exec.c@ 1203

Last change on this file since 1203 was 1203, checked in by bird, 17 years ago
converted a few more files.
Property svn:eol-style set to `native`
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	#ifdef HAVE_SYS_CDEFS_H
36	#include <sys/cdefs.h>
37	#endif
38	#ifndef lint
39	#if 0
40	static char sccsid[] = "@(#)exec.c 8.4 (Berkeley) 6/8/95";
41	#else
42	__RCSID("$NetBSD: exec.c,v 1.37 2003/08/07 09:05:31 agc Exp $");
43	#endif
44	#endif /* not lint */
45
46	#include <sys/types.h>
47	#include <sys/stat.h>
48	#include <sys/wait.h>
49	#include <unistd.h>
50	#include <fcntl.h>
51	#include <errno.h>
52	#include <stdio.h>
53	#include <stdlib.h>
54
55	/*
56	* When commands are first encountered, they are entered in a hash table.
57	* This ensures that a full path search will not have to be done for them
58	* on each invocation.
59	*
60	* We should investigate converting to a linear search, even though that
61	* would make the command name "hash" a misnomer.
62	*/
63
64	#include "shell.h"
65	#include "main.h"
66	#include "nodes.h"
67	#include "parser.h"
68	#include "redir.h"
69	#include "eval.h"
70	#include "exec.h"
71	#include "builtins.h"
72	#include "var.h"
73	#include "options.h"
74	#include "input.h"
75	#include "output.h"
76	#include "syntax.h"
77	#include "memalloc.h"
78	#include "error.h"
79	#include "init.h"
80	#include "mystring.h"
81	#include "show.h"
82	#include "jobs.h"
83	#include "alias.h"
84	#ifdef __INNOTEK_LIBC__
85	#include <InnoTekLIBC/backend.h>
86	#endif
87
88	#include "shinstance.h"
89
90	//#define CMDTABLESIZE 31 /* should be prime */
91	//#define ARB 1 /* actual size determined at run time */
92	//
93	//
94	//
95	//struct tblentry {
96	// struct tblentry next; / next entry in hash chain */
97	// union param param; /* definition of builtin function */
98	// short cmdtype; /* index identifying command */
99	// char rehash; /* if set, cd done since entry created */
100	// char cmdname[ARB]; /* name of command */
101	//};
102	//
103	//
104	//STATIC struct tblentry *cmdtable[CMDTABLESIZE];
105	//STATIC int builtinloc = -1; /* index in path of %builtin, or -1 */
106	//int exerrno = 0; /* Last exec error */
107
108
109	STATIC void tryexec(shinstance , char , char , char , int, int);
110	STATIC void execinterp(shinstance , char , char *);
111	STATIC void printentry(shinstance , struct tblentry , int);
112	STATIC void clearcmdentry(shinstance *, int);
113	STATIC struct tblentry cmdlookup(shinstance , const char *, int);
114	STATIC void delete_cmd_entry(shinstance *);
115	#ifdef PC_EXE_EXTS
116	STATIC int stat_pc_exec_exts(shinstance , char fullname, struct stat *st, int has_ext);
117	#endif
118
119
120	extern char *const parsekwd[];
121
122	/*
123	* Exec a program. Never returns. If you change this routine, you may
124	* have to change the find_command routine as well.
125	*/
126
127	void
128	shellexec(shinstance psh, char argv, char envp, const char path, int idx, int vforked)
129	{
130	char *cmdname;
131	int e;
132	#ifdef PC_EXE_EXTS
133	int has_ext = (int)strlen(argv[0]) - 4;
134	has_ext = has_ext > 0
135	&& argv[0][has_ext] == '.'
136	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
137	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
138	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
139	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
140	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
141	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
142	argv[0] + has_ext + 1)
143	!= NULL;
144	#else
145	const int has_ext = 1;
146	#endif
147	TRACE((psh, "shellexec: argv[0]=%s idx=%d\n", argv[0], idx));
148	if (strchr(argv[0], '/') != NULL) {
149	cmdname = stalloc(psh, strlen(argv[0]) + 5);
150	strcpy(cmdname, argv[0]);
151	tryexec(psh, cmdname, argv, envp, vforked, has_ext);
152	TRACE((psh, "shellexec: cmdname=%s\n", cmdname));
153	stunalloc(psh, cmdname);
154	e = errno;
155	} else {
156	e = ENOENT;
157	while ((cmdname = padvance(psh, &path, argv[0])) != NULL) {
158	if (--idx < 0 && psh->pathopt == NULL) {
159	tryexec(psh, cmdname, argv, envp, vforked, has_ext);
160	if (errno != ENOENT && errno != ENOTDIR)
161	e = errno;
162	}
163	stunalloc(psh, cmdname);
164	}
165	}
166
167	/* Map to POSIX errors */
168	switch (e) {
169	case EACCES:
170	psh->exerrno = 126;
171	break;
172	case ENOENT:
173	psh->exerrno = 127;
174	break;
175	default:
176	psh->exerrno = 2;
177	break;
178	}
179	TRACE((psh, "shellexec failed for '%s', errno %d, vforked %d, suppressint %d\n",
180	argv[0], e, vforked, psh->suppressint ));
181	exerror(psh, EXEXEC, "%s: %s", argv[0], errmsg(psh, e, E_EXEC));
182	/* NOTREACHED */
183	}
184
185
186	STATIC void
187	tryexec(shinstance psh, char cmd, char argv, char envp, int vforked, int has_ext)
188	{
189	int e;
190	#ifdef EXEC_HASH_BANG_SCRIPT
191	char *p;
192	#endif
193	#ifdef PC_EXE_EXTS
194	/* exploit the effect of stat_pc_exec_exts which adds the
195	* correct extentions to the file.
196	*/
197	struct stat st;
198	if (!has_ext)
199	stat_pc_exec_exts(psh, cmd, &st, 0);
200	#endif
201	#if defined __INNOTEK_LIBC__ && defined EXEC_HASH_BANG_SCRIPT
202	__libc_Back_gfProcessHandleHashBangScripts = 0;
203	#endif
204
205	#ifdef SYSV
206	do {
207	sh_execve(psh, cmd, argv, envp);
208	} while (errno == EINTR);
209	#else
210	sh_execve(psh, cmd, argv, envp);
211	#endif
212	e = errno;
213	if (e == ENOEXEC) {
214	if (vforked) {
215	/* We are currently vfork(2)ed, so raise an
216	* exception, and evalcommand will try again
217	* with a normal fork(2).
218	*/
219	exraise(psh, EXSHELLPROC);
220	}
221	initshellproc(psh);
222	setinputfile(psh, cmd, 0);
223	psh->commandname = psh->arg0 = savestr(argv[0]);
224	#ifdef EXEC_HASH_BANG_SCRIPT
225	pgetc(psh); pungetc(psh); /* fill up input buffer */
226	p = psh->parsenextc;
227	if (psh->parsenleft > 2 && p[0] == '#' && p[1] == '!') {
228	argv[0] = cmd;
229	execinterp(psh, argv, envp);
230	}
231	#endif
232	setparam(psh, argv + 1);
233	exraise(psh, EXSHELLPROC);
234	}
235	errno = e;
236	}
237
238
239	#ifdef EXEC_HASH_BANG_SCRIPT
240	/*
241	* Execute an interpreter introduced by "#!", for systems where this
242	* feature has not been built into the kernel. If the interpreter is
243	* the shell, return (effectively ignoring the "#!"). If the execution
244	* of the interpreter fails, exit.
245	*
246	* This code peeks inside the input buffer in order to avoid actually
247	* reading any input. It would benefit from a rewrite.
248	*/
249
250	#define NEWARGS 5
251
252	STATIC void
253	execinterp(shinstance psh, char argv, char *envp)
254	{
255	int n;
256	char *inp;
257	char *outp;
258	char c;
259	char *p;
260	char **ap;
261	char *newargs[NEWARGS];
262	int i;
263	char **ap2;
264	char **new;
265
266	n = psh->parsenleft - 2;
267	inp = psh->parsenextc + 2;
268	ap = newargs;
269	for (;;) {
270	while (--n >= 0 && (inp == ' ' \|\| inp == '\t'))
271	inp++;
272	if (n < 0)
273	goto bad;
274	if ((c = *inp++) == '\n')
275	break;
276	if (ap == &newargs[NEWARGS])
277	bad: error(psh, "Bad #! line");
278	STARTSTACKSTR(psh, outp);
279	do {
280	STPUTC(psh, c, outp);
281	} while (--n >= 0 && (c = *inp++) != ' ' && c != '\t' && c != '\n');
282	STPUTC(psh, '\0', outp);
283	n++, inp--;
284	*ap++ = grabstackstr(psh, outp);
285	}
286	if (ap == newargs + 1) { /* if no args, maybe no exec is needed */
287	p = newargs[0];
288	for (;;) {
289	if (equal(p, "sh") \|\| equal(p, "ash")) {
290	TRACE((psh, "hash bang self\n"));
291	return;
292	}
293	while (*p != '/') {
294	if (*p == '\0')
295	goto break2;
296	p++;
297	}
298	p++;
299	}
300	break2:;
301	}
302	i = (char )ap - (char )newargs; /* size in bytes */
303	if (i == 0)
304	error(psh, "Bad #! line");
305	for (ap2 = argv ; *ap2++ != NULL ; );
306	new = ckmalloc(i + ((char )ap2 - (char )argv));
307	ap = newargs, ap2 = new;
308	while ((i -= sizeof (char **)) >= 0)
309	ap2++ = ap++;
310	ap = argv;
311	while (ap2++ = ap++);
312	TRACE((psh, "hash bang '%s'\n", new[0]));
313	shellexec(psh, new, envp, pathval(psh), 0, 0);
314	/* NOTREACHED */
315	}
316	#endif
317
318
319
320	/*
321	* Do a path search. The variable path (passed by reference) should be
322	* set to the start of the path before the first call; padvance will update
323	* this value as it proceeds. Successive calls to padvance will return
324	* the possible path expansions in sequence. If an option (indicated by
325	* a percent sign) appears in the path entry then the global variable
326	* psh->pathopt will be set to point to it; otherwise psh->pathopt will be set to
327	* NULL.
328	*/
329
330	//const char *pathopt;
331
332	char *
333	padvance(shinstance psh, const char path, const char name)
334	{
335	const char *p;
336	char *q;
337	const char *start;
338	int len;
339
340	if (*path == NULL)
341	return NULL;
342	start = *path;
343	#ifdef PC_PATH_SEP
344	for (p = start ; p && p != ';' && *p != '%' ; p++);
345	#else
346	for (p = start ; p && p != ':' && *p != '%' ; p++);
347	#endif
348	len = (int)(p - start + strlen(name) + 2); /* "2" is for '/' and '\0' */
349	#ifdef PC_EXE_EXTS
350	len += 4; /* "4" is for .exe/.com/.cmd/.bat/.btm */
351	#endif
352	while (stackblocksize(psh) < len)
353	growstackblock(psh);
354	q = stackblock(psh);
355	if (p != start) {
356	memcpy(q, start, p - start);
357	q += p - start;
358	*q++ = '/';
359	}
360	strcpy(q, name);
361	psh->pathopt = NULL;
362	if (*p == '%') {
363	psh->pathopt = ++p;
364	#ifdef PC_PATH_SEP
365	while (p && p != ';') p++;
366	#else
367	while (p && p != ':') p++;
368	#endif
369	}
370	#ifdef PC_PATH_SEP
371	if (*p == ';')
372	#else
373	if (*p == ':')
374	#endif
375	*path = p + 1;
376	else
377	*path = NULL;
378	return stalloc(psh, len);
379	}
380
381
382	#ifdef PC_EXE_EXTS
383	STATIC int stat_pc_exec_exts(shinstance psh, char fullname, struct stat *st, int has_ext)
384	{
385	/* skip the SYSV crap */
386	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
387	return 0;
388	if (!has_ext && errno == ENOENT)
389	{
390	char *psz = strchr(fullname, '\0');
391	memcpy(psz, ".exe", 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, ".cmd", 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, ".bat", 5);
404	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
405	return 0;
406	if (errno != ENOENT && errno != ENOTDIR)
407	return -1;
408
409	memcpy(psz, ".com", 5);
410	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
411	return 0;
412	if (errno != ENOENT && errno != ENOTDIR)
413	return -1;
414
415	memcpy(psz, ".btm", 5);
416	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
417	return 0;
418	*psz = '\0';
419	}
420	return -1;
421	}
422	#endif /* PC_EXE_EXTS */
423
424
425
426	/* Command hashing code */
427
428
429	int
430	hashcmd(shinstance psh, int argc, char *argv)
431	{
432	struct tblentry **pp;
433	struct tblentry *cmdp;
434	int c;
435	int verbose;
436	struct cmdentry entry;
437	char *name;
438
439	verbose = 0;
440	while ((c = nextopt(psh, "rv")) != '\0') {
441	if (c == 'r') {
442	clearcmdentry(psh, 0);
443	} else if (c == 'v') {
444	verbose++;
445	}
446	}
447	if (*psh->argptr == NULL) {
448	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
449	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
450	if (verbose \|\| cmdp->cmdtype == CMDNORMAL)
451	printentry(psh, cmdp, verbose);
452	}
453	}
454	return 0;
455	}
456	while ((name = *psh->argptr) != NULL) {
457	if ((cmdp = cmdlookup(psh, name, 0)) != NULL
458	&& (cmdp->cmdtype == CMDNORMAL
459	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0)))
460	delete_cmd_entry(psh);
461	find_command(psh, name, &entry, DO_ERR, pathval(psh));
462	if (verbose) {
463	if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
464	cmdp = cmdlookup(psh, name, 0);
465	printentry(psh, cmdp, verbose);
466	}
467	output_flushall(psh);
468	}
469	psh->argptr++;
470	}
471	return 0;
472	}
473
474
475	STATIC void
476	printentry(shinstance psh, struct tblentry cmdp, int verbose)
477	{
478	int idx;
479	const char *path;
480	char *name;
481
482	switch (cmdp->cmdtype) {
483	case CMDNORMAL:
484	idx = cmdp->param.index;
485	path = pathval(psh);
486	do {
487	name = padvance(psh, &path, cmdp->cmdname);
488	stunalloc(psh, name);
489	} while (--idx >= 0);
490	out1str(psh, name);
491	break;
492	case CMDSPLBLTIN:
493	out1fmt(psh, "special builtin %s", cmdp->cmdname);
494	break;
495	case CMDBUILTIN:
496	out1fmt(psh, "builtin %s", cmdp->cmdname);
497	break;
498	case CMDFUNCTION:
499	out1fmt(psh, "function %s", cmdp->cmdname);
500	if (verbose) {
501	struct procstat ps;
502	INTOFF;
503	commandtext(psh, &ps, cmdp->param.func);
504	INTON;
505	out1str(psh, "() { ");
506	out1str(psh, ps.cmd);
507	out1str(psh, "; }");
508	}
509	break;
510	default:
511	error(psh, "internal error: %s cmdtype %d", cmdp->cmdname, cmdp->cmdtype);
512	}
513	if (cmdp->rehash)
514	out1c(psh, '*');
515	out1c(psh, '\n');
516	}
517
518
519
520	/*
521	* Resolve a command name. If you change this routine, you may have to
522	* change the shellexec routine as well.
523	*/
524
525	void
526	find_command(shinstance psh, char name, struct cmdentry entry, int act, const char path)
527	{
528	struct tblentry *cmdp, loc_cmd;
529	int idx;
530	int prev;
531	char *fullname;
532	struct stat statb;
533	int e;
534	int (bltin)(shinstance,int,char **);
535
536	#ifdef PC_EXE_EXTS
537	int has_ext = (int)(strlen(name) - 4);
538	has_ext = has_ext > 0
539	&& name[has_ext] == '.'
540	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
541	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
542	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
543	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
544	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
545	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
546	name + has_ext + 1)
547	!= NULL;
548	#endif
549
550	/* If name contains a slash, don't use PATH or hash table */
551	if (strchr(name, '/') != NULL) {
552	if (act & DO_ABS) {
553	while (shfile_stat(&psh->fdtab, name, &statb) < 0) {
554	#ifdef SYSV
555	if (errno == EINTR)
556	continue;
557	#endif
558	if (errno != ENOENT && errno != ENOTDIR)
559	e = errno;
560	entry->cmdtype = CMDUNKNOWN;
561	entry->u.index = -1;
562	return;
563	}
564	entry->cmdtype = CMDNORMAL;
565	entry->u.index = -1;
566	return;
567	}
568	entry->cmdtype = CMDNORMAL;
569	entry->u.index = 0;
570	return;
571	}
572
573	if (path != pathval(psh))
574	act \|= DO_ALTPATH;
575
576	if (act & DO_ALTPATH && strstr(path, "%builtin") != NULL)
577	act \|= DO_ALTBLTIN;
578
579	/* If name is in the table, check answer will be ok */
580	if ((cmdp = cmdlookup(psh, name, 0)) != NULL) {
581	do {
582	switch (cmdp->cmdtype) {
583	case CMDNORMAL:
584	if (act & DO_ALTPATH) {
585	cmdp = NULL;
586	continue;
587	}
588	break;
589	case CMDFUNCTION:
590	if (act & DO_NOFUNC) {
591	cmdp = NULL;
592	continue;
593	}
594	break;
595	case CMDBUILTIN:
596	if ((act & DO_ALTBLTIN) \|\| psh->builtinloc >= 0) {
597	cmdp = NULL;
598	continue;
599	}
600	break;
601	}
602	/* if not invalidated by cd, we're done */
603	if (cmdp->rehash == 0)
604	goto success;
605	} while (0);
606	}
607
608	/* If %builtin not in path, check for builtin next */
609	if ((act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : psh->builtinloc < 0) &&
610	(bltin = find_builtin(psh, name)) != 0)
611	goto builtin_success;
612
613	/* We have to search path. */
614	prev = -1; /* where to start */
615	if (cmdp) { /* doing a rehash */
616	if (cmdp->cmdtype == CMDBUILTIN)
617	prev = psh->builtinloc;
618	else
619	prev = cmdp->param.index;
620	}
621
622	e = ENOENT;
623	idx = -1;
624	loop:
625	while ((fullname = padvance(psh, &path, name)) != NULL) {
626	stunalloc(psh, fullname);
627	idx++;
628	if (psh->pathopt) {
629	if (prefix("builtin", psh->pathopt)) {
630	if ((bltin = find_builtin(psh, name)) == 0)
631	goto loop;
632	goto builtin_success;
633	} else if (prefix("func", psh->pathopt)) {
634	/* handled below */
635	} else {
636	/* ignore unimplemented options */
637	goto loop;
638	}
639	}
640	/* if rehash, don't redo absolute path names */
641	if (fullname[0] == '/' && idx <= prev) {
642	if (idx < prev)
643	goto loop;
644	TRACE((psh, "searchexec \"%s\": no change\n", name));
645	goto success;
646	}
647	#ifdef PC_EXE_EXTS
648	while (stat_pc_exec_exts(psh, fullname, &statb, has_ext) < 0) {
649	#else
650	while (shfile_stat(&psh->fdtab, fullname, &statb) < 0) {
651	#endif
652	#ifdef SYSV
653	if (errno == EINTR)
654	continue;
655	#endif
656	if (errno != ENOENT && errno != ENOTDIR)
657	e = errno;
658
659	goto loop;
660	}
661	e = EACCES; /* if we fail, this will be the error */
662	if (!S_ISREG(statb.st_mode))
663	goto loop;
664	if (psh->pathopt) { /* this is a %func directory */
665	if (act & DO_NOFUNC)
666	goto loop;
667	stalloc(psh, strlen(fullname) + 1);
668	readcmdfile(psh, fullname);
669	if ((cmdp = cmdlookup(psh, name, 0)) == NULL \|\|
670	cmdp->cmdtype != CMDFUNCTION)
671	error(psh, "%s not defined in %s", name, fullname);
672	stunalloc(psh, fullname);
673	goto success;
674	}
675	#ifdef notdef
676	/* XXX this code stops root executing stuff, and is buggy
677	if you need a group from the group list. */
678	if (statb.st_uid == geteuid()) {
679	if ((statb.st_mode & 0100) == 0)
680	goto loop;
681	} else if (statb.st_gid == getegid()) {
682	if ((statb.st_mode & 010) == 0)
683	goto loop;
684	} else {
685	if ((statb.st_mode & 01) == 0)
686	goto loop;
687	}
688	#endif
689	TRACE((psh, "searchexec \"%s\" returns \"%s\"\n", name, fullname));
690	INTOFF;
691	if (act & DO_ALTPATH) {
692	stalloc(psh, strlen(fullname) + 1);
693	cmdp = &loc_cmd;
694	} else
695	cmdp = cmdlookup(psh, name, 1);
696	cmdp->cmdtype = CMDNORMAL;
697	cmdp->param.index = idx;
698	INTON;
699	goto success;
700	}
701
702	/* We failed. If there was an entry for this command, delete it */
703	if (cmdp)
704	delete_cmd_entry(psh);
705	if (act & DO_ERR)
706	outfmt(psh->out2, "%s: %s\n", name, errmsg(psh, e, E_EXEC));
707	entry->cmdtype = CMDUNKNOWN;
708	return;
709
710	builtin_success:
711	INTOFF;
712	if (act & DO_ALTPATH)
713	cmdp = &loc_cmd;
714	else
715	cmdp = cmdlookup(psh, name, 1);
716	if (cmdp->cmdtype == CMDFUNCTION)
717	/* DO_NOFUNC must have been set */
718	cmdp = &loc_cmd;
719	cmdp->cmdtype = CMDBUILTIN;
720	cmdp->param.bltin = bltin;
721	INTON;
722	success:
723	cmdp->rehash = 0;
724	entry->cmdtype = cmdp->cmdtype;
725	entry->u = cmdp->param;
726	}
727
728
729
730	/*
731	* Search the table of builtin commands.
732	*/
733
734	int
735	(find_builtin(shinstance psh, char name))(shinstance psh, int, char **)
736	{
737	const struct builtincmd *bp;
738
739	for (bp = builtincmd ; bp->name ; bp++) {
740	if (bp->name == name && equal(bp->name, name))
741	return bp->builtin;
742	}
743	return 0;
744	}
745
746	int
747	(find_splbltin(shinstance psh, char name))(shinstance psh, int, char **)
748	{
749	const struct builtincmd *bp;
750
751	for (bp = splbltincmd ; bp->name ; bp++) {
752	if (bp->name == name && equal(bp->name, name))
753	return bp->builtin;
754	}
755	return 0;
756	}
757
758	/*
759	* At shell startup put special builtins into hash table.
760	* ensures they are executed first (see posix).
761	* We stop functions being added with the same name
762	* (as they are impossible to call)
763	*/
764
765	void
766	hash_special_builtins(shinstance *psh)
767	{
768	const struct builtincmd *bp;
769	struct tblentry *cmdp;
770
771	for (bp = splbltincmd ; bp->name ; bp++) {
772	cmdp = cmdlookup(psh, bp->name, 1);
773	cmdp->cmdtype = CMDSPLBLTIN;
774	cmdp->param.bltin = bp->builtin;
775	}
776	}
777
778
779
780	/*
781	* Called when a cd is done. Marks all commands so the next time they
782	* are executed they will be rehashed.
783	*/
784
785	void
786	hashcd(shinstance *psh)
787	{
788	struct tblentry **pp;
789	struct tblentry *cmdp;
790
791	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
792	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
793	if (cmdp->cmdtype == CMDNORMAL
794	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0))
795	cmdp->rehash = 1;
796	}
797	}
798	}
799
800
801
802	/*
803	* Fix command hash table when PATH changed.
804	* Called before PATH is changed. The argument is the new value of PATH;
805	* pathval(psh) still returns the old value at this point.
806	* Called with interrupts off.
807	*/
808
809	void
810	changepath(shinstance psh, const char newval)
811	{
812	const char old, new;
813	int idx;
814	int firstchange;
815	int bltin;
816
817	old = pathval(psh);
818	new = newval;
819	firstchange = 9999; /* assume no change */
820	idx = 0;
821	bltin = -1;
822	for (;;) {
823	if (old != new) {
824	firstchange = idx;
825	#ifdef PC_PATH_SEP
826	if ((old == '\0' && new == ';')
827	\|\| (old == ';' && new == '\0'))
828	#else
829	if ((old == '\0' && new == ':')
830	\|\| (old == ':' && new == '\0'))
831	#endif
832	firstchange++;
833	old = new; /* ignore subsequent differences */
834	}
835	if (*new == '\0')
836	break;
837	if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
838	bltin = idx;
839	#ifdef PC_PATH_SEP
840	if (*new == ';') {
841	#else
842	if (*new == ':') {
843	#endif
844	idx++;
845	}
846	new++, old++;
847	}
848	if (psh->builtinloc < 0 && bltin >= 0)
849	psh->builtinloc = bltin; /* zap builtins */
850	if (psh->builtinloc >= 0 && bltin < 0)
851	firstchange = 0;
852	clearcmdentry(psh, firstchange);
853	psh->builtinloc = bltin;
854	}
855
856
857	/*
858	* Clear out command entries. The argument specifies the first entry in
859	* PATH which has changed.
860	*/
861
862	STATIC void
863	clearcmdentry(shinstance *psh, int firstchange)
864	{
865	struct tblentry **tblp;
866	struct tblentry **pp;
867	struct tblentry *cmdp;
868
869	INTOFF;
870	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
871	pp = tblp;
872	while ((cmdp = *pp) != NULL) {
873	if ((cmdp->cmdtype == CMDNORMAL &&
874	cmdp->param.index >= firstchange)
875	\|\| (cmdp->cmdtype == CMDBUILTIN &&
876	psh->builtinloc >= firstchange)) {
877	*pp = cmdp->next;
878	ckfree(cmdp);
879	} else {
880	pp = &cmdp->next;
881	}
882	}
883	}
884	INTON;
885	}
886
887
888	/*
889	* Delete all functions.
890	*/
891
892	#ifdef mkinit
893	MKINIT void deletefuncs(struct shinstance *);
894	MKINIT void hash_special_builtins(struct shinstance *);
895
896	INIT {
897	hash_special_builtins(psh);
898	}
899
900	SHELLPROC {
901	deletefuncs(psh);
902	}
903	#endif
904
905	void
906	deletefuncs(shinstance *psh)
907	{
908	struct tblentry **tblp;
909	struct tblentry **pp;
910	struct tblentry *cmdp;
911
912	INTOFF;
913	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
914	pp = tblp;
915	while ((cmdp = *pp) != NULL) {
916	if (cmdp->cmdtype == CMDFUNCTION) {
917	*pp = cmdp->next;
918	freefunc(cmdp->param.func);
919	ckfree(cmdp);
920	} else {
921	pp = &cmdp->next;
922	}
923	}
924	}
925	INTON;
926	}
927
928
929
930	/*
931	* Locate a command in the command hash table. If "add" is nonzero,
932	* add the command to the table if it is not already present. The
933	* variable "lastcmdentry" is set to point to the address of the link
934	* pointing to the entry, so that delete_cmd_entry can delete the
935	* entry.
936	*/
937
938	struct tblentry **lastcmdentry;
939
940
941	STATIC struct tblentry *
942	cmdlookup(shinstance psh, const char name, int add)
943	{
944	int hashval;
945	const char *p;
946	struct tblentry *cmdp;
947	struct tblentry **pp;
948
949	p = name;
950	hashval = *p << 4;
951	while (*p)
952	hashval += *p++;
953	hashval &= 0x7FFF;
954	pp = &psh->cmdtable[hashval % CMDTABLESIZE];
955	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
956	if (equal(cmdp->cmdname, name))
957	break;
958	pp = &cmdp->next;
959	}
960	if (add && cmdp == NULL) {
961	INTOFF;
962	cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
963	+ strlen(name) + 1);
964	cmdp->next = NULL;
965	cmdp->cmdtype = CMDUNKNOWN;
966	cmdp->rehash = 0;
967	strcpy(cmdp->cmdname, name);
968	INTON;
969	}
970	lastcmdentry = pp;
971	return cmdp;
972	}
973
974	/*
975	* Delete the command entry returned on the last lookup.
976	*/
977
978	STATIC void
979	delete_cmd_entry(shinstance *psh)
980	{
981	struct tblentry *cmdp;
982
983	INTOFF;
984	cmdp = *lastcmdentry;
985	*lastcmdentry = cmdp->next;
986	ckfree(cmdp);
987	INTON;
988	}
989
990
991
992	#ifdef notdef
993	void
994	getcmdentry(shinstance psh, char name, struct cmdentry *entry)
995	{
996	struct tblentry *cmdp = cmdlookup(psh, name, 0);
997
998	if (cmdp) {
999	entry->u = cmdp->param;
1000	entry->cmdtype = cmdp->cmdtype;
1001	} else {
1002	entry->cmdtype = CMDUNKNOWN;
1003	entry->u.index = 0;
1004	}
1005	}
1006	#endif
1007
1008
1009	/*
1010	* Add a new command entry, replacing any existing command entry for
1011	* the same name - except special builtins.
1012	*/
1013
1014	STATIC void
1015	addcmdentry(shinstance psh, char name, struct cmdentry *entry)
1016	{
1017	struct tblentry *cmdp;
1018
1019	INTOFF;
1020	cmdp = cmdlookup(psh, name, 1);
1021	if (cmdp->cmdtype != CMDSPLBLTIN) {
1022	if (cmdp->cmdtype == CMDFUNCTION) {
1023	freefunc(cmdp->param.func);
1024	}
1025	cmdp->cmdtype = entry->cmdtype;
1026	cmdp->param = entry->u;
1027	}
1028	INTON;
1029	}
1030
1031
1032	/*
1033	* Define a shell function.
1034	*/
1035
1036	void
1037	defun(shinstance psh,char name, union node *func)
1038	{
1039	struct cmdentry entry;
1040
1041	INTOFF;
1042	entry.cmdtype = CMDFUNCTION;
1043	entry.u.func = copyfunc(func);
1044	addcmdentry(psh, name, &entry);
1045	INTON;
1046	}
1047
1048
1049	/*
1050	* Delete a function if it exists.
1051	*/
1052
1053	int
1054	unsetfunc(shinstance psh, char name)
1055	{
1056	struct tblentry *cmdp;
1057
1058	if ((cmdp = cmdlookup(psh, name, 0)) != NULL &&
1059	cmdp->cmdtype == CMDFUNCTION) {
1060	freefunc(cmdp->param.func);
1061	delete_cmd_entry(psh);
1062	return (0);
1063	}
1064	return (1);
1065	}
1066
1067	/*
1068	* Locate and print what a word is...
1069	* also used for 'command -[v\|V]'
1070	*/
1071
1072	int
1073	typecmd(shinstance psh, int argc, char *argv)
1074	{
1075	struct cmdentry entry;
1076	struct tblentry *cmdp;
1077	char * const *pp;
1078	struct alias *ap;
1079	int err = 0;
1080	char *arg;
1081	int c;
1082	int V_flag = 0;
1083	int v_flag = 0;
1084	int p_flag = 0;
1085
1086	while ((c = nextopt(psh, "vVp")) != 0) {
1087	switch (c) {
1088	case 'v': v_flag = 1; break;
1089	case 'V': V_flag = 1; break;
1090	case 'p': p_flag = 1; break;
1091	}
1092	}
1093
1094	if (p_flag && (v_flag \|\| V_flag))
1095	error(psh, "cannot specify -p with -v or -V");
1096
1097	while ((arg = *psh->argptr++)) {
1098	if (!v_flag)
1099	out1str(psh, arg);
1100	/* First look at the keywords */
1101	for (pp = parsekwd; *pp; pp++)
1102	if (*pp == arg && equal(*pp, arg))
1103	break;
1104
1105	if (*pp) {
1106	if (v_flag)
1107	err = 1;
1108	else
1109	out1str(psh, " is a shell keyword\n");
1110	continue;
1111	}
1112
1113	/* Then look at the aliases */
1114	if ((ap = lookupalias(psh, arg, 1)) != NULL) {
1115	if (!v_flag)
1116	out1fmt(psh, " is an alias for \n");
1117	out1fmt(psh, "%s\n", ap->val);
1118	continue;
1119	}
1120
1121	/* Then check if it is a tracked alias */
1122	if ((cmdp = cmdlookup(psh, arg, 0)) != NULL) {
1123	entry.cmdtype = cmdp->cmdtype;
1124	entry.u = cmdp->param;
1125	} else {
1126	/* Finally use brute force */
1127	find_command(psh, arg, &entry, DO_ABS, pathval(psh));
1128	}
1129
1130	switch (entry.cmdtype) {
1131	case CMDNORMAL: {
1132	if (strchr(arg, '/') == NULL) {
1133	const char *path = pathval(psh);
1134	char *name;
1135	int j = entry.u.index;
1136	do {
1137	name = padvance(psh, &path, arg);
1138	stunalloc(psh, name);
1139	} while (--j >= 0);
1140	if (!v_flag)
1141	out1fmt(psh, " is%s ",
1142	cmdp ? " a tracked alias for" : "");
1143	out1fmt(psh, "%s\n", name);
1144	} else {
1145	if (access(arg, X_OK) == 0) {
1146	if (!v_flag)
1147	out1fmt(psh, " is ");
1148	out1fmt(psh, "%s\n", arg);
1149	} else {
1150	if (!v_flag)
1151	out1fmt(psh, ": %s\n",
1152	strerror(errno));
1153	else
1154	err = 126;
1155	}
1156	}
1157	break;
1158	}
1159	case CMDFUNCTION:
1160	if (!v_flag)
1161	out1str(psh, " is a shell function\n");
1162	else
1163	out1fmt(psh, "%s\n", arg);
1164	break;
1165
1166	case CMDBUILTIN:
1167	if (!v_flag)
1168	out1str(psh, " is a shell builtin\n");
1169	else
1170	out1fmt(psh, "%s\n", arg);
1171	break;
1172
1173	case CMDSPLBLTIN:
1174	if (!v_flag)
1175	out1str(psh, " is a special shell builtin\n");
1176	else
1177	out1fmt(psh, "%s\n", arg);
1178	break;
1179
1180	default:
1181	if (!v_flag)
1182	out1str(psh, ": not found\n");
1183	err = 127;
1184	break;
1185	}
1186	}
1187	return err;
1188	}

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source: kBuild/trunk/src/kash/exec.c@ 1203

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