diff options
Diffstat (limited to 'shell/hush.c')
| -rw-r--r-- | shell/hush.c | 149 |
1 files changed, 91 insertions, 58 deletions
diff --git a/shell/hush.c b/shell/hush.c index d5955dd..7cf2f33 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -54,7 +54,7 @@ * port selected bugfixes from post-0.49 busybox lash - done? * change { and } from special chars to reserved words * builtins: return, trap, ulimit - * test magic exec + * test magic exec with redirection only * check setting of global_argc and global_argv * follow IFS rules more precisely, including update semantics * figure out what to do with backslash-newline @@ -73,7 +73,7 @@ #include <fnmatch.h> #endif -#define HUSH_VER_STR "0.9" +#define HUSH_VER_STR "0.91" #if !BB_MMU && ENABLE_HUSH_TICK //#undef ENABLE_HUSH_TICK @@ -525,13 +525,13 @@ static int free_pipe(struct pipe *pi, int indent); static int setup_redirects(struct command *prog, int squirrel[]); static int run_list(struct pipe *pi); #if BB_MMU -#define pseudo_exec_argv(ptrs2free, argv, assignment_cnt, argv_expanded) \ +#define pseudo_exec_argv(ptr_ptrs2free, argv, assignment_cnt, argv_expanded) \ pseudo_exec_argv(argv, assignment_cnt, argv_expanded) -#define pseudo_exec(ptrs2free, command, argv_expanded) \ +#define pseudo_exec(ptr_ptrs2free, command, argv_expanded) \ pseudo_exec(command, argv_expanded) #endif -static void pseudo_exec_argv(char **ptrs2free, char **argv, int assignment_cnt, char **argv_expanded) NORETURN; -static void pseudo_exec(char **ptrs2free, struct command *command, char **argv_expanded) NORETURN; +static void pseudo_exec_argv(char ***ptr_ptrs2free, char **argv, int assignment_cnt, char **argv_expanded) NORETURN; +static void pseudo_exec(char ***ptr_ptrs2free, struct command *command, char **argv_expanded) NORETURN; static int run_pipe(struct pipe *pi); /* data structure manipulation: */ static int setup_redirect(struct parse_context *ctx, int fd, redir_type style, struct in_str *input); @@ -576,6 +576,9 @@ static int set_local_var(char *str, int flg_export); static void unset_local_var(const char *name); +static const char hush_version_str[] ALIGN1 = "HUSH_VERSION="HUSH_VER_STR; + + static int glob_needed(const char *s) { while (*s) { @@ -650,26 +653,44 @@ static char **add_malloced_string_to_strings(char **strings, char *add) return add_malloced_strings_to_strings(strings, v); } -static void free_strings(char **strings) +static void free_strings_and_unsetenv(char **strings, int unset) { - if (strings) { - char **v = strings; - while (*v) - free(*v++); - free(strings); + char **v; + + if (!strings) + return; + + v = strings; + while (*v) { + if (unset) { + char *copy; +#if !BB_MMU + /* If this is a magic guard pointer, do not free it, + * and stop unsetting */ + if (*v == hush_version_str) { + unset = 0; + v++; + continue; + } +#endif + /* *strchrnul(*v, '=') = '\0'; -- BAD + * In case *v was putenv'ed, we can't + * unsetenv(*v) after taking out '=': + * it won't work, env is modified by taking out! + * horror :( */ + copy = xstrndup(*v, strchrnul(*v, '=') - *v); + unsetenv(copy); + free(copy); + } + free(*v++); } + free(strings); } -#if !BB_MMU -#define EXTRA_PTRS 5 /* 1 for NULL, 1 for args, 3 for paranoid reasons */ -static char **alloc_ptrs(char **argv) +static void free_strings(char **strings) { - char **v = argv; - while (*v) - v++; - return xzalloc((v - argv + EXTRA_PTRS) * sizeof(v[0])); + free_strings_and_unsetenv(strings, 0); } -#endif /* Function prototypes for builtins */ @@ -1393,34 +1414,36 @@ static void restore_redirects(int squirrel[]) * XXX no exit() here. If you don't exec, use _exit instead. * The at_exit handlers apparently confuse the calling process, * in particular stdin handling. Not sure why? -- because of vfork! (vda) */ -static void pseudo_exec_argv(char **ptrs2free, char **argv, int assignment_cnt, char **argv_expanded) +static void pseudo_exec_argv(char ***ptr_ptrs2free, char **argv, int assignment_cnt, char **argv_expanded) { int i, rcode; char *p; const struct built_in_command *x; - for (i = 0; i < assignment_cnt; i++) { - debug_printf_exec("pid %d environment modification: %s\n", - getpid(), argv[i]); - p = expand_string_to_string(argv[i]); -#if !BB_MMU - *ptrs2free++ = p; -#endif - putenv(p); - } - argv += i; /* If a variable is assigned in a forest, and nobody listens, * was it ever really set? */ - if (!argv[0]) + if (!argv[assignment_cnt]) _exit(EXIT_SUCCESS); + for (i = 0; i < assignment_cnt; i++) { + debug_printf_exec("pid %d environment modification: %s\n", + getpid(), *argv); + p = expand_string_to_string(*argv); + putenv(p); +#if !BB_MMU + *ptr_ptrs2free = add_malloced_string_to_strings(*ptr_ptrs2free, p); +#endif + argv++; + } if (argv_expanded) { argv = argv_expanded; } else { argv = expand_strvec_to_strvec(argv); #if !BB_MMU - *ptrs2free++ = (char*) argv; + /* Inserting magic guard pointer to not unsetenv junk later */ + *ptr_ptrs2free = add_malloced_string_to_strings(*ptr_ptrs2free, (char*)hush_version_str); + *ptr_ptrs2free = add_malloced_string_to_strings(*ptr_ptrs2free, (char*)argv); #endif } @@ -1466,10 +1489,10 @@ static void pseudo_exec_argv(char **ptrs2free, char **argv, int assignment_cnt, /* Called after [v]fork() in run_pipe() */ -static void pseudo_exec(char **ptrs2free, struct command *command, char **argv_expanded) +static void pseudo_exec(char ***ptr_ptrs2free, struct command *command, char **argv_expanded) { if (command->argv) - pseudo_exec_argv(ptrs2free, command->argv, command->assignment_cnt, argv_expanded); + pseudo_exec_argv(ptr_ptrs2free, command->argv, command->assignment_cnt, argv_expanded); if (command->group) { #if !BB_MMU @@ -1745,6 +1768,7 @@ static int run_pipe(struct pipe *pi) int nextin; int pipefds[2]; /* pipefds[0] is for reading */ struct command *command; + char **ptrs2free = NULL; char **argv_expanded = NULL; char **argv; const struct built_in_command *x; @@ -1796,7 +1820,7 @@ static int run_pipe(struct pipe *pi) for (i = 0; i < command->assignment_cnt; i++) { p = expand_string_to_string(argv[i]); putenv(p); -//FIXME: do we leak p?! + ptrs2free = add_malloced_string_to_strings(ptrs2free, p); } /* Expand the rest into (possibly) many strings each */ @@ -1805,9 +1829,10 @@ static int run_pipe(struct pipe *pi) for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) { if (strcmp(argv_expanded[0], x->cmd) == 0) { if (x->function == builtin_exec && argv_expanded[1] == NULL) { - debug_printf("magic exec\n"); + debug_printf("exec with redirects only\n"); setup_redirects(command, NULL); - return EXIT_SUCCESS; + rcode = EXIT_SUCCESS; + goto clean_up_and_ret1; } debug_printf("builtin inline %s\n", argv_expanded[0]); /* XXX setup_redirects acts on file descriptors, not FILEs. @@ -1817,10 +1842,13 @@ static int run_pipe(struct pipe *pi) setup_redirects(command, squirrel); debug_printf_exec(": builtin '%s' '%s'...\n", x->cmd, argv_expanded[1]); rcode = x->function(argv_expanded) & 0xff; - free(argv_expanded); + USE_FEATURE_SH_STANDALONE(clean_up_and_ret:) restore_redirects(squirrel); - debug_printf_exec("run_pipe return %d\n", rcode); + clean_up_and_ret1: + free_strings_and_unsetenv(ptrs2free, 1); + free(argv_expanded); IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) + debug_printf_exec("run_pipe return %d\n", rcode); return rcode; } } @@ -1832,11 +1860,7 @@ static int run_pipe(struct pipe *pi) save_nofork_data(&G.nofork_save); debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]); rcode = run_nofork_applet_prime(&G.nofork_save, a, argv_expanded); - free(argv_expanded); - restore_redirects(squirrel); - debug_printf_exec("run_pipe return %d\n", rcode); - IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) - return rcode; + goto clean_up_and_ret; } } #endif @@ -1856,14 +1880,15 @@ static int run_pipe(struct pipe *pi) for (i = 0; i < pi->num_cmds; i++) { #if !BB_MMU - char **ptrs2free = NULL; + /* Avoid confusion WHAT is volatile. Pointer is volatile, + * not the stuff it points to. */ + typedef char **ppchar_t; + volatile ppchar_t shared_across_vfork; #endif + command = &(pi->cmds[i]); if (command->argv) { debug_printf_exec(": pipe member '%s' '%s'...\n", command->argv[0], command->argv[1]); -#if !BB_MMU - ptrs2free = alloc_ptrs(command->argv); -#endif } else debug_printf_exec(": pipe member with no argv\n"); @@ -1873,6 +1898,9 @@ static int run_pipe(struct pipe *pi) if ((i + 1) < pi->num_cmds) xpipe(pipefds); +#if !BB_MMU + shared_across_vfork = ptrs2free; +#endif command->pid = BB_MMU ? fork() : vfork(); if (!command->pid) { /* child */ if (ENABLE_HUSH_JOB) @@ -1906,13 +1934,19 @@ static int run_pipe(struct pipe *pi) set_jobctrl_sighandler(SIG_DFL); set_misc_sighandler(SIG_DFL); signal(SIGCHLD, SIG_DFL); - pseudo_exec(ptrs2free, command, argv_expanded); /* does not return */ +/* comment how it sets env???? +for single_and_fg, it's already set yes? */ + pseudo_exec((char ***) &shared_across_vfork, command, argv_expanded); + /* pseudo_exec() does not return */ } - free(argv_expanded); - argv_expanded = NULL; + /* parent */ #if !BB_MMU - free_strings(ptrs2free); + ptrs2free = shared_across_vfork; #endif + free(argv_expanded); + argv_expanded = NULL; + free_strings_and_unsetenv(ptrs2free, 1); + ptrs2free = NULL; if (command->pid < 0) { /* [v]fork failed */ /* Clearly indicate, was it fork or vfork */ bb_perror_msg(BB_MMU ? "fork" : "vfork"); @@ -4077,10 +4111,9 @@ static void setup_job_control(void) int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int hush_main(int argc, char **argv) { - static const char version_str[] ALIGN1 = "HUSH_VERSION="HUSH_VER_STR; static const struct variable const_shell_ver = { .next = NULL, - .varstr = (char*)version_str, + .varstr = (char*)hush_version_str, .max_len = 1, /* 0 can provoke free(name) */ .flg_export = 1, .flg_read_only = 1, @@ -4114,7 +4147,7 @@ int hush_main(int argc, char **argv) } e++; } - putenv((char *)version_str); /* reinstate HUSH_VERSION */ + putenv((char *)hush_version_str); /* reinstate HUSH_VERSION */ #if ENABLE_FEATURE_EDITING G.line_input_state = new_line_input_t(FOR_SHELL); @@ -4338,10 +4371,10 @@ static int builtin_exec(char **argv) return EXIT_SUCCESS; /* bash does this */ { #if !BB_MMU - char **ptrs2free = alloc_ptrs(argv); + char **ptrs2free = NULL; #endif // FIXME: if exec fails, bash does NOT exit! We do... - pseudo_exec_argv(ptrs2free, argv + 1, 0, NULL); + pseudo_exec_argv(&ptrs2free, argv + 1, 0, NULL); /* never returns */ } } |