exec.c@ 2784

Last change on this file since 2784 was 2652, checked in by bird, 12 years ago
kash: Fixes for hash-bang-scripts on windows. Related debug tracing fix. Another CWD slash fix. Fixed a couple of assertions.
Property svn:eol-style set to `LF` Property svn:keywords set to `Id`
File size: 28.1 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	#ifdef EXEC_HASH_BANG_SCRIPT
231
232	/*
233	* Checks if NAME is the (base) name of the shell executable or something
234	* very similar.
235	*/
236	STATIC int
237	is_shell_exe_name(const char *name)
238	{
239	return equal(name, "kmk_ash")
240	\|\| equal(name, "kmk_sh")
241	\|\| equal(name, "kash")
242	\|\| equal(name, "sh");
243	}
244
245	/*
246	* Execute an interpreter introduced by "#!", for systems where this
247	* feature has not been built into the kernel. If the interpreter is
248	* the shell, return (effectively ignoring the "#!"). If the execution
249	* of the interpreter fails, exit.
250	*
251	* This code peeks inside the input buffer in order to avoid actually
252	* reading any input. It would benefit from a rewrite.
253	*/
254
255	#define NEWARGS 16
256
257	STATIC void
258	execinterp(shinstance psh, char argv, char *envp)
259	{
260	int n;
261	char *inp;
262	char *outp;
263	char c;
264	char *p;
265	char **ap;
266	char *newargs[NEWARGS];
267	intptr_t i;
268	char **ap2;
269	char **new;
270
271	/* Split the string into arguments. */
272	n = psh->parsenleft - 2;
273	inp = psh->parsenextc + 2;
274	ap = newargs;
275	for (;;) {
276	while (--n >= 0 && (inp == ' ' \|\| inp == '\t'))
277	inp++;
278	if (n < 0)
279	goto bad;
280	if ((c = *inp++) == '\n')
281	break;
282	if (ap == &newargs[NEWARGS])
283	bad: error(psh, "Bad #! line");
284	STARTSTACKSTR(psh, outp);
285	do {
286	STPUTC(psh, c, outp);
287	} while (--n >= 0 && (c = *inp++) != ' ' && c != '\t' && c != '\n');
288	STPUTC(psh, '\0', outp);
289	n++, inp--;
290	*ap++ = grabstackstr(psh, outp);
291	}
292
293	/* /usr/bin/env emulation, very common with kash/kmk_ash. */
294	i = ap - newargs;
295	if (i > 1 && equal(newargs[0], "/usr/bin/env")) {
296	if ( !strchr(newargs[1], '=')
297	&& newargs[1][0] != '-') {
298	/* shellexec below searches the PATH for us, so just
299	drop /usr/bin/env. */
300	TRACE((psh, "hash bang /usr/bin/env utility, dropping /usr/bin/env\n"));
301	ap--;
302	i--;
303	for (n = 0; n < i; n++)
304	newargs[n] = newargs[n + 1];
305	} /* else: complicated invocation */
306	}
307
308	/* If the interpreter is the shell or a similar shell, there is
309	no need to exec. */
310	if (i == 1) {
311	p = strrchr(newargs[0], '/');
312	if (!p)
313	p = newargs[0];
314	if (is_shell_exe_name(p)) {
315	TRACE((psh, "hash bang self\n"));
316	return;
317	}
318	}
319
320	/* Combine the two argument lists and exec. */
321	i = (char )ap - (char )newargs; /* size in bytes */
322	if (i == 0)
323	error(psh, "Bad #! line");
324	for (ap2 = argv ; *ap2++ != NULL ; );
325	new = ckmalloc(psh, i + ((char )ap2 - (char )argv));
326	ap = newargs, ap2 = new;
327	while ((i -= sizeof (char **)) >= 0)
328	ap2++ = ap++;
329	ap = argv;
330	while ((ap2++ = ap++))
331	/* nothing*/;
332	TRACE((psh, "hash bang '%s'\n", new[0]));
333	shellexec(psh, new, envp, pathval(psh), 0, 0);
334	/* NOTREACHED */
335	}
336
337	#endif /* EXEC_HASH_BANG_SCRIPT */
338
339
340	/*
341	* Do a path search. The variable path (passed by reference) should be
342	* set to the start of the path before the first call; padvance will update
343	* this value as it proceeds. Successive calls to padvance will return
344	* the possible path expansions in sequence. If an option (indicated by
345	* a percent sign) appears in the path entry then the global variable
346	* psh->pathopt will be set to point to it; otherwise psh->pathopt will be set to
347	* NULL.
348	*/
349
350	//const char *pathopt;
351
352	char *
353	padvance(shinstance psh, const char path, const char name)
354	{
355	const char *p;
356	char *q;
357	const char *start;
358	int len;
359
360	if (*path == NULL)
361	return NULL;
362	start = *path;
363	#ifdef PC_PATH_SEP
364	for (p = start ; p && p != ';' && *p != '%' ; p++);
365	#else
366	for (p = start ; p && p != ':' && *p != '%' ; p++);
367	#endif
368	len = (int)(p - start + strlen(name) + 2); /* "2" is for '/' and '\0' */
369	#ifdef PC_EXE_EXTS
370	len += 4; /* "4" is for .exe/.com/.cmd/.bat/.btm */
371	#endif
372	while (stackblocksize(psh) < len)
373	growstackblock(psh);
374	q = stackblock(psh);
375	if (p != start) {
376	memcpy(q, start, p - start);
377	q += p - start;
378	*q++ = '/';
379	}
380	strcpy(q, name);
381	psh->pathopt = NULL;
382	if (*p == '%') {
383	psh->pathopt = ++p;
384	#ifdef PC_PATH_SEP
385	while (p && p != ';') p++;
386	#else
387	while (p && p != ':') p++;
388	#endif
389	}
390	#ifdef PC_PATH_SEP
391	if (*p == ';')
392	#else
393	if (*p == ':')
394	#endif
395	*path = p + 1;
396	else
397	*path = NULL;
398	return stalloc(psh, len);
399	}
400
401
402	#ifdef PC_EXE_EXTS
403	STATIC int stat_pc_exec_exts(shinstance psh, char fullname, struct stat *st, int has_ext)
404	{
405	/* skip the SYSV crap */
406	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
407	return 0;
408	if (!has_ext && errno == ENOENT)
409	{
410	char *psz = strchr(fullname, '\0');
411	memcpy(psz, ".exe", 5);
412	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
413	return 0;
414	if (errno != ENOENT && errno != ENOTDIR)
415	return -1;
416
417	memcpy(psz, ".cmd", 5);
418	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
419	return 0;
420	if (errno != ENOENT && errno != ENOTDIR)
421	return -1;
422
423	memcpy(psz, ".bat", 5);
424	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
425	return 0;
426	if (errno != ENOENT && errno != ENOTDIR)
427	return -1;
428
429	memcpy(psz, ".com", 5);
430	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
431	return 0;
432	if (errno != ENOENT && errno != ENOTDIR)
433	return -1;
434
435	memcpy(psz, ".btm", 5);
436	if (shfile_stat(&psh->fdtab, fullname, st) >= 0)
437	return 0;
438	*psz = '\0';
439	}
440	return -1;
441	}
442	#endif /* PC_EXE_EXTS */
443
444
445
446	/* Command hashing code */
447
448
449	int
450	hashcmd(shinstance psh, int argc, char *argv)
451	{
452	struct tblentry **pp;
453	struct tblentry *cmdp;
454	int c;
455	int verbose;
456	struct cmdentry entry;
457	char *name;
458
459	verbose = 0;
460	while ((c = nextopt(psh, "rv")) != '\0') {
461	if (c == 'r') {
462	clearcmdentry(psh, 0);
463	} else if (c == 'v') {
464	verbose++;
465	}
466	}
467	if (*psh->argptr == NULL) {
468	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
469	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
470	if (verbose \|\| cmdp->cmdtype == CMDNORMAL)
471	printentry(psh, cmdp, verbose);
472	}
473	}
474	return 0;
475	}
476	while ((name = *psh->argptr) != NULL) {
477	if ((cmdp = cmdlookup(psh, name, 0)) != NULL
478	&& (cmdp->cmdtype == CMDNORMAL
479	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0)))
480	delete_cmd_entry(psh);
481	find_command(psh, name, &entry, DO_ERR, pathval(psh));
482	if (verbose) {
483	if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
484	cmdp = cmdlookup(psh, name, 0);
485	printentry(psh, cmdp, verbose);
486	}
487	output_flushall(psh);
488	}
489	psh->argptr++;
490	}
491	return 0;
492	}
493
494
495	STATIC void
496	printentry(shinstance psh, struct tblentry cmdp, int verbose)
497	{
498	int idx;
499	const char *path;
500	char *name;
501
502	switch (cmdp->cmdtype) {
503	case CMDNORMAL:
504	idx = cmdp->param.index;
505	path = pathval(psh);
506	do {
507	name = padvance(psh, &path, cmdp->cmdname);
508	stunalloc(psh, name);
509	} while (--idx >= 0);
510	out1str(psh, name);
511	break;
512	case CMDSPLBLTIN:
513	out1fmt(psh, "special builtin %s", cmdp->cmdname);
514	break;
515	case CMDBUILTIN:
516	out1fmt(psh, "builtin %s", cmdp->cmdname);
517	break;
518	case CMDFUNCTION:
519	out1fmt(psh, "function %s", cmdp->cmdname);
520	if (verbose) {
521	struct procstat ps;
522	INTOFF;
523	commandtext(psh, &ps, cmdp->param.func);
524	INTON;
525	out1str(psh, "() { ");
526	out1str(psh, ps.cmd);
527	out1str(psh, "; }");
528	}
529	break;
530	default:
531	error(psh, "internal error: %s cmdtype %d", cmdp->cmdname, cmdp->cmdtype);
532	}
533	if (cmdp->rehash)
534	out1c(psh, '*');
535	out1c(psh, '\n');
536	}
537
538
539
540	/*
541	* Resolve a command name. If you change this routine, you may have to
542	* change the shellexec routine as well.
543	*/
544
545	void
546	find_command(shinstance psh, char name, struct cmdentry entry, int act, const char path)
547	{
548	struct tblentry *cmdp, loc_cmd;
549	int idx;
550	int prev;
551	char *fullname;
552	struct stat statb;
553	int e;
554	int (bltin)(shinstance,int,char **);
555
556	#ifdef PC_EXE_EXTS
557	int has_ext = (int)(strlen(name) - 4);
558	has_ext = has_ext > 0
559	&& name[has_ext] == '.'
560	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
561	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
562	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
563	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
564	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
565	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
566	name + has_ext + 1)
567	!= NULL;
568	#endif
569
570	/* If name contains a slash, don't use PATH or hash table */
571	if (strchr(name, '/') != NULL) {
572	if (act & DO_ABS) {
573	while (shfile_stat(&psh->fdtab, name, &statb) < 0) {
574	#ifdef SYSV
575	if (errno == EINTR)
576	continue;
577	#endif
578	if (errno != ENOENT && errno != ENOTDIR)
579	e = errno;
580	entry->cmdtype = CMDUNKNOWN;
581	entry->u.index = -1;
582	return;
583	}
584	entry->cmdtype = CMDNORMAL;
585	entry->u.index = -1;
586	return;
587	}
588	entry->cmdtype = CMDNORMAL;
589	entry->u.index = 0;
590	return;
591	}
592
593	if (path != pathval(psh))
594	act \|= DO_ALTPATH;
595
596	if (act & DO_ALTPATH && strstr(path, "%builtin") != NULL)
597	act \|= DO_ALTBLTIN;
598
599	/* If name is in the table, check answer will be ok */
600	if ((cmdp = cmdlookup(psh, name, 0)) != NULL) {
601	do {
602	switch (cmdp->cmdtype) {
603	case CMDNORMAL:
604	if (act & DO_ALTPATH) {
605	cmdp = NULL;
606	continue;
607	}
608	break;
609	case CMDFUNCTION:
610	if (act & DO_NOFUNC) {
611	cmdp = NULL;
612	continue;
613	}
614	break;
615	case CMDBUILTIN:
616	if ((act & DO_ALTBLTIN) \|\| psh->builtinloc >= 0) {
617	cmdp = NULL;
618	continue;
619	}
620	break;
621	}
622	/* if not invalidated by cd, we're done */
623	if (cmdp->rehash == 0)
624	goto success;
625	} while (0);
626	}
627
628	/* If %builtin not in path, check for builtin next */
629	if ((act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : psh->builtinloc < 0) &&
630	(bltin = find_builtin(psh, name)) != 0)
631	goto builtin_success;
632
633	/* We have to search path. */
634	prev = -1; /* where to start */
635	if (cmdp) { /* doing a rehash */
636	if (cmdp->cmdtype == CMDBUILTIN)
637	prev = psh->builtinloc;
638	else
639	prev = cmdp->param.index;
640	}
641
642	e = ENOENT;
643	idx = -1;
644	loop:
645	while ((fullname = padvance(psh, &path, name)) != NULL) {
646	stunalloc(psh, fullname);
647	idx++;
648	if (psh->pathopt) {
649	if (prefix("builtin", psh->pathopt)) {
650	if ((bltin = find_builtin(psh, name)) == 0)
651	goto loop;
652	goto builtin_success;
653	} else if (prefix("func", psh->pathopt)) {
654	/* handled below */
655	} else {
656	/* ignore unimplemented options */
657	goto loop;
658	}
659	}
660	/* if rehash, don't redo absolute path names */
661	if (fullname[0] == '/' && idx <= prev) {
662	if (idx < prev)
663	goto loop;
664	TRACE((psh, "searchexec \"%s\": no change\n", name));
665	goto success;
666	}
667	#ifdef PC_EXE_EXTS
668	while (stat_pc_exec_exts(psh, fullname, &statb, has_ext) < 0) {
669	#else
670	while (shfile_stat(&psh->fdtab, fullname, &statb) < 0) {
671	#endif
672	#ifdef SYSV
673	if (errno == EINTR)
674	continue;
675	#endif
676	if (errno != ENOENT && errno != ENOTDIR)
677	e = errno;
678
679	goto loop;
680	}
681	e = EACCES; /* if we fail, this will be the error */
682	if (!S_ISREG(statb.st_mode))
683	goto loop;
684	if (psh->pathopt) { /* this is a %func directory */
685	if (act & DO_NOFUNC)
686	goto loop;
687	stalloc(psh, strlen(fullname) + 1);
688	readcmdfile(psh, fullname);
689	if ((cmdp = cmdlookup(psh, name, 0)) == NULL \|\|
690	cmdp->cmdtype != CMDFUNCTION)
691	error(psh, "%s not defined in %s", name, fullname);
692	stunalloc(psh, fullname);
693	goto success;
694	}
695	#ifdef notdef
696	/* XXX this code stops root executing stuff, and is buggy
697	if you need a group from the group list. */
698	if (statb.st_uid == sh_geteuid(psh)) {
699	if ((statb.st_mode & 0100) == 0)
700	goto loop;
701	} else if (statb.st_gid == sh_getegid(psh)) {
702	if ((statb.st_mode & 010) == 0)
703	goto loop;
704	} else {
705	if ((statb.st_mode & 01) == 0)
706	goto loop;
707	}
708	#endif
709	TRACE((psh, "searchexec \"%s\" returns \"%s\"\n", name, fullname));
710	INTOFF;
711	if (act & DO_ALTPATH) {
712	stalloc(psh, strlen(fullname) + 1);
713	cmdp = &loc_cmd;
714	} else
715	cmdp = cmdlookup(psh, name, 1);
716	cmdp->cmdtype = CMDNORMAL;
717	cmdp->param.index = idx;
718	INTON;
719	goto success;
720	}
721
722	/* We failed. If there was an entry for this command, delete it */
723	if (cmdp)
724	delete_cmd_entry(psh);
725	if (act & DO_ERR)
726	outfmt(psh->out2, "%s: %s\n", name, errmsg(psh, e, E_EXEC));
727	entry->cmdtype = CMDUNKNOWN;
728	return;
729
730	builtin_success:
731	INTOFF;
732	if (act & DO_ALTPATH)
733	cmdp = &loc_cmd;
734	else
735	cmdp = cmdlookup(psh, name, 1);
736	if (cmdp->cmdtype == CMDFUNCTION)
737	/* DO_NOFUNC must have been set */
738	cmdp = &loc_cmd;
739	cmdp->cmdtype = CMDBUILTIN;
740	cmdp->param.bltin = bltin;
741	INTON;
742	success:
743	cmdp->rehash = 0;
744	entry->cmdtype = cmdp->cmdtype;
745	entry->u = cmdp->param;
746	}
747
748
749
750	/*
751	* Search the table of builtin commands.
752	*/
753
754	int
755	(find_builtin(shinstance psh, char name))(shinstance psh, int, char **)
756	{
757	const struct builtincmd *bp;
758
759	for (bp = builtincmd ; bp->name ; bp++) {
760	if (bp->name == name && equal(bp->name, name))
761	return bp->builtin;
762	}
763	return 0;
764	}
765
766	int
767	(find_splbltin(shinstance psh, char name))(shinstance psh, int, char **)
768	{
769	const struct builtincmd *bp;
770
771	for (bp = splbltincmd ; bp->name ; bp++) {
772	if (bp->name == name && equal(bp->name, name))
773	return bp->builtin;
774	}
775	return 0;
776	}
777
778	/*
779	* At shell startup put special builtins into hash table.
780	* ensures they are executed first (see posix).
781	* We stop functions being added with the same name
782	* (as they are impossible to call)
783	*/
784
785	void
786	hash_special_builtins(shinstance *psh)
787	{
788	const struct builtincmd *bp;
789	struct tblentry *cmdp;
790
791	for (bp = splbltincmd ; bp->name ; bp++) {
792	cmdp = cmdlookup(psh, bp->name, 1);
793	cmdp->cmdtype = CMDSPLBLTIN;
794	cmdp->param.bltin = bp->builtin;
795	}
796	}
797
798
799
800	/*
801	* Called when a cd is done. Marks all commands so the next time they
802	* are executed they will be rehashed.
803	*/
804
805	void
806	hashcd(shinstance *psh)
807	{
808	struct tblentry **pp;
809	struct tblentry *cmdp;
810
811	for (pp = psh->cmdtable ; pp < &psh->cmdtable[CMDTABLESIZE] ; pp++) {
812	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
813	if (cmdp->cmdtype == CMDNORMAL
814	\|\| (cmdp->cmdtype == CMDBUILTIN && psh->builtinloc >= 0))
815	cmdp->rehash = 1;
816	}
817	}
818	}
819
820
821
822	/*
823	* Fix command hash table when PATH changed.
824	* Called before PATH is changed. The argument is the new value of PATH;
825	* pathval(psh) still returns the old value at this point.
826	* Called with interrupts off.
827	*/
828
829	void
830	changepath(shinstance psh, const char newval)
831	{
832	const char old, new;
833	int idx;
834	int firstchange;
835	int bltin;
836
837	old = pathval(psh);
838	new = newval;
839	firstchange = 9999; /* assume no change */
840	idx = 0;
841	bltin = -1;
842	for (;;) {
843	if (old != new) {
844	firstchange = idx;
845	#ifdef PC_PATH_SEP
846	if ((old == '\0' && new == ';')
847	\|\| (old == ';' && new == '\0'))
848	#else
849	if ((old == '\0' && new == ':')
850	\|\| (old == ':' && new == '\0'))
851	#endif
852	firstchange++;
853	old = new; /* ignore subsequent differences */
854	}
855	if (*new == '\0')
856	break;
857	if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
858	bltin = idx;
859	#ifdef PC_PATH_SEP
860	if (*new == ';') {
861	#else
862	if (*new == ':') {
863	#endif
864	idx++;
865	}
866	new++, old++;
867	}
868	if (psh->builtinloc < 0 && bltin >= 0)
869	psh->builtinloc = bltin; /* zap builtins */
870	if (psh->builtinloc >= 0 && bltin < 0)
871	firstchange = 0;
872	clearcmdentry(psh, firstchange);
873	psh->builtinloc = bltin;
874	}
875
876
877	/*
878	* Clear out command entries. The argument specifies the first entry in
879	* PATH which has changed.
880	*/
881
882	STATIC void
883	clearcmdentry(shinstance *psh, int firstchange)
884	{
885	struct tblentry **tblp;
886	struct tblentry **pp;
887	struct tblentry *cmdp;
888
889	INTOFF;
890	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
891	pp = tblp;
892	while ((cmdp = *pp) != NULL) {
893	if ((cmdp->cmdtype == CMDNORMAL &&
894	cmdp->param.index >= firstchange)
895	\|\| (cmdp->cmdtype == CMDBUILTIN &&
896	psh->builtinloc >= firstchange)) {
897	*pp = cmdp->next;
898	ckfree(psh, cmdp);
899	} else {
900	pp = &cmdp->next;
901	}
902	}
903	}
904	INTON;
905	}
906
907
908	/*
909	* Delete all functions.
910	*/
911
912	#ifdef mkinit
913	MKINIT void deletefuncs(struct shinstance *);
914	MKINIT void hash_special_builtins(struct shinstance *);
915
916	INIT {
917	hash_special_builtins(psh);
918	}
919
920	SHELLPROC {
921	deletefuncs(psh);
922	}
923	#endif
924
925	void
926	deletefuncs(shinstance *psh)
927	{
928	struct tblentry **tblp;
929	struct tblentry **pp;
930	struct tblentry *cmdp;
931
932	INTOFF;
933	for (tblp = psh->cmdtable ; tblp < &psh->cmdtable[CMDTABLESIZE] ; tblp++) {
934	pp = tblp;
935	while ((cmdp = *pp) != NULL) {
936	if (cmdp->cmdtype == CMDFUNCTION) {
937	*pp = cmdp->next;
938	freefunc(psh, cmdp->param.func);
939	ckfree(psh, cmdp);
940	} else {
941	pp = &cmdp->next;
942	}
943	}
944	}
945	INTON;
946	}
947
948
949
950	/*
951	* Locate a command in the command hash table. If "add" is nonzero,
952	* add the command to the table if it is not already present. The
953	* variable "lastcmdentry" is set to point to the address of the link
954	* pointing to the entry, so that delete_cmd_entry can delete the
955	* entry.
956	*/
957
958	struct tblentry **lastcmdentry;
959
960
961	STATIC struct tblentry *
962	cmdlookup(shinstance psh, const char name, int add)
963	{
964	int hashval;
965	const char *p;
966	struct tblentry *cmdp;
967	struct tblentry **pp;
968
969	p = name;
970	hashval = *p << 4;
971	while (*p)
972	hashval += *p++;
973	hashval &= 0x7FFF;
974	pp = &psh->cmdtable[hashval % CMDTABLESIZE];
975	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
976	if (equal(cmdp->cmdname, name))
977	break;
978	pp = &cmdp->next;
979	}
980	if (add && cmdp == NULL) {
981	INTOFF;
982	cmdp = *pp = ckmalloc(psh, sizeof (struct tblentry) - ARB
983	+ strlen(name) + 1);
984	cmdp->next = NULL;
985	cmdp->cmdtype = CMDUNKNOWN;
986	cmdp->rehash = 0;
987	strcpy(cmdp->cmdname, name);
988	INTON;
989	}
990	lastcmdentry = pp;
991	return cmdp;
992	}
993
994	/*
995	* Delete the command entry returned on the last lookup.
996	*/
997
998	STATIC void
999	delete_cmd_entry(shinstance *psh)
1000	{
1001	struct tblentry *cmdp;
1002
1003	INTOFF;
1004	cmdp = *lastcmdentry;
1005	*lastcmdentry = cmdp->next;
1006	ckfree(psh, cmdp);
1007	INTON;
1008	}
1009
1010
1011
1012	#ifdef notdef
1013	void
1014	getcmdentry(shinstance psh, char name, struct cmdentry *entry)
1015	{
1016	struct tblentry *cmdp = cmdlookup(psh, name, 0);
1017
1018	if (cmdp) {
1019	entry->u = cmdp->param;
1020	entry->cmdtype = cmdp->cmdtype;
1021	} else {
1022	entry->cmdtype = CMDUNKNOWN;
1023	entry->u.index = 0;
1024	}
1025	}
1026	#endif
1027
1028
1029	/*
1030	* Add a new command entry, replacing any existing command entry for
1031	* the same name - except special builtins.
1032	*/
1033
1034	STATIC void
1035	addcmdentry(shinstance psh, char name, struct cmdentry *entry)
1036	{
1037	struct tblentry *cmdp;
1038
1039	INTOFF;
1040	cmdp = cmdlookup(psh, name, 1);
1041	if (cmdp->cmdtype != CMDSPLBLTIN) {
1042	if (cmdp->cmdtype == CMDFUNCTION) {
1043	freefunc(psh, cmdp->param.func);
1044	}
1045	cmdp->cmdtype = entry->cmdtype;
1046	cmdp->param = entry->u;
1047	}
1048	INTON;
1049	}
1050
1051
1052	/*
1053	* Define a shell function.
1054	*/
1055
1056	void
1057	defun(shinstance psh, char name, union node *func)
1058	{
1059	struct cmdentry entry;
1060
1061	INTOFF;
1062	entry.cmdtype = CMDFUNCTION;
1063	entry.u.func = copyfunc(psh, func);
1064	addcmdentry(psh, name, &entry);
1065	INTON;
1066	}
1067
1068
1069	/*
1070	* Delete a function if it exists.
1071	*/
1072
1073	int
1074	unsetfunc(shinstance psh, char name)
1075	{
1076	struct tblentry *cmdp;
1077
1078	if ((cmdp = cmdlookup(psh, name, 0)) != NULL &&
1079	cmdp->cmdtype == CMDFUNCTION) {
1080	freefunc(psh, cmdp->param.func);
1081	delete_cmd_entry(psh);
1082	return (0);
1083	}
1084	return (1);
1085	}
1086
1087	/*
1088	* Locate and print what a word is...
1089	* also used for 'command -[v\|V]'
1090	*/
1091
1092	int
1093	typecmd(shinstance psh, int argc, char *argv)
1094	{
1095	struct cmdentry entry;
1096	struct tblentry *cmdp;
1097	char * const *pp;
1098	struct alias *ap;
1099	int err = 0;
1100	char *arg;
1101	int c;
1102	int V_flag = 0;
1103	int v_flag = 0;
1104	int p_flag = 0;
1105
1106	while ((c = nextopt(psh, "vVp")) != 0) {
1107	switch (c) {
1108	case 'v': v_flag = 1; break;
1109	case 'V': V_flag = 1; break;
1110	case 'p': p_flag = 1; break;
1111	}
1112	}
1113
1114	if (p_flag && (v_flag \|\| V_flag))
1115	error(psh, "cannot specify -p with -v or -V");
1116
1117	while ((arg = *psh->argptr++)) {
1118	if (!v_flag)
1119	out1str(psh, arg);
1120	/* First look at the keywords */
1121	for (pp = parsekwd; *pp; pp++)
1122	if (*pp == arg && equal(*pp, arg))
1123	break;
1124
1125	if (*pp) {
1126	if (v_flag)
1127	err = 1;
1128	else
1129	out1str(psh, " is a shell keyword\n");
1130	continue;
1131	}
1132
1133	/* Then look at the aliases */
1134	if ((ap = lookupalias(psh, arg, 1)) != NULL) {
1135	if (!v_flag)
1136	out1fmt(psh, " is an alias for \n");
1137	out1fmt(psh, "%s\n", ap->val);
1138	continue;
1139	}
1140
1141	/* Then check if it is a tracked alias */
1142	if ((cmdp = cmdlookup(psh, arg, 0)) != NULL) {
1143	entry.cmdtype = cmdp->cmdtype;
1144	entry.u = cmdp->param;
1145	} else {
1146	/* Finally use brute force */
1147	find_command(psh, arg, &entry, DO_ABS, pathval(psh));
1148	}
1149
1150	switch (entry.cmdtype) {
1151	case CMDNORMAL: {
1152	if (strchr(arg, '/') == NULL) {
1153	const char *path = pathval(psh);
1154	char *name;
1155	int j = entry.u.index;
1156	do {
1157	name = padvance(psh, &path, arg);
1158	stunalloc(psh, name);
1159	} while (--j >= 0);
1160	if (!v_flag)
1161	out1fmt(psh, " is%s ",
1162	cmdp ? " a tracked alias for" : "");
1163	out1fmt(psh, "%s\n", name);
1164	} else {
1165	if (shfile_access(&psh->fdtab, arg, X_OK) == 0) {
1166	if (!v_flag)
1167	out1fmt(psh, " is ");
1168	out1fmt(psh, "%s\n", arg);
1169	} else {
1170	if (!v_flag)
1171	out1fmt(psh, ": %s\n",
1172	sh_strerror(psh, errno));
1173	else
1174	err = 126;
1175	}
1176	}
1177	break;
1178	}
1179	case CMDFUNCTION:
1180	if (!v_flag)
1181	out1str(psh, " is a shell function\n");
1182	else
1183	out1fmt(psh, "%s\n", arg);
1184	break;
1185
1186	case CMDBUILTIN:
1187	if (!v_flag)
1188	out1str(psh, " is a shell builtin\n");
1189	else
1190	out1fmt(psh, "%s\n", arg);
1191	break;
1192
1193	case CMDSPLBLTIN:
1194	if (!v_flag)
1195	out1str(psh, " is a special shell builtin\n");
1196	else
1197	out1fmt(psh, "%s\n", arg);
1198	break;
1199
1200	default:
1201	if (!v_flag)
1202	out1str(psh, ": not found\n");
1203	err = 127;
1204	break;
1205	}
1206	}
1207	return err;
1208	}

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source: kBuild/trunk/src/kash/exec.c@ 2784

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