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Last change on this file since 3466 was 3279, checked in by bird, 19 years ago
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[2460]	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	#include <sys/cdefs.h>
	36	#ifndef lint
	37	#if 0
	38	static char sccsid[] = "@(#)exec.c 8.4 (Berkeley) 6/8/95";
	39	#else
	40	__RCSID("$NetBSD: exec.c,v 1.37 2003/08/07 09:05:31 agc Exp $");
	41	#endif
	42	#endif /* not lint */
	43
	44	#include <sys/types.h>
	45	#include <sys/stat.h>
	46	#include <sys/wait.h>
	47	#include <unistd.h>
	48	#include <fcntl.h>
	49	#include <errno.h>
	50	#include <stdio.h>
	51	#include <stdlib.h>
	52
	53	/*
	54	* When commands are first encountered, they are entered in a hash table.
	55	* This ensures that a full path search will not have to be done for them
	56	* on each invocation.
	57	*
	58	* We should investigate converting to a linear search, even though that
	59	* would make the command name "hash" a misnomer.
	60	*/
	61
	62	#include "shell.h"
	63	#include "main.h"
	64	#include "nodes.h"
	65	#include "parser.h"
	66	#include "redir.h"
	67	#include "eval.h"
	68	#include "exec.h"
	69	#include "builtins.h"
	70	#include "var.h"
	71	#include "options.h"
	72	#include "input.h"
	73	#include "output.h"
	74	#include "syntax.h"
	75	#include "memalloc.h"
	76	#include "error.h"
	77	#include "init.h"
	78	#include "mystring.h"
	79	#include "show.h"
	80	#include "jobs.h"
	81	#include "alias.h"
[2463]	82	#ifdef __INNOTEK_LIBC__
	83	#include <InnoTekLIBC/backend.h>
	84	#endif
[2460]	85
	86
	87	#define CMDTABLESIZE 31 /* should be prime */
	88	#define ARB 1 /* actual size determined at run time */
	89
	90
	91
	92	struct tblentry {
	93	struct tblentry next; / next entry in hash chain */
	94	union param param; /* definition of builtin function */
	95	short cmdtype; /* index identifying command */
	96	char rehash; /* if set, cd done since entry created */
	97	char cmdname[ARB]; /* name of command */
	98	};
	99
	100
	101	STATIC struct tblentry *cmdtable[CMDTABLESIZE];
	102	STATIC int builtinloc = -1; /* index in path of %builtin, or -1 */
	103	int exerrno = 0; /* Last exec error */
	104
	105
[2463]	106	STATIC void tryexec(char , char , char *, int, int);
[2460]	107	STATIC void execinterp(char , char );
	108	STATIC void printentry(struct tblentry *, int);
	109	STATIC void clearcmdentry(int);
	110	STATIC struct tblentry cmdlookup(const char , int);
	111	STATIC void delete_cmd_entry(void);
[2463]	112	#ifdef PC_EXE_EXTS
	113	STATIC int stat_pc_exec_exts(char fullname, struct stat st, int has_ext);
	114	#endif
[2460]	115
	116
	117	extern char *const parsekwd[];
	118
	119	/*
	120	* Exec a program. Never returns. If you change this routine, you may
	121	* have to change the find_command routine as well.
	122	*/
	123
	124	void
	125	shellexec(char argv, char envp, const char *path, int idx, int vforked)
	126	{
	127	char *cmdname;
	128	int e;
[2463]	129	#ifdef PC_EXE_EXTS
	130	int has_ext = strlen(argv[0]) - 4;
	131	has_ext = has_ext > 0
	132	&& argv[0][has_ext] == '.'
	133	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
	134	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
	135	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
	136	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
	137	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
	138	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
	139	argv[0] + has_ext + 1)
	140	!= NULL;
	141	#else
	142	const int has_ext = 1;
	143	#endif
	144	TRACE(("shellexec: argv[0]=%s idx=%d\n", argv[0], idx));
[2460]	145	if (strchr(argv[0], '/') != NULL) {
[2463]	146	cmdname = stalloc(strlen(argv[0]) + 5);
	147	strcpy(cmdname, argv[0]);
	148	tryexec(cmdname, argv, envp, vforked, has_ext);
	149	TRACE(("shellexec: cmdname=%s\n", cmdname));
	150	stunalloc(cmdname);
[2460]	151	e = errno;
	152	} else {
	153	e = ENOENT;
	154	while ((cmdname = padvance(&path, argv[0])) != NULL) {
	155	if (--idx < 0 && pathopt == NULL) {
[2463]	156	tryexec(cmdname, argv, envp, vforked, has_ext);
[2460]	157	if (errno != ENOENT && errno != ENOTDIR)
	158	e = errno;
	159	}
	160	stunalloc(cmdname);
	161	}
	162	}
	163
	164	/* Map to POSIX errors */
	165	switch (e) {
	166	case EACCES:
	167	exerrno = 126;
	168	break;
	169	case ENOENT:
	170	exerrno = 127;
	171	break;
	172	default:
	173	exerrno = 2;
	174	break;
	175	}
[2463]	176	TRACE(("shellexec failed for '%s', errno %d, vforked %d, suppressint %d\n",
[2460]	177	argv[0], e, vforked, suppressint ));
	178	exerror(EXEXEC, "%s: %s", argv[0], errmsg(e, E_EXEC));
	179	/* NOTREACHED */
	180	}
	181
	182
	183	STATIC void
[2463]	184	tryexec(char cmd, char argv, char *envp, int vforked, int has_ext)
[2460]	185	{
	186	int e;
[2463]	187	#ifdef EXEC_HASH_BANG_SCRIPT
[2460]	188	char *p;
	189	#endif
[2463]	190	#ifdef PC_EXE_EXTS
	191	/* exploit the effect of stat_pc_exec_exts which adds the
	192	* correct extentions to the file.
	193	*/
	194	struct stat st;
	195	if (!has_ext)
	196	stat_pc_exec_exts(cmd, &st, 0);
	197	#endif
	198	#if defined __INNOTEK_LIBC__ && defined EXEC_HASH_BANG_SCRIPT
	199	__libc_Back_gfProcessHandleHashBangScripts = 0;
	200	#endif
[2460]	201
	202	#ifdef SYSV
	203	do {
	204	execve(cmd, argv, envp);
	205	} while (errno == EINTR);
	206	#else
	207	execve(cmd, argv, envp);
	208	#endif
	209	e = errno;
	210	if (e == ENOEXEC) {
	211	if (vforked) {
	212	/* We are currently vfork(2)ed, so raise an
	213	* exception, and evalcommand will try again
	214	* with a normal fork(2).
	215	*/
	216	exraise(EXSHELLPROC);
	217	}
	218	initshellproc();
	219	setinputfile(cmd, 0);
	220	commandname = arg0 = savestr(argv[0]);
[2463]	221	#ifdef EXEC_HASH_BANG_SCRIPT
[2460]	222	pgetc(); pungetc(); /* fill up input buffer */
	223	p = parsenextc;
	224	if (parsenleft > 2 && p[0] == '#' && p[1] == '!') {
	225	argv[0] = cmd;
	226	execinterp(argv, envp);
	227	}
	228	#endif
	229	setparam(argv + 1);
	230	exraise(EXSHELLPROC);
	231	}
[3271]	232	#ifdef __OS2__
	233	/* A lot of scripts references some core /bin/ programs, like for
	234	instance the bash testcases. So, to make life easier, we map
	235	a small set of these to @unixroot and or the PATH to simplify
	236	porting. */
	237	else if (!strncmp(cmd, "/bin/", sizeof("/bin/") - 1)) {
	238	char *name = cmd+ sizeof("/bin/") - 1;
	239	int search_path = 1;
	240	if (!strcmp(name, "sh")
	241	\|\| !strcmp(name, "sh.exe")
	242	\|\| !strcmp(name, "bash")
	243	\|\| !strcmp(name, "bash.exe")
	244	\|\| !strcmp(name, "ash")
	245	\|\| !strcmp(name, "ash.exe")
	246	\|\| !strcmp(name, "ls")
	247	\|\| !strcmp(name, "ls.exe")
	248	\|\| !strcmp(name, "cat")
	249	\|\| !strcmp(name, "cat.exe")
	250	\|\| !strcmp(name, "mkdir")
	251	\|\| !strcmp(name, "mkdir.exe")
	252	\|\| !strcmp(name, "expr")
	253	\|\| !strcmp(name, "expr.exe")
	254	\|\| !strcmp(name, "pwd")
	255	\|\| !strcmp(name, "pwd.exe")
	256	\|\| !strcmp(name, "tr")
	257	\|\| !strcmp(name, "tr.exe")
[3279]	258	\|\| !strcmp(name, "test")
	259	\|\| !strcmp(name, "test.exe")
	260	\|\| !strcmp(name, "echo")
	261	\|\| !strcmp(name, "echo.exe")
[3271]	262	\|\| (search_path = 0)
	263	\|\| !strcmp(name, "sort")
	264	\|\| !strcmp(name, "sort.exe")
	265	\|\| !strcmp(name, "cp")
	266	\|\| !strcmp(name, "cp.exe")
	267	\|\| !strcmp(name, "rm")
	268	\|\| !strcmp(name, "rm.exe")
	269	\|\| !strcmp(name, "unlink")
	270	\|\| !strcmp(name, "unlink.exe")
	271	\|\| !strcmp(name, "mv")
	272	\|\| !strcmp(name, "mv.exe")
	273	\|\| !strcmp(name, "rmdir")
	274	\|\| !strcmp(name, "rmdir.exe")
	275	) {
	276	char tmp[48];
	277	strcat(strcpy(tmp, "/@unixroot"), cmd);
	278	execve(tmp, argv, envp);
	279	if (search_path) {
	280	strcpy(tmp, name);
	281	if (!strchr(name, '.'))
	282	strcat(tmp, ".exe");
	283	execvpe(tmp, argv, envp);
	284	}
	285	}
	286	}
	287	#endif
[2460]	288	errno = e;
	289	}
	290
	291
[2463]	292	#ifdef EXEC_HASH_BANG_SCRIPT
[2460]	293	/*
	294	* Execute an interpreter introduced by "#!", for systems where this
	295	* feature has not been built into the kernel. If the interpreter is
	296	* the shell, return (effectively ignoring the "#!"). If the execution
	297	* of the interpreter fails, exit.
	298	*
	299	* This code peeks inside the input buffer in order to avoid actually
	300	* reading any input. It would benefit from a rewrite.
	301	*/
	302
	303	#define NEWARGS 5
	304
	305	STATIC void
	306	execinterp(char argv, char envp)
	307	{
	308	int n;
	309	char *inp;
	310	char *outp;
	311	char c;
	312	char *p;
	313	char **ap;
	314	char *newargs[NEWARGS];
	315	int i;
	316	char **ap2;
	317	char **new;
	318
	319	n = parsenleft - 2;
	320	inp = parsenextc + 2;
	321	ap = newargs;
	322	for (;;) {
	323	while (--n >= 0 && (inp == ' ' \|\| inp == '\t'))
	324	inp++;
	325	if (n < 0)
	326	goto bad;
	327	if ((c = *inp++) == '\n')
	328	break;
	329	if (ap == &newargs[NEWARGS])
	330	bad: error("Bad #! line");
	331	STARTSTACKSTR(outp);
	332	do {
	333	STPUTC(c, outp);
	334	} while (--n >= 0 && (c = *inp++) != ' ' && c != '\t' && c != '\n');
	335	STPUTC('\0', outp);
	336	n++, inp--;
	337	*ap++ = grabstackstr(outp);
	338	}
	339	if (ap == newargs + 1) { /* if no args, maybe no exec is needed */
	340	p = newargs[0];
	341	for (;;) {
	342	if (equal(p, "sh") \|\| equal(p, "ash")) {
[2463]	343	TRACE(("hash bang self\n"));
[2460]	344	return;
	345	}
	346	while (*p != '/') {
	347	if (*p == '\0')
	348	goto break2;
	349	p++;
	350	}
	351	p++;
	352	}
	353	break2:;
	354	}
	355	i = (char )ap - (char )newargs; /* size in bytes */
	356	if (i == 0)
	357	error("Bad #! line");
	358	for (ap2 = argv ; *ap2++ != NULL ; );
	359	new = ckmalloc(i + ((char )ap2 - (char )argv));
	360	ap = newargs, ap2 = new;
	361	while ((i -= sizeof (char **)) >= 0)
	362	ap2++ = ap++;
	363	ap = argv;
	364	while (ap2++ = ap++);
[2463]	365	TRACE(("hash bang '%s'\n", new[0]));
	366	shellexec(new, envp, pathval(), 0, 0);
[2460]	367	/* NOTREACHED */
	368	}
	369	#endif
	370
	371
	372
	373	/*
	374	* Do a path search. The variable path (passed by reference) should be
	375	* set to the start of the path before the first call; padvance will update
	376	* this value as it proceeds. Successive calls to padvance will return
	377	* the possible path expansions in sequence. If an option (indicated by
	378	* a percent sign) appears in the path entry then the global variable
	379	* pathopt will be set to point to it; otherwise pathopt will be set to
	380	* NULL.
	381	*/
	382
	383	const char *pathopt;
	384
	385	char *
	386	padvance(const char *path, const char name)
	387	{
	388	const char *p;
	389	char *q;
[3229]	390	#ifdef PC_SLASHES
[3164]	391	char *s;
	392	#endif
[2460]	393	const char *start;
	394	int len;
	395
	396	if (*path == NULL)
	397	return NULL;
	398	start = *path;
[2463]	399	#ifdef PC_PATH_SEP
	400	for (p = start ; p && p != ';' && *p != '%' ; p++);
	401	#else
[2460]	402	for (p = start ; p && p != ':' && *p != '%' ; p++);
[2463]	403	#endif
[2460]	404	len = p - start + strlen(name) + 2; /* "2" is for '/' and '\0' */
[2463]	405	#ifdef PC_EXE_EXTS
	406	len += 4; /* "4" is for .exe/.com/.cmd/.bat/.btm */
	407	#endif
[2460]	408	while (stackblocksize() < len)
	409	growstackblock();
[3229]	410	#ifdef PC_SLASHES
[3164]	411	s =
	412	#endif
[2460]	413	q = stackblock();
	414	if (p != start) {
	415	memcpy(q, start, p - start);
	416	q += p - start;
	417	*q++ = '/';
	418	}
	419	strcpy(q, name);
[3229]	420	#ifdef PC_SLASHES
[3164]	421	while ((s = strchr(s, '\\')) != NULL)
	422	*s++ = '/';
	423	#endif
[2460]	424	pathopt = NULL;
	425	if (*p == '%') {
	426	pathopt = ++p;
[2463]	427	#ifdef PC_PATH_SEP
	428	while (p && p != ';') p++;
	429	#else
[2460]	430	while (p && p != ':') p++;
[2463]	431	#endif
[2460]	432	}
[2463]	433	#ifdef PC_PATH_SEP
	434	if (*p == ';')
	435	#else
[2460]	436	if (*p == ':')
[2463]	437	#endif
[2460]	438	*path = p + 1;
	439	else
	440	*path = NULL;
	441	return stalloc(len);
	442	}
	443
	444
[2463]	445	#ifdef PC_EXE_EXTS
	446	STATIC int stat_pc_exec_exts(char fullname, struct stat st, int has_ext)
	447	{
	448	/* skip the SYSV crap */
	449	if (stat(fullname, st) >= 0)
	450	return 0;
	451	if (!has_ext && errno == ENOENT)
	452	{
	453	char *psz = strchr(fullname, '\0');
	454	memcpy(psz, ".exe", 5);
	455	if (stat(fullname, st) >= 0)
	456	return 0;
	457	if (errno != ENOENT && errno != ENOTDIR)
	458	return -1;
[2460]	459
[2463]	460	memcpy(psz, ".cmd", 5);
	461	if (stat(fullname, st) >= 0)
	462	return 0;
	463	if (errno != ENOENT && errno != ENOTDIR)
	464	return -1;
	465
	466	memcpy(psz, ".bat", 5);
	467	if (stat(fullname, st) >= 0)
	468	return 0;
	469	if (errno != ENOENT && errno != ENOTDIR)
	470	return -1;
	471
	472	memcpy(psz, ".com", 5);
	473	if (stat(fullname, st) >= 0)
	474	return 0;
	475	if (errno != ENOENT && errno != ENOTDIR)
	476	return -1;
	477
	478	memcpy(psz, ".btm", 5);
	479	if (stat(fullname, st) >= 0)
	480	return 0;
	481	*psz = '\0';
	482	}
	483	return -1;
	484	}
	485	#endif /* PC_EXE_EXTS */
	486
	487
	488
[2460]	489	/* Command hashing code */
	490
	491
	492	int
	493	hashcmd(int argc, char **argv)
	494	{
	495	struct tblentry **pp;
	496	struct tblentry *cmdp;
	497	int c;
	498	int verbose;
	499	struct cmdentry entry;
	500	char *name;
	501
	502	verbose = 0;
	503	while ((c = nextopt("rv")) != '\0') {
	504	if (c == 'r') {
	505	clearcmdentry(0);
	506	} else if (c == 'v') {
	507	verbose++;
	508	}
	509	}
	510	if (*argptr == NULL) {
	511	for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
	512	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
	513	if (verbose \|\| cmdp->cmdtype == CMDNORMAL)
	514	printentry(cmdp, verbose);
	515	}
	516	}
	517	return 0;
	518	}
	519	while ((name = *argptr) != NULL) {
	520	if ((cmdp = cmdlookup(name, 0)) != NULL
	521	&& (cmdp->cmdtype == CMDNORMAL
	522	\|\| (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
	523	delete_cmd_entry();
	524	find_command(name, &entry, DO_ERR, pathval());
	525	if (verbose) {
	526	if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
	527	cmdp = cmdlookup(name, 0);
	528	printentry(cmdp, verbose);
	529	}
[2463]	530	output_flushall();
[2460]	531	}
	532	argptr++;
	533	}
	534	return 0;
	535	}
	536
	537
	538	STATIC void
	539	printentry(struct tblentry *cmdp, int verbose)
	540	{
	541	int idx;
	542	const char *path;
	543	char *name;
	544
	545	switch (cmdp->cmdtype) {
	546	case CMDNORMAL:
	547	idx = cmdp->param.index;
	548	path = pathval();
	549	do {
	550	name = padvance(&path, cmdp->cmdname);
	551	stunalloc(name);
	552	} while (--idx >= 0);
	553	out1str(name);
	554	break;
	555	case CMDSPLBLTIN:
	556	out1fmt("special builtin %s", cmdp->cmdname);
	557	break;
	558	case CMDBUILTIN:
	559	out1fmt("builtin %s", cmdp->cmdname);
	560	break;
	561	case CMDFUNCTION:
	562	out1fmt("function %s", cmdp->cmdname);
	563	if (verbose) {
	564	struct procstat ps;
	565	INTOFF;
	566	commandtext(&ps, cmdp->param.func);
	567	INTON;
	568	out1str("() { ");
	569	out1str(ps.cmd);
	570	out1str("; }");
	571	}
	572	break;
	573	default:
	574	error("internal error: %s cmdtype %d", cmdp->cmdname, cmdp->cmdtype);
	575	}
	576	if (cmdp->rehash)
	577	out1c('*');
	578	out1c('\n');
	579	}
	580
	581
	582
	583	/*
	584	* Resolve a command name. If you change this routine, you may have to
	585	* change the shellexec routine as well.
	586	*/
	587
	588	void
	589	find_command(char name, struct cmdentry entry, int act, const char *path)
	590	{
	591	struct tblentry *cmdp, loc_cmd;
	592	int idx;
	593	int prev;
	594	char *fullname;
	595	struct stat statb;
	596	int e;
	597	int (bltin)(int,char *);
	598
[2463]	599	#ifdef PC_EXE_EXTS
	600	int has_ext = strlen(name) - 4;
	601	has_ext = has_ext > 0
	602	&& name[has_ext] == '.'
	603	/* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
	604	&& strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
	605	"cmd;" "Cmd;" "CMd;" "CMD;" "CmD;" "cMd;" "cMD;" "cmD;"
	606	"com;" "Com;" "COm;" "COM;" "CoM;" "cOm;" "cOM;" "coM;"
	607	"bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
	608	"btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
	609	name + has_ext + 1)
	610	!= NULL;
	611	#endif
	612
[2460]	613	/* If name contains a slash, don't use PATH or hash table */
	614	if (strchr(name, '/') != NULL) {
	615	if (act & DO_ABS) {
	616	while (stat(name, &statb) < 0) {
	617	#ifdef SYSV
	618	if (errno == EINTR)
	619	continue;
	620	#endif
	621	if (errno != ENOENT && errno != ENOTDIR)
	622	e = errno;
	623	entry->cmdtype = CMDUNKNOWN;
	624	entry->u.index = -1;
	625	return;
	626	}
	627	entry->cmdtype = CMDNORMAL;
	628	entry->u.index = -1;
	629	return;
	630	}
	631	entry->cmdtype = CMDNORMAL;
	632	entry->u.index = 0;
	633	return;
	634	}
	635
	636	if (path != pathval())
	637	act \|= DO_ALTPATH;
	638
	639	if (act & DO_ALTPATH && strstr(path, "%builtin") != NULL)
	640	act \|= DO_ALTBLTIN;
	641
	642	/* If name is in the table, check answer will be ok */
	643	if ((cmdp = cmdlookup(name, 0)) != NULL) {
	644	do {
	645	switch (cmdp->cmdtype) {
	646	case CMDNORMAL:
	647	if (act & DO_ALTPATH) {
	648	cmdp = NULL;
	649	continue;
	650	}
	651	break;
	652	case CMDFUNCTION:
	653	if (act & DO_NOFUNC) {
	654	cmdp = NULL;
	655	continue;
	656	}
	657	break;
	658	case CMDBUILTIN:
	659	if ((act & DO_ALTBLTIN) \|\| builtinloc >= 0) {
	660	cmdp = NULL;
	661	continue;
	662	}
	663	break;
	664	}
	665	/* if not invalidated by cd, we're done */
	666	if (cmdp->rehash == 0)
	667	goto success;
	668	} while (0);
	669	}
	670
	671	/* If %builtin not in path, check for builtin next */
	672	if ((act & DO_ALTPATH ? !(act & DO_ALTBLTIN) : builtinloc < 0) &&
	673	(bltin = find_builtin(name)) != 0)
	674	goto builtin_success;
	675
	676	/* We have to search path. */
	677	prev = -1; /* where to start */
	678	if (cmdp) { /* doing a rehash */
	679	if (cmdp->cmdtype == CMDBUILTIN)
	680	prev = builtinloc;
	681	else
	682	prev = cmdp->param.index;
	683	}
	684
	685	e = ENOENT;
	686	idx = -1;
	687	loop:
	688	while ((fullname = padvance(&path, name)) != NULL) {
	689	stunalloc(fullname);
	690	idx++;
	691	if (pathopt) {
	692	if (prefix("builtin", pathopt)) {
	693	if ((bltin = find_builtin(name)) == 0)
	694	goto loop;
	695	goto builtin_success;
	696	} else if (prefix("func", pathopt)) {
	697	/* handled below */
	698	} else {
	699	/* ignore unimplemented options */
	700	goto loop;
	701	}
	702	}
	703	/* if rehash, don't redo absolute path names */
	704	if (fullname[0] == '/' && idx <= prev) {
	705	if (idx < prev)
	706	goto loop;
	707	TRACE(("searchexec \"%s\": no change\n", name));
	708	goto success;
	709	}
[2463]	710	#ifdef PC_EXE_EXTS
	711	while (stat_pc_exec_exts(fullname, &statb, has_ext) < 0) {
	712	#else
[2460]	713	while (stat(fullname, &statb) < 0) {
[2463]	714	#endif
[2460]	715	#ifdef SYSV
	716	if (errno == EINTR)
	717	continue;
	718	#endif
	719	if (errno != ENOENT && errno != ENOTDIR)
	720	e = errno;
[2463]	721
[2460]	722	goto loop;
	723	}
	724	e = EACCES; /* if we fail, this will be the error */
	725	if (!S_ISREG(statb.st_mode))
	726	goto loop;
	727	if (pathopt) { /* this is a %func directory */
	728	if (act & DO_NOFUNC)
	729	goto loop;
	730	stalloc(strlen(fullname) + 1);
	731	readcmdfile(fullname);
	732	if ((cmdp = cmdlookup(name, 0)) == NULL \|\|
	733	cmdp->cmdtype != CMDFUNCTION)
	734	error("%s not defined in %s", name, fullname);
	735	stunalloc(fullname);
	736	goto success;
	737	}
	738	#ifdef notdef
	739	/* XXX this code stops root executing stuff, and is buggy
	740	if you need a group from the group list. */
	741	if (statb.st_uid == geteuid()) {
	742	if ((statb.st_mode & 0100) == 0)
	743	goto loop;
	744	} else if (statb.st_gid == getegid()) {
	745	if ((statb.st_mode & 010) == 0)
	746	goto loop;
	747	} else {
	748	if ((statb.st_mode & 01) == 0)
	749	goto loop;
	750	}
	751	#endif
	752	TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
	753	INTOFF;
	754	if (act & DO_ALTPATH) {
	755	stalloc(strlen(fullname) + 1);
	756	cmdp = &loc_cmd;
	757	} else
	758	cmdp = cmdlookup(name, 1);
	759	cmdp->cmdtype = CMDNORMAL;
	760	cmdp->param.index = idx;
	761	INTON;
	762	goto success;
	763	}
	764
	765	/* We failed. If there was an entry for this command, delete it */
	766	if (cmdp)
	767	delete_cmd_entry();
	768	if (act & DO_ERR)
	769	outfmt(out2, "%s: %s\n", name, errmsg(e, E_EXEC));
	770	entry->cmdtype = CMDUNKNOWN;
	771	return;
	772
	773	builtin_success:
	774	INTOFF;
	775	if (act & DO_ALTPATH)
	776	cmdp = &loc_cmd;
	777	else
	778	cmdp = cmdlookup(name, 1);
	779	if (cmdp->cmdtype == CMDFUNCTION)
	780	/* DO_NOFUNC must have been set */
	781	cmdp = &loc_cmd;
	782	cmdp->cmdtype = CMDBUILTIN;
	783	cmdp->param.bltin = bltin;
	784	INTON;
	785	success:
	786	cmdp->rehash = 0;
	787	entry->cmdtype = cmdp->cmdtype;
	788	entry->u = cmdp->param;
	789	}
	790
	791
	792
	793	/*
	794	* Search the table of builtin commands.
	795	*/
	796
	797	int
	798	(find_builtin(name))(int, char *)
	799	char *name;
	800	{
	801	const struct builtincmd *bp;
	802
	803	for (bp = builtincmd ; bp->name ; bp++) {
	804	if (bp->name == name && equal(bp->name, name))
	805	return bp->builtin;
	806	}
	807	return 0;
	808	}
	809
	810	int
	811	(find_splbltin(name))(int, char *)
	812	char *name;
	813	{
	814	const struct builtincmd *bp;
	815
	816	for (bp = splbltincmd ; bp->name ; bp++) {
	817	if (bp->name == name && equal(bp->name, name))
	818	return bp->builtin;
	819	}
	820	return 0;
	821	}
	822
	823	/*
	824	* At shell startup put special builtins into hash table.
	825	* ensures they are executed first (see posix).
	826	* We stop functions being added with the same name
	827	* (as they are impossible to call)
	828	*/
	829
	830	void
	831	hash_special_builtins(void)
	832	{
	833	const struct builtincmd *bp;
	834	struct tblentry *cmdp;
	835
	836	for (bp = splbltincmd ; bp->name ; bp++) {
	837	cmdp = cmdlookup(bp->name, 1);
	838	cmdp->cmdtype = CMDSPLBLTIN;
	839	cmdp->param.bltin = bp->builtin;
	840	}
	841	}
	842
	843
	844
	845	/*
	846	* Called when a cd is done. Marks all commands so the next time they
	847	* are executed they will be rehashed.
	848	*/
	849
	850	void
	851	hashcd(void)
	852	{
	853	struct tblentry **pp;
	854	struct tblentry *cmdp;
	855
	856	for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
	857	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
	858	if (cmdp->cmdtype == CMDNORMAL
	859	\|\| (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
	860	cmdp->rehash = 1;
	861	}
	862	}
	863	}
	864
	865
	866
	867	/*
	868	* Fix command hash table when PATH changed.
	869	* Called before PATH is changed. The argument is the new value of PATH;
	870	* pathval() still returns the old value at this point.
	871	* Called with interrupts off.
	872	*/
	873
	874	void
	875	changepath(const char *newval)
	876	{
	877	const char old, new;
	878	int idx;
	879	int firstchange;
	880	int bltin;
	881
	882	old = pathval();
	883	new = newval;
	884	firstchange = 9999; /* assume no change */
	885	idx = 0;
	886	bltin = -1;
	887	for (;;) {
	888	if (old != new) {
	889	firstchange = idx;
[2463]	890	#ifdef PC_PATH_SEP
	891	if ((old == '\0' && new == ';')
	892	\|\| (old == ';' && new == '\0'))
	893	#else
[2460]	894	if ((old == '\0' && new == ':')
	895	\|\| (old == ':' && new == '\0'))
[2463]	896	#endif
[2460]	897	firstchange++;
	898	old = new; /* ignore subsequent differences */
	899	}
	900	if (*new == '\0')
	901	break;
	902	if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
	903	bltin = idx;
[2463]	904	#ifdef PC_PATH_SEP
	905	if (*new == ';') {
	906	#else
[2460]	907	if (*new == ':') {
[2463]	908	#endif
[2460]	909	idx++;
	910	}
	911	new++, old++;
	912	}
	913	if (builtinloc < 0 && bltin >= 0)
	914	builtinloc = bltin; /* zap builtins */
	915	if (builtinloc >= 0 && bltin < 0)
	916	firstchange = 0;
	917	clearcmdentry(firstchange);
	918	builtinloc = bltin;
	919	}
	920
	921
	922	/*
	923	* Clear out command entries. The argument specifies the first entry in
	924	* PATH which has changed.
	925	*/
	926
	927	STATIC void
	928	clearcmdentry(int firstchange)
	929	{
	930	struct tblentry **tblp;
	931	struct tblentry **pp;
	932	struct tblentry *cmdp;
	933
	934	INTOFF;
	935	for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
	936	pp = tblp;
	937	while ((cmdp = *pp) != NULL) {
	938	if ((cmdp->cmdtype == CMDNORMAL &&
	939	cmdp->param.index >= firstchange)
	940	\|\| (cmdp->cmdtype == CMDBUILTIN &&
	941	builtinloc >= firstchange)) {
	942	*pp = cmdp->next;
	943	ckfree(cmdp);
	944	} else {
	945	pp = &cmdp->next;
	946	}
	947	}
	948	}
	949	INTON;
	950	}
	951
	952
	953	/*
	954	* Delete all functions.
	955	*/
	956
	957	#ifdef mkinit
	958	MKINIT void deletefuncs(void);
	959	MKINIT void hash_special_builtins(void);
	960
	961	INIT {
	962	hash_special_builtins();
	963	}
	964
	965	SHELLPROC {
	966	deletefuncs();
	967	}
	968	#endif
	969
	970	void
	971	deletefuncs(void)
	972	{
	973	struct tblentry **tblp;
	974	struct tblentry **pp;
	975	struct tblentry *cmdp;
	976
	977	INTOFF;
	978	for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
	979	pp = tblp;
	980	while ((cmdp = *pp) != NULL) {
	981	if (cmdp->cmdtype == CMDFUNCTION) {
	982	*pp = cmdp->next;
	983	freefunc(cmdp->param.func);
	984	ckfree(cmdp);
	985	} else {
	986	pp = &cmdp->next;
	987	}
	988	}
	989	}
	990	INTON;
	991	}
	992
	993
	994
	995	/*
	996	* Locate a command in the command hash table. If "add" is nonzero,
	997	* add the command to the table if it is not already present. The
	998	* variable "lastcmdentry" is set to point to the address of the link
	999	* pointing to the entry, so that delete_cmd_entry can delete the
	1000	* entry.
	1001	*/
	1002
	1003	struct tblentry **lastcmdentry;
	1004
	1005
	1006	STATIC struct tblentry *
	1007	cmdlookup(const char *name, int add)
	1008	{
	1009	int hashval;
	1010	const char *p;
	1011	struct tblentry *cmdp;
	1012	struct tblentry **pp;
	1013
	1014	p = name;
	1015	hashval = *p << 4;
	1016	while (*p)
	1017	hashval += *p++;
	1018	hashval &= 0x7FFF;
	1019	pp = &cmdtable[hashval % CMDTABLESIZE];
	1020	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
	1021	if (equal(cmdp->cmdname, name))
	1022	break;
	1023	pp = &cmdp->next;
	1024	}
	1025	if (add && cmdp == NULL) {
	1026	INTOFF;
	1027	cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
	1028	+ strlen(name) + 1);
	1029	cmdp->next = NULL;
	1030	cmdp->cmdtype = CMDUNKNOWN;
	1031	cmdp->rehash = 0;
	1032	strcpy(cmdp->cmdname, name);
	1033	INTON;
	1034	}
	1035	lastcmdentry = pp;
	1036	return cmdp;
	1037	}
	1038
	1039	/*
	1040	* Delete the command entry returned on the last lookup.
	1041	*/
	1042
	1043	STATIC void
	1044	delete_cmd_entry(void)
	1045	{
	1046	struct tblentry *cmdp;
	1047
	1048	INTOFF;
	1049	cmdp = *lastcmdentry;
	1050	*lastcmdentry = cmdp->next;
	1051	ckfree(cmdp);
	1052	INTON;
	1053	}
	1054
	1055
	1056
	1057	#ifdef notdef
	1058	void
	1059	getcmdentry(char name, struct cmdentry entry)
	1060	{
	1061	struct tblentry *cmdp = cmdlookup(name, 0);
	1062
	1063	if (cmdp) {
	1064	entry->u = cmdp->param;
	1065	entry->cmdtype = cmdp->cmdtype;
	1066	} else {
	1067	entry->cmdtype = CMDUNKNOWN;
	1068	entry->u.index = 0;
	1069	}
	1070	}
	1071	#endif
	1072
	1073
	1074	/*
	1075	* Add a new command entry, replacing any existing command entry for
	1076	* the same name - except special builtins.
	1077	*/
	1078
	1079	STATIC void
	1080	addcmdentry(char name, struct cmdentry entry)
	1081	{
	1082	struct tblentry *cmdp;
	1083
	1084	INTOFF;
	1085	cmdp = cmdlookup(name, 1);
	1086	if (cmdp->cmdtype != CMDSPLBLTIN) {
	1087	if (cmdp->cmdtype == CMDFUNCTION) {
	1088	freefunc(cmdp->param.func);
	1089	}
	1090	cmdp->cmdtype = entry->cmdtype;
	1091	cmdp->param = entry->u;
	1092	}
	1093	INTON;
	1094	}
	1095
	1096
	1097	/*
	1098	* Define a shell function.
	1099	*/
	1100
	1101	void
	1102	defun(char name, union node func)
	1103	{
	1104	struct cmdentry entry;
	1105
	1106	INTOFF;
	1107	entry.cmdtype = CMDFUNCTION;
	1108	entry.u.func = copyfunc(func);
	1109	addcmdentry(name, &entry);
	1110	INTON;
	1111	}
	1112
	1113
	1114	/*
	1115	* Delete a function if it exists.
	1116	*/
	1117
	1118	int
	1119	unsetfunc(char *name)
	1120	{
	1121	struct tblentry *cmdp;
	1122
	1123	if ((cmdp = cmdlookup(name, 0)) != NULL &&
	1124	cmdp->cmdtype == CMDFUNCTION) {
	1125	freefunc(cmdp->param.func);
	1126	delete_cmd_entry();
	1127	return (0);
	1128	}
	1129	return (1);
	1130	}
	1131
	1132	/*
	1133	* Locate and print what a word is...
	1134	* also used for 'command -[v\|V]'
	1135	*/
	1136
	1137	int
	1138	typecmd(int argc, char **argv)
	1139	{
	1140	struct cmdentry entry;
	1141	struct tblentry *cmdp;
	1142	char * const *pp;
	1143	struct alias *ap;
	1144	int err = 0;
	1145	char *arg;
	1146	int c;
	1147	int V_flag = 0;
	1148	int v_flag = 0;
	1149	int p_flag = 0;
	1150
	1151	while ((c = nextopt("vVp")) != 0) {
	1152	switch (c) {
	1153	case 'v': v_flag = 1; break;
	1154	case 'V': V_flag = 1; break;
	1155	case 'p': p_flag = 1; break;
	1156	}
	1157	}
	1158
	1159	if (p_flag && (v_flag \|\| V_flag))
	1160	error("cannot specify -p with -v or -V");
	1161
	1162	while ((arg = *argptr++)) {
	1163	if (!v_flag)
	1164	out1str(arg);
	1165	/* First look at the keywords */
	1166	for (pp = parsekwd; *pp; pp++)
	1167	if (*pp == arg && equal(*pp, arg))
	1168	break;
	1169
	1170	if (*pp) {
	1171	if (v_flag)
	1172	err = 1;
	1173	else
	1174	out1str(" is a shell keyword\n");
	1175	continue;
	1176	}
	1177
	1178	/* Then look at the aliases */
	1179	if ((ap = lookupalias(arg, 1)) != NULL) {
	1180	if (!v_flag)
	1181	out1fmt(" is an alias for \n");
	1182	out1fmt("%s\n", ap->val);
	1183	continue;
	1184	}
	1185
	1186	/* Then check if it is a tracked alias */
	1187	if ((cmdp = cmdlookup(arg, 0)) != NULL) {
	1188	entry.cmdtype = cmdp->cmdtype;
	1189	entry.u = cmdp->param;
	1190	} else {
	1191	/* Finally use brute force */
	1192	find_command(arg, &entry, DO_ABS, pathval());
	1193	}
	1194
	1195	switch (entry.cmdtype) {
	1196	case CMDNORMAL: {
	1197	if (strchr(arg, '/') == NULL) {
	1198	const char *path = pathval();
	1199	char *name;
	1200	int j = entry.u.index;
	1201	do {
	1202	name = padvance(&path, arg);
	1203	stunalloc(name);
	1204	} while (--j >= 0);
	1205	if (!v_flag)
	1206	out1fmt(" is%s ",
	1207	cmdp ? " a tracked alias for" : "");
	1208	out1fmt("%s\n", name);
	1209	} else {
	1210	if (access(arg, X_OK) == 0) {
	1211	if (!v_flag)
	1212	out1fmt(" is ");
	1213	out1fmt("%s\n", arg);
	1214	} else {
	1215	if (!v_flag)
	1216	out1fmt(": %s\n",
	1217	strerror(errno));
	1218	else
	1219	err = 126;
	1220	}
	1221	}
	1222	break;
	1223	}
	1224	case CMDFUNCTION:
	1225	if (!v_flag)
	1226	out1str(" is a shell function\n");
	1227	else
	1228	out1fmt("%s\n", arg);
	1229	break;
	1230
	1231	case CMDBUILTIN:
	1232	if (!v_flag)
	1233	out1str(" is a shell builtin\n");
	1234	else
	1235	out1fmt("%s\n", arg);
	1236	break;
	1237
	1238	case CMDSPLBLTIN:
	1239	if (!v_flag)
	1240	out1str(" is a special shell builtin\n");
	1241	else
	1242	out1fmt("%s\n", arg);
	1243	break;
	1244
	1245	default:
	1246	if (!v_flag)
	1247	out1str(": not found\n");
	1248	err = 127;
	1249	break;
	1250	}
	1251	}
	1252	return err;
	1253	}

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source: trunk/ash/exec.c@ 3466

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