exec.c@ 2438

Last change on this file since 2438 was 2298, checked in by bird, 16 years ago
kash: no return indicators that works for both gcc and msc (not pretty, but wtf).
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 5
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	if (ap == newargs + 1) { /* if no args, maybe no exec is needed */
279	p = newargs[0];
280	for (;;) {
281	if (equal(p, "sh") \|\| equal(p, "ash")) {
282	TRACE((psh, "hash bang self\n"));
283	return;
284	}
285	while (*p != '/') {
286	if (*p == '\0')
287	goto break2;
288	p++;
289	}
290	p++;
291	}
292	break2:;
293	}
294	i = (char )ap - (char )newargs; /* size in bytes */
295	if (i == 0)
296	error(psh, "Bad #! line");
297	for (ap2 = argv ; *ap2++ != NULL ; );
298	new = ckmalloc(psh, i + ((char )ap2 - (char )argv));
299	ap = newargs, ap2 = new;
300	while ((i -= sizeof (char **)) >= 0)
301	ap2++ = ap++;
302	ap = argv;
303	while (ap2++ = ap++);
304	TRACE((psh, "hash bang '%s'\n", new[0]));
305	shellexec(psh, new, envp, pathval(psh), 0, 0);
306	/* NOTREACHED */
307	}
308	#endif
309
310
311
312	/*
313	* Do a path search. The variable path (passed by reference) should be
314	* set to the start of the path before the first call; padvance will update
315	* this value as it proceeds. Successive calls to padvance will return
316	* the possible path expansions in sequence. If an option (indicated by
317	* a percent sign) appears in the path entry then the global variable
318	* psh->pathopt will be set to point to it; otherwise psh->pathopt will be set to
319	* NULL.
320	*/
321
322	//const char *pathopt;
323
324	char *
325	padvance(shinstance psh, const char path, const char name)
326	{
327	const char *p;
328	char *q;
329	const char *start;
330	int len;
331
332	if (*path == NULL)
333	return NULL;
334	start = *path;
335	#ifdef PC_PATH_SEP
336	for (p = start ; p && p != ';' && *p != '%' ; p++);
337	#else
338	for (p = start ; p && p != ':' && *p != '%' ; p++);
339	#endif
340	len = (int)(p - start + strlen(name) + 2); /* "2" is for '/' and '\0' */
341	#ifdef PC_EXE_EXTS
342	len += 4; /* "4" is for .exe/.com/.cmd/.bat/.btm */
343	#endif
344	while (stackblocksize(psh) < len)
345	growstackblock(psh);
346	q = stackblock(psh);
347	if (p != start) {
348	memcpy(q, start, p - start);
349	q += p - start;
350	*q++ = '/';
351	}
352	strcpy(q, name);
353	psh->pathopt = NULL;
354	if (*p == '%') {
355	psh->pathopt = ++p;
356	#ifdef PC_PATH_SEP
357	while (p && p != ';') p++;
358	#else
359	while (p && p != ':') p++;
360	#endif
361	}
362	#ifdef PC_PATH_SEP
363	if (*p == ';')
364	#else
365	if (*p == ':')
366	#endif
367	*path = p + 1;
368	else
369	*path = NULL;
370	return stalloc(psh, len);
371	}
372
373
374	#ifdef PC_EXE_EXTS
375	STATIC int stat_pc_exec_exts(shinstance psh, char fullname, struct stat *st, int has_ext)
376	{
377	/* skip the SYSV crap */
378	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
379	return 0;
380	if (!has_ext && errno == ENOENT)
381	{
382	char *psz = strchr(fullname, '\0');
383	memcpy(psz, ".exe", 5);
384	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
385	return 0;
386	if (errno != ENOENT && errno != ENOTDIR)
387	return -1;
388
389	memcpy(psz, ".cmd", 5);
390	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
391	return 0;
392	if (errno != ENOENT && errno != ENOTDIR)
393	return -1;
394
395	memcpy(psz, ".bat", 5);
396	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
397	return 0;
398	if (errno != ENOENT && errno != ENOTDIR)
399	return -1;
400
401	memcpy(psz, ".com", 5);
402	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
403	return 0;
404	if (errno != ENOENT && errno != ENOTDIR)
405	return -1;
406
407	memcpy(psz, ".btm", 5);
408	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
409	return 0;
410	*psz = '\0';
411	}
412	return -1;
413	}
414	#endif /* PC_EXE_EXTS */
415
416
417
418	/* Command hashing code */
419
420
421	int
422	hashcmd(shinstance psh, int argc, char *argv)
423	{
424	struct tblentry **pp;
425	struct tblentry *cmdp;
426	int c;
427	int verbose;
428	struct cmdentry entry;
429	char *name;
430
431	verbose = 0;
432	while ((c = nextopt(psh, "rv")) != '\0') {
433	if (c == 'r') {
434	clearcmdentry(psh, 0);
435	} else if (c == 'v') {
436	verbose++;
437	}
438	}
439	if (*psh->argptr == NULL) {
440	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
441	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
442	if (verbose \|\| cmdp->cmdtype == CMDNORMAL)
443	printentry(psh, cmdp, verbose);
444	}
445	}
446	return 0;
447	}
448	while ((name = *psh->argptr) != NULL) {
449	if ((cmdp = cmdlookup(psh, name, 0)) != NULL
450	&& (cmdp->cmdtype == CMDNORMAL
451	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0)))
452	delete_cmd_entry(psh);
453	find_command(psh, name, &entry, DO_ERR, pathval(psh));
454	if (verbose) {
455	if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
456	cmdp = cmdlookup(psh, name, 0);
457	printentry(psh, cmdp, verbose);
458	}
459	output_flushall(psh);
460	}
461	psh->argptr++;
462	}
463	return 0;
464	}
465
466
467	STATIC void
468	printentry(shinstance psh, struct tblentry cmdp, int verbose)
469	{
470	int idx;
471	const char *path;
472	char *name;
473
474	switch (cmdp->cmdtype) {
475	case CMDNORMAL:
476	idx = cmdp->param.index;
477	path = pathval(psh);
478	do {
479	name = padvance(psh, &path, cmdp->cmdname);
480	stunalloc(psh, name);
481	} while (--idx >= 0);
482	out1str(psh, name);
483	break;
484	case CMDSPLBLTIN:
485	out1fmt(psh, "special builtin %s", cmdp->cmdname);
486	break;
487	case CMDBUILTIN:
488	out1fmt(psh, "builtin %s", cmdp->cmdname);
489	break;
490	case CMDFUNCTION:
491	out1fmt(psh, "function %s", cmdp->cmdname);
492	if (verbose) {
493	struct procstat ps;
494	INTOFF;
495	commandtext(psh, &ps, cmdp->param.func);
496	INTON;
497	out1str(psh, "() { ");
498	out1str(psh, ps.cmd);
499	out1str(psh, "; }");
500	}
501	break;
502	default:
503	error(psh, "internal error: %s cmdtype %d", cmdp->cmdname, cmdp->cmdtype);
504	}
505	if (cmdp->rehash)
506	out1c(psh, '*');
507	out1c(psh, '\n');
508	}
509
510
511
512	/*
513	* Resolve a command name. If you change this routine, you may have to
514	* change the shellexec routine as well.
515	*/
516
517	void
518	find_command(shinstance psh, char name, struct cmdentry entry, int act, const char path)
519	{
520	struct tblentry *cmdp, loc_cmd;
521	int idx;
522	int prev;
523	char *fullname;
524	struct stat statb;
525	int e;
526	int (bltin)(shinstance,int,char **);
527
528	#ifdef PC_EXE_EXTS
529	int has_ext = (int)(strlen(name) - 4);
530	has_ext = has_ext > 0
531	&& name[has_ext] == '.'
532	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
533	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
534	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
535	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
536	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
537	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
538	name + has_ext + 1)
539	!= NULL;
540	#endif
541
542	/* If name contains a slash, don't use PATH or hash table */
543	if (strchr(name, '/') != NULL) {
544	if (act & DO_ABS) {
545	while (shfile_stat(&psh->fdtab, name, &statb) < 0) {
546	#ifdef SYSV
547	if (errno == EINTR)
548	continue;
549	#endif
550	if (errno != ENOENT && errno != ENOTDIR)
551	e = errno;
552	entry->cmdtype = CMDUNKNOWN;
553	entry->u.index = -1;
554	return;
555	}
556	entry->cmdtype = CMDNORMAL;
557	entry->u.index = -1;
558	return;
559	}
560	entry->cmdtype = CMDNORMAL;
561	entry->u.index = 0;
562	return;
563	}
564
565	if (path != pathval(psh))
566	act \|= DO_ALTPATH;
567
568	if (act & DO_ALTPATH && strstr(path, "%builtin") != NULL)
569	act \|= DO_ALTBLTIN;
570
571	/* If name is in the table, check answer will be ok */
572	if ((cmdp = cmdlookup(psh, name, 0)) != NULL) {
573	do {
574	switch (cmdp->cmdtype) {
575	case CMDNORMAL:
576	if (act & DO_ALTPATH) {
577	cmdp = NULL;
578	continue;
579	}
580	break;
581	case CMDFUNCTION:
582	if (act & DO_NOFUNC) {
583	cmdp = NULL;
584	continue;
585	}
586	break;
587	case CMDBUILTIN:
588	if ((act & DO_ALTBLTIN) \|\| psh->builtinloc >= 0) {
589	cmdp = NULL;
590	continue;
591	}
592	break;
593	}
594	/* if not invalidated by cd, we're done */
595	if (cmdp->rehash == 0)
596	goto success;
597	} while (0);
598	}
599
600	/* If %builtin not in path, check for builtin next */
601	if ((act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : psh->builtinloc < 0) &&
602	(bltin = find_builtin(psh, name)) != 0)
603	goto builtin_success;
604
605	/* We have to search path. */
606	prev = -1; /* where to start */
607	if (cmdp) { /* doing a rehash */
608	if (cmdp->cmdtype == CMDBUILTIN)
609	prev = psh->builtinloc;
610	else
611	prev = cmdp->param.index;
612	}
613
614	e = ENOENT;
615	idx = -1;
616	loop:
617	while ((fullname = padvance(psh, &path, name)) != NULL) {
618	stunalloc(psh, fullname);
619	idx++;
620	if (psh->pathopt) {
621	if (prefix("builtin", psh->pathopt)) {
622	if ((bltin = find_builtin(psh, name)) == 0)
623	goto loop;
624	goto builtin_success;
625	} else if (prefix("func", psh->pathopt)) {
626	/* handled below */
627	} else {
628	/* ignore unimplemented options */
629	goto loop;
630	}
631	}
632	/* if rehash, don't redo absolute path names */
633	if (fullname[0] == '/' && idx <= prev) {
634	if (idx < prev)
635	goto loop;
636	TRACE((psh, "searchexec \"%s\": no change\n", name));
637	goto success;
638	}
639	#ifdef PC_EXE_EXTS
640	while (stat_pc_exec_exts(psh, fullname, &statb, has_ext) < 0) {
641	#else
642	while (shfile_stat(&psh->fdtab, fullname, &statb) < 0) {
643	#endif
644	#ifdef SYSV
645	if (errno == EINTR)
646	continue;
647	#endif
648	if (errno != ENOENT && errno != ENOTDIR)
649	e = errno;
650
651	goto loop;
652	}
653	e = EACCES; /* if we fail, this will be the error */
654	if (!S_ISREG(statb.st_mode))
655	goto loop;
656	if (psh->pathopt) { /* this is a %func directory */
657	if (act & DO_NOFUNC)
658	goto loop;
659	stalloc(psh, strlen(fullname) + 1);
660	readcmdfile(psh, fullname);
661	if ((cmdp = cmdlookup(psh, name, 0)) == NULL \|\|
662	cmdp->cmdtype != CMDFUNCTION)
663	error(psh, "%s not defined in %s", name, fullname);
664	stunalloc(psh, fullname);
665	goto success;
666	}
667	#ifdef notdef
668	/* XXX this code stops root executing stuff, and is buggy
669	if you need a group from the group list. */
670	if (statb.st_uid == sh_geteuid(psh)) {
671	if ((statb.st_mode & 0100) == 0)
672	goto loop;
673	} else if (statb.st_gid == sh_getegid(psh)) {
674	if ((statb.st_mode & 010) == 0)
675	goto loop;
676	} else {
677	if ((statb.st_mode & 01) == 0)
678	goto loop;
679	}
680	#endif
681	TRACE((psh, "searchexec \"%s\" returns \"%s\"\n", name, fullname));
682	INTOFF;
683	if (act & DO_ALTPATH) {
684	stalloc(psh, strlen(fullname) + 1);
685	cmdp = &loc_cmd;
686	} else
687	cmdp = cmdlookup(psh, name, 1);
688	cmdp->cmdtype = CMDNORMAL;
689	cmdp->param.index = idx;
690	INTON;
691	goto success;
692	}
693
694	/* We failed. If there was an entry for this command, delete it */
695	if (cmdp)
696	delete_cmd_entry(psh);
697	if (act & DO_ERR)
698	outfmt(psh->out2, "%s: %s\n", name, errmsg(psh, e, E_EXEC));
699	entry->cmdtype = CMDUNKNOWN;
700	return;
701
702	builtin_success:
703	INTOFF;
704	if (act & DO_ALTPATH)
705	cmdp = &loc_cmd;
706	else
707	cmdp = cmdlookup(psh, name, 1);
708	if (cmdp->cmdtype == CMDFUNCTION)
709	/* DO_NOFUNC must have been set */
710	cmdp = &loc_cmd;
711	cmdp->cmdtype = CMDBUILTIN;
712	cmdp->param.bltin = bltin;
713	INTON;
714	success:
715	cmdp->rehash = 0;
716	entry->cmdtype = cmdp->cmdtype;
717	entry->u = cmdp->param;
718	}
719
720
721
722	/*
723	* Search the table of builtin commands.
724	*/
725
726	int
727	(find_builtin(shinstance psh, char name))(shinstance psh, int, char **)
728	{
729	const struct builtincmd *bp;
730
731	for (bp = builtincmd ; bp->name ; bp++) {
732	if (bp->name == name && equal(bp->name, name))
733	return bp->builtin;
734	}
735	return 0;
736	}
737
738	int
739	(find_splbltin(shinstance psh, char name))(shinstance psh, int, char **)
740	{
741	const struct builtincmd *bp;
742
743	for (bp = splbltincmd ; bp->name ; bp++) {
744	if (bp->name == name && equal(bp->name, name))
745	return bp->builtin;
746	}
747	return 0;
748	}
749
750	/*
751	* At shell startup put special builtins into hash table.
752	* ensures they are executed first (see posix).
753	* We stop functions being added with the same name
754	* (as they are impossible to call)
755	*/
756
757	void
758	hash_special_builtins(shinstance *psh)
759	{
760	const struct builtincmd *bp;
761	struct tblentry *cmdp;
762
763	for (bp = splbltincmd ; bp->name ; bp++) {
764	cmdp = cmdlookup(psh, bp->name, 1);
765	cmdp->cmdtype = CMDSPLBLTIN;
766	cmdp->param.bltin = bp->builtin;
767	}
768	}
769
770
771
772	/*
773	* Called when a cd is done. Marks all commands so the next time they
774	* are executed they will be rehashed.
775	*/
776
777	void
778	hashcd(shinstance *psh)
779	{
780	struct tblentry **pp;
781	struct tblentry *cmdp;
782
783	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
784	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
785	if (cmdp->cmdtype == CMDNORMAL
786	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0))
787	cmdp->rehash = 1;
788	}
789	}
790	}
791
792
793
794	/*
795	* Fix command hash table when PATH changed.
796	* Called before PATH is changed. The argument is the new value of PATH;
797	* pathval(psh) still returns the old value at this point.
798	* Called with interrupts off.
799	*/
800
801	void
802	changepath(shinstance psh, const char newval)
803	{
804	const char old, new;
805	int idx;
806	int firstchange;
807	int bltin;
808
809	old = pathval(psh);
810	new = newval;
811	firstchange = 9999; /* assume no change */
812	idx = 0;
813	bltin = -1;
814	for (;;) {
815	if (old != new) {
816	firstchange = idx;
817	#ifdef PC_PATH_SEP
818	if ((old == '\0' && new == ';')
819	\|\| (old == ';' && new == '\0'))
820	#else
821	if ((old == '\0' && new == ':')
822	\|\| (old == ':' && new == '\0'))
823	#endif
824	firstchange++;
825	old = new; /* ignore subsequent differences */
826	}
827	if (*new == '\0')
828	break;
829	if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
830	bltin = idx;
831	#ifdef PC_PATH_SEP
832	if (*new == ';') {
833	#else
834	if (*new == ':') {
835	#endif
836	idx++;
837	}
838	new++, old++;
839	}
840	if (psh->builtinloc < 0 && bltin >= 0)
841	psh->builtinloc = bltin; /* zap builtins */
842	if (psh->builtinloc >= 0 && bltin < 0)
843	firstchange = 0;
844	clearcmdentry(psh, firstchange);
845	psh->builtinloc = bltin;
846	}
847
848
849	/*
850	* Clear out command entries. The argument specifies the first entry in
851	* PATH which has changed.
852	*/
853
854	STATIC void
855	clearcmdentry(shinstance *psh, int firstchange)
856	{
857	struct tblentry **tblp;
858	struct tblentry **pp;
859	struct tblentry *cmdp;
860
861	INTOFF;
862	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
863	pp = tblp;
864	while ((cmdp = *pp) != NULL) {
865	if ((cmdp->cmdtype == CMDNORMAL &&
866	cmdp->param.index >= firstchange)
867	\|\| (cmdp->cmdtype == CMDBUILTIN &&
868	psh->builtinloc >= firstchange)) {
869	*pp = cmdp->next;
870	ckfree(psh, cmdp);
871	} else {
872	pp = &cmdp->next;
873	}
874	}
875	}
876	INTON;
877	}
878
879
880	/*
881	* Delete all functions.
882	*/
883
884	#ifdef mkinit
885	MKINIT void deletefuncs(struct shinstance *);
886	MKINIT void hash_special_builtins(struct shinstance *);
887
888	INIT {
889	hash_special_builtins(psh);
890	}
891
892	SHELLPROC {
893	deletefuncs(psh);
894	}
895	#endif
896
897	void
898	deletefuncs(shinstance *psh)
899	{
900	struct tblentry **tblp;
901	struct tblentry **pp;
902	struct tblentry *cmdp;
903
904	INTOFF;
905	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
906	pp = tblp;
907	while ((cmdp = *pp) != NULL) {
908	if (cmdp->cmdtype == CMDFUNCTION) {
909	*pp = cmdp->next;
910	freefunc(psh, cmdp->param.func);
911	ckfree(psh, cmdp);
912	} else {
913	pp = &cmdp->next;
914	}
915	}
916	}
917	INTON;
918	}
919
920
921
922	/*
923	* Locate a command in the command hash table. If "add" is nonzero,
924	* add the command to the table if it is not already present. The
925	* variable "lastcmdentry" is set to point to the address of the link
926	* pointing to the entry, so that delete_cmd_entry can delete the
927	* entry.
928	*/
929
930	struct tblentry **lastcmdentry;
931
932
933	STATIC struct tblentry *
934	cmdlookup(shinstance psh, const char name, int add)
935	{
936	int hashval;
937	const char *p;
938	struct tblentry *cmdp;
939	struct tblentry **pp;
940
941	p = name;
942	hashval = *p << 4;
943	while (*p)
944	hashval += *p++;
945	hashval &= 0x7FFF;
946	pp = &psh->cmdtable[hashval % CMDTABLESIZE];
947	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
948	if (equal(cmdp->cmdname, name))
949	break;
950	pp = &cmdp->next;
951	}
952	if (add && cmdp == NULL) {
953	INTOFF;
954	cmdp = *pp = ckmalloc(psh, sizeof (struct tblentry) - ARB
955	+ strlen(name) + 1);
956	cmdp->next = NULL;
957	cmdp->cmdtype = CMDUNKNOWN;
958	cmdp->rehash = 0;
959	strcpy(cmdp->cmdname, name);
960	INTON;
961	}
962	lastcmdentry = pp;
963	return cmdp;
964	}
965
966	/*
967	* Delete the command entry returned on the last lookup.
968	*/
969
970	STATIC void
971	delete_cmd_entry(shinstance *psh)
972	{
973	struct tblentry *cmdp;
974
975	INTOFF;
976	cmdp = *lastcmdentry;
977	*lastcmdentry = cmdp->next;
978	ckfree(psh, cmdp);
979	INTON;
980	}
981
982
983
984	#ifdef notdef
985	void
986	getcmdentry(shinstance psh, char name, struct cmdentry *entry)
987	{
988	struct tblentry *cmdp = cmdlookup(psh, name, 0);
989
990	if (cmdp) {
991	entry->u = cmdp->param;
992	entry->cmdtype = cmdp->cmdtype;
993	} else {
994	entry->cmdtype = CMDUNKNOWN;
995	entry->u.index = 0;
996	}
997	}
998	#endif
999
1000
1001	/*
1002	* Add a new command entry, replacing any existing command entry for
1003	* the same name - except special builtins.
1004	*/
1005
1006	STATIC void
1007	addcmdentry(shinstance psh, char name, struct cmdentry *entry)
1008	{
1009	struct tblentry *cmdp;
1010
1011	INTOFF;
1012	cmdp = cmdlookup(psh, name, 1);
1013	if (cmdp->cmdtype != CMDSPLBLTIN) {
1014	if (cmdp->cmdtype == CMDFUNCTION) {
1015	freefunc(psh, cmdp->param.func);
1016	}
1017	cmdp->cmdtype = entry->cmdtype;
1018	cmdp->param = entry->u;
1019	}
1020	INTON;
1021	}
1022
1023
1024	/*
1025	* Define a shell function.
1026	*/
1027
1028	void
1029	defun(shinstance psh, char name, union node *func)
1030	{
1031	struct cmdentry entry;
1032
1033	INTOFF;
1034	entry.cmdtype = CMDFUNCTION;
1035	entry.u.func = copyfunc(psh, func);
1036	addcmdentry(psh, name, &entry);
1037	INTON;
1038	}
1039
1040
1041	/*
1042	* Delete a function if it exists.
1043	*/
1044
1045	int
1046	unsetfunc(shinstance psh, char name)
1047	{
1048	struct tblentry *cmdp;
1049
1050	if ((cmdp = cmdlookup(psh, name, 0)) != NULL &&
1051	cmdp->cmdtype == CMDFUNCTION) {
1052	freefunc(psh, cmdp->param.func);
1053	delete_cmd_entry(psh);
1054	return (0);
1055	}
1056	return (1);
1057	}
1058
1059	/*
1060	* Locate and print what a word is...
1061	* also used for 'command -[v\|V]'
1062	*/
1063
1064	int
1065	typecmd(shinstance psh, int argc, char *argv)
1066	{
1067	struct cmdentry entry;
1068	struct tblentry *cmdp;
1069	char * const *pp;
1070	struct alias *ap;
1071	int err = 0;
1072	char *arg;
1073	int c;
1074	int V_flag = 0;
1075	int v_flag = 0;
1076	int p_flag = 0;
1077
1078	while ((c = nextopt(psh, "vVp")) != 0) {
1079	switch (c) {
1080	case 'v': v_flag = 1; break;
1081	case 'V': V_flag = 1; break;
1082	case 'p': p_flag = 1; break;
1083	}
1084	}
1085
1086	if (p_flag && (v_flag \|\| V_flag))
1087	error(psh, "cannot specify -p with -v or -V");
1088
1089	while ((arg = *psh->argptr++)) {
1090	if (!v_flag)
1091	out1str(psh, arg);
1092	/* First look at the keywords */
1093	for (pp = parsekwd; *pp; pp++)
1094	if (*pp == arg && equal(*pp, arg))
1095	break;
1096
1097	if (*pp) {
1098	if (v_flag)
1099	err = 1;
1100	else
1101	out1str(psh, " is a shell keyword\n");
1102	continue;
1103	}
1104
1105	/* Then look at the aliases */
1106	if ((ap = lookupalias(psh, arg, 1)) != NULL) {
1107	if (!v_flag)
1108	out1fmt(psh, " is an alias for \n");
1109	out1fmt(psh, "%s\n", ap->val);
1110	continue;
1111	}
1112
1113	/* Then check if it is a tracked alias */
1114	if ((cmdp = cmdlookup(psh, arg, 0)) != NULL) {
1115	entry.cmdtype = cmdp->cmdtype;
1116	entry.u = cmdp->param;
1117	} else {
1118	/* Finally use brute force */
1119	find_command(psh, arg, &entry, DO_ABS, pathval(psh));
1120	}
1121
1122	switch (entry.cmdtype) {
1123	case CMDNORMAL: {
1124	if (strchr(arg, '/') == NULL) {
1125	const char *path = pathval(psh);
1126	char *name;
1127	int j = entry.u.index;
1128	do {
1129	name = padvance(psh, &path, arg);
1130	stunalloc(psh, name);
1131	} while (--j >= 0);
1132	if (!v_flag)
1133	out1fmt(psh, " is%s ",
1134	cmdp ? " a tracked alias for" : "");
1135	out1fmt(psh, "%s\n", name);
1136	} else {
1137	if (shfile_access(&psh->fdtab, arg, X_OK) == 0) {
1138	if (!v_flag)
1139	out1fmt(psh, " is ");
1140	out1fmt(psh, "%s\n", arg);
1141	} else {
1142	if (!v_flag)
1143	out1fmt(psh, ": %s\n",
1144	strerror(errno));
1145	else
1146	err = 126;
1147	}
1148	}
1149	break;
1150	}
1151	case CMDFUNCTION:
1152	if (!v_flag)
1153	out1str(psh, " is a shell function\n");
1154	else
1155	out1fmt(psh, "%s\n", arg);
1156	break;
1157
1158	case CMDBUILTIN:
1159	if (!v_flag)
1160	out1str(psh, " is a shell builtin\n");
1161	else
1162	out1fmt(psh, "%s\n", arg);
1163	break;
1164
1165	case CMDSPLBLTIN:
1166	if (!v_flag)
1167	out1str(psh, " is a special shell builtin\n");
1168	else
1169	out1fmt(psh, "%s\n", arg);
1170	break;
1171
1172	default:
1173	if (!v_flag)
1174	out1str(psh, ": not found\n");
1175	err = 127;
1176	break;
1177	}
1178	}
1179	return err;
1180	}

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source: kBuild/trunk/src/kash/exec.c@ 2438

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