1 /* buildcmd.c -- build command lines from a list of arguments.
2 Copyright (C) 1990, 91, 92, 93, 94, 2000, 2003, 2005 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
23 # if defined PROTOTYPES || (defined __STDC__ && __STDC__)
24 # define PARAMS(Args) Args
26 # define PARAMS(Args) ()
30 #if defined(HAVE_STRING_H) || defined(STDC_HEADERS)
39 /* Simulate mbrlen with mblen as best we can. */
40 # define mbstate_t int
41 # define mbrlen(s, n, ps) mblen (s, n)
50 # define _(Text) gettext (Text)
53 #define textdomain(Domain)
54 #define bindtextdomain(Package, Directory)
57 # define N_(String) gettext_noop (String)
59 /* See locate.c for explanation as to why not use (String) */
60 # define N_(String) String
64 #include <sys/param.h>
71 /* The presence of unistd.h is assumed by gnulib these days, so we
72 * might as well assume it too.
79 /* COMPAT: SYSV version defaults size (and has a max value of) to 470.
80 We try to make it as large as possible. */
81 #if !defined(ARG_MAX) && defined(_SC_ARG_MAX)
82 #define ARG_MAX sysconf (_SC_ARG_MAX)
85 #define ARG_MAX NCARGS
95 static char *mbstrstr
PARAMS ((const char *haystack
, const char *needle
));
97 /* Replace all instances of `replace_pat' in ARG with `linebuf',
98 and add the resulting string to the list of arguments for the command
100 ARGLEN is the length of ARG, not including the null.
101 LBLEN is the length of LINEBUF, not including the null.
102 PFXLEN is the length of PREFIX. Substitution is not performed on
103 the prefix. The prefix is used if the argument contains replace_pat.
105 COMPAT: insertions on the SYSV version are limited to 255 chars per line,
106 and a max of 5 occurrences of replace_pat in the initial-arguments.
107 Those restrictions do not exist here. */
110 bc_do_insert (const struct buildcmd_control
*ctl
,
111 struct buildcmd_state
*state
,
112 char *arg
, size_t arglen
,
113 const char *prefix
, size_t pfxlen
,
114 const char *linebuf
, size_t lblen
,
117 /* Temporary copy of each arg with the replace pattern replaced by the
119 static char *insertbuf
;
121 int bytes_left
= ctl
->arg_max
- 1; /* Bytes left on the command line. */
124 /* XXX: on systems lacking an upper limit for exec args, ctl->arg_max
125 * may have been set to LONG_MAX (see bc_get_arg_max()). Hence
126 * this xmalloc call may be a bad idea, especially since we are
130 insertbuf
= (char *) xmalloc (ctl
->arg_max
+ 1);
136 size_t len
; /* Length in ARG before `replace_pat'. */
137 char *s
= mbstrstr (arg
, ctl
->replace_pat
);
152 strncpy (p
, arg
, len
);
164 arglen
-= ctl
->rplen
;
170 error (1, 0, _("command too long"));
179 bc_push_arg (ctl
, state
,
180 insertbuf
, p
- insertbuf
,
186 void do_exec(const struct buildcmd_control
*ctl
,
187 struct buildcmd_state
*state
)
189 (ctl
->exec_callback
)(ctl
, state
);
193 /* Return nonzero if there would not be enough room for an additional
194 * argument. We check the total number of arguments only, not the space
195 * occupied by those arguments.
197 * If we return zero, there still may not be enough room for the next
198 * argument, depending on its length.
201 bc_argc_limit_reached(int initial_args
,
202 const struct buildcmd_control
*ctl
,
203 struct buildcmd_state
*state
)
205 /* Check to see if we about to exceed a limit set by xargs' -n option */
206 if (!initial_args
&& ctl
->args_per_exec
&&
207 ( (state
->cmd_argc
- ctl
->initial_argc
) == ctl
->args_per_exec
))
210 /* We deliberately use an equality test here rather than >= in order
211 * to force a software failure if the code is modified in such a way
212 * that it fails to call this function for every new argument.
214 return state
->cmd_argc
== ctl
->max_arg_count
;
218 /* Add ARG to the end of the list of arguments `cmd_argv' to pass
220 LEN is the length of ARG, including the terminating null.
221 If this brings the list up to its maximum size, execute the command. */
224 bc_push_arg (const struct buildcmd_control
*ctl
,
225 struct buildcmd_state
*state
,
226 const char *arg
, size_t len
,
227 const char *prefix
, size_t pfxlen
,
235 if (state
->cmd_argv_chars
+ len
> ctl
->arg_max
)
237 if (initial_args
|| state
->cmd_argc
== ctl
->initial_argc
)
238 error (1, 0, _("can not fit single argument within argument list size limit"));
239 /* option -i (replace_pat) implies -x (exit_if_size_exceeded) */
241 || (ctl
->exit_if_size_exceeded
&&
242 (ctl
->lines_per_exec
|| ctl
->args_per_exec
)))
243 error (1, 0, _("argument list too long"));
244 do_exec (ctl
, state
);
247 if (bc_argc_limit_reached(initial_args
, ctl
, state
))
248 do_exec (ctl
, state
);
251 if (state
->cmd_argc
>= state
->cmd_argv_alloc
)
253 if (!state
->cmd_argv
)
255 state
->cmd_argv_alloc
= 64;
256 state
->cmd_argv
= (char **) xmalloc (sizeof (char *) * state
->cmd_argv_alloc
);
260 state
->cmd_argv_alloc
*= 2;
261 state
->cmd_argv
= (char **) xrealloc (state
->cmd_argv
,
262 sizeof (char *) * state
->cmd_argv_alloc
);
267 state
->cmd_argv
[state
->cmd_argc
++] = NULL
;
270 state
->cmd_argv
[state
->cmd_argc
++] = state
->argbuf
+ state
->cmd_argv_chars
;
273 strcpy (state
->argbuf
+ state
->cmd_argv_chars
, prefix
);
274 state
->cmd_argv_chars
+= pfxlen
;
277 strcpy (state
->argbuf
+ state
->cmd_argv_chars
, arg
);
278 state
->cmd_argv_chars
+= len
;
280 /* If we have now collected enough arguments,
281 * do the exec immediately. This must be
282 * conditional on arg!=NULL, since do_exec()
283 * actually calls bc_push_arg(ctl, state, NULL, 0, false).
285 if (bc_argc_limit_reached(initial_args
, ctl
, state
))
286 do_exec (ctl
, state
);
289 /* If this is an initial argument, set the high-water mark. */
292 state
->cmd_initial_argv_chars
= state
->cmd_argv_chars
;
297 /* Finds the first occurrence of the substring NEEDLE in the string
298 HAYSTACK. Both strings can be multibyte strings. */
301 mbstrstr (const char *haystack
, const char *needle
)
306 size_t hlen
= strlen (haystack
);
307 size_t nlen
= strlen (needle
);
311 memset (&mbstate
, 0, sizeof (mbstate_t));
314 if (memcmp (haystack
, needle
, nlen
) == 0)
315 return (char *) haystack
;
316 step
= mbrlen (haystack
, hlen
, &mbstate
);
325 return strstr (haystack
, needle
);
334 val
= sysconf(_SC_ARG_MAX
);
342 /* either _SC_ARG_MAX was not available or
343 * there is no particular limit.
352 /* The value returned by this function bounds the
353 * value applied as the ceiling for the -s option.
354 * Hence it the system won't tell us what its limit
355 * is, we allow the user to specify more or less
356 * whatever value they like.
362 static int cb_exec_noop(const struct buildcmd_control
*ctl
,
363 struct buildcmd_state
*state
)
373 bc_init_controlinfo(struct buildcmd_control
*ctl
)
375 long arg_max
= bc_get_arg_max();
378 ctl
->exit_if_size_exceeded
= 0;
379 ctl
->arg_max
= arg_max
- 2048; /* a la xargs */
380 /* need to subtract 2 on the following line - for Linux/PPC */
381 ctl
->max_arg_count
= (arg_max
/ sizeof(void*)) - 2;
382 assert(ctl
->max_arg_count
> 0);
384 ctl
->replace_pat
= NULL
;
385 ctl
->initial_argc
= 0;
386 ctl
->exec_callback
= cb_exec_noop
;
387 ctl
->lines_per_exec
= 0;
388 ctl
->args_per_exec
= 0;
392 bc_init_state(const struct buildcmd_control
*ctl
,
393 struct buildcmd_state
*state
,
397 state
->cmd_argv_chars
= 0;
398 state
->cmd_argv
= NULL
;
399 state
->cmd_argv_alloc
= 0;
401 /* XXX: the following memory allocation is inadvisable on systems
402 * with no ARG_MAX, because ctl->arg_max may actually be LONG_MAX.
403 * Also, adding one to that is a bad idea.
405 state
->argbuf
= (char *) xmalloc (ctl
->arg_max
+ 1);
407 state
->cmd_argv_chars
= state
->cmd_initial_argv_chars
= 0;
409 state
->usercontext
= context
;
413 bc_clear_args(const struct buildcmd_control
*ctl
,
414 struct buildcmd_state
*state
)
416 state
->cmd_argc
= ctl
->initial_argc
;
417 state
->cmd_argv_chars
= state
->cmd_initial_argv_chars
;