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
45 * Bash stuff (maybe optionally enable?):
46 * &> and >& redirection of stdout+stderr
48 * reserved words: [[ ]] function select
49 * substrings ${var:1:5}
52 * grep for "TODO" and fix (some of them are easy)
53 * change { and } from special chars to reserved words
54 * builtins: return, ulimit
55 * follow IFS rules more precisely, including update semantics
56 * figure out what to do with backslash-newline
57 * continuation lines, both explicit and implicit - done?
59 * ^Z handling (and explain it in comments for mere humans)
60 * separate job control from interactiveness
61 * (testcase: booting with init=/bin/hush does not show prompt (2009-04))
63 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
65 #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */
67 /* #include <dmalloc.h> */
74 # define PIPE_BUF 4096 /* amount of buffering in a pipe */
78 /* Debug build knobs */
79 #define LEAK_HUNTING 0
80 #define BUILD_AS_NOMMU 0
81 /* Enable/disable sanity checks. Ok to enable in production,
82 * only adds a bit of bloat. Set to >1 to get non-production level verbosity.
83 * Keeping 1 for now even in released versions.
93 # define USE_FOR_NOMMU(...) __VA_ARGS__
94 # define USE_FOR_MMU(...)
97 #if defined SINGLE_APPLET_MAIN
98 /* STANDALONE does not make sense, and won't compile */
99 # undef CONFIG_FEATURE_SH_STANDALONE
100 # undef ENABLE_FEATURE_SH_STANDALONE
101 # undef USE_FEATURE_SH_STANDALONE
102 # define SKIP_FEATURE_SH_STANDALONE(...) __VA_ARGS__
103 # define ENABLE_FEATURE_SH_STANDALONE 0
104 # define USE_FEATURE_SH_STANDALONE(...)
105 # define SKIP_FEATURE_SH_STANDALONE(...) __VA_ARGS__
108 #if !ENABLE_HUSH_INTERACTIVE
109 # undef ENABLE_FEATURE_EDITING
110 # define ENABLE_FEATURE_EDITING 0
111 # undef ENABLE_FEATURE_EDITING_FANCY_PROMPT
112 # define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
115 /* Do we support ANY keywords? */
116 #if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
117 # define HAS_KEYWORDS 1
118 # define IF_HAS_KEYWORDS(...) __VA_ARGS__
119 # define IF_HAS_NO_KEYWORDS(...)
121 # define HAS_KEYWORDS 0
122 # define IF_HAS_KEYWORDS(...)
123 # define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__
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)
141 #define ERR_PTR ((void*)(long)1)
143 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
145 #define SPECIAL_VAR_SYMBOL 3
147 static const char hush_version_str
[] ALIGN1
= "HUSH_VERSION="BB_VER
;
149 /* This supports saving pointers malloced in vfork child,
150 * to be freed in the parent. One pointer is saved in
151 * G.argv_from_re_execing global var instead. TODO: unify.
154 typedef struct nommu_save_t
{
161 /* The descrip member of this structure is only used to make
162 * debugging output pretty */
163 static const struct {
165 signed char default_fd
;
169 { O_RDONLY
, 0, "<" },
170 { O_CREAT
|O_TRUNC
|O_WRONLY
, 1, ">" },
171 { O_CREAT
|O_APPEND
|O_WRONLY
, 1, ">>" },
172 { O_RDONLY
, 0, "<<" },
173 { O_CREAT
|O_RDWR
, 1, "<>" },
174 /* Should not be needed. Bogus default_fd helps in debugging */
175 /* { O_RDONLY, 77, "<<" }, */
178 typedef enum reserved_style
{
187 #if ENABLE_HUSH_LOOPS
194 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
199 /* two pseudo-keywords support contrived "case" syntax: */
200 RES_MATCH
, /* "word)" */
201 RES_CASEI
, /* "this command is inside CASE" */
208 typedef struct o_string
{
210 int length
; /* position where data is appended */
212 /* Protect newly added chars against globbing
213 * (by prepending \ to *, ?, [, \) */
216 /* At least some part of the string was inside '' or "",
217 * possibly empty one: word"", wo''rd etc. */
219 smallint has_empty_slot
;
220 smallint o_assignment
; /* 0:maybe, 1:yes, 2:no */
223 MAYBE_ASSIGNMENT
= 0,
224 DEFINITELY_ASSIGNMENT
= 1,
226 WORD_IS_KEYWORD
= 3, /* not assigment, but next word may be: "if v=xyz cmd;" */
228 /* Used for initialization: o_string foo = NULL_O_STRING; */
229 #define NULL_O_STRING { NULL }
231 /* I can almost use ordinary FILE*. Is open_memstream() universally
232 * available? Where is it documented? */
233 typedef struct in_str
{
235 /* eof_flag=1: last char in ->p is really an EOF */
236 char eof_flag
; /* meaningless if ->p == NULL */
238 #if ENABLE_HUSH_INTERACTIVE
240 smallint promptmode
; /* 0: PS1, 1: PS2 */
243 int (*get
) (struct in_str
*);
244 int (*peek
) (struct in_str
*);
246 #define i_getch(input) ((input)->get(input))
247 #define i_peek(input) ((input)->peek(input))
249 struct redir_struct
{
250 struct redir_struct
*next
;
251 char *rd_filename
; /* filename */
252 int rd_fd
; /* fd to redirect */
253 /* fd to redirect to, or -3 if rd_fd is to be closed (n>&-) */
255 smallint rd_type
; /* (enum redir_type) */
256 /* note: for heredocs, rd_filename contains heredoc delimiter,
257 * and subsequently heredoc itself; and rd_dup is a bitmask:
258 * 1: do we need to trim leading tabs?
259 * 2: is heredoc quoted (<<'delim' syntax) ?
262 typedef enum redir_type
{
263 REDIRECT_INVALID
= 0,
265 REDIRECT_OVERWRITE
= 2,
267 REDIRECT_HEREDOC
= 4,
269 REDIRECT_HEREDOC2
= 6, /* REDIRECT_HEREDOC after heredoc is loaded */
272 REDIRFD_SYNTAX_ERR
= -2,
273 REDIRFD_TO_FILE
= -1,
274 /* otherwise, rd_fd is redirected to rd_dup */
276 HEREDOC_SKIPTABS
= 1,
282 pid_t pid
; /* 0 if exited */
283 int assignment_cnt
; /* how many argv[i] are assignments? */
284 smallint is_stopped
; /* is the command currently running? */
285 smallint grp_type
; /* GRP_xxx */
287 #define GRP_SUBSHELL 1
288 #if ENABLE_HUSH_FUNCTIONS
289 # define GRP_FUNCTION 2
291 struct pipe
*group
; /* if non-NULL, this "command" is { list },
292 * ( list ), or a compound statement */
294 char *group_as_string
;
296 #if ENABLE_HUSH_FUNCTIONS
297 struct function
*child_func
;
298 /* This field is used to prevent a bug here:
299 * while...do f1() {a;}; f1; f1 {b;}; f1; done
300 * When we execute "f1() {a;}" cmd, we create new function and clear
301 * cmd->group, cmd->group_as_string, cmd->argv[0].
302 * when we execute "f1 {b;}", we notice that f1 exists,
303 * and that it's "parent cmd" struct is still "alive",
304 * we put those fields back into cmd->xxx
305 * (struct function has ->parent_cmd ptr to facilitate that).
306 * When we loop back, we can execute "f1() {a;}" again and set f1 correctly.
307 * Without this trick, loop would execute a;b;b;b;...
308 * instead of correct sequence a;b;a;b;...
309 * When command is freed, it severs the link
310 * (sets ->child_func->parent_cmd to NULL).
313 char **argv
; /* command name and arguments */
314 /* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
315 * and on execution these are substituted with their values.
316 * Substitution can make _several_ words out of one argv[n]!
317 * Example: argv[0]=='.^C*^C.' here: echo .$*.
318 * References of the form ^C`cmd arg^C are `cmd arg` substitutions.
320 struct redir_struct
*redirects
; /* I/O redirections */
325 int num_cmds
; /* total number of commands in pipe */
326 int alive_cmds
; /* number of commands running (not exited) */
327 int stopped_cmds
; /* number of commands alive, but stopped */
329 int jobid
; /* job number */
330 pid_t pgrp
; /* process group ID for the job */
331 char *cmdtext
; /* name of job */
333 struct command
*cmds
; /* array of commands in pipe */
334 smallint followup
; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
335 IF_HAS_KEYWORDS(smallint pi_inverted
;) /* "! cmd | cmd" */
336 IF_HAS_KEYWORDS(smallint res_word
;) /* needed for if, for, while, until... */
338 typedef enum pipe_style
{
345 /* This holds pointers to the various results of parsing */
346 struct parse_context
{
347 /* linked list of pipes */
348 struct pipe
*list_head
;
349 /* last pipe (being constructed right now) */
351 /* last command in pipe (being constructed right now) */
352 struct command
*command
;
353 /* last redirect in command->redirects list */
354 struct redir_struct
*pending_redirect
;
360 smallint ctx_inverted
; /* "! cmd | cmd" */
362 smallint ctx_dsemicolon
; /* ";;" seen */
364 /* bitmask of FLAG_xxx, for figuring out valid reserved words */
366 /* group we are enclosed in:
367 * example: "if pipe1; pipe2; then pipe3; fi"
368 * when we see "if" or "then", we malloc and copy current context,
369 * and make ->stack point to it. then we parse pipeN.
370 * when closing "then" / fi" / whatever is found,
371 * we move list_head into ->stack->command->group,
372 * copy ->stack into current context, and delete ->stack.
373 * (parsing of { list } and ( list ) doesn't use this method)
375 struct parse_context
*stack
;
379 /* On program start, environ points to initial environment.
380 * putenv adds new pointers into it, unsetenv removes them.
381 * Neither of these (de)allocates the strings.
382 * setenv allocates new strings in malloc space and does putenv,
383 * and thus setenv is unusable (leaky) for shell's purposes */
384 #define setenv(...) setenv_is_leaky_dont_use()
386 struct variable
*next
;
387 char *varstr
; /* points to "name=" portion */
388 int max_len
; /* if > 0, name is part of initial env; else name is malloced */
389 smallint flg_export
; /* putenv should be done on this var */
390 smallint flg_read_only
;
398 #if ENABLE_HUSH_FUNCTIONS
400 struct function
*next
;
402 struct command
*parent_cmd
;
405 char *body_as_string
;
411 /* "Globals" within this file */
412 /* Sorted roughly by size (smaller offsets == smaller code) */
414 #if ENABLE_HUSH_INTERACTIVE
415 /* 'interactive_fd' is a fd# open to ctty, if we have one
416 * _AND_ if we decided to act interactively */
420 #define G_interactive_fd (G.interactive_fd)
422 #define G_interactive_fd 0
424 #if ENABLE_FEATURE_EDITING
425 line_input_t
*line_input_state
;
431 pid_t saved_tty_pgrp
;
433 struct pipe
*job_list
;
434 struct pipe
*toplevel_list
;
435 //// smallint ctrl_z_flag;
437 smallint flag_SIGINT
;
438 #if ENABLE_HUSH_LOOPS
439 smallint flag_break_continue
;
442 smallint exiting
; /* used to prevent EXIT trap recursion */
443 /* These four support $?, $#, and $1 */
444 smalluint last_exitcode
;
445 /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */
446 smalluint global_args_malloced
;
447 /* how many non-NULL argv's we have. NB: $# + 1 */
451 char *argv0_for_re_execing
;
452 char **argv_from_re_execing
;
454 #if ENABLE_HUSH_LOOPS
455 unsigned depth_break_continue
;
456 unsigned depth_of_loop
;
460 struct variable
*top_var
; /* = &G.shell_ver (set in main()) */
461 struct variable shell_ver
;
462 #if ENABLE_HUSH_FUNCTIONS
463 struct function
*top_func
;
465 /* Signal and trap handling */
466 // unsigned count_SIGCHLD;
467 // unsigned handled_SIGCHLD;
468 /* which signals have non-DFL handler (even with no traps set)? */
469 unsigned non_DFL_mask
;
470 char **traps
; /* char *traps[NSIG] */
471 sigset_t blocked_set
;
472 sigset_t inherited_set
;
474 unsigned long memleak_value
;
477 char user_input_buf
[ENABLE_FEATURE_EDITING
? BUFSIZ
: 2];
478 #if ENABLE_FEATURE_SH_STANDALONE
479 struct nofork_save_area nofork_save
;
482 sigjmp_buf toplevel_jb
;
485 #define G (*ptr_to_globals)
486 /* Not #defining name to G.name - this quickly gets unwieldy
487 * (too many defines). Also, I actually prefer to see when a variable
488 * is global, thus "G." prefix is a useful hint */
489 #define INIT_G() do { \
490 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
494 /* Function prototypes for builtins */
495 static int builtin_cd(char **argv
);
496 static int builtin_echo(char **argv
);
497 static int builtin_eval(char **argv
);
498 static int builtin_exec(char **argv
);
499 static int builtin_exit(char **argv
);
500 static int builtin_export(char **argv
);
502 static int builtin_fg_bg(char **argv
);
503 static int builtin_jobs(char **argv
);
506 static int builtin_help(char **argv
);
509 static int builtin_memleak(char **argv
);
511 static int builtin_pwd(char **argv
);
512 static int builtin_read(char **argv
);
513 static int builtin_set(char **argv
);
514 static int builtin_shift(char **argv
);
515 static int builtin_source(char **argv
);
516 static int builtin_test(char **argv
);
517 static int builtin_trap(char **argv
);
518 static int builtin_true(char **argv
);
519 static int builtin_umask(char **argv
);
520 static int builtin_unset(char **argv
);
521 static int builtin_wait(char **argv
);
522 #if ENABLE_HUSH_LOOPS
523 static int builtin_break(char **argv
);
524 static int builtin_continue(char **argv
);
527 /* Table of built-in functions. They can be forked or not, depending on
528 * context: within pipes, they fork. As simple commands, they do not.
529 * When used in non-forking context, they can change global variables
530 * in the parent shell process. If forked, of course they cannot.
531 * For example, 'unset foo | whatever' will parse and run, but foo will
532 * still be set at the end. */
533 struct built_in_command
{
535 int (*function
)(char **argv
);
538 #define BLTIN(cmd, func, help) { cmd, func, help }
540 #define BLTIN(cmd, func, help) { cmd, func }
544 /* For now, echo and test are unconditionally enabled.
545 * Maybe make it configurable? */
546 static const struct built_in_command bltins
[] = {
547 BLTIN("." , builtin_source
, "Run commands in a file"),
548 BLTIN(":" , builtin_true
, "No-op"),
549 BLTIN("[" , builtin_test
, "Test condition"),
551 BLTIN("bg" , builtin_fg_bg
, "Resume a job in the background"),
553 #if ENABLE_HUSH_LOOPS
554 BLTIN("break" , builtin_break
, "Exit from a loop"),
556 BLTIN("cd" , builtin_cd
, "Change directory"),
557 #if ENABLE_HUSH_LOOPS
558 BLTIN("continue", builtin_continue
, "Start new loop iteration"),
560 BLTIN("echo" , builtin_echo
, "Write to stdout"),
561 BLTIN("eval" , builtin_eval
, "Construct and run shell command"),
562 BLTIN("exec" , builtin_exec
, "Execute command, don't return to shell"),
563 BLTIN("exit" , builtin_exit
, "Exit"),
564 BLTIN("export" , builtin_export
, "Set environment variable"),
566 BLTIN("fg" , builtin_fg_bg
, "Bring job into the foreground"),
569 BLTIN("help" , builtin_help
, "List shell built-in commands"),
572 BLTIN("jobs" , builtin_jobs
, "List active jobs"),
575 BLTIN("memleak" , builtin_memleak
, "Debug tool"),
577 BLTIN("pwd" , builtin_pwd
, "Print current directory"),
578 BLTIN("read" , builtin_read
, "Input environment variable"),
579 // BLTIN("return" , builtin_return , "Return from a function"),
580 BLTIN("set" , builtin_set
, "Set/unset shell local variables"),
581 BLTIN("shift" , builtin_shift
, "Shift positional parameters"),
582 BLTIN("test" , builtin_test
, "Test condition"),
583 BLTIN("trap" , builtin_trap
, "Trap signals"),
584 // BLTIN("ulimit" , builtin_return , "Control resource limits"),
585 BLTIN("umask" , builtin_umask
, "Set file creation mask"),
586 BLTIN("unset" , builtin_unset
, "Unset environment variable"),
587 BLTIN("wait" , builtin_wait
, "Wait for process"),
594 /* prevent disasters with G.debug_indent < 0 */
595 # define indent() fprintf(stderr, "%*s", (G.debug_indent * 2) & 0xff, "")
596 # define debug_enter() (G.debug_indent++)
597 # define debug_leave() (G.debug_indent--)
599 # define indent() ((void)0)
600 # define debug_enter() ((void)0)
601 # define debug_leave() ((void)0)
605 # define debug_printf(...) (indent(), fprintf(stderr, __VA_ARGS__))
608 #ifndef debug_printf_parse
609 # define debug_printf_parse(...) (indent(), fprintf(stderr, __VA_ARGS__))
612 #ifndef debug_printf_exec
613 #define debug_printf_exec(...) (indent(), fprintf(stderr, __VA_ARGS__))
616 #ifndef debug_printf_env
617 # define debug_printf_env(...) (indent(), fprintf(stderr, __VA_ARGS__))
620 #ifndef debug_printf_jobs
621 # define debug_printf_jobs(...) (indent(), fprintf(stderr, __VA_ARGS__))
622 # define DEBUG_JOBS 1
624 # define DEBUG_JOBS 0
627 #ifndef debug_printf_expand
628 # define debug_printf_expand(...) (indent(), fprintf(stderr, __VA_ARGS__))
629 # define DEBUG_EXPAND 1
631 # define DEBUG_EXPAND 0
634 #ifndef debug_printf_glob
635 # define debug_printf_glob(...) (indent(), fprintf(stderr, __VA_ARGS__))
636 # define DEBUG_GLOB 1
638 # define DEBUG_GLOB 0
641 #ifndef debug_printf_list
642 # define debug_printf_list(...) (indent(), fprintf(stderr, __VA_ARGS__))
645 #ifndef debug_printf_subst
646 # define debug_printf_subst(...) (indent(), fprintf(stderr, __VA_ARGS__))
649 #ifndef debug_printf_clean
650 # define debug_printf_clean(...) (indent(), fprintf(stderr, __VA_ARGS__))
651 # define DEBUG_CLEAN 1
653 # define DEBUG_CLEAN 0
657 static void debug_print_strings(const char *prefix
, char **vv
)
660 fprintf(stderr
, "%s:\n", prefix
);
662 fprintf(stderr
, " '%s'\n", *vv
++);
665 #define debug_print_strings(prefix, vv) ((void)0)
669 /* Leak hunting. Use hush_leaktool.sh for post-processing.
672 static void *xxmalloc(int lineno
, size_t size
)
674 void *ptr
= xmalloc((size
+ 0xff) & ~0xff);
675 fdprintf(2, "line %d: malloc %p\n", lineno
, ptr
);
678 static void *xxrealloc(int lineno
, void *ptr
, size_t size
)
680 ptr
= xrealloc(ptr
, (size
+ 0xff) & ~0xff);
681 fdprintf(2, "line %d: realloc %p\n", lineno
, ptr
);
684 static char *xxstrdup(int lineno
, const char *str
)
686 char *ptr
= xstrdup(str
);
687 fdprintf(2, "line %d: strdup %p\n", lineno
, ptr
);
690 static void xxfree(void *ptr
)
692 fdprintf(2, "free %p\n", ptr
);
695 #define xmalloc(s) xxmalloc(__LINE__, s)
696 #define xrealloc(p, s) xxrealloc(__LINE__, p, s)
697 #define xstrdup(s) xxstrdup(__LINE__, s)
698 #define free(p) xxfree(p)
702 /* Syntax and runtime errors. They always abort scripts.
703 * In interactive use they usually discard unparsed and/or unexecuted commands
704 * and return to the prompt.
705 * HUSH_DEBUG >= 2 prints line number in this file where it was detected.
708 # define die_if_script(lineno, fmt...) die_if_script(fmt)
709 # define syntax_error(lineno, msg) syntax_error(msg)
710 # define syntax_error_at(lineno, msg) syntax_error_at(msg)
711 # define syntax_error_unterm_ch(lineno, ch) syntax_error_unterm_ch(ch)
712 # define syntax_error_unterm_str(lineno, s) syntax_error_unterm_str(s)
713 # define syntax_error_unexpected_ch(lineno, ch) syntax_error_unexpected_ch(ch)
716 static void die_if_script(unsigned lineno
, const char *fmt
, ...)
721 bb_error_msg("hush.c:%u", lineno
);
724 bb_verror_msg(fmt
, p
, NULL
);
726 if (!G_interactive_fd
)
730 static void syntax_error(unsigned lineno
, const char *msg
)
733 die_if_script(lineno
, "syntax error: %s", msg
);
735 die_if_script(lineno
, "syntax error", NULL
);
738 static void syntax_error_at(unsigned lineno
, const char *msg
)
740 die_if_script(lineno
, "syntax error at '%s'", msg
);
743 /* It so happens that all such cases are totally fatal
744 * even if shell is interactive: EOF while looking for closing
745 * delimiter. There is nowhere to read stuff from after that,
746 * it's EOF! The only choice is to terminate.
748 static void syntax_error_unterm_ch(unsigned lineno
, char ch
) NORETURN
;
749 static void syntax_error_unterm_ch(unsigned lineno
, char ch
)
754 die_if_script(lineno
, "syntax error: unterminated %s", msg
);
758 static void syntax_error_unterm_str(unsigned lineno
, const char *s
)
760 die_if_script(lineno
, "syntax error: unterminated %s", s
);
763 static void syntax_error_unexpected_ch(unsigned lineno
, char ch
)
768 die_if_script(lineno
, "syntax error: unexpected %s", msg
);
772 # undef die_if_script
774 # undef syntax_error_at
775 # undef syntax_error_unterm_ch
776 # undef syntax_error_unterm_str
777 # undef syntax_error_unexpected_ch
779 # define die_if_script(fmt...) die_if_script(__LINE__, fmt)
780 # define syntax_error(msg) syntax_error(__LINE__, msg)
781 # define syntax_error_at(msg) syntax_error_at(__LINE__, msg)
782 # define syntax_error_unterm_ch(ch) syntax_error_unterm_ch(__LINE__, ch)
783 # define syntax_error_unterm_str(s) syntax_error_unterm_str(__LINE__, s)
784 # define syntax_error_unexpected_ch(ch) syntax_error_unexpected_ch(__LINE__, ch)
790 static int glob_needed(const char *s
)
795 if (*s
== '*' || *s
== '[' || *s
== '?')
802 static int is_well_formed_var_name(const char *s
, char terminator
)
804 if (!s
|| !(isalpha(*s
) || *s
== '_'))
807 while (isalnum(*s
) || *s
== '_')
809 return *s
== terminator
;
812 /* Replace each \x with x in place, return ptr past NUL. */
813 static char *unbackslash(char *src
)
819 if ((*dst
++ = *src
++) == '\0')
825 static char **add_strings_to_strings(char **strings
, char **add
, int need_to_dup
)
846 v
= xrealloc(strings
, (count1
+ count2
+ 1) * sizeof(char*));
847 v
[count1
+ count2
] = NULL
;
850 v
[count1
+ i
] = (need_to_dup
? xstrdup(add
[i
]) : add
[i
]);
854 static char **xx_add_strings_to_strings(int lineno
, char **strings
, char **add
, int need_to_dup
)
856 char **ptr
= add_strings_to_strings(strings
, add
, need_to_dup
);
857 fdprintf(2, "line %d: add_strings_to_strings %p\n", lineno
, ptr
);
860 #define add_strings_to_strings(strings, add, need_to_dup) \
861 xx_add_strings_to_strings(__LINE__, strings, add, need_to_dup)
864 static char **add_string_to_strings(char **strings
, char *add
)
869 return add_strings_to_strings(strings
, v
, /*dup:*/ 0);
872 static char **xx_add_string_to_strings(int lineno
, char **strings
, char *add
)
874 char **ptr
= add_string_to_strings(strings
, add
);
875 fdprintf(2, "line %d: add_string_to_strings %p\n", lineno
, ptr
);
878 #define add_string_to_strings(strings, add) \
879 xx_add_string_to_strings(__LINE__, strings, add)
882 static void putenv_all(char **strings
)
887 debug_printf_env("putenv '%s'\n", *strings
);
892 static char **putenv_all_and_save_old(char **strings
)
902 eq
= strchr(*strings
, '=');
905 v
= getenv(*strings
);
908 /* v points to VAL in VAR=VAL, go back to VAR */
909 v
-= (eq
- *strings
) + 1;
910 old
= add_string_to_strings(old
, v
);
919 static void free_strings_and_unsetenv(char **strings
, int unset
)
929 debug_printf_env("unsetenv '%s'\n", *v
);
937 static void free_strings(char **strings
)
939 free_strings_and_unsetenv(strings
, 0);
943 /* Basic theory of signal handling in shell
944 * ========================================
945 * This does not describe what hush does, rather, it is current understanding
946 * what it _should_ do. If it doesn't, it's a bug.
947 * http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap
949 * Signals are handled only after each pipe ("cmd | cmd | cmd" thing)
950 * is finished or backgrounded. It is the same in interactive and
951 * non-interactive shells, and is the same regardless of whether
952 * a user trap handler is installed or a shell special one is in effect.
953 * ^C or ^Z from keyboard seem to execute "at once" because it usually
954 * backgrounds (i.e. stops) or kills all members of currently running
957 * Wait builtin in interruptible by signals for which user trap is set
958 * or by SIGINT in interactive shell.
960 * Trap handlers will execute even within trap handlers. (right?)
962 * User trap handlers are forgotten when subshell ("(cmd)") is entered.
964 * If job control is off, backgrounded commands ("cmd &")
965 * have SIGINT, SIGQUIT set to SIG_IGN.
967 * Commands run in command substitution ("`cmd`")
968 * have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN.
970 * Ordinary commands have signals set to SIG_IGN/DFL set as inherited
971 * by the shell from its parent.
973 * Siganls which differ from SIG_DFL action
974 * (note: child (i.e., [v]forked) shell is not an interactive shell):
977 * SIGTERM (interactive): ignore
978 * SIGHUP (interactive):
979 * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit
980 * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore
981 * (note that ^Z is handled not by trapping SIGTSTP, but by seeing
982 * that all pipe members are stopped) (right?)
983 * SIGINT (interactive): wait for last pipe, ignore the rest
984 * of the command line, show prompt. NB: ^C does not send SIGINT
985 * to interactive shell while shell is waiting for a pipe,
986 * since shell is bg'ed (is not in foreground process group).
987 * (check/expand this)
988 * Example 1: this waits 5 sec, but does not execute ls:
989 * "echo $$; sleep 5; ls -l" + "kill -INT <pid>"
990 * Example 2: this does not wait and does not execute ls:
991 * "echo $$; sleep 5 & wait; ls -l" + "kill -INT <pid>"
992 * Example 3: this does not wait 5 sec, but executes ls:
993 * "sleep 5; ls -l" + press ^C
995 * (What happens to signals which are IGN on shell start?)
996 * (What happens with signal mask on shell start?)
998 * Implementation in hush
999 * ======================
1000 * We use in-kernel pending signal mask to determine which signals were sent.
1001 * We block all signals which we don't want to take action immediately,
1002 * i.e. we block all signals which need to have special handling as described
1003 * above, and all signals which have traps set.
1004 * After each pipe execution, we extract any pending signals via sigtimedwait()
1007 * unsigned non_DFL_mask: a mask of such "special" signals
1008 * sigset_t blocked_set: current blocked signal set
1011 * clear bit in blocked_set unless it is also in non_DFL_mask
1012 * "trap 'cmd' SIGxxx":
1013 * set bit in blocked_set (even if 'cmd' is '')
1014 * after [v]fork, if we plan to be a shell:
1015 * nothing for {} child shell (say, "true | { true; true; } | true")
1016 * unset all traps if () shell.
1017 * after [v]fork, if we plan to exec:
1018 * POSIX says pending signal mask is cleared in child - no need to clear it.
1019 * Restore blocked signal set to one inherited by shell just prior to exec.
1021 * Note: as a result, we do not use signal handlers much. The only uses
1022 * are to count SIGCHLDs [disabled - bug somewhere, + bloat]
1023 * and to restore tty pgrp on signal-induced exit.
1026 //static void SIGCHLD_handler(int sig UNUSED_PARAM)
1028 // G.count_SIGCHLD++;
1031 static int check_and_run_traps(int sig
)
1033 static const struct timespec zero_timespec
= { 0, 0 };
1034 smalluint save_rcode
;
1040 sig
= sigtimedwait(&G
.blocked_set
, NULL
, &zero_timespec
);
1045 if (G
.traps
&& G
.traps
[sig
]) {
1046 if (G
.traps
[sig
][0]) {
1047 /* We have user-defined handler */
1048 char *argv
[] = { NULL
, xstrdup(G
.traps
[sig
]), NULL
};
1049 save_rcode
= G
.last_exitcode
;
1052 G
.last_exitcode
= save_rcode
;
1053 } /* else: "" trap, ignoring signal */
1056 /* not a trap: special action */
1059 // G.count_SIGCHLD++;
1068 default: /* ignored: */
1069 /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */
1078 /* After [v]fork, in child: do not restore tty pgrp on xfunc death */
1079 #define disable_restore_tty_pgrp_on_exit() (die_sleep = 0)
1080 /* After [v]fork, in parent: restore tty pgrp on xfunc death */
1081 #define enable_restore_tty_pgrp_on_exit() (die_sleep = -1)
1083 /* Restores tty foreground process group, and exits.
1084 * May be called as signal handler for fatal signal
1085 * (will faithfully resend signal to itself, producing correct exit state)
1086 * or called directly with -EXITCODE.
1087 * We also call it if xfunc is exiting. */
1088 static void sigexit(int sig
) NORETURN
;
1089 static void sigexit(int sig
)
1091 /* Disable all signals: job control, SIGPIPE, etc. */
1092 sigprocmask_allsigs(SIG_BLOCK
);
1094 /* Careful: we can end up here after [v]fork. Do not restore
1095 * tty pgrp then, only top-level shell process does that */
1096 if (G_interactive_fd
&& getpid() == G
.root_pid
)
1097 tcsetpgrp(G_interactive_fd
, G
.saved_tty_pgrp
);
1099 /* Not a signal, just exit */
1103 kill_myself_with_sig(sig
); /* does not return */
1107 #define disable_restore_tty_pgrp_on_exit() ((void)0)
1108 #define enable_restore_tty_pgrp_on_exit() ((void)0)
1112 /* Restores tty foreground process group, and exits. */
1113 static void hush_exit(int exitcode
) NORETURN
;
1114 static void hush_exit(int exitcode
)
1116 if (G
.exiting
<= 0 && G
.traps
&& G
.traps
[0] && G
.traps
[0][0]) {
1117 /* Prevent recursion:
1118 * trap "echo Hi; exit" EXIT; exit
1120 char *argv
[] = { NULL
, G
.traps
[0], NULL
};
1128 fflush(NULL
); /* flush all streams */
1129 sigexit(- (exitcode
& 0xff));
1136 static const char *set_cwd(void)
1138 /* xrealloc_getcwd_or_warn(arg) calls free(arg),
1139 * we must not try to free(bb_msg_unknown) */
1140 if (G
.cwd
== bb_msg_unknown
)
1142 G
.cwd
= xrealloc_getcwd_or_warn((char *)G
.cwd
);
1144 G
.cwd
= bb_msg_unknown
;
1149 /* Get/check local shell variables */
1150 static struct variable
*get_local_var(const char *name
)
1152 struct variable
*cur
;
1158 for (cur
= G
.top_var
; cur
; cur
= cur
->next
) {
1159 if (strncmp(cur
->varstr
, name
, len
) == 0 && cur
->varstr
[len
] == '=')
1165 static const char *get_local_var_value(const char *src
)
1167 struct variable
*var
= get_local_var(src
);
1169 return strchr(var
->varstr
, '=') + 1;
1173 /* str holds "NAME=VAL" and is expected to be malloced.
1174 * We take ownership of it.
1178 * -1: if NAME is set, leave export status alone
1179 * if NAME is not set, do not export
1180 * flg_read_only is set only when we handle -R var=val
1183 #define set_local_var(str, flg_export, flg_read_only) \
1184 set_local_var(str, flg_export)
1186 static int set_local_var(char *str
, int flg_export
, int flg_read_only
)
1188 struct variable
*cur
;
1192 value
= strchr(str
, '=');
1193 if (!value
) { /* not expected to ever happen? */
1198 name_len
= value
- str
+ 1; /* including '=' */
1199 cur
= G
.top_var
; /* cannot be NULL (we have HUSH_VERSION and it's RO) */
1201 if (strncmp(cur
->varstr
, str
, name_len
) != 0) {
1203 /* Bail out. Note that now cur points
1204 * to last var in linked list */
1210 /* We found an existing var with this name */
1212 if (cur
->flg_read_only
) {
1216 bb_error_msg("%s: readonly variable", str
);
1220 debug_printf_env("%s: unsetenv '%s'\n", __func__
, str
);
1221 unsetenv(str
); /* just in case */
1223 if (strcmp(cur
->varstr
, str
) == 0) {
1228 if (cur
->max_len
>= strlen(str
)) {
1229 /* This one is from startup env, reuse space */
1230 strcpy(cur
->varstr
, str
);
1233 /* max_len == 0 signifies "malloced" var, which we can
1234 * (and has to) free */
1238 goto set_str_and_exp
;
1241 /* Not found - create next variable struct */
1242 cur
->next
= xzalloc(sizeof(*cur
));
1248 cur
->flg_read_only
= flg_read_only
;
1251 if (flg_export
== 1)
1252 cur
->flg_export
= 1;
1253 if (cur
->flg_export
) {
1254 debug_printf_env("%s: putenv '%s'\n", __func__
, cur
->varstr
);
1255 return putenv(cur
->varstr
);
1260 static int unset_local_var(const char *name
)
1262 struct variable
*cur
;
1263 struct variable
*prev
= prev
; /* for gcc */
1267 return EXIT_SUCCESS
;
1268 name_len
= strlen(name
);
1271 if (strncmp(cur
->varstr
, name
, name_len
) == 0 && cur
->varstr
[name_len
] == '=') {
1272 if (cur
->flg_read_only
) {
1273 bb_error_msg("%s: readonly variable", name
);
1274 return EXIT_FAILURE
;
1276 /* prev is ok to use here because 1st variable, HUSH_VERSION,
1277 * is ro, and we cannot reach this code on the 1st pass */
1278 prev
->next
= cur
->next
;
1279 debug_printf_env("%s: unsetenv '%s'\n", __func__
, cur
->varstr
);
1280 bb_unsetenv(cur
->varstr
);
1284 return EXIT_SUCCESS
;
1289 return EXIT_SUCCESS
;
1292 #if ENABLE_SH_MATH_SUPPORT
1293 #define is_name(c) ((c) == '_' || isalpha((unsigned char)(c)))
1294 #define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c)))
1295 static char *endofname(const char *name
)
1303 if (!is_in_name(*p
))
1309 static void arith_set_local_var(const char *name
, const char *val
, int flags
)
1311 /* arith code doesnt malloc space, so do it for it */
1312 char *var
= xasprintf("%s=%s", name
, val
);
1313 set_local_var(var
, flags
, 0);
1321 static int static_get(struct in_str
*i
)
1330 static int static_peek(struct in_str
*i
)
1335 #if ENABLE_HUSH_INTERACTIVE
1337 static void cmdedit_set_initial_prompt(void)
1339 if (ENABLE_FEATURE_EDITING_FANCY_PROMPT
) {
1340 G
.PS1
= getenv("PS1");
1347 static const char* setup_prompt_string(int promptmode
)
1349 const char *prompt_str
;
1350 debug_printf("setup_prompt_string %d ", promptmode
);
1351 if (!ENABLE_FEATURE_EDITING_FANCY_PROMPT
) {
1352 /* Set up the prompt */
1353 if (promptmode
== 0) { /* PS1 */
1355 G
.PS1
= xasprintf("%s %c ", G
.cwd
, (geteuid() != 0) ? '$' : '#');
1360 prompt_str
= (promptmode
== 0) ? G
.PS1
: G
.PS2
;
1361 debug_printf("result '%s'\n", prompt_str
);
1365 static void get_user_input(struct in_str
*i
)
1368 const char *prompt_str
;
1370 prompt_str
= setup_prompt_string(i
->promptmode
);
1371 #if ENABLE_FEATURE_EDITING
1372 /* Enable command line editing only while a command line
1373 * is actually being read */
1376 /* buglet: SIGINT will not make new prompt to appear _at once_,
1377 * only after <Enter>. (^C will work) */
1378 r
= read_line_input(prompt_str
, G
.user_input_buf
, BUFSIZ
-1, G
.line_input_state
);
1379 /* catch *SIGINT* etc (^C is handled by read_line_input) */
1380 check_and_run_traps(0);
1381 } while (r
== 0 || G
.flag_SIGINT
); /* repeat if ^C or SIGINT */
1382 i
->eof_flag
= (r
< 0);
1383 if (i
->eof_flag
) { /* EOF/error detected */
1384 G
.user_input_buf
[0] = EOF
; /* yes, it will be truncated, it's ok */
1385 G
.user_input_buf
[1] = '\0';
1390 fputs(prompt_str
, stdout
);
1392 G
.user_input_buf
[0] = r
= fgetc(i
->file
);
1393 /*G.user_input_buf[1] = '\0'; - already is and never changed */
1394 //do we need check_and_run_traps(0)? (maybe only if stdin)
1395 } while (G
.flag_SIGINT
);
1396 i
->eof_flag
= (r
== EOF
);
1398 i
->p
= G
.user_input_buf
;
1401 #endif /* INTERACTIVE */
1403 /* This is the magic location that prints prompts
1404 * and gets data back from the user */
1405 static int file_get(struct in_str
*i
)
1409 /* If there is data waiting, eat it up */
1410 if (i
->p
&& *i
->p
) {
1411 #if ENABLE_HUSH_INTERACTIVE
1415 if (i
->eof_flag
&& !*i
->p
)
1417 /* note: ch is never NUL */
1419 /* need to double check i->file because we might be doing something
1420 * more complicated by now, like sourcing or substituting. */
1421 #if ENABLE_HUSH_INTERACTIVE
1422 if (G_interactive_fd
&& i
->promptme
&& i
->file
== stdin
) {
1425 } while (!*i
->p
); /* need non-empty line */
1426 i
->promptmode
= 1; /* PS2 */
1431 do ch
= fgetc(i
->file
); while (ch
== '\0');
1433 debug_printf("file_get: got '%c' %d\n", ch
, ch
);
1434 #if ENABLE_HUSH_INTERACTIVE
1441 /* All callers guarantee this routine will never
1442 * be used right after a newline, so prompting is not needed.
1444 static int file_peek(struct in_str
*i
)
1447 if (i
->p
&& *i
->p
) {
1448 if (i
->eof_flag
&& !i
->p
[1])
1451 /* note: ch is never NUL */
1453 do ch
= fgetc(i
->file
); while (ch
== '\0');
1454 i
->eof_flag
= (ch
== EOF
);
1455 i
->peek_buf
[0] = ch
;
1456 i
->peek_buf
[1] = '\0';
1458 debug_printf("file_peek: got '%c' %d\n", ch
, ch
);
1462 static void setup_file_in_str(struct in_str
*i
, FILE *f
)
1464 i
->peek
= file_peek
;
1466 #if ENABLE_HUSH_INTERACTIVE
1468 i
->promptmode
= 0; /* PS1 */
1474 static void setup_string_in_str(struct in_str
*i
, const char *s
)
1476 i
->peek
= static_peek
;
1477 i
->get
= static_get
;
1478 #if ENABLE_HUSH_INTERACTIVE
1480 i
->promptmode
= 0; /* PS1 */
1490 #define B_CHUNK (32 * sizeof(char*))
1492 static void o_reset_to_empty_unquoted(o_string
*o
)
1500 static void o_free(o_string
*o
)
1503 memset(o
, 0, sizeof(*o
));
1506 static ALWAYS_INLINE
void o_free_unsafe(o_string
*o
)
1511 static void o_grow_by(o_string
*o
, int len
)
1513 if (o
->length
+ len
> o
->maxlen
) {
1514 o
->maxlen
+= (2*len
> B_CHUNK
? 2*len
: B_CHUNK
);
1515 o
->data
= xrealloc(o
->data
, 1 + o
->maxlen
);
1519 static void o_addchr(o_string
*o
, int ch
)
1521 debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch
, o
->length
, o
);
1523 o
->data
[o
->length
] = ch
;
1525 o
->data
[o
->length
] = '\0';
1528 static void o_addblock(o_string
*o
, const char *str
, int len
)
1531 memcpy(&o
->data
[o
->length
], str
, len
);
1533 o
->data
[o
->length
] = '\0';
1537 static void o_addstr(o_string
*o
, const char *str
)
1539 o_addblock(o
, str
, strlen(str
));
1541 static void nommu_addchr(o_string
*o
, int ch
)
1547 #define nommu_addchr(o, str) ((void)0)
1550 static void o_addstr_with_NUL(o_string
*o
, const char *str
)
1552 o_addblock(o
, str
, strlen(str
) + 1);
1555 static void o_addblock_duplicate_backslash(o_string
*o
, const char *str
, int len
)
1560 && (*str
!= '*' && *str
!= '?' && *str
!= '[')
1568 /* My analysis of quoting semantics tells me that state information
1569 * is associated with a destination, not a source.
1571 static void o_addqchr(o_string
*o
, int ch
)
1574 char *found
= strchr("*?[\\", ch
);
1579 o
->data
[o
->length
] = '\\';
1582 o
->data
[o
->length
] = ch
;
1584 o
->data
[o
->length
] = '\0';
1587 static void o_addQchr(o_string
*o
, int ch
)
1590 if (o
->o_escape
&& strchr("*?[\\", ch
)) {
1592 o
->data
[o
->length
] = '\\';
1596 o
->data
[o
->length
] = ch
;
1598 o
->data
[o
->length
] = '\0';
1601 static void o_addQstr(o_string
*o
, const char *str
, int len
)
1604 o_addblock(o
, str
, len
);
1610 int ordinary_cnt
= strcspn(str
, "*?[\\");
1611 if (ordinary_cnt
> len
) /* paranoia */
1613 o_addblock(o
, str
, ordinary_cnt
);
1614 if (ordinary_cnt
== len
)
1616 str
+= ordinary_cnt
;
1617 len
-= ordinary_cnt
+ 1; /* we are processing + 1 char below */
1621 if (ch
) { /* it is necessarily one of "*?[\\" */
1623 o
->data
[o
->length
] = '\\';
1627 o
->data
[o
->length
] = ch
;
1629 o
->data
[o
->length
] = '\0';
1633 /* A special kind of o_string for $VAR and `cmd` expansion.
1634 * It contains char* list[] at the beginning, which is grown in 16 element
1635 * increments. Actual string data starts at the next multiple of 16 * (char*).
1636 * list[i] contains an INDEX (int!) into this string data.
1637 * It means that if list[] needs to grow, data needs to be moved higher up
1638 * but list[i]'s need not be modified.
1639 * NB: remembering how many list[i]'s you have there is crucial.
1640 * o_finalize_list() operation post-processes this structure - calculates
1641 * and stores actual char* ptrs in list[]. Oh, it NULL terminates it as well.
1643 #if DEBUG_EXPAND || DEBUG_GLOB
1644 static void debug_print_list(const char *prefix
, o_string
*o
, int n
)
1646 char **list
= (char**)o
->data
;
1647 int string_start
= ((n
+ 0xf) & ~0xf) * sizeof(list
[0]);
1651 fprintf(stderr
, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d\n",
1652 prefix
, list
, n
, string_start
, o
->length
, o
->maxlen
);
1655 fprintf(stderr
, " list[%d]=%d '%s' %p\n", i
, (int)list
[i
],
1656 o
->data
+ (int)list
[i
] + string_start
,
1657 o
->data
+ (int)list
[i
] + string_start
);
1661 const char *p
= o
->data
+ (int)list
[n
- 1] + string_start
;
1663 fprintf(stderr
, " total_sz:%ld\n", (long)((p
+ strlen(p
) + 1) - o
->data
));
1667 #define debug_print_list(prefix, o, n) ((void)0)
1670 /* n = o_save_ptr_helper(str, n) "starts new string" by storing an index value
1671 * in list[n] so that it points past last stored byte so far.
1672 * It returns n+1. */
1673 static int o_save_ptr_helper(o_string
*o
, int n
)
1675 char **list
= (char**)o
->data
;
1679 if (!o
->has_empty_slot
) {
1680 string_start
= ((n
+ 0xf) & ~0xf) * sizeof(list
[0]);
1681 string_len
= o
->length
- string_start
;
1682 if (!(n
& 0xf)) { /* 0, 0x10, 0x20...? */
1683 debug_printf_list("list[%d]=%d string_start=%d (growing)\n", n
, string_len
, string_start
);
1684 /* list[n] points to string_start, make space for 16 more pointers */
1685 o
->maxlen
+= 0x10 * sizeof(list
[0]);
1686 o
->data
= xrealloc(o
->data
, o
->maxlen
+ 1);
1687 list
= (char**)o
->data
;
1688 memmove(list
+ n
+ 0x10, list
+ n
, string_len
);
1689 o
->length
+= 0x10 * sizeof(list
[0]);
1691 debug_printf_list("list[%d]=%d string_start=%d\n",
1692 n
, string_len
, string_start
);
1695 /* We have empty slot at list[n], reuse without growth */
1696 string_start
= ((n
+1 + 0xf) & ~0xf) * sizeof(list
[0]); /* NB: n+1! */
1697 string_len
= o
->length
- string_start
;
1698 debug_printf_list("list[%d]=%d string_start=%d (empty slot)\n",
1699 n
, string_len
, string_start
);
1700 o
->has_empty_slot
= 0;
1702 list
[n
] = (char*)(ptrdiff_t)string_len
;
1706 /* "What was our last o_save_ptr'ed position (byte offset relative o->data)?" */
1707 static int o_get_last_ptr(o_string
*o
, int n
)
1709 char **list
= (char**)o
->data
;
1710 int string_start
= ((n
+ 0xf) & ~0xf) * sizeof(list
[0]);
1712 return ((int)(ptrdiff_t)list
[n
-1]) + string_start
;
1715 /* o_glob performs globbing on last list[], saving each result
1716 * as a new list[]. */
1717 static int o_glob(o_string
*o
, int n
)
1723 debug_printf_glob("start o_glob: n:%d o->data:%p\n", n
, o
->data
);
1725 return o_save_ptr_helper(o
, n
);
1726 pattern
= o
->data
+ o_get_last_ptr(o
, n
);
1727 debug_printf_glob("glob pattern '%s'\n", pattern
);
1728 if (!glob_needed(pattern
)) {
1730 o
->length
= unbackslash(pattern
) - o
->data
;
1731 debug_printf_glob("glob pattern '%s' is literal\n", pattern
);
1732 return o_save_ptr_helper(o
, n
);
1735 memset(&globdata
, 0, sizeof(globdata
));
1736 gr
= glob(pattern
, 0, NULL
, &globdata
);
1737 debug_printf_glob("glob('%s'):%d\n", pattern
, gr
);
1738 if (gr
== GLOB_NOSPACE
)
1739 bb_error_msg_and_die("out of memory during glob");
1740 if (gr
== GLOB_NOMATCH
) {
1741 globfree(&globdata
);
1744 if (gr
!= 0) { /* GLOB_ABORTED ? */
1745 //TODO: testcase for bad glob pattern behavior
1746 bb_error_msg("glob(3) error %d on '%s'", gr
, pattern
);
1748 if (globdata
.gl_pathv
&& globdata
.gl_pathv
[0]) {
1749 char **argv
= globdata
.gl_pathv
;
1750 o
->length
= pattern
- o
->data
; /* "forget" pattern */
1752 o_addstr_with_NUL(o
, *argv
);
1753 n
= o_save_ptr_helper(o
, n
);
1759 globfree(&globdata
);
1761 debug_print_list("o_glob returning", o
, n
);
1765 /* If o->o_glob == 1, glob the string so far remembered.
1766 * Otherwise, just finish current list[] and start new */
1767 static int o_save_ptr(o_string
*o
, int n
)
1769 if (o
->o_glob
) { /* if globbing is requested */
1770 /* If o->has_empty_slot, list[n] was already globbed
1771 * (if it was requested back then when it was filled)
1772 * so don't do that again! */
1773 if (!o
->has_empty_slot
)
1774 return o_glob(o
, n
); /* o_save_ptr_helper is inside */
1776 return o_save_ptr_helper(o
, n
);
1779 /* "Please convert list[n] to real char* ptrs, and NULL terminate it." */
1780 static char **o_finalize_list(o_string
*o
, int n
)
1785 n
= o_save_ptr(o
, n
); /* force growth for list[n] if necessary */
1787 debug_print_list("finalized", o
, n
);
1788 debug_printf_expand("finalized n:%d\n", n
);
1789 list
= (char**)o
->data
;
1790 string_start
= ((n
+ 0xf) & ~0xf) * sizeof(list
[0]);
1794 list
[n
] = o
->data
+ (int)(ptrdiff_t)list
[n
] + string_start
;
1800 /* Expansion can recurse */
1801 #if ENABLE_HUSH_TICK
1802 static int process_command_subs(o_string
*dest
, const char *s
);
1804 static char *expand_string_to_string(const char *str
);
1806 #define parse_stream_dquoted(as_string, dest, input, dquote_end) \
1807 parse_stream_dquoted(dest, input, dquote_end)
1809 static int parse_stream_dquoted(o_string
*as_string
,
1811 struct in_str
*input
,
1814 /* expand_strvec_to_strvec() takes a list of strings, expands
1815 * all variable references within and returns a pointer to
1816 * a list of expanded strings, possibly with larger number
1817 * of strings. (Think VAR="a b"; echo $VAR).
1818 * This new list is allocated as a single malloc block.
1819 * NULL-terminated list of char* pointers is at the beginning of it,
1820 * followed by strings themself.
1821 * Caller can deallocate entire list by single free(list). */
1823 /* Store given string, finalizing the word and starting new one whenever
1824 * we encounter IFS char(s). This is used for expanding variable values.
1825 * End-of-string does NOT finalize word: think about 'echo -$VAR-' */
1826 static int expand_on_ifs(o_string
*output
, int n
, const char *str
)
1829 int word_len
= strcspn(str
, G
.ifs
);
1831 if (output
->o_escape
|| !output
->o_glob
)
1832 o_addQstr(output
, str
, word_len
);
1833 else /* protect backslashes against globbing up :) */
1834 o_addblock_duplicate_backslash(output
, str
, word_len
);
1837 if (!*str
) /* EOL - do not finalize word */
1839 o_addchr(output
, '\0');
1840 debug_print_list("expand_on_ifs", output
, n
);
1841 n
= o_save_ptr(output
, n
);
1842 str
+= strspn(str
, G
.ifs
); /* skip ifs chars */
1844 debug_print_list("expand_on_ifs[1]", output
, n
);
1848 /* Helper to expand $((...)) and heredoc body. These act as if
1849 * they are in double quotes, with the exception that they are not :).
1850 * Just the rules are similar: "expand only $var and `cmd`"
1852 * Returns malloced string.
1853 * As an optimization, we return NULL if expansion is not needed.
1855 static char *expand_pseudo_dquoted(const char *str
)
1858 struct in_str input
;
1859 o_string dest
= NULL_O_STRING
;
1861 if (strchr(str
, '$') == NULL
1862 #if ENABLE_HUSH_TICK
1863 && strchr(str
, '`') == NULL
1869 /* We need to expand. Example:
1870 * echo $(($a + `echo 1`)) $((1 + $((2)) ))
1872 setup_string_in_str(&input
, str
);
1873 parse_stream_dquoted(NULL
, &dest
, &input
, EOF
);
1874 //bb_error_msg("'%s' -> '%s'", str, dest.data);
1875 exp_str
= expand_string_to_string(dest
.data
);
1876 //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
1877 o_free_unsafe(&dest
);
1881 /* Expand all variable references in given string, adding words to list[]
1882 * at n, n+1,... positions. Return updated n (so that list[n] is next one
1883 * to be filled). This routine is extremely tricky: has to deal with
1884 * variables/parameters with whitespace, $* and $@, and constructs like
1885 * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
1886 static int expand_vars_to_list(o_string
*output
, int n
, char *arg
, char or_mask
)
1888 /* or_mask is either 0 (normal case) or 0x80
1889 * (expansion of right-hand side of assignment == 1-element expand.
1890 * It will also do no globbing, and thus we must not backslash-quote!) */
1892 char first_ch
, ored_ch
;
1900 debug_printf_expand("expand_vars_to_list: arg '%s'\n", arg
);
1901 debug_print_list("expand_vars_to_list", output
, n
);
1902 n
= o_save_ptr(output
, n
);
1903 debug_print_list("expand_vars_to_list[0]", output
, n
);
1905 while ((p
= strchr(arg
, SPECIAL_VAR_SYMBOL
)) != NULL
) {
1906 #if ENABLE_HUSH_TICK
1907 o_string subst_result
= NULL_O_STRING
;
1909 #if ENABLE_SH_MATH_SUPPORT
1910 char arith_buf
[sizeof(arith_t
)*3 + 2];
1912 o_addblock(output
, arg
, p
- arg
);
1913 debug_print_list("expand_vars_to_list[1]", output
, n
);
1915 p
= strchr(p
, SPECIAL_VAR_SYMBOL
);
1917 first_ch
= arg
[0] | or_mask
; /* forced to "quoted" if or_mask = 0x80 */
1918 /* "$@" is special. Even if quoted, it can still
1919 * expand to nothing (not even an empty string) */
1920 if ((first_ch
& 0x7f) != '@')
1921 ored_ch
|= first_ch
;
1924 switch (first_ch
& 0x7f) {
1925 /* Highest bit in first_ch indicates that var is double-quoted */
1927 val
= utoa(G
.root_pid
);
1929 case '!': /* bg pid */
1930 val
= G
.last_bg_pid
? utoa(G
.last_bg_pid
) : (char*)"";
1932 case '?': /* exitcode */
1933 val
= utoa(G
.last_exitcode
);
1935 case '#': /* argc */
1936 if (arg
[1] != SPECIAL_VAR_SYMBOL
)
1937 /* actually, it's a ${#var} */
1939 val
= utoa(G
.global_argc
? G
.global_argc
-1 : 0);
1944 if (!G
.global_argv
[i
])
1946 ored_ch
|= first_ch
; /* do it for "$@" _now_, when we know it's not empty */
1947 if (!(first_ch
& 0x80)) { /* unquoted $* or $@ */
1948 smallint sv
= output
->o_escape
;
1949 /* unquoted var's contents should be globbed, so don't escape */
1950 output
->o_escape
= 0;
1951 while (G
.global_argv
[i
]) {
1952 n
= expand_on_ifs(output
, n
, G
.global_argv
[i
]);
1953 debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i
, G
.global_argc
- 1);
1954 if (G
.global_argv
[i
++][0] && G
.global_argv
[i
]) {
1955 /* this argv[] is not empty and not last:
1956 * put terminating NUL, start new word */
1957 o_addchr(output
, '\0');
1958 debug_print_list("expand_vars_to_list[2]", output
, n
);
1959 n
= o_save_ptr(output
, n
);
1960 debug_print_list("expand_vars_to_list[3]", output
, n
);
1963 output
->o_escape
= sv
;
1965 /* If or_mask is nonzero, we handle assignment 'a=....$@.....'
1966 * and in this case should treat it like '$*' - see 'else...' below */
1967 if (first_ch
== ('@'|0x80) && !or_mask
) { /* quoted $@ */
1969 o_addQstr(output
, G
.global_argv
[i
], strlen(G
.global_argv
[i
]));
1970 if (++i
>= G
.global_argc
)
1972 o_addchr(output
, '\0');
1973 debug_print_list("expand_vars_to_list[4]", output
, n
);
1974 n
= o_save_ptr(output
, n
);
1976 } else { /* quoted $*: add as one word */
1978 o_addQstr(output
, G
.global_argv
[i
], strlen(G
.global_argv
[i
]));
1979 if (!G
.global_argv
[++i
])
1982 o_addchr(output
, G
.ifs
[0]);
1986 case SPECIAL_VAR_SYMBOL
: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
1987 /* "Empty variable", used to make "" etc to not disappear */
1991 #if ENABLE_HUSH_TICK
1992 case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
1995 //TODO: can we just stuff it into "output" directly?
1996 debug_printf_subst("SUBST '%s' first_ch %x\n", arg
, first_ch
);
1997 process_command_subs(&subst_result
, arg
);
1998 debug_printf_subst("SUBST RES '%s'\n", subst_result
.data
);
1999 val
= subst_result
.data
;
2002 #if ENABLE_SH_MATH_SUPPORT
2003 case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */
2004 arith_eval_hooks_t hooks
;
2009 arg
++; /* skip '+' */
2010 *p
= '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
2011 debug_printf_subst("ARITH '%s' first_ch %x\n", arg
, first_ch
);
2013 exp_str
= expand_pseudo_dquoted(arg
);
2014 hooks
.lookupvar
= get_local_var_value
;
2015 hooks
.setvar
= arith_set_local_var
;
2016 hooks
.endofname
= endofname
;
2017 res
= arith(exp_str
? exp_str
: arg
, &errcode
, &hooks
);
2021 const char *msg
= "error in arithmetic";
2024 msg
= "exponent less than 0";
2027 msg
= "divide by 0";
2030 msg
= "expression recursion loop detected";
2035 debug_printf_subst("ARITH RES '"arith_t_fmt
"'\n", res
);
2036 sprintf(arith_buf
, arith_t_fmt
, res
);
2041 default: /* <SPECIAL_VAR_SYMBOL>varname<SPECIAL_VAR_SYMBOL> */
2043 bool exp_len
= false;
2044 bool exp_null
= false;
2046 char exp_save
= exp_save
; /* for compiler */
2047 char exp_op
= exp_op
; /* for compiler */
2048 char *exp_word
= exp_word
; /* for compiler */
2052 arg
[0] = first_ch
& 0x7f;
2054 /* prepare for expansions */
2055 if (var
[0] == '#') {
2056 /* handle length expansion ${#var} */
2060 /* maybe handle parameter expansion */
2061 exp_off
= strcspn(var
, ":-=+?%#");
2065 exp_save
= var
[exp_off
];
2066 exp_null
= exp_save
== ':';
2067 exp_word
= var
+ exp_off
;
2070 exp_op
= *exp_word
++;
2071 var
[exp_off
] = '\0';
2075 /* lookup the variable in question */
2076 if (isdigit(var
[0])) {
2077 /* handle_dollar() should have vetted var for us */
2079 if (i
< G
.global_argc
)
2080 val
= G
.global_argv
[i
];
2081 /* else val remains NULL: $N with too big N */
2083 val
= get_local_var_value(var
);
2085 /* handle any expansions */
2087 debug_printf_expand("expand: length of '%s' = ", val
);
2088 val
= utoa(val
? strlen(val
) : 0);
2089 debug_printf_expand("%s\n", val
);
2090 } else if (exp_off
) {
2091 if (exp_op
== '%' || exp_op
== '#') {
2093 /* we need to do a pattern match */
2096 scan_t scan
= pick_scan(exp_op
, *exp_word
, &zero
);
2097 if (exp_op
== *exp_word
) /* ## or %% */
2099 val
= dyn_val
= xstrdup(val
);
2100 loc
= scan(dyn_val
, exp_word
, zero
);
2107 /* we need to do an expansion */
2108 int exp_test
= (!val
|| (exp_null
&& !val
[0]));
2110 exp_test
= !exp_test
;
2111 debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op
,
2112 exp_null
? "true" : "false", exp_test
);
2114 if (exp_op
== '?') {
2115 //TODO: how interactive bash aborts expansion mid-command?
2116 /* ${var?[error_msg_if_unset]} */
2117 /* ${var:?[error_msg_if_unset_or_null]} */
2118 /* mimic bash message */
2119 die_if_script("%s: %s",
2121 exp_word
[0] ? exp_word
: "parameter null or not set"
2127 if (exp_op
== '=') {
2128 /* ${var=[word]} or ${var:=[word]} */
2129 if (isdigit(var
[0]) || var
[0] == '#') {
2130 /* mimic bash message */
2131 die_if_script("$%s: cannot assign in this way", var
);
2134 char *new_var
= xasprintf("%s=%s", var
, val
);
2135 set_local_var(new_var
, -1, 0);
2141 var
[exp_off
] = exp_save
;
2145 #if ENABLE_HUSH_TICK
2148 if (!(first_ch
& 0x80)) { /* unquoted $VAR */
2149 debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val
, output
->o_escape
);
2151 /* unquoted var's contents should be globbed, so don't escape */
2152 smallint sv
= output
->o_escape
;
2153 output
->o_escape
= 0;
2154 n
= expand_on_ifs(output
, n
, val
);
2156 output
->o_escape
= sv
;
2158 } else { /* quoted $VAR, val will be appended below */
2159 debug_printf_expand("quoted '%s', output->o_escape:%d\n", val
, output
->o_escape
);
2162 } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
2164 o_addQstr(output
, val
, strlen(val
));
2168 /* Do the check to avoid writing to a const string */
2169 if (*p
!= SPECIAL_VAR_SYMBOL
)
2170 *p
= SPECIAL_VAR_SYMBOL
;
2172 #if ENABLE_HUSH_TICK
2173 o_free(&subst_result
);
2176 } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
2179 debug_print_list("expand_vars_to_list[a]", output
, n
);
2180 /* this part is literal, and it was already pre-quoted
2181 * if needed (much earlier), do not use o_addQstr here! */
2182 o_addstr_with_NUL(output
, arg
);
2183 debug_print_list("expand_vars_to_list[b]", output
, n
);
2184 } else if (output
->length
== o_get_last_ptr(output
, n
) /* expansion is empty */
2185 && !(ored_ch
& 0x80) /* and all vars were not quoted. */
2188 /* allow to reuse list[n] later without re-growth */
2189 output
->has_empty_slot
= 1;
2191 o_addchr(output
, '\0');
2196 static char **expand_variables(char **argv
, int or_mask
)
2201 o_string output
= NULL_O_STRING
;
2203 if (or_mask
& 0x100) {
2204 output
.o_escape
= 1; /* protect against globbing for "$var" */
2205 /* (unquoted $var will temporarily switch it off) */
2212 n
= expand_vars_to_list(&output
, n
, *v
, (char)or_mask
);
2215 debug_print_list("expand_variables", &output
, n
);
2217 /* output.data (malloced in one block) gets returned in "list" */
2218 list
= o_finalize_list(&output
, n
);
2219 debug_print_strings("expand_variables[1]", list
);
2223 static char **expand_strvec_to_strvec(char **argv
)
2225 return expand_variables(argv
, 0x100);
2228 /* Used for expansion of right hand of assignments */
2229 /* NB: should NOT do globbing! "export v=/bin/c*; env | grep ^v=" outputs
2231 static char *expand_string_to_string(const char *str
)
2233 char *argv
[2], **list
;
2235 argv
[0] = (char*)str
;
2237 list
= expand_variables(argv
, 0x80); /* 0x80: make one-element expansion */
2239 if (!list
[0] || list
[1])
2240 bb_error_msg_and_die("BUG in varexp2");
2241 /* actually, just move string 2*sizeof(char*) bytes back */
2242 overlapping_strcpy((char*)list
, list
[0]);
2243 debug_printf_expand("string_to_string='%s'\n", (char*)list
);
2247 /* Used for "eval" builtin */
2248 static char* expand_strvec_to_string(char **argv
)
2252 list
= expand_variables(argv
, 0x80);
2253 /* Convert all NULs to spaces */
2258 if (list
[n
-1] + strlen(list
[n
-1]) + 1 != list
[n
])
2259 bb_error_msg_and_die("BUG in varexp3");
2260 list
[n
][-1] = ' '; /* TODO: or to G.ifs[0]? */
2264 overlapping_strcpy((char*)list
, list
[0]);
2265 debug_printf_expand("strvec_to_string='%s'\n", (char*)list
);
2269 static char **expand_assignments(char **argv
, int count
)
2273 /* Expand assignments into one string each */
2274 for (i
= 0; i
< count
; i
++) {
2275 p
= add_string_to_strings(p
, expand_string_to_string(argv
[i
]));
2283 void re_execute_shell(const char *s
, char *argv0
, char **argv
);
2285 #define clean_up_after_re_execute() ((void)0)
2287 static void reset_traps_to_defaults(void)
2295 for (sig
= 0; sig
< NSIG
; sig
++) {
2299 G
.traps
[sig
] = NULL
;
2300 /* There is no signal for 0 (EXIT) */
2303 /* there was a trap handler, we are removing it
2304 * (if sig has non-DFL handling,
2305 * we don't need to do anything) */
2306 if (sig
< 32 && (G
.non_DFL_mask
& (1 << sig
)))
2308 sigdelset(&G
.blocked_set
, sig
);
2312 sigprocmask(SIG_SETMASK
, &G
.blocked_set
, NULL
);
2317 static void re_execute_shell(const char *s
, char *g_argv0
, char **g_argv
) NORETURN
;
2318 static void re_execute_shell(const char *s
, char *g_argv0
, char **g_argv
)
2320 char param_buf
[sizeof("-$%x:%x:%x:%x") + sizeof(unsigned) * 4];
2321 char *heredoc_argv
[4];
2322 struct variable
*cur
;
2323 #if ENABLE_HUSH_FUNCTIONS
2324 struct function
*funcp
;
2329 if (!g_argv0
) { /* heredoc */
2330 argv
= heredoc_argv
;
2331 argv
[0] = (char *) G
.argv0_for_re_execing
;
2332 argv
[1] = (char *) "-<";
2333 argv
[2] = (char *) s
;
2335 pp
= &argv
[3]; /* used as pointer to empty environment */
2339 sprintf(param_buf
, "-$%x:%x:%x" USE_HUSH_LOOPS(":%x")
2340 , (unsigned) G
.root_pid
2341 , (unsigned) G
.last_bg_pid
2342 , (unsigned) G
.last_exitcode
2343 USE_HUSH_LOOPS(, G
.depth_of_loop
)
2345 /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<depth> <vars...> <funcs...>
2346 * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL
2349 for (cur
= G
.top_var
; cur
; cur
= cur
->next
) {
2350 if (!cur
->flg_export
|| cur
->flg_read_only
)
2353 #if ENABLE_HUSH_FUNCTIONS
2354 for (funcp
= G
.top_func
; funcp
; funcp
= funcp
->next
)
2360 G
.argv_from_re_execing
= argv
= pp
= xzalloc(sizeof(argv
[0]) * cnt
);
2361 *pp
++ = (char *) G
.argv0_for_re_execing
;
2363 for (cur
= G
.top_var
; cur
; cur
= cur
->next
) {
2364 if (cur
->varstr
== hush_version_str
)
2366 if (cur
->flg_read_only
) {
2367 *pp
++ = (char *) "-R";
2368 *pp
++ = cur
->varstr
;
2369 } else if (!cur
->flg_export
) {
2370 *pp
++ = (char *) "-V";
2371 *pp
++ = cur
->varstr
;
2374 #if ENABLE_HUSH_FUNCTIONS
2375 for (funcp
= G
.top_func
; funcp
; funcp
= funcp
->next
) {
2376 *pp
++ = (char *) "-F";
2377 *pp
++ = funcp
->name
;
2378 *pp
++ = funcp
->body_as_string
;
2381 /* We can pass activated traps here. Say, -Tnn:trap_string
2383 * However, POSIX says that subshells reset signals with traps
2385 * I tested bash-3.2 and it not only does that with true subshells
2386 * of the form ( list ), but with any forked children shells.
2387 * I set trap "echo W" WINCH; and then tried:
2389 * { echo 1; sleep 20; echo 2; } &
2390 * while true; do echo 1; sleep 20; echo 2; break; done &
2391 * true | { echo 1; sleep 20; echo 2; } | cat
2393 * In all these cases sending SIGWINCH to the child shell
2394 * did not run the trap. If I add trap "echo V" WINCH;
2395 * _inside_ group (just before echo 1), it works.
2397 * I conclude it means we don't need to pass active traps here.
2398 * exec syscall below resets them to SIG_DFL for us.
2400 *pp
++ = (char *) "-c";
2405 /* *pp = NULL; - is already there */
2409 debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s
);
2410 sigprocmask(SIG_SETMASK
, &G
.inherited_set
, NULL
);
2411 execve(bb_busybox_exec_path
, argv
, pp
);
2412 /* Fallback. Useful for init=/bin/hush usage etc */
2413 if (argv
[0][0] == '/')
2414 execve(argv
[0], argv
, pp
);
2415 xfunc_error_retval
= 127;
2416 bb_error_msg_and_die("can't re-execute the shell");
2419 static void clean_up_after_re_execute(void)
2421 char **pp
= G
.argv_from_re_execing
;
2423 /* Must match re_execute_shell's allocations (if any) */
2425 G
.argv_from_re_execing
= NULL
;
2428 #endif /* !BB_MMU */
2431 static void setup_heredoc(struct redir_struct
*redir
)
2433 struct fd_pair pair
;
2436 /* the _body_ of heredoc (misleading field name) */
2437 const char *heredoc
= redir
->rd_filename
;
2441 if (!(redir
->rd_dup
& HEREDOC_QUOTED
)) {
2442 expanded
= expand_pseudo_dquoted(heredoc
);
2446 len
= strlen(heredoc
);
2448 close(redir
->rd_fd
); /* often saves dup2+close in xmove_fd */
2450 xmove_fd(pair
.rd
, redir
->rd_fd
);
2452 /* Try writing without forking. Newer kernels have
2453 * dynamically growing pipes. Must use non-blocking write! */
2456 written
= write(pair
.wr
, heredoc
, len
);
2467 ndelay_off(pair
.wr
);
2469 /* Okay, pipe buffer was not big enough */
2470 /* Note: we must not create a stray child (bastard? :)
2471 * for the unsuspecting parent process. Child creates a grandchild
2472 * and exits before parent execs the process which consumes heredoc
2473 * (that exec happens after we return from this function) */
2476 bb_perror_msg_and_die("vfork");
2479 pid
= BB_MMU
? fork() : vfork();
2481 bb_perror_msg_and_die(BB_MMU
? "fork" : "vfork");
2485 close(redir
->rd_fd
); /* read side of the pipe */
2487 full_write(pair
.wr
, heredoc
, len
); /* may loop or block */
2490 /* Delegate blocking writes to another process */
2491 disable_restore_tty_pgrp_on_exit();
2492 xmove_fd(pair
.wr
, STDOUT_FILENO
);
2493 re_execute_shell(heredoc
, NULL
, NULL
);
2497 enable_restore_tty_pgrp_on_exit();
2498 clean_up_after_re_execute();
2501 wait(NULL
); /* wait till child has died */
2504 /* squirrel != NULL means we squirrel away copies of stdin, stdout,
2505 * and stderr if they are redirected. */
2506 static int setup_redirects(struct command
*prog
, int squirrel
[])
2509 struct redir_struct
*redir
;
2511 for (redir
= prog
->redirects
; redir
; redir
= redir
->next
) {
2512 if (redir
->rd_type
== REDIRECT_HEREDOC2
) {
2513 /* rd_fd<<HERE case */
2514 if (squirrel
&& redir
->rd_fd
< 3) {
2515 squirrel
[redir
->rd_fd
] = dup(redir
->rd_fd
);
2517 /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
2519 debug_printf_parse("set heredoc '%s'\n",
2520 redir
->rd_filename
);
2521 setup_heredoc(redir
);
2525 if (redir
->rd_dup
== REDIRFD_TO_FILE
) {
2526 /* rd_fd<*>file case (<*> is <,>,>>,<>) */
2528 if (redir
->rd_filename
== NULL
) {
2529 /* Something went wrong in the parse.
2530 * Pretend it didn't happen */
2531 bb_error_msg("bug in redirect parse");
2534 mode
= redir_table
[redir
->rd_type
].mode
;
2535 p
= expand_string_to_string(redir
->rd_filename
);
2536 openfd
= open_or_warn(p
, mode
);
2539 /* this could get lost if stderr has been redirected, but
2540 * bash and ash both lose it as well (though zsh doesn't!) */
2541 //what the above comment tries to say?
2545 /* rd_fd<*>rd_dup or rd_fd<*>- cases */
2546 openfd
= redir
->rd_dup
;
2549 if (openfd
!= redir
->rd_fd
) {
2550 if (squirrel
&& redir
->rd_fd
< 3) {
2551 squirrel
[redir
->rd_fd
] = dup(redir
->rd_fd
);
2553 if (openfd
== REDIRFD_CLOSE
) {
2554 /* "n>-" means "close me" */
2555 close(redir
->rd_fd
);
2557 xdup2(openfd
, redir
->rd_fd
);
2558 if (redir
->rd_dup
== REDIRFD_TO_FILE
)
2566 static void restore_redirects(int squirrel
[])
2569 for (i
= 0; i
< 3; i
++) {
2572 /* We simply die on error */
2579 static void free_pipe_list(struct pipe
*head
);
2581 /* Return code is the exit status of the pipe */
2582 static void free_pipe(struct pipe
*pi
)
2585 struct command
*command
;
2586 struct redir_struct
*r
, *rnext
;
2589 if (pi
->stopped_cmds
> 0) /* why? */
2591 debug_printf_clean("run pipe: (pid %d)\n", getpid());
2592 for (i
= 0; i
< pi
->num_cmds
; i
++) {
2593 command
= &pi
->cmds
[i
];
2594 debug_printf_clean(" command %d:\n", i
);
2595 if (command
->argv
) {
2596 for (a
= 0, p
= command
->argv
; *p
; a
++, p
++) {
2597 debug_printf_clean(" argv[%d] = %s\n", a
, *p
);
2599 free_strings(command
->argv
);
2600 command
->argv
= NULL
;
2602 /* not "else if": on syntax error, we may have both! */
2603 if (command
->group
) {
2604 debug_printf_clean(" begin group (grp_type:%d)\n",
2606 free_pipe_list(command
->group
);
2607 debug_printf_clean(" end group\n");
2608 command
->group
= NULL
;
2610 /* else is crucial here.
2611 * If group != NULL, child_func is meaningless */
2612 #if ENABLE_HUSH_FUNCTIONS
2613 else if (command
->child_func
) {
2614 debug_printf_exec("cmd %p releases child func at %p\n", command
, command
->child_func
);
2615 command
->child_func
->parent_cmd
= NULL
;
2619 free(command
->group_as_string
);
2620 command
->group_as_string
= NULL
;
2622 for (r
= command
->redirects
; r
; r
= rnext
) {
2623 debug_printf_clean(" redirect %d%s",
2624 r
->rd_fd
, redir_table
[r
->rd_type
].descrip
);
2625 /* guard against the case >$FOO, where foo is unset or blank */
2626 if (r
->rd_filename
) {
2627 debug_printf_clean(" fname:'%s'\n", r
->rd_filename
);
2628 free(r
->rd_filename
);
2629 r
->rd_filename
= NULL
;
2631 debug_printf_clean(" rd_dup:%d\n", r
->rd_dup
);
2635 command
->redirects
= NULL
;
2637 free(pi
->cmds
); /* children are an array, they get freed all at once */
2645 static void free_pipe_list(struct pipe
*head
)
2647 struct pipe
*pi
, *next
;
2649 for (pi
= head
; pi
; pi
= next
) {
2651 debug_printf_clean(" pipe reserved word %d\n", pi
->res_word
);
2654 debug_printf_clean("pipe followup code %d\n", pi
->followup
);
2656 /*pi->next = NULL;*/
2662 static int run_list(struct pipe
*pi
);
2664 #define parse_stream(pstring, input, end_trigger) \
2665 parse_stream(input, end_trigger)
2667 static struct pipe
*parse_stream(char **pstring
,
2668 struct in_str
*input
,
2670 static void parse_and_run_string(const char *s
);
2673 static const struct built_in_command
* find_builtin(const char *name
)
2675 const struct built_in_command
*x
;
2676 for (x
= bltins
; x
!= &bltins
[ARRAY_SIZE(bltins
)]; x
++) {
2677 if (strcmp(name
, x
->cmd
) != 0)
2679 debug_printf_exec("found builtin '%s'\n", name
);
2685 #if ENABLE_HUSH_FUNCTIONS
2686 static const struct function
*find_function(const char *name
)
2688 const struct function
*funcp
= G
.top_func
;
2690 if (strcmp(name
, funcp
->name
) == 0) {
2693 funcp
= funcp
->next
;
2695 debug_printf_exec("found function '%s'\n", name
);
2699 /* Note: takes ownership on name ptr */
2700 static struct function
*new_function(char *name
)
2702 struct function
*funcp
;
2703 struct function
**funcpp
= &G
.top_func
;
2705 while ((funcp
= *funcpp
) != NULL
) {
2706 struct command
*cmd
;
2708 if (strcmp(funcp
->name
, name
) != 0) {
2709 funcpp
= &funcp
->next
;
2713 cmd
= funcp
->parent_cmd
;
2714 debug_printf_exec("func %p parent_cmd %p\n", funcp
, cmd
);
2716 debug_printf_exec("freeing & replacing function '%s'\n", funcp
->name
);
2718 /* Note: if !funcp->body, do not free body_as_string!
2719 * This is a special case of "-F name body" function:
2720 * body_as_string was not malloced! */
2722 free_pipe_list(funcp
->body
);
2724 free(funcp
->body_as_string
);
2728 debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp
->name
);
2729 cmd
->argv
[0] = funcp
->name
;
2730 cmd
->group
= funcp
->body
;
2732 cmd
->group_as_string
= funcp
->body_as_string
;
2737 debug_printf_exec("remembering new function '%s'\n", command
->argv
[0]);
2738 funcp
= *funcpp
= xzalloc(sizeof(*funcp
));
2739 /*funcp->next = NULL;*/
2745 static void exec_function(const struct function
*funcp
, char **argv
) NORETURN
;
2746 static void exec_function(const struct function
*funcp
, char **argv
)
2751 argv
[0] = G
.global_argv
[0];
2752 G
.global_argv
= argv
;
2756 /* On MMU, funcp->body is always non-NULL */
2757 n
= run_list(funcp
->body
);
2761 re_execute_shell(funcp
->body_as_string
, G
.global_argv
[0], argv
+ 1);
2765 static int run_function(const struct function
*funcp
, char **argv
)
2770 smallint sv_g_malloced
;
2775 sv_g_malloced
= G
.global_args_malloced
;
2776 sv_g_argc
= G
.global_argc
;
2777 sv_g_argv
= G
.global_argv
;
2784 argv
[0] = G
.global_argv
[0]; /* retain $0 */
2785 G
.global_args_malloced
= 0;
2787 G
.global_argv
= argv
;
2789 /* On MMU, funcp->body is always non-NULL */
2792 /* Function defined by -F */
2793 parse_and_run_string(funcp
->body_as_string
);
2794 n
= G
.last_exitcode
;
2798 n
= run_list(funcp
->body
);
2801 if (G
.global_args_malloced
) {
2802 /* function ran "set -- arg1 arg2 ..." */
2806 free(G
.global_argv
);
2810 G
.global_args_malloced
= sv_g_malloced
;
2811 G
.global_argc
= sv_g_argc
;
2812 G
.global_argv
= sv_g_argv
;
2820 #define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
2821 pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
2822 #define pseudo_exec(nommu_save, command, argv_expanded) \
2823 pseudo_exec(command, argv_expanded)
2826 /* Called after [v]fork() in run_pipe, or from builtin_exec.
2828 * XXX no exit() here. If you don't exec, use _exit instead.
2829 * The at_exit handlers apparently confuse the calling process,
2830 * in particular stdin handling. Not sure why? -- because of vfork! (vda) */
2831 static void pseudo_exec_argv(nommu_save_t
*nommu_save
,
2832 char **argv
, int assignment_cnt
,
2833 char **argv_expanded
) NORETURN
;
2834 static void pseudo_exec_argv(nommu_save_t
*nommu_save
,
2835 char **argv
, int assignment_cnt
,
2836 char **argv_expanded
)
2840 /* Case when we are here: ... | var=val | ... */
2841 if (!argv
[assignment_cnt
])
2842 _exit(EXIT_SUCCESS
);
2844 new_env
= expand_assignments(argv
, assignment_cnt
);
2846 putenv_all(new_env
);
2847 free(new_env
); /* optional */
2849 nommu_save
->new_env
= new_env
;
2850 nommu_save
->old_env
= putenv_all_and_save_old(new_env
);
2852 if (argv_expanded
) {
2853 argv
= argv_expanded
;
2855 argv
= expand_strvec_to_strvec(argv
+ assignment_cnt
);
2857 nommu_save
->argv
= argv
;
2861 #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
2862 if (strchr(argv
[0], '/') != NULL
)
2866 /* On NOMMU, we must never block!
2867 * Example: { sleep 99999 | read line } & echo Ok
2868 * read builtin will block on read syscall, leaving parent blocked
2869 * in vfork. Therefore we can't do this:
2872 /* Check if the command matches any of the builtins.
2873 * Depending on context, this might be redundant. But it's
2874 * easier to waste a few CPU cycles than it is to figure out
2875 * if this is one of those cases.
2879 const struct built_in_command
*x
= find_builtin(argv
[0]);
2881 rcode
= x
->function(argv
);
2887 #if ENABLE_HUSH_FUNCTIONS
2888 /* Check if the command matches any functions */
2890 const struct function
*funcp
= find_function(argv
[0]);
2892 exec_function(funcp
, argv
);
2897 #if ENABLE_FEATURE_SH_STANDALONE
2898 /* Check if the command matches any busybox applets */
2900 int a
= find_applet_by_name(argv
[0]);
2902 # if BB_MMU /* see above why on NOMMU it is not allowed */
2903 if (APPLET_IS_NOEXEC(a
)) {
2904 debug_printf_exec("running applet '%s'\n", argv
[0]);
2905 run_applet_no_and_exit(a
, argv
);
2908 /* Re-exec ourselves */
2909 debug_printf_exec("re-execing applet '%s'\n", argv
[0]);
2910 sigprocmask(SIG_SETMASK
, &G
.inherited_set
, NULL
);
2911 execv(bb_busybox_exec_path
, argv
);
2912 /* If they called chroot or otherwise made the binary no longer
2913 * executable, fall through */
2918 #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
2921 debug_printf_exec("execing '%s'\n", argv
[0]);
2922 sigprocmask(SIG_SETMASK
, &G
.inherited_set
, NULL
);
2923 execvp(argv
[0], argv
);
2924 bb_perror_msg("can't exec '%s'", argv
[0]);
2925 _exit(EXIT_FAILURE
);
2928 /* Called after [v]fork() in run_pipe
2930 static void pseudo_exec(nommu_save_t
*nommu_save
,
2931 struct command
*command
,
2932 char **argv_expanded
) NORETURN
;
2933 static void pseudo_exec(nommu_save_t
*nommu_save
,
2934 struct command
*command
,
2935 char **argv_expanded
)
2937 if (command
->argv
) {
2938 pseudo_exec_argv(nommu_save
, command
->argv
,
2939 command
->assignment_cnt
, argv_expanded
);
2942 if (command
->group
) {
2943 /* Cases when we are here:
2946 * ... | ( list ) | ...
2947 * ... | { list } | ...
2951 debug_printf_exec("pseudo_exec: run_list\n");
2952 reset_traps_to_defaults();
2953 rcode
= run_list(command
->group
);
2954 /* OK to leak memory by not calling free_pipe_list,
2955 * since this process is about to exit */
2958 re_execute_shell(command
->group_as_string
,
2964 /* Case when we are here: ... | >file */
2965 debug_printf_exec("pseudo_exec'ed null command\n");
2966 _exit(EXIT_SUCCESS
);
2970 static const char *get_cmdtext(struct pipe
*pi
)
2976 /* This is subtle. ->cmdtext is created only on first backgrounding.
2977 * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
2978 * On subsequent bg argv is trashed, but we won't use it */
2981 argv
= pi
->cmds
[0].argv
;
2982 if (!argv
|| !argv
[0]) {
2983 pi
->cmdtext
= xzalloc(1);
2988 do len
+= strlen(*argv
) + 1; while (*++argv
);
2989 pi
->cmdtext
= p
= xmalloc(len
);
2990 argv
= pi
->cmds
[0].argv
;
2992 len
= strlen(*argv
);
2993 memcpy(p
, *argv
, len
);
3001 static void insert_bg_job(struct pipe
*pi
)
3003 struct pipe
*thejob
;
3006 /* Linear search for the ID of the job to use */
3008 for (thejob
= G
.job_list
; thejob
; thejob
= thejob
->next
)
3009 if (thejob
->jobid
>= pi
->jobid
)
3010 pi
->jobid
= thejob
->jobid
+ 1;
3012 /* Add thejob to the list of running jobs */
3014 thejob
= G
.job_list
= xmalloc(sizeof(*thejob
));
3016 for (thejob
= G
.job_list
; thejob
->next
; thejob
= thejob
->next
)
3018 thejob
->next
= xmalloc(sizeof(*thejob
));
3019 thejob
= thejob
->next
;
3022 /* Physically copy the struct job */
3023 memcpy(thejob
, pi
, sizeof(struct pipe
));
3024 thejob
->cmds
= xzalloc(sizeof(pi
->cmds
[0]) * pi
->num_cmds
);
3025 /* We cannot copy entire pi->cmds[] vector! Double free()s will happen */
3026 for (i
= 0; i
< pi
->num_cmds
; i
++) {
3027 // TODO: do we really need to have so many fields which are just dead weight
3028 // at execution stage?
3029 thejob
->cmds
[i
].pid
= pi
->cmds
[i
].pid
;
3030 /* all other fields are not used and stay zero */
3032 thejob
->next
= NULL
;
3033 thejob
->cmdtext
= xstrdup(get_cmdtext(pi
));
3035 /* We don't wait for background thejobs to return -- append it
3036 to the list of backgrounded thejobs and leave it alone */
3037 if (G_interactive_fd
)
3038 printf("[%d] %d %s\n", thejob
->jobid
, thejob
->cmds
[0].pid
, thejob
->cmdtext
);
3039 G
.last_bg_pid
= thejob
->cmds
[0].pid
;
3040 G
.last_jobid
= thejob
->jobid
;
3043 static void remove_bg_job(struct pipe
*pi
)
3045 struct pipe
*prev_pipe
;
3047 if (pi
== G
.job_list
) {
3048 G
.job_list
= pi
->next
;
3050 prev_pipe
= G
.job_list
;
3051 while (prev_pipe
->next
!= pi
)
3052 prev_pipe
= prev_pipe
->next
;
3053 prev_pipe
->next
= pi
->next
;
3056 G
.last_jobid
= G
.job_list
->jobid
;
3061 /* Remove a backgrounded job */
3062 static void delete_finished_bg_job(struct pipe
*pi
)
3065 pi
->stopped_cmds
= 0;
3071 /* Check to see if any processes have exited -- if they
3072 * have, figure out why and see if a job has completed */
3073 static int checkjobs(struct pipe
* fg_pipe
)
3083 debug_printf_jobs("checkjobs %p\n", fg_pipe
);
3086 // if (G.handled_SIGCHLD == G.count_SIGCHLD)
3087 // /* avoid doing syscall, nothing there anyway */
3090 attributes
= WUNTRACED
;
3091 if (fg_pipe
== NULL
)
3092 attributes
|= WNOHANG
;
3094 /* Do we do this right?
3095 * bash-3.00# sleep 20 | false
3097 * [3]+ Stopped sleep 20 | false
3098 * bash-3.00# echo $?
3099 * 1 <========== bg pipe is not fully done, but exitcode is already known!
3102 //FIXME: non-interactive bash does not continue even if all processes in fg pipe
3103 //are stopped. Testcase: "cat | cat" in a script (not on command line)
3104 // + killall -STOP cat
3111 // i = G.count_SIGCHLD;
3112 childpid
= waitpid(-1, &status
, attributes
);
3113 if (childpid
<= 0) {
3114 if (childpid
&& errno
!= ECHILD
)
3115 bb_perror_msg("waitpid");
3116 // else /* Until next SIGCHLD, waitpid's are useless */
3117 // G.handled_SIGCHLD = i;
3120 dead
= WIFEXITED(status
) || WIFSIGNALED(status
);
3123 if (WIFSTOPPED(status
))
3124 debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
3125 childpid
, WSTOPSIG(status
), WEXITSTATUS(status
));
3126 if (WIFSIGNALED(status
))
3127 debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
3128 childpid
, WTERMSIG(status
), WEXITSTATUS(status
));
3129 if (WIFEXITED(status
))
3130 debug_printf_jobs("pid %d exited, exitcode %d\n",
3131 childpid
, WEXITSTATUS(status
));
3133 /* Were we asked to wait for fg pipe? */
3135 for (i
= 0; i
< fg_pipe
->num_cmds
; i
++) {
3136 debug_printf_jobs("check pid %d\n", fg_pipe
->cmds
[i
].pid
);
3137 if (fg_pipe
->cmds
[i
].pid
!= childpid
)
3139 /* printf("process %d exit %d\n", i, WEXITSTATUS(status)); */
3141 fg_pipe
->cmds
[i
].pid
= 0;
3142 fg_pipe
->alive_cmds
--;
3143 if (i
== fg_pipe
->num_cmds
- 1) {
3144 /* last process gives overall exitstatus */
3145 rcode
= WEXITSTATUS(status
);
3146 IF_HAS_KEYWORDS(if (fg_pipe
->pi_inverted
) rcode
= !rcode
;)
3149 fg_pipe
->cmds
[i
].is_stopped
= 1;
3150 fg_pipe
->stopped_cmds
++;
3152 debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
3153 fg_pipe
->alive_cmds
, fg_pipe
->stopped_cmds
);
3154 if (fg_pipe
->alive_cmds
- fg_pipe
->stopped_cmds
<= 0) {
3155 /* All processes in fg pipe have exited/stopped */
3157 if (fg_pipe
->alive_cmds
)
3158 insert_bg_job(fg_pipe
);
3162 /* There are still running processes in the fg pipe */
3163 goto wait_more
; /* do waitpid again */
3165 /* it wasnt fg_pipe, look for process in bg pipes */
3169 /* We asked to wait for bg or orphaned children */
3170 /* No need to remember exitcode in this case */
3171 for (pi
= G
.job_list
; pi
; pi
= pi
->next
) {
3172 for (i
= 0; i
< pi
->num_cmds
; i
++) {
3173 if (pi
->cmds
[i
].pid
== childpid
)
3174 goto found_pi_and_prognum
;
3177 /* Happens when shell is used as init process (init=/bin/sh) */
3178 debug_printf("checkjobs: pid %d was not in our list!\n", childpid
);
3179 continue; /* do waitpid again */
3181 found_pi_and_prognum
:
3184 pi
->cmds
[i
].pid
= 0;
3186 if (!pi
->alive_cmds
) {
3187 if (G_interactive_fd
)
3188 printf(JOB_STATUS_FORMAT
, pi
->jobid
,
3189 "Done", pi
->cmdtext
);
3190 delete_finished_bg_job(pi
);
3194 pi
->cmds
[i
].is_stopped
= 1;
3198 } /* while (waitpid succeeds)... */
3204 static int checkjobs_and_fg_shell(struct pipe
* fg_pipe
)
3207 int rcode
= checkjobs(fg_pipe
);
3208 /* Job finished, move the shell to the foreground */
3209 p
= getpgid(0); /* pgid of our process */
3210 debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p
);
3211 tcsetpgrp(G_interactive_fd
, p
);
3216 /* Start all the jobs, but don't wait for anything to finish.
3219 * Return code is normally -1, when the caller has to wait for children
3220 * to finish to determine the exit status of the pipe. If the pipe
3221 * is a simple builtin command, however, the action is done by the
3222 * time run_pipe returns, and the exit code is provided as the
3225 * Returns -1 only if started some children. IOW: we have to
3226 * mask out retvals of builtins etc with 0xff!
3228 * The only case when we do not need to [v]fork is when the pipe
3229 * is single, non-backgrounded, non-subshell command. Examples:
3230 * cmd ; ... { list } ; ...
3231 * cmd && ... { list } && ...
3232 * cmd || ... { list } || ...
3233 * If it is, then we can run cmd as a builtin, NOFORK [do we do this?],
3234 * or (if SH_STANDALONE) an applet, and we can run the { list }
3235 * with run_list(). If it isn't one of these, we fork and exec cmd.
3237 * Cases when we must fork:
3238 * non-single: cmd | cmd
3239 * backgrounded: cmd & { list } &
3240 * subshell: ( list ) [&]
3242 static int run_pipe(struct pipe
*pi
)
3244 static const char *const null_ptr
= NULL
;
3247 int pipefds
[2]; /* pipefds[0] is for reading */
3248 struct command
*command
;
3249 char **argv_expanded
;
3252 /* it is not always needed, but we aim to smaller code */
3253 int squirrel
[] = { -1, -1, -1 };
3256 debug_printf_exec("run_pipe start: members:%d\n", pi
->num_cmds
);
3259 USE_HUSH_JOB(pi
->pgrp
= -1;)
3260 pi
->stopped_cmds
= 0;
3261 command
= &(pi
->cmds
[0]);
3262 argv_expanded
= NULL
;
3264 if (pi
->num_cmds
!= 1
3265 || pi
->followup
== PIPE_BG
3266 || command
->grp_type
== GRP_SUBSHELL
3273 debug_printf_exec(": group:%p argv:'%s'\n",
3274 command
->group
, command
->argv
? command
->argv
[0] : "NONE");
3276 if (command
->group
) {
3277 #if ENABLE_HUSH_FUNCTIONS
3278 if (command
->grp_type
== GRP_FUNCTION
) {
3279 /* "executing" func () { list } */
3280 struct function
*funcp
;
3282 funcp
= new_function(command
->argv
[0]);
3283 /* funcp->name is already set to argv[0] */
3284 funcp
->body
= command
->group
;
3286 funcp
->body_as_string
= command
->group_as_string
;
3287 command
->group_as_string
= NULL
;
3289 command
->group
= NULL
;
3290 command
->argv
[0] = NULL
;
3291 debug_printf_exec("cmd %p has child func at %p\n", command
, funcp
);
3292 funcp
->parent_cmd
= command
;
3293 command
->child_func
= funcp
;
3295 debug_printf_exec("run_pipe: return EXIT_SUCCESS\n");
3297 return EXIT_SUCCESS
;
3301 debug_printf("non-subshell group\n");
3302 rcode
= 1; /* exitcode if redir failed */
3303 if (setup_redirects(command
, squirrel
) == 0) {
3304 debug_printf_exec(": run_list\n");
3305 rcode
= run_list(command
->group
) & 0xff;
3307 restore_redirects(squirrel
);
3308 IF_HAS_KEYWORDS(if (pi
->pi_inverted
) rcode
= !rcode
;)
3310 debug_printf_exec("run_pipe: return %d\n", rcode
);
3314 argv
= command
->argv
? command
->argv
: (char **) &null_ptr
;
3316 const struct built_in_command
*x
;
3317 #if ENABLE_HUSH_FUNCTIONS
3318 const struct function
*funcp
;
3322 char **new_env
= NULL
;
3323 char **old_env
= NULL
;
3325 if (argv
[command
->assignment_cnt
] == NULL
) {
3326 /* Assignments, but no command */
3327 /* Ensure redirects take effect. Try "a=t >file" */
3328 rcode
= setup_redirects(command
, squirrel
);
3329 restore_redirects(squirrel
);
3330 /* Set shell variables */
3332 p
= expand_string_to_string(*argv
);
3333 debug_printf_exec("set shell var:'%s'->'%s'\n",
3335 set_local_var(p
, 0, 0);
3338 /* Do we need to flag set_local_var() errors?
3339 * "assignment to readonly var" and "putenv error"
3341 IF_HAS_KEYWORDS(if (pi
->pi_inverted
) rcode
= !rcode
;)
3343 debug_printf_exec("run_pipe: return %d\n", rcode
);
3347 /* Expand the rest into (possibly) many strings each */
3348 argv_expanded
= expand_strvec_to_strvec(argv
+ command
->assignment_cnt
);
3350 x
= find_builtin(argv_expanded
[0]);
3351 #if ENABLE_HUSH_FUNCTIONS
3354 funcp
= find_function(argv_expanded
[0]);
3358 if (x
->function
== builtin_exec
&& argv_expanded
[1] == NULL
) {
3359 debug_printf("exec with redirects only\n");
3360 rcode
= setup_redirects(command
, NULL
);
3361 goto clean_up_and_ret1
;
3364 /* XXX setup_redirects acts on file descriptors, not FILEs.
3365 * This is perfect for work that comes after exec().
3366 * Is it really safe for inline use? Experimentally,
3367 * things seem to work with glibc. */
3368 rcode
= setup_redirects(command
, squirrel
);
3370 new_env
= expand_assignments(argv
, command
->assignment_cnt
);
3371 old_env
= putenv_all_and_save_old(new_env
);
3373 debug_printf_exec(": builtin '%s' '%s'...\n",
3374 x
->cmd
, argv_expanded
[1]);
3375 rcode
= x
->function(argv_expanded
) & 0xff;
3377 #if ENABLE_HUSH_FUNCTIONS
3379 debug_printf_exec(": function '%s' '%s'...\n",
3380 funcp
->name
, argv_expanded
[1]);
3381 rcode
= run_function(funcp
, argv_expanded
) & 0xff;
3385 #if ENABLE_FEATURE_SH_STANDALONE
3388 restore_redirects(squirrel
);
3389 free_strings_and_unsetenv(new_env
, 1);
3390 putenv_all(old_env
);
3391 /* Free the pointers, but the strings themselves
3392 * are in environ now, don't use free_strings! */
3395 free(argv_expanded
);
3396 IF_HAS_KEYWORDS(if (pi
->pi_inverted
) rcode
= !rcode
;)
3398 debug_printf_exec("run_pipe return %d\n", rcode
);
3402 #if ENABLE_FEATURE_SH_STANDALONE
3403 i
= find_applet_by_name(argv_expanded
[0]);
3404 if (i
>= 0 && APPLET_IS_NOFORK(i
)) {
3405 rcode
= setup_redirects(command
, squirrel
);
3407 save_nofork_data(&G
.nofork_save
);
3408 new_env
= expand_assignments(argv
, command
->assignment_cnt
);
3409 old_env
= putenv_all_and_save_old(new_env
);
3410 debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
3411 argv_expanded
[0], argv_expanded
[1]);
3412 rcode
= run_nofork_applet_prime(&G
.nofork_save
, i
, argv_expanded
);
3414 goto clean_up_and_ret
;
3417 /* It is neither builtin nor applet. We must fork. */
3421 /* NB: argv_expanded may already be created, and that
3422 * might include `cmd` runs! Do not rerun it! We *must*
3423 * use argv_expanded if it's non-NULL */
3425 /* Going to fork a child per each pipe member */
3429 for (i
= 0; i
< pi
->num_cmds
; i
++) {
3431 volatile nommu_save_t nommu_save
;
3432 nommu_save
.new_env
= NULL
;
3433 nommu_save
.old_env
= NULL
;
3434 nommu_save
.argv
= NULL
;
3436 command
= &(pi
->cmds
[i
]);
3437 if (command
->argv
) {
3438 debug_printf_exec(": pipe member '%s' '%s'...\n",
3439 command
->argv
[0], command
->argv
[1]);
3441 debug_printf_exec(": pipe member with no argv\n");
3444 /* pipes are inserted between pairs of commands */
3447 if ((i
+ 1) < pi
->num_cmds
)
3450 command
->pid
= BB_MMU
? fork() : vfork();
3451 if (!command
->pid
) { /* child */
3453 disable_restore_tty_pgrp_on_exit();
3455 /* Every child adds itself to new process group
3456 * with pgid == pid_of_first_child_in_pipe */
3457 if (G
.run_list_level
== 1 && G_interactive_fd
) {
3460 if (pgrp
< 0) /* true for 1st process only */
3462 if (setpgid(0, pgrp
) == 0 && pi
->followup
!= PIPE_BG
) {
3463 /* We do it in *every* child, not just first,
3465 tcsetpgrp(G_interactive_fd
, pgrp
);
3469 xmove_fd(nextin
, 0);
3470 xmove_fd(pipefds
[1], 1); /* write end */
3472 close(pipefds
[0]); /* read end */
3473 /* Like bash, explicit redirects override pipes,
3474 * and the pipe fd is available for dup'ing. */
3475 if (setup_redirects(command
, NULL
))
3478 /* Restore default handlers just prior to exec */
3479 /*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */
3481 /* Stores to nommu_save list of env vars putenv'ed
3482 * (NOMMU, on MMU we don't need that) */
3483 /* cast away volatility... */
3484 pseudo_exec((nommu_save_t
*) &nommu_save
, command
, argv_expanded
);
3485 /* pseudo_exec() does not return */
3488 /* parent or error */
3489 enable_restore_tty_pgrp_on_exit();
3491 /* Clean up after vforked child */
3492 clean_up_after_re_execute();
3493 free(nommu_save
.argv
);
3494 free_strings_and_unsetenv(nommu_save
.new_env
, 1);
3495 putenv_all(nommu_save
.old_env
);
3496 /* Free the pointers, but the strings themselves
3497 * are in environ now, don't use free_strings! */
3498 free(nommu_save
.old_env
);
3500 free(argv_expanded
);
3501 argv_expanded
= NULL
;
3502 if (command
->pid
< 0) { /* [v]fork failed */
3503 /* Clearly indicate, was it fork or vfork */
3504 bb_perror_msg(BB_MMU
? "fork" : "vfork");
3508 /* Second and next children need to know pid of first one */
3510 pi
->pgrp
= command
->pid
;
3516 if ((i
+ 1) < pi
->num_cmds
)
3517 close(pipefds
[1]); /* write end */
3518 /* Pass read (output) pipe end to next iteration */
3519 nextin
= pipefds
[0];
3522 if (!pi
->alive_cmds
) {
3524 debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
3529 debug_printf_exec("run_pipe return -1 (%u children started)\n", pi
->alive_cmds
);
3533 #ifndef debug_print_tree
3534 static void debug_print_tree(struct pipe
*pi
, int lvl
)
3536 static const char *const PIPE
[] = {
3542 static const char *RES
[] = {
3543 [RES_NONE
] = "NONE" ,
3546 [RES_THEN
] = "THEN" ,
3547 [RES_ELIF
] = "ELIF" ,
3548 [RES_ELSE
] = "ELSE" ,
3551 #if ENABLE_HUSH_LOOPS
3552 [RES_FOR
] = "FOR" ,
3553 [RES_WHILE
] = "WHILE",
3554 [RES_UNTIL
] = "UNTIL",
3556 [RES_DONE
] = "DONE" ,
3558 #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
3561 #if ENABLE_HUSH_CASE
3562 [RES_CASE
] = "CASE" ,
3563 [RES_MATCH
] = "MATCH",
3564 [RES_CASEI
] = "CASEI",
3565 [RES_ESAC
] = "ESAC" ,
3567 [RES_XXXX
] = "XXXX" ,
3568 [RES_SNTX
] = "SNTX" ,
3570 static const char *const GRPTYPE
[] = {
3573 #if ENABLE_HUSH_FUNCTIONS
3582 fprintf(stderr
, "%*spipe %d res_word=%s followup=%d %s\n", lvl
*2, "",
3583 pin
, RES
[pi
->res_word
], pi
->followup
, PIPE
[pi
->followup
]);
3585 while (prn
< pi
->num_cmds
) {
3586 struct command
*command
= &pi
->cmds
[prn
];
3587 char **argv
= command
->argv
;
3589 fprintf(stderr
, "%*s cmd %d assignment_cnt:%d",
3591 command
->assignment_cnt
);
3592 if (command
->group
) {
3593 fprintf(stderr
, " group %s: (argv=%p)\n",
3594 GRPTYPE
[command
->grp_type
],
3596 debug_print_tree(command
->group
, lvl
+1);
3600 if (argv
) while (*argv
) {
3601 fprintf(stderr
, " '%s'", *argv
);
3604 fprintf(stderr
, "\n");
3613 /* NB: called by pseudo_exec, and therefore must not modify any
3614 * global data until exec/_exit (we can be a child after vfork!) */
3615 static int run_list(struct pipe
*pi
)
3617 #if ENABLE_HUSH_CASE
3618 char *case_word
= NULL
;
3620 #if ENABLE_HUSH_LOOPS
3621 struct pipe
*loop_top
= NULL
;
3622 char *for_varname
= NULL
;
3623 char **for_lcur
= NULL
;
3624 char **for_list
= NULL
;
3626 smallint last_followup
;
3628 #if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
3629 smalluint cond_code
= 0;
3631 enum { cond_code
= 0 };
3634 smallint rword
; /* enum reserved_style */
3635 smallint last_rword
; /* ditto */
3638 debug_printf_exec("run_list start lvl %d\n", G
.run_list_level
+ 1);
3641 #if ENABLE_HUSH_LOOPS
3642 /* Check syntax for "for" */
3643 for (struct pipe
*cpipe
= pi
; cpipe
; cpipe
= cpipe
->next
) {
3644 if (cpipe
->res_word
!= RES_FOR
&& cpipe
->res_word
!= RES_IN
)
3646 /* current word is FOR or IN (BOLD in comments below) */
3647 if (cpipe
->next
== NULL
) {
3648 syntax_error("malformed for");
3650 debug_printf_exec("run_list lvl %d return 1\n", G
.run_list_level
);
3653 /* "FOR v; do ..." and "for v IN a b; do..." are ok */
3654 if (cpipe
->next
->res_word
== RES_DO
)
3656 /* next word is not "do". It must be "in" then ("FOR v in ...") */
3657 if (cpipe
->res_word
== RES_IN
/* "for v IN a b; not_do..."? */
3658 || cpipe
->next
->res_word
!= RES_IN
/* FOR v not_do_and_not_in..."? */
3660 syntax_error("malformed for");
3662 debug_printf_exec("run_list lvl %d return 1\n", G
.run_list_level
);
3668 /* Past this point, all code paths should jump to ret: label
3669 * in order to return, no direct "return" statements please.
3670 * This helps to ensure that no memory is leaked. */
3672 ////TODO: ctrl-Z handling needs re-thinking and re-testing
3675 /* Example of nested list: "while true; do { sleep 1 | exit 2; } done".
3676 * We are saving state before entering outermost list ("while...done")
3677 * so that ctrl-Z will correctly background _entire_ outermost list,
3678 * not just a part of it (like "sleep 1 | exit 2") */
3679 if (++G
.run_list_level
== 1 && G_interactive_fd
) {
3680 if (sigsetjmp(G
.toplevel_jb
, 1)) {
3681 /* ctrl-Z forked and we are parent; or ctrl-C.
3682 * Sighandler has longjmped us here */
3683 signal(SIGINT
, SIG_IGN
);
3684 signal(SIGTSTP
, SIG_IGN
);
3685 /* Restore level (we can be coming from deep inside
3687 G
.run_list_level
= 1;
3688 #if ENABLE_FEATURE_SH_STANDALONE
3689 if (G
.nofork_save
.saved
) { /* if save area is valid */
3690 debug_printf_jobs("exiting nofork early\n");
3691 restore_nofork_data(&G
.nofork_save
);
3694 //// if (G.ctrl_z_flag) {
3695 //// /* ctrl-Z has forked and stored pid of the child in pi->pid.
3696 //// * Remember this child as background job */
3697 //// insert_bg_job(pi);
3699 /* ctrl-C. We just stop doing whatever we were doing */
3702 USE_HUSH_LOOPS(loop_top
= NULL
;)
3703 USE_HUSH_LOOPS(G
.depth_of_loop
= 0;)
3707 //// /* ctrl-Z handler will store pid etc in pi */
3708 //// G.toplevel_list = pi;
3709 //// G.ctrl_z_flag = 0;
3710 #if ENABLE_FEATURE_SH_STANDALONE
3711 G
.nofork_save
.saved
= 0; /* in case we will run a nofork later */
3713 //// signal_SA_RESTART_empty_mask(SIGTSTP, handler_ctrl_z);
3714 //// signal(SIGINT, handler_ctrl_c);
3720 last_rword
= RES_XXXX
;
3722 last_followup
= PIPE_SEQ
;
3723 rcode
= G
.last_exitcode
;
3725 /* Go through list of pipes, (maybe) executing them. */
3726 for (; pi
; pi
= USE_HUSH_LOOPS(rword
== RES_DONE
? loop_top
: ) pi
->next
) {
3730 IF_HAS_KEYWORDS(rword
= pi
->res_word
;)
3731 debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
3732 rword
, cond_code
, last_rword
);
3733 #if ENABLE_HUSH_LOOPS
3734 if ((rword
== RES_WHILE
|| rword
== RES_UNTIL
|| rword
== RES_FOR
)
3735 && loop_top
== NULL
/* avoid bumping G.depth_of_loop twice */
3737 /* start of a loop: remember where loop starts */
3742 /* Still in the same "if...", "then..." or "do..." branch? */
3743 if (IF_HAS_KEYWORDS(rword
== last_rword
&&) 1) {
3744 if ((rcode
== 0 && last_followup
== PIPE_OR
)
3745 || (rcode
!= 0 && last_followup
== PIPE_AND
)
3747 /* It is "<true> || CMD" or "<false> && CMD"
3748 * and we should not execute CMD */
3749 debug_printf_exec("skipped cmd because of || or &&\n");
3750 last_followup
= pi
->followup
;
3754 last_followup
= pi
->followup
;
3755 IF_HAS_KEYWORDS(last_rword
= rword
;)
3758 if (rword
== RES_THEN
) {
3759 /* if false; then ... fi has exitcode 0! */
3760 G
.last_exitcode
= rcode
= EXIT_SUCCESS
;
3761 /* "if <false> THEN cmd": skip cmd */
3765 if (rword
== RES_ELSE
|| rword
== RES_ELIF
) {
3766 /* "if <true> then ... ELSE/ELIF cmd":
3767 * skip cmd and all following ones */
3772 #if ENABLE_HUSH_LOOPS
3773 if (rword
== RES_FOR
) { /* && pi->num_cmds - always == 1 */
3775 /* first loop through for */
3777 static const char encoded_dollar_at
[] ALIGN1
= {
3778 SPECIAL_VAR_SYMBOL
, '@' | 0x80, SPECIAL_VAR_SYMBOL
, '\0'
3779 }; /* encoded representation of "$@" */
3780 static const char *const encoded_dollar_at_argv
[] = {
3781 encoded_dollar_at
, NULL
3782 }; /* argv list with one element: "$@" */
3785 vals
= (char**)encoded_dollar_at_argv
;
3786 if (pi
->next
->res_word
== RES_IN
) {
3787 /* if no variable values after "in" we skip "for" */
3788 if (!pi
->next
->cmds
[0].argv
) {
3789 G
.last_exitcode
= rcode
= EXIT_SUCCESS
;
3790 debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
3793 vals
= pi
->next
->cmds
[0].argv
;
3794 } /* else: "for var; do..." -> assume "$@" list */
3795 /* create list of variable values */
3796 debug_print_strings("for_list made from", vals
);
3797 for_list
= expand_strvec_to_strvec(vals
);
3798 for_lcur
= for_list
;
3799 debug_print_strings("for_list", for_list
);
3800 for_varname
= pi
->cmds
[0].argv
[0];
3801 pi
->cmds
[0].argv
[0] = NULL
;
3803 free(pi
->cmds
[0].argv
[0]);
3805 /* "for" loop is over, clean up */
3809 pi
->cmds
[0].argv
[0] = for_varname
;
3812 /* Insert next value from for_lcur */
3813 /* note: *for_lcur already has quotes removed, $var expanded, etc */
3814 pi
->cmds
[0].argv
[0] = xasprintf("%s=%s", for_varname
, *for_lcur
++);
3815 pi
->cmds
[0].assignment_cnt
= 1;
3817 if (rword
== RES_IN
) {
3818 continue; /* "for v IN list;..." - "in" has no cmds anyway */
3820 if (rword
== RES_DONE
) {
3821 continue; /* "done" has no cmds too */
3824 #if ENABLE_HUSH_CASE
3825 if (rword
== RES_CASE
) {
3826 case_word
= expand_strvec_to_string(pi
->cmds
->argv
);
3829 if (rword
== RES_MATCH
) {
3832 if (!case_word
) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
3834 /* all prev words didn't match, does this one match? */
3835 argv
= pi
->cmds
->argv
;
3837 char *pattern
= expand_string_to_string(*argv
);
3838 /* TODO: which FNM_xxx flags to use? */
3839 cond_code
= (fnmatch(pattern
, case_word
, /*flags:*/ 0) != 0);
3841 if (cond_code
== 0) { /* match! we will execute this branch */
3842 free(case_word
); /* make future "word)" stop */
3850 if (rword
== RES_CASEI
) { /* inside of a case branch */
3852 continue; /* not matched yet, skip this pipe */
3855 /* Just pressing <enter> in shell should check for jobs.
3856 * OTOH, in non-interactive shell this is useless
3857 * and only leads to extra job checks */
3858 if (pi
->num_cmds
== 0) {
3859 if (G_interactive_fd
)
3860 goto check_jobs_and_continue
;
3864 /* After analyzing all keywords and conditions, we decided
3865 * to execute this pipe. NB: have to do checkjobs(NULL)
3866 * after run_pipe to collect any background children,
3867 * even if list execution is to be stopped. */
3868 debug_printf_exec(": run_pipe with %d members\n", pi
->num_cmds
);
3871 #if ENABLE_HUSH_LOOPS
3872 G
.flag_break_continue
= 0;
3874 rcode
= r
= run_pipe(pi
); /* NB: rcode is a smallint */
3876 /* We only ran a builtin: rcode is already known
3877 * and we don't need to wait for anything. */
3878 G
.last_exitcode
= rcode
;
3879 debug_printf_exec(": builtin/func exitcode %d\n", rcode
);
3880 check_and_run_traps(0);
3881 #if ENABLE_HUSH_LOOPS
3882 /* Was it "break" or "continue"? */
3883 if (G
.flag_break_continue
) {
3884 smallint fbc
= G
.flag_break_continue
;
3885 /* We might fall into outer *loop*,
3886 * don't want to break it too */
3888 G
.depth_break_continue
--;
3889 if (G
.depth_break_continue
== 0)
3890 G
.flag_break_continue
= 0;
3891 /* else: e.g. "continue 2" should *break* once, *then* continue */
3892 } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
3893 if (G
.depth_break_continue
!= 0 || fbc
== BC_BREAK
)
3894 goto check_jobs_and_break
;
3895 /* "continue": simulate end of loop */
3900 } else if (pi
->followup
== PIPE_BG
) {
3901 /* What does bash do with attempts to background builtins? */
3902 /* even bash 3.2 doesn't do that well with nested bg:
3903 * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
3904 * I'm NOT treating inner &'s as jobs */
3905 check_and_run_traps(0);
3907 if (G
.run_list_level
== 1)
3910 G
.last_exitcode
= rcode
= EXIT_SUCCESS
;
3911 debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
3914 if (G
.run_list_level
== 1 && G_interactive_fd
) {
3915 /* Waits for completion, then fg's main shell */
3916 rcode
= checkjobs_and_fg_shell(pi
);
3917 debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode
);
3918 check_and_run_traps(0);
3921 { /* This one just waits for completion */
3922 rcode
= checkjobs(pi
);
3923 debug_printf_exec(": checkjobs exitcode %d\n", rcode
);
3924 check_and_run_traps(0);
3926 G
.last_exitcode
= rcode
;
3930 /* Analyze how result affects subsequent commands */
3932 if (rword
== RES_IF
|| rword
== RES_ELIF
)
3935 #if ENABLE_HUSH_LOOPS
3936 /* Beware of "while false; true; do ..."! */
3937 if (pi
->next
&& pi
->next
->res_word
== RES_DO
) {
3938 if (rword
== RES_WHILE
) {
3940 /* "while false; do...done" - exitcode 0 */
3941 G
.last_exitcode
= rcode
= EXIT_SUCCESS
;
3942 debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
3943 goto check_jobs_and_break
;
3946 if (rword
== RES_UNTIL
) {
3948 debug_printf_exec(": until expr is true: breaking\n");
3949 check_jobs_and_break
:
3957 check_jobs_and_continue
:
3962 //// if (G.ctrl_z_flag) {
3963 //// /* ctrl-Z forked somewhere in the past, we are the child,
3964 //// * and now we completed running the list. Exit. */
3970 //// if (!G.run_list_level && G_interactive_fd) {
3971 //// signal(SIGTSTP, SIG_IGN);
3972 //// signal(SIGINT, SIG_IGN);
3975 #if ENABLE_HUSH_LOOPS
3980 #if ENABLE_HUSH_CASE
3984 debug_printf_exec("run_list lvl %d return %d\n", G
.run_list_level
+ 1, rcode
);
3988 /* Select which version we will use */
3989 static int run_and_free_list(struct pipe
*pi
)
3992 debug_printf_exec("run_and_free_list entered\n");
3994 debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi
->num_cmds
);
3995 rcode
= run_list(pi
);
3997 /* free_pipe_list has the side effect of clearing memory.
3998 * In the long run that function can be merged with run_list,
3999 * but doing that now would hobble the debugging effort. */
4001 debug_printf_exec("run_and_free_list return %d\n", rcode
);
4006 static struct pipe
*new_pipe(void)
4009 pi
= xzalloc(sizeof(struct pipe
));
4010 /*pi->followup = 0; - deliberately invalid value */
4011 /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
4015 /* Command (member of a pipe) is complete. The only possible error here
4016 * is out of memory, in which case xmalloc exits. */
4017 static int done_command(struct parse_context
*ctx
)
4019 /* The command is really already in the pipe structure, so
4020 * advance the pipe counter and make a new, null command. */
4021 struct pipe
*pi
= ctx
->pipe
;
4022 struct command
*command
= ctx
->command
;
4025 if (command
->group
== NULL
4026 && command
->argv
== NULL
4027 && command
->redirects
== NULL
4029 debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi
->num_cmds
);
4030 memset(command
, 0, sizeof(*command
)); /* paranoia */
4031 return pi
->num_cmds
;
4034 debug_printf_parse("done_command: ++num_cmds=%d\n", pi
->num_cmds
);
4035 //debug_print_tree(ctx->list_head, 20);
4037 debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi
->num_cmds
);
4040 /* Only real trickiness here is that the uncommitted
4041 * command structure is not counted in pi->num_cmds. */
4042 pi
->cmds
= xrealloc(pi
->cmds
, sizeof(*pi
->cmds
) * (pi
->num_cmds
+1));
4043 command
= &pi
->cmds
[pi
->num_cmds
];
4044 memset(command
, 0, sizeof(*command
));
4046 ctx
->command
= command
;
4047 /* but ctx->pipe and ctx->list_head remain unchanged */
4049 return pi
->num_cmds
; /* used only for 0/nonzero check */
4052 static void done_pipe(struct parse_context
*ctx
, pipe_style type
)
4056 debug_printf_parse("done_pipe entered, followup %d\n", type
);
4057 /* Close previous command */
4058 not_null
= done_command(ctx
);
4059 ctx
->pipe
->followup
= type
;
4061 ctx
->pipe
->pi_inverted
= ctx
->ctx_inverted
;
4062 ctx
->ctx_inverted
= 0;
4063 ctx
->pipe
->res_word
= ctx
->ctx_res_w
;
4066 /* Without this check, even just <enter> on command line generates
4067 * tree of three NOPs (!). Which is harmless but annoying.
4068 * IOW: it is safe to do it unconditionally.
4069 * RES_NONE case is for "for a in; do ..." (empty IN set)
4070 * and other cases to work. */
4073 || ctx
->ctx_res_w
== RES_FI
4075 #if ENABLE_HUSH_LOOPS
4076 || ctx
->ctx_res_w
== RES_DONE
4077 || ctx
->ctx_res_w
== RES_FOR
4078 || ctx
->ctx_res_w
== RES_IN
4080 #if ENABLE_HUSH_CASE
4081 || ctx
->ctx_res_w
== RES_ESAC
4085 debug_printf_parse("done_pipe: adding new pipe: "
4086 "not_null:%d ctx->ctx_res_w:%d\n",
4087 not_null
, ctx
->ctx_res_w
);
4089 ctx
->pipe
->next
= new_p
;
4091 /* RES_THEN, RES_DO etc are "sticky" -
4092 * they remain set for commands inside if/while.
4093 * This is used to control execution.
4094 * RES_FOR and RES_IN are NOT sticky (needed to support
4095 * cases where variable or value happens to match a keyword):
4097 #if ENABLE_HUSH_LOOPS
4098 if (ctx
->ctx_res_w
== RES_FOR
4099 || ctx
->ctx_res_w
== RES_IN
)
4100 ctx
->ctx_res_w
= RES_NONE
;
4102 #if ENABLE_HUSH_CASE
4103 if (ctx
->ctx_res_w
== RES_MATCH
)
4104 ctx
->ctx_res_w
= RES_CASEI
;
4106 ctx
->command
= NULL
; /* trick done_command below */
4107 /* Create the memory for command, roughly:
4108 * ctx->pipe->cmds = new struct command;
4109 * ctx->command = &ctx->pipe->cmds[0];
4112 //debug_print_tree(ctx->list_head, 10);
4114 debug_printf_parse("done_pipe return\n");
4117 static void initialize_context(struct parse_context
*ctx
)
4119 memset(ctx
, 0, sizeof(*ctx
));
4120 ctx
->pipe
= ctx
->list_head
= new_pipe();
4121 /* Create the memory for command, roughly:
4122 * ctx->pipe->cmds = new struct command;
4123 * ctx->command = &ctx->pipe->cmds[0];
4128 /* If a reserved word is found and processed, parse context is modified
4129 * and 1 is returned.
4132 struct reserved_combo
{
4135 unsigned char assignment_flag
;
4139 FLAG_END
= (1 << RES_NONE
),
4141 FLAG_IF
= (1 << RES_IF
),
4142 FLAG_THEN
= (1 << RES_THEN
),
4143 FLAG_ELIF
= (1 << RES_ELIF
),
4144 FLAG_ELSE
= (1 << RES_ELSE
),
4145 FLAG_FI
= (1 << RES_FI
),
4147 #if ENABLE_HUSH_LOOPS
4148 FLAG_FOR
= (1 << RES_FOR
),
4149 FLAG_WHILE
= (1 << RES_WHILE
),
4150 FLAG_UNTIL
= (1 << RES_UNTIL
),
4151 FLAG_DO
= (1 << RES_DO
),
4152 FLAG_DONE
= (1 << RES_DONE
),
4153 FLAG_IN
= (1 << RES_IN
),
4155 #if ENABLE_HUSH_CASE
4156 FLAG_MATCH
= (1 << RES_MATCH
),
4157 FLAG_ESAC
= (1 << RES_ESAC
),
4159 FLAG_START
= (1 << RES_XXXX
),
4162 static const struct reserved_combo
* match_reserved_word(o_string
*word
)
4164 /* Mostly a list of accepted follow-up reserved words.
4165 * FLAG_END means we are done with the sequence, and are ready
4166 * to turn the compound list into a command.
4167 * FLAG_START means the word must start a new compound list.
4169 static const struct reserved_combo reserved_list
[] = {
4171 { "!", RES_NONE
, NOT_ASSIGNMENT
, 0 },
4172 { "if", RES_IF
, WORD_IS_KEYWORD
, FLAG_THEN
| FLAG_START
},
4173 { "then", RES_THEN
, WORD_IS_KEYWORD
, FLAG_ELIF
| FLAG_ELSE
| FLAG_FI
},
4174 { "elif", RES_ELIF
, WORD_IS_KEYWORD
, FLAG_THEN
},
4175 { "else", RES_ELSE
, WORD_IS_KEYWORD
, FLAG_FI
},
4176 { "fi", RES_FI
, NOT_ASSIGNMENT
, FLAG_END
},
4178 #if ENABLE_HUSH_LOOPS
4179 { "for", RES_FOR
, NOT_ASSIGNMENT
, FLAG_IN
| FLAG_DO
| FLAG_START
},
4180 { "while", RES_WHILE
, WORD_IS_KEYWORD
, FLAG_DO
| FLAG_START
},
4181 { "until", RES_UNTIL
, WORD_IS_KEYWORD
, FLAG_DO
| FLAG_START
},
4182 { "in", RES_IN
, NOT_ASSIGNMENT
, FLAG_DO
},
4183 { "do", RES_DO
, WORD_IS_KEYWORD
, FLAG_DONE
},
4184 { "done", RES_DONE
, NOT_ASSIGNMENT
, FLAG_END
},
4186 #if ENABLE_HUSH_CASE
4187 { "case", RES_CASE
, NOT_ASSIGNMENT
, FLAG_MATCH
| FLAG_START
},
4188 { "esac", RES_ESAC
, NOT_ASSIGNMENT
, FLAG_END
},
4191 const struct reserved_combo
*r
;
4193 for (r
= reserved_list
; r
< reserved_list
+ ARRAY_SIZE(reserved_list
); r
++) {
4194 if (strcmp(word
->data
, r
->literal
) == 0)
4199 static int reserved_word(o_string
*word
, struct parse_context
*ctx
)
4201 #if ENABLE_HUSH_CASE
4202 static const struct reserved_combo reserved_match
= {
4203 "", RES_MATCH
, NOT_ASSIGNMENT
, FLAG_MATCH
| FLAG_ESAC
4206 const struct reserved_combo
*r
;
4208 r
= match_reserved_word(word
);
4212 debug_printf("found reserved word %s, res %d\n", r
->literal
, r
->res
);
4213 #if ENABLE_HUSH_CASE
4214 if (r
->res
== RES_IN
&& ctx
->ctx_res_w
== RES_CASE
)
4215 /* "case word IN ..." - IN part starts first match part */
4216 r
= &reserved_match
;
4219 if (r
->flag
== 0) { /* '!' */
4220 if (ctx
->ctx_inverted
) { /* bash doesn't accept '! ! true' */
4221 syntax_error("! ! command");
4222 IF_HAS_KEYWORDS(ctx
->ctx_res_w
= RES_SNTX
;)
4224 ctx
->ctx_inverted
= 1;
4227 if (r
->flag
& FLAG_START
) {
4228 struct parse_context
*old
;
4229 old
= xmalloc(sizeof(*old
));
4230 debug_printf_parse("push stack %p\n", old
);
4231 *old
= *ctx
; /* physical copy */
4232 initialize_context(ctx
);
4234 } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx
->old_flag
& (1 << r
->res
))) {
4235 syntax_error_at(word
->data
);
4236 ctx
->ctx_res_w
= RES_SNTX
;
4239 ctx
->ctx_res_w
= r
->res
;
4240 ctx
->old_flag
= r
->flag
;
4241 if (ctx
->old_flag
& FLAG_END
) {
4242 struct parse_context
*old
;
4243 done_pipe(ctx
, PIPE_SEQ
);
4244 debug_printf_parse("pop stack %p\n", ctx
->stack
);
4246 old
->command
->group
= ctx
->list_head
;
4247 old
->command
->grp_type
= GRP_NORMAL
;
4249 o_addstr(&old
->as_string
, ctx
->as_string
.data
);
4250 o_free_unsafe(&ctx
->as_string
);
4251 old
->command
->group_as_string
= xstrdup(old
->as_string
.data
);
4252 debug_printf_parse("pop, remembering as:'%s'\n",
4253 old
->command
->group_as_string
);
4255 *ctx
= *old
; /* physical copy */
4258 word
->o_assignment
= r
->assignment_flag
;
4263 /* Word is complete, look at it and update parsing context.
4264 * Normal return is 0. Syntax errors return 1.
4265 * Note: on return, word is reset, but not o_free'd!
4267 static int done_word(o_string
*word
, struct parse_context
*ctx
)
4269 struct command
*command
= ctx
->command
;
4271 debug_printf_parse("done_word entered: '%s' %p\n", word
->data
, command
);
4272 if (word
->length
== 0 && word
->o_quoted
== 0) {
4273 debug_printf_parse("done_word return 0: true null, ignored\n");
4277 if (ctx
->pending_redirect
) {
4278 /* We do not glob in e.g. >*.tmp case. bash seems to glob here
4279 * only if run as "bash", not "sh" */
4280 /* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
4282 * ...the word that follows the redirection operator
4283 * shall be subjected to tilde expansion, parameter expansion,
4284 * command substitution, arithmetic expansion, and quote
4285 * removal. Pathname expansion shall not be performed
4286 * on the word by a non-interactive shell; an interactive
4287 * shell may perform it, but shall do so only when
4288 * the expansion would result in one word."
4290 ctx
->pending_redirect
->rd_filename
= xstrdup(word
->data
);
4291 /* Cater for >\file case:
4292 * >\a creates file a; >\\a, >"\a", >"\\a" create file \a
4293 * Same with heredocs:
4294 * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H
4296 unbackslash(ctx
->pending_redirect
->rd_filename
);
4297 /* Is it <<"HEREDOC"? */
4298 if (ctx
->pending_redirect
->rd_type
== REDIRECT_HEREDOC
4301 ctx
->pending_redirect
->rd_dup
|= HEREDOC_QUOTED
;
4303 debug_printf_parse("word stored in rd_filename: '%s'\n", word
->data
);
4304 ctx
->pending_redirect
= NULL
;
4306 /* If this word wasn't an assignment, next ones definitely
4307 * can't be assignments. Even if they look like ones. */
4308 if (word
->o_assignment
!= DEFINITELY_ASSIGNMENT
4309 && word
->o_assignment
!= WORD_IS_KEYWORD
4311 word
->o_assignment
= NOT_ASSIGNMENT
;
4313 if (word
->o_assignment
== DEFINITELY_ASSIGNMENT
)
4314 command
->assignment_cnt
++;
4315 word
->o_assignment
= MAYBE_ASSIGNMENT
;
4318 if (command
->group
) {
4319 /* "{ echo foo; } echo bar" - bad */
4320 /* NB: bash allows e.g.:
4321 * if true; then { echo foo; } fi
4322 * while if false; then false; fi do break; done
4324 * while if false; then false; fi; do; break; done
4326 syntax_error_at(word
->data
);
4327 debug_printf_parse("done_word return 1: syntax error, "
4328 "groups and arglists don't mix\n");
4332 # if ENABLE_HUSH_CASE
4333 if (ctx
->ctx_dsemicolon
4334 && strcmp(word
->data
, "esac") != 0 /* not "... pattern) cmd;; esac" */
4336 /* already done when ctx_dsemicolon was set to 1: */
4337 /* ctx->ctx_res_w = RES_MATCH; */
4338 ctx
->ctx_dsemicolon
= 0;
4341 if (!command
->argv
/* if it's the first word... */
4342 # if ENABLE_HUSH_LOOPS
4343 && ctx
->ctx_res_w
!= RES_FOR
/* ...not after FOR or IN */
4344 && ctx
->ctx_res_w
!= RES_IN
4347 debug_printf_parse(": checking '%s' for reserved-ness\n", word
->data
);
4348 if (reserved_word(word
, ctx
)) {
4349 o_reset_to_empty_unquoted(word
);
4350 debug_printf_parse("done_word return %d\n",
4351 (ctx
->ctx_res_w
== RES_SNTX
));
4352 return (ctx
->ctx_res_w
== RES_SNTX
);
4356 if (word
->o_quoted
/* word had "xx" or 'xx' at least as part of it. */
4357 /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
4358 && (word
->data
[0] == '\0' || word
->data
[0] == SPECIAL_VAR_SYMBOL
)
4359 /* (otherwise it's known to be not empty and is already safe) */
4361 /* exclude "$@" - it can expand to no word despite "" */
4362 char *p
= word
->data
;
4363 while (p
[0] == SPECIAL_VAR_SYMBOL
4364 && (p
[1] & 0x7f) == '@'
4365 && p
[2] == SPECIAL_VAR_SYMBOL
4369 if (p
== word
->data
|| p
[0] != '\0') {
4370 /* saw no "$@", or not only "$@" but some
4371 * real text is there too */
4372 /* insert "empty variable" reference, this makes
4373 * e.g. "", $empty"" etc to not disappear */
4374 o_addchr(word
, SPECIAL_VAR_SYMBOL
);
4375 o_addchr(word
, SPECIAL_VAR_SYMBOL
);
4378 command
->argv
= add_string_to_strings(command
->argv
, xstrdup(word
->data
));
4379 //SEGV, but good idea.
4380 // command->argv = add_string_to_strings(command->argv, word->data);
4381 // word->data = NULL;
4382 // word->length = 0;
4383 debug_print_strings("word appended to argv", command
->argv
);
4386 #if ENABLE_HUSH_LOOPS
4387 if (ctx
->ctx_res_w
== RES_FOR
) {
4389 || !is_well_formed_var_name(command
->argv
[0], '\0')
4391 /* bash says just "not a valid identifier" */
4392 syntax_error("not a valid identifier in for");
4395 /* Force FOR to have just one word (variable name) */
4396 /* NB: basically, this makes hush see "for v in ..."
4397 * syntax as if it is "for v; in ...". FOR and IN become
4398 * two pipe structs in parse tree. */
4399 done_pipe(ctx
, PIPE_SEQ
);
4402 #if ENABLE_HUSH_CASE
4403 /* Force CASE to have just one word */
4404 if (ctx
->ctx_res_w
== RES_CASE
) {
4405 done_pipe(ctx
, PIPE_SEQ
);
4409 o_reset_to_empty_unquoted(word
);
4411 debug_printf_parse("done_word return 0\n");
4416 /* Peek ahead in the input to find out if we have a "&n" construct,
4417 * as in "2>&1", that represents duplicating a file descriptor.
4419 * REDIRFD_CLOSE if >&- "close fd" construct is seen,
4420 * REDIRFD_SYNTAX_ERR if syntax error,
4421 * REDIRFD_TO_FILE if no & was seen,
4422 * or the number found.
4425 #define parse_redir_right_fd(as_string, input) \
4426 parse_redir_right_fd(input)
4428 static int parse_redir_right_fd(o_string
*as_string
, struct in_str
*input
)
4434 return REDIRFD_TO_FILE
;
4436 ch
= i_getch(input
); /* get the & */
4437 nommu_addchr(as_string
, ch
);
4440 ch
= i_getch(input
);
4441 nommu_addchr(as_string
, ch
);
4442 return REDIRFD_CLOSE
;
4446 while (ch
!= EOF
&& isdigit(ch
)) {
4447 d
= d
*10 + (ch
-'0');
4449 ch
= i_getch(input
);
4450 nommu_addchr(as_string
, ch
);
4455 //TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
4457 bb_error_msg("ambiguous redirect");
4458 return REDIRFD_SYNTAX_ERR
;
4461 /* Return code is 0 normal, 1 if a syntax error is detected
4463 static int parse_redirect(struct parse_context
*ctx
,
4466 struct in_str
*input
)
4468 struct command
*command
= ctx
->command
;
4469 struct redir_struct
*redir
;
4470 struct redir_struct
**redirp
;
4473 dup_num
= REDIRFD_TO_FILE
;
4474 if (style
!= REDIRECT_HEREDOC
) {
4475 /* Check for a '>&1' type redirect */
4476 dup_num
= parse_redir_right_fd(&ctx
->as_string
, input
);
4477 if (dup_num
== REDIRFD_SYNTAX_ERR
)
4480 int ch
= i_peek(input
);
4481 dup_num
= (ch
== '-'); /* HEREDOC_SKIPTABS bit is 1 */
4482 if (dup_num
) { /* <<-... */
4483 ch
= i_getch(input
);
4484 nommu_addchr(&ctx
->as_string
, ch
);
4489 if (style
== REDIRECT_OVERWRITE
&& dup_num
== REDIRFD_TO_FILE
) {
4490 int ch
= i_peek(input
);
4492 /* >|FILE redirect ("clobbering" >).
4493 * Since we do not support "set -o noclobber" yet,
4494 * >| and > are the same for now. Just eat |.
4496 ch
= i_getch(input
);
4497 nommu_addchr(&ctx
->as_string
, ch
);
4501 /* Create a new redir_struct and append it to the linked list */
4502 redirp
= &command
->redirects
;
4503 while ((redir
= *redirp
) != NULL
) {
4504 redirp
= &(redir
->next
);
4506 *redirp
= redir
= xzalloc(sizeof(*redir
));
4507 /* redir->next = NULL; */
4508 /* redir->rd_filename = NULL; */
4509 redir
->rd_type
= style
;
4510 redir
->rd_fd
= (fd
== -1) ? redir_table
[style
].default_fd
: fd
;
4512 debug_printf_parse("redirect type %d %s\n", redir
->rd_fd
,
4513 redir_table
[style
].descrip
);
4515 redir
->rd_dup
= dup_num
;
4516 if (style
!= REDIRECT_HEREDOC
&& dup_num
!= REDIRFD_TO_FILE
) {
4517 /* Erik had a check here that the file descriptor in question
4518 * is legit; I postpone that to "run time"
4519 * A "-" representation of "close me" shows up as a -3 here */
4520 debug_printf_parse("duplicating redirect '%d>&%d'\n",
4521 redir
->rd_fd
, redir
->rd_dup
);
4523 /* Set ctx->pending_redirect, so we know what to do at the
4524 * end of the next parsed word. */
4525 ctx
->pending_redirect
= redir
;
4530 /* If a redirect is immediately preceded by a number, that number is
4531 * supposed to tell which file descriptor to redirect. This routine
4532 * looks for such preceding numbers. In an ideal world this routine
4533 * needs to handle all the following classes of redirects...
4534 * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
4535 * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
4536 * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
4537 * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
4539 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
4541 * ... If n is quoted, the number shall not be recognized as part of
4542 * the redirection expression. For example:
4544 * writes the character 2 into file a"
4545 * We are getting it right by setting ->o_quoted on any \<char>
4547 * A -1 return means no valid number was found,
4548 * the caller should use the appropriate default for this redirection.
4550 static int redirect_opt_num(o_string
*o
)
4554 if (o
->data
== NULL
)
4556 num
= bb_strtou(o
->data
, NULL
, 10);
4557 if (errno
|| num
< 0)
4559 o_reset_to_empty_unquoted(o
);
4564 #define fetch_till_str(as_string, input, word, skip_tabs) \
4565 fetch_till_str(input, word, skip_tabs)
4567 static char *fetch_till_str(o_string
*as_string
,
4568 struct in_str
*input
,
4572 o_string heredoc
= NULL_O_STRING
;
4578 ch
= i_getch(input
);
4579 nommu_addchr(as_string
, ch
);
4581 if (strcmp(heredoc
.data
+ past_EOL
, word
) == 0) {
4582 heredoc
.data
[past_EOL
] = '\0';
4583 debug_printf_parse("parsed heredoc '%s'\n", heredoc
.data
);
4584 return heredoc
.data
;
4587 o_addchr(&heredoc
, ch
);
4588 past_EOL
= heredoc
.length
;
4591 ch
= i_getch(input
);
4592 nommu_addchr(as_string
, ch
);
4593 } while (skip_tabs
&& ch
== '\t');
4594 } while (ch
== '\n');
4597 o_free_unsafe(&heredoc
);
4600 o_addchr(&heredoc
, ch
);
4601 nommu_addchr(as_string
, ch
);
4605 /* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs
4606 * and load them all. There should be exactly heredoc_cnt of them.
4608 static int fetch_heredocs(int heredoc_cnt
, struct parse_context
*ctx
, struct in_str
*input
)
4610 struct pipe
*pi
= ctx
->list_head
;
4612 while (pi
&& heredoc_cnt
) {
4614 struct command
*cmd
= pi
->cmds
;
4616 debug_printf_parse("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
4618 cmd
->argv
? cmd
->argv
[0] : "NONE");
4619 for (i
= 0; i
< pi
->num_cmds
; i
++) {
4620 struct redir_struct
*redir
= cmd
->redirects
;
4622 debug_printf_parse("fetch_heredocs: %d cmd argv0:'%s'\n",
4623 i
, cmd
->argv
? cmd
->argv
[0] : "NONE");
4625 if (redir
->rd_type
== REDIRECT_HEREDOC
) {
4628 redir
->rd_type
= REDIRECT_HEREDOC2
;
4629 /* redir->dup is (ab)used to indicate <<- */
4630 p
= fetch_till_str(&ctx
->as_string
, input
,
4631 redir
->rd_filename
, redir
->rd_dup
& HEREDOC_SKIPTABS
);
4633 syntax_error("unexpected EOF in here document");
4636 free(redir
->rd_filename
);
4637 redir
->rd_filename
= p
;
4640 redir
= redir
->next
;
4647 /* Should be 0. If it isn't, it's a parse error */
4649 bb_error_msg_and_die("heredoc BUG 2");
4655 #if ENABLE_HUSH_TICK
4656 static FILE *generate_stream_from_string(const char *s
)
4659 int pid
, channel
[2];
4662 pid
= BB_MMU
? fork() : vfork();
4664 bb_perror_msg_and_die(BB_MMU
? "fork" : "vfork");
4666 if (pid
== 0) { /* child */
4667 disable_restore_tty_pgrp_on_exit();
4668 /* Process substitution is not considered to be usual
4669 * 'command execution'.
4670 * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
4677 close(channel
[0]); /* NB: close _first_, then move fd! */
4678 xmove_fd(channel
[1], 1);
4679 /* Prevent it from trying to handle ctrl-z etc */
4680 USE_HUSH_JOB(G
.run_list_level
= 1;)
4682 reset_traps_to_defaults();
4683 parse_and_run_string(s
);
4684 _exit(G
.last_exitcode
);
4686 /* We re-execute after vfork on NOMMU. This makes this script safe:
4687 * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
4688 * huge=`cat BIG` # was blocking here forever
4698 enable_restore_tty_pgrp_on_exit();
4699 clean_up_after_re_execute();
4701 pf
= fdopen(channel
[0], "r");
4705 /* Return code is exit status of the process that is run. */
4706 static int process_command_subs(o_string
*dest
, const char *s
)
4709 struct in_str pipe_str
;
4712 pf
= generate_stream_from_string(s
);
4715 close_on_exec_on(fileno(pf
));
4717 /* Now send results of command back into original context */
4718 setup_file_in_str(&pipe_str
, pf
);
4720 while ((ch
= i_getch(&pipe_str
)) != EOF
) {
4726 o_addchr(dest
, '\n');
4729 o_addQchr(dest
, ch
);
4732 debug_printf("done reading from pipe, pclose()ing\n");
4733 /* Note: we got EOF, and we just close the read end of the pipe.
4734 * We do not wait for the `cmd` child to terminate. bash and ash do.
4736 * echo `echo Hi; exec 1>&-; sleep 2` - bash waits 2 sec
4737 * `false`; echo $? - bash outputs "1"
4740 debug_printf("closed FILE from child. return 0\n");
4745 static int parse_group(o_string
*dest
, struct parse_context
*ctx
,
4746 struct in_str
*input
, int ch
)
4748 /* dest contains characters seen prior to ( or {.
4749 * Typically it's empty, but for function defs,
4750 * it contains function name (without '()'). */
4751 struct pipe
*pipe_list
;
4753 struct command
*command
= ctx
->command
;
4755 debug_printf_parse("parse_group entered\n");
4756 #if ENABLE_HUSH_FUNCTIONS
4757 if (ch
== '(' && !dest
->o_quoted
) {
4759 done_word(dest
, ctx
);
4761 goto skip
; /* (... */
4762 if (command
->argv
[1]) { /* word word ... (... */
4763 syntax_error_unexpected_ch('(');
4766 /* it is "word(..." or "word (..." */
4768 ch
= i_getch(input
);
4769 while (ch
== ' ' || ch
== '\t');
4771 syntax_error_unexpected_ch(ch
);
4774 nommu_addchr(&ctx
->as_string
, ch
);
4776 ch
= i_getch(input
);
4777 while (ch
== ' ' || ch
== '\t' || ch
== '\n');
4779 syntax_error_unexpected_ch(ch
);
4782 nommu_addchr(&ctx
->as_string
, ch
);
4783 command
->grp_type
= GRP_FUNCTION
;
4787 if (command
->argv
/* word [word]{... */
4788 || dest
->length
/* word{... */
4789 || dest
->o_quoted
/* ""{... */
4792 debug_printf_parse("parse_group return 1: "
4793 "syntax error, groups and arglists don't mix\n");
4797 #if ENABLE_HUSH_FUNCTIONS
4803 command
->grp_type
= GRP_SUBSHELL
;
4808 char *as_string
= NULL
;
4810 pipe_list
= parse_stream(&as_string
, input
, endch
);
4813 o_addstr(&ctx
->as_string
, as_string
);
4815 /* empty ()/{} or parse error? */
4816 if (!pipe_list
|| pipe_list
== ERR_PTR
) {
4821 debug_printf_parse("parse_group return 1: "
4822 "parse_stream returned %p\n", pipe_list
);
4825 command
->group
= pipe_list
;
4827 as_string
[strlen(as_string
) - 1] = '\0'; /* plink ')' or '}' */
4828 command
->group_as_string
= as_string
;
4829 debug_printf_parse("end of group, remembering as:'%s'\n",
4830 command
->group_as_string
);
4833 debug_printf_parse("parse_group return 0\n");
4835 /* command remains "open", available for possible redirects */
4838 #if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT
4839 /* Subroutines for copying $(...) and `...` things */
4840 static void add_till_backquote(o_string
*dest
, struct in_str
*input
);
4842 static void add_till_single_quote(o_string
*dest
, struct in_str
*input
)
4845 int ch
= i_getch(input
);
4847 syntax_error_unterm_ch('\'');
4848 /*xfunc_die(); - redundant */
4855 /* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
4856 static void add_till_double_quote(o_string
*dest
, struct in_str
*input
)
4859 int ch
= i_getch(input
);
4861 syntax_error_unterm_ch('"');
4862 /*xfunc_die(); - redundant */
4866 if (ch
== '\\') { /* \x. Copy both chars. */
4868 ch
= i_getch(input
);
4872 add_till_backquote(dest
, input
);
4876 //if (ch == '$') ...
4879 /* Process `cmd` - copy contents until "`" is seen. Complicated by
4881 * "Within the backquoted style of command substitution, backslash
4882 * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
4883 * The search for the matching backquote shall be satisfied by the first
4884 * backquote found without a preceding backslash; during this search,
4885 * if a non-escaped backquote is encountered within a shell comment,
4886 * a here-document, an embedded command substitution of the $(command)
4887 * form, or a quoted string, undefined results occur. A single-quoted
4888 * or double-quoted string that begins, but does not end, within the
4889 * "`...`" sequence produces undefined results."
4891 * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
4893 static void add_till_backquote(o_string
*dest
, struct in_str
*input
)
4896 int ch
= i_getch(input
);
4898 syntax_error_unterm_ch('`');
4899 /*xfunc_die(); - redundant */
4904 /* \x. Copy both chars unless it is \` */
4905 int ch2
= i_getch(input
);
4907 syntax_error_unterm_ch('`');
4908 /*xfunc_die(); - redundant */
4910 if (ch2
!= '`' && ch2
!= '$' && ch2
!= '\\')
4917 /* Process $(cmd) - copy contents until ")" is seen. Complicated by
4918 * quoting and nested ()s.
4919 * "With the $(command) style of command substitution, all characters
4920 * following the open parenthesis to the matching closing parenthesis
4921 * constitute the command. Any valid shell script can be used for command,
4922 * except a script consisting solely of redirections which produces
4923 * unspecified results."
4925 * echo $(echo '(TEST)' BEST) (TEST) BEST
4926 * echo $(echo 'TEST)' BEST) TEST) BEST
4927 * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
4929 static void add_till_closing_paren(o_string
*dest
, struct in_str
*input
, bool dbl
)
4933 int ch
= i_getch(input
);
4935 syntax_error_unterm_ch(')');
4936 /*xfunc_die(); - redundant */
4944 if (i_peek(input
) == ')') {
4952 add_till_single_quote(dest
, input
);
4957 add_till_double_quote(dest
, input
);
4962 /* \x. Copy verbatim. Important for \(, \) */
4963 ch
= i_getch(input
);
4965 syntax_error_unterm_ch(')');
4966 /*xfunc_die(); - redundant */
4973 #endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT */
4975 /* Return code: 0 for OK, 1 for syntax error */
4977 #define handle_dollar(as_string, dest, input) \
4978 handle_dollar(dest, input)
4980 static int handle_dollar(o_string
*as_string
,
4982 struct in_str
*input
)
4985 int ch
= i_peek(input
); /* first character after the $ */
4986 unsigned char quote_mask
= dest
->o_escape
? 0x80 : 0;
4988 debug_printf_parse("handle_dollar entered: ch='%c'\n", ch
);
4990 ch
= i_getch(input
);
4991 nommu_addchr(as_string
, ch
);
4993 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
4995 debug_printf_parse(": '%c'\n", ch
);
4996 o_addchr(dest
, ch
| quote_mask
);
4999 if (!isalnum(ch
) && ch
!= '_')
5001 ch
= i_getch(input
);
5002 nommu_addchr(as_string
, ch
);
5004 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5005 } else if (isdigit(ch
)) {
5007 ch
= i_getch(input
);
5008 nommu_addchr(as_string
, ch
);
5009 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5010 debug_printf_parse(": '%c'\n", ch
);
5011 o_addchr(dest
, ch
| quote_mask
);
5012 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5013 } else switch (ch
) {
5015 case '!': /* last bg pid */
5016 case '?': /* last exit code */
5017 case '#': /* number of args */
5018 case '*': /* args */
5019 case '@': /* args */
5020 goto make_one_char_var
;
5022 bool first_char
, all_digits
;
5024 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5025 ch
= i_getch(input
);
5026 nommu_addchr(as_string
, ch
);
5027 /* XXX maybe someone will try to escape the '}' */
5032 ch
= i_getch(input
);
5033 nommu_addchr(as_string
, ch
);
5039 /* ${#var}: length of var contents */
5041 else if (isdigit(ch
)) {
5048 && ( (all_digits
&& !isdigit(ch
))
5049 || (!all_digits
&& !isalnum(ch
) && ch
!= '_')
5052 /* handle parameter expansions
5053 * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
5058 case ':': /* null modifier */
5059 if (expansion
== 0) {
5060 debug_printf_parse(": null modifier\n");
5065 case '#': /* remove prefix */
5066 case '%': /* remove suffix */
5067 if (expansion
== 0) {
5068 debug_printf_parse(": remove suffix/prefix\n");
5073 case '-': /* default value */
5074 case '=': /* assign default */
5075 case '+': /* alternative */
5076 case '?': /* error indicate */
5077 debug_printf_parse(": parameter expansion\n");
5082 syntax_error_unterm_str("${name}");
5083 debug_printf_parse("handle_dollar return 1: unterminated ${name}\n");
5088 debug_printf_parse(": '%c'\n", ch
);
5089 o_addchr(dest
, ch
| quote_mask
);
5093 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5096 #if (ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK)
5101 ch
= i_getch(input
);
5102 nommu_addchr(as_string
, ch
);
5103 # if ENABLE_SH_MATH_SUPPORT
5104 if (i_peek(input
) == '(') {
5105 ch
= i_getch(input
);
5106 nommu_addchr(as_string
, ch
);
5107 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5108 o_addchr(dest
, /*quote_mask |*/ '+');
5112 add_till_closing_paren(dest
, input
, true);
5115 o_addstr(as_string
, dest
->data
+ pos
);
5116 o_addchr(as_string
, ')');
5117 o_addchr(as_string
, ')');
5120 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5124 # if ENABLE_HUSH_TICK
5125 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5126 o_addchr(dest
, quote_mask
| '`');
5130 add_till_closing_paren(dest
, input
, false);
5133 o_addstr(as_string
, dest
->data
+ pos
);
5134 o_addchr(as_string
, '`');
5137 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5143 ch
= i_getch(input
);
5144 nommu_addchr(as_string
, ch
);
5146 if (isalnum(ch
)) { /* it's $_name or $_123 */
5152 /* $_ Shell or shell script name; or last cmd name */
5153 /* $- Option flags set by set builtin or shell options (-i etc) */
5155 o_addQchr(dest
, '$');
5157 debug_printf_parse("handle_dollar return 0\n");
5162 #define parse_stream_dquoted(as_string, dest, input, dquote_end) \
5163 parse_stream_dquoted(dest, input, dquote_end)
5165 static int parse_stream_dquoted(o_string
*as_string
,
5167 struct in_str
*input
,
5174 ch
= i_getch(input
);
5176 nommu_addchr(as_string
, ch
);
5177 if (ch
== dquote_end
) { /* may be only '"' or EOF */
5178 if (dest
->o_assignment
== NOT_ASSIGNMENT
)
5179 dest
->o_escape
^= 1;
5180 debug_printf_parse("parse_stream_dquoted return 0\n");
5183 /* note: can't move it above ch == dquote_end check! */
5185 syntax_error_unterm_ch('"');
5186 /*xfunc_die(); - redundant */
5190 next
= i_peek(input
);
5192 debug_printf_parse(": ch=%c (%d) escape=%d\n",
5193 ch
, ch
, dest
->o_escape
);
5196 syntax_error("\\<eof>");
5200 * "The backslash retains its special meaning [in "..."]
5201 * only when followed by one of the following characters:
5202 * $, `, ", \, or <newline>. A double quote may be quoted
5203 * within double quotes by preceding it with a backslash.
5205 if (strchr("$`\"\\", next
) != NULL
) {
5206 o_addqchr(dest
, i_getch(input
));
5208 o_addqchr(dest
, '\\');
5213 if (handle_dollar(as_string
, dest
, input
) != 0) {
5214 debug_printf_parse("parse_stream_dquoted return 1: "
5215 "handle_dollar returned non-0\n");
5220 #if ENABLE_HUSH_TICK
5222 //int pos = dest->length;
5223 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5224 o_addchr(dest
, 0x80 | '`');
5225 add_till_backquote(dest
, input
);
5226 o_addchr(dest
, SPECIAL_VAR_SYMBOL
);
5227 //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
5231 o_addQchr(dest
, ch
);
5233 && (dest
->o_assignment
== MAYBE_ASSIGNMENT
5234 || dest
->o_assignment
== WORD_IS_KEYWORD
)
5235 && is_well_formed_var_name(dest
->data
, '=')
5237 dest
->o_assignment
= DEFINITELY_ASSIGNMENT
;
5243 * Scan input until EOF or end_trigger char.
5244 * Return a list of pipes to execute, or NULL on EOF
5245 * or if end_trigger character is met.
5246 * On syntax error, exit is shell is not interactive,
5247 * reset parsing machinery and start parsing anew,
5248 * or return ERR_PTR.
5250 static struct pipe
*parse_stream(char **pstring
,
5251 struct in_str
*input
,
5254 struct parse_context ctx
;
5255 o_string dest
= NULL_O_STRING
;
5259 /* Double-quote state is handled in the state variable is_in_dquote.
5260 * A single-quote triggers a bypass of the main loop until its mate is
5261 * found. When recursing, quote state is passed in via dest->o_escape.
5263 debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
5264 end_trigger
? : 'X');
5267 G
.ifs
= get_local_var_value("IFS");
5272 #if ENABLE_HUSH_INTERACTIVE
5273 input
->promptmode
= 0; /* PS1 */
5275 /* dest.o_assignment = MAYBE_ASSIGNMENT; - already is */
5276 initialize_context(&ctx
);
5281 const char *is_special
;
5285 redir_type redir_style
;
5288 /* dest.o_quoted = 1; - already is (see below) */
5289 if (parse_stream_dquoted(&ctx
.as_string
, &dest
, input
, '"')) {
5292 /* We reached closing '"' */
5295 ch
= i_getch(input
);
5296 debug_printf_parse(": ch=%c (%d) escape=%d\n",
5297 ch
, ch
, dest
.o_escape
);
5302 syntax_error_unterm_str("here document");
5305 if (done_word(&dest
, &ctx
)) {
5309 done_pipe(&ctx
, PIPE_SEQ
);
5311 /* If we got nothing... */
5312 /* (this makes bare "&" cmd a no-op.
5313 * bash says: "syntax error near unexpected token '&'") */
5314 if (pi
->num_cmds
== 0
5315 IF_HAS_KEYWORDS( && pi
->res_word
== RES_NONE
)
5321 debug_printf_parse("as_string '%s'\n", ctx
.as_string
.data
);
5323 *pstring
= ctx
.as_string
.data
;
5325 o_free_unsafe(&ctx
.as_string
);
5328 debug_printf_parse("parse_stream return %p\n", pi
);
5331 nommu_addchr(&ctx
.as_string
, ch
);
5332 is_ifs
= strchr(G
.ifs
, ch
);
5333 is_special
= strchr("<>;&|(){}#'" /* special outside of "str" */
5334 "\\$\"" USE_HUSH_TICK("`") /* always special */
5337 if (!is_special
&& !is_ifs
) { /* ordinary char */
5338 o_addQchr(&dest
, ch
);
5339 if ((dest
.o_assignment
== MAYBE_ASSIGNMENT
5340 || dest
.o_assignment
== WORD_IS_KEYWORD
)
5342 && is_well_formed_var_name(dest
.data
, '=')
5344 dest
.o_assignment
= DEFINITELY_ASSIGNMENT
;
5350 if (done_word(&dest
, &ctx
)) {
5354 #if ENABLE_HUSH_CASE
5355 /* "case ... in <newline> word) ..." -
5356 * newlines are ignored (but ';' wouldn't be) */
5357 if (ctx
.command
->argv
== NULL
5358 && ctx
.ctx_res_w
== RES_MATCH
5363 /* Treat newline as a command separator. */
5364 done_pipe(&ctx
, PIPE_SEQ
);
5365 debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt
);
5367 if (fetch_heredocs(heredoc_cnt
, &ctx
, input
)) {
5372 dest
.o_assignment
= MAYBE_ASSIGNMENT
;
5374 /* note: if (is_ifs) continue;
5375 * will still trigger for us */
5378 if (end_trigger
&& end_trigger
== ch
5379 && (heredoc_cnt
== 0 || end_trigger
!= ';')
5381 //TODO: disallow "{ cmd }" without semicolon
5383 /* This is technically valid:
5384 * { cat <<HERE; }; echo Ok
5389 * but we don't support this.
5390 * We require heredoc to be in enclosing {}/(),
5393 syntax_error_unterm_str("here document");
5396 if (done_word(&dest
, &ctx
)) {
5399 done_pipe(&ctx
, PIPE_SEQ
);
5400 dest
.o_assignment
= MAYBE_ASSIGNMENT
;
5401 /* Do we sit outside of any if's, loops or case's? */
5403 IF_HAS_KEYWORDS(|| (ctx
.ctx_res_w
== RES_NONE
&& ctx
.old_flag
== 0))
5407 debug_printf_parse("as_string '%s'\n", ctx
.as_string
.data
);
5409 *pstring
= ctx
.as_string
.data
;
5411 o_free_unsafe(&ctx
.as_string
);
5414 debug_printf_parse("parse_stream return %p: "
5415 "end_trigger char found\n",
5417 return ctx
.list_head
;
5425 next
= i_peek(input
);
5428 /* Catch <, > before deciding whether this word is
5429 * an assignment. a=1 2>z b=2: b=2 is still assignment */
5432 redir_fd
= redirect_opt_num(&dest
);
5433 if (done_word(&dest
, &ctx
)) {
5436 redir_style
= REDIRECT_OVERWRITE
;
5438 redir_style
= REDIRECT_APPEND
;
5439 ch
= i_getch(input
);
5440 nommu_addchr(&ctx
.as_string
, ch
);
5443 else if (next
== '(') {
5444 syntax_error(">(process) not supported");
5448 if (parse_redirect(&ctx
, redir_fd
, redir_style
, input
))
5450 continue; /* back to top of while (1) */
5452 redir_fd
= redirect_opt_num(&dest
);
5453 if (done_word(&dest
, &ctx
)) {
5456 redir_style
= REDIRECT_INPUT
;
5458 redir_style
= REDIRECT_HEREDOC
;
5460 debug_printf_parse("++heredoc_cnt=%d\n", heredoc_cnt
);
5461 ch
= i_getch(input
);
5462 nommu_addchr(&ctx
.as_string
, ch
);
5463 } else if (next
== '>') {
5464 redir_style
= REDIRECT_IO
;
5465 ch
= i_getch(input
);
5466 nommu_addchr(&ctx
.as_string
, ch
);
5469 else if (next
== '(') {
5470 syntax_error("<(process) not supported");
5474 if (parse_redirect(&ctx
, redir_fd
, redir_style
, input
))
5476 continue; /* back to top of while (1) */
5479 if (dest
.o_assignment
== MAYBE_ASSIGNMENT
5480 /* check that we are not in word in "a=1 2>word b=1": */
5481 && !ctx
.pending_redirect
5483 /* ch is a special char and thus this word
5484 * cannot be an assignment */
5485 dest
.o_assignment
= NOT_ASSIGNMENT
;
5490 if (dest
.length
== 0) {
5493 if (ch
== EOF
|| ch
== '\n')
5496 /* note: we do not add it to &ctx.as_string */
5498 nommu_addchr(&ctx
.as_string
, '\n');
5500 o_addQchr(&dest
, ch
);
5505 syntax_error("\\<eof>");
5508 o_addchr(&dest
, '\\');
5509 ch
= i_getch(input
);
5510 nommu_addchr(&ctx
.as_string
, ch
);
5511 o_addchr(&dest
, ch
);
5512 /* Example: echo Hello \2>file
5513 * we need to know that word 2 is quoted */
5517 if (handle_dollar(&ctx
.as_string
, &dest
, input
) != 0) {
5518 debug_printf_parse("parse_stream parse error: "
5519 "handle_dollar returned non-0\n");
5526 ch
= i_getch(input
);
5528 syntax_error_unterm_ch('\'');
5529 /*xfunc_die(); - redundant */
5531 nommu_addchr(&ctx
.as_string
, ch
);
5534 if (dest
.o_assignment
== NOT_ASSIGNMENT
)
5535 o_addqchr(&dest
, ch
);
5537 o_addchr(&dest
, ch
);
5542 is_in_dquote
^= 1; /* invert */
5543 if (dest
.o_assignment
== NOT_ASSIGNMENT
)
5546 #if ENABLE_HUSH_TICK
5551 o_addchr(&dest
, SPECIAL_VAR_SYMBOL
);
5552 o_addchr(&dest
, '`');
5556 add_till_backquote(&dest
, input
);
5558 o_addstr(&ctx
.as_string
, dest
.data
+ pos
);
5559 o_addchr(&ctx
.as_string
, '`');
5561 o_addchr(&dest
, SPECIAL_VAR_SYMBOL
);
5562 //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos);
5567 #if ENABLE_HUSH_CASE
5570 if (done_word(&dest
, &ctx
)) {
5573 done_pipe(&ctx
, PIPE_SEQ
);
5574 #if ENABLE_HUSH_CASE
5575 /* Eat multiple semicolons, detect
5576 * whether it means something special */
5581 ch
= i_getch(input
);
5582 nommu_addchr(&ctx
.as_string
, ch
);
5583 if (ctx
.ctx_res_w
== RES_CASEI
) {
5584 ctx
.ctx_dsemicolon
= 1;
5585 ctx
.ctx_res_w
= RES_MATCH
;
5591 /* We just finished a cmd. New one may start
5592 * with an assignment */
5593 dest
.o_assignment
= MAYBE_ASSIGNMENT
;
5596 if (done_word(&dest
, &ctx
)) {
5600 ch
= i_getch(input
);
5601 nommu_addchr(&ctx
.as_string
, ch
);
5602 done_pipe(&ctx
, PIPE_AND
);
5604 done_pipe(&ctx
, PIPE_BG
);
5608 if (done_word(&dest
, &ctx
)) {
5611 #if ENABLE_HUSH_CASE
5612 if (ctx
.ctx_res_w
== RES_MATCH
)
5613 break; /* we are in case's "word | word)" */
5615 if (next
== '|') { /* || */
5616 ch
= i_getch(input
);
5617 nommu_addchr(&ctx
.as_string
, ch
);
5618 done_pipe(&ctx
, PIPE_OR
);
5620 /* we could pick up a file descriptor choice here
5621 * with redirect_opt_num(), but bash doesn't do it.
5622 * "echo foo 2| cat" yields "foo 2". */
5627 #if ENABLE_HUSH_CASE
5628 /* "case... in [(]word)..." - skip '(' */
5629 if (ctx
.ctx_res_w
== RES_MATCH
5630 && ctx
.command
->argv
== NULL
/* not (word|(... */
5631 && dest
.length
== 0 /* not word(... */
5632 && dest
.o_quoted
== 0 /* not ""(... */
5638 if (parse_group(&dest
, &ctx
, input
, ch
) != 0) {
5643 #if ENABLE_HUSH_CASE
5644 if (ctx
.ctx_res_w
== RES_MATCH
)
5648 /* proper use of this character is caught by end_trigger:
5649 * if we see {, we call parse_group(..., end_trigger='}')
5650 * and it will match } earlier (not here). */
5651 syntax_error_unexpected_ch(ch
);
5655 bb_error_msg_and_die("BUG: unexpected %c\n", ch
);
5661 struct parse_context
*pctx
;
5662 IF_HAS_KEYWORDS(struct parse_context
*p2
;)
5664 /* Clean up allocated tree.
5665 * Samples for finding leaks on syntax error recovery path.
5666 * Run them from interactive shell, watch pmap `pidof hush`.
5667 * while if false; then false; fi do break; done
5669 * while if false; then false; fi; do break; fi
5670 * Samples to catch leaks at execution:
5671 * while if (true | {true;}); then echo ok; fi; do break; done
5672 * while if (true | {true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
5676 /* Update pipe/command counts,
5677 * otherwise freeing may miss some */
5678 done_pipe(pctx
, PIPE_SEQ
);
5679 debug_printf_clean("freeing list %p from ctx %p\n",
5680 pctx
->list_head
, pctx
);
5681 debug_print_tree(pctx
->list_head
, 0);
5682 free_pipe_list(pctx
->list_head
);
5683 debug_printf_clean("freed list %p\n", pctx
->list_head
);
5685 o_free_unsafe(&pctx
->as_string
);
5687 IF_HAS_KEYWORDS(p2
= pctx
->stack
;)
5691 IF_HAS_KEYWORDS(pctx
= p2
;)
5692 } while (HAS_KEYWORDS
&& pctx
);
5693 /* Free text, clear all dest fields */
5695 /* If we are not in top-level parse, we return,
5696 * our caller will propagate error.
5698 if (end_trigger
!= ';') {
5706 /* Discard cached input, force prompt */
5708 USE_HUSH_INTERACTIVE(input
->promptme
= 1;)
5713 /* Executing from string: eval, sh -c '...'
5714 * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
5715 * end_trigger controls how often we stop parsing
5716 * NUL: parse all, execute, return
5717 * ';': parse till ';' or newline, execute, repeat till EOF
5719 static void parse_and_run_stream(struct in_str
*inp
, int end_trigger
)
5722 struct pipe
*pipe_list
;
5724 pipe_list
= parse_stream(NULL
, inp
, end_trigger
);
5725 if (!pipe_list
) /* EOF */
5727 debug_print_tree(pipe_list
, 0);
5728 debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
5729 run_and_free_list(pipe_list
);
5733 static void parse_and_run_string(const char *s
)
5735 struct in_str input
;
5736 setup_string_in_str(&input
, s
);
5737 parse_and_run_stream(&input
, '\0');
5740 static void parse_and_run_file(FILE *f
)
5742 struct in_str input
;
5743 setup_file_in_str(&input
, f
);
5744 parse_and_run_stream(&input
, ';');
5747 /* Called a few times only (or even once if "sh -c") */
5748 static void block_signals(int second_time
)
5753 mask
= (1 << SIGQUIT
);
5754 if (G_interactive_fd
) {
5758 //TODO | (1 << SIGHUP)
5760 | (1 << SIGTTIN
) | (1 << SIGTTOU
) | (1 << SIGTSTP
)
5765 G
.non_DFL_mask
= mask
;
5768 sigprocmask(SIG_SETMASK
, NULL
, &G
.blocked_set
);
5772 sigaddset(&G
.blocked_set
, sig
);
5776 sigdelset(&G
.blocked_set
, SIGCHLD
);
5778 sigprocmask(SIG_SETMASK
, &G
.blocked_set
,
5779 second_time
? NULL
: &G
.inherited_set
);
5780 /* POSIX allows shell to re-enable SIGCHLD
5781 * even if it was SIG_IGN on entry */
5782 // G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
5784 signal(SIGCHLD
, SIG_DFL
); // SIGCHLD_handler);
5789 static void maybe_set_to_sigexit(int sig
)
5791 void (*handler
)(int);
5792 /* non_DFL_mask'ed signals are, well, masked,
5793 * no need to set handler for them.
5795 if (!((G
.non_DFL_mask
>> sig
) & 1)) {
5796 handler
= signal(sig
, sigexit
);
5797 if (handler
== SIG_IGN
) /* oops... restore back to IGN! */
5798 signal(sig
, handler
);
5801 /* Set handlers to restore tty pgrp and exit */
5802 static void set_fatal_handlers(void)
5804 /* We _must_ restore tty pgrp on fatal signals */
5806 maybe_set_to_sigexit(SIGILL
);
5807 maybe_set_to_sigexit(SIGFPE
);
5808 maybe_set_to_sigexit(SIGBUS
);
5809 maybe_set_to_sigexit(SIGSEGV
);
5810 maybe_set_to_sigexit(SIGTRAP
);
5811 } /* else: hush is perfect. what SEGV? */
5812 maybe_set_to_sigexit(SIGABRT
);
5813 /* bash 3.2 seems to handle these just like 'fatal' ones */
5814 maybe_set_to_sigexit(SIGPIPE
);
5815 maybe_set_to_sigexit(SIGALRM
);
5816 //TODO: disable and move down when proper SIGHUP handling is added
5817 maybe_set_to_sigexit(SIGHUP
);
5818 /* if we are interactive, [SIGHUP,] SIGTERM and SIGINT are masked.
5819 * if we aren't interactive... but in this case
5820 * we never want to restore pgrp on exit, and this fn is not called */
5821 /*maybe_set_to_sigexit(SIGTERM);*/
5822 /*maybe_set_to_sigexit(SIGINT );*/
5826 static int set_mode(const char cstate
, const char mode
)
5828 int state
= (cstate
== '-' ? 1 : 0);
5830 case 'n': G
.fake_mode
= state
; break;
5831 case 'x': /*G.debug_mode = state;*/ break;
5832 default: return EXIT_FAILURE
;
5834 return EXIT_SUCCESS
;
5837 int hush_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
5838 int hush_main(int argc
, char **argv
)
5840 static const struct variable const_shell_ver
= {
5842 .varstr
= (char*)hush_version_str
,
5843 .max_len
= 1, /* 0 can provoke free(name) */
5847 int signal_mask_is_inited
= 0;
5850 struct variable
*cur_var
;
5853 if (EXIT_SUCCESS
) /* if EXIT_SUCCESS == 0, is already done */
5854 G
.last_exitcode
= EXIT_SUCCESS
;
5856 G
.argv0_for_re_execing
= argv
[0];
5858 /* Deal with HUSH_VERSION */
5859 G
.shell_ver
= const_shell_ver
; /* copying struct here */
5860 G
.top_var
= &G
.shell_ver
;
5861 debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
5862 unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
5863 /* Initialize our shell local variables with the values
5864 * currently living in the environment */
5865 cur_var
= G
.top_var
;
5868 char *value
= strchr(*e
, '=');
5869 if (value
) { /* paranoia */
5870 cur_var
->next
= xzalloc(sizeof(*cur_var
));
5871 cur_var
= cur_var
->next
;
5872 cur_var
->varstr
= *e
;
5873 cur_var
->max_len
= strlen(*e
);
5874 cur_var
->flg_export
= 1;
5878 debug_printf_env("putenv '%s'\n", hush_version_str
);
5879 putenv((char *)hush_version_str
); /* reinstate HUSH_VERSION */
5880 #if ENABLE_FEATURE_EDITING
5881 G
.line_input_state
= new_line_input_t(FOR_SHELL
);
5883 G
.global_argc
= argc
;
5884 G
.global_argv
= argv
;
5885 /* Initialize some more globals to non-zero values */
5887 #if ENABLE_HUSH_INTERACTIVE
5888 if (ENABLE_FEATURE_EDITING
)
5889 cmdedit_set_initial_prompt();
5893 if (setjmp(die_jmp
)) {
5894 /* xfunc has failed! die die die */
5895 /* no EXIT traps, this is an escape hatch! */
5897 hush_exit(xfunc_error_retval
);
5900 /* Shell is non-interactive at first. We need to call
5901 * block_signals(0) if we are going to execute "sh <script>",
5902 * "sh -c <cmds>" or login shell's /etc/profile and friends.
5903 * If we later decide that we are interactive, we run block_signals(0)
5904 * (or re-run block_signals(1) if we ran block_signals(0) before)
5905 * in order to intercept (more) signals.
5909 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */
5911 opt
= getopt(argc
, argv
, "c:xins"
5914 # if ENABLE_HUSH_FUNCTIONS
5924 G
.root_pid
= getpid();
5925 G
.global_argv
= argv
+ optind
;
5926 if (!argv
[optind
]) {
5927 /* -c 'script' (no params): prevent empty $0 */
5928 *--G
.global_argv
= argv
[0];
5930 } /* else -c 'script' PAR0 PAR1: $0 is PAR0 */
5931 G
.global_argc
= argc
- optind
;
5932 block_signals(0); /* 0: called 1st time */
5933 parse_and_run_string(optarg
);
5936 /* Well, we cannot just declare interactiveness,
5937 * we have to have some stuff (ctty, etc) */
5938 /* G_interactive_fd++; */
5941 /* "-s" means "read from stdin", but this is how we always
5942 * operate, so simply do nothing here. */
5945 case '<': /* "big heredoc" support */
5946 full_write(STDOUT_FILENO
, optarg
, strlen(optarg
));
5949 G
.root_pid
= bb_strtou(optarg
, &optarg
, 16);
5951 G
.last_bg_pid
= bb_strtou(optarg
, &optarg
, 16);
5953 G
.last_exitcode
= bb_strtou(optarg
, &optarg
, 16);
5954 # if ENABLE_HUSH_LOOPS
5956 G
.depth_of_loop
= bb_strtou(optarg
, &optarg
, 16);
5961 set_local_var(xstrdup(optarg
), 0, opt
== 'R');
5963 # if ENABLE_HUSH_FUNCTIONS
5965 struct function
*funcp
= new_function(optarg
);
5966 /* funcp->name is already set to optarg */
5967 /* funcp->body is set to NULL. It's a special case. */
5968 funcp
->body_as_string
= argv
[optind
];
5976 if (!set_mode('-', opt
))
5980 fprintf(stderr
, "Usage: sh [FILE]...\n"
5981 " or: sh -c command [args]...\n\n");
5987 } /* option parsing loop */
5990 G
.root_pid
= getpid();
5992 /* If we are login shell... */
5993 if (argv
[0] && argv
[0][0] == '-') {
5995 /* XXX what should argv be while sourcing /etc/profile? */
5996 debug_printf("sourcing /etc/profile\n");
5997 input
= fopen_for_read("/etc/profile");
5998 if (input
!= NULL
) {
5999 close_on_exec_on(fileno(input
));
6000 block_signals(0); /* 0: called 1st time */
6001 signal_mask_is_inited
= 1;
6002 parse_and_run_file(input
);
6005 /* bash: after sourcing /etc/profile,
6006 * tries to source (in the given order):
6007 * ~/.bash_profile, ~/.bash_login, ~/.profile,
6008 * stopping of first found. --noprofile turns this off.
6009 * bash also sources ~/.bash_logout on exit.
6010 * If called as sh, skips .bash_XXX files.
6017 * "bash <script>" (which is never interactive (unless -i?))
6018 * sources $BASH_ENV here (without scanning $PATH).
6019 * If called as sh, does the same but with $ENV.
6021 debug_printf("running script '%s'\n", argv
[optind
]);
6022 G
.global_argv
= argv
+ optind
;
6023 G
.global_argc
= argc
- optind
;
6024 input
= xfopen_for_read(argv
[optind
]);
6025 close_on_exec_on(fileno(input
));
6026 if (!signal_mask_is_inited
)
6027 block_signals(0); /* 0: called 1st time */
6028 parse_and_run_file(input
);
6029 #if ENABLE_FEATURE_CLEAN_UP
6035 /* Up to here, shell was non-interactive. Now it may become one.
6036 * NB: don't forget to (re)run block_signals(0/1) as needed.
6039 /* A shell is interactive if the '-i' flag was given, or if all of
6040 * the following conditions are met:
6042 * no arguments remaining or the -s flag given
6043 * standard input is a terminal
6044 * standard output is a terminal
6045 * Refer to Posix.2, the description of the 'sh' utility.
6048 if (isatty(STDIN_FILENO
) && isatty(STDOUT_FILENO
)) {
6049 G
.saved_tty_pgrp
= tcgetpgrp(STDIN_FILENO
);
6050 debug_printf("saved_tty_pgrp:%d\n", G
.saved_tty_pgrp
);
6051 //TODO: "interactive" and "have job control" are two different things.
6052 //If tcgetpgrp fails here, "have job control" is false, but "interactive"
6053 //should stay on! Currently, we mix these into one.
6054 if (G
.saved_tty_pgrp
>= 0) {
6055 /* try to dup stdin to high fd#, >= 255 */
6056 G_interactive_fd
= fcntl(STDIN_FILENO
, F_DUPFD
, 255);
6057 if (G_interactive_fd
< 0) {
6058 /* try to dup to any fd */
6059 G_interactive_fd
= dup(STDIN_FILENO
);
6060 if (G_interactive_fd
< 0)
6062 G_interactive_fd
= 0;
6064 // TODO: track & disallow any attempts of user
6065 // to (inadvertently) close/redirect it
6068 debug_printf("interactive_fd:%d\n", G_interactive_fd
);
6069 if (G_interactive_fd
) {
6072 /* We are indeed interactive shell, and we will perform
6073 * job control. Setting up for that. */
6075 close_on_exec_on(G_interactive_fd
);
6076 /* If we were run as 'hush &', sleep until we are
6077 * in the foreground (tty pgrp == our pgrp).
6078 * If we get started under a job aware app (like bash),
6079 * make sure we are now in charge so we don't fight over
6080 * who gets the foreground */
6082 shell_pgrp
= getpgrp();
6083 G
.saved_tty_pgrp
= tcgetpgrp(G_interactive_fd
);
6084 if (G
.saved_tty_pgrp
== shell_pgrp
)
6086 /* send TTIN to ourself (should stop us) */
6087 kill(- shell_pgrp
, SIGTTIN
);
6089 /* Block some signals */
6090 block_signals(signal_mask_is_inited
);
6091 /* Set other signals to restore saved_tty_pgrp */
6092 set_fatal_handlers();
6093 /* Put ourselves in our own process group */
6094 bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
6095 /* Grab control of the terminal */
6096 tcsetpgrp(G_interactive_fd
, getpid());
6097 /* -1 is special - makes xfuncs longjmp, not exit
6098 * (we reset die_sleep = 0 whereever we [v]fork) */
6099 enable_restore_tty_pgrp_on_exit(); /* sets die_sleep = -1 */
6100 } else if (!signal_mask_is_inited
) {
6101 block_signals(0); /* 0: called 1st time */
6102 } /* else: block_signals(0) was done before */
6103 #elif ENABLE_HUSH_INTERACTIVE
6104 /* No job control compiled in, only prompt/line editing */
6105 if (isatty(STDIN_FILENO
) && isatty(STDOUT_FILENO
)) {
6106 G_interactive_fd
= fcntl(STDIN_FILENO
, F_DUPFD
, 255);
6107 if (G_interactive_fd
< 0) {
6108 /* try to dup to any fd */
6109 G_interactive_fd
= dup(STDIN_FILENO
);
6110 if (G_interactive_fd
< 0)
6112 G_interactive_fd
= 0;
6115 if (G_interactive_fd
) {
6116 close_on_exec_on(G_interactive_fd
);
6117 block_signals(signal_mask_is_inited
);
6118 } else if (!signal_mask_is_inited
) {
6122 /* We have interactiveness code disabled */
6123 if (!signal_mask_is_inited
) {
6128 * if interactive but not a login shell, sources ~/.bashrc
6129 * (--norc turns this off, --rcfile <file> overrides)
6132 if (!ENABLE_FEATURE_SH_EXTRA_QUIET
&& G_interactive_fd
) {
6133 printf("\n\n%s hush - the humble shell\n", bb_banner
);
6134 printf("Enter 'help' for a list of built-in commands.\n\n");
6137 parse_and_run_file(stdin
);
6140 #if ENABLE_FEATURE_CLEAN_UP
6141 if (G
.cwd
!= bb_msg_unknown
)
6143 cur_var
= G
.top_var
->next
;
6145 struct variable
*tmp
= cur_var
;
6146 if (!cur_var
->max_len
)
6147 free(cur_var
->varstr
);
6148 cur_var
= cur_var
->next
;
6152 hush_exit(G
.last_exitcode
);
6157 int lash_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
6158 int lash_main(int argc
, char **argv
)
6160 //bb_error_msg("lash is deprecated, please use hush instead");
6161 return hush_main(argc
, argv
);
6169 static int builtin_trap(char **argv
)
6176 G
.traps
= xzalloc(sizeof(G
.traps
[0]) * NSIG
);
6180 /* No args: print all trapped. This isn't 100% correct as we
6181 * should be escaping the cmd so that it can be pasted back in
6183 for (i
= 0; i
< NSIG
; ++i
)
6185 printf("trap -- '%s' %s\n", G
.traps
[i
], get_signame(i
));
6186 return EXIT_SUCCESS
;
6191 /* If first arg is decimal: reset all specified signals */
6192 sig
= bb_strtou(*argv
, NULL
, 10);
6198 sig
= get_signum(*argv
++);
6199 if (sig
< 0 || sig
>= NSIG
) {
6201 /* Mimic bash message exactly */
6202 bb_perror_msg("trap: %s: invalid signal specification", argv
[i
]);
6207 G
.traps
[sig
] = xstrdup(new_cmd
);
6209 debug_printf("trap: setting SIG%s (%i) to '%s'",
6210 get_signame(sig
), sig
, G
.traps
[sig
]);
6212 /* There is no signal for 0 (EXIT) */
6217 sigaddset(&G
.blocked_set
, sig
);
6219 /* There was a trap handler, we are removing it
6220 * (if sig has non-DFL handling,
6221 * we don't need to do anything) */
6222 if (sig
< 32 && (G
.non_DFL_mask
& (1 << sig
)))
6224 sigdelset(&G
.blocked_set
, sig
);
6226 sigprocmask(SIG_SETMASK
, &G
.blocked_set
, NULL
);
6231 /* First arg is "-": reset all specified to default */
6232 /* First arg is "": ignore all specified */
6233 /* Everything else: execute first arg upon signal */
6235 bb_error_msg("trap: invalid arguments");
6236 return EXIT_FAILURE
;
6238 if (NOT_LONE_DASH(*argv
))
6244 static int builtin_true(char **argv UNUSED_PARAM
)
6249 static int builtin_test(char **argv
)
6256 return test_main(argc
, argv
- argc
);
6259 static int builtin_echo(char **argv
)
6266 return echo_main(argc
, argv
- argc
);
6269 static int builtin_eval(char **argv
)
6271 int rcode
= EXIT_SUCCESS
;
6274 char *str
= expand_strvec_to_string(argv
);
6276 * eval "echo Hi; done" ("done" is syntax error):
6277 * "echo Hi" will not execute too.
6279 parse_and_run_string(str
);
6281 rcode
= G
.last_exitcode
;
6286 static int builtin_cd(char **argv
)
6288 const char *newdir
= argv
[1];
6289 if (newdir
== NULL
) {
6290 /* bash does nothing (exitcode 0) if HOME is ""; if it's unset,
6291 * bash says "bash: cd: HOME not set" and does nothing
6294 newdir
= getenv("HOME") ? : "/";
6296 if (chdir(newdir
)) {
6297 /* Mimic bash message exactly */
6298 bb_perror_msg("cd: %s", newdir
);
6299 return EXIT_FAILURE
;
6302 return EXIT_SUCCESS
;
6305 static int builtin_exec(char **argv
)
6307 if (*++argv
== NULL
)
6308 return EXIT_SUCCESS
; /* bash does this */
6313 // FIXME: if exec fails, bash does NOT exit! We do...
6314 pseudo_exec_argv(&dummy
, argv
, 0, NULL
);
6319 static int builtin_exit(char **argv
)
6321 debug_printf_exec("%s()\n", __func__
);
6322 // TODO: bash does it ONLY on top-level sh exit (+interacive only?)
6323 //puts("exit"); /* bash does it */
6324 // TODO: warn if we have background jobs: "There are stopped jobs"
6325 // On second consecutive 'exit', exit anyway.
6326 // perhaps use G.exiting = -1 as indicator "last cmd was exit"
6328 /* note: EXIT trap is run by hush_exit */
6329 if (*++argv
== NULL
)
6330 hush_exit(G
.last_exitcode
);
6331 /* mimic bash: exit 123abc == exit 255 + error msg */
6332 xfunc_error_retval
= 255;
6333 /* bash: exit -2 == exit 254, no error msg */
6334 hush_exit(xatoi(*argv
) & 0xff);
6337 static int builtin_export(char **argv
)
6339 if (*++argv
== NULL
) {
6346 /* ash emits: export VAR='VAL'
6347 * bash: declare -x VAR="VAL"
6348 * we follow ash example */
6349 const char *s
= *e
++;
6350 const char *p
= strchr(s
, '=');
6352 if (!p
) /* wtf? take next variable */
6355 printf("export %.*s", (int)(p
- s
) + 1, s
);
6359 p
= strchrnul(s
, '\'');
6361 printf("'%.*s'", (int)(p
- s
), s
);
6366 /* s points to '; print ''...'''" */
6368 do putchar('\''); while (*++s
== '\'');
6376 return EXIT_SUCCESS
;
6383 value
= strchr(name
, '=');
6385 /* They are exporting something without a =VALUE */
6386 struct variable
*var
;
6388 var
= get_local_var(name
);
6390 var
->flg_export
= 1;
6391 debug_printf_env("%s: putenv '%s'\n", __func__
, var
->varstr
);
6392 putenv(var
->varstr
);
6394 /* bash does not return an error when trying to export
6395 * an undefined variable. Do likewise. */
6398 set_local_var(xstrdup(name
), 1, 0);
6401 return EXIT_SUCCESS
;
6405 /* built-in 'fg' and 'bg' handler */
6406 static int builtin_fg_bg(char **argv
)
6411 if (!G_interactive_fd
)
6412 return EXIT_FAILURE
;
6413 /* If they gave us no args, assume they want the last backgrounded task */
6415 for (pi
= G
.job_list
; pi
; pi
= pi
->next
) {
6416 if (pi
->jobid
== G
.last_jobid
) {
6420 bb_error_msg("%s: no current job", argv
[0]);
6421 return EXIT_FAILURE
;
6423 if (sscanf(argv
[1], "%%%d", &jobnum
) != 1) {
6424 bb_error_msg("%s: bad argument '%s'", argv
[0], argv
[1]);
6425 return EXIT_FAILURE
;
6427 for (pi
= G
.job_list
; pi
; pi
= pi
->next
) {
6428 if (pi
->jobid
== jobnum
) {
6432 bb_error_msg("%s: %d: no such job", argv
[0], jobnum
);
6433 return EXIT_FAILURE
;
6435 // TODO: bash prints a string representation
6436 // of job being foregrounded (like "sleep 1 | cat")
6437 if (argv
[0][0] == 'f') {
6438 /* Put the job into the foreground. */
6439 tcsetpgrp(G_interactive_fd
, pi
->pgrp
);
6442 /* Restart the processes in the job */
6443 debug_printf_jobs("reviving %d procs, pgrp %d\n", pi
->num_cmds
, pi
->pgrp
);
6444 for (i
= 0; i
< pi
->num_cmds
; i
++) {
6445 debug_printf_jobs("reviving pid %d\n", pi
->cmds
[i
].pid
);
6446 pi
->cmds
[i
].is_stopped
= 0;
6448 pi
->stopped_cmds
= 0;
6450 i
= kill(- pi
->pgrp
, SIGCONT
);
6452 if (errno
== ESRCH
) {
6453 delete_finished_bg_job(pi
);
6454 return EXIT_SUCCESS
;
6456 bb_perror_msg("kill (SIGCONT)");
6459 if (argv
[0][0] == 'f') {
6461 return checkjobs_and_fg_shell(pi
);
6463 return EXIT_SUCCESS
;
6467 #if ENABLE_HUSH_HELP
6468 static int builtin_help(char **argv UNUSED_PARAM
)
6470 const struct built_in_command
*x
;
6473 "Built-in commands:\n"
6474 "------------------\n");
6475 for (x
= bltins
; x
!= &bltins
[ARRAY_SIZE(bltins
)]; x
++) {
6476 printf("%s\t%s\n", x
->cmd
, x
->descr
);
6479 return EXIT_SUCCESS
;
6484 static int builtin_jobs(char **argv UNUSED_PARAM
)
6487 const char *status_string
;
6489 for (job
= G
.job_list
; job
; job
= job
->next
) {
6490 if (job
->alive_cmds
== job
->stopped_cmds
)
6491 status_string
= "Stopped";
6493 status_string
= "Running";
6495 printf(JOB_STATUS_FORMAT
, job
->jobid
, status_string
, job
->cmdtext
);
6497 return EXIT_SUCCESS
;
6502 static int builtin_memleak(char **argv UNUSED_PARAM
)
6507 /* Crude attempt to find where "free memory" starts,
6508 * sans fragmentation. */
6510 l
= (unsigned long)p
;
6513 if (l
< (unsigned long)p
) l
= (unsigned long)p
;
6516 if (!G
.memleak_value
)
6517 G
.memleak_value
= l
;
6519 l
-= G
.memleak_value
;
6526 /* Exitcode is "how many kilobytes we leaked since 1st call" */
6531 static int builtin_pwd(char **argv UNUSED_PARAM
)
6534 return EXIT_SUCCESS
;
6537 static int builtin_read(char **argv
)
6540 const char *name
= "REPLY";
6544 /* bash (3.2.33(1)) bug: "read 0abcd" will execute,
6545 * and _after_ that_ it will complain */
6546 if (!is_well_formed_var_name(name
, '\0')) {
6547 /* Mimic bash message */
6548 bb_error_msg("read: '%s': not a valid identifier", name
);
6553 //TODO: bash unbackslashes input, splits words and puts them in argv[i]
6555 string
= xmalloc_reads(STDIN_FILENO
, xasprintf("%s=", name
), NULL
);
6556 return set_local_var(string
, 0, 0);
6559 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
6560 * built-in 'set' handler
6562 * set [-abCefhmnuvx] [-o option] [argument...]
6563 * set [+abCefhmnuvx] [+o option] [argument...]
6564 * set -- [argument...]
6567 * Implementations shall support the options in both their hyphen and
6568 * plus-sign forms. These options can also be specified as options to sh.
6570 * Write out all variables and their values: set
6571 * Set $1, $2, and $3 and set "$#" to 3: set c a b
6572 * Turn on the -x and -v options: set -xv
6573 * Unset all positional parameters: set --
6574 * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x"
6575 * Set the positional parameters to the expansion of x, even if x expands
6576 * with a leading '-' or '+': set -- $x
6578 * So far, we only support "set -- [argument...]" and some of the short names.
6580 static int builtin_set(char **argv
)
6583 char **pp
, **g_argv
;
6584 char *arg
= *++argv
;
6588 for (e
= G
.top_var
; e
; e
= e
->next
)
6590 return EXIT_SUCCESS
;
6594 if (!strcmp(arg
, "--")) {
6598 if (arg
[0] != '+' && arg
[0] != '-')
6600 for (n
= 1; arg
[n
]; ++n
)
6601 if (set_mode(arg
[0], arg
[n
]))
6603 } while ((arg
= *++argv
) != NULL
);
6604 /* Now argv[0] is 1st argument */
6607 return EXIT_SUCCESS
;
6610 /* NB: G.global_argv[0] ($0) is never freed/changed */
6611 g_argv
= G
.global_argv
;
6612 if (G
.global_args_malloced
) {
6618 G
.global_args_malloced
= 1;
6619 pp
= xzalloc(sizeof(pp
[0]) * 2);
6620 pp
[0] = g_argv
[0]; /* retain $0 */
6623 /* This realloc's G.global_argv */
6624 G
.global_argv
= pp
= add_strings_to_strings(g_argv
, argv
, /*dup:*/ 1);
6631 return EXIT_SUCCESS
;
6633 /* Nothing known, so abort */
6635 bb_error_msg("set: %s: invalid option", arg
);
6636 return EXIT_FAILURE
;
6639 static int builtin_shift(char **argv
)
6645 if (n
>= 0 && n
< G
.global_argc
) {
6646 if (G
.global_args_malloced
) {
6649 free(G
.global_argv
[m
++]);
6652 memmove(&G
.global_argv
[1], &G
.global_argv
[n
+1],
6653 G
.global_argc
* sizeof(G
.global_argv
[0]));
6654 return EXIT_SUCCESS
;
6656 return EXIT_FAILURE
;
6659 static int builtin_source(char **argv
)
6663 if (*++argv
== NULL
)
6664 return EXIT_FAILURE
;
6666 /* XXX search through $PATH is missing */
6667 input
= fopen_or_warn(*argv
, "r");
6669 /* bb_perror_msg("%s", *argv); - done by fopen_or_warn */
6670 return EXIT_FAILURE
;
6672 close_on_exec_on(fileno(input
));
6674 /* Now run the file */
6676 /* XXX argv and argc are broken; need to save old G.global_argv
6677 * (pointer only is OK!) on this stack frame,
6678 * set G.global_argv=argv+1, recurse, and restore. */
6679 parse_and_run_file(input
);
6681 return G
.last_exitcode
;
6684 static int builtin_umask(char **argv
)
6687 const char *arg
= argv
[1];
6689 //TODO: umask may take chmod-like symbolic masks
6690 new_umask
= bb_strtou(arg
, NULL
, 8);
6692 //Message? bash examples:
6693 //bash: umask: 'q': invalid symbolic mode operator
6694 //bash: umask: 999: octal number out of range
6695 return EXIT_FAILURE
;
6698 new_umask
= umask(0);
6699 printf("%.3o\n", (unsigned) new_umask
);
6700 /* fall through and restore new_umask which we set to 0 */
6703 return EXIT_SUCCESS
;
6706 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */
6707 static int builtin_unset(char **argv
)
6713 return EXIT_SUCCESS
;
6716 if (argv
[0][0] == '-') {
6717 switch (argv
[0][1]) {
6723 bb_error_msg("unset: %s: invalid option", *argv
);
6724 return EXIT_FAILURE
;
6726 //TODO: disallow "unset -vf ..." too
6733 if (unset_local_var(*argv
)) {
6734 /* unset <nonexistent_var> doesn't fail.
6735 * Error is when one tries to unset RO var.
6736 * Message was printed by unset_local_var. */
6740 //#if ENABLE_HUSH_FUNCTIONS
6742 // unset_local_func(*argv);
6750 /* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */
6751 static int builtin_wait(char **argv
)
6753 int ret
= EXIT_SUCCESS
;
6756 if (*++argv
== NULL
) {
6757 /* Don't care about wait results */
6758 /* Note 1: must wait until there are no more children */
6759 /* Note 2: must be interruptible */
6761 * $ sleep 3 & sleep 6 & wait
6766 * $ sleep 3 & sleep 6 & wait
6770 * ^C <-- after ~4 sec from keyboard
6773 sigaddset(&G
.blocked_set
, SIGCHLD
);
6774 sigprocmask(SIG_SETMASK
, &G
.blocked_set
, NULL
);
6777 if (errno
== ECHILD
)
6779 /* Wait for SIGCHLD or any other signal of interest */
6780 /* sigtimedwait with infinite timeout: */
6781 sig
= sigwaitinfo(&G
.blocked_set
, NULL
);
6783 sig
= check_and_run_traps(sig
);
6784 if (sig
&& sig
!= SIGCHLD
) { /* see note 2 */
6790 sigdelset(&G
.blocked_set
, SIGCHLD
);
6791 sigprocmask(SIG_SETMASK
, &G
.blocked_set
, NULL
);
6795 /* This is probably buggy wrt interruptible-ness */
6797 pid_t pid
= bb_strtou(*argv
, NULL
, 10);
6799 /* mimic bash message */
6800 bb_error_msg("wait: '%s': not a pid or valid job spec", *argv
);
6801 return EXIT_FAILURE
;
6803 if (waitpid(pid
, &status
, 0) == pid
) {
6804 if (WIFSIGNALED(status
))
6805 ret
= 128 + WTERMSIG(status
);
6806 else if (WIFEXITED(status
))
6807 ret
= WEXITSTATUS(status
);
6811 bb_perror_msg("wait %s", *argv
);
6820 #if ENABLE_HUSH_LOOPS
6821 static int builtin_break(char **argv
)
6823 if (G
.depth_of_loop
== 0) {
6824 bb_error_msg("%s: only meaningful in a loop", argv
[0]);
6825 return EXIT_SUCCESS
; /* bash compat */
6827 G
.flag_break_continue
++; /* BC_BREAK = 1 */
6828 G
.depth_break_continue
= 1;
6830 G
.depth_break_continue
= bb_strtou(argv
[1], NULL
, 10);
6831 if (errno
|| !G
.depth_break_continue
|| argv
[2]) {
6832 bb_error_msg("%s: bad arguments", argv
[0]);
6833 G
.flag_break_continue
= BC_BREAK
;
6834 G
.depth_break_continue
= UINT_MAX
;
6837 if (G
.depth_of_loop
< G
.depth_break_continue
)
6838 G
.depth_break_continue
= G
.depth_of_loop
;
6839 return EXIT_SUCCESS
;
6842 static int builtin_continue(char **argv
)
6844 G
.flag_break_continue
= 1; /* BC_CONTINUE = 2 = 1+1 */
6845 return builtin_break(argv
);