diff options
author | Eric Andersen | 2002-04-13 12:33:41 +0000 |
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committer | Eric Andersen | 2002-04-13 12:33:41 +0000 |
commit | 4c9b68f0e013b0b7554a3278e078177f955d39f4 (patch) | |
tree | e3caabb50e0a205221c61100ced2d0a545ff39ed /shell/hush.c | |
parent | a66a43e8ef1e55c2415aa7084365cce3fb8f931a (diff) | |
download | busybox-4c9b68f0e013b0b7554a3278e078177f955d39f4.zip busybox-4c9b68f0e013b0b7554a3278e078177f955d39f4.tar.gz |
Nice patch from Wolfgang Denk <wd@denx.de> to provide hush with
shell loops (for, while, until) and control operators (||, &&)
Diffstat (limited to 'shell/hush.c')
-rw-r--r-- | shell/hush.c | 347 |
1 files changed, 308 insertions, 39 deletions
diff --git a/shell/hush.c b/shell/hush.c index 27afd3e..08b3b29 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -116,6 +116,10 @@ #undef CONFIG_FEATURE_SH_FANCY_PROMPT #define BB_BANNER #endif +#define SPECIAL_VAR_SYMBOL 03 +#define FLAG_EXIT_FROM_LOOP 1 +#define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */ +#define FLAG_REPARSING (1 << 2) /* >=2nd pass */ typedef enum { REDIRECT_INPUT = 1, @@ -157,7 +161,8 @@ typedef enum { RES_DO = 9, RES_DONE = 10, RES_XXXX = 11, - RES_SNTX = 12 + RES_IN = 12, + RES_SNTX = 13 } reserved_style; #define FLAG_END (1<<RES_NONE) #define FLAG_IF (1<<RES_IF) @@ -170,6 +175,7 @@ typedef enum { #define FLAG_UNTIL (1<<RES_UNTIL) #define FLAG_DO (1<<RES_DO) #define FLAG_DONE (1<<RES_DONE) +#define FLAG_IN (1<<RES_IN) #define FLAG_START (1<<RES_XXXX) /* This holds pointers to the various results of parsing */ @@ -181,6 +187,7 @@ struct p_context { reserved_style w; int old_flag; /* for figuring out valid reserved words */ struct p_context *stack; + int type; /* define type of parser : ";$" common or special symbol */ /* How about quoting status? */ }; @@ -201,6 +208,8 @@ struct child_prog { 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 */ + int sp; /* number of SPECIAL_VAR_SYMBOL */ + int type; }; struct pipe { @@ -319,6 +328,7 @@ static void __syntax(char *file, int line) { /* function prototypes for builtins */ static int builtin_cd(struct child_prog *child); static int builtin_env(struct child_prog *child); +static int builtin_eval(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); @@ -376,19 +386,22 @@ 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 char *lookup_param(char *src); +static char *make_string(char **inp); 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_stream_outer(struct in_str *inp, int flag); +static int parse_string_outer(const char *s, int flag); static int parse_file_outer(FILE *f); /* job management: */ static int checkjobs(struct pipe* fg_pipe); static void insert_bg_job(struct pipe *pi); static void remove_bg_job(struct pipe *pi); /* local variable support */ +static char **make_list_in(char **inp, char *name); +static char *insert_var_value(char *inp); static char *get_local_var(const char *var); static void unset_local_var(const char *name); static int set_local_var(const char *s, int flg_export); @@ -405,7 +418,7 @@ static struct built_in_command bltins[] = { {"cd", "Change working directory", builtin_cd}, {"continue", "Continue for, while or until loop", builtin_not_written}, {"env", "Print all environment variables", builtin_env}, - {"eval", "Construct and run shell command", builtin_not_written}, + {"eval", "Construct and run shell command", builtin_eval}, {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, {"exit", "Exit from shell()", builtin_exit}, @@ -436,6 +449,21 @@ static const char *set_cwd(void) return cwd; } +/* built-in 'eval' handler */ +static int builtin_eval(struct child_prog *child) +{ + char *str = NULL; + int rcode = EXIT_SUCCESS; + + if (child->argv[1]) { + str = make_string(child->argv + 1); + parse_string_outer(str, FLAG_EXIT_FROM_LOOP | + FLAG_PARSE_SEMICOLON); + free(str); + rcode = last_return_code; + } + return rcode; +} /* built-in 'cd <path>' handler */ static int builtin_cd(struct child_prog *child) @@ -1046,11 +1074,14 @@ static void restore_redirects(int squirrel[]) static void pseudo_exec(struct child_prog *child) { int i, rcode; + char *p; struct built_in_command *x; if (child->argv) { for (i=0; is_assignment(child->argv[i]); i++) { debug_printf("pid %d environment modification: %s\n",getpid(),child->argv[i]); - putenv(strdup(child->argv[i])); + p = insert_var_value(child->argv[i]); + putenv(strdup(p)); + if (p != child->argv[i]) free(p); } child->argv+=i; /* XXX this hack isn't so horrible, since we are about to exit, and therefore don't need to keep data @@ -1317,6 +1348,7 @@ static int run_pipe_real(struct pipe *pi) int pipefds[2]; /* pipefds[0] is for reading */ struct child_prog *child; struct built_in_command *x; + char *p; nextin = 0; pi->pgrp = -1; @@ -1359,10 +1391,28 @@ static int run_pipe_real(struct pipe *pi) export_me=1; } free(name); - set_local_var(child->argv[i], export_me); + p = insert_var_value(child->argv[i]); + set_local_var(p, export_me); + if (p != child->argv[i]) free(p); } return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */ } + for (i = 0; is_assignment(child->argv[i]); i++) { + p = insert_var_value(child->argv[i]); + putenv(strdup(p)); + if (p != child->argv[i]) { + child->sp--; + free(p); + } + } + if (child->sp) { + char * str = NULL; + + str = make_string((child->argv + i)); + parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING); + free(str); + return last_return_code; + } for (x = bltins; x->cmd; x++) { if (strcmp(child->argv[i], x->cmd) == 0 ) { int squirrel[] = {-1, -1, -1}; @@ -1378,9 +1428,6 @@ static int run_pipe_real(struct pipe *pi) * Is it really safe for inline use? Experimentally, * things seem to work with glibc. */ setup_redirects(child, squirrel); - for (i=0; is_assignment(child->argv[i]); i++) { - putenv(strdup(child->argv[i])); - } child->argv+=i; /* XXX horrible hack */ rcode = x->function(child); child->argv-=i; /* XXX restore hack so free() can work right */ @@ -1474,19 +1521,97 @@ static int run_pipe_real(struct pipe *pi) static int run_list_real(struct pipe *pi) { - int rcode=0; + char *save_name = NULL; + char **list = NULL; + char **save_list = NULL; + struct pipe *rpipe; + int flag_rep = 0; + int save_num_progs; + int rcode=0, flag_skip=1; + int flag_restore = 0; int if_code=0, next_if_code=0; /* need double-buffer to handle elif */ reserved_style rmode, skip_more_in_this_rmode=RES_XXXX; - for (;pi;pi=pi->next) { + /* check syntax for "for" */ + for (rpipe = pi; rpipe; rpipe = rpipe->next) { + if ((rpipe->r_mode == RES_IN || + rpipe->r_mode == RES_FOR) && + (rpipe->next == NULL)) { + syntax(); + return 1; + } + if ((rpipe->r_mode == RES_IN && + (rpipe->next->r_mode == RES_IN && + rpipe->next->progs->argv != NULL))|| + (rpipe->r_mode == RES_FOR && + rpipe->next->r_mode != RES_IN)) { + syntax(); + return 1; + } + } + for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) { + if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL || + pi->r_mode == RES_FOR) { + flag_restore = 0; + if (!rpipe) { + flag_rep = 0; + rpipe = pi; + } + } rmode = pi->r_mode; debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode); - if (rmode == skip_more_in_this_rmode) continue; + if (rmode == skip_more_in_this_rmode && flag_skip) { + if (pi->followup == PIPE_SEQ) flag_skip=0; + continue; + } + flag_skip = 1; skip_more_in_this_rmode = RES_XXXX; 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 (rmode == RES_FOR && pi->num_progs) { + if (!list) { + /* if no variable values after "in" we skip "for" */ + if (!pi->next->progs->argv) continue; + /* create list of variable values */ + list = make_list_in(pi->next->progs->argv, + pi->progs->argv[0]); + save_list = list; + save_name = pi->progs->argv[0]; + pi->progs->argv[0] = NULL; + flag_rep = 1; + } + if (!(*list)) { + free(pi->progs->argv[0]); + free(save_list); + list = NULL; + flag_rep = 0; + pi->progs->argv[0] = save_name; + pi->progs->glob_result.gl_pathv[0] = + pi->progs->argv[0]; + continue; + } else { + /* insert new value from list for variable */ + if (pi->progs->argv[0]) + free(pi->progs->argv[0]); + pi->progs->argv[0] = *list++; + pi->progs->glob_result.gl_pathv[0] = + pi->progs->argv[0]; + } + } + if (rmode == RES_IN) continue; + if (rmode == RES_DO) { + if (!flag_rep) continue; + } + if ((rmode == RES_DONE)) { + if (flag_rep) { + flag_restore = 1; + } else { + rpipe = NULL; + } + } if (pi->num_progs == 0) continue; + save_num_progs = pi->num_progs; /* save number of programs */ rcode = run_pipe_real(pi); debug_printf("run_pipe_real returned %d\n",rcode); if (rcode!=-1) { @@ -1513,8 +1638,13 @@ static int run_list_real(struct pipe *pi) debug_printf("checkjobs returned %d\n",rcode); } last_return_code=rcode; + pi->num_progs = save_num_progs; /* restore number of programs */ if ( rmode == RES_IF || rmode == RES_ELIF ) next_if_code=rcode; /* can be overwritten a number of times */ + if (rmode == RES_WHILE) + flag_rep = !last_return_code; + if (rmode == RES_UNTIL) + flag_rep = last_return_code; if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) || (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) ) skip_more_in_this_rmode=rmode; @@ -1898,6 +2028,7 @@ static void initialize_context(struct p_context *ctx) ctx->pipe=ctx->list_head; ctx->w=RES_NONE; ctx->stack=NULL; + ctx->old_flag=0; done_command(ctx); /* creates the memory for working child */ } @@ -1924,9 +2055,10 @@ int reserved_word(o_string *dest, struct p_context *ctx) { "elif", RES_ELIF, FLAG_THEN }, { "else", RES_ELSE, FLAG_FI }, { "fi", RES_FI, FLAG_END }, - { "for", RES_FOR, FLAG_DO | FLAG_START }, + { "for", RES_FOR, FLAG_IN | FLAG_START }, { "while", RES_WHILE, FLAG_DO | FLAG_START }, { "until", RES_UNTIL, FLAG_DO | FLAG_START }, + { "in", RES_IN, FLAG_DO }, { "do", RES_DO, FLAG_DONE }, { "done", RES_DONE, FLAG_END } }; @@ -1939,13 +2071,20 @@ int reserved_word(o_string *dest, struct p_context *ctx) if (r->flag & FLAG_START) { struct p_context *new = xmalloc(sizeof(struct p_context)); debug_printf("push stack\n"); + if (ctx->w == RES_IN || ctx->w == RES_FOR) { + syntax(); + free(new); + ctx->w = RES_SNTX; + b_reset(dest); + return 1; + } *new = *ctx; /* physical copy */ initialize_context(ctx); ctx->stack=new; } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) { syntax(); ctx->w = RES_SNTX; - b_reset (dest); + b_reset(dest); return 1; } ctx->w=r->code; @@ -1953,6 +2092,7 @@ int reserved_word(o_string *dest, struct p_context *ctx) if (ctx->old_flag & FLAG_END) { struct p_context *old; debug_printf("pop stack\n"); + done_pipe(ctx,PIPE_SEQ); old = ctx->stack; old->child->group = ctx->list_head; old->child->subshell = 0; @@ -1986,7 +2126,7 @@ static int done_word(o_string *dest, struct p_context *ctx) syntax(); return 1; /* syntax error, groups and arglists don't mix */ } - if (!child->argv) { + if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) { debug_printf("checking %s for reserved-ness\n",dest->data); if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX; } @@ -2006,6 +2146,10 @@ static int done_word(o_string *dest, struct p_context *ctx) } else { child->argv = glob_target->gl_pathv; } + if (ctx->w == RES_FOR) { + done_word(dest,ctx); + done_pipe(ctx,PIPE_SEQ); + } return 0; } @@ -2041,8 +2185,10 @@ static int done_command(struct p_context *ctx) prog->group = NULL; prog->glob_result.gl_pathv = NULL; prog->family = pi; + prog->sp = 0; + ctx->child = prog; + prog->type = ctx->type; - ctx->child=prog; /* but ctx->pipe and ctx->list_head remain unchanged */ return 0; } @@ -2227,32 +2373,32 @@ static int parse_group(o_string *dest, struct p_context *ctx, /* 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) +static char *lookup_param(char *src) { - const char *p=NULL; - if (src->data) { - p = getenv(src->data); + char *p=NULL; + if (src) { + p = getenv(src); if (!p) - p = get_local_var(src->data); + p = get_local_var(src); } - if (p) parse_string(dest, ctx, p); /* recursion */ - b_free(src); + return p; } /* 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)) { + b_addchr(dest, SPECIAL_VAR_SYMBOL); + ctx->child->sp++; while(ch=b_peek(input),isalnum(ch) || ch=='_') { b_getch(input); - b_addchr(&alt,ch); + b_addchr(dest,ch); } - lookup_param(dest, ctx, &alt); + b_addchr(dest, SPECIAL_VAR_SYMBOL); } else if (isdigit(ch)) { i = ch-'0'; /* XXX is $0 special? */ if (i<global_argc) { @@ -2277,16 +2423,18 @@ static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *i advance = 1; break; case '{': + b_addchr(dest, SPECIAL_VAR_SYMBOL); + ctx->child->sp++; b_getch(input); /* XXX maybe someone will try to escape the '}' */ while(ch=b_getch(input),ch!=EOF && ch!='}') { - b_addchr(&alt,ch); + b_addchr(dest,ch); } if (ch != '}') { syntax(); return 1; } - lookup_param(dest, ctx, &alt); + b_addchr(dest, SPECIAL_VAR_SYMBOL); break; case '(': b_getch(input); @@ -2348,7 +2496,9 @@ int parse_stream(o_string *dest, struct p_context *ctx, b_addqchr(dest, ch, dest->quote); } else { if (m==2) { /* unquoted IFS */ - done_word(dest, ctx); + if (done_word(dest, ctx)) { + return 1; + } /* If we aren't performing a substitution, treat a newline as a * command separator. */ if (end_trigger != '\0' && ch=='\n') @@ -2509,30 +2659,46 @@ void update_ifs_map(void) /* most recursion does not come through here, the exeception is * from builtin_source() */ -int parse_stream_outer(struct in_str *inp) +int parse_stream_outer(struct in_str *inp, int flag) { struct p_context ctx; o_string temp=NULL_O_STRING; int rcode; do { + ctx.type = flag; initialize_context(&ctx); update_ifs_map(); + if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0); inp->promptmode=1; rcode = parse_stream(&temp, &ctx, inp, '\n'); - done_word(&temp, &ctx); - done_pipe(&ctx,PIPE_SEQ); - run_list(ctx.list_head); + if (rcode != 1 && ctx.old_flag != 0) { + syntax(); + } + if (rcode != 1 && ctx.old_flag == 0) { + done_word(&temp, &ctx); + done_pipe(&ctx,PIPE_SEQ); + run_list(ctx.list_head); + } else { + if (ctx.old_flag != 0) { + free(ctx.stack); + b_reset(&temp); + } + temp.nonnull = 0; + temp.quote = 0; + inp->p = NULL; + free_pipe_list(ctx.list_head,0); + } b_free(&temp); - } while (rcode != -1); /* loop on syntax errors, return on EOF */ + } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */ return 0; } -static int parse_string_outer(const char *s) +static int parse_string_outer(const char *s, int flag) { struct in_str input; setup_string_in_str(&input, s); - return parse_stream_outer(&input); + return parse_stream_outer(&input, flag); } static int parse_file_outer(FILE *f) @@ -2540,7 +2706,7 @@ static int parse_file_outer(FILE *f) int rcode; struct in_str input; setup_file_in_str(&input, f); - rcode = parse_stream_outer(&input); + rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON); return rcode; } @@ -2630,7 +2796,7 @@ int hush_main(int argc, char **argv) { global_argv = argv+optind; global_argc = argc-optind; - opt = parse_string_outer(optarg); + opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON); goto final_return; } break; @@ -2703,3 +2869,106 @@ int hush_main(int argc, char **argv) final_return: return(opt?opt:last_return_code); } + +static char *insert_var_value(char *inp) +{ + int res_str_len = 0; + int len; + int done = 0; + char *p, *p1, *res_str = NULL; + + while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) { + if (p != inp) { + len = p - inp; + res_str = xrealloc(res_str, (res_str_len + len)); + strncpy((res_str + res_str_len), inp, len); + res_str_len += len; + } + inp = ++p; + p = strchr(inp, SPECIAL_VAR_SYMBOL); + *p = '\0'; + if ((p1 = lookup_param(inp))) { + len = res_str_len + strlen(p1); + res_str = xrealloc(res_str, (1 + len)); + strcpy((res_str + res_str_len), p1); + res_str_len = len; + } + *p = SPECIAL_VAR_SYMBOL; + inp = ++p; + done = 1; + } + if (done) { + res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp))); + strcpy((res_str + res_str_len), inp); + while ((p = strchr(res_str, '\n'))) { + *p = ' '; + } + } + return (res_str == NULL) ? inp : res_str; +} + +static char **make_list_in(char **inp, char *name) +{ + int len, i; + int name_len = strlen(name); + int n = 0; + char **list; + char *p1, *p2, *p3; + + /* create list of variable values */ + list = xmalloc(sizeof(*list)); + for (i = 0; inp[i]; i++) { + p3 = insert_var_value(inp[i]); + p1 = p3; + while (*p1) { + if ((*p1 == ' ')) { + p1++; + continue; + } + if ((p2 = strchr(p1, ' '))) { + len = p2 - p1; + } else { + len = strlen(p1); + p2 = p1 + len; + } + /* we use n + 2 in realloc for list,because we add + * new element and then we will add NULL element */ + list = xrealloc(list, sizeof(*list) * (n + 2)); + list[n] = xmalloc(2 + name_len + len); + strcpy(list[n], name); + strcat(list[n], "="); + strncat(list[n], p1, len); + list[n++][name_len + len + 1] = '\0'; + p1 = p2; + } + if (p3 != inp[i]) free(p3); + } + list[n] = NULL; + return list; +} + +/* Make new string for parser */ +static char * make_string(char ** inp) +{ + char *p; + char *str = NULL; + int n; + int len = 2; + + for (n = 0; inp[n]; n++) { + p = insert_var_value(inp[n]); + str = xrealloc(str, (len + strlen(p))); + if (n) { + strcat(str, " "); + } else { + *str = '\0'; + } + strcat(str, p); + len = strlen(str) + 3; + if (p != inp[n]) free(p); + } + len = strlen(str); + *(str + len) = '\n'; + *(str + len + 1) = '\0'; + return str; +} |