->data != NULL) *o->data = '\0';
+}
+
+static void b_free(o_string *o)
+{
+ b_reset(o);
+ if (o->data != NULL) free(o->data);
+ o->data = NULL;
+ o->maxlen = 0;
+}
+
+/* My analysis of quoting semantics tells me that state information
+ * is associated with a destination, not a source.
+ */
+static int b_addqchr(o_string *o, int ch, int quote)
+{
+ if (quote && strchr("*?[\\",ch)) {
+ int rc;
+ rc = b_addchr(o, '\\');
+ if (rc) return rc;
+ }
+ return b_addchr(o, ch);
+}
+
+/* belongs in utility.c */
+char *simple_itoa(unsigned int i)
+{
+ /* 21 digits plus null terminator, good for 64-bit or smaller ints */
+ static char local[22];
+ char *p = &local[21];
+ *p-- = '\0';
+ do {
+ *p-- = '0' + i % 10;
+ i /= 10;
+ } while (i > 0);
+ return p + 1;
+}
+
+static int b_adduint(o_string *o, unsigned int i)
+{
+ int r;
+ char *p = simple_itoa(i);
+ /* no escape checking necessary */
+ do r=b_addchr(o, *p++); while (r==0 && *p);
+ return r;
+}
+
+static int static_get(struct in_str *i)
+{
+ int ch=*i->p++;
+ if (ch=='\0') return EOF;
+ return ch;
+}
+
+static int static_peek(struct in_str *i)
+{
+ return *i->p;
+}
+
+static inline void cmdedit_set_initial_prompt(void)
+{
+#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+ PS1 = NULL;
+#else
+ PS1 = getenv("PS1");
+ if(PS1==0)
+ PS1 = "\\w \\$ ";
+#endif
+}
+
+static inline void setup_prompt_string(int promptmode, char **prompt_str)
+{
+#ifdef BB_FEATURE_SH_SIMPLE_PROMPT
+ /* Set up the prompt */
+ if (promptmode == 1) {
+ if (PS1)
+ free(PS1);
+ PS1=xmalloc(strlen(cwd)+4);
+ sprintf(PS1, "%s %s", cwd, ( geteuid() != 0 ) ? "$ ":"# ");
+ *prompt_str = PS1;
+ } else {
+ *prompt_str = PS2;
+ }
+#else
+ *prompt_str = (promptmode==0)? PS1 : PS2;
+#endif
+}
+
+static void get_user_input(struct in_str *i)
+{
+ char *prompt_str;
+ static char the_command[MAX_LINE];
+
+ setup_prompt_string(i->promptmode, &prompt_str);
+#ifdef BB_FEATURE_COMMAND_EDITING
+ /*
+ ** enable command line editing only while a command line
+ ** is actually being read; otherwise, we'll end up bequeathing
+ ** atexit() handlers and other unwanted stuff to our
+ ** child processes (rob@sysgo.de)
+ */
+ cmdedit_read_input(prompt_str, the_command);
+ cmdedit_terminate();
+#else
+ fputs(prompt_str, stdout);
+ fflush(stdout);
+ the_command[0]=fgetc(i->file);
+ the_command[1]='\0';
+#endif
+ i->p = the_command;
+}
+
+/* This is the magic location that prints prompts
+ * and gets data back from the user */
+static int file_get(struct in_str *i)
+{
+ int ch;
+
+ ch = 0;
+ /* If there is data waiting, eat it up */
+ if (i->p && *i->p) {
+ ch=*i->p++;
+ } else {
+ /* need to double check i->file because we might be doing something
+ * more complicated by now, like sourcing or substituting. */
+ if (i->__promptme && interactive && i->file == stdin) {
+ get_user_input(i);
+ i->promptmode=2;
+ }
+ i->__promptme = 0;
+
+ if (i->p && *i->p) {
+ ch=*i->p++;
+ }
+ debug_printf("b_getch: got a %d\n", ch);
+ }
+ if (ch == '\n') i->__promptme=1;
+ return ch;
+}
+
+/* All the callers guarantee this routine will never be
+ * used right after a newline, so prompting is not needed.
+ */
+static int file_peek(struct in_str *i)
+{
+ if (i->p && *i->p) {
+ return *i->p;
+ } else {
+ static char buffer;
+ buffer = fgetc(i->file);
+ i->p = &buffer;
+ debug_printf("b_peek: got a %d\n", *i->p);
+ return *i->p;
+ }
+}
+
+static void setup_file_in_str(struct in_str *i, FILE *f)
+{
+ i->peek = file_peek;
+ i->get = file_get;
+ i->__promptme=1;
+ i->promptmode=1;
+ i->file = f;
+ i->p = NULL;
+}
+
+static void setup_string_in_str(struct in_str *i, const char *s)
+{
+ i->peek = static_peek;
+ i->get = static_get;
+ i->__promptme=1;
+ i->promptmode=1;
+ i->p = s;
+}
+
+static void mark_open(int fd)
+{
+ struct close_me *new = xmalloc(sizeof(struct close_me));
+ new->fd = fd;
+ new->next = close_me_head;
+ close_me_head = new;
+}
+
+static void mark_closed(int fd)
+{
+ struct close_me *tmp;
+ if (close_me_head == NULL || close_me_head->fd != fd)
+ error_msg_and_die("corrupt close_me");
+ tmp = close_me_head;
+ close_me_head = close_me_head->next;
+ free(tmp);
+}
+
+static void close_all()
+{
+ struct close_me *c;
+ for (c=close_me_head; c; c=c->next) {
+ close(c->fd);
+ }
+ close_me_head = NULL;
+}
+
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct child_prog *prog, int squirrel[])
+{
+ int openfd, mode;
+ struct redir_struct *redir;
+
+ for (redir=prog->redirects; redir; redir=redir->next) {
+ if (redir->dup == -1) {
+ mode=redir_table[redir->type].mode;
+ openfd = open(redir->word.gl_pathv[0], mode, 0666);
+ if (openfd < 0) {
+ /* this could get lost if stderr has been redirected, but
+ bash and ash both lose it as well (though zsh doesn't!) */
+ fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0],
+ strerror(errno));
+ return 1;
+ }
+ } else {
+ openfd = redir->dup;
+ }
+
+ if (openfd != redir->fd) {
+ if (squirrel && redir->fd < 3) {
+ squirrel[redir->fd] = dup(redir->fd);
+ }
+ dup2(openfd, redir->fd);
+ close(openfd);
+ }
+ }
+ return 0;
+}
+
+static void restore_redirects(int squirrel[])
+{
+ int i, fd;
+ for (i=0; i<3; i++) {
+ fd = squirrel[i];
+ if (fd != -1) {
+ /* No error checking. I sure wouldn't know what
+ * to do with an error if I found one! */
+ dup2(fd, i);
+ close(fd);
+ }
+ }
+}
+
+/* XXX this definitely needs some more thought, work, and
+ * cribbing from other shells */
+static int pipe_wait(struct pipe *pi)
+{
+ int rcode=0, i, pid, running, status;
+ running = pi->num_progs;
+ while (running) {
+ pid=waitpid(-1, &status, 0);
+ if (pid < 0) perror_msg_and_die("waitpid");
+ for (i=0; i < pi->num_progs; i++) {
+ if (pi->progs[i].pid == pid) {
+ if (i==pi->num_progs-1) rcode=WEXITSTATUS(status);
+ pi->progs[i].pid = 0;
+ running--;
+ break;
+ }
+ }
+ }
+ return rcode;
+}
+
+/* very simple version for testing */
+static void pseudo_exec(struct child_prog *child)
+{
+ int rcode;
+ struct built_in_command *x;
+ if (child->argv) {
+ /*
+ * Check if the command matches any of the builtins.
+ * Depending on context, this might be redundant. But it's
+ * easier to waste a few CPU cycles than it is to figure out
+ * if this is one of those cases.
+ */
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ debug_printf("builtin exec %s\n", child->argv[0]);
+ exit(x->function(child));
+ }
+ }
+ debug_printf("exec of %s\n",child->argv[0]);
+ execvp(child->argv[0],child->argv);
+ perror("execvp");
+ exit(1);
+ } else if (child->group) {
+ debug_printf("runtime nesting to group\n");
+ interactive=0; /* crucial!!!! */
+ rcode = run_list_real(child->group);
+ /* OK to leak memory by not calling run_list_test,
+ * since this process is about to exit */
+ exit(rcode);
+ } else {
+ /* Can happen. See what bash does with ">foo" by itself. */
+ debug_printf("trying to pseudo_exec null command\n");
+ exit(EXIT_SUCCESS);
+ }
+}
+
+/* run_pipe_real() starts all the jobs, but doesn't wait for anything
+ * to finish. See pipe_wait().
+ *
+ * return code is normally -1, when the caller has to wait for children
+ * to finish to determine the exit status of the pipe. If the pipe
+ * is a simple builtin command, however, the action is done by the
+ * time run_pipe_real returns, and the exit code is provided as the
+ * return value.
+ *
+ * The input of the pipe is always stdin, the output is always
+ * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
+ * because it tries to avoid running the command substitution in
+ * subshell, when that is in fact necessary. The subshell process
+ * now has its stdout directed to the input of the appropriate pipe,
+ * so this routine is noticeably simpler.
+ */
+static int run_pipe_real(struct pipe *pi)
+{
+ int i;
+ int nextin, nextout;
+ int pipefds[2]; /* pipefds[0] is for reading */
+ struct child_prog *child;
+ struct built_in_command *x;
+
+ nextin = 0;
+ pi->pgrp = 0;
+
+ /* Check if this is a simple builtin (not part of a pipe).
+ * Builtins within pipes have to fork anyway, and are handled in
+ * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
+ */
+ if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
+ child = & (pi->progs[0]);
+ if (child->group && ! child->subshell) {
+ int squirrel[] = {-1, -1, -1};
+ int rcode;
+ debug_printf("non-subshell grouping\n");
+ setup_redirects(child, squirrel);
+ /* XXX could we merge code with following builtin case,
+ * by creating a pseudo builtin that calls run_list_real? */
+ rcode = run_list_real(child->group);
+ restore_redirects(squirrel);
+ return rcode;
+ }
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ int squirrel[] = {-1, -1, -1};
+ int rcode;
+ debug_printf("builtin inline %s\n", child->argv[0]);
+ /* XXX setup_redirects acts on file descriptors, not FILEs.
+ * This is perfect for work that comes after exec().
+ * Is it really safe for inline use? Experimentally,
+ * things seem to work with glibc. */
+ setup_redirects(child, squirrel);
+ rcode = x->function(child);
+ restore_redirects(squirrel);
+ return rcode;
+ }
+ }
+ }
+
+ for (i = 0; i < pi->num_progs; i++) {
+ child = & (pi->progs[i]);
+
+ /* pipes are inserted between pairs of commands */
+ if ((i + 1) < pi->num_progs) {
+ if (pipe(pipefds)<0) perror_msg_and_die("pipe");
+ nextout = pipefds[1];
+ } else {
+ nextout=1;
+ pipefds[0] = -1;
+ }
+
+ /* XXX test for failed fork()? */
+ if (!(child->pid = fork())) {
+ close_all();
+
+ if (nextin != 0) {
+ dup2(nextin, 0);
+ close(nextin);
+ }
+ if (nextout != 1) {
+ dup2(nextout, 1);
+ close(nextout);
+ }
+ if (pipefds[0]!=-1) {
+ close(pipefds[0]); /* opposite end of our output pipe */
+ }
+
+ /* Like bash, explicit redirects override pipes,
+ * and the pipe fd is available for dup'ing. */
+ setup_redirects(child,NULL);
+
+ pseudo_exec(child);
+ }
+ if (interactive) {
+ /* Put our child in the process group whose leader is the
+ * first process in this pipe. */
+ if (pi->pgrp==0) {
+ pi->pgrp = child->pid;
+ }
+ /* Don't check for errors. The child may be dead already,
+ * in which case setpgid returns error code EACCES. */
+ setpgid(child->pid, pi->pgrp);
+ }
+ /* In the non-interactive case, do nothing. Leave the children
+ * with the process group that they inherited from us. */
+
+ if (nextin != 0)
+ close(nextin);
+ if (nextout != 1)
+ close(nextout);
+
+ /* If there isn't another process, nextin is garbage
+ but it doesn't matter */
+ nextin = pipefds[0];
+ }
+ return -1;
+}
+
+static int run_list_real(struct pipe *pi)
+{
+ int rcode=0;
+ int if_code=0, next_if_code=0; /* need double-buffer to handle elif */
+ reserved_style rmode=RES_NONE;
+ for (;pi;pi=pi->next) {
+ rmode = pi->r_mode;
+ debug_printf("rmode=%d if_code=%d next_if_code=%d\n", rmode, if_code, next_if_code);
+ if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code;
+ if (rmode == RES_THEN && if_code) continue;
+ if (rmode == RES_ELSE && !if_code) continue;
+ if (rmode == RES_ELIF && !if_code) continue;
+ if (pi->num_progs == 0) break;
+ rcode = run_pipe_real(pi);
+ if (rcode!=-1) {
+ /* We only ran a builtin: rcode was set by the return value
+ * of run_pipe_real(), and we don't need to wait for anything. */
+ } else if (pi->followup==PIPE_BG) {
+ /* XXX check bash's behavior with nontrivial pipes */
+ /* XXX compute jobid */
+ /* XXX what does bash do with attempts to background builtins? */
+ printf("[%d] %d\n", pi->jobid, pi->pgrp);
+ last_bg_pid = pi->pgrp;
+ rcode = EXIT_SUCCESS;
+ } else {
+ if (interactive) {
+ /* move the new process group into the foreground */
+ /* suppress messages when run from /linuxrc mag@sysgo.de */
+ signal(SIGTTIN, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ rcode = pipe_wait(pi);
+ if (tcsetpgrp(0, getpid()) && errno != ENOTTY)
+ perror_msg("tcsetpgrp");
+ signal(SIGTTIN, SIG_DFL);
+ signal(SIGTTOU, SIG_DFL);
+ } else {
+ rcode = pipe_wait(pi);
+ }
+ }
+ last_return_code=rcode;
+ if ( rmode == RES_IF || rmode == RES_ELIF )
+ next_if_code=rcode; /* can be overwritten a number of times */
+ if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) ||
+ (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) )
+ return rcode; /* XXX broken if list is part of if/then/else */
+ }
+ return rcode;
+}
+
+/* broken, of course, but OK for testing */
+static char *indenter(int i)
+{
+ static char blanks[]=" ";
+ return &blanks[sizeof(blanks)-i-1];
+}
+
+/* return code is the exit status of the pipe */
+static int run_pipe_test(struct pipe *pi, int indent)
+{
+ char **p;
+ struct child_prog *child;
+ struct redir_struct *r, *rnext;
+ int a, i, ret_code=0;
+ char *ind = indenter(indent);
+ final_printf("%s run pipe: (pid %d)\n",ind,getpid());
+ for (i=0; i<pi->num_progs; i++) {
+ child = &pi->progs[i];
+ final_printf("%s command %d:\n",ind,i);
+ if (child->argv) {
+ for (a=0,p=child->argv; *p; a++,p++) {
+ final_printf("%s argv[%d] = %s\n",ind,a,*p);
+ }
+ globfree(&child->glob_result);
+ child->argv=NULL;
+ } else if (child->group) {
+ final_printf("%s begin group (subshell:%d)\n",ind, child->subshell);
+ ret_code = run_list_test(child->group,indent+3);
+ final_printf("%s end group\n",ind);
+ } else {
+ final_printf("%s (nil)\n",ind);
+ }
+ for (r=child->redirects; r; r=rnext) {
+ final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip);
+ if (r->dup == -1) {
+ final_printf(" %s\n", *r->word.gl_pathv);
+ globfree(&r->word);
+ } else {
+ final_printf("&%d\n", r->dup);
+ }
+ rnext=r->next;
+ free(r);
+ }
+ child->redirects=NULL;
+ }
+ free(pi->progs); /* children are an array, they get freed all at once */
+ pi->progs=NULL;
+ return ret_code;
+}
+
+static int run_list_test(struct pipe *head, int indent)
+{
+ int rcode=0; /* if list has no members */
+ struct pipe *pi, *next;
+ char *ind = indenter(indent);
+ for (pi=head; pi; pi=next) {
+ if (pi->num_progs == 0) break;
+ final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode);
+ rcode = run_pipe_test(pi, indent);
+ final_printf("%s pipe followup code %d\n", ind, pi->followup);
+ next=pi->next;
+ pi->next=NULL;
+ free(pi);
+ }
+ return rcode;
+}
+
+/* Select which version we will use */
+static int run_list(struct pipe *pi)
+{
+ int rcode=0;
+ if (fake_mode==0) {
+ rcode = run_list_real(pi);
+ }
+ /* run_list_test has the side effect of clearing memory
+ * In the long run that function can be merged with run_list_real,
+ * but doing that now would hobble the debugging effort. */
+ run_list_test(pi,0);
+ return rcode;
+}
+
+/* The API for glob is arguably broken. This routine pushes a non-matching
+ * string into the output structure, removing non-backslashed backslashes.
+ * If someone can prove me wrong, by performing this function within the
+ * original glob(3) api, feel free to rewrite this routine into oblivion.
+ * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
+ * XXX broken if the last character is '\\', check that before calling.
+ */
+static int globhack(const char *src, int flags, glob_t *pglob)
+{
+ int cnt, pathc;
+ const char *s;
+ char *dest;
+ for (cnt=1, s=src; *s; s++) {
+ if (*s == '\\') s++;
+ cnt++;
+ }
+ dest = malloc(cnt);
+ if (!dest) return GLOB_NOSPACE;
+ if (!(flags & GLOB_APPEND)) {
+ pglob->gl_pathv=NULL;
+ pglob->gl_pathc=0;
+ pglob->gl_offs=0;
+ pglob->gl_offs=0;
+ }
+ pathc = ++pglob->gl_pathc;
+ pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
+ if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
+ pglob->gl_pathv[pathc-1]=dest;
+ pglob->gl_pathv[pathc]=NULL;
+ for (s=src; *s; s++, dest++) {
+ if (*s == '\\') s++;
+ *dest = *s;
+ }
+ *dest='\0';
+ return 0;
+}
+
+/* XXX broken if the last character is '\\', check that before calling */
+static int glob_needed(const char *s)
+{
+ for (; *s; s++) {
+ if (*s == '\\') s++;
+ if (strchr("*[?",*s)) return 1;
+ }
+ return 0;
+}
+
+#if 0
+static void globprint(glob_t *pglob)
+{
+ int i;
+ debug_printf("glob_t at %p:\n", pglob);
+ debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n",
+ pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags);
+ for (i=0; i<pglob->gl_pathc; i++)
+ debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i,
+ pglob->gl_pathv[i], pglob->gl_pathv[i]);
+}
+#endif
+
+static int xglob(o_string *dest, int flags, glob_t *pglob)
+{
+ int gr;
+
+ /* short-circuit for null word */
+ /* we can code this better when the debug_printf's are gone */
+ if (dest->length == 0) {
+ if (dest->nonnull) {
+ /* bash man page calls this an "explicit" null */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ } else {
+ return 0;
+ }
+ } else if (glob_needed(dest->data)) {
+ gr = glob(dest->data, flags, NULL, pglob);
+ debug_printf("glob returned %d\n",gr);
+ if (gr == GLOB_NOMATCH) {
+ /* quote removal, or more accurately, backslash removal */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ }
+ } else {
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n",gr);
+ }
+ if (gr == GLOB_NOSPACE) {
+ fprintf(stderr,"out of memory during glob\n");
+ exit(1);
+ }
+ if (gr != 0) { /* GLOB_ABORTED ? */
+ fprintf(stderr,"glob(3) error %d\n",gr);
+ }
+ /* globprint(glob_target); */
+ return gr;
+}
+
+/* the src parameter allows us to peek forward to a possible &n syntax
+ * for file descriptor duplication, e.g., "2>&1".
+ * Return code is 0 normally, 1 if a syntax error is detected in src.
+ * Resource errors (in xmalloc) cause the process to exit */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
+ struct in_str *input)
+{
+ struct child_prog *child=ctx->child;
+ struct redir_struct *redir = child->redirects;
+ struct redir_struct *last_redir=NULL;
+
+ /* Create a new redir_struct and drop it onto the end of the linked list */
+ while(redir) {
+ last_redir=redir;
+ redir=redir->next;
+ }
+ redir = xmalloc(sizeof(struct redir_struct));
+ redir->next=NULL;
+ if (last_redir) {
+ last_redir->next=redir;
+ } else {
+ child->redirects=redir;
+ }
+
+ redir->type=style;
+ redir->fd= (fd==-1) ? redir_table[style].default_fd : fd ;
+
+ debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
+
+ /* Check for a '2>&1' type redirect */
+ redir->dup = redirect_dup_num(input);
+ if (redir->dup == -2) return 1; /* syntax error */
+ if (redir->dup != -1) {
+ /* Erik had a check here that the file descriptor in question
+ * is legit; I postpone that to "run time" */
+ debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
+ } else {
+ /* We do _not_ try to open the file that src points to,
+ * since we need to return and let src be expanded first.
+ * Set ctx->pending_redirect, so we know what to do at the
+ * end of the next parsed word.
+ */
+ ctx->pending_redirect = redir;
+ }
+ return 0;
+}
+
+struct pipe *new_pipe(void) {
+ struct pipe *pi;
+ pi = xmalloc(sizeof(struct pipe));
+ pi->num_progs = 0;
+ pi->progs = NULL;
+ pi->next = NULL;
+ pi->followup = 0; /* invalid */
+ return pi;
+}
+
+static void initialize_context(struct p_context *ctx)
+{
+ ctx->pipe=NULL;
+ ctx->pending_redirect=NULL;
+ ctx->child=NULL;
+ ctx->list_head=new_pipe();
+ ctx->pipe=ctx->list_head;
+ ctx->w=RES_NONE;
+ ctx->stack=NULL;
+ done_command(ctx); /* creates the memory for working child */
+}
+
+/* normal return is 0
+ * if a reserved word is found, and processed, return 1
+ * should handle if, then, elif, else, fi, for, while, until, do, done.
+ * case, function, and select are obnoxious, save those for later.
+ */
+int reserved_word(o_string *dest, struct p_context *ctx)
+{
+ struct reserved_combo {
+ char *literal;
+ int code;
+ long flag;
+ };
+ /* Mostly a list of accepted follow-up reserved words.
+ * FLAG_END means we are done with the sequence, and are ready
+ * to turn the compound list into a command.
+ * FLAG_START means the word must start a new compound list.
+ */
+ static struct reserved_combo reserved_list[] = {
+ { "if", RES_IF, FLAG_THEN | FLAG_START },
+ { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
+ { "elif", RES_ELIF, FLAG_THEN },
+ { "else", RES_ELSE, FLAG_FI },
+ { "fi", RES_FI, FLAG_END },
+ { "for", RES_FOR, FLAG_DO | FLAG_START },
+ { "while", RES_WHILE, FLAG_DO | FLAG_START },
+ { "until", RES_UNTIL, FLAG_DO | FLAG_START },
+ { "do", RES_DO, FLAG_DONE },
+ { "done", RES_DONE, FLAG_END }
+ };
+ struct reserved_combo *r;
+ for (r=reserved_list;
+#define NRES sizeof(reserved_list)/sizeof(struct reserved_combo)
+ r<reserved_list+NRES; r++) {
+ if (strcmp(dest->data, r->literal) == 0) {
+ debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
+ if (r->flag & FLAG_START) {
+ struct p_context *new = xmalloc(sizeof(struct p_context));
+ debug_printf("push stack\n");
+ *new = *ctx; /* physical copy */
+ initialize_context(ctx);
+ ctx->stack=new;
+ } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) {
+ syntax(); /* XXX how do we get out? */
+ }
+ ctx->w=r->code;
+ ctx->old_flag = r->flag;
+ if (ctx->old_flag & FLAG_END) {
+ struct p_context *old;
+ debug_printf("pop stack\n");
+ old = ctx->stack;
+ old->child->group = ctx->list_head;
+ *ctx = *old; /* physical copy */
+ free(old);
+ ctx->w=RES_NONE;
+ }
+ b_reset (dest);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/* normal return is 0.
+ * Syntax or xglob errors return 1. */
+static int done_word(o_string *dest, struct p_context *ctx)
+{
+ struct child_prog *child=ctx->child;
+ glob_t *glob_target;
+ int gr, flags = 0;
+
+ debug_printf("done_word: %s %p\n", dest->data, child);
+ if (dest->length == 0 && !dest->nonnull) {
+ debug_printf(" true null, ignored\n");
+ return 0;
+ }
+ if (ctx->pending_redirect) {
+ glob_target = &ctx->pending_redirect->word;
+ } else {
+ if (child->group) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ if (!child->argv) {
+ debug_printf("checking %s for reserved-ness\n",dest->data);
+ if (reserved_word(dest,ctx)) return 0;
+ }
+ glob_target = &child->glob_result;
+ if (child->argv) flags |= GLOB_APPEND;
+ }
+ gr = xglob(dest, flags, glob_target);
+ if (gr != 0) return 1;
+
+ b_reset(dest);
+ if (ctx->pending_redirect) {
+ ctx->pending_redirect=NULL;
+ if (glob_target->gl_pathc != 1) {
+ fprintf(stderr, "ambiguous redirect\n");
+ return 1;
+ }
+ } else {
+ child->argv = glob_target->gl_pathv;
+ }
+ return 0;
+}
+
+/* The only possible error here is out of memory, in which case
+ * xmalloc exits. */
+static int done_command(struct p_context *ctx)
+{
+ /* The child is really already in the pipe structure, so
+ * advance the pipe counter and make a new, null child.
+ * Only real trickiness here is that the uncommitted
+ * child structure, to which ctx->child points, is not
+ * counted in pi->num_progs. */
+ struct pipe *pi=ctx->pipe;
+ struct child_prog *prog=ctx->child;
+
+ if (prog && prog->group == NULL
+ && prog->argv == NULL
+ && prog->redirects == NULL) {
+ debug_printf("done_command: skipping null command\n");
+ return 0;
+ } else if (prog) {
+ pi->num_progs++;
+ debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
+ } else {
+ debug_printf("done_command: initializing\n");
+ }
+ pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
+
+ prog = pi->progs + pi->num_progs;
+ prog->redirects = NULL;
+ prog->argv = NULL;
+ prog->is_stopped = 0;
+ prog->group = NULL;
+ prog->glob_result.gl_pathv = NULL;
+ prog->family = pi;
+
+ ctx->child=prog;
+ /* but ctx->pipe and ctx->list_head remain unchanged */
+ return 0;
+}
+
+static int done_pipe(struct p_context *ctx, pipe_style type)
+{
+ struct pipe *new_p;
+ done_command(ctx); /* implicit closure of previous command */
+ debug_printf("done_pipe, type %d\n", type);
+ ctx->pipe->followup = type;
+ ctx->pipe->r_mode = ctx->w;
+ new_p=new_pipe();
+ ctx->pipe->next = new_p;
+ ctx->pipe = new_p;
+ ctx->child = NULL;
+ done_command(ctx); /* set up new pipe to accept commands */
+ return 0;
+}
+
+/* peek ahead in the in_str to find out if we have a "&n" construct,
+ * as in "2>&1", that represents duplicating a file descriptor.
+ * returns either -2 (syntax error), -1 (no &), or the number found.
+ */
+static int redirect_dup_num(struct in_str *input)
+{
+ int ch, d=0, ok=0;
+ ch = b_peek(input);
+ if (ch != '&') return -1;
+
+ b_getch(input); /* get the & */
+ while (ch=b_peek(input),isdigit(ch)) {
+ d = d*10+(ch-'0');
+ ok=1;
+ b_getch(input);
+ }
+ if (ok) return d;
+
+ fprintf(stderr, "ambiguous redirect\n");
+ return -2;
+}
+
+/* If a redirect is immediately preceded by a number, that number is
+ * supposed to tell which file descriptor to redirect. This routine
+ * looks for such preceding numbers. In an ideal world this routine
+ * needs to handle all the following classes of redirects...
+ * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
+ * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
+ * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
+ * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
+ * A -1 output from this program means no valid number was found, so the
+ * caller should use the appropriate default for this redirection.
+ */
+static int redirect_opt_num(o_string *o)
+{
+ int num;
+
+ if (o->length==0) return -1;
+ for(num=0; num<o->length; num++) {
+ if (!isdigit(*(o->data+num))) {
+ return -1;
+ }
+ }
+ /* reuse num (and save an int) */
+ num=atoi(o->data);
+ b_reset(o);
+ return num;
+}
+
+FILE *generate_stream_from_list(struct pipe *head)
+{
+ FILE *pf;
+#if 1
+ int pid, channel[2];
+ if (pipe(channel)<0) perror_msg_and_die("pipe");
+ pid=fork();
+ if (pid<0) {
+ perror_msg_and_die("fork");
+ } else if (pid==0) {
+ close(channel[0]);
+ if (channel[1] != 1) {
+ dup2(channel[1],1);
+ close(channel[1]);
+ }
+#if 0
+#define SURROGATE "surrogate response"
+ write(1,SURROGATE,sizeof(SURROGATE));
+ exit(run_list(head));
+#else
+ exit(run_list_real(head)); /* leaks memory */
+#endif
+ }
+ debug_printf("forked child %d\n",pid);
+ close(channel[1]);
+ pf = fdopen(channel[0],"r");
+ debug_printf("pipe on FILE *%p\n",pf);
+#else
+ run_list_test(head,0);
+ pf=popen("echo surrogate response","r");
+ debug_printf("started fake pipe on FILE *%p\n",pf);
+#endif
+ return pf;
+}
+
+/* this version hacked for testing purposes */
+/* return code is exit status of the process that is run. */
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
+{
+ int retcode;
+ o_string result=NULL_O_STRING;
+ struct p_context inner;
+ FILE *p;
+ struct in_str pipe_str;
+ initialize_context(&inner);
+
+ /* recursion to generate command */
+ retcode = parse_stream(&result, &inner, input, subst_end);
+ if (retcode != 0) return retcode; /* syntax error or EOF */
+ done_word(&result, &inner);
+ done_pipe(&inner, PIPE_SEQ);
+ b_free(&result);
+
+ p=generate_stream_from_list(inner.list_head);
+ if (p==NULL) return 1;
+ mark_open(fileno(p));
+ setup_file_in_str(&pipe_str, p);
+
+ /* now send results of command back into original context */
+ retcode = parse_stream(dest, ctx, &pipe_str, '\0');
+ /* XXX In case of a syntax error, should we try to kill the child?
+ * That would be tough to do right, so just read until EOF. */
+ if (retcode == 1) {
+ while (b_getch(&pipe_str)!=EOF) { /* discard */ };
+ }
+
+ debug_printf("done reading from pipe, pclose()ing\n");
+ /* This is the step that wait()s for the child. Should be pretty
+ * safe, since we just read an EOF from its stdout. We could try
+ * to better, by using wait(), and keeping track of background jobs
+ * at the same time. That would be a lot of work, and contrary
+ * to the KISS philosophy of this program. */
+ mark_closed(fileno(p));
+ retcode=pclose(p);
+ debug_printf("pclosed, retcode=%d\n",retcode);
+ /* XXX this process fails to trim a single trailing newline */
+ return retcode;
+}
+
+static int parse_group(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int ch)
+{
+ int rcode, endch=0;
+ struct p_context sub;
+ struct child_prog *child = ctx->child;
+ if (child->argv) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ initialize_context(&sub);
+ switch(ch) {
+ case '(': endch=')'; child->subshell=1; break;
+ case '{': endch='}'; break;
+ default: syntax(); /* really logic error */
+ }
+ rcode=parse_stream(dest,&sub,input,endch);
+ done_word(dest,&sub); /* finish off the final word in the subcontext */
+ done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
+ child->group = sub.list_head;
+ return rcode;
+ /* child remains "open", available for possible redirects */
+}
+
+/* basically useful version until someone wants to get fancier,
+ * see the bash man page under "Parameter Expansion" */
+static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src)
+{
+ const char *p=NULL;
+ if (src->data) p = getenv(src->data);
+ if (p) parse_string(dest, ctx, p); /* recursion */
+ b_free(src);
+}
+
+/* return code: 0 for OK, 1 for syntax error */
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
+{
+ int i, advance=0;
+ o_string alt=NULL_O_STRING;
+ char sep[]=" ";
+ int ch = input->peek(input); /* first character after the $ */
+ debug_printf("handle_dollar: ch=%c\n",ch);
+ if (isalpha(ch)) {
+ while(ch=b_peek(input),isalnum(ch) || ch=='_') {
+ b_getch(input);
+ b_addchr(&alt,ch);
+ }
+ lookup_param(dest, ctx, &alt);
+ } else if (isdigit(ch)) {
+ i = ch-'0'; /* XXX is $0 special? */
+ if (i<global_argc) {
+ parse_string(dest, ctx, global_argv[i]); /* recursion */
+ }
+ advance = 1;
+ } else switch (ch) {
+ case '$':
+ b_adduint(dest,getpid());
+ advance = 1;
+ break;
+ case '!':
+ if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
+ advance = 1;
+ break;
+ case '?':
+ b_adduint(dest,last_return_code);
+ advance = 1;
+ break;
+ case '#':
+ b_adduint(dest,global_argc ? global_argc-1 : 0);
+ advance = 1;
+ break;
+ case '{':
+ b_getch(input);
+ /* XXX maybe someone will try to escape the '}' */
+ while(ch=b_getch(input),ch!=EOF && ch!='}') {
+ b_addchr(&alt,ch);
+ }
+ if (ch != '}') {
+ syntax();
+ return 1;
+ }
+ lookup_param(dest, ctx, &alt);
+ break;
+ case '(':
+ process_command_subs(dest, ctx, input, ')');
+ break;
+ case '*':
+ sep[0]=ifs[0];
+ for (i=1; i<global_argc; i++) {
+ parse_string(dest, ctx, global_argv[i]);
+ if (i+1 < global_argc) parse_string(dest, ctx, sep);
+ }
+ break;
+ case '@':
+ case '-':
+ case '_':
+ /* still unhandled, but should be eventually */
+ fprintf(stderr,"unhandled syntax: $%c\n",ch);
+ return 1;
+ break;
+ default:
+ b_addqchr(dest,'$',dest->quote);
+ }
+ /* Eat the character if the flag was set. If the compiler
+ * is smart enough, we could substitute "b_getch(input);"
+ * for all the "advance = 1;" above, and also end up with
+ * a nice size-optimized program. Hah! That'll be the day.
+ */
+ if (advance) b_getch(input);
+ return 0;
+}
+
+int parse_string(o_string *dest, struct p_context *ctx, const char *src)
+{
+ struct in_str foo;
+ setup_string_in_str(&foo, src);
+ return parse_stream(dest, ctx, &foo, '\0');
+}
+
+/* return code is 0 for normal exit, 1 for syntax error */
+int parse_stream(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int end_trigger)
+{
+ unsigned int ch, m;
+ int redir_fd;
+ redir_type redir_style;
+ int next;
+
+ /* Only double-quote state is handled in the state variable dest->quote.
+ * A single-quote triggers a bypass of the main loop until its mate is
+ * found. When recursing, quote state is passed in via dest->quote. */
+
+ debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
+ while ((ch=b_getch(input))!=EOF) {
+ m = map[ch];
+ next = (ch == '\n') ? 0 : b_peek(input);
+ debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
+ ch,ch,m,dest->quote);
+ if (m==0 || ((m==1 || m==2) && dest->quote)) {
+ b_addqchr(dest, ch, dest->quote);
+ } else if (ch == end_trigger && !dest->quote) {
+ debug_printf("leaving parse_stream\n");
+ return 0;
+ } else if (m==2 && !dest->quote) { /* IFS */
+ done_word(dest, ctx);
+#if 0
+ if (ch=='\n') {
+ /* Yahoo! Time to run with it! */
+ done_pipe(ctx,PIPE_SEQ);
+ run_list(ctx->list_head);
+ initialize_context(ctx);
+ }
+#endif
+ } else switch (ch) {
+ case '#':
+ if (dest->length == 0 && !dest->quote) {
+ while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); }
+ } else {
+ b_addqchr(dest, ch, dest->quote);
+ }
+ break;
+ case '\\':
+ if (next == EOF) {
+ syntax();
+ return 1;
+ }
+ b_addqchr(dest, '\\', dest->quote);
+ b_addqchr(dest, b_getch(input), dest->quote);
+ break;
+ case '$':
+ if (handle_dollar(dest, ctx, input)!=0) return 1;
+ break;
+ case '\'':
+ dest->nonnull = 1;
+ while(ch=b_getch(input),ch!=EOF && ch!='\'') {
+ b_addchr(dest,ch);
+ }
+ if (ch==EOF) {
+ syntax();
+ return 1;
+ }
+ break;
+ case '"':
+ dest->nonnull = 1;
+ dest->quote = !dest->quote;
+ break;
+ case '`':
+ process_command_subs(dest, ctx, input, '`');
+ break;
+ case '>':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style=REDIRECT_OVERWRITE;
+ if (next == '>') {
+ redir_style=REDIRECT_APPEND;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support >(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case '<':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style=REDIRECT_INPUT;
+ if (next == '<') {
+ redir_style=REDIRECT_HEREIS;
+ b_getch(input);
+ } else if (next == '>') {
+ redir_style=REDIRECT_IO;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support <(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case ';':
+ done_word(dest, ctx);
+ done_pipe(ctx,PIPE_SEQ);
+ break;
+ case '&':
+ done_word(dest, ctx);
+ if (next=='&') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_AND);
+ } else {
+ done_pipe(ctx,PIPE_BG);
+ }
+ break;
+ case '|':
+ done_word(dest, ctx);
+ if (next=='|') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_OR);
+ } else {
+ /* we could pick up a file descriptor choice here
+ * with redirect_opt_num(), but bash doesn't do it.
+ * "echo foo 2| cat" yields "foo 2". */
+ done_command(ctx);
+ }
+ break;
+ case '(':
+ case '{':
+ if (parse_group(dest, ctx, input, ch)!=0) return 1;
+ break;
+ case ')':
+ case '}':
+ syntax(); /* Proper use of this character caught by end_trigger */
+ return 1;
+ break;
+ default:
+ syntax(); /* this is really an internal logic error */
+ return 1;
+ }
+ }
+ /* complain if quote? No, maybe we just finished a command substitution
+ * that was quoted. Example:
+ * $ echo "`cat foo` plus more"
+ * and we just got the EOF generated by the subshell that ran "cat foo"
+ * The only real complaint is if we got an EOF when end_trigger != '\0',
+ * that is, we were really supposed to get end_trigger, and never got
+ * one before the EOF. Can't use the standard "syntax error" return code,
+ * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
+ if (end_trigger != '\0') return -1;
+ return 0;
+}
+
+void mapset(const unsigned char *set, int code)
+{
+ const unsigned char *s;
+ for (s=set; *s; s++) map[*s] = code;
+}
+
+void update_ifs_map(void)
+{
+ /* char *ifs and char map[256] are both globals. */
+ ifs = getenv("IFS");
+ if (ifs == NULL) ifs=" \t\n";
+ /* Precompute a list of 'flow through' behavior so it can be treated
+ * quickly up front. Computation is necessary because of IFS.
+ * Special case handling of IFS == " \t\n" is not implemented.
+ * The map[] array only really needs two bits each, and on most machines
+ * that would be faster because of the reduced L1 cache footprint.
+ */
+ memset(map,0,256); /* most characters flow through always */
+ mapset("\\$'\"`", 3); /* never flow through */
+ mapset("<>;&|(){}#", 1); /* flow through if quoted */
+ mapset(ifs, 2); /* also flow through if quoted */
+}
+
+/* most recursion does not come through here, the exeception is
+ * from builtin_source() */
+int parse_stream_outer(struct in_str *inp)
+{
+
+ struct p_context ctx;
+ o_string temp=NULL_O_STRING;
+ int rcode;
+ do {
+ initialize_context(&ctx);
+ update_ifs_map();
+ inp->promptmode=1;
+ rcode = parse_stream(&temp, &ctx, inp, '\n');
+ done_word(&temp, &ctx);
+ done_pipe(&ctx,PIPE_SEQ);
+ run_list(ctx.list_head);
+ } while (rcode != -1); /* loop on syntax errors, return on EOF */
+ return 0;
+}
+
+static int parse_string_outer(const char *s)
+{
+ struct in_str input;
+ setup_string_in_str(&input, s);
+ return parse_stream_outer(&input);
+}
+
+static int parse_file_outer(FILE *f)
+{
+ int rcode;
+ struct in_str input;
+ setup_file_in_str(&input, f);
+ rcode = parse_stream_outer(&input);
+ return rcode;
+}
+
+int shell_main(int argc, char **argv)
+{
+ int opt;
+ FILE *input;
+
+ /* XXX what should these be while sourcing /etc/profile? */
+ global_argc = argc;
+ global_argv = argv;
+
+ if (argv[0] && argv[0][0] == '-') {
+ debug_printf("\nsourcing /etc/profile\n");
+ input = xfopen("/etc/profile", "r");
+ mark_open(fileno(input));
+ parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ }
+ input=stdin;
+
+ /* initialize the cwd -- this is never freed...*/
+ cwd = xgetcwd(0);
+#ifdef BB_FEATURE_COMMAND_EDITING
+ cmdedit_set_initial_prompt();
+#else
+ PS1 = NULL;
+#endif
+
+ while ((opt = getopt(argc, argv, "c:xif")) > 0) {
+ switch (opt) {
+ case 'c':
+ {
+ global_argv = argv+optind;
+ global_argc = argc-optind;
+ opt = parse_string_outer(optarg);
+ exit(opt);
+ }
+ break;
+ case 'i':
+ interactive++;
+ break;
+ case 'f':
+ fake_mode++;
+ break;
+ default:
+ fprintf(stderr, "Usage: sh [FILE]...\n"
+ " or: sh -c command [args]...\n\n");
+ exit(EXIT_FAILURE);
+ }
+ }
+ /* A shell is interactive if the `-i' flag was given, or if all of
+ * the following conditions are met:
+ * no -c command
+ * no arguments remaining or the -s flag given
+ * standard input is a terminal
+ * standard output is a terminal
+ * Refer to Posix.2, the description of the `sh' utility. */
+ if (argv[optind]==NULL && input==stdin &&
+ isatty(fileno(stdin)) && isatty(fileno(stdout))) {
+ interactive++;
+ }
+
+ if (interactive) {
+ /* Looks like they want an interactive shell */
+ fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n");
+ exit(parse_file_outer(stdin));
+ }
+ debug_printf("\ninteractive=%d\n", interactive);
+
+ debug_printf("\nrunning script '%s'\n", argv[optind]);
+ global_argv = argv+optind;
+ global_argc = argc-optind;
+ input = xfopen(argv[optind], "r");
+ opt = parse_file_outer(input);
+
+#ifdef BB_FEATURE_CLEAN_UP
+ fclose(input.file);
+#endif
+
+ return(opt);
+}