exec.c@ 2648

Last change on this file since 2648 was 2648, checked in by bird, 12 years ago
Made TRACE2 and TRACE2V safe. Fixed DEBUG bug where va_copy was missing. Introduced sh_strerror.
Property svn:eol-style set to `LF` Property svn:keywords set to `Id`
File size: 27.2 KB

Line
1	/* $NetBSD: exec.c,v 1.37 2003/08/07 09:05:31 agc Exp $ */
2
3	/*-
4	* Copyright (c) 1991, 1993
5	* The Regents of the University of California. All rights reserved.
6	*
7	* This code is derived from software contributed to Berkeley by
8	* Kenneth Almquist.
9	*
10	* Redistribution and use in source and binary forms, with or without
11	* modification, are permitted provided that the following conditions
12	* are met:
13	* 1. Redistributions of source code must retain the above copyright
14	* notice, this list of conditions and the following disclaimer.
15	* 2. Redistributions in binary form must reproduce the above copyright
16	* notice, this list of conditions and the following disclaimer in the
17	* documentation and/or other materials provided with the distribution.
18	* 3. Neither the name of the University nor the names of its contributors
19	* may be used to endorse or promote products derived from this software
20	* without specific prior written permission.
21	*
22	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32	* SUCH DAMAGE.
33	*/
34
35	#if 0
36	#ifndef lint
37	static char sccsid[] = "@(#)exec.c 8.4 (Berkeley) 6/8/95";
38	#else
39	__RCSID("$NetBSD: exec.c,v 1.37 2003/08/07 09:05:31 agc Exp $");
40	#endif /* not lint */
41	#endif
42
43	#include <sys/types.h>
44	#include <errno.h>
45	#include <stdio.h>
46	#include <stdlib.h>
47
48	/*
49	* When commands are first encountered, they are entered in a hash table.
50	* This ensures that a full path search will not have to be done for them
51	* on each invocation.
52	*
53	* We should investigate converting to a linear search, even though that
54	* would make the command name "hash" a misnomer.
55	*/
56
57	#include "shell.h"
58	#include "main.h"
59	#include "nodes.h"
60	#include "parser.h"
61	#include "redir.h"
62	#include "eval.h"
63	#include "exec.h"
64	#include "builtins.h"
65	#include "var.h"
66	#include "options.h"
67	#include "input.h"
68	#include "output.h"
69	#include "syntax.h"
70	#include "memalloc.h"
71	#include "error.h"
72	#include "init.h"
73	#include "mystring.h"
74	#include "show.h"
75	#include "jobs.h"
76	#include "alias.h"
77	#ifdef __INNOTEK_LIBC__
78	#include <InnoTekLIBC/backend.h>
79	#endif
80	#include "shinstance.h"
81
82	//#define CMDTABLESIZE 31 /* should be prime */
83	//#define ARB 1 /* actual size determined at run time */
84	//
85	//
86	//
87	//struct tblentry {
88	// struct tblentry next; / next entry in hash chain */
89	// union param param; /* definition of builtin function */
90	// short cmdtype; /* index identifying command */
91	// char rehash; /* if set, cd done since entry created */
92	// char cmdname[ARB]; /* name of command */
93	//};
94	//
95	//
96	//STATIC struct tblentry *cmdtable[CMDTABLESIZE];
97	//STATIC int builtinloc = -1; /* index in path of %builtin, or -1 */
98	//int exerrno = 0; /* Last exec error */
99
100
101	STATIC void tryexec(shinstance , char , char , char , int, int);
102	STATIC void execinterp(shinstance , char , char *);
103	STATIC void printentry(shinstance , struct tblentry , int);
104	STATIC void clearcmdentry(shinstance *, int);
105	STATIC struct tblentry cmdlookup(shinstance , const char *, int);
106	STATIC void delete_cmd_entry(shinstance *);
107	#ifdef PC_EXE_EXTS
108	STATIC int stat_pc_exec_exts(shinstance , char fullname, struct stat *st, int has_ext);
109	#endif
110
111
112	extern char *const parsekwd[];
113
114	/*
115	* Exec a program. Never returns. If you change this routine, you may
116	* have to change the find_command routine as well.
117	*/
118
119	SH_NORETURN_1 void
120	shellexec(shinstance psh, char argv, char envp, const char path, int idx, int vforked)
121	{
122	char *cmdname;
123	int e;
124	#ifdef PC_EXE_EXTS
125	int has_ext = (int)strlen(argv[0]) - 4;
126	has_ext = has_ext > 0
127	&& argv[0][has_ext] == '.'
128	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
129	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
130	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
131	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
132	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
133	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
134	argv[0] + has_ext + 1)
135	!= NULL;
136	#else
137	const int has_ext = 1;
138	#endif
139	TRACE((psh, "shellexec: argv[0]=%s idx=%d\n", argv[0], idx));
140	if (strchr(argv[0], '/') != NULL) {
141	cmdname = stalloc(psh, strlen(argv[0]) + 5);
142	strcpy(cmdname, argv[0]);
143	tryexec(psh, cmdname, argv, envp, vforked, has_ext);
144	TRACE((psh, "shellexec: cmdname=%s\n", cmdname));
145	stunalloc(psh, cmdname);
146	e = errno;
147	} else {
148	e = ENOENT;
149	while ((cmdname = padvance(psh, &path, argv[0])) != NULL) {
150	if (--idx < 0 && psh->pathopt == NULL) {
151	tryexec(psh, cmdname, argv, envp, vforked, has_ext);
152	if (errno != ENOENT && errno != ENOTDIR)
153	e = errno;
154	}
155	stunalloc(psh, cmdname);
156	}
157	}
158
159	/* Map to POSIX errors */
160	switch (e) {
161	case EACCES:
162	psh->exerrno = 126;
163	break;
164	case ENOENT:
165	psh->exerrno = 127;
166	break;
167	default:
168	psh->exerrno = 2;
169	break;
170	}
171	TRACE((psh, "shellexec failed for '%s', errno %d, vforked %d, suppressint %d\n",
172	argv[0], e, vforked, psh->suppressint ));
173	exerror(psh, EXEXEC, "%s: %s", argv[0], errmsg(psh, e, E_EXEC));
174	/* NOTREACHED */
175	}
176
177
178	STATIC void
179	tryexec(shinstance psh, char cmd, char argv, char envp, int vforked, int has_ext)
180	{
181	int e;
182	#ifdef EXEC_HASH_BANG_SCRIPT
183	char *p;
184	#endif
185	#ifdef PC_EXE_EXTS
186	/* exploit the effect of stat_pc_exec_exts which adds the
187	* correct extentions to the file.
188	*/
189	struct stat st;
190	if (!has_ext)
191	stat_pc_exec_exts(psh, cmd, &st, 0);
192	#endif
193	#if defined(__INNOTEK_LIBC__) && defined(EXEC_HASH_BANG_SCRIPT)
194	__libc_Back_gfProcessHandleHashBangScripts = 0;
195	#endif
196
197	#ifdef SYSV
198	do {
199	sh_execve(psh, cmd, argv, envp);
200	} while (errno == EINTR);
201	#else
202	sh_execve(psh, cmd, (const char * const)argv, (const char const*)envp);
203	#endif
204	e = errno;
205	if (e == ENOEXEC) {
206	if (vforked) {
207	/* We are currently vfork(2)ed, so raise an
208	* exception, and evalcommand will try again
209	* with a normal fork(2).
210	*/
211	exraise(psh, EXSHELLPROC);
212	}
213	initshellproc(psh);
214	setinputfile(psh, cmd, 0);
215	psh->commandname = psh->arg0 = savestr(psh, argv[0]);
216	#ifdef EXEC_HASH_BANG_SCRIPT
217	pgetc(psh); pungetc(psh); /* fill up input buffer */
218	p = psh->parsenextc;
219	if (psh->parsenleft > 2 && p[0] == '#' && p[1] == '!') {
220	argv[0] = cmd;
221	execinterp(psh, argv, envp);
222	}
223	#endif
224	setparam(psh, argv + 1);
225	exraise(psh, EXSHELLPROC);
226	}
227	errno = e;
228	}
229
230
231	#ifdef EXEC_HASH_BANG_SCRIPT
232	/*
233	* Execute an interpreter introduced by "#!", for systems where this
234	* feature has not been built into the kernel. If the interpreter is
235	* the shell, return (effectively ignoring the "#!"). If the execution
236	* of the interpreter fails, exit.
237	*
238	* This code peeks inside the input buffer in order to avoid actually
239	* reading any input. It would benefit from a rewrite.
240	*/
241
242	#define NEWARGS 16
243
244	STATIC void
245	execinterp(shinstance psh, char argv, char *envp)
246	{
247	int n;
248	char *inp;
249	char *outp;
250	char c;
251	char *p;
252	char **ap;
253	char *newargs[NEWARGS];
254	int i;
255	char **ap2;
256	char **new;
257
258	n = psh->parsenleft - 2;
259	inp = psh->parsenextc + 2;
260	ap = newargs;
261	for (;;) {
262	while (--n >= 0 && (inp == ' ' \|\| inp == '\t'))
263	inp++;
264	if (n < 0)
265	goto bad;
266	if ((c = *inp++) == '\n')
267	break;
268	if (ap == &newargs[NEWARGS])
269	bad: error(psh, "Bad #! line");
270	STARTSTACKSTR(psh, outp);
271	do {
272	STPUTC(psh, c, outp);
273	} while (--n >= 0 && (c = *inp++) != ' ' && c != '\t' && c != '\n');
274	STPUTC(psh, '\0', outp);
275	n++, inp--;
276	*ap++ = grabstackstr(psh, outp);
277	}
278
279	/* if no args, maybe shell and no exec is needed. */
280	if (ap == newargs + 1) {
281	p = strrchr(newargs[0], '/');
282	if (!p)
283	p = newargs[0];
284	if (equal(p, "kmk_ash") \|\| equal(p, "kmk_sh") \|\| equal(p, "kash") \|\| equal(p, "sh")) {
285	TRACE((psh, "hash bang self\n"));
286	return;
287	}
288	}
289
290	i = (char )ap - (char )newargs; /* size in bytes */
291	if (i == 0)
292	error(psh, "Bad #! line");
293	for (ap2 = argv ; *ap2++ != NULL ; );
294	new = ckmalloc(psh, i + ((char )ap2 - (char )argv));
295	ap = newargs, ap2 = new;
296	while ((i -= sizeof (char **)) >= 0)
297	ap2++ = ap++;
298	ap = argv;
299	while (ap2++ = ap++);
300	TRACE((psh, "hash bang '%s'\n", new[0]));
301	shellexec(psh, new, envp, pathval(psh), 0, 0);
302	/* NOTREACHED */
303	}
304	#endif
305
306
307
308	/*
309	* Do a path search. The variable path (passed by reference) should be
310	* set to the start of the path before the first call; padvance will update
311	* this value as it proceeds. Successive calls to padvance will return
312	* the possible path expansions in sequence. If an option (indicated by
313	* a percent sign) appears in the path entry then the global variable
314	* psh->pathopt will be set to point to it; otherwise psh->pathopt will be set to
315	* NULL.
316	*/
317
318	//const char *pathopt;
319
320	char *
321	padvance(shinstance psh, const char path, const char name)
322	{
323	const char *p;
324	char *q;
325	const char *start;
326	int len;
327
328	if (*path == NULL)
329	return NULL;
330	start = *path;
331	#ifdef PC_PATH_SEP
332	for (p = start ; p && p != ';' && *p != '%' ; p++);
333	#else
334	for (p = start ; p && p != ':' && *p != '%' ; p++);
335	#endif
336	len = (int)(p - start + strlen(name) + 2); /* "2" is for '/' and '\0' */
337	#ifdef PC_EXE_EXTS
338	len += 4; /* "4" is for .exe/.com/.cmd/.bat/.btm */
339	#endif
340	while (stackblocksize(psh) < len)
341	growstackblock(psh);
342	q = stackblock(psh);
343	if (p != start) {
344	memcpy(q, start, p - start);
345	q += p - start;
346	*q++ = '/';
347	}
348	strcpy(q, name);
349	psh->pathopt = NULL;
350	if (*p == '%') {
351	psh->pathopt = ++p;
352	#ifdef PC_PATH_SEP
353	while (p && p != ';') p++;
354	#else
355	while (p && p != ':') p++;
356	#endif
357	}
358	#ifdef PC_PATH_SEP
359	if (*p == ';')
360	#else
361	if (*p == ':')
362	#endif
363	*path = p + 1;
364	else
365	*path = NULL;
366	return stalloc(psh, len);
367	}
368
369
370	#ifdef PC_EXE_EXTS
371	STATIC int stat_pc_exec_exts(shinstance psh, char fullname, struct stat *st, int has_ext)
372	{
373	/* skip the SYSV crap */
374	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
375	return 0;
376	if (!has_ext && errno == ENOENT)
377	{
378	char *psz = strchr(fullname, '\0');
379	memcpy(psz, ".exe", 5);
380	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
381	return 0;
382	if (errno != ENOENT && errno != ENOTDIR)
383	return -1;
384
385	memcpy(psz, ".cmd", 5);
386	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
387	return 0;
388	if (errno != ENOENT && errno != ENOTDIR)
389	return -1;
390
391	memcpy(psz, ".bat", 5);
392	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
393	return 0;
394	if (errno != ENOENT && errno != ENOTDIR)
395	return -1;
396
397	memcpy(psz, ".com", 5);
398	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
399	return 0;
400	if (errno != ENOENT && errno != ENOTDIR)
401	return -1;
402
403	memcpy(psz, ".btm", 5);
404	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
405	return 0;
406	*psz = '\0';
407	}
408	return -1;
409	}
410	#endif /* PC_EXE_EXTS */
411
412
413
414	/* Command hashing code */
415
416
417	int
418	hashcmd(shinstance psh, int argc, char *argv)
419	{
420	struct tblentry **pp;
421	struct tblentry *cmdp;
422	int c;
423	int verbose;
424	struct cmdentry entry;
425	char *name;
426
427	verbose = 0;
428	while ((c = nextopt(psh, "rv")) != '\0') {
429	if (c == 'r') {
430	clearcmdentry(psh, 0);
431	} else if (c == 'v') {
432	verbose++;
433	}
434	}
435	if (*psh->argptr == NULL) {
436	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
437	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
438	if (verbose \|\| cmdp->cmdtype == CMDNORMAL)
439	printentry(psh, cmdp, verbose);
440	}
441	}
442	return 0;
443	}
444	while ((name = *psh->argptr) != NULL) {
445	if ((cmdp = cmdlookup(psh, name, 0)) != NULL
446	&& (cmdp->cmdtype == CMDNORMAL
447	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0)))
448	delete_cmd_entry(psh);
449	find_command(psh, name, &entry, DO_ERR, pathval(psh));
450	if (verbose) {
451	if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
452	cmdp = cmdlookup(psh, name, 0);
453	printentry(psh, cmdp, verbose);
454	}
455	output_flushall(psh);
456	}
457	psh->argptr++;
458	}
459	return 0;
460	}
461
462
463	STATIC void
464	printentry(shinstance psh, struct tblentry cmdp, int verbose)
465	{
466	int idx;
467	const char *path;
468	char *name;
469
470	switch (cmdp->cmdtype) {
471	case CMDNORMAL:
472	idx = cmdp->param.index;
473	path = pathval(psh);
474	do {
475	name = padvance(psh, &path, cmdp->cmdname);
476	stunalloc(psh, name);
477	} while (--idx >= 0);
478	out1str(psh, name);
479	break;
480	case CMDSPLBLTIN:
481	out1fmt(psh, "special builtin %s", cmdp->cmdname);
482	break;
483	case CMDBUILTIN:
484	out1fmt(psh, "builtin %s", cmdp->cmdname);
485	break;
486	case CMDFUNCTION:
487	out1fmt(psh, "function %s", cmdp->cmdname);
488	if (verbose) {
489	struct procstat ps;
490	INTOFF;
491	commandtext(psh, &ps, cmdp->param.func);
492	INTON;
493	out1str(psh, "() { ");
494	out1str(psh, ps.cmd);
495	out1str(psh, "; }");
496	}
497	break;
498	default:
499	error(psh, "internal error: %s cmdtype %d", cmdp->cmdname, cmdp->cmdtype);
500	}
501	if (cmdp->rehash)
502	out1c(psh, '*');
503	out1c(psh, '\n');
504	}
505
506
507
508	/*
509	* Resolve a command name. If you change this routine, you may have to
510	* change the shellexec routine as well.
511	*/
512
513	void
514	find_command(shinstance psh, char name, struct cmdentry entry, int act, const char path)
515	{
516	struct tblentry *cmdp, loc_cmd;
517	int idx;
518	int prev;
519	char *fullname;
520	struct stat statb;
521	int e;
522	int (bltin)(shinstance,int,char **);
523
524	#ifdef PC_EXE_EXTS
525	int has_ext = (int)(strlen(name) - 4);
526	has_ext = has_ext > 0
527	&& name[has_ext] == '.'
528	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
529	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
530	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
531	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
532	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
533	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
534	name + has_ext + 1)
535	!= NULL;
536	#endif
537
538	/* If name contains a slash, don't use PATH or hash table */
539	if (strchr(name, '/') != NULL) {
540	if (act & DO_ABS) {
541	while (shfile_stat(&psh->fdtab, name, &statb) < 0) {
542	#ifdef SYSV
543	if (errno == EINTR)
544	continue;
545	#endif
546	if (errno != ENOENT && errno != ENOTDIR)
547	e = errno;
548	entry->cmdtype = CMDUNKNOWN;
549	entry->u.index = -1;
550	return;
551	}
552	entry->cmdtype = CMDNORMAL;
553	entry->u.index = -1;
554	return;
555	}
556	entry->cmdtype = CMDNORMAL;
557	entry->u.index = 0;
558	return;
559	}
560
561	if (path != pathval(psh))
562	act \|= DO_ALTPATH;
563
564	if (act & DO_ALTPATH && strstr(path, "%builtin") != NULL)
565	act \|= DO_ALTBLTIN;
566
567	/* If name is in the table, check answer will be ok */
568	if ((cmdp = cmdlookup(psh, name, 0)) != NULL) {
569	do {
570	switch (cmdp->cmdtype) {
571	case CMDNORMAL:
572	if (act & DO_ALTPATH) {
573	cmdp = NULL;
574	continue;
575	}
576	break;
577	case CMDFUNCTION:
578	if (act & DO_NOFUNC) {
579	cmdp = NULL;
580	continue;
581	}
582	break;
583	case CMDBUILTIN:
584	if ((act & DO_ALTBLTIN) \|\| psh->builtinloc >= 0) {
585	cmdp = NULL;
586	continue;
587	}
588	break;
589	}
590	/* if not invalidated by cd, we're done */
591	if (cmdp->rehash == 0)
592	goto success;
593	} while (0);
594	}
595
596	/* If %builtin not in path, check for builtin next */
597	if ((act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : psh->builtinloc < 0) &&
598	(bltin = find_builtin(psh, name)) != 0)
599	goto builtin_success;
600
601	/* We have to search path. */
602	prev = -1; /* where to start */
603	if (cmdp) { /* doing a rehash */
604	if (cmdp->cmdtype == CMDBUILTIN)
605	prev = psh->builtinloc;
606	else
607	prev = cmdp->param.index;
608	}
609
610	e = ENOENT;
611	idx = -1;
612	loop:
613	while ((fullname = padvance(psh, &path, name)) != NULL) {
614	stunalloc(psh, fullname);
615	idx++;
616	if (psh->pathopt) {
617	if (prefix("builtin", psh->pathopt)) {
618	if ((bltin = find_builtin(psh, name)) == 0)
619	goto loop;
620	goto builtin_success;
621	} else if (prefix("func", psh->pathopt)) {
622	/* handled below */
623	} else {
624	/* ignore unimplemented options */
625	goto loop;
626	}
627	}
628	/* if rehash, don't redo absolute path names */
629	if (fullname[0] == '/' && idx <= prev) {
630	if (idx < prev)
631	goto loop;
632	TRACE((psh, "searchexec \"%s\": no change\n", name));
633	goto success;
634	}
635	#ifdef PC_EXE_EXTS
636	while (stat_pc_exec_exts(psh, fullname, &statb, has_ext) < 0) {
637	#else
638	while (shfile_stat(&psh->fdtab, fullname, &statb) < 0) {
639	#endif
640	#ifdef SYSV
641	if (errno == EINTR)
642	continue;
643	#endif
644	if (errno != ENOENT && errno != ENOTDIR)
645	e = errno;
646
647	goto loop;
648	}
649	e = EACCES; /* if we fail, this will be the error */
650	if (!S_ISREG(statb.st_mode))
651	goto loop;
652	if (psh->pathopt) { /* this is a %func directory */
653	if (act & DO_NOFUNC)
654	goto loop;
655	stalloc(psh, strlen(fullname) + 1);
656	readcmdfile(psh, fullname);
657	if ((cmdp = cmdlookup(psh, name, 0)) == NULL \|\|
658	cmdp->cmdtype != CMDFUNCTION)
659	error(psh, "%s not defined in %s", name, fullname);
660	stunalloc(psh, fullname);
661	goto success;
662	}
663	#ifdef notdef
664	/* XXX this code stops root executing stuff, and is buggy
665	if you need a group from the group list. */
666	if (statb.st_uid == sh_geteuid(psh)) {
667	if ((statb.st_mode & 0100) == 0)
668	goto loop;
669	} else if (statb.st_gid == sh_getegid(psh)) {
670	if ((statb.st_mode & 010) == 0)
671	goto loop;
672	} else {
673	if ((statb.st_mode & 01) == 0)
674	goto loop;
675	}
676	#endif
677	TRACE((psh, "searchexec \"%s\" returns \"%s\"\n", name, fullname));
678	INTOFF;
679	if (act & DO_ALTPATH) {
680	stalloc(psh, strlen(fullname) + 1);
681	cmdp = &loc_cmd;
682	} else
683	cmdp = cmdlookup(psh, name, 1);
684	cmdp->cmdtype = CMDNORMAL;
685	cmdp->param.index = idx;
686	INTON;
687	goto success;
688	}
689
690	/* We failed. If there was an entry for this command, delete it */
691	if (cmdp)
692	delete_cmd_entry(psh);
693	if (act & DO_ERR)
694	outfmt(psh->out2, "%s: %s\n", name, errmsg(psh, e, E_EXEC));
695	entry->cmdtype = CMDUNKNOWN;
696	return;
697
698	builtin_success:
699	INTOFF;
700	if (act & DO_ALTPATH)
701	cmdp = &loc_cmd;
702	else
703	cmdp = cmdlookup(psh, name, 1);
704	if (cmdp->cmdtype == CMDFUNCTION)
705	/* DO_NOFUNC must have been set */
706	cmdp = &loc_cmd;
707	cmdp->cmdtype = CMDBUILTIN;
708	cmdp->param.bltin = bltin;
709	INTON;
710	success:
711	cmdp->rehash = 0;
712	entry->cmdtype = cmdp->cmdtype;
713	entry->u = cmdp->param;
714	}
715
716
717
718	/*
719	* Search the table of builtin commands.
720	*/
721
722	int
723	(find_builtin(shinstance psh, char name))(shinstance psh, int, char **)
724	{
725	const struct builtincmd *bp;
726
727	for (bp = builtincmd ; bp->name ; bp++) {
728	if (bp->name == name && equal(bp->name, name))
729	return bp->builtin;
730	}
731	return 0;
732	}
733
734	int
735	(find_splbltin(shinstance psh, char name))(shinstance psh, int, char **)
736	{
737	const struct builtincmd *bp;
738
739	for (bp = splbltincmd ; bp->name ; bp++) {
740	if (bp->name == name && equal(bp->name, name))
741	return bp->builtin;
742	}
743	return 0;
744	}
745
746	/*
747	* At shell startup put special builtins into hash table.
748	* ensures they are executed first (see posix).
749	* We stop functions being added with the same name
750	* (as they are impossible to call)
751	*/
752
753	void
754	hash_special_builtins(shinstance *psh)
755	{
756	const struct builtincmd *bp;
757	struct tblentry *cmdp;
758
759	for (bp = splbltincmd ; bp->name ; bp++) {
760	cmdp = cmdlookup(psh, bp->name, 1);
761	cmdp->cmdtype = CMDSPLBLTIN;
762	cmdp->param.bltin = bp->builtin;
763	}
764	}
765
766
767
768	/*
769	* Called when a cd is done. Marks all commands so the next time they
770	* are executed they will be rehashed.
771	*/
772
773	void
774	hashcd(shinstance *psh)
775	{
776	struct tblentry **pp;
777	struct tblentry *cmdp;
778
779	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
780	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
781	if (cmdp->cmdtype == CMDNORMAL
782	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0))
783	cmdp->rehash = 1;
784	}
785	}
786	}
787
788
789
790	/*
791	* Fix command hash table when PATH changed.
792	* Called before PATH is changed. The argument is the new value of PATH;
793	* pathval(psh) still returns the old value at this point.
794	* Called with interrupts off.
795	*/
796
797	void
798	changepath(shinstance psh, const char newval)
799	{
800	const char old, new;
801	int idx;
802	int firstchange;
803	int bltin;
804
805	old = pathval(psh);
806	new = newval;
807	firstchange = 9999; /* assume no change */
808	idx = 0;
809	bltin = -1;
810	for (;;) {
811	if (old != new) {
812	firstchange = idx;
813	#ifdef PC_PATH_SEP
814	if ((old == '\0' && new == ';')
815	\|\| (old == ';' && new == '\0'))
816	#else
817	if ((old == '\0' && new == ':')
818	\|\| (old == ':' && new == '\0'))
819	#endif
820	firstchange++;
821	old = new; /* ignore subsequent differences */
822	}
823	if (*new == '\0')
824	break;
825	if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
826	bltin = idx;
827	#ifdef PC_PATH_SEP
828	if (*new == ';') {
829	#else
830	if (*new == ':') {
831	#endif
832	idx++;
833	}
834	new++, old++;
835	}
836	if (psh->builtinloc < 0 && bltin >= 0)
837	psh->builtinloc = bltin; /* zap builtins */
838	if (psh->builtinloc >= 0 && bltin < 0)
839	firstchange = 0;
840	clearcmdentry(psh, firstchange);
841	psh->builtinloc = bltin;
842	}
843
844
845	/*
846	* Clear out command entries. The argument specifies the first entry in
847	* PATH which has changed.
848	*/
849
850	STATIC void
851	clearcmdentry(shinstance *psh, int firstchange)
852	{
853	struct tblentry **tblp;
854	struct tblentry **pp;
855	struct tblentry *cmdp;
856
857	INTOFF;
858	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
859	pp = tblp;
860	while ((cmdp = *pp) != NULL) {
861	if ((cmdp->cmdtype == CMDNORMAL &&
862	cmdp->param.index >= firstchange)
863	\|\| (cmdp->cmdtype == CMDBUILTIN &&
864	psh->builtinloc >= firstchange)) {
865	*pp = cmdp->next;
866	ckfree(psh, cmdp);
867	} else {
868	pp = &cmdp->next;
869	}
870	}
871	}
872	INTON;
873	}
874
875
876	/*
877	* Delete all functions.
878	*/
879
880	#ifdef mkinit
881	MKINIT void deletefuncs(struct shinstance *);
882	MKINIT void hash_special_builtins(struct shinstance *);
883
884	INIT {
885	hash_special_builtins(psh);
886	}
887
888	SHELLPROC {
889	deletefuncs(psh);
890	}
891	#endif
892
893	void
894	deletefuncs(shinstance *psh)
895	{
896	struct tblentry **tblp;
897	struct tblentry **pp;
898	struct tblentry *cmdp;
899
900	INTOFF;
901	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
902	pp = tblp;
903	while ((cmdp = *pp) != NULL) {
904	if (cmdp->cmdtype == CMDFUNCTION) {
905	*pp = cmdp->next;
906	freefunc(psh, cmdp->param.func);
907	ckfree(psh, cmdp);
908	} else {
909	pp = &cmdp->next;
910	}
911	}
912	}
913	INTON;
914	}
915
916
917
918	/*
919	* Locate a command in the command hash table. If "add" is nonzero,
920	* add the command to the table if it is not already present. The
921	* variable "lastcmdentry" is set to point to the address of the link
922	* pointing to the entry, so that delete_cmd_entry can delete the
923	* entry.
924	*/
925
926	struct tblentry **lastcmdentry;
927
928
929	STATIC struct tblentry *
930	cmdlookup(shinstance psh, const char name, int add)
931	{
932	int hashval;
933	const char *p;
934	struct tblentry *cmdp;
935	struct tblentry **pp;
936
937	p = name;
938	hashval = *p << 4;
939	while (*p)
940	hashval += *p++;
941	hashval &= 0x7FFF;
942	pp = &psh->cmdtable[hashval % CMDTABLESIZE];
943	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
944	if (equal(cmdp->cmdname, name))
945	break;
946	pp = &cmdp->next;
947	}
948	if (add && cmdp == NULL) {
949	INTOFF;
950	cmdp = *pp = ckmalloc(psh, sizeof (struct tblentry) - ARB
951	+ strlen(name) + 1);
952	cmdp->next = NULL;
953	cmdp->cmdtype = CMDUNKNOWN;
954	cmdp->rehash = 0;
955	strcpy(cmdp->cmdname, name);
956	INTON;
957	}
958	lastcmdentry = pp;
959	return cmdp;
960	}
961
962	/*
963	* Delete the command entry returned on the last lookup.
964	*/
965
966	STATIC void
967	delete_cmd_entry(shinstance *psh)
968	{
969	struct tblentry *cmdp;
970
971	INTOFF;
972	cmdp = *lastcmdentry;
973	*lastcmdentry = cmdp->next;
974	ckfree(psh, cmdp);
975	INTON;
976	}
977
978
979
980	#ifdef notdef
981	void
982	getcmdentry(shinstance psh, char name, struct cmdentry *entry)
983	{
984	struct tblentry *cmdp = cmdlookup(psh, name, 0);
985
986	if (cmdp) {
987	entry->u = cmdp->param;
988	entry->cmdtype = cmdp->cmdtype;
989	} else {
990	entry->cmdtype = CMDUNKNOWN;
991	entry->u.index = 0;
992	}
993	}
994	#endif
995
996
997	/*
998	* Add a new command entry, replacing any existing command entry for
999	* the same name - except special builtins.
1000	*/
1001
1002	STATIC void
1003	addcmdentry(shinstance psh, char name, struct cmdentry *entry)
1004	{
1005	struct tblentry *cmdp;
1006
1007	INTOFF;
1008	cmdp = cmdlookup(psh, name, 1);
1009	if (cmdp->cmdtype != CMDSPLBLTIN) {
1010	if (cmdp->cmdtype == CMDFUNCTION) {
1011	freefunc(psh, cmdp->param.func);
1012	}
1013	cmdp->cmdtype = entry->cmdtype;
1014	cmdp->param = entry->u;
1015	}
1016	INTON;
1017	}
1018
1019
1020	/*
1021	* Define a shell function.
1022	*/
1023
1024	void
1025	defun(shinstance psh, char name, union node *func)
1026	{
1027	struct cmdentry entry;
1028
1029	INTOFF;
1030	entry.cmdtype = CMDFUNCTION;
1031	entry.u.func = copyfunc(psh, func);
1032	addcmdentry(psh, name, &entry);
1033	INTON;
1034	}
1035
1036
1037	/*
1038	* Delete a function if it exists.
1039	*/
1040
1041	int
1042	unsetfunc(shinstance psh, char name)
1043	{
1044	struct tblentry *cmdp;
1045
1046	if ((cmdp = cmdlookup(psh, name, 0)) != NULL &&
1047	cmdp->cmdtype == CMDFUNCTION) {
1048	freefunc(psh, cmdp->param.func);
1049	delete_cmd_entry(psh);
1050	return (0);
1051	}
1052	return (1);
1053	}
1054
1055	/*
1056	* Locate and print what a word is...
1057	* also used for 'command -[v\|V]'
1058	*/
1059
1060	int
1061	typecmd(shinstance psh, int argc, char *argv)
1062	{
1063	struct cmdentry entry;
1064	struct tblentry *cmdp;
1065	char * const *pp;
1066	struct alias *ap;
1067	int err = 0;
1068	char *arg;
1069	int c;
1070	int V_flag = 0;
1071	int v_flag = 0;
1072	int p_flag = 0;
1073
1074	while ((c = nextopt(psh, "vVp")) != 0) {
1075	switch (c) {
1076	case 'v': v_flag = 1; break;
1077	case 'V': V_flag = 1; break;
1078	case 'p': p_flag = 1; break;
1079	}
1080	}
1081
1082	if (p_flag && (v_flag \|\| V_flag))
1083	error(psh, "cannot specify -p with -v or -V");
1084
1085	while ((arg = *psh->argptr++)) {
1086	if (!v_flag)
1087	out1str(psh, arg);
1088	/* First look at the keywords */
1089	for (pp = parsekwd; *pp; pp++)
1090	if (*pp == arg && equal(*pp, arg))
1091	break;
1092
1093	if (*pp) {
1094	if (v_flag)
1095	err = 1;
1096	else
1097	out1str(psh, " is a shell keyword\n");
1098	continue;
1099	}
1100
1101	/* Then look at the aliases */
1102	if ((ap = lookupalias(psh, arg, 1)) != NULL) {
1103	if (!v_flag)
1104	out1fmt(psh, " is an alias for \n");
1105	out1fmt(psh, "%s\n", ap->val);
1106	continue;
1107	}
1108
1109	/* Then check if it is a tracked alias */
1110	if ((cmdp = cmdlookup(psh, arg, 0)) != NULL) {
1111	entry.cmdtype = cmdp->cmdtype;
1112	entry.u = cmdp->param;
1113	} else {
1114	/* Finally use brute force */
1115	find_command(psh, arg, &entry, DO_ABS, pathval(psh));
1116	}
1117
1118	switch (entry.cmdtype) {
1119	case CMDNORMAL: {
1120	if (strchr(arg, '/') == NULL) {
1121	const char *path = pathval(psh);
1122	char *name;
1123	int j = entry.u.index;
1124	do {
1125	name = padvance(psh, &path, arg);
1126	stunalloc(psh, name);
1127	} while (--j >= 0);
1128	if (!v_flag)
1129	out1fmt(psh, " is%s ",
1130	cmdp ? " a tracked alias for" : "");
1131	out1fmt(psh, "%s\n", name);
1132	} else {
1133	if (shfile_access(&psh->fdtab, arg, X_OK) == 0) {
1134	if (!v_flag)
1135	out1fmt(psh, " is ");
1136	out1fmt(psh, "%s\n", arg);
1137	} else {
1138	if (!v_flag)
1139	out1fmt(psh, ": %s\n",
1140	sh_strerror(psh, errno));
1141	else
1142	err = 126;
1143	}
1144	}
1145	break;
1146	}
1147	case CMDFUNCTION:
1148	if (!v_flag)
1149	out1str(psh, " is a shell function\n");
1150	else
1151	out1fmt(psh, "%s\n", arg);
1152	break;
1153
1154	case CMDBUILTIN:
1155	if (!v_flag)
1156	out1str(psh, " is a shell builtin\n");
1157	else
1158	out1fmt(psh, "%s\n", arg);
1159	break;
1160
1161	case CMDSPLBLTIN:
1162	if (!v_flag)
1163	out1str(psh, " is a special shell builtin\n");
1164	else
1165	out1fmt(psh, "%s\n", arg);
1166	break;
1167
1168	default:
1169	if (!v_flag)
1170	out1str(psh, ": not found\n");
1171	err = 127;
1172	break;
1173	}
1174	}
1175	return err;
1176	}

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source: kBuild/trunk/src/kash/exec.c@ 2648

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