1 /* vi: set sw=4 ts=4: */
3 * A prototype Bourne shell grammar parser.
4 * Intended to follow the original Thompson and Ritchie
5 * "small and simple is beautiful" philosophy, which
6 * incidentally is a good match to today's BusyBox.
8 * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
9 * Copyright (C) 2008,2009 Denys Vlasenko <vda.linux@googlemail.com>
12 * The parser routines proper are all original material, first
13 * written Dec 2000 and Jan 2001 by Larry Doolittle. The
14 * execution engine, the builtins, and much of the underlying
15 * support has been adapted from busybox-0.49pre's lash, which is
16 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
17 * written by Erik Andersen <andersen@codepoet.org>. That, in turn,
18 * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
19 * Troan, which they placed in the public domain. I don't know
20 * how much of the Johnson/Troan code has survived the repeated
24 * o_addchr derived from similar w_addchar function in glibc-2.2.
25 * parse_redirect, redirect_opt_num, and big chunks of main
26 * and many builtins derived from contributions by Erik Andersen.
27 * Miscellaneous bugfixes from Matt Kraai.
29 * There are two big (and related) architecture differences between
30 * this parser and the lash parser. One is that this version is
31 * actually designed from the ground up to understand nearly all
32 * of the Bourne grammar. The second, consequential change is that
33 * the parser and input reader have been turned inside out. Now,
34 * the parser is in control, and asks for input as needed. The old
35 * way had the input reader in control, and it asked for parsing to
36 * take place as needed. The new way makes it much easier to properly
37 * handle the recursion implicit in the various substitutions, especially
38 * across continuation lines.
40 * POSIX syntax not implemented:
42 * <(list) and >(list) Process Substitution
46 * Bash stuff (maybe optionally enable?):
47 * &> and >& redirection of stdout+stderr
49 * reserved words: [[ ]] function select
50 * substrings ${var:1:5}
53 * grep for "TODO" and fix (some of them are easy)
54 * change { and } from special chars to reserved words
55 * builtins: return, ulimit
56 * follow IFS rules more precisely, including update semantics
57 * figure out what to do with backslash-newline
58 * continuation lines, both explicit and implicit - done?
60 * ^Z handling (and explain it in comments for mere humans)
61 * separate job control from interactiveness
62 * (testcase: booting with init=/bin/hush does not show prompt (2009-04))
65 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
68 #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */
69 //TODO: pull in some .h and find out whether we have SINGLE_APPLET_MAIN?
70 //#include "applet_tables.h" doesn't work
72 /* #include <dmalloc.h> */
79 # define PIPE_BUF 4096 /* amount of buffering in a pipe */
82 #ifdef WANT_TO_TEST_NOMMU
87 # define USE_FOR_NOMMU(...) __VA_ARGS__
88 # define USE_FOR_MMU(...)
91 #if defined SINGLE_APPLET_MAIN
92 /* STANDALONE does not make sense, and won't compile */
93 #undef CONFIG_FEATURE_SH_STANDALONE
94 #undef ENABLE_FEATURE_SH_STANDALONE
95 #undef USE_FEATURE_SH_STANDALONE
96 #define SKIP_FEATURE_SH_STANDALONE(...) __VA_ARGS__
97 #define ENABLE_FEATURE_SH_STANDALONE 0
98 #define USE_FEATURE_SH_STANDALONE(...)
99 #define SKIP_FEATURE_SH_STANDALONE(...) __VA_ARGS__
102 #if !ENABLE_HUSH_INTERACTIVE
103 #undef ENABLE_FEATURE_EDITING
104 #define ENABLE_FEATURE_EDITING 0
105 #undef ENABLE_FEATURE_EDITING_FANCY_PROMPT
106 #define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
109 /* Do we support ANY keywords? */
110 #if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
111 #define HAS_KEYWORDS 1
112 #define IF_HAS_KEYWORDS(...) __VA_ARGS__
113 #define IF_HAS_NO_KEYWORDS(...)
115 #define HAS_KEYWORDS 0
116 #define IF_HAS_KEYWORDS(...)
117 #define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__
120 /* Keep unconditionally on for now */
123 #define ENABLE_HUSH_FUNCTIONS 0
126 /* If you comment out one of these below, it will be #defined later
127 * to perform debug printfs to stderr: */
128 #define debug_printf(...) do {} while (0)
129 /* Finer-grained debug switches */
130 #define debug_printf_parse(...) do {} while (0)
131 #define debug_print_tree(a, b) do {} while (0)
132 #define debug_printf_exec(...) do {} while (0)
133 #define debug_printf_env(...) do {} while (0)
134 #define debug_printf_jobs(...) do {} while (0)
135 #define debug_printf_expand(...) do {} while (0)
136 #define debug_printf_glob(...) do {} while (0)
137 #define debug_printf_list(...) do {} while (0)
138 #define debug_printf_subst(...) do {} while (0)
139 #define debug_printf_clean(...) do {} while (0)
142 #define debug_printf(...) fprintf(stderr, __VA_ARGS__)
145 #ifndef debug_printf_parse
146 #define debug_printf_parse(...) fprintf(stderr, __VA_ARGS__)
149 #ifndef debug_printf_exec
150 #define debug_printf_exec(...) fprintf(stderr, __VA_ARGS__)
153 #ifndef debug_printf_env
154 #define debug_printf_env(...) fprintf(stderr, __VA_ARGS__)
157 #ifndef debug_printf_jobs
158 #define debug_printf_jobs(...) fprintf(stderr, __VA_ARGS__)
164 #ifndef debug_printf_expand
165 #define debug_printf_expand(...) fprintf(stderr, __VA_ARGS__)
166 #define DEBUG_EXPAND 1
168 #define DEBUG_EXPAND 0
171 #ifndef debug_printf_glob
172 #define debug_printf_glob(...) fprintf(stderr, __VA_ARGS__)
178 #ifndef debug_printf_list
179 #define debug_printf_list(...) fprintf(stderr, __VA_ARGS__)
182 #ifndef debug_printf_subst
183 #define debug_printf_subst(...) fprintf(stderr, __VA_ARGS__)
186 #ifndef debug_printf_clean
187 /* broken, of course, but OK for testing */
188 static const char *indenter(int i)
190 static const char blanks[] ALIGN1 =
192 return &blanks[sizeof(blanks) - i - 1];
194 #define debug_printf_clean(...) fprintf(stderr, __VA_ARGS__)
195 #define DEBUG_CLEAN 1
197 #define DEBUG_CLEAN 0
201 static void debug_print_strings(const char *prefix, char **vv)
203 fprintf(stderr, "%s:\n", prefix);
205 fprintf(stderr, " '%s'\n", *vv++);
208 #define debug_print_strings(prefix, vv) ((void)0)
212 * Leak hunting. Use hush_leaktool.sh for post-processing.
214 #ifdef FOR_HUSH_LEAKTOOL
215 static void *xxmalloc(int lineno, size_t size)
217 void *ptr = xmalloc((size + 0xff) & ~0xff);
218 fdprintf(2, "line %d: malloc %p\n", lineno, ptr);
221 static void *xxrealloc(int lineno, void *ptr, size_t size)
223 ptr = xrealloc(ptr, (size + 0xff) & ~0xff);
224 fdprintf(2, "line %d: realloc %p\n", lineno, ptr);
227 static char *xxstrdup(int lineno, const char *str)
229 char *ptr = xstrdup(str);
230 fdprintf(2, "line %d: strdup %p\n", lineno, ptr);
233 static void xxfree(void *ptr)
235 fdprintf(2, "free %p\n", ptr);
238 #define xmalloc(s) xxmalloc(__LINE__, s)
239 #define xrealloc(p, s) xxrealloc(__LINE__, p, s)
240 #define xstrdup(s) xxstrdup(__LINE__, s)
241 #define free(p) xxfree(p)
245 #define ERR_PTR ((void*)(long)1)
247 static const char hush_version_str[] ALIGN1 = "HUSH_VERSION="BB_VER;
249 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
251 #define SPECIAL_VAR_SYMBOL 3
253 typedef enum redir_type {
254 REDIRECT_INVALID = 0,
256 REDIRECT_OVERWRITE = 2,
258 REDIRECT_HEREDOC = 4,
260 REDIRECT_HEREDOC2 = 6, /* REDIRECT_HEREDOC after heredoc load */
263 /* The descrip member of this structure is only used to make
264 * debugging output pretty */
265 static const struct {
267 signed char default_fd;
271 { O_RDONLY, 0, "<" },
272 { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
273 { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
274 { O_RDONLY, 0, "<<" },
275 { O_CREAT|O_RDWR, 1, "<>" },
276 /* Should not be needed. Bogus default_fd helps in debugging */
277 /* { O_RDONLY, 77, "<<" }, */
280 typedef enum reserved_style {
289 #if ENABLE_HUSH_LOOPS
296 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
301 /* two pseudo-keywords support contrived "case" syntax: */
302 RES_MATCH , /* "word)" */
303 RES_CASEI , /* "this command is inside CASE" */
310 typedef struct o_string {
312 int length; /* position where data is appended */
314 /* Protect newly added chars against globbing
315 * (by prepending \ to *, ?, [, \) */
319 smallint has_empty_slot;
320 smallint o_assignment; /* 0:maybe, 1:yes, 2:no */
323 MAYBE_ASSIGNMENT = 0,
324 DEFINITELY_ASSIGNMENT = 1,
326 WORD_IS_KEYWORD = 3, /* not assigment, but next word may be: "if v=xyz cmd;" */
328 /* Used for initialization: o_string foo = NULL_O_STRING; */
329 #define NULL_O_STRING { NULL }
331 /* I can almost use ordinary FILE*. Is open_memstream() universally
332 * available? Where is it documented? */
333 typedef struct in_str {
335 /* eof_flag=1: last char in ->p is really an EOF */
336 char eof_flag; /* meaningless if ->p == NULL */
338 #if ENABLE_HUSH_INTERACTIVE
340 smallint promptmode; /* 0: PS1, 1: PS2 */
343 int (*get) (struct in_str *);
344 int (*peek) (struct in_str *);
346 #define i_getch(input) ((input)->get(input))
347 #define i_peek(input) ((input)->peek(input))
349 struct redir_struct {
350 struct redir_struct *next;
351 char *rd_filename; /* filename */
352 int fd; /* file descriptor being redirected */
353 int dup; /* -1, or file descriptor being duplicated */
354 smallint /*enum redir_type*/ rd_type;
358 pid_t pid; /* 0 if exited */
359 int assignment_cnt; /* how many argv[i] are assignments? */
360 smallint is_stopped; /* is the command currently running? */
361 smallint grp_type; /* GRP_xxx */
362 struct pipe *group; /* if non-NULL, this "command" is { list },
363 * ( list ), or a compound statement */
365 char *group_as_string;
367 char **argv; /* command name and arguments */
368 struct redir_struct *redirects; /* I/O redirections */
370 /* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
371 * and on execution these are substituted with their values.
372 * Substitution can make _several_ words out of one argv[n]!
373 * Example: argv[0]=='.^C*^C.' here: echo .$*.
374 * References of the form ^C`cmd arg^C are `cmd arg` substitutions.
377 #define GRP_SUBSHELL 1
378 #if ENABLE_HUSH_FUNCTIONS
379 #define GRP_FUNCTION 2
384 int num_cmds; /* total number of commands in job */
385 int alive_cmds; /* number of commands running (not exited) */
386 int stopped_cmds; /* number of commands alive, but stopped */
388 int jobid; /* job number */
389 pid_t pgrp; /* process group ID for the job */
390 char *cmdtext; /* name of job */
392 struct command *cmds; /* array of commands in pipe */
393 smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
394 IF_HAS_KEYWORDS(smallint pi_inverted;) /* "! cmd | cmd" */
395 IF_HAS_KEYWORDS(smallint res_word;) /* needed for if, for, while, until... */
397 typedef enum pipe_style {
404 /* This holds pointers to the various results of parsing */
405 struct parse_context {
406 /* linked list of pipes */
407 struct pipe *list_head;
408 /* last pipe (being constructed right now) */
410 /* last command in pipe (being constructed right now) */
411 struct command *command;
412 /* last redirect in command->redirects list */
413 struct redir_struct *pending_redirect;
419 smallint ctx_inverted; /* "! cmd | cmd" */
421 smallint ctx_dsemicolon; /* ";;" seen */
423 /* bitmask of FLAG_xxx, for figuring out valid reserved words */
425 /* group we are enclosed in:
426 * example: "if pipe1; pipe2; then pipe3; fi"
427 * when we see "if" or "then", we malloc and copy current context,
428 * and make ->stack point to it. then we parse pipeN.
429 * when closing "then" / fi" / whatever is found,
430 * we move list_head into ->stack->command->group,
431 * copy ->stack into current context, and delete ->stack.
432 * (parsing of { list } and ( list ) doesn't use this method)
434 struct parse_context *stack;
438 /* On program start, environ points to initial environment.
439 * putenv adds new pointers into it, unsetenv removes them.
440 * Neither of these (de)allocates the strings.
441 * setenv allocates new strings in malloc space and does putenv,
442 * and thus setenv is unusable (leaky) for shell's purposes */
443 #define setenv(...) setenv_is_leaky_dont_use()
445 struct variable *next;
446 char *varstr; /* points to "name=" portion */
447 int max_len; /* if > 0, name is part of initial env; else name is malloced */
448 smallint flg_export; /* putenv should be done on this var */
449 smallint flg_read_only;
458 /* "Globals" within this file */
459 /* Sorted roughly by size (smaller offsets == smaller code) */
461 #if ENABLE_HUSH_INTERACTIVE
462 /* 'interactive_fd' is a fd# open to ctty, if we have one
463 * _AND_ if we decided to act interactively */
467 #define G_interactive_fd (G.interactive_fd)
469 #define G_interactive_fd 0
471 #if ENABLE_FEATURE_EDITING
472 line_input_t *line_input_state;
478 pid_t saved_tty_pgrp;
480 struct pipe *job_list;
481 struct pipe *toplevel_list;
482 //// smallint ctrl_z_flag;
484 smallint flag_SIGINT;
485 #if ENABLE_HUSH_LOOPS
486 smallint flag_break_continue;
489 /* These four support $?, $#, and $1 */
490 smalluint last_exitcode;
491 /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */
492 smalluint global_args_malloced;
493 /* how many non-NULL argv's we have. NB: $# + 1 */
497 char *argv0_for_re_execing;
498 char **argv_from_re_execing;
500 #if ENABLE_HUSH_LOOPS
501 unsigned depth_break_continue;
502 unsigned depth_of_loop;
506 struct variable *top_var; /* = &G.shell_ver (set in main()) */
507 struct variable shell_ver;
508 /* Signal and trap handling */
509 // unsigned count_SIGCHLD;
510 // unsigned handled_SIGCHLD;
511 /* which signals have non-DFL handler (even with no traps set)? */
512 unsigned non_DFL_mask;
513 char **traps; /* char *traps[NSIG] */
514 sigset_t blocked_set;
515 sigset_t inherited_set;
516 char user_input_buf[ENABLE_FEATURE_EDITING ? BUFSIZ : 2];
517 #if ENABLE_FEATURE_SH_STANDALONE
518 struct nofork_save_area nofork_save;
521 sigjmp_buf toplevel_jb;
524 #define G (*ptr_to_globals)
525 /* Not #defining name to G.name - this quickly gets unwieldy
526 * (too many defines). Also, I actually prefer to see when a variable
527 * is global, thus "G." prefix is a useful hint */
528 #define INIT_G() do { \
529 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
533 /* Function prototypes for builtins */
534 static int builtin_cd(char **argv);
535 static int builtin_echo(char **argv);
536 static int builtin_eval(char **argv);
537 static int builtin_exec(char **argv);
538 static int builtin_exit(char **argv);
539 static int builtin_export(char **argv);
541 static int builtin_fg_bg(char **argv);
542 static int builtin_jobs(char **argv);
545 static int builtin_help(char **argv);
547 static int builtin_pwd(char **argv);
548 static int builtin_read(char **argv);
549 static int builtin_test(char **argv);
550 static int builtin_trap(char **argv);
551 static int builtin_true(char **argv);
552 static int builtin_set(char **argv);
553 static int builtin_shift(char **argv);
554 static int builtin_source(char **argv);
555 static int builtin_umask(char **argv);
556 static int builtin_unset(char **argv);
557 static int builtin_wait(char **argv);
558 #if ENABLE_HUSH_LOOPS
559 static int builtin_break(char **argv);
560 static int builtin_continue(char **argv);
563 /* Table of built-in functions. They can be forked or not, depending on
564 * context: within pipes, they fork. As simple commands, they do not.
565 * When used in non-forking context, they can change global variables
566 * in the parent shell process. If forked, of course they cannot.
567 * For example, 'unset foo | whatever' will parse and run, but foo will
568 * still be set at the end. */
569 struct built_in_command {
571 int (*function)(char **argv);
574 #define BLTIN(cmd, func, help) { cmd, func, help }
576 #define BLTIN(cmd, func, help) { cmd, func }
580 /* For now, echo and test are unconditionally enabled.
581 * Maybe make it configurable? */
582 static const struct built_in_command bltins[] = {
583 BLTIN("." , builtin_source , "Run commands in a file"),
584 BLTIN(":" , builtin_true , "No-op"),
585 BLTIN("[" , builtin_test , "Test condition"),
587 BLTIN("bg" , builtin_fg_bg , "Resume a job in the background"),
589 #if ENABLE_HUSH_LOOPS
590 BLTIN("break" , builtin_break , "Exit from a loop"),
592 BLTIN("cd" , builtin_cd , "Change directory"),
593 #if ENABLE_HUSH_LOOPS
594 BLTIN("continue", builtin_continue, "Start new loop iteration"),
596 BLTIN("echo" , builtin_echo , "Write to stdout"),
597 BLTIN("eval" , builtin_eval , "Construct and run shell command"),
598 BLTIN("exec" , builtin_exec , "Execute command, don't return to shell"),
599 BLTIN("exit" , builtin_exit , "Exit"),
600 BLTIN("export" , builtin_export , "Set environment variable"),
602 BLTIN("fg" , builtin_fg_bg , "Bring job into the foreground"),
605 BLTIN("help" , builtin_help , "List shell built-in commands"),
608 BLTIN("jobs" , builtin_jobs , "List active jobs"),
610 BLTIN("pwd" , builtin_pwd , "Print current directory"),
611 BLTIN("read" , builtin_read , "Input environment variable"),
612 // BLTIN("return" , builtin_return , "Return from a function"),
613 BLTIN("set" , builtin_set , "Set/unset shell local variables"),
614 BLTIN("shift" , builtin_shift , "Shift positional parameters"),
615 BLTIN("test" , builtin_test , "Test condition"),
616 BLTIN("trap" , builtin_trap , "Trap signals"),
617 // BLTIN("ulimit" , builtin_return , "Control resource limits"),
618 BLTIN("umask" , builtin_umask , "Set file creation mask"),
619 BLTIN("unset" , builtin_unset , "Unset environment variable"),
620 BLTIN("wait" , builtin_wait , "Wait for process"),
624 static void maybe_die(const char *notice, const char *msg)
626 /* Was using fancy stuff:
627 * (G_interactive_fd ? bb_error_msg : bb_error_msg_and_die)(...params...)
628 * but it SEGVs. ?! Oh well... explicit temp ptr works around that */
629 void FAST_FUNC (*fp)(const char *s, ...) = bb_error_msg_and_die;
630 #if ENABLE_HUSH_INTERACTIVE
631 if (G_interactive_fd)
634 fp(msg ? "%s: %s" : notice, notice, msg);
637 #define syntax(msg) maybe_die("syntax error", msg);
639 /* Debug -- trick gcc to expand __LINE__ and convert to string */
640 #define __syntax(msg, line) maybe_die("syntax error hush.c:" # line, msg)
641 #define _syntax(msg, line) __syntax(msg, line)
642 #define syntax(msg) _syntax(msg, __LINE__)
646 static int glob_needed(const char *s)
651 if (*s == '*' || *s == '[' || *s == '?')
658 static int is_assignment(const char *s)
660 if (!s || !(isalpha(*s) || *s == '_'))
663 while (isalnum(*s) || *s == '_')
668 /* Replace each \x with x in place, return ptr past NUL. */
669 static char *unbackslash(char *src)
675 if ((*dst++ = *src++) == '\0')
681 static char **add_strings_to_strings(char **strings, char **add, int need_to_dup)
702 v = xrealloc(strings, (count1 + count2 + 1) * sizeof(char*));
703 v[count1 + count2] = NULL;
706 v[count1 + i] = (need_to_dup ? xstrdup(add[i]) : add[i]);
710 static char **add_string_to_strings(char **strings, char *add)
715 return add_strings_to_strings(strings, v, /*dup:*/ 0);
718 static void putenv_all(char **strings)
723 debug_printf_env("putenv '%s'\n", *strings);
728 static char **putenv_all_and_save_old(char **strings)
738 eq = strchr(*strings, '=');
741 v = getenv(*strings);
744 /* v points to VAL in VAR=VAL, go back to VAR */
745 v -= (eq - *strings) + 1;
746 old = add_string_to_strings(old, v);
755 static void free_strings_and_unsetenv(char **strings, int unset)
765 debug_printf_env("unsetenv '%s'\n", *v);
773 static void free_strings(char **strings)
775 free_strings_and_unsetenv(strings, 0);
779 /* Basic theory of signal handling in shell
780 * ========================================
781 * This does not describe what hush does, rather, it is current understanding
782 * what it _should_ do. If it doesn't, it's a bug.
783 * http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap
785 * Signals are handled only after each pipe ("cmd | cmd | cmd" thing)
786 * is finished or backgrounded. It is the same in interactive and
787 * non-interactive shells, and is the same regardless of whether
788 * a user trap handler is installed or a shell special one is in effect.
789 * ^C or ^Z from keyboard seem to execute "at once" because it usually
790 * backgrounds (i.e. stops) or kills all members of currently running
793 * Wait builtin in interruptible by signals for which user trap is set
794 * or by SIGINT in interactive shell.
796 * Trap handlers will execute even within trap handlers. (right?)
798 * User trap handlers are forgotten when subshell ("(cmd)") is entered. [TODO]
800 * If job control is off, backgrounded commands ("cmd &")
801 * have SIGINT, SIGQUIT set to SIG_IGN.
803 * Commands run in command substitution ("`cmd`")
804 * have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN.
806 * Ordinary commands have signals set to SIG_IGN/DFL set as inherited
807 * by the shell from its parent.
809 * Siganls which differ from SIG_DFL action
810 * (note: child (i.e., [v]forked) shell is not an interactive shell):
813 * SIGTERM (interactive): ignore
814 * SIGHUP (interactive):
815 * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit
816 * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore
817 * (note that ^Z is handled not by trapping SIGTSTP, but by seeing
818 * that all pipe members are stopped) (right?)
819 * SIGINT (interactive): wait for last pipe, ignore the rest
820 * of the command line, show prompt. NB: ^C does not send SIGINT
821 * to interactive shell while shell is waiting for a pipe,
822 * since shell is bg'ed (is not in foreground process group).
823 * (check/expand this)
824 * Example 1: this waits 5 sec, but does not execute ls:
825 * "echo $$; sleep 5; ls -l" + "kill -INT <pid>"
826 * Example 2: this does not wait and does not execute ls:
827 * "echo $$; sleep 5 & wait; ls -l" + "kill -INT <pid>"
828 * Example 3: this does not wait 5 sec, but executes ls:
829 * "sleep 5; ls -l" + press ^C
831 * (What happens to signals which are IGN on shell start?)
832 * (What happens with signal mask on shell start?)
834 * Implementation in hush
835 * ======================
836 * We use in-kernel pending signal mask to determine which signals were sent.
837 * We block all signals which we don't want to take action immediately,
838 * i.e. we block all signals which need to have special handling as described
839 * above, and all signals which have traps set.
840 * After each pipe execution, we extract any pending signals via sigtimedwait()
843 * unsigned non_DFL_mask: a mask of such "special" signals
844 * sigset_t blocked_set: current blocked signal set
847 * clear bit in blocked_set unless it is also in non_DFL_mask
848 * "trap 'cmd' SIGxxx":
849 * set bit in blocked_set (even if 'cmd' is '')
850 * after [v]fork, if we plan to be a shell:
851 * nothing for {} child shell (say, "true | { true; true; } | true")
852 * unset all traps if () shell. [TODO]
853 * after [v]fork, if we plan to exec:
854 * POSIX says pending signal mask is cleared in child - no need to clear it.
855 * Restore blocked signal set to one inherited by shell just prior to exec.
857 * Note: as a result, we do not use signal handlers much. The only uses
858 * are to count SIGCHLDs [disabled - bug somewhere, + bloat]
859 * and to restore tty pgrp on signal-induced exit.
862 //static void SIGCHLD_handler(int sig UNUSED_PARAM)
864 // G.count_SIGCHLD++;
867 static int check_and_run_traps(int sig)
869 static const struct timespec zero_timespec = { 0, 0 };
870 smalluint save_rcode;
876 sig = sigtimedwait(&G.blocked_set, NULL, &zero_timespec);
881 if (G.traps && G.traps[sig]) {
882 if (G.traps[sig][0]) {
883 /* We have user-defined handler */
884 char *argv[] = { NULL, xstrdup(G.traps[sig]), NULL };
885 save_rcode = G.last_exitcode;
888 G.last_exitcode = save_rcode;
889 } /* else: "" trap, ignoring signal */
892 /* not a trap: special action */
895 // G.count_SIGCHLD++;
904 default: /* ignored: */
905 /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */
913 /* Restores tty foreground process group, and exits.
914 * May be called as signal handler for fatal signal
915 * (will faithfully resend signal to itself, producing correct exit state)
916 * or called directly with -EXITCODE.
917 * We also call it if xfunc is exiting. */
918 static void sigexit(int sig) NORETURN;
919 static void sigexit(int sig)
921 /* Disable all signals: job control, SIGPIPE, etc. */
922 sigprocmask_allsigs(SIG_BLOCK);
924 /* Careful: we can end up here after [v]fork. Do not restore
925 * tty pgrp then, only top-level shell process does that */
926 if (G_interactive_fd && getpid() == G.root_pid)
927 tcsetpgrp(G_interactive_fd, G.saved_tty_pgrp);
929 /* Not a signal, just exit */
933 kill_myself_with_sig(sig); /* does not return */
937 /* Restores tty foreground process group, and exits. */
938 static void hush_exit(int exitcode) NORETURN;
939 static void hush_exit(int exitcode)
941 if (G.traps && G.traps[0] && G.traps[0][0]) {
942 char *argv[] = { NULL, xstrdup(G.traps[0]), NULL };
943 //TODO: do we need to prevent recursion?
949 fflush(NULL); /* flush all streams */
950 sigexit(- (exitcode & 0xff));
957 static const char *set_cwd(void)
959 /* xrealloc_getcwd_or_warn(arg) calls free(arg),
960 * we must not try to free(bb_msg_unknown) */
961 if (G.cwd == bb_msg_unknown)
963 G.cwd = xrealloc_getcwd_or_warn((char *)G.cwd);
965 G.cwd = bb_msg_unknown;
970 /* Get/check local shell variables */
971 static struct variable *get_local_var(const char *name)
973 struct variable *cur;
979 for (cur = G.top_var; cur; cur = cur->next) {
980 if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=')
986 static const char *get_local_var_value(const char *src)
988 struct variable *var = get_local_var(src);
990 return strchr(var->varstr, '=') + 1;
994 /* str holds "NAME=VAL" and is expected to be malloced.
995 * We take ownership of it.
999 * -1: if NAME is set, leave export status alone
1000 * if NAME is not set, do not export
1001 * flg_read_only is set only when we handle -R var=val
1004 #define set_local_var(str, flg_export, flg_read_only) \
1005 set_local_var(str, flg_export)
1007 static int set_local_var(char *str, int flg_export, int flg_read_only)
1009 struct variable *cur;
1013 value = strchr(str, '=');
1014 if (!value) { /* not expected to ever happen? */
1019 name_len = value - str + 1; /* including '=' */
1020 cur = G.top_var; /* cannot be NULL (we have HUSH_VERSION and it's RO) */
1022 if (strncmp(cur->varstr, str, name_len) != 0) {
1024 /* Bail out. Note that now cur points
1025 * to last var in linked list */
1031 /* We found an existing var with this name */
1033 if (cur->flg_read_only) {
1037 bb_error_msg("%s: readonly variable", str);
1041 debug_printf_env("%s: unsetenv '%s'\n", __func__, str);
1042 unsetenv(str); /* just in case */
1044 if (strcmp(cur->varstr, str) == 0) {
1049 if (cur->max_len >= strlen(str)) {
1050 /* This one is from startup env, reuse space */
1051 strcpy(cur->varstr, str);
1054 /* max_len == 0 signifies "malloced" var, which we can
1055 * (and has to) free */
1059 goto set_str_and_exp;
1062 /* Not found - create next variable struct */
1063 cur->next = xzalloc(sizeof(*cur));
1069 cur->flg_read_only = flg_read_only;
1072 if (flg_export == 1)
1073 cur->flg_export = 1;
1074 if (cur->flg_export) {
1075 debug_printf_env("%s: putenv '%s'\n", __func__, cur->varstr);
1076 return putenv(cur->varstr);
1081 static int unset_local_var(const char *name)
1083 struct variable *cur;
1084 struct variable *prev = prev; /* for gcc */
1088 return EXIT_SUCCESS;
1089 name_len = strlen(name);
1092 if (strncmp(cur->varstr, name, name_len) == 0 && cur->varstr[name_len] == '=') {
1093 if (cur->flg_read_only) {
1094 bb_error_msg("%s: readonly variable", name);
1095 return EXIT_FAILURE;
1097 /* prev is ok to use here because 1st variable, HUSH_VERSION,
1098 * is ro, and we cannot reach this code on the 1st pass */
1099 prev->next = cur->next;
1100 debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr);
1101 bb_unsetenv(cur->varstr);
1105 return EXIT_SUCCESS;
1110 return EXIT_SUCCESS;
1113 #if ENABLE_SH_MATH_SUPPORT
1114 #define is_name(c) ((c) == '_' || isalpha((unsigned char)(c)))
1115 #define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c)))
1116 static char *endofname(const char *name)
1124 if (!is_in_name(*p))
1130 static void arith_set_local_var(const char *name, const char *val, int flags)
1132 /* arith code doesnt malloc space, so do it for it */
1133 char *var = xasprintf("%s=%s", name, val);
1134 set_local_var(var, flags, 0);
1142 static int static_get(struct in_str *i)
1151 static int static_peek(struct in_str *i)
1156 #if ENABLE_HUSH_INTERACTIVE
1158 static void cmdedit_set_initial_prompt(void)
1160 if (ENABLE_FEATURE_EDITING_FANCY_PROMPT) {
1161 G.PS1 = getenv("PS1");
1168 static const char* setup_prompt_string(int promptmode)
1170 const char *prompt_str;
1171 debug_printf("setup_prompt_string %d ", promptmode);
1172 if (!ENABLE_FEATURE_EDITING_FANCY_PROMPT) {
1173 /* Set up the prompt */
1174 if (promptmode == 0) { /* PS1 */
1176 G.PS1 = xasprintf("%s %c ", G.cwd, (geteuid() != 0) ? '$' : '#');
1181 prompt_str = (promptmode == 0) ? G.PS1 : G.PS2;
1182 debug_printf("result '%s'\n", prompt_str);
1186 static void get_user_input(struct in_str *i)
1189 const char *prompt_str;
1191 prompt_str = setup_prompt_string(i->promptmode);
1192 #if ENABLE_FEATURE_EDITING
1193 /* Enable command line editing only while a command line
1194 * is actually being read */
1197 /* buglet: SIGINT will not make new prompt to appear _at once_,
1198 * only after <Enter>. (^C will work) */
1199 r = read_line_input(prompt_str, G.user_input_buf, BUFSIZ-1, G.line_input_state);
1200 /* catch *SIGINT* etc (^C is handled by read_line_input) */
1201 check_and_run_traps(0);
1202 } while (r == 0 || G.flag_SIGINT); /* repeat if ^C or SIGINT */
1203 i->eof_flag = (r < 0);
1204 if (i->eof_flag) { /* EOF/error detected */
1205 G.user_input_buf[0] = EOF; /* yes, it will be truncated, it's ok */
1206 G.user_input_buf[1] = '\0';
1211 fputs(prompt_str, stdout);
1213 G.user_input_buf[0] = r = fgetc(i->file);
1214 /*G.user_input_buf[1] = '\0'; - already is and never changed */
1215 //do we need check_and_run_traps(0)? (maybe only if stdin)
1216 } while (G.flag_SIGINT);
1217 i->eof_flag = (r == EOF);
1219 i->p = G.user_input_buf;
1222 #endif /* INTERACTIVE */
1224 /* This is the magic location that prints prompts
1225 * and gets data back from the user */
1226 static int file_get(struct in_str *i)
1230 /* If there is data waiting, eat it up */
1231 if (i->p && *i->p) {
1232 #if ENABLE_HUSH_INTERACTIVE
1236 if (i->eof_flag && !*i->p)
1238 /* note: ch is never NUL */
1240 /* need to double check i->file because we might be doing something
1241 * more complicated by now, like sourcing or substituting. */
1242 #if ENABLE_HUSH_INTERACTIVE
1243 if (G_interactive_fd && i->promptme && i->file == stdin) {
1246 } while (!*i->p); /* need non-empty line */
1247 i->promptmode = 1; /* PS2 */
1252 do ch = fgetc(i->file); while (ch == '\0');
1254 debug_printf("file_get: got '%c' %d\n", ch, ch);
1255 #if ENABLE_HUSH_INTERACTIVE
1262 /* All callers guarantee this routine will never
1263 * be used right after a newline, so prompting is not needed.
1265 static int file_peek(struct in_str *i)
1268 if (i->p && *i->p) {
1269 if (i->eof_flag && !i->p[1])
1272 /* note: ch is never NUL */
1274 do ch = fgetc(i->file); while (ch == '\0');
1275 i->eof_flag = (ch == EOF);
1276 i->peek_buf[0] = ch;
1277 i->peek_buf[1] = '\0';
1279 debug_printf("file_peek: got '%c' %d\n", ch, ch);
1283 static void setup_file_in_str(struct in_str *i, FILE *f)
1285 i->peek = file_peek;
1287 #if ENABLE_HUSH_INTERACTIVE
1289 i->promptmode = 0; /* PS1 */
1295 static void setup_string_in_str(struct in_str *i, const char *s)
1297 i->peek = static_peek;
1298 i->get = static_get;
1299 #if ENABLE_HUSH_INTERACTIVE
1301 i->promptmode = 0; /* PS1 */
1311 #define B_CHUNK (32 * sizeof(char*))
1313 static void o_reset(o_string *o)
1321 static void o_free(o_string *o)
1324 memset(o, 0, sizeof(*o));
1327 static ALWAYS_INLINE void o_free_unsafe(o_string *o)
1332 static void o_grow_by(o_string *o, int len)
1334 if (o->length + len > o->maxlen) {
1335 o->maxlen += (2*len > B_CHUNK ? 2*len : B_CHUNK);
1336 o->data = xrealloc(o->data, 1 + o->maxlen);
1340 static void o_addchr(o_string *o, int ch)
1342 debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o);
1344 o->data[o->length] = ch;
1346 o->data[o->length] = '\0';
1349 static void o_addblock(o_string *o, const char *str, int len)
1352 memcpy(&o->data[o->length], str, len);
1354 o->data[o->length] = '\0';
1358 static void o_addstr(o_string *o, const char *str)
1360 o_addblock(o, str, strlen(str));
1364 static void o_addstr_with_NUL(o_string *o, const char *str)
1366 o_addblock(o, str, strlen(str) + 1);
1369 static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len)
1374 && (*str != '*' && *str != '?' && *str != '[')
1382 /* My analysis of quoting semantics tells me that state information
1383 * is associated with a destination, not a source.
1385 static void o_addqchr(o_string *o, int ch)
1388 char *found = strchr("*?[\\", ch);
1393 o->data[o->length] = '\\';
1396 o->data[o->length] = ch;
1398 o->data[o->length] = '\0';
1401 static void o_addQchr(o_string *o, int ch)
1404 if (o->o_escape && strchr("*?[\\", ch)) {
1406 o->data[o->length] = '\\';
1410 o->data[o->length] = ch;
1412 o->data[o->length] = '\0';
1415 static void o_addQstr(o_string *o, const char *str, int len)
1418 o_addblock(o, str, len);
1424 int ordinary_cnt = strcspn(str, "*?[\\");
1425 if (ordinary_cnt > len) /* paranoia */
1427 o_addblock(o, str, ordinary_cnt);
1428 if (ordinary_cnt == len)
1430 str += ordinary_cnt;
1431 len -= ordinary_cnt + 1; /* we are processing + 1 char below */
1435 if (ch) { /* it is necessarily one of "*?[\\" */
1437 o->data[o->length] = '\\';
1441 o->data[o->length] = ch;
1443 o->data[o->length] = '\0';
1447 /* A special kind of o_string for $VAR and `cmd` expansion.
1448 * It contains char* list[] at the beginning, which is grown in 16 element
1449 * increments. Actual string data starts at the next multiple of 16 * (char*).
1450 * list[i] contains an INDEX (int!) into this string data.
1451 * It means that if list[] needs to grow, data needs to be moved higher up
1452 * but list[i]'s need not be modified.
1453 * NB: remembering how many list[i]'s you have there is crucial.
1454 * o_finalize_list() operation post-processes this structure - calculates
1455 * and stores actual char* ptrs in list[]. Oh, it NULL terminates it as well.
1457 #if DEBUG_EXPAND || DEBUG_GLOB
1458 static void debug_print_list(const char *prefix, o_string *o, int n)
1460 char **list = (char**)o->data;
1461 int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
1463 fprintf(stderr, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d\n",
1464 prefix, list, n, string_start, o->length, o->maxlen);
1466 fprintf(stderr, " list[%d]=%d '%s' %p\n", i, (int)list[i],
1467 o->data + (int)list[i] + string_start,
1468 o->data + (int)list[i] + string_start);
1472 const char *p = o->data + (int)list[n - 1] + string_start;
1473 fprintf(stderr, " total_sz:%ld\n", (long)((p + strlen(p) + 1) - o->data));
1477 #define debug_print_list(prefix, o, n) ((void)0)
1480 /* n = o_save_ptr_helper(str, n) "starts new string" by storing an index value
1481 * in list[n] so that it points past last stored byte so far.
1482 * It returns n+1. */
1483 static int o_save_ptr_helper(o_string *o, int n)
1485 char **list = (char**)o->data;
1489 if (!o->has_empty_slot) {
1490 string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
1491 string_len = o->length - string_start;
1492 if (!(n & 0xf)) { /* 0, 0x10, 0x20...? */
1493 debug_printf_list("list[%d]=%d string_start=%d (growing)\n", n, string_len, string_start);
1494 /* list[n] points to string_start, make space for 16 more pointers */
1495 o->maxlen += 0x10 * sizeof(list[0]);
1496 o->data = xrealloc(o->data, o->maxlen + 1);
1497 list = (char**)o->data;
1498 memmove(list + n + 0x10, list + n, string_len);
1499 o->length += 0x10 * sizeof(list[0]);
1501 debug_printf_list("list[%d]=%d string_start=%d\n",
1502 n, string_len, string_start);
1505 /* We have empty slot at list[n], reuse without growth */
1506 string_start = ((n+1 + 0xf) & ~0xf) * sizeof(list[0]); /* NB: n+1! */
1507 string_len = o->length - string_start;
1508 debug_printf_list("list[%d]=%d string_start=%d (empty slot)\n",
1509 n, string_len, string_start);
1510 o->has_empty_slot = 0;
1512 list[n] = (char*)(ptrdiff_t)string_len;
1516 /* "What was our last o_save_ptr'ed position (byte offset relative o->data)?" */
1517 static int o_get_last_ptr(o_string *o, int n)
1519 char **list = (char**)o->data;
1520 int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
1522 return ((int)(ptrdiff_t)list[n-1]) + string_start;
1525 /* o_glob performs globbing on last list[], saving each result
1526 * as a new list[]. */
1527 static int o_glob(o_string *o, int n)
1533 debug_printf_glob("start o_glob: n:%d o->data:%p\n", n, o->data);
1535 return o_save_ptr_helper(o, n);
1536 pattern = o->data + o_get_last_ptr(o, n);
1537 debug_printf_glob("glob pattern '%s'\n", pattern);
1538 if (!glob_needed(pattern)) {
1540 o->length = unbackslash(pattern) - o->data;
1541 debug_printf_glob("glob pattern '%s' is literal\n", pattern);
1542 return o_save_ptr_helper(o, n);
1545 memset(&globdata, 0, sizeof(globdata));
1546 gr = glob(pattern, 0, NULL, &globdata);
1547 debug_printf_glob("glob('%s'):%d\n", pattern, gr);
1548 if (gr == GLOB_NOSPACE)
1549 bb_error_msg_and_die("out of memory during glob");
1550 if (gr == GLOB_NOMATCH) {
1551 globfree(&globdata);
1554 if (gr != 0) { /* GLOB_ABORTED ? */
1555 //TODO: testcase for bad glob pattern behavior
1556 bb_error_msg("glob(3) error %d on '%s'", gr, pattern);
1558 if (globdata.gl_pathv && globdata.gl_pathv[0]) {
1559 char **argv = globdata.gl_pathv;
1560 o->length = pattern - o->data; /* "forget" pattern */
1562 o_addstr_with_NUL(o, *argv);
1563 n = o_save_ptr_helper(o, n);
1569 globfree(&globdata);
1571 debug_print_list("o_glob returning", o, n);
1575 /* If o->o_glob == 1, glob the string so far remembered.
1576 * Otherwise, just finish current list[] and start new */
1577 static int o_save_ptr(o_string *o, int n)
1579 if (o->o_glob) { /* if globbing is requested */
1580 /* If o->has_empty_slot, list[n] was already globbed
1581 * (if it was requested back then when it was filled)
1582 * so don't do that again! */
1583 if (!o->has_empty_slot)
1584 return o_glob(o, n); /* o_save_ptr_helper is inside */
1586 return o_save_ptr_helper(o, n);
1589 /* "Please convert list[n] to real char* ptrs, and NULL terminate it." */
1590 static char **o_finalize_list(o_string *o, int n)
1595 n = o_save_ptr(o, n); /* force growth for list[n] if necessary */
1597 debug_print_list("finalized", o, n);
1598 debug_printf_expand("finalized n:%d\n", n);
1599 list = (char**)o->data;
1600 string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
1604 list[n] = o->data + (int)(ptrdiff_t)list[n] + string_start;
1610 /* Expansion can recurse */
1611 #if ENABLE_HUSH_TICK
1612 static int process_command_subs(o_string *dest, const char *s);
1614 static char *expand_string_to_string(const char *str);
1616 #define parse_stream_dquoted(as_string, dest, input, dquote_end) \
1617 parse_stream_dquoted(dest, input, dquote_end)
1619 static int parse_stream_dquoted(o_string *as_string,
1621 struct in_str *input,
1624 /* expand_strvec_to_strvec() takes a list of strings, expands
1625 * all variable references within and returns a pointer to
1626 * a list of expanded strings, possibly with larger number
1627 * of strings. (Think VAR="a b"; echo $VAR).
1628 * This new list is allocated as a single malloc block.
1629 * NULL-terminated list of char* pointers is at the beginning of it,
1630 * followed by strings themself.
1631 * Caller can deallocate entire list by single free(list). */
1633 /* Store given string, finalizing the word and starting new one whenever
1634 * we encounter IFS char(s). This is used for expanding variable values.
1635 * End-of-string does NOT finalize word: think about 'echo -$VAR-' */
1636 static int expand_on_ifs(o_string *output, int n, const char *str)
1639 int word_len = strcspn(str, G.ifs);
1641 if (output->o_escape || !output->o_glob)
1642 o_addQstr(output, str, word_len);
1643 else /* protect backslashes against globbing up :) */
1644 o_addblock_duplicate_backslash(output, str, word_len);
1647 if (!*str) /* EOL - do not finalize word */
1649 o_addchr(output, '\0');
1650 debug_print_list("expand_on_ifs", output, n);
1651 n = o_save_ptr(output, n);
1652 str += strspn(str, G.ifs); /* skip ifs chars */
1654 debug_print_list("expand_on_ifs[1]", output, n);
1658 /* Expand all variable references in given string, adding words to list[]
1659 * at n, n+1,... positions. Return updated n (so that list[n] is next one
1660 * to be filled). This routine is extremely tricky: has to deal with
1661 * variables/parameters with whitespace, $* and $@, and constructs like
1662 * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
1663 static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
1665 /* or_mask is either 0 (normal case) or 0x80
1666 * (expansion of right-hand side of assignment == 1-element expand.
1667 * It will also do no globbing, and thus we must not backslash-quote!) */
1669 char first_ch, ored_ch;
1677 debug_printf_expand("expand_vars_to_list: arg '%s'\n", arg);
1678 debug_print_list("expand_vars_to_list", output, n);
1679 n = o_save_ptr(output, n);
1680 debug_print_list("expand_vars_to_list[0]", output, n);
1682 while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
1683 #if ENABLE_HUSH_TICK
1684 o_string subst_result = NULL_O_STRING;
1686 #if ENABLE_SH_MATH_SUPPORT
1687 char arith_buf[sizeof(arith_t)*3 + 2];
1689 o_addblock(output, arg, p - arg);
1690 debug_print_list("expand_vars_to_list[1]", output, n);
1692 p = strchr(p, SPECIAL_VAR_SYMBOL);
1694 first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */
1695 /* "$@" is special. Even if quoted, it can still
1696 * expand to nothing (not even an empty string) */
1697 if ((first_ch & 0x7f) != '@')
1698 ored_ch |= first_ch;
1701 switch (first_ch & 0x7f) {
1702 /* Highest bit in first_ch indicates that var is double-quoted */
1704 val = utoa(G.root_pid);
1706 case '!': /* bg pid */
1707 val = G.last_bg_pid ? utoa(G.last_bg_pid) : (char*)"";
1709 case '?': /* exitcode */
1710 val = utoa(G.last_exitcode);
1712 case '#': /* argc */
1713 if (arg[1] != SPECIAL_VAR_SYMBOL)
1714 /* actually, it's a ${#var} */
1716 val = utoa(G.global_argc ? G.global_argc-1 : 0);
1721 if (!G.global_argv[i])
1723 ored_ch |= first_ch; /* do it for "$@" _now_, when we know it's not empty */
1724 if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
1725 smallint sv = output->o_escape;
1726 /* unquoted var's contents should be globbed, so don't escape */
1727 output->o_escape = 0;
1728 while (G.global_argv[i]) {
1729 n = expand_on_ifs(output, n, G.global_argv[i]);
1730 debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
1731 if (G.global_argv[i++][0] && G.global_argv[i]) {
1732 /* this argv[] is not empty and not last:
1733 * put terminating NUL, start new word */
1734 o_addchr(output, '\0');
1735 debug_print_list("expand_vars_to_list[2]", output, n);
1736 n = o_save_ptr(output, n);
1737 debug_print_list("expand_vars_to_list[3]", output, n);
1740 output->o_escape = sv;
1742 /* If or_mask is nonzero, we handle assignment 'a=....$@.....'
1743 * and in this case should treat it like '$*' - see 'else...' below */
1744 if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */
1746 o_addQstr(output, G.global_argv[i], strlen(G.global_argv[i]));
1747 if (++i >= G.global_argc)
1749 o_addchr(output, '\0');
1750 debug_print_list("expand_vars_to_list[4]", output, n);
1751 n = o_save_ptr(output, n);
1753 } else { /* quoted $*: add as one word */
1755 o_addQstr(output, G.global_argv[i], strlen(G.global_argv[i]));
1756 if (!G.global_argv[++i])
1759 o_addchr(output, G.ifs[0]);
1763 case SPECIAL_VAR_SYMBOL: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
1764 /* "Empty variable", used to make "" etc to not disappear */
1768 #if ENABLE_HUSH_TICK
1769 case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
1772 //TODO: can we just stuff it into "output" directly?
1773 debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
1774 process_command_subs(&subst_result, arg);
1775 debug_printf_subst("SUBST RES '%s'\n", subst_result.data);
1776 val = subst_result.data;
1779 #if ENABLE_SH_MATH_SUPPORT
1780 case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */
1781 arith_eval_hooks_t hooks;
1786 arg++; /* skip '+' */
1787 *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
1788 debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
1790 /* Optional: skip expansion if expr is simple ("a + 3", "i++" etc) */
1792 if (strchr(arg, '$') != NULL
1793 #if ENABLE_HUSH_TICK
1794 || strchr(arg, '`') != NULL
1797 /* We need to expand. Example:
1798 * echo $(($a + `echo 1`)) $((1 + $((2)) ))
1800 struct in_str input;
1801 o_string dest = NULL_O_STRING;
1803 setup_string_in_str(&input, arg);
1804 parse_stream_dquoted(NULL, &dest, &input, EOF);
1805 //bb_error_msg("'%s' -> '%s'", arg, dest.data);
1806 exp_str = expand_string_to_string(dest.data);
1807 //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
1808 o_free_unsafe(&dest);
1810 hooks.lookupvar = get_local_var_value;
1811 hooks.setvar = arith_set_local_var;
1812 hooks.endofname = endofname;
1813 res = arith(exp_str ? exp_str : arg, &errcode, &hooks);
1818 case -3: maybe_die("arith", "exponent less than 0"); break;
1819 case -2: maybe_die("arith", "divide by zero"); break;
1820 case -5: maybe_die("arith", "expression recursion loop detected"); break;
1821 default: maybe_die("arith", "syntax error"); break;
1824 debug_printf_subst("ARITH RES '"arith_t_fmt"'\n", res);
1825 sprintf(arith_buf, arith_t_fmt, res);
1830 default: /* <SPECIAL_VAR_SYMBOL>varname<SPECIAL_VAR_SYMBOL> */
1832 bool exp_len = false;
1833 bool exp_null = false;
1835 char exp_save = exp_save; /* for compiler */
1836 char exp_op = exp_op; /* for compiler */
1837 char *exp_word = exp_word; /* for compiler */
1841 arg[0] = first_ch & 0x7f;
1843 /* prepare for expansions */
1844 if (var[0] == '#') {
1845 /* handle length expansion ${#var} */
1849 /* maybe handle parameter expansion */
1850 exp_off = strcspn(var, ":-=+?%#");
1854 exp_save = var[exp_off];
1855 exp_null = exp_save == ':';
1856 exp_word = var + exp_off;
1857 if (exp_null) ++exp_word;
1858 exp_op = *exp_word++;
1859 var[exp_off] = '\0';
1863 /* lookup the variable in question */
1864 if (isdigit(var[0])) {
1865 /* handle_dollar() should have vetted var for us */
1867 if (i < G.global_argc)
1868 val = G.global_argv[i];
1869 /* else val remains NULL: $N with too big N */
1871 val = get_local_var_value(var);
1873 /* handle any expansions */
1875 debug_printf_expand("expand: length of '%s' = ", val);
1876 val = utoa(val ? strlen(val) : 0);
1877 debug_printf_expand("%s\n", val);
1878 } else if (exp_off) {
1879 if (exp_op == '%' || exp_op == '#') {
1880 /* we need to do a pattern match */
1883 scan_t scan = pick_scan(exp_op, *exp_word, &zero);
1884 if (exp_op == *exp_word) /* ## or %% */
1886 val = dyn_val = xstrdup(val);
1887 loc = scan(dyn_val, exp_word, zero);
1893 /* we need to do an expansion */
1894 int exp_test = (!val || (exp_null && !val[0]));
1896 exp_test = !exp_test;
1897 debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
1898 exp_null ? "true" : "false", exp_test);
1901 maybe_die(var, *exp_word ? exp_word : "parameter null or not set");
1905 if (exp_op == '=') {
1906 if (isdigit(var[0]) || var[0] == '#') {
1907 maybe_die(var, "special vars cannot assign in this way");
1910 char *new_var = xmalloc(strlen(var) + strlen(val) + 2);
1911 sprintf(new_var, "%s=%s", var, val);
1912 set_local_var(new_var, -1, 0);
1918 var[exp_off] = exp_save;
1922 #if ENABLE_HUSH_TICK
1925 if (!(first_ch & 0x80)) { /* unquoted $VAR */
1926 debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val, output->o_escape);
1928 /* unquoted var's contents should be globbed, so don't escape */
1929 smallint sv = output->o_escape;
1930 output->o_escape = 0;
1931 n = expand_on_ifs(output, n, val);
1933 output->o_escape = sv;
1935 } else { /* quoted $VAR, val will be appended below */
1936 debug_printf_expand("quoted '%s', output->o_escape:%d\n", val, output->o_escape);
1939 } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
1941 o_addQstr(output, val, strlen(val));
1945 /* Do the check to avoid writing to a const string */
1946 if (*p != SPECIAL_VAR_SYMBOL)
1947 *p = SPECIAL_VAR_SYMBOL;
1949 #if ENABLE_HUSH_TICK
1950 o_free(&subst_result);
1953 } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
1956 debug_print_list("expand_vars_to_list[a]", output, n);
1957 /* this part is literal, and it was already pre-quoted
1958 * if needed (much earlier), do not use o_addQstr here! */
1959 o_addstr_with_NUL(output, arg);
1960 debug_print_list("expand_vars_to_list[b]", output, n);
1961 } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
1962 && !(ored_ch & 0x80) /* and all vars were not quoted. */
1965 /* allow to reuse list[n] later without re-growth */
1966 output->has_empty_slot = 1;
1968 o_addchr(output, '\0');
1973 static char **expand_variables(char **argv, int or_mask)
1978 o_string output = NULL_O_STRING;
1980 if (or_mask & 0x100) {
1981 output.o_escape = 1; /* protect against globbing for "$var" */
1982 /* (unquoted $var will temporarily switch it off) */
1989 n = expand_vars_to_list(&output, n, *v, (char)or_mask);
1992 debug_print_list("expand_variables", &output, n);
1994 /* output.data (malloced in one block) gets returned in "list" */
1995 list = o_finalize_list(&output, n);
1996 debug_print_strings("expand_variables[1]", list);
2000 static char **expand_strvec_to_strvec(char **argv)
2002 return expand_variables(argv, 0x100);
2005 /* Used for expansion of right hand of assignments */
2006 /* NB: should NOT do globbing! "export v=/bin/c*; env | grep ^v=" outputs
2008 static char *expand_string_to_string(const char *str)
2010 char *argv[2], **list;
2012 argv[0] = (char*)str;
2014 list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */
2016 if (!list[0] || list[1])
2017 bb_error_msg_and_die("BUG in varexp2");
2018 /* actually, just move string 2*sizeof(char*) bytes back */
2019 overlapping_strcpy((char*)list, list[0]);
2020 debug_printf_expand("string_to_string='%s'\n", (char*)list);
2024 /* Used for "eval" builtin */
2025 static char* expand_strvec_to_string(char **argv)
2029 list = expand_variables(argv, 0x80);
2030 /* Convert all NULs to spaces */
2035 if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
2036 bb_error_msg_and_die("BUG in varexp3");
2037 list[n][-1] = ' '; /* TODO: or to G.ifs[0]? */
2041 overlapping_strcpy((char*)list, list[0]);
2042 debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
2046 static char **expand_assignments(char **argv, int count)
2050 /* Expand assignments into one string each */
2051 for (i = 0; i < count; i++) {
2052 p = add_string_to_strings(p, expand_string_to_string(argv[i]));
2059 void re_execute_shell(const char *s, int is_heredoc); /* never called */
2060 #define clean_up_after_re_execute() ((void)0)
2061 static void reset_traps_to_defaults(void)
2069 for (sig = 0; sig < NSIG; sig++) {
2073 G.traps[sig] = NULL;
2074 /* There is no signal for 0 (EXIT) */
2077 /* there was a trap handler, we are removing it
2078 * (if sig has non-DFL handling,
2079 * we don't need to do anything) */
2080 if (sig < 32 && (G.non_DFL_mask & (1 << sig)))
2082 sigdelset(&G.blocked_set, sig);
2086 sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
2091 static void re_execute_shell(const char *s, int is_heredoc) NORETURN;
2092 static void re_execute_shell(const char *s, int is_heredoc)
2094 char param_buf[sizeof("-$%x:%x:%x:%x") + sizeof(unsigned) * 4];
2095 struct variable *cur;
2096 char **argv, **pp, **pp2;
2099 sprintf(param_buf, "-$%x:%x:%x" USE_HUSH_LOOPS(":%x")
2100 , (unsigned) G.root_pid
2101 , (unsigned) G.last_bg_pid
2102 , (unsigned) G.last_exitcode
2103 USE_HUSH_LOOPS(, G.depth_of_loop)
2105 /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<depth> <vars...>
2106 * 3:-c 4:<cmd> <argN...> 5:NULL
2108 cnt = 5 + G.global_argc;
2109 for (cur = G.top_var; cur; cur = cur->next) {
2110 if (!cur->flg_export || cur->flg_read_only)
2113 G.argv_from_re_execing = pp = xzalloc(sizeof(argv[0]) * cnt);
2114 *pp++ = (char *) G.argv0_for_re_execing;
2116 for (cur = G.top_var; cur; cur = cur->next) {
2117 if (cur->varstr == hush_version_str)
2119 if (cur->flg_read_only) {
2120 *pp++ = (char *) "-R";
2121 *pp++ = cur->varstr;
2122 } else if (!cur->flg_export) {
2123 *pp++ = (char *) "-V";
2124 *pp++ = cur->varstr;
2127 //TODO: pass functions
2128 /* We can pass activated traps here. Say, -Tnn:trap_string
2130 * However, POSIX says that subshells reset signals with traps
2132 * I tested bash-3.2 and it not only does that with true subshells
2133 * of the form ( list ), but with any forked children shells.
2134 * I set trap "echo W" WINCH; and then tried:
2136 * { echo 1; sleep 20; echo 2; } &
2137 * while true; do echo 1; sleep 20; echo 2; break; done &
2138 * true | { echo 1; sleep 20; echo 2; } | cat
2140 * In all these cases sending SIGWINCH to the child shell
2141 * did not run the trap. If I add trap "echo V" WINCH;
2142 * _inside_ group (just before echo 1), it works.
2144 * I conclude it means we don't need to pass active traps here.
2145 * exec syscall below resets them to SIG_DFL for us.
2147 *pp++ = (char *) (is_heredoc ? "-<" : "-c");
2149 pp2 = G.global_argv;
2152 /* *pp = NULL; - is already there */
2154 debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
2155 sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
2156 execv(bb_busybox_exec_path, G.argv_from_re_execing);
2157 /* Fallback. Useful for init=/bin/hush usage etc */
2158 if (G.argv0_for_re_execing[0] == '/')
2159 execv(G.argv0_for_re_execing, G.argv_from_re_execing);
2160 xfunc_error_retval = 127;
2161 bb_error_msg_and_die("can't re-execute the shell");
2164 static void clean_up_after_re_execute(void)
2166 char **pp = G.argv_from_re_execing;
2168 /* Must match re_execute_shell's allocations (if any) */
2170 G.argv_from_re_execing = NULL;
2173 #endif /* !BB_MMU */
2176 static void setup_heredoc(int fd, const char *heredoc)
2178 struct fd_pair pair;
2183 xmove_fd(pair.rd, fd);
2185 len = strlen(heredoc);
2186 /* Try writing without forking. Newer kernels have
2187 * dynamically growing pipes. Must use non-blocking write! */
2190 written = write(pair.wr, heredoc, len);
2200 ndelay_off(pair.wr);
2202 /* Okay, pipe buffer was not big enough */
2203 /* Note: we must not create a stray child (bastard? :)
2204 * for the unsuspecting parent process. We create a grandchild
2205 * and exit before we exec the process which consumes heredoc
2206 * (that exec happens after we return from this function) */
2209 bb_perror_msg_and_die("vfork");
2212 pid = BB_MMU ? fork() : vfork();
2214 bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork");
2218 close(fd); /* read side of the pipe */
2220 full_write(pair.wr, heredoc, len);
2223 /* Delegate blocking writes to another process */
2224 # if ENABLE_HUSH_JOB
2225 die_sleep = 0; /* do not restore tty pgrp on xfunc death */
2227 xmove_fd(pair.wr, STDOUT_FILENO);
2228 re_execute_shell(heredoc, 1);
2233 die_sleep = -1; /* restore tty pgrp on xfunc death */
2235 clean_up_after_re_execute();
2237 wait(NULL); /* wiat till child has died */
2240 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
2241 * and stderr if they are redirected. */
2242 static int setup_redirects(struct command *prog, int squirrel[])
2244 //TODO: no callers ever check return value - ?!
2246 struct redir_struct *redir;
2248 for (redir = prog->redirects; redir; redir = redir->next) {
2249 if (redir->rd_type == REDIRECT_HEREDOC2) {
2250 if (squirrel && redir->fd < 3) {
2251 squirrel[redir->fd] = dup(redir->fd);
2253 /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
2255 debug_printf_parse("set heredoc '%s'\n",
2256 redir->rd_filename);
2257 setup_heredoc(redir->fd, redir->rd_filename);
2261 if (redir->dup == -1) {
2263 if (redir->rd_filename == NULL) {
2264 /* Something went wrong in the parse.
2265 * Pretend it didn't happen */
2268 mode = redir_table[redir->rd_type].mode;
2269 //TODO: check redir for names like '\\'
2270 p = expand_string_to_string(redir->rd_filename);
2271 openfd = open_or_warn(p, mode);
2274 /* this could get lost if stderr has been redirected, but
2275 * bash and ash both lose it as well (though zsh doesn't!) */
2276 //what the above comment tries to say?
2280 openfd = redir->dup;
2283 if (openfd != redir->fd) {
2284 if (squirrel && redir->fd < 3) {
2285 squirrel[redir->fd] = dup(redir->fd);
2288 /* "-" means "close me" and we use -3 for that */
2291 dup2(openfd, redir->fd);
2292 if (redir->dup == -1)
2300 static void restore_redirects(int squirrel[])
2303 for (i = 0; i < 3; i++) {
2306 /* We simply die on error */
2314 #define free_pipe_list(head, indent) free_pipe_list(head)
2315 #define free_pipe(pi, indent) free_pipe(pi)
2317 static void free_pipe_list(struct pipe *head, int indent);
2319 /* Return code is the exit status of the pipe */
2320 static void free_pipe(struct pipe *pi, int indent)
2323 struct command *command;
2324 struct redir_struct *r, *rnext;
2327 if (pi->stopped_cmds > 0) /* why? */
2329 debug_printf_clean("%s run pipe: (pid %d)\n", indenter(indent), getpid());
2330 for (i = 0; i < pi->num_cmds; i++) {
2331 command = &pi->cmds[i];
2332 debug_printf_clean("%s command %d:\n", indenter(indent), i);
2333 if (command->argv) {
2334 for (a = 0, p = command->argv; *p; a++, p++) {
2335 debug_printf_clean("%s argv[%d] = %s\n", indenter(indent), a, *p);
2337 free_strings(command->argv);
2338 command->argv = NULL;
2340 /* not "else if": on syntax error, we may have both! */
2341 if (command->group) {
2342 debug_printf_clean("%s begin group (grp_type:%d)\n", indenter(indent), command->grp_type);
2343 free_pipe_list(command->group, indent+3);
2344 debug_printf_clean("%s end group\n", indenter(indent));
2345 command->group = NULL;
2348 free(command->group_as_string);
2349 command->group_as_string = NULL;
2351 for (r = command->redirects; r; r = rnext) {
2352 debug_printf_clean("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->rd_type].descrip);
2354 /* guard against the case >$FOO, where foo is unset or blank */
2355 if (r->rd_filename) {
2356 debug_printf_clean(" %s\n", r->rd_filename);
2357 free(r->rd_filename);
2358 r->rd_filename = NULL;
2361 debug_printf_clean("&%d\n", r->dup);
2366 command->redirects = NULL;
2368 free(pi->cmds); /* children are an array, they get freed all at once */
2376 static void free_pipe_list(struct pipe *head, int indent)
2378 struct pipe *pi, *next;
2380 for (pi = head; pi; pi = next) {
2382 debug_printf_clean("%s pipe reserved word %d\n", indenter(indent), pi->res_word);
2384 free_pipe(pi, indent);
2385 debug_printf_clean("%s pipe followup code %d\n", indenter(indent), pi->followup);
2387 /*pi->next = NULL;*/
2394 typedef struct nommu_save_t {
2400 #define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
2401 pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
2402 #define pseudo_exec(nommu_save, command, argv_expanded) \
2403 pseudo_exec(command, argv_expanded)
2406 /* Called after [v]fork() in run_pipe, or from builtin_exec.
2408 * XXX no exit() here. If you don't exec, use _exit instead.
2409 * The at_exit handlers apparently confuse the calling process,
2410 * in particular stdin handling. Not sure why? -- because of vfork! (vda) */
2411 static void pseudo_exec_argv(nommu_save_t *nommu_save,
2412 char **argv, int assignment_cnt,
2413 char **argv_expanded) NORETURN;
2414 static void pseudo_exec_argv(nommu_save_t *nommu_save,
2415 char **argv, int assignment_cnt,
2416 char **argv_expanded)
2420 /* Case when we are here: ... | var=val | ... */
2421 if (!argv[assignment_cnt])
2422 _exit(EXIT_SUCCESS);
2424 new_env = expand_assignments(argv, assignment_cnt);
2426 putenv_all(new_env);
2427 free(new_env); /* optional */
2429 nommu_save->new_env = new_env;
2430 nommu_save->old_env = putenv_all_and_save_old(new_env);
2432 if (argv_expanded) {
2433 argv = argv_expanded;
2435 argv = expand_strvec_to_strvec(argv + assignment_cnt);
2437 nommu_save->argv = argv;
2441 /* On NOMMU, we must never block!
2442 * Example: { sleep 99999 | read line } & echo Ok
2443 * read builtin will block on read syscall, leaving parent blocked
2444 * in vfork. Therefore we can't do this:
2447 /* Check if the command matches any of the builtins.
2448 * Depending on context, this might be redundant. But it's
2449 * easier to waste a few CPU cycles than it is to figure out
2450 * if this is one of those cases.
2454 const struct built_in_command *x;
2455 for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) {
2456 if (strcmp(argv[0], x->cmd) == 0) {
2457 debug_printf_exec("running builtin '%s'\n",
2459 rcode = x->function(argv);
2467 #if ENABLE_FEATURE_SH_STANDALONE
2468 /* Check if the command matches any busybox applets */
2469 if (strchr(argv[0], '/') == NULL) {
2470 int a = find_applet_by_name(argv[0]);
2472 #if BB_MMU /* see above why on NOMMU it is not allowed */
2473 if (APPLET_IS_NOEXEC(a)) {
2474 debug_printf_exec("running applet '%s'\n", argv[0]);
2475 run_applet_no_and_exit(a, argv);
2478 /* Re-exec ourselves */
2479 debug_printf_exec("re-execing applet '%s'\n", argv[0]);
2480 sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
2481 execv(bb_busybox_exec_path, argv);
2482 /* If they called chroot or otherwise made the binary no longer
2483 * executable, fall through */
2488 debug_printf_exec("execing '%s'\n", argv[0]);
2489 sigprocmask(SIG_SETMASK, &G.inherited_set, NULL);
2490 execvp(argv[0], argv);
2491 bb_perror_msg("can't exec '%s'", argv[0]);
2492 _exit(EXIT_FAILURE);
2495 static int run_list(struct pipe *pi);
2497 /* Called after [v]fork() in run_pipe
2499 static void pseudo_exec(nommu_save_t *nommu_save,
2500 struct command *command,
2501 char **argv_expanded) NORETURN;
2502 static void pseudo_exec(nommu_save_t *nommu_save,
2503 struct command *command,
2504 char **argv_expanded)
2506 if (command->argv) {
2507 pseudo_exec_argv(nommu_save, command->argv,
2508 command->assignment_cnt, argv_expanded);
2511 if (command->group) {
2512 /* Cases when we are here:
2515 * ... | ( list ) | ...
2516 * ... | { list } | ...
2520 debug_printf_exec("pseudo_exec: run_list\n");
2521 reset_traps_to_defaults();
2522 rcode = run_list(command->group);
2523 /* OK to leak memory by not calling free_pipe_list,
2524 * since this process is about to exit */
2527 re_execute_shell(command->group_as_string, 0);
2531 /* Case when we are here: ... | >file */
2532 debug_printf_exec("pseudo_exec'ed null command\n");
2533 _exit(EXIT_SUCCESS);
2537 static const char *get_cmdtext(struct pipe *pi)
2543 /* This is subtle. ->cmdtext is created only on first backgrounding.
2544 * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
2545 * On subsequent bg argv is trashed, but we won't use it */
2548 argv = pi->cmds[0].argv;
2549 if (!argv || !argv[0]) {
2550 pi->cmdtext = xzalloc(1);
2555 do len += strlen(*argv) + 1; while (*++argv);
2556 pi->cmdtext = p = xmalloc(len);
2557 argv = pi->cmds[0].argv;
2559 len = strlen(*argv);
2560 memcpy(p, *argv, len);
2568 static void insert_bg_job(struct pipe *pi)
2570 struct pipe *thejob;
2573 /* Linear search for the ID of the job to use */
2575 for (thejob = G.job_list; thejob; thejob = thejob->next)
2576 if (thejob->jobid >= pi->jobid)
2577 pi->jobid = thejob->jobid + 1;
2579 /* Add thejob to the list of running jobs */
2581 thejob = G.job_list = xmalloc(sizeof(*thejob));
2583 for (thejob = G.job_list; thejob->next; thejob = thejob->next)
2585 thejob->next = xmalloc(sizeof(*thejob));
2586 thejob = thejob->next;
2589 /* Physically copy the struct job */
2590 memcpy(thejob, pi, sizeof(struct pipe));
2591 thejob->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds);
2592 /* We cannot copy entire pi->cmds[] vector! Double free()s will happen */
2593 for (i = 0; i < pi->num_cmds; i++) {
2594 // TODO: do we really need to have so many fields which are just dead weight
2595 // at execution stage?
2596 thejob->cmds[i].pid = pi->cmds[i].pid;
2597 /* all other fields are not used and stay zero */
2599 thejob->next = NULL;
2600 thejob->cmdtext = xstrdup(get_cmdtext(pi));
2602 /* We don't wait for background thejobs to return -- append it
2603 to the list of backgrounded thejobs and leave it alone */
2604 if (G_interactive_fd)
2605 printf("[%d] %d %s\n", thejob->jobid, thejob->cmds[0].pid, thejob->cmdtext);
2606 G.last_bg_pid = thejob->cmds[0].pid;
2607 G.last_jobid = thejob->jobid;
2610 static void remove_bg_job(struct pipe *pi)
2612 struct pipe *prev_pipe;
2614 if (pi == G.job_list) {
2615 G.job_list = pi->next;
2617 prev_pipe = G.job_list;
2618 while (prev_pipe->next != pi)
2619 prev_pipe = prev_pipe->next;
2620 prev_pipe->next = pi->next;
2623 G.last_jobid = G.job_list->jobid;
2628 /* Remove a backgrounded job */
2629 static void delete_finished_bg_job(struct pipe *pi)
2632 pi->stopped_cmds = 0;
2638 /* Check to see if any processes have exited -- if they
2639 * have, figure out why and see if a job has completed */
2640 static int checkjobs(struct pipe* fg_pipe)
2650 debug_printf_jobs("checkjobs %p\n", fg_pipe);
2653 // if (G.handled_SIGCHLD == G.count_SIGCHLD)
2654 // /* avoid doing syscall, nothing there anyway */
2657 attributes = WUNTRACED;
2658 if (fg_pipe == NULL)
2659 attributes |= WNOHANG;
2661 /* Do we do this right?
2662 * bash-3.00# sleep 20 | false
2664 * [3]+ Stopped sleep 20 | false
2665 * bash-3.00# echo $?
2666 * 1 <========== bg pipe is not fully done, but exitcode is already known!
2669 //FIXME: non-interactive bash does not continue even if all processes in fg pipe
2670 //are stopped. Testcase: "cat | cat" in a script (not on command line)
2671 // + killall -STOP cat
2678 // i = G.count_SIGCHLD;
2679 childpid = waitpid(-1, &status, attributes);
2680 if (childpid <= 0) {
2681 if (childpid && errno != ECHILD)
2682 bb_perror_msg("waitpid");
2683 // else /* Until next SIGCHLD, waitpid's are useless */
2684 // G.handled_SIGCHLD = i;
2687 dead = WIFEXITED(status) || WIFSIGNALED(status);
2690 if (WIFSTOPPED(status))
2691 debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
2692 childpid, WSTOPSIG(status), WEXITSTATUS(status));
2693 if (WIFSIGNALED(status))
2694 debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
2695 childpid, WTERMSIG(status), WEXITSTATUS(status));
2696 if (WIFEXITED(status))
2697 debug_printf_jobs("pid %d exited, exitcode %d\n",
2698 childpid, WEXITSTATUS(status));
2700 /* Were we asked to wait for fg pipe? */
2702 for (i = 0; i < fg_pipe->num_cmds; i++) {
2703 debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid);
2704 if (fg_pipe->cmds[i].pid != childpid)
2706 /* printf("process %d exit %d\n", i, WEXITSTATUS(status)); */
2708 fg_pipe->cmds[i].pid = 0;
2709 fg_pipe->alive_cmds--;
2710 if (i == fg_pipe->num_cmds - 1) {
2711 /* last process gives overall exitstatus */
2712 rcode = WEXITSTATUS(status);
2713 IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;)
2716 fg_pipe->cmds[i].is_stopped = 1;
2717 fg_pipe->stopped_cmds++;
2719 debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
2720 fg_pipe->alive_cmds, fg_pipe->stopped_cmds);
2721 if (fg_pipe->alive_cmds - fg_pipe->stopped_cmds <= 0) {
2722 /* All processes in fg pipe have exited/stopped */
2724 if (fg_pipe->alive_cmds)
2725 insert_bg_job(fg_pipe);
2729 /* There are still running processes in the fg pipe */
2730 goto wait_more; /* do waitpid again */
2732 /* it wasnt fg_pipe, look for process in bg pipes */
2736 /* We asked to wait for bg or orphaned children */
2737 /* No need to remember exitcode in this case */
2738 for (pi = G.job_list; pi; pi = pi->next) {
2739 for (i = 0; i < pi->num_cmds; i++) {
2740 if (pi->cmds[i].pid == childpid)
2741 goto found_pi_and_prognum;
2744 /* Happens when shell is used as init process (init=/bin/sh) */
2745 debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
2746 continue; /* do waitpid again */
2748 found_pi_and_prognum:
2751 pi->cmds[i].pid = 0;
2753 if (!pi->alive_cmds) {
2754 if (G_interactive_fd)
2755 printf(JOB_STATUS_FORMAT, pi->jobid,
2756 "Done", pi->cmdtext);
2757 delete_finished_bg_job(pi);
2761 pi->cmds[i].is_stopped = 1;
2765 } /* while (waitpid succeeds)... */
2771 static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
2774 int rcode = checkjobs(fg_pipe);
2775 /* Job finished, move the shell to the foreground */
2776 p = getpgid(0); /* pgid of our process */
2777 debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p);
2778 tcsetpgrp(G_interactive_fd, p);
2783 /* Start all the jobs, but don't wait for anything to finish.
2786 * Return code is normally -1, when the caller has to wait for children
2787 * to finish to determine the exit status of the pipe. If the pipe
2788 * is a simple builtin command, however, the action is done by the
2789 * time run_pipe returns, and the exit code is provided as the
2792 * Returns -1 only if started some children. IOW: we have to
2793 * mask out retvals of builtins etc with 0xff!
2795 * The only case when we do not need to [v]fork is when the pipe
2796 * is single, non-backgrounded, non-subshell command. Examples:
2797 * cmd ; ... { list } ; ...
2798 * cmd && ... { list } && ...
2799 * cmd || ... { list } || ...
2800 * If it is, then we can run cmd as a builtin, NOFORK [do we do this?],
2801 * or (if SH_STANDALONE) an applet, and we can run the { list }
2802 * with run_list(). If it isn't one of these, we fork and exec cmd.
2804 * Cases when we must fork:
2805 * non-single: cmd | cmd
2806 * backgrounded: cmd & { list } &
2807 * subshell: ( list ) [&]
2809 static int run_pipe(struct pipe *pi)
2811 static const char *const null_ptr = NULL;
2814 int pipefds[2]; /* pipefds[0] is for reading */
2815 struct command *command;
2816 char **argv_expanded;
2819 /* it is not always needed, but we aim to smaller code */
2820 int squirrel[] = { -1, -1, -1 };
2823 debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds);
2825 USE_HUSH_JOB(pi->pgrp = -1;)
2826 pi->stopped_cmds = 0;
2827 command = &(pi->cmds[0]);
2828 argv_expanded = NULL;
2830 if (pi->num_cmds != 1
2831 || pi->followup == PIPE_BG
2832 || command->grp_type == GRP_SUBSHELL
2839 debug_printf_exec(": group:%p argv:'%s'\n",
2840 command->group, command->argv ? command->argv[0] : "NONE");
2842 if (command->group) {
2843 #if ENABLE_HUSH_FUNCTIONS
2844 if (command->grp_type == GRP_FUNCTION) {
2845 /* func () { list } */
2846 bb_error_msg("here we ought to remember function definition, and go on");
2847 return EXIT_SUCCESS;
2851 debug_printf("non-subshell group\n");
2852 setup_redirects(command, squirrel);
2853 debug_printf_exec(": run_list\n");
2854 rcode = run_list(command->group) & 0xff;
2855 restore_redirects(squirrel);
2856 debug_printf_exec("run_pipe return %d\n", rcode);
2857 IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
2861 argv = command->argv ? command->argv : (char **) &null_ptr;
2863 const struct built_in_command *x;
2864 char **new_env = NULL;
2865 char **old_env = NULL;
2867 if (argv[command->assignment_cnt] == NULL) {
2868 /* Assignments, but no command */
2869 /* Ensure redirects take effect. Try "a=t >file" */
2870 setup_redirects(command, squirrel);
2871 restore_redirects(squirrel);
2872 /* Set shell variables */
2874 p = expand_string_to_string(*argv);
2875 debug_printf_exec("set shell var:'%s'->'%s'\n",
2877 set_local_var(p, 0, 0);
2880 /* Do we need to flag set_local_var() errors?
2881 * "assignment to readonly var" and "putenv error"
2883 return EXIT_SUCCESS;
2886 /* Expand the rest into (possibly) many strings each */
2887 argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt);
2889 for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) {
2890 if (strcmp(argv_expanded[0], x->cmd) != 0)
2892 if (x->function == builtin_exec && argv_expanded[1] == NULL) {
2893 debug_printf("exec with redirects only\n");
2894 setup_redirects(command, NULL);
2895 rcode = EXIT_SUCCESS;
2896 goto clean_up_and_ret1;
2898 debug_printf("builtin inline %s\n", argv_expanded[0]);
2899 /* XXX setup_redirects acts on file descriptors, not FILEs.
2900 * This is perfect for work that comes after exec().
2901 * Is it really safe for inline use? Experimentally,
2902 * things seem to work with glibc. */
2903 setup_redirects(command, squirrel);
2904 new_env = expand_assignments(argv, command->assignment_cnt);
2905 old_env = putenv_all_and_save_old(new_env);
2906 debug_printf_exec(": builtin '%s' '%s'...\n",
2907 x->cmd, argv_expanded[1]);
2908 rcode = x->function(argv_expanded) & 0xff;
2909 #if ENABLE_FEATURE_SH_STANDALONE
2912 restore_redirects(squirrel);
2913 free_strings_and_unsetenv(new_env, 1);
2914 putenv_all(old_env);
2915 free(old_env); /* not free_strings()! */
2917 free(argv_expanded);
2918 IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
2919 debug_printf_exec("run_pipe return %d\n", rcode);
2922 #if ENABLE_FEATURE_SH_STANDALONE
2923 i = find_applet_by_name(argv_expanded[0]);
2924 if (i >= 0 && APPLET_IS_NOFORK(i)) {
2925 setup_redirects(command, squirrel);
2926 save_nofork_data(&G.nofork_save);
2927 new_env = expand_assignments(argv, command->assignment_cnt);
2928 old_env = putenv_all_and_save_old(new_env);
2929 debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
2930 argv_expanded[0], argv_expanded[1]);
2931 rcode = run_nofork_applet_prime(&G.nofork_save, i, argv_expanded);
2932 goto clean_up_and_ret;
2935 /* It is neither builtin nor applet. We must fork. */
2939 /* NB: argv_expanded may already be created, and that
2940 * might include `cmd` runs! Do not rerun it! We *must*
2941 * use argv_expanded if it's non-NULL */
2943 /* Going to fork a child per each pipe member */
2947 for (i = 0; i < pi->num_cmds; i++) {
2949 volatile nommu_save_t nommu_save;
2950 nommu_save.new_env = NULL;
2951 nommu_save.old_env = NULL;
2952 nommu_save.argv = NULL;
2954 command = &(pi->cmds[i]);
2955 if (command->argv) {
2956 debug_printf_exec(": pipe member '%s' '%s'...\n",
2957 command->argv[0], command->argv[1]);
2959 debug_printf_exec(": pipe member with no argv\n");
2962 /* pipes are inserted between pairs of commands */
2965 if ((i + 1) < pi->num_cmds)
2968 command->pid = BB_MMU ? fork() : vfork();
2969 if (!command->pid) { /* child */
2971 die_sleep = 0; /* do not restore tty pgrp on xfunc death */
2973 /* Every child adds itself to new process group
2974 * with pgid == pid_of_first_child_in_pipe */
2975 if (G.run_list_level == 1 && G_interactive_fd) {
2978 if (pgrp < 0) /* true for 1st process only */
2980 if (setpgid(0, pgrp) == 0 && pi->followup != PIPE_BG) {
2981 /* We do it in *every* child, not just first,
2983 tcsetpgrp(G_interactive_fd, pgrp);
2987 xmove_fd(nextin, 0);
2988 xmove_fd(pipefds[1], 1); /* write end */
2990 close(pipefds[0]); /* read end */
2991 /* Like bash, explicit redirects override pipes,
2992 * and the pipe fd is available for dup'ing. */
2993 setup_redirects(command, NULL);
2995 /* Restore default handlers just prior to exec */
2996 /*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */
2998 /* Stores to nommu_save list of env vars putenv'ed
2999 * (NOMMU, on MMU we don't need that) */
3000 /* cast away volatility... */
3001 pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded);
3002 /* pseudo_exec() does not return */
3005 /* parent or error */
3007 die_sleep = -1; /* restore tty pgrp on xfunc death */
3010 /* Clean up after vforked child */
3011 clean_up_after_re_execute();
3012 free(nommu_save.argv);
3013 free_strings_and_unsetenv(nommu_save.new_env, 1);
3014 putenv_all(nommu_save.old_env);
3016 free(argv_expanded);
3017 argv_expanded = NULL;
3018 if (command->pid < 0) { /* [v]fork failed */
3019 /* Clearly indicate, was it fork or vfork */
3020 bb_perror_msg(BB_MMU ? "fork" : "vfork");
3024 /* Second and next children need to know pid of first one */
3026 pi->pgrp = command->pid;
3032 if ((i + 1) < pi->num_cmds)
3033 close(pipefds[1]); /* write end */
3034 /* Pass read (output) pipe end to next iteration */
3035 nextin = pipefds[0];
3038 if (!pi->alive_cmds) {
3039 debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
3043 debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds);
3047 #ifndef debug_print_tree
3048 static void debug_print_tree(struct pipe *pi, int lvl)
3050 static const char *const PIPE[] = {
3056 static const char *RES[] = {
3057 [RES_NONE ] = "NONE" ,
3060 [RES_THEN ] = "THEN" ,
3061 [RES_ELIF ] = "ELIF" ,
3062 [RES_ELSE ] = "ELSE" ,
3065 #if ENABLE_HUSH_LOOPS
3066 [RES_FOR ] = "FOR" ,
3067 [RES_WHILE] = "WHILE",
3068 [RES_UNTIL] = "UNTIL",
3070 [RES_DONE ] = "DONE" ,
3072 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
3075 #if ENABLE_HUSH_CASE
3076 [RES_CASE ] = "CASE" ,
3077 [RES_MATCH] = "MATCH",
3078 [RES_CASEI] = "CASEI",
3079 [RES_ESAC ] = "ESAC" ,
3081 [RES_XXXX ] = "XXXX" ,
3082 [RES_SNTX ] = "SNTX" ,
3084 static const char *const GRPTYPE[] = {
3087 #if ENABLE_HUSH_FUNCTIONS
3096 fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "",
3097 pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]);
3099 while (prn < pi->num_cmds) {
3100 struct command *command = &pi->cmds[prn];
3101 char **argv = command->argv;
3103 fprintf(stderr, "%*s cmd %d assignment_cnt:%d",
3105 command->assignment_cnt);
3106 if (command->group) {
3107 fprintf(stderr, " group %s: (argv=%p)\n",
3108 GRPTYPE[command->grp_type],
3110 debug_print_tree(command->group, lvl+1);
3114 if (argv) while (*argv) {
3115 fprintf(stderr, " '%s'", *argv);
3118 fprintf(stderr, "\n");
3127 /* NB: called by pseudo_exec, and therefore must not modify any
3128 * global data until exec/_exit (we can be a child after vfork!) */
3129 static int run_list(struct pipe *pi)
3131 #if ENABLE_HUSH_CASE
3132 char *case_word = NULL;
3134 #if ENABLE_HUSH_LOOPS
3135 struct pipe *loop_top = NULL;
3136 char *for_varname = NULL;
3137 char **for_lcur = NULL;
3138 char **for_list = NULL;
3140 smallint last_followup;
3142 #if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
3143 smalluint cond_code = 0;
3145 enum { cond_code = 0 };
3148 smallint rword; /* enum reserved_style */
3149 smallint last_rword; /* ditto */
3152 debug_printf_exec("run_list start lvl %d\n", G.run_list_level + 1);
3154 #if ENABLE_HUSH_LOOPS
3155 /* Check syntax for "for" */
3156 for (struct pipe *cpipe = pi; cpipe; cpipe = cpipe->next) {
3157 if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN)
3159 /* current word is FOR or IN (BOLD in comments below) */
3160 if (cpipe->next == NULL) {
3161 syntax("malformed for");
3162 debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
3165 /* "FOR v; do ..." and "for v IN a b; do..." are ok */
3166 if (cpipe->next->res_word == RES_DO)
3168 /* next word is not "do". It must be "in" then ("FOR v in ...") */
3169 if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */
3170 || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */
3172 syntax("malformed for");
3173 debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
3179 /* Past this point, all code paths should jump to ret: label
3180 * in order to return, no direct "return" statements please.
3181 * This helps to ensure that no memory is leaked. */
3183 ////TODO: ctrl-Z handling needs re-thinking and re-testing
3186 /* Example of nested list: "while true; do { sleep 1 | exit 2; } done".
3187 * We are saving state before entering outermost list ("while...done")
3188 * so that ctrl-Z will correctly background _entire_ outermost list,
3189 * not just a part of it (like "sleep 1 | exit 2") */
3190 if (++G.run_list_level == 1 && G_interactive_fd) {
3191 if (sigsetjmp(G.toplevel_jb, 1)) {
3192 /* ctrl-Z forked and we are parent; or ctrl-C.
3193 * Sighandler has longjmped us here */
3194 signal(SIGINT, SIG_IGN);
3195 signal(SIGTSTP, SIG_IGN);
3196 /* Restore level (we can be coming from deep inside
3198 G.run_list_level = 1;
3199 #if ENABLE_FEATURE_SH_STANDALONE
3200 if (G.nofork_save.saved) { /* if save area is valid */
3201 debug_printf_jobs("exiting nofork early\n");
3202 restore_nofork_data(&G.nofork_save);
3205 //// if (G.ctrl_z_flag) {
3206 //// /* ctrl-Z has forked and stored pid of the child in pi->pid.
3207 //// * Remember this child as background job */
3208 //// insert_bg_job(pi);
3210 /* ctrl-C. We just stop doing whatever we were doing */
3213 USE_HUSH_LOOPS(loop_top = NULL;)
3214 USE_HUSH_LOOPS(G.depth_of_loop = 0;)
3218 //// /* ctrl-Z handler will store pid etc in pi */
3219 //// G.toplevel_list = pi;
3220 //// G.ctrl_z_flag = 0;
3221 ////#if ENABLE_FEATURE_SH_STANDALONE
3222 //// G.nofork_save.saved = 0; /* in case we will run a nofork later */
3224 //// signal_SA_RESTART_empty_mask(SIGTSTP, handler_ctrl_z);
3225 //// signal(SIGINT, handler_ctrl_c);
3231 last_rword = RES_XXXX;
3233 last_followup = PIPE_SEQ;
3234 rcode = G.last_exitcode;
3236 /* Go through list of pipes, (maybe) executing them. */
3237 for (; pi; pi = USE_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) {
3241 IF_HAS_KEYWORDS(rword = pi->res_word;)
3242 debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
3243 rword, cond_code, last_rword);
3244 #if ENABLE_HUSH_LOOPS
3245 if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR)
3246 && loop_top == NULL /* avoid bumping G.depth_of_loop twice */
3248 /* start of a loop: remember where loop starts */
3253 /* Still in the same "if...", "then..." or "do..." branch? */
3254 if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) {
3255 if ((rcode == 0 && last_followup == PIPE_OR)
3256 || (rcode != 0 && last_followup == PIPE_AND)
3258 /* It is "<true> || CMD" or "<false> && CMD"
3259 * and we should not execute CMD */
3260 debug_printf_exec("skipped cmd because of || or &&\n");
3261 last_followup = pi->followup;
3265 last_followup = pi->followup;
3266 IF_HAS_KEYWORDS(last_rword = rword;)
3269 if (rword == RES_THEN) {
3270 /* if false; then ... fi has exitcode 0! */
3271 G.last_exitcode = rcode = EXIT_SUCCESS;
3272 /* "if <false> THEN cmd": skip cmd */
3276 if (rword == RES_ELSE || rword == RES_ELIF) {
3277 /* "if <true> then ... ELSE/ELIF cmd":
3278 * skip cmd and all following ones */
3283 #if ENABLE_HUSH_LOOPS
3284 if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */
3286 /* first loop through for */
3288 static const char encoded_dollar_at[] ALIGN1 = {
3289 SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0'
3290 }; /* encoded representation of "$@" */
3291 static const char *const encoded_dollar_at_argv[] = {
3292 encoded_dollar_at, NULL
3293 }; /* argv list with one element: "$@" */
3296 vals = (char**)encoded_dollar_at_argv;
3297 if (pi->next->res_word == RES_IN) {
3298 /* if no variable values after "in" we skip "for" */
3299 if (!pi->next->cmds[0].argv) {
3300 G.last_exitcode = rcode = EXIT_SUCCESS;
3301 debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
3304 vals = pi->next->cmds[0].argv;
3305 } /* else: "for var; do..." -> assume "$@" list */
3306 /* create list of variable values */
3307 debug_print_strings("for_list made from", vals);
3308 for_list = expand_strvec_to_strvec(vals);
3309 for_lcur = for_list;
3310 debug_print_strings("for_list", for_list);
3311 for_varname = pi->cmds[0].argv[0];
3312 pi->cmds[0].argv[0] = NULL;
3314 free(pi->cmds[0].argv[0]);
3316 /* "for" loop is over, clean up */
3320 pi->cmds[0].argv[0] = for_varname;
3323 /* Insert next value from for_lcur */
3324 //TODO: does it need escaping?
3325 pi->cmds[0].argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++);
3326 pi->cmds[0].assignment_cnt = 1;
3328 if (rword == RES_IN) {
3329 continue; /* "for v IN list;..." - "in" has no cmds anyway */
3331 if (rword == RES_DONE) {
3332 continue; /* "done" has no cmds too */
3335 #if ENABLE_HUSH_CASE
3336 if (rword == RES_CASE) {
3337 case_word = expand_strvec_to_string(pi->cmds->argv);
3340 if (rword == RES_MATCH) {
3343 if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
3345 /* all prev words didn't match, does this one match? */
3346 argv = pi->cmds->argv;
3348 char *pattern = expand_string_to_string(*argv);
3349 /* TODO: which FNM_xxx flags to use? */
3350 cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0);
3352 if (cond_code == 0) { /* match! we will execute this branch */
3353 free(case_word); /* make future "word)" stop */
3361 if (rword == RES_CASEI) { /* inside of a case branch */
3363 continue; /* not matched yet, skip this pipe */
3366 /* Just pressing <enter> in shell should check for jobs.
3367 * OTOH, in non-interactive shell this is useless
3368 * and only leads to extra job checks */
3369 if (pi->num_cmds == 0) {
3370 if (G_interactive_fd)
3371 goto check_jobs_and_continue;
3375 /* After analyzing all keywords and conditions, we decided
3376 * to execute this pipe. NB: have to do checkjobs(NULL)
3377 * after run_pipe to collect any background children,
3378 * even if list execution is to be stopped. */
3379 debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds);
3382 #if ENABLE_HUSH_LOOPS
3383 G.flag_break_continue = 0;
3385 rcode = r = run_pipe(pi); /* NB: rcode is a smallint */
3387 /* We only ran a builtin: rcode is already known
3388 * and we don't need to wait for anything. */
3389 G.last_exitcode = rcode;
3390 debug_printf_exec(": builtin exitcode %d\n", rcode);
3391 check_and_run_traps(0);
3392 #if ENABLE_HUSH_LOOPS
3393 /* Was it "break" or "continue"? */
3394 if (G.flag_break_continue) {
3395 smallint fbc = G.flag_break_continue;
3396 /* We might fall into outer *loop*,
3397 * don't want to break it too */
3399 G.depth_break_continue--;
3400 if (G.depth_break_continue == 0)
3401 G.flag_break_continue = 0;
3402 /* else: e.g. "continue 2" should *break* once, *then* continue */
3403 } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
3404 if (G.depth_break_continue != 0 || fbc == BC_BREAK)
3405 goto check_jobs_and_break;
3406 /* "continue": simulate end of loop */
3411 } else if (pi->followup == PIPE_BG) {
3412 /* What does bash do with attempts to background builtins? */
3413 /* even bash 3.2 doesn't do that well with nested bg:
3414 * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
3415 * I'm NOT treating inner &'s as jobs */
3416 check_and_run_traps(0);
3418 if (G.run_list_level == 1)
3421 G.last_exitcode = rcode = EXIT_SUCCESS;
3422 debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
3425 if (G.run_list_level == 1 && G_interactive_fd) {
3426 /* Waits for completion, then fg's main shell */
3427 rcode = checkjobs_and_fg_shell(pi);
3428 debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode);
3429 check_and_run_traps(0);
3432 { /* This one just waits for completion */
3433 rcode = checkjobs(pi);
3434 debug_printf_exec(": checkjobs exitcode %d\n", rcode);
3435 check_and_run_traps(0);
3437 G.last_exitcode = rcode;
3441 /* Analyze how result affects subsequent commands */
3443 if (rword == RES_IF || rword == RES_ELIF)
3446 #if ENABLE_HUSH_LOOPS
3447 /* Beware of "while false; true; do ..."! */
3448 if (pi->next && pi->next->res_word == RES_DO) {
3449 if (rword == RES_WHILE) {
3451 /* "while false; do...done" - exitcode 0 */
3452 G.last_exitcode = rcode = EXIT_SUCCESS;
3453 debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
3454 goto check_jobs_and_break;
3457 if (rword == RES_UNTIL) {
3459 debug_printf_exec(": until expr is true: breaking\n");
3460 check_jobs_and_break:
3468 check_jobs_and_continue:
3473 //// if (G.ctrl_z_flag) {
3474 //// /* ctrl-Z forked somewhere in the past, we are the child,
3475 //// * and now we completed running the list. Exit. */
3481 //// if (!G.run_list_level && G_interactive_fd) {
3482 //// signal(SIGTSTP, SIG_IGN);
3483 //// signal(SIGINT, SIG_IGN);
3486 debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode);
3487 #if ENABLE_HUSH_LOOPS
3492 #if ENABLE_HUSH_CASE
3498 /* Select which version we will use */
3499 static int run_and_free_list(struct pipe *pi)
3502 debug_printf_exec("run_and_free_list entered\n");
3504 debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds);
3505 rcode = run_list(pi);
3507 /* free_pipe_list has the side effect of clearing memory.
3508 * In the long run that function can be merged with run_list,
3509 * but doing that now would hobble the debugging effort. */
3510 free_pipe_list(pi, /* indent: */ 0);
3511 debug_printf_exec("run_and_free_list return %d\n", rcode);
3516 static struct pipe *new_pipe(void)
3519 pi = xzalloc(sizeof(struct pipe));
3520 /*pi->followup = 0; - deliberately invalid value */
3521 /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
3525 /* Command (member of a pipe) is complete. The only possible error here
3526 * is out of memory, in which case xmalloc exits. */
3527 static int done_command(struct parse_context *ctx)
3529 /* The command is really already in the pipe structure, so
3530 * advance the pipe counter and make a new, null command. */
3531 struct pipe *pi = ctx->pipe;
3532 struct command *command = ctx->command;
3535 if (command->group == NULL
3536 && command->argv == NULL
3537 && command->redirects == NULL
3539 debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds);
3540 memset(command, 0, sizeof(*command)); /* paranoia */
3541 return pi->num_cmds;
3544 debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds);
3545 //debug_print_tree(ctx->list_head, 20);
3547 debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds);
3550 /* Only real trickiness here is that the uncommitted
3551 * command structure is not counted in pi->num_cmds. */
3552 pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1));
3553 command = &pi->cmds[pi->num_cmds];
3554 memset(command, 0, sizeof(*command));
3556 ctx->command = command;
3557 /* but ctx->pipe and ctx->list_head remain unchanged */
3559 return pi->num_cmds; /* used only for 0/nonzero check */
3562 static void done_pipe(struct parse_context *ctx, pipe_style type)
3566 debug_printf_parse("done_pipe entered, followup %d\n", type);
3567 /* Close previous command */
3568 not_null = done_command(ctx);
3569 ctx->pipe->followup = type;
3571 ctx->pipe->pi_inverted = ctx->ctx_inverted;
3572 ctx->ctx_inverted = 0;
3573 ctx->pipe->res_word = ctx->ctx_res_w;
3576 /* Without this check, even just <enter> on command line generates
3577 * tree of three NOPs (!). Which is harmless but annoying.
3578 * IOW: it is safe to do it unconditionally.
3579 * RES_NONE case is for "for a in; do ..." (empty IN set)
3580 * and other cases to work. */
3583 || ctx->ctx_res_w == RES_FI
3584 || ctx->ctx_res_w == RES_DONE
3585 || ctx->ctx_res_w == RES_FOR
3586 || ctx->ctx_res_w == RES_IN
3587 || ctx->ctx_res_w == RES_ESAC
3591 debug_printf_parse("done_pipe: adding new pipe: "
3592 "not_null:%d ctx->ctx_res_w:%d\n",
3593 not_null, ctx->ctx_res_w);
3595 ctx->pipe->next = new_p;
3597 /* RES_THEN, RES_DO etc are "sticky" -
3598 * they remain set for commands inside if/while.
3599 * This is used to control execution.
3600 * RES_FOR and RES_IN are NOT sticky (needed to support
3601 * cases where variable or value happens to match a keyword):
3603 #if ENABLE_HUSH_LOOPS
3604 if (ctx->ctx_res_w == RES_FOR
3605 || ctx->ctx_res_w == RES_IN)
3606 ctx->ctx_res_w = RES_NONE;
3608 #if ENABLE_HUSH_CASE
3609 if (ctx->ctx_res_w == RES_MATCH)
3610 ctx->ctx_res_w = RES_CASEI;
3612 ctx->command = NULL; /* trick done_command below */
3613 /* Create the memory for command, roughly:
3614 * ctx->pipe->cmds = new struct command;
3615 * ctx->command = &ctx->pipe->cmds[0];
3618 //debug_print_tree(ctx->list_head, 10);
3620 debug_printf_parse("done_pipe return\n");
3623 static void initialize_context(struct parse_context *ctx)
3625 memset(ctx, 0, sizeof(*ctx));
3626 ctx->pipe = ctx->list_head = new_pipe();
3627 /* Create the memory for command, roughly:
3628 * ctx->pipe->cmds = new struct command;
3629 * ctx->command = &ctx->pipe->cmds[0];
3634 /* If a reserved word is found and processed, parse context is modified
3635 * and 1 is returned.
3638 struct reserved_combo {
3641 unsigned char assignment_flag;
3645 FLAG_END = (1 << RES_NONE ),
3647 FLAG_IF = (1 << RES_IF ),
3648 FLAG_THEN = (1 << RES_THEN ),
3649 FLAG_ELIF = (1 << RES_ELIF ),
3650 FLAG_ELSE = (1 << RES_ELSE ),
3651 FLAG_FI = (1 << RES_FI ),
3653 #if ENABLE_HUSH_LOOPS
3654 FLAG_FOR = (1 << RES_FOR ),
3655 FLAG_WHILE = (1 << RES_WHILE),
3656 FLAG_UNTIL = (1 << RES_UNTIL),
3657 FLAG_DO = (1 << RES_DO ),
3658 FLAG_DONE = (1 << RES_DONE ),
3659 FLAG_IN = (1 << RES_IN ),
3661 #if ENABLE_HUSH_CASE
3662 FLAG_MATCH = (1 << RES_MATCH),
3663 FLAG_ESAC = (1 << RES_ESAC ),
3665 FLAG_START = (1 << RES_XXXX ),
3668 static const struct reserved_combo* match_reserved_word(o_string *word)
3670 /* Mostly a list of accepted follow-up reserved words.
3671 * FLAG_END means we are done with the sequence, and are ready
3672 * to turn the compound list into a command.
3673 * FLAG_START means the word must start a new compound list.
3675 static const struct reserved_combo reserved_list[] = {
3677 { "!", RES_NONE, NOT_ASSIGNMENT , 0 },
3678 { "if", RES_IF, WORD_IS_KEYWORD, FLAG_THEN | FLAG_START },
3679 { "then", RES_THEN, WORD_IS_KEYWORD, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
3680 { "elif", RES_ELIF, WORD_IS_KEYWORD, FLAG_THEN },
3681 { "else", RES_ELSE, WORD_IS_KEYWORD, FLAG_FI },
3682 { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
3684 #if ENABLE_HUSH_LOOPS
3685 { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
3686 { "while", RES_WHILE, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
3687 { "until", RES_UNTIL, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
3688 { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
3689 { "do", RES_DO, WORD_IS_KEYWORD, FLAG_DONE },
3690 { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
3692 #if ENABLE_HUSH_CASE
3693 { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
3694 { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
3697 const struct reserved_combo *r;
3699 for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
3700 if (strcmp(word->data, r->literal) == 0)
3705 static int reserved_word(o_string *word, struct parse_context *ctx)
3707 #if ENABLE_HUSH_CASE
3708 static const struct reserved_combo reserved_match = {
3709 "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
3712 const struct reserved_combo *r;
3714 r = match_reserved_word(word);
3718 debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
3719 #if ENABLE_HUSH_CASE
3720 if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE)
3721 /* "case word IN ..." - IN part starts first match part */
3722 r = &reserved_match;
3725 if (r->flag == 0) { /* '!' */
3726 if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
3727 syntax("! ! command");
3728 IF_HAS_KEYWORDS(ctx->ctx_res_w = RES_SNTX;)
3730 ctx->ctx_inverted = 1;
3733 if (r->flag & FLAG_START) {
3734 struct parse_context *old;
3735 old = xmalloc(sizeof(*old));
3736 debug_printf_parse("push stack %p\n", old);
3737 *old = *ctx; /* physical copy */
3738 initialize_context(ctx);
3740 } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) {
3742 ctx->ctx_res_w = RES_SNTX;
3745 ctx->ctx_res_w = r->res;
3746 ctx->old_flag = r->flag;
3747 if (ctx->old_flag & FLAG_END) {
3748 struct parse_context *old;
3749 done_pipe(ctx, PIPE_SEQ);
3750 debug_printf_parse("pop stack %p\n", ctx->stack);
3752 old->command->group = ctx->list_head;
3753 old->command->grp_type = GRP_NORMAL;
3755 o_addstr(&old->as_string, ctx->as_string.data);
3756 o_free_unsafe(&ctx->as_string);
3757 old->command->group_as_string = xstrdup(old->as_string.data);
3758 debug_printf_parse("pop, remembering as:'%s'\n",
3759 old->command->group_as_string);
3761 *ctx = *old; /* physical copy */
3764 word->o_assignment = r->assignment_flag;
3769 /* Word is complete, look at it and update parsing context.
3770 * Normal return is 0. Syntax errors return 1.
3771 * Note: on return, word is reset, but not o_free'd!
3773 static int done_word(o_string *word, struct parse_context *ctx)
3775 struct command *command = ctx->command;
3777 debug_printf_parse("done_word entered: '%s' %p\n", word->data, command);
3778 if (word->length == 0 && word->nonnull == 0) {
3779 debug_printf_parse("done_word return 0: true null, ignored\n");
3782 /* If this word wasn't an assignment, next ones definitely
3783 * can't be assignments. Even if they look like ones. */
3784 if (word->o_assignment != DEFINITELY_ASSIGNMENT
3785 && word->o_assignment != WORD_IS_KEYWORD
3787 word->o_assignment = NOT_ASSIGNMENT;
3789 if (word->o_assignment == DEFINITELY_ASSIGNMENT)
3790 command->assignment_cnt++;
3791 word->o_assignment = MAYBE_ASSIGNMENT;
3794 if (ctx->pending_redirect) {
3795 /* We do not glob in e.g. >*.tmp case. bash seems to glob here
3796 * only if run as "bash", not "sh" */
3797 /* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
3799 * ...the word that follows the redirection operator
3800 * shall be subjected to tilde expansion, parameter expansion,
3801 * command substitution, arithmetic expansion, and quote
3802 * removal. Pathname expansion shall not be performed
3803 * on the word by a non-interactive shell; an interactive
3804 * shell may perform it, but shall do so only when
3805 * the expansion would result in one word."
3807 ctx->pending_redirect->rd_filename = xstrdup(word->data);
3808 word->o_assignment = NOT_ASSIGNMENT;
3809 debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
3811 /* "{ echo foo; } echo bar" - bad */
3812 /* NB: bash allows e.g.:
3813 * if true; then { echo foo; } fi
3814 * while if false; then false; fi do break; done
3816 * while if false; then false; fi; do; break; done
3818 if (command->group) {
3820 debug_printf_parse("done_word return 1: syntax error, "
3821 "groups and arglists don't mix\n");
3825 #if ENABLE_HUSH_CASE
3826 if (ctx->ctx_dsemicolon
3827 && strcmp(word->data, "esac") != 0 /* not "... pattern) cmd;; esac" */
3829 /* already done when ctx_dsemicolon was set to 1: */
3830 /* ctx->ctx_res_w = RES_MATCH; */
3831 ctx->ctx_dsemicolon = 0;
3834 if (!command->argv /* if it's the first word... */
3835 #if ENABLE_HUSH_LOOPS
3836 && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
3837 && ctx->ctx_res_w != RES_IN
3840 debug_printf_parse(": checking '%s' for reserved-ness\n", word->data);
3841 if (reserved_word(word, ctx)) {
3843 debug_printf_parse("done_word return %d\n",
3844 (ctx->ctx_res_w == RES_SNTX));
3845 return (ctx->ctx_res_w == RES_SNTX);
3849 if (word->nonnull /* word had "xx" or 'xx' at least as part of it. */
3850 /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
3851 && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL)
3852 /* (otherwise it's known to be not empty and is already safe) */
3854 /* exclude "$@" - it can expand to no word despite "" */
3855 char *p = word->data;
3856 while (p[0] == SPECIAL_VAR_SYMBOL
3857 && (p[1] & 0x7f) == '@'
3858 && p[2] == SPECIAL_VAR_SYMBOL
3862 if (p == word->data || p[0] != '\0') {
3863 /* saw no "$@", or not only "$@" but some
3864 * real text is there too */
3865 /* insert "empty variable" reference, this makes
3866 * e.g. "", $empty"" etc to not disappear */
3867 o_addchr(word, SPECIAL_VAR_SYMBOL);
3868 o_addchr(word, SPECIAL_VAR_SYMBOL);
3871 command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
3872 debug_print_strings("word appended to argv", command->argv);
3876 ctx->pending_redirect = NULL;
3878 #if ENABLE_HUSH_LOOPS
3879 /* Force FOR to have just one word (variable name) */
3880 /* NB: basically, this makes hush see "for v in ..." syntax as if
3881 * as it is "for v; in ...". FOR and IN become two pipe structs
3883 if (ctx->ctx_res_w == RES_FOR) {
3884 //TODO: check that command->argv[0] is a valid variable name!
3885 done_pipe(ctx, PIPE_SEQ);
3888 #if ENABLE_HUSH_CASE
3889 /* Force CASE to have just one word */
3890 if (ctx->ctx_res_w == RES_CASE) {
3891 done_pipe(ctx, PIPE_SEQ);
3894 debug_printf_parse("done_word return 0\n");
3899 /* Peek ahead in the input to find out if we have a "&n" construct,
3900 * as in "2>&1", that represents duplicating a file descriptor.
3901 * Return: -3 if >&- "close fd" construct is seen,
3902 * -2 (syntax error), -1 if no & was seen, or the number found.
3905 #define redirect_dup_num(as_string, input) \
3906 redirect_dup_num(input)
3908 static int redirect_dup_num(o_string *as_string, struct in_str *input)
3916 ch = i_getch(input); /* get the & */
3918 o_addchr(as_string, ch);
3922 ch = i_getch(input);
3924 o_addchr(as_string, ch);
3926 return -3; /* "-" represents "close me" */
3930 while (ch != EOF && isdigit(ch)) {
3931 d = d*10 + (ch-'0');
3933 ch = i_getch(input);
3935 o_addchr(as_string, ch);
3941 //TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
3943 bb_error_msg("ambiguous redirect");
3947 /* Return code is 0 normally, 1 if a syntax error is detected
3949 static int parse_redirect(struct parse_context *ctx,
3952 struct in_str *input)
3954 struct command *command = ctx->command;
3955 struct redir_struct *redir;
3956 struct redir_struct **redirp;
3960 if (style != REDIRECT_HEREDOC) {
3961 /* Check for a '2>&1' type redirect */
3962 dup_num = redirect_dup_num(&ctx->as_string, input);
3964 return 1; /* syntax error */
3966 //TODO: else { check for <<-word }
3968 if (style == REDIRECT_OVERWRITE && dup_num == -1) {
3969 int ch = i_peek(input);
3971 /* >|FILE redirect ("clobbering" >).
3972 * Since we do not support "set -o noclobber" yet,
3973 * >| and > are the same for now. Just eat |.
3975 ch = i_getch(input);
3977 o_addchr(&ctx->as_string, ch);
3982 /* Create a new redir_struct and append it to the linked list */
3983 redirp = &command->redirects;
3984 while ((redir = *redirp) != NULL) {
3985 redirp = &(redir->next);
3987 *redirp = redir = xzalloc(sizeof(*redir));
3988 /* redir->next = NULL; */
3989 /* redir->rd_filename = NULL; */
3990 redir->rd_type = style;
3991 redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
3993 debug_printf_parse("redirect type %d %s\n", redir->fd, redir_table[style].descrip);
3995 redir->dup = dup_num;
3996 if (dup_num != -1) {
3997 /* Erik had a check here that the file descriptor in question
3998 * is legit; I postpone that to "run time"
3999 * A "-" representation of "close me" shows up as a -3 here */
4000 debug_printf_parse("duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
4002 /* Set ctx->pending_redirect, so we know what to do at the
4003 * end of the next parsed word. */
4004 ctx->pending_redirect = redir;
4009 /* If a redirect is immediately preceded by a number, that number is
4010 * supposed to tell which file descriptor to redirect. This routine
4011 * looks for such preceding numbers. In an ideal world this routine
4012 * needs to handle all the following classes of redirects...
4013 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
4014 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
4015 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
4016 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
4018 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
4020 * ... If n is quoted, the number shall not be recognized as part of
4021 * the redirection expression. For example:
4023 * writes the character 2 into file a"
4024 * I am not sure we do it right (and not sure we care)
4026 * A -1 return means no valid number was found,
4027 * the caller should use the appropriate default for this redirection.
4029 static int redirect_opt_num(o_string *o)
4033 if (o->data == NULL)
4035 num = bb_strtou(o->data, NULL, 10);
4036 if (errno || num < 0)
4042 //TODO: add NOMMU as_string fill
4043 static char *fetch_till_str(struct in_str *input, const char *word)
4045 o_string heredoc = NULL_O_STRING;
4050 ch = i_getch(input);
4052 o_free_unsafe(&heredoc);
4056 if (strcmp(heredoc.data + past_EOL, word) == 0) {
4057 heredoc.data[past_EOL] = '\0';
4058 debug_printf_parse("parsed heredoc '%s'\n", heredoc.data);
4059 return heredoc.data;
4061 past_EOL = heredoc.length + 1;
4063 o_addchr(&heredoc, ch);
4067 static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input)
4069 struct pipe *pi = ctx->list_head;
4073 struct command *cmd = pi->cmds;
4075 debug_printf_parse("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
4077 cmd->argv ? cmd->argv[0] : "NONE");
4078 for (i = 0; i < pi->num_cmds; i++) {
4079 struct redir_struct *redirect = cmd->redirects;
4081 debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
4082 i, cmd->argv ? cmd->argv[0] : "NONE");
4084 if (redirect->rd_type == REDIRECT_HEREDOC) {
4087 if (heredoc_cnt <= 0)
4088 return 1; /* error */
4089 redirect->rd_type = REDIRECT_HEREDOC2;
4090 p = fetch_till_str(input, redirect->rd_filename);
4092 return 1; /* unexpected EOF */
4093 free(redirect->rd_filename);
4094 redirect->rd_filename = p;
4097 redirect = redirect->next;
4103 /* Should be 0. If it isn't, it's a parse error */
4109 #define parse_stream(pstring, input, end_trigger) \
4110 parse_stream(input, end_trigger)
4112 static struct pipe *parse_stream(char **pstring,
4113 struct in_str *input,
4115 static void parse_and_run_string(const char *s);
4117 #if ENABLE_HUSH_TICK
4118 static FILE *generate_stream_from_string(const char *s)
4121 int pid, channel[2];
4124 pid = BB_MMU ? fork() : vfork();
4126 bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork");
4128 if (pid == 0) { /* child */
4130 die_sleep = 0; /* do not restore tty pgrp on xfunc death */
4132 /* Process substitution is not considered to be usual
4133 * 'command execution'.
4134 * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
4141 close(channel[0]); /* NB: close _first_, then move fd! */
4142 xmove_fd(channel[1], 1);
4143 /* Prevent it from trying to handle ctrl-z etc */
4144 USE_HUSH_JOB(G.run_list_level = 1;)
4146 reset_traps_to_defaults();
4147 parse_and_run_string(s);
4148 _exit(G.last_exitcode);
4150 /* We re-execute after vfork on NOMMU. This makes this script safe:
4151 * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
4152 * huge=`cat BIG` # was blocking here forever
4155 re_execute_shell(s, 0);
4161 die_sleep = -1; /* restore tty pgrp on xfunc death */
4163 clean_up_after_re_execute();
4165 pf = fdopen(channel[0], "r");
4169 /* Return code is exit status of the process that is run. */
4170 static int process_command_subs(o_string *dest, const char *s)
4173 struct in_str pipe_str;
4176 pf = generate_stream_from_string(s);
4179 close_on_exec_on(fileno(pf));
4181 /* Now send results of command back into original context */
4182 setup_file_in_str(&pipe_str, pf);
4184 while ((ch = i_getch(&pipe_str)) != EOF) {
4190 o_addchr(dest, '\n');
4193 o_addQchr(dest, ch);
4196 debug_printf("done reading from pipe, pclose()ing\n");
4197 /* Note: we got EOF, and we just close the read end of the pipe.
4198 * We do not wait for the `cmd` child to terminate. bash and ash do.
4200 * echo `echo Hi; exec 1>&-; sleep 2` - bash waits 2 sec
4201 * `false`; echo $? - bash outputs "1"
4204 debug_printf("closed FILE from child. return 0\n");
4209 static int parse_group(o_string *dest, struct parse_context *ctx,
4210 struct in_str *input, int ch)
4212 /* dest contains characters seen prior to ( or {.
4213 * Typically it's empty, but for function defs,
4214 * it contains function name (without '()'). */
4215 struct pipe *pipe_list;
4217 struct command *command = ctx->command;
4219 debug_printf_parse("parse_group entered\n");
4220 #if ENABLE_HUSH_FUNCTIONS
4221 if (ch == 'F') { /* function definition? */
4222 bb_error_msg("aha '%s' is a function, parsing it...", dest->data);
4223 //command->fname = dest->data;
4224 command->grp_type = GRP_FUNCTION;
4225 //TODO: review every o_reset() location... do they handle all o_string fields correctly?
4226 memset(dest, 0, sizeof(*dest));
4229 if (command->argv /* word [word](... */
4230 || dest->length /* word(... */
4231 || dest->nonnull /* ""(... */
4234 debug_printf_parse("parse_group return 1: "
4235 "syntax error, groups and arglists don't mix\n");
4241 command->grp_type = GRP_SUBSHELL;
4245 char *as_string = NULL;
4247 pipe_list = parse_stream(&as_string, input, endch);
4250 o_addstr(&ctx->as_string, as_string);
4252 /* empty ()/{} or parse error? */
4253 if (!pipe_list || pipe_list == ERR_PTR) {
4258 debug_printf_parse("parse_group return 1: "
4259 "parse_stream returned %p\n", pipe_list);
4262 command->group = pipe_list;
4264 as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */
4265 command->group_as_string = as_string;
4266 debug_printf_parse("end of group, remembering as:'%s'\n",
4267 command->group_as_string);
4270 debug_printf_parse("parse_group return 0\n");
4272 /* command remains "open", available for possible redirects */
4275 #if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT
4276 /* Subroutines for copying $(...) and `...` things */
4277 static void add_till_backquote(o_string *dest, struct in_str *input);
4279 static void add_till_single_quote(o_string *dest, struct in_str *input)
4282 int ch = i_getch(input);
4290 /* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
4291 static void add_till_double_quote(o_string *dest, struct in_str *input)
4294 int ch = i_getch(input);
4297 if (ch == '\\') { /* \x. Copy both chars. */
4299 ch = i_getch(input);
4305 add_till_backquote(dest, input);
4309 //if (ch == '$') ...
4312 /* Process `cmd` - copy contents until "`" is seen. Complicated by
4314 * "Within the backquoted style of command substitution, backslash
4315 * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
4316 * The search for the matching backquote shall be satisfied by the first
4317 * backquote found without a preceding backslash; during this search,
4318 * if a non-escaped backquote is encountered within a shell comment,
4319 * a here-document, an embedded command substitution of the $(command)
4320 * form, or a quoted string, undefined results occur. A single-quoted
4321 * or double-quoted string that begins, but does not end, within the
4322 * "`...`" sequence produces undefined results."
4324 * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
4326 static void add_till_backquote(o_string *dest, struct in_str *input)
4329 int ch = i_getch(input);
4332 if (ch == '\\') { /* \x. Copy both chars unless it is \` */
4333 int ch2 = i_getch(input);
4334 if (ch2 != '`' && ch2 != '$' && ch2 != '\\')
4343 /* Process $(cmd) - copy contents until ")" is seen. Complicated by
4344 * quoting and nested ()s.
4345 * "With the $(command) style of command substitution, all characters
4346 * following the open parenthesis to the matching closing parenthesis
4347 * constitute the command. Any valid shell script can be used for command,
4348 * except a script consisting solely of redirections which produces
4349 * unspecified results."
4351 * echo $(echo '(TEST)' BEST) (TEST) BEST
4352 * echo $(echo 'TEST)' BEST) TEST) BEST
4353 * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
4355 static void add_till_closing_paren(o_string *dest, struct in_str *input, bool dbl)
4359 int ch = i_getch(input);
4368 if (i_peek(input) == ')') {
4376 add_till_single_quote(dest, input);
4381 add_till_double_quote(dest, input);
4385 if (ch == '\\') { /* \x. Copy verbatim. Important for \(, \) */
4386 ch = i_getch(input);
4394 #endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT */
4396 /* Return code: 0 for OK, 1 for syntax error */
4398 #define handle_dollar(as_string, dest, input) \
4399 handle_dollar(dest, input)
4401 static int handle_dollar(o_string *as_string,
4403 struct in_str *input)
4406 int ch = i_peek(input); /* first character after the $ */
4407 unsigned char quote_mask = dest->o_escape ? 0x80 : 0;
4409 debug_printf_parse("handle_dollar entered: ch='%c'\n", ch);
4411 ch = i_getch(input);
4413 if (as_string) o_addchr(as_string, ch);
4416 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4418 debug_printf_parse(": '%c'\n", ch);
4419 o_addchr(dest, ch | quote_mask);
4422 if (!isalnum(ch) && ch != '_')
4424 ch = i_getch(input);
4426 if (as_string) o_addchr(as_string, ch);
4429 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4430 } else if (isdigit(ch)) {
4432 ch = i_getch(input);
4434 if (as_string) o_addchr(as_string, ch);
4436 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4437 debug_printf_parse(": '%c'\n", ch);
4438 o_addchr(dest, ch | quote_mask);
4439 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4440 } else switch (ch) {
4442 case '!': /* last bg pid */
4443 case '?': /* last exit code */
4444 case '#': /* number of args */
4445 case '*': /* args */
4446 case '@': /* args */
4447 goto make_one_char_var;
4449 bool first_char, all_digits;
4451 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4452 ch = i_getch(input);
4454 if (as_string) o_addchr(as_string, ch);
4456 /* XXX maybe someone will try to escape the '}' */
4461 ch = i_getch(input);
4463 if (as_string) o_addchr(as_string, ch);
4470 /* ${#var}: length of var contents */
4472 else if (isdigit(ch)) {
4479 && ( (all_digits && !isdigit(ch))
4480 || (!all_digits && !isalnum(ch) && ch != '_')
4483 /* handle parameter expansions
4484 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
4489 case ':': /* null modifier */
4490 if (expansion == 0) {
4491 debug_printf_parse(": null modifier\n");
4496 case '#': /* remove prefix */
4497 case '%': /* remove suffix */
4498 if (expansion == 0) {
4499 debug_printf_parse(": remove suffix/prefix\n");
4504 case '-': /* default value */
4505 case '=': /* assign default */
4506 case '+': /* alternative */
4507 case '?': /* error indicate */
4508 debug_printf_parse(": parameter expansion\n");
4513 syntax("unterminated ${name}");
4514 debug_printf_parse("handle_dollar return 1: unterminated ${name}\n");
4519 debug_printf_parse(": '%c'\n", ch);
4520 o_addchr(dest, ch | quote_mask);
4524 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4527 #if (ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK)
4532 ch = i_getch(input);
4534 if (as_string) o_addchr(as_string, ch);
4536 # if ENABLE_SH_MATH_SUPPORT
4537 if (i_peek(input) == '(') {
4538 ch = i_getch(input);
4540 if (as_string) o_addchr(as_string, ch);
4542 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4543 o_addchr(dest, /*quote_mask |*/ '+');
4547 add_till_closing_paren(dest, input, true);
4550 o_addstr(as_string, dest->data + pos);
4551 o_addchr(as_string, ')');
4552 o_addchr(as_string, ')');
4555 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4559 # if ENABLE_HUSH_TICK
4560 //int pos = dest->length;
4561 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4562 o_addchr(dest, quote_mask | '`');
4566 add_till_closing_paren(dest, input, false);
4569 o_addstr(as_string, dest->data + pos);
4570 o_addchr(as_string, '`');
4573 //debug_printf_subst("SUBST RES2 '%s'\n", dest->data + pos);
4574 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4580 ch = i_getch(input);
4582 if (as_string) o_addchr(as_string, ch);
4585 if (isalnum(ch)) { /* it's $_name or $_123 */
4591 /* $_ Shell or shell script name; or last cmd name */
4592 /* $- Option flags set by set builtin or shell options (-i etc) */
4594 o_addQchr(dest, '$');
4596 debug_printf_parse("handle_dollar return 0\n");
4601 #define parse_stream_dquoted(as_string, dest, input, dquote_end) \
4602 parse_stream_dquoted(dest, input, dquote_end)
4604 static int parse_stream_dquoted(o_string *as_string,
4606 struct in_str *input,
4613 ch = i_getch(input);
4615 if (as_string && ch != EOF) o_addchr(as_string, ch);
4617 if (ch == dquote_end) { /* may be only '"' or EOF */
4619 if (dest->o_assignment == NOT_ASSIGNMENT)
4620 dest->o_escape ^= 1;
4621 debug_printf_parse("parse_stream_dquoted return 0\n");
4625 syntax("unterminated \"");
4626 debug_printf_parse("parse_stream_dquoted return 1: unterminated \"\n");
4631 next = i_peek(input);
4633 debug_printf_parse(": ch=%c (%d) escape=%d\n",
4634 ch, ch, dest->o_escape);
4638 debug_printf_parse("parse_stream_dquoted return 1: \\<eof>\n");
4642 * "The backslash retains its special meaning [in "..."]
4643 * only when followed by one of the following characters:
4644 * $, `, ", \, or <newline>. A double quote may be quoted
4645 * within double quotes by preceding it with a backslash.
4646 * If enabled, history expansion will be performed unless
4647 * an ! appearing in double quotes is escaped using
4648 * a backslash. The backslash preceding the ! is not removed."
4650 if (strchr("$`\"\\", next) != NULL) {
4651 o_addqchr(dest, i_getch(input));
4653 o_addqchr(dest, '\\');
4658 if (handle_dollar(as_string, dest, input) != 0) {
4659 debug_printf_parse("parse_stream_dquoted return 1: "
4660 "handle_dollar returned non-0\n");
4665 #if ENABLE_HUSH_TICK
4667 //int pos = dest->length;
4668 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4669 o_addchr(dest, 0x80 | '`');
4670 add_till_backquote(dest, input);
4671 o_addchr(dest, SPECIAL_VAR_SYMBOL);
4672 //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
4676 o_addQchr(dest, ch);
4678 && (dest->o_assignment == MAYBE_ASSIGNMENT
4679 || dest->o_assignment == WORD_IS_KEYWORD)
4680 && is_assignment(dest->data)
4682 dest->o_assignment = DEFINITELY_ASSIGNMENT;
4688 * Scan input until EOF or end_trigger char.
4689 * Return a list of pipes to execute, or NULL on EOF
4690 * or if end_trigger character is met.
4691 * On syntax error, exit is shell is not interactive,
4692 * reset parsing machinery and start parsing anew,
4693 * or return ERR_PTR.
4695 static struct pipe *parse_stream(char **pstring,
4696 struct in_str *input,
4699 struct parse_context ctx;
4700 o_string dest = NULL_O_STRING;
4704 /* Double-quote state is handled in the state variable is_in_dquote.
4705 * A single-quote triggers a bypass of the main loop until its mate is
4706 * found. When recursing, quote state is passed in via dest->o_escape.
4708 debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
4709 end_trigger ? : 'X');
4711 G.ifs = get_local_var_value("IFS");
4716 #if ENABLE_HUSH_INTERACTIVE
4717 input->promptmode = 0; /* PS1 */
4719 /* dest.o_assignment = MAYBE_ASSIGNMENT; - already is */
4720 initialize_context(&ctx);
4725 const char *is_special;
4729 redir_type redir_style;
4732 if (parse_stream_dquoted(&ctx.as_string, &dest, input, '"')) {
4735 /* We reached closing '"' */
4738 ch = i_getch(input);
4739 debug_printf_parse(": ch=%c (%d) escape=%d\n",
4740 ch, ch, dest.o_escape);
4745 syntax("unterminated here document");
4748 if (done_word(&dest, &ctx)) {
4752 done_pipe(&ctx, PIPE_SEQ);
4754 /* If we got nothing... */
4755 // TODO: test script consisting of just "&"
4756 if (pi->num_cmds == 0
4757 IF_HAS_KEYWORDS( && pi->res_word == RES_NONE)
4759 free_pipe_list(pi, 0);
4762 debug_printf_parse("parse_stream return %p\n", pi);
4764 debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
4766 *pstring = ctx.as_string.data;
4768 o_free_unsafe(&ctx.as_string);
4773 o_addchr(&ctx.as_string, ch);
4775 is_ifs = strchr(G.ifs, ch);
4776 is_special = strchr("<>;&|(){}#'" /* special outside of "str" */
4777 "\\$\"" USE_HUSH_TICK("`") /* always special */
4780 if (!is_special && !is_ifs) { /* ordinary char */
4781 o_addQchr(&dest, ch);
4782 if ((dest.o_assignment == MAYBE_ASSIGNMENT
4783 || dest.o_assignment == WORD_IS_KEYWORD)
4785 && is_assignment(dest.data)
4787 dest.o_assignment = DEFINITELY_ASSIGNMENT;
4793 if (done_word(&dest, &ctx)) {
4797 #if ENABLE_HUSH_CASE
4798 /* "case ... in <newline> word) ..." -
4799 * newlines are ignored (but ';' wouldn't be) */
4800 if (ctx.command->argv == NULL
4801 && ctx.ctx_res_w == RES_MATCH
4806 /* Treat newline as a command separator. */
4807 done_pipe(&ctx, PIPE_SEQ);
4808 debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt);
4810 if (fetch_heredocs(heredoc_cnt, &ctx, input))
4814 dest.o_assignment = MAYBE_ASSIGNMENT;
4816 /* note: if (is_ifs) continue;
4817 * will still trigger for us */
4820 if (end_trigger && end_trigger == ch
4821 && (heredoc_cnt == 0 || end_trigger != ';')
4823 //TODO: disallow "{ cmd }" without semicolon
4825 /* This is technically valid:
4826 * { cat <<HERE; }; echo Ok
4831 * but we don't support this.
4832 * We require heredoc to be in enclosing {}/(),
4835 syntax("unterminated here document");
4838 if (done_word(&dest, &ctx)) {
4841 done_pipe(&ctx, PIPE_SEQ);
4842 dest.o_assignment = MAYBE_ASSIGNMENT;
4843 /* Do we sit outside of any if's, loops or case's? */
4845 IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0))
4847 debug_printf_parse("parse_stream return %p: "
4848 "end_trigger char found\n",
4852 debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
4854 *pstring = ctx.as_string.data;
4856 o_free_unsafe(&ctx.as_string);
4858 return ctx.list_head;
4864 if (dest.o_assignment == MAYBE_ASSIGNMENT) {
4865 /* ch is a special char and thus this word
4866 * cannot be an assignment */
4867 dest.o_assignment = NOT_ASSIGNMENT;
4872 next = i_peek(input);
4877 if (dest.length == 0) {
4880 if (ch == EOF || ch == '\n')
4883 /* note: we do not add it to &ctx.as_string */
4886 //TODO: go back one char?
4887 o_addchr(&ctx.as_string, '\n');
4890 o_addQchr(&dest, ch);
4898 o_addchr(&dest, '\\');
4899 ch = i_getch(input);
4900 o_addchr(&dest, ch);
4902 o_addchr(&ctx.as_string, ch);
4906 if (handle_dollar(&ctx.as_string, &dest, input) != 0) {
4907 debug_printf_parse("parse_stream parse error: "
4908 "handle_dollar returned non-0\n");
4915 ch = i_getch(input);
4917 syntax("unterminated '");
4921 o_addchr(&ctx.as_string, ch);
4925 if (dest.o_assignment == NOT_ASSIGNMENT)
4926 o_addqchr(&dest, ch);
4928 o_addchr(&dest, ch);
4933 is_in_dquote ^= 1; /* invert */
4934 if (dest.o_assignment == NOT_ASSIGNMENT)
4937 #if ENABLE_HUSH_TICK
4939 //int pos = dest.length;
4940 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4941 o_addchr(&dest, '`');
4942 add_till_backquote(&dest, input);
4943 o_addchr(&dest, SPECIAL_VAR_SYMBOL);
4944 //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos);
4949 redir_fd = redirect_opt_num(&dest);
4950 if (done_word(&dest, &ctx)) {
4953 redir_style = REDIRECT_OVERWRITE;
4955 redir_style = REDIRECT_APPEND;
4956 ch = i_getch(input);
4958 o_addchr(&ctx.as_string, ch);
4962 else if (next == '(') {
4963 syntax(">(process) not supported");
4967 if (parse_redirect(&ctx, redir_fd, redir_style, input))
4971 redir_fd = redirect_opt_num(&dest);
4972 if (done_word(&dest, &ctx)) {
4975 redir_style = REDIRECT_INPUT;
4977 redir_style = REDIRECT_HEREDOC;
4979 debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt);
4980 ch = i_getch(input);
4982 o_addchr(&ctx.as_string, ch);
4984 } else if (next == '>') {
4985 redir_style = REDIRECT_IO;
4986 ch = i_getch(input);
4988 o_addchr(&ctx.as_string, ch);
4992 else if (next == '(') {
4993 syntax("<(process) not supported");
4997 if (parse_redirect(&ctx, redir_fd, redir_style, input))
5001 #if ENABLE_HUSH_CASE
5004 if (done_word(&dest, &ctx)) {
5007 done_pipe(&ctx, PIPE_SEQ);
5008 #if ENABLE_HUSH_CASE
5009 /* Eat multiple semicolons, detect
5010 * whether it means something special */
5015 ch = i_getch(input);
5017 o_addchr(&ctx.as_string, ch);
5019 if (ctx.ctx_res_w == RES_CASEI) {
5020 ctx.ctx_dsemicolon = 1;
5021 ctx.ctx_res_w = RES_MATCH;
5027 /* We just finished a cmd. New one may start
5028 * with an assignment */
5029 dest.o_assignment = MAYBE_ASSIGNMENT;
5032 if (done_word(&dest, &ctx)) {
5036 ch = i_getch(input);
5038 o_addchr(&ctx.as_string, ch);
5040 done_pipe(&ctx, PIPE_AND);
5042 done_pipe(&ctx, PIPE_BG);
5046 if (done_word(&dest, &ctx)) {
5049 #if ENABLE_HUSH_CASE
5050 if (ctx.ctx_res_w == RES_MATCH)
5051 break; /* we are in case's "word | word)" */
5053 if (next == '|') { /* || */
5054 ch = i_getch(input);
5056 o_addchr(&ctx.as_string, ch);
5058 done_pipe(&ctx, PIPE_OR);
5060 /* we could pick up a file descriptor choice here
5061 * with redirect_opt_num(), but bash doesn't do it.
5062 * "echo foo 2| cat" yields "foo 2". */
5067 #if ENABLE_HUSH_CASE
5068 /* "case... in [(]word)..." - skip '(' */
5069 if (ctx.ctx_res_w == RES_MATCH
5070 && ctx.command->argv == NULL /* not (word|(... */
5071 && dest.length == 0 /* not word(... */
5072 && dest.nonnull == 0 /* not ""(... */
5077 #if ENABLE_HUSH_FUNCTIONS
5078 if (dest.length != 0 /* not just () but word() */
5079 && dest.nonnull == 0 /* not a"b"c() */
5080 && ctx.command->argv == NULL /* it's the first word */
5081 //TODO: "func ( ) {...}" - note spaces - is valid format too in bash
5082 && i_peek(input) == ')'
5083 && !match_reserved_word(&dest)
5085 bb_error_msg("seems like a function definition");
5087 //if !BB_MMU o_addchr(&ctx.as_string...
5089 //TODO: do it properly.
5090 ch = i_getch(input);
5091 } while (ch == ' ' || ch == '\n');
5093 syntax("was expecting {");
5096 ch = 'F'; /* magic value */
5100 if (parse_group(&dest, &ctx, input, ch) != 0) {
5105 #if ENABLE_HUSH_CASE
5106 if (ctx.ctx_res_w == RES_MATCH)
5110 /* proper use of this character is caught by end_trigger:
5111 * if we see {, we call parse_group(..., end_trigger='}')
5112 * and it will match } earlier (not here). */
5113 syntax("unexpected } or )");
5117 bb_error_msg_and_die("BUG: unexpected %c\n", ch);
5123 struct parse_context *pctx;
5124 IF_HAS_KEYWORDS(struct parse_context *p2;)
5126 /* Clean up allocated tree.
5127 * Samples for finding leaks on syntax error recovery path.
5128 * Run them from interactive shell, watch pmap `pidof hush`.
5129 * while if false; then false; fi do break; done
5131 * while if false; then false; fi; do break; fi
5132 * Samples to catch leaks at execution:
5133 * while if (true | {true;}); then echo ok; fi; do break; done
5134 * while if (true | {true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
5138 /* Update pipe/command counts,
5139 * otherwise freeing may miss some */
5140 done_pipe(pctx, PIPE_SEQ);
5141 debug_printf_clean("freeing list %p from ctx %p\n",
5142 pctx->list_head, pctx);
5143 debug_print_tree(pctx->list_head, 0);
5144 free_pipe_list(pctx->list_head, 0);
5145 debug_printf_clean("freed list %p\n", pctx->list_head);
5147 o_free_unsafe(&pctx->as_string);
5149 IF_HAS_KEYWORDS(p2 = pctx->stack;)
5153 IF_HAS_KEYWORDS(pctx = p2;)
5154 } while (HAS_KEYWORDS && pctx);
5155 /* Free text, clear all dest fields */
5157 /* If we are not in top-level parse, we return,
5158 * our caller will propagate error.
5160 if (end_trigger != ';') {
5167 /* Discard cached input, force prompt */
5169 USE_HUSH_INTERACTIVE(input->promptme = 1;)
5174 /* Executing from string: eval, sh -c '...'
5175 * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
5176 * end_trigger controls how often we stop parsing
5177 * NUL: parse all, execute, return
5178 * ';': parse till ';' or newline, execute, repeat till EOF
5180 static void parse_and_run_stream(struct in_str *inp, int end_trigger)
5183 struct pipe *pipe_list;
5185 pipe_list = parse_stream(NULL, inp, end_trigger);
5186 if (!pipe_list) /* EOF */
5188 debug_print_tree(pipe_list, 0);
5189 debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
5190 run_and_free_list(pipe_list);
5194 static void parse_and_run_string(const char *s)
5196 struct in_str input;
5197 setup_string_in_str(&input, s);
5198 parse_and_run_stream(&input, '\0');
5201 static void parse_and_run_file(FILE *f)
5203 struct in_str input;
5204 setup_file_in_str(&input, f);
5205 parse_and_run_stream(&input, ';');
5208 /* Called a few times only (or even once if "sh -c") */
5209 static void block_signals(int second_time)
5214 mask = (1 << SIGQUIT);
5215 if (G_interactive_fd) {
5219 //TODO | (1 << SIGHUP)
5221 | (1 << SIGTTIN) | (1 << SIGTTOU) | (1 << SIGTSTP)
5226 G.non_DFL_mask = mask;
5229 sigprocmask(SIG_SETMASK, NULL, &G.blocked_set);
5233 sigaddset(&G.blocked_set, sig);
5237 sigdelset(&G.blocked_set, SIGCHLD);
5239 sigprocmask(SIG_SETMASK, &G.blocked_set,
5240 second_time ? NULL : &G.inherited_set);
5241 /* POSIX allows shell to re-enable SIGCHLD
5242 * even if it was SIG_IGN on entry */
5243 // G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
5245 signal(SIGCHLD, SIG_DFL); // SIGCHLD_handler);
5250 static void maybe_set_to_sigexit(int sig)
5252 void (*handler)(int);
5253 /* non_DFL_mask'ed signals are, well, masked,
5254 * no need to set handler for them.
5256 if (!((G.non_DFL_mask >> sig) & 1)) {
5257 handler = signal(sig, sigexit);
5258 if (handler == SIG_IGN) /* oops... restore back to IGN! */
5259 signal(sig, handler);
5262 /* Set handlers to restore tty pgrp and exit */
5263 static void set_fatal_handlers(void)
5265 /* We _must_ restore tty pgrp on fatal signals */
5267 maybe_set_to_sigexit(SIGILL );
5268 maybe_set_to_sigexit(SIGFPE );
5269 maybe_set_to_sigexit(SIGBUS );
5270 maybe_set_to_sigexit(SIGSEGV);
5271 maybe_set_to_sigexit(SIGTRAP);
5272 } /* else: hush is perfect. what SEGV? */
5273 maybe_set_to_sigexit(SIGABRT);
5274 /* bash 3.2 seems to handle these just like 'fatal' ones */
5275 maybe_set_to_sigexit(SIGPIPE);
5276 maybe_set_to_sigexit(SIGALRM);
5277 //TODO: disable and move down when proper SIGHUP handling is added
5278 maybe_set_to_sigexit(SIGHUP );
5279 /* if we are interactive, [SIGHUP,] SIGTERM and SIGINT are masked.
5280 * if we aren't interactive... but in this case
5281 * we never want to restore pgrp on exit, and this fn is not called */
5282 /*maybe_set_to_sigexit(SIGTERM);*/
5283 /*maybe_set_to_sigexit(SIGINT );*/
5287 static int set_mode(const char cstate, const char mode)
5289 int state = (cstate == '-' ? 1 : 0);
5291 case 'n': G.fake_mode = state; break;
5292 case 'x': /*G.debug_mode = state;*/ break;
5293 default: return EXIT_FAILURE;
5295 return EXIT_SUCCESS;
5298 int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
5299 int hush_main(int argc, char **argv)
5301 static const struct variable const_shell_ver = {
5303 .varstr = (char*)hush_version_str,
5304 .max_len = 1, /* 0 can provoke free(name) */
5308 int signal_mask_is_inited = 0;
5311 struct variable *cur_var;
5314 if (EXIT_SUCCESS) /* if EXIT_SUCCESS == 0, is already done */
5315 G.last_exitcode = EXIT_SUCCESS;
5317 G.argv0_for_re_execing = argv[0];
5319 /* Deal with HUSH_VERSION */
5320 G.shell_ver = const_shell_ver; /* copying struct here */
5321 G.top_var = &G.shell_ver;
5322 debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
5323 unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
5324 /* Initialize our shell local variables with the values
5325 * currently living in the environment */
5326 cur_var = G.top_var;
5329 char *value = strchr(*e, '=');
5330 if (value) { /* paranoia */
5331 cur_var->next = xzalloc(sizeof(*cur_var));
5332 cur_var = cur_var->next;
5333 cur_var->varstr = *e;
5334 cur_var->max_len = strlen(*e);
5335 cur_var->flg_export = 1;
5339 debug_printf_env("putenv '%s'\n", hush_version_str);
5340 putenv((char *)hush_version_str); /* reinstate HUSH_VERSION */
5341 #if ENABLE_FEATURE_EDITING
5342 G.line_input_state = new_line_input_t(FOR_SHELL);
5344 G.global_argc = argc;
5345 G.global_argv = argv;
5346 /* Initialize some more globals to non-zero values */
5348 #if ENABLE_HUSH_INTERACTIVE
5349 if (ENABLE_FEATURE_EDITING)
5350 cmdedit_set_initial_prompt();
5354 /* Shell is non-interactive at first. We need to call
5355 * block_signals(0) if we are going to execute "sh <script>",
5356 * "sh -c <cmds>" or login shell's /etc/profile and friends.
5357 * If we later decide that we are interactive, we run block_signals(0)
5358 * (or re-run block_signals(1) if we ran block_signals(0) before)
5359 * in order to intercept (more) signals.
5363 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */
5365 opt = getopt(argc, argv, "c:xins"
5375 G.root_pid = getpid();
5376 G.global_argv = argv + optind;
5377 if (!argv[optind]) {
5378 /* -c 'script' (no params): prevent empty $0 */
5379 *--G.global_argv = argv[0];
5381 } /* else -c 'script' PAR0 PAR1: $0 is PAR0 */
5382 G.global_argc = argc - optind;
5383 block_signals(0); /* 0: called 1st time */
5384 parse_and_run_string(optarg);
5387 /* Well, we cannot just declare interactiveness,
5388 * we have to have some stuff (ctty, etc) */
5389 /* G_interactive_fd++; */
5392 /* "-s" means "read from stdin", but this is how we always
5393 * operate, so simply do nothing here. */
5396 case '<': /* "big heredoc" support */
5397 full_write(STDOUT_FILENO, optarg, strlen(optarg));
5400 G.root_pid = bb_strtou(optarg, &optarg, 16);
5402 G.last_bg_pid = bb_strtou(optarg, &optarg, 16);
5404 G.last_exitcode = bb_strtou(optarg, &optarg, 16);
5405 # if ENABLE_HUSH_LOOPS
5407 G.depth_of_loop = bb_strtou(optarg, &optarg, 16);
5412 set_local_var(xstrdup(optarg), 0, opt == 'R');
5417 if (!set_mode('-', opt))
5421 fprintf(stderr, "Usage: sh [FILE]...\n"
5422 " or: sh -c command [args]...\n\n");
5428 } /* option parsing loop */
5431 G.root_pid = getpid();
5433 /* If we are login shell... */
5434 if (argv[0] && argv[0][0] == '-') {
5436 /* XXX what should argv be while sourcing /etc/profile? */
5437 debug_printf("sourcing /etc/profile\n");
5438 input = fopen_for_read("/etc/profile");
5439 if (input != NULL) {
5440 close_on_exec_on(fileno(input));
5441 block_signals(0); /* 0: called 1st time */
5442 signal_mask_is_inited = 1;
5443 parse_and_run_file(input);
5446 /* bash: after sourcing /etc/profile,
5447 * tries to source (in the given order):
5448 * ~/.bash_profile, ~/.bash_login, ~/.profile,
5449 * stopping of first found. --noprofile turns this off.
5450 * bash also sources ~/.bash_logout on exit.
5451 * If called as sh, skips .bash_XXX files.
5458 * "bash <script>" (which is never interactive (unless -i?))
5459 * sources $BASH_ENV here (without scanning $PATH).
5460 * If called as sh, does the same but with $ENV.
5462 debug_printf("running script '%s'\n", argv[optind]);
5463 G.global_argv = argv + optind;
5464 G.global_argc = argc - optind;
5465 input = xfopen_for_read(argv[optind]);
5466 close_on_exec_on(fileno(input));
5467 if (!signal_mask_is_inited)
5468 block_signals(0); /* 0: called 1st time */
5469 parse_and_run_file(input);
5470 #if ENABLE_FEATURE_CLEAN_UP
5476 /* Up to here, shell was non-interactive. Now it may become one.
5477 * NB: don't forget to (re)run block_signals(0/1) as needed.
5480 /* A shell is interactive if the '-i' flag was given, or if all of
5481 * the following conditions are met:
5483 * no arguments remaining or the -s flag given
5484 * standard input is a terminal
5485 * standard output is a terminal
5486 * Refer to Posix.2, the description of the 'sh' utility.
5489 if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
5490 G.saved_tty_pgrp = tcgetpgrp(STDIN_FILENO);
5491 debug_printf("saved_tty_pgrp:%d\n", G.saved_tty_pgrp);
5492 //TODO: "interactive" and "have job control" are two different things.
5493 //If tcgetpgrp fails here, "have job control" is false, but "interactive"
5494 //should stay on! Currently, we mix these into one.
5495 if (G.saved_tty_pgrp >= 0) {
5496 /* try to dup stdin to high fd#, >= 255 */
5497 G_interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
5498 if (G_interactive_fd < 0) {
5499 /* try to dup to any fd */
5500 G_interactive_fd = dup(STDIN_FILENO);
5501 if (G_interactive_fd < 0)
5503 G_interactive_fd = 0;
5505 // TODO: track & disallow any attempts of user
5506 // to (inadvertently) close/redirect it
5509 debug_printf("interactive_fd:%d\n", G_interactive_fd);
5510 if (G_interactive_fd) {
5513 /* We are indeed interactive shell, and we will perform
5514 * job control. Setting up for that. */
5516 close_on_exec_on(G_interactive_fd);
5517 /* If we were run as 'hush &', sleep until we are
5518 * in the foreground (tty pgrp == our pgrp).
5519 * If we get started under a job aware app (like bash),
5520 * make sure we are now in charge so we don't fight over
5521 * who gets the foreground */
5523 shell_pgrp = getpgrp();
5524 G.saved_tty_pgrp = tcgetpgrp(G_interactive_fd);
5525 if (G.saved_tty_pgrp == shell_pgrp)
5527 /* send TTIN to ourself (should stop us) */
5528 kill(- shell_pgrp, SIGTTIN);
5530 /* Block some signals */
5531 block_signals(signal_mask_is_inited);
5532 /* Set other signals to restore saved_tty_pgrp */
5533 set_fatal_handlers();
5534 /* Put ourselves in our own process group */
5535 bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
5536 /* Grab control of the terminal */
5537 tcsetpgrp(G_interactive_fd, getpid());
5538 /* -1 is special - makes xfuncs longjmp, not exit
5539 * (we reset die_sleep = 0 whereever we [v]fork) */
5541 if (setjmp(die_jmp)) {
5542 /* xfunc has failed! die die die */
5543 hush_exit(xfunc_error_retval);
5545 } else if (!signal_mask_is_inited) {
5546 block_signals(0); /* 0: called 1st time */
5547 } /* else: block_signals(0) was done before */
5548 #elif ENABLE_HUSH_INTERACTIVE
5549 /* No job control compiled in, only prompt/line editing */
5550 if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
5551 G_interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
5552 if (G_interactive_fd < 0) {
5553 /* try to dup to any fd */
5554 G_interactive_fd = dup(STDIN_FILENO);
5555 if (G_interactive_fd < 0)
5557 G_interactive_fd = 0;
5560 if (G_interactive_fd) {
5561 close_on_exec_on(G_interactive_fd);
5562 block_signals(signal_mask_is_inited);
5563 } else if (!signal_mask_is_inited) {
5567 /* We have interactiveness code disabled */
5568 if (!signal_mask_is_inited) {
5573 * if interactive but not a login shell, sources ~/.bashrc
5574 * (--norc turns this off, --rcfile <file> overrides)
5577 if (!ENABLE_FEATURE_SH_EXTRA_QUIET && G_interactive_fd) {
5578 printf("\n\n%s hush - the humble shell\n", bb_banner);
5579 printf("Enter 'help' for a list of built-in commands.\n\n");
5582 parse_and_run_file(stdin);
5585 #if ENABLE_FEATURE_CLEAN_UP
5586 if (G.cwd != bb_msg_unknown)
5588 cur_var = G.top_var->next;
5590 struct variable *tmp = cur_var;
5591 if (!cur_var->max_len)
5592 free(cur_var->varstr);
5593 cur_var = cur_var->next;
5597 hush_exit(G.last_exitcode);
5602 int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
5603 int lash_main(int argc, char **argv)
5605 //bb_error_msg("lash is deprecated, please use hush instead");
5606 return hush_main(argc, argv);
5614 static int builtin_trap(char **argv)
5621 G.traps = xzalloc(sizeof(G.traps[0]) * NSIG);
5625 /* No args: print all trapped. This isn't 100% correct as we
5626 * should be escaping the cmd so that it can be pasted back in
5628 for (i = 0; i < NSIG; ++i)
5630 printf("trap -- '%s' %s\n", G.traps[i], get_signame(i));
5631 return EXIT_SUCCESS;
5636 /* If first arg is decimal: reset all specified signals */
5637 sig = bb_strtou(*argv, NULL, 10);
5643 sig = get_signum(*argv++);
5644 if (sig < 0 || sig >= NSIG) {
5646 /* Mimic bash message exactly */
5647 bb_perror_msg("trap: %s: invalid signal specification", argv[i]);
5652 G.traps[sig] = xstrdup(new_cmd);
5654 debug_printf("trap: setting SIG%s (%i) to '%s'",
5655 get_signame(sig), sig, G.traps[sig]);
5657 /* There is no signal for 0 (EXIT) */
5662 sigaddset(&G.blocked_set, sig);
5664 /* There was a trap handler, we are removing it
5665 * (if sig has non-DFL handling,
5666 * we don't need to do anything) */
5667 if (sig < 32 && (G.non_DFL_mask & (1 << sig)))
5669 sigdelset(&G.blocked_set, sig);
5671 sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
5676 /* First arg is "-": reset all specified to default */
5677 /* First arg is "": ignore all specified */
5678 /* Everything else: execute first arg upon signal */
5680 bb_error_msg("trap: invalid arguments");
5681 return EXIT_FAILURE;
5683 if (NOT_LONE_DASH(*argv))
5689 static int builtin_true(char **argv UNUSED_PARAM)
5694 static int builtin_test(char **argv)
5701 return test_main(argc, argv - argc);
5704 static int builtin_echo(char **argv)
5711 return echo_main(argc, argv - argc);
5714 static int builtin_eval(char **argv)
5716 int rcode = EXIT_SUCCESS;
5719 char *str = expand_strvec_to_string(argv);
5721 * eval "echo Hi; done" ("done" is syntax error):
5722 * "echo Hi" will not execute too.
5724 parse_and_run_string(str);
5726 rcode = G.last_exitcode;
5731 static int builtin_cd(char **argv)
5733 const char *newdir = argv[1];
5734 if (newdir == NULL) {
5735 /* bash does nothing (exitcode 0) if HOME is ""; if it's unset,
5736 * bash says "bash: cd: HOME not set" and does nothing (exitcode 1)
5738 newdir = getenv("HOME") ? : "/";
5740 if (chdir(newdir)) {
5741 /* Mimic bash message exactly */
5742 bb_perror_msg("cd: %s", newdir);
5743 return EXIT_FAILURE;
5746 return EXIT_SUCCESS;
5749 static int builtin_exec(char **argv)
5751 if (*++argv == NULL)
5752 return EXIT_SUCCESS; /* bash does this */
5757 // FIXME: if exec fails, bash does NOT exit! We do...
5758 pseudo_exec_argv(&dummy, argv, 0, NULL);
5763 static int builtin_exit(char **argv)
5765 debug_printf_exec("%s()\n", __func__);
5766 // TODO: bash does it ONLY on top-level sh exit (+interacive only?)
5767 //puts("exit"); /* bash does it */
5768 // TODO: warn if we have background jobs: "There are stopped jobs"
5769 // On second consecutive 'exit', exit anyway.
5770 if (*++argv == NULL)
5771 hush_exit(G.last_exitcode);
5772 /* mimic bash: exit 123abc == exit 255 + error msg */
5773 xfunc_error_retval = 255;
5774 /* bash: exit -2 == exit 254, no error msg */
5775 hush_exit(xatoi(*argv) & 0xff);
5778 static int builtin_export(char **argv)
5780 if (*++argv == NULL) {
5782 // ash emits: export VAR='VAL'
5783 // bash: declare -x VAR="VAL"
5784 // (both also escape as needed (quotes, $, etc))
5789 return EXIT_SUCCESS;
5796 value = strchr(name, '=');
5798 /* They are exporting something without a =VALUE */
5799 struct variable *var;
5801 var = get_local_var(name);
5803 var->flg_export = 1;
5804 debug_printf_env("%s: putenv '%s'\n", __func__, var->varstr);
5805 putenv(var->varstr);
5807 /* bash does not return an error when trying to export
5808 * an undefined variable. Do likewise. */
5811 set_local_var(xstrdup(name), 1, 0);
5814 return EXIT_SUCCESS;
5818 /* built-in 'fg' and 'bg' handler */
5819 static int builtin_fg_bg(char **argv)
5824 if (!G_interactive_fd)
5825 return EXIT_FAILURE;
5826 /* If they gave us no args, assume they want the last backgrounded task */
5828 for (pi = G.job_list; pi; pi = pi->next) {
5829 if (pi->jobid == G.last_jobid) {
5833 bb_error_msg("%s: no current job", argv[0]);
5834 return EXIT_FAILURE;
5836 if (sscanf(argv[1], "%%%d", &jobnum) != 1) {
5837 bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]);
5838 return EXIT_FAILURE;
5840 for (pi = G.job_list; pi; pi = pi->next) {
5841 if (pi->jobid == jobnum) {
5845 bb_error_msg("%s: %d: no such job", argv[0], jobnum);
5846 return EXIT_FAILURE;
5848 // TODO: bash prints a string representation
5849 // of job being foregrounded (like "sleep 1 | cat")
5850 if (argv[0][0] == 'f') {
5851 /* Put the job into the foreground. */
5852 tcsetpgrp(G_interactive_fd, pi->pgrp);
5855 /* Restart the processes in the job */
5856 debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_cmds, pi->pgrp);
5857 for (i = 0; i < pi->num_cmds; i++) {
5858 debug_printf_jobs("reviving pid %d\n", pi->cmds[i].pid);
5859 pi->cmds[i].is_stopped = 0;
5861 pi->stopped_cmds = 0;
5863 i = kill(- pi->pgrp, SIGCONT);
5865 if (errno == ESRCH) {
5866 delete_finished_bg_job(pi);
5867 return EXIT_SUCCESS;
5869 bb_perror_msg("kill (SIGCONT)");
5872 if (argv[0][0] == 'f') {
5874 return checkjobs_and_fg_shell(pi);
5876 return EXIT_SUCCESS;
5880 #if ENABLE_HUSH_HELP
5881 static int builtin_help(char **argv UNUSED_PARAM)
5883 const struct built_in_command *x;
5886 "Built-in commands:\n"
5887 "------------------\n");
5888 for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) {
5889 printf("%s\t%s\n", x->cmd, x->descr);
5892 return EXIT_SUCCESS;
5897 static int builtin_jobs(char **argv UNUSED_PARAM)
5900 const char *status_string;
5902 for (job = G.job_list; job; job = job->next) {
5903 if (job->alive_cmds == job->stopped_cmds)
5904 status_string = "Stopped";
5906 status_string = "Running";
5908 printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
5910 return EXIT_SUCCESS;
5914 static int builtin_pwd(char **argv UNUSED_PARAM)
5917 return EXIT_SUCCESS;
5920 static int builtin_read(char **argv)
5923 const char *name = argv[1] ? argv[1] : "REPLY";
5924 //TODO: check that argv[1] is a valid variable name
5926 string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name), NULL);
5927 return set_local_var(string, 0, 0);
5930 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
5931 * built-in 'set' handler
5933 * set [-abCefhmnuvx] [-o option] [argument...]
5934 * set [+abCefhmnuvx] [+o option] [argument...]
5935 * set -- [argument...]
5938 * Implementations shall support the options in both their hyphen and
5939 * plus-sign forms. These options can also be specified as options to sh.
5941 * Write out all variables and their values: set
5942 * Set $1, $2, and $3 and set "$#" to 3: set c a b
5943 * Turn on the -x and -v options: set -xv
5944 * Unset all positional parameters: set --
5945 * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x"
5946 * Set the positional parameters to the expansion of x, even if x expands
5947 * with a leading '-' or '+': set -- $x
5949 * So far, we only support "set -- [argument...]" and some of the short names.
5951 static int builtin_set(char **argv)
5954 char **pp, **g_argv;
5955 char *arg = *++argv;
5959 for (e = G.top_var; e; e = e->next)
5961 return EXIT_SUCCESS;
5965 if (!strcmp(arg, "--")) {
5970 if (arg[0] == '+' || arg[0] == '-') {
5971 for (n = 1; arg[n]; ++n)
5972 if (set_mode(arg[0], arg[n]))
5978 } while ((arg = *++argv) != NULL);
5979 /* Now argv[0] is 1st argument */
5981 /* Only reset global_argv if we didn't process anything */
5983 return EXIT_SUCCESS;
5986 /* NB: G.global_argv[0] ($0) is never freed/changed */
5987 g_argv = G.global_argv;
5988 if (G.global_args_malloced) {
5994 G.global_args_malloced = 1;
5995 pp = xzalloc(sizeof(pp[0]) * 2);
5996 pp[0] = g_argv[0]; /* retain $0 */
5999 /* This realloc's G.global_argv */
6000 G.global_argv = pp = add_strings_to_strings(g_argv, argv, /*dup:*/ 1);
6007 return EXIT_SUCCESS;
6009 /* Nothing known, so abort */
6011 bb_error_msg("set: %s: invalid option", arg);
6012 return EXIT_FAILURE;
6015 static int builtin_shift(char **argv)
6021 if (n >= 0 && n < G.global_argc) {
6022 if (G.global_args_malloced) {
6025 free(G.global_argv[m++]);
6028 memmove(&G.global_argv[1], &G.global_argv[n+1],
6029 G.global_argc * sizeof(G.global_argv[0]));
6030 return EXIT_SUCCESS;
6032 return EXIT_FAILURE;
6035 static int builtin_source(char **argv)
6039 if (*++argv == NULL)
6040 return EXIT_FAILURE;
6042 /* XXX search through $PATH is missing */
6043 input = fopen_or_warn(*argv, "r");
6045 /* bb_perror_msg("%s", *argv); - done by fopen_or_warn */
6046 return EXIT_FAILURE;
6048 close_on_exec_on(fileno(input));
6050 /* Now run the file */
6052 /* XXX argv and argc are broken; need to save old G.global_argv
6053 * (pointer only is OK!) on this stack frame,
6054 * set G.global_argv=argv+1, recurse, and restore. */
6055 parse_and_run_file(input);
6057 return G.last_exitcode;
6060 static int builtin_umask(char **argv)
6063 const char *arg = argv[1];
6065 //TODO: umask may take chmod-like symbolic masks
6066 new_umask = bb_strtou(arg, NULL, 8);
6068 //Message? bash examples:
6069 //bash: umask: 'q': invalid symbolic mode operator
6070 //bash: umask: 999: octal number out of range
6071 return EXIT_FAILURE;
6074 new_umask = umask(0);
6075 printf("%.3o\n", (unsigned) new_umask);
6076 /* fall through and restore new_umask which we set to 0 */
6079 return EXIT_SUCCESS;
6082 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */
6083 static int builtin_unset(char **argv)
6089 return EXIT_SUCCESS;
6092 if (argv[0][0] == '-') {
6093 switch (argv[0][1]) {
6099 bb_error_msg("unset: %s: invalid option", *argv);
6100 return EXIT_FAILURE;
6102 //TODO: disallow "unset -vf ..." too
6109 if (unset_local_var(*argv)) {
6110 /* unset <nonexistent_var> doesn't fail.
6111 * Error is when one tries to unset RO var.
6112 * Message was printed by unset_local_var. */
6116 #if ENABLE_HUSH_FUNCTIONS
6118 unset_local_func(*argv);
6126 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */
6127 static int builtin_wait(char **argv)
6129 int ret = EXIT_SUCCESS;
6132 if (*++argv == NULL) {
6133 /* Don't care about wait results */
6134 /* Note 1: must wait until there are no more children */
6135 /* Note 2: must be interruptible */
6137 * $ sleep 3 & sleep 6 & wait
6142 * $ sleep 3 & sleep 6 & wait
6146 * ^C <-- after ~4 sec from keyboard
6149 sigaddset(&G.blocked_set, SIGCHLD);
6150 sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
6153 if (errno == ECHILD)
6155 /* Wait for SIGCHLD or any other signal of interest */
6156 /* sigtimedwait with infinite timeout: */
6157 sig = sigwaitinfo(&G.blocked_set, NULL);
6159 sig = check_and_run_traps(sig);
6160 if (sig && sig != SIGCHLD) { /* see note 2 */
6166 sigdelset(&G.blocked_set, SIGCHLD);
6167 sigprocmask(SIG_SETMASK, &G.blocked_set, NULL);
6171 /* This is probably buggy wrt interruptible-ness */
6173 pid_t pid = bb_strtou(*argv, NULL, 10);
6175 /* mimic bash message */
6176 bb_error_msg("wait: '%s': not a pid or valid job spec", *argv);
6177 return EXIT_FAILURE;
6179 if (waitpid(pid, &status, 0) == pid) {
6180 if (WIFSIGNALED(status))
6181 ret = 128 + WTERMSIG(status);
6182 else if (WIFEXITED(status))
6183 ret = WEXITSTATUS(status);
6187 bb_perror_msg("wait %s", *argv);
6196 #if ENABLE_HUSH_LOOPS
6197 static int builtin_break(char **argv)
6199 if (G.depth_of_loop == 0) {
6200 bb_error_msg("%s: only meaningful in a loop", argv[0]);
6201 return EXIT_SUCCESS; /* bash compat */
6203 G.flag_break_continue++; /* BC_BREAK = 1 */
6204 G.depth_break_continue = 1;
6206 G.depth_break_continue = bb_strtou(argv[1], NULL, 10);
6207 if (errno || !G.depth_break_continue || argv[2]) {
6208 bb_error_msg("%s: bad arguments", argv[0]);
6209 G.flag_break_continue = BC_BREAK;
6210 G.depth_break_continue = UINT_MAX;
6213 if (G.depth_of_loop < G.depth_break_continue)
6214 G.depth_break_continue = G.depth_of_loop;
6215 return EXIT_SUCCESS;
6218 static int builtin_continue(char **argv)
6220 G.flag_break_continue = 1; /* BC_CONTINUE = 2 = 1+1 */
6221 return builtin_break(argv);
projects / oweals / busybox.git / blob