var.c@ 2637

Last change on this file since 2637 was 2637, checked in by bird, 12 years ago
kash: Simplified that 'Path' hack on Windows.
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File size: 20.2 KB

Line
1	/* $NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami 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[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
38	#else
39	__RCSID("$NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami Exp $");
40	#endif /* not lint */
41	#endif
42
43	#include <stddef.h>
44	#include <stdlib.h>
45	#include <string.h>
46
47	#ifdef PC_OS2_LIBPATHS
48	#define INCL_BASE
49	#include <os2.h>
50
51	#ifndef LIBPATHSTRICT
52	#define LIBPATHSTRICT 3
53	#endif
54
55	extern APIRET
56	#ifdef APIENTRY
57	APIENTRY
58	#endif
59	DosQueryHeaderInfo(HMODULE hmod, ULONG ulIndex, PVOID pvBuffer, ULONG cbBuffer, ULONG ulSubFunction);
60	#define QHINF_EXEINFO 1 /* NE exeinfo. */
61	#define QHINF_READRSRCTBL 2 /* Reads from the resource table. */
62	#define QHINF_READFILE 3 /* Reads from the executable file. */
63	#define QHINF_LIBPATHLENGTH 4 /* Gets the libpath length. */
64	#define QHINF_LIBPATH 5 /* Gets the entire libpath. */
65	#define QHINF_FIXENTRY 6 /* NE only */
66	#define QHINF_STE 7 /* NE only */
67	#define QHINF_MAPSEL 8 /* NE only */
68
69	#endif
70
71
72
73	/*
74	* Shell variables.
75	*/
76
77	#include "shell.h"
78	#include "output.h"
79	#include "expand.h"
80	#include "nodes.h" /* for other headers */
81	#include "eval.h" /* defines cmdenviron */
82	#include "exec.h"
83	#include "syntax.h"
84	#include "options.h"
85	#include "mail.h"
86	#include "var.h"
87	#include "memalloc.h"
88	#include "error.h"
89	#include "mystring.h"
90	#include "parser.h"
91	#include "show.h"
92	#ifndef SMALL
93	# include "myhistedit.h"
94	#endif
95	#include "shinstance.h"
96
97	//#ifdef SMALL
98	//#define VTABSIZE 39
99	//#else
100	//#define VTABSIZE 517
101	//#endif
102
103
104	struct varinit {
105	unsigned var_off;
106	int flags;
107	const char *text;
108	void (func)(shinstance , const char *);
109	};
110
111
112	//#if ATTY
113	//struct var vatty;
114	//#endif
115	//#ifndef SMALL
116	//struct var vhistsize;
117	//struct var vterm;
118	//#endif
119	//struct var vifs;
120	//struct var vmail;
121	//struct var vmpath;
122	//struct var vpath;
123	//#ifdef _MSC_VER
124	//struct var vpath2;
125	//#endif
126	//struct var vps1;
127	//struct var vps2;
128	//struct var vps4;
129	//struct var vvers; - unused
130	//struct var voptind;
131
132	#ifdef PC_OS2_LIBPATHS
133	//static struct var libpath_vars[4];
134	static const char * const libpath_envs[4] = {"LIBPATH=", "BEGINLIBPATH=", "ENDLIBPATH=", "LIBPATHSTRICT="};
135	#endif
136
137	const struct varinit varinit[] = {
138	#if ATTY
139	{ offsetof(shinstance, vatty), VSTRFIXED\|VTEXTFIXED\|VUNSET, "ATTY=",
140	NULL },
141	#endif
142	#ifndef SMALL
143	{ offsetof(shinstance, vhistsize), VSTRFIXED\|VTEXTFIXED\|VUNSET, "HISTSIZE=",
144	sethistsize },
145	#endif
146	{ offsetof(shinstance, vifs), VSTRFIXED\|VTEXTFIXED, "IFS= \t\n",
147	NULL },
148	{ offsetof(shinstance, vmail), VSTRFIXED\|VTEXTFIXED\|VUNSET, "MAIL=",
149	NULL },
150	{ offsetof(shinstance, vmpath), VSTRFIXED\|VTEXTFIXED\|VUNSET, "MAILPATH=",
151	NULL },
152	{ offsetof(shinstance, vpath), VSTRFIXED\|VTEXTFIXED, "PATH=" _PATH_DEFPATH,
153	changepath },
154	/*
155	* vps1 depends on uid
156	*/
157	{ offsetof(shinstance, vps2), VSTRFIXED\|VTEXTFIXED, "PS2=> ",
158	NULL },
159	{ offsetof(shinstance, vps4), VSTRFIXED\|VTEXTFIXED, "PS4=+ ",
160	NULL },
161	#ifndef SMALL
162	{ offsetof(shinstance, vterm), VSTRFIXED\|VTEXTFIXED\|VUNSET, "TERM=",
163	setterm },
164	#endif
165	{ offsetof(shinstance, voptind), VSTRFIXED\|VTEXTFIXED\|VNOFUNC, "OPTIND=1",
166	getoptsreset },
167	{ 0, 0, NULL,
168	NULL }
169	};
170
171	//struct var *vartab[VTABSIZE];
172
173	STATIC int strequal(const char , const char );
174	STATIC struct var find_var(shinstance , const char , struct var *, int );
175
176	/*
177	* Initialize the varable symbol tables and import the environment
178	*/
179
180	#ifdef mkinit
181	INCLUDE "var.h"
182
183	INIT {
184	char **envp;
185
186	initvar(psh);
187	for (envp = sh_environ(psh) ; *envp ; envp++) {
188	if (strchr(*envp, '=')) {
189	setvareq(psh, *envp, VEXPORT\|VTEXTFIXED);
190	}
191	}
192	}
193	#endif
194
195
196	/*
197	* This routine initializes the builtin variables. It is called when the
198	* shell is initialized and again when a shell procedure is spawned.
199	*/
200
201	void
202	initvar(shinstance *psh)
203	{
204	const struct varinit *ip;
205	struct var *vp;
206	struct var **vpp;
207	#ifdef PC_OS2_LIBPATHS
208	char *psz = ckmalloc(psh, 2048);
209	int rc;
210	int i;
211
212	for (i = 0; i < 4; i++)
213	{
214	psh->libpath_vars[i].flags = VSTRFIXED \| VOS2LIBPATH;
215	psh->libpath_vars[i].func = NULL;
216
217	if (i > 0)
218	{
219	psz[0] = psz[1] = psz[2] = psz[3] = '\0';
220	rc = DosQueryExtLIBPATH(psz, i);
221	}
222	else
223	{
224	rc = DosQueryHeaderInfo(NULLHANDLE, 0, psz, 2048, QHINF_LIBPATH);
225	psh->libpath_vars[i].flags \|= VREADONLY;
226	}
227	if (!rc && *psz)
228	{
229	int cch1 = strlen(libpath_envs[i]);
230	int cch2 = strlen(psz) + 1;
231	psh->libpath_vars[i].text = ckmalloc(psh, cch1 + cch2);
232	memcpy(psh->libpath_vars[i].text, libpath_envs[i], cch1);
233	memcpy(psh->libpath_vars[i].text + cch1, psz, cch2);
234	}
235	else
236	{
237	psh->libpath_vars[i].flags \|= VUNSET \| VTEXTFIXED;
238	psh->libpath_vars[i].text = (char*)libpath_envs[i];
239	}
240	if (find_var(psh, psh->libpath_vars[i].text, &vpp, &psh->libpath_vars[i].name_len) != NULL)
241	continue;
242	psh->libpath_vars[i].next = *vpp;
243	*vpp = &psh->libpath_vars[i];
244	}
245	ckfree(psh, psz);
246	#endif
247
248	for (ip = varinit; ip->text; ip++) {
249	vp = (struct var )((char )psh + ip->var_off);
250	if (find_var(psh, ip->text, &vpp, &vp->name_len) != NULL)
251	continue;
252	vp->next = *vpp;
253	*vpp = vp;
254	vp->text = sh_strdup(psh, ip->text);
255	vp->flags = ip->flags;
256	vp->func = ip->func;
257	}
258	/*
259	* PS1 depends on uid
260	*/
261	if (find_var(psh, "PS1", &vpp, &psh->vps1.name_len) == NULL) {
262	psh->vps1.next = *vpp;
263	*vpp = &psh->vps1;
264	#ifdef KBUILD_VERSION_MAJOR
265	psh->vps1.text = sh_strdup(psh, sh_geteuid(psh) ? "PS1=kash$ " : "PS1=kash# ");
266	#else
267	psh->vps1.text = sh_strdup(psh, sh_geteuid(psh) ? "PS1=$ " : "PS1=# ");
268	#endif
269	psh->vps1.flags = VSTRFIXED\|VTEXTFIXED;
270	}
271	}
272
273	/*
274	* Safe version of setvar, returns 1 on success 0 on failure.
275	*/
276
277	int
278	setvarsafe(shinstance psh, const char name, const char *val, int flags)
279	{
280	struct jmploc jmploc;
281	struct jmploc *volatile savehandler = psh->handler;
282	int err = 0;
283	#ifdef __GNUC__
284	(void) &err;
285	#endif
286
287	if (setjmp(jmploc.loc))
288	err = 1;
289	else {
290	psh->handler = &jmploc;
291	setvar(psh, name, val, flags);
292	}
293	psh->handler = savehandler;
294	return err;
295	}
296
297	/*
298	* Set the value of a variable. The flags argument is ored with the
299	* flags of the variable. If val is NULL, the variable is unset.
300	*/
301
302	void
303	setvar(shinstance psh, const char name, const char *val, int flags)
304	{
305	const char *p;
306	const char *q;
307	char *d;
308	size_t len;
309	int namelen;
310	char *nameeq;
311	int isbad;
312
313	isbad = 0;
314	p = name;
315	if (! is_name(*p))
316	isbad = 1;
317	p++;
318	for (;;) {
319	if (! is_in_name(*p)) {
320	if (p == '\0' \|\| p == '=')
321	break;
322	isbad = 1;
323	}
324	p++;
325	}
326	namelen = (int)(p - name);
327	if (isbad)
328	error(psh, "%.*s: bad variable name", namelen, name);
329	len = namelen + 2; /* 2 is space for '=' and '\0' */
330	if (val == NULL) {
331	flags \|= VUNSET;
332	} else {
333	len += strlen(val);
334	}
335	d = nameeq = ckmalloc(psh, len);
336	q = name;
337	while (--namelen >= 0)
338	d++ = q++;
339	*d++ = '=';
340	*d = '\0';
341	if (val)
342	scopy(val, d);
343	setvareq(psh, nameeq, flags);
344	}
345
346
347
348	/*
349	* Same as setvar except that the variable and value are passed in
350	* the first argument as name=value. Since the first argument will
351	* be actually stored in the table, it should not be a string that
352	* will go away.
353	*/
354
355	void
356	setvareq(shinstance psh, char s, int flags)
357	{
358	struct var vp, *vpp;
359	int nlen;
360
361	fprintf(stderr, "debug: setvareq '%s'\n", s);
362	#if defined(_MSC_VER) \|\| defined(_WIN32)
363	/* On Windows PATH is often spelled 'Path', correct this here. */
364	if ( s[0] == 'P'
365	&& s[1] == 'a'
366	&& s[2] == 't'
367	&& s[3] == 'h'
368	&& (s[4] == '\0' \|\| s[4] == '=') ) {
369	s[1] = 'A';
370	s[2] = 'T';
371	s[3] = 'H';
372	fprintf(stderr, "debug: setvareq '%s' FIXED\n", s);
373	}
374	#endif
375
376	if (aflag(psh))
377	flags \|= VEXPORT;
378	vp = find_var(psh, s, &vpp, &nlen);
379	if (vp != NULL) {
380	if (vp->flags & VREADONLY)
381	error(psh, "%.*s: is read only", vp->name_len, s);
382	if (flags & VNOSET)
383	return;
384	INTOFF;
385
386	if (vp->func && (flags & VNOFUNC) == 0)
387	(*vp->func)(psh, s + vp->name_len + 1);
388
389	if ((vp->flags & (VTEXTFIXED\|VSTACK)) == 0)
390	ckfree(psh, vp->text);
391
392	vp->flags &= ~(VTEXTFIXED\|VSTACK\|VUNSET);
393	vp->flags \|= flags & ~VNOFUNC;
394	vp->text = s;
395	#ifdef PC_OS2_LIBPATHS
396	if ((vp->flags & VOS2LIBPATH) && (vp->flags & VEXPORT))
397	vp->flags &= ~VEXPORT;
398	#endif
399
400	/*
401	* We could roll this to a function, to handle it as
402	* a regular variable function callback, but why bother?
403	*/
404	if (vp == &psh->vmpath \|\| (vp == &psh->vmail && ! mpathset(psh)))
405	chkmail(psh, 1);
406	INTON;
407	return;
408	}
409	/* not found */
410	if (flags & VNOSET)
411	return;
412
413	vp = ckmalloc(psh, sizeof (*vp));
414	vp->flags = flags & ~VNOFUNC;
415	vp->text = s;
416	vp->name_len = nlen;
417	vp->next = *vpp;
418	vp->func = NULL;
419	*vpp = vp;
420	}
421
422
423
424	/*
425	* Process a linked list of variable assignments.
426	*/
427
428	void
429	listsetvar(shinstance psh, struct strlist list, int flags)
430	{
431	struct strlist *lp;
432
433	INTOFF;
434	for (lp = list ; lp ; lp = lp->next) {
435	setvareq(psh, savestr(psh, lp->text), flags);
436	}
437	INTON;
438	}
439
440	void
441	listmklocal(shinstance psh, struct strlist list, int flags)
442	{
443	struct strlist *lp;
444
445	for (lp = list ; lp ; lp = lp->next)
446	mklocal(psh, lp->text, flags);
447	}
448
449
450	/*
451	* Find the value of a variable. Returns NULL if not set.
452	*/
453
454	char *
455	lookupvar(shinstance psh, const char name)
456	{
457	struct var *v;
458
459	v = find_var(psh, name, NULL, NULL);
460	if (v == NULL \|\| v->flags & VUNSET)
461	return NULL;
462	return v->text + v->name_len + 1;
463	}
464
465
466
467	/*
468	* Search the environment of a builtin command. If the second argument
469	* is nonzero, return the value of a variable even if it hasn't been
470	* exported.
471	*/
472
473	char *
474	bltinlookup(shinstance psh, const char name, int doall)
475	{
476	struct strlist *sp;
477	struct var *v;
478
479	for (sp = psh->cmdenviron ; sp ; sp = sp->next) {
480	if (strequal(sp->text, name))
481	return strchr(sp->text, '=') + 1;
482	}
483
484	v = find_var(psh, name, NULL, NULL);
485
486	if (v == NULL \|\| v->flags & VUNSET \|\| (!doall && !(v->flags & VEXPORT)))
487	return NULL;
488	return v->text + v->name_len + 1;
489	}
490
491
492
493	/*
494	* Generate a list of exported variables. This routine is used to construct
495	* the third argument to execve when executing a program.
496	*/
497
498	char **
499	environment(shinstance *psh)
500	{
501	int nenv;
502	struct var **vpp;
503	struct var *vp;
504	char **env;
505	char **ep;
506
507	nenv = 0;
508	for (vpp = psh->vartab ; vpp < psh->vartab + VTABSIZE ; vpp++) {
509	for (vp = *vpp ; vp ; vp = vp->next)
510	if (vp->flags & VEXPORT)
511	nenv++;
512	}
513	ep = env = stalloc(psh, (nenv + 1) * sizeof *env);
514	for (vpp = psh->vartab ; vpp < psh->vartab + VTABSIZE ; vpp++) {
515	for (vp = *vpp ; vp ; vp = vp->next)
516	if (vp->flags & VEXPORT)
517	*ep++ = vp->text;
518	}
519	*ep = NULL;
520
521	#ifdef PC_OS2_LIBPATHS
522	/*
523	* Set the libpaths now as this is exec() time.
524	*/
525	for (nenv = 0; nenv < 3; nenv++)
526	DosSetExtLIBPATH(strchr(psh->libpath_vars[nenv].text, '=') + 1, nenv);
527	#endif
528
529	return env;
530	}
531
532
533	/*
534	* Called when a shell procedure is invoked to clear out nonexported
535	* variables. It is also necessary to reallocate variables of with
536	* VSTACK set since these are currently allocated on the stack.
537	*/
538
539	#ifdef mkinit
540	void shprocvar(shinstance *psh);
541
542	SHELLPROC {
543	shprocvar(psh);
544	}
545	#endif
546
547	void
548	shprocvar(shinstance *psh)
549	{
550	struct var **vpp;
551	struct var vp, *prev;
552
553	for (vpp = psh->vartab ; vpp < psh->vartab + VTABSIZE ; vpp++) {
554	for (prev = vpp ; (vp = *prev) != NULL ; ) {
555	if ((vp->flags & VEXPORT) == 0) {
556	*prev = vp->next;
557	if ((vp->flags & VTEXTFIXED) == 0)
558	ckfree(psh, vp->text);
559	if ((vp->flags & VSTRFIXED) == 0)
560	ckfree(psh, vp);
561	} else {
562	if (vp->flags & VSTACK) {
563	vp->text = savestr(psh, vp->text);
564	vp->flags &=~ VSTACK;
565	}
566	prev = &vp->next;
567	}
568	}
569	}
570	initvar(psh);
571	}
572
573
574
575	/*
576	* Command to list all variables which are set. Currently this command
577	* is invoked from the set command when the set command is called without
578	* any variables.
579	*/
580
581	void
582	print_quoted(shinstance psh, const char p)
583	{
584	const char *q;
585
586	if (strcspn(p, "\|&;<>()$`\\\"' \t\n*?[]#~=%") == strlen(p)) {
587	out1fmt(psh, "%s", p);
588	return;
589	}
590	while (*p) {
591	if (*p == '\'') {
592	out1fmt(psh, "\\'");
593	p++;
594	continue;
595	}
596	q = strchr(p, '\'');
597	if (!q) {
598	out1fmt(psh, "'%s'", p );
599	return;
600	}
601	out1fmt(psh, "'%.*s'", (int)(q - p), p );
602	p = q;
603	}
604	}
605
606	static int
607	sort_var(const void v_v1, const void v_v2)
608	{
609	const struct var * const *v1 = v_v1;
610	const struct var * const *v2 = v_v2;
611
612	/* XXX Will anyone notice we include the '=' of the shorter name? */
613	return strcoll((v1)->text, (v2)->text);
614	}
615
616	/*
617	* POSIX requires that 'set' (but not export or readonly) output the
618	* variables in lexicographic order - by the locale's collating order (sigh).
619	* Maybe we could keep them in an ordered balanced binary tree
620	* instead of hashed lists.
621	* For now just roll 'em through qsort for printing...
622	*/
623
624	int
625	showvars(shinstance psh, const char name, int flag, int show_value)
626	{
627	struct var **vpp;
628	struct var *vp;
629	const char *p;
630
631	static struct var *list; / static in case we are interrupted */
632	static int list_len;
633	int count = 0;
634
635	if (!list) {
636	list_len = 32;
637	list = ckmalloc(psh, list_len * sizeof(*list));
638	}
639
640	for (vpp = psh->vartab ; vpp < psh->vartab + VTABSIZE ; vpp++) {
641	for (vp = *vpp ; vp ; vp = vp->next) {
642	if (flag && !(vp->flags & flag))
643	continue;
644	if (vp->flags & VUNSET && !(show_value & 2))
645	continue;
646	if (count >= list_len) {
647	list = ckrealloc(psh, list,
648	(list_len << 1) * sizeof(*list));
649	list_len <<= 1;
650	}
651	list[count++] = vp;
652	}
653	}
654
655	qsort(list, count, sizeof(*list), sort_var);
656
657	for (vpp = list; count--; vpp++) {
658	vp = *vpp;
659	if (name)
660	out1fmt(psh, "%s ", name);
661	for (p = vp->text ; *p != '=' ; p++)
662	out1c(psh, *p);
663	if (!(vp->flags & VUNSET) && show_value) {
664	out1fmt(psh, "=");
665	print_quoted(psh, ++p);
666	}
667	out1c(psh, '\n');
668	}
669	return 0;
670	}
671
672
673
674	/*
675	* The export and readonly commands.
676	*/
677
678	int
679	exportcmd(shinstance psh, int argc, char *argv)
680	{
681	struct var *vp;
682	char *name;
683	const char *p;
684	int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
685	int pflag;
686
687	pflag = nextopt(psh, "p") == 'p' ? 3 : 0;
688	if (argc <= 1 \|\| pflag) {
689	showvars(psh, pflag ? argv[0] : 0, flag, pflag );
690	return 0;
691	}
692
693	while ((name = *psh->argptr++) != NULL) {
694	if ((p = strchr(name, '=')) != NULL) {
695	p++;
696	} else {
697	vp = find_var(psh, name, NULL, NULL);
698	if (vp != NULL) {
699	vp->flags \|= flag;
700	continue;
701	}
702	}
703	setvar(psh, name, p, flag);
704	}
705	return 0;
706	}
707
708
709	/*
710	* The "local" command.
711	*/
712
713	int
714	localcmd(shinstance psh, int argc, char *argv)
715	{
716	char *name;
717
718	if (! in_function(psh))
719	error(psh, "Not in a function");
720	while ((name = *psh->argptr++) != NULL) {
721	mklocal(psh, name, 0);
722	}
723	return 0;
724	}
725
726
727	/*
728	* Make a variable a local variable. When a variable is made local, it's
729	* value and flags are saved in a localvar structure. The saved values
730	* will be restored when the shell function returns. We handle the name
731	* "-" as a special case.
732	*/
733
734	void
735	mklocal(shinstance psh, const char name, int flags)
736	{
737	struct localvar *lvp;
738	struct var **vpp;
739	struct var *vp;
740
741	INTOFF;
742	lvp = ckmalloc(psh, sizeof (struct localvar));
743	if (name[0] == '-' && name[1] == '\0') {
744	char *p;
745	p = ckmalloc(psh, sizeof_optlist);
746	lvp->text = memcpy(p, psh->optlist, sizeof_optlist);
747	vp = NULL;
748	} else {
749	vp = find_var(psh, name, &vpp, NULL);
750	if (vp == NULL) {
751	if (strchr(name, '='))
752	setvareq(psh, savestr(psh, name), VSTRFIXED\|flags);
753	else
754	setvar(psh, name, NULL, VSTRFIXED\|flags);
755	vp = vpp; / the new variable */
756	lvp->text = NULL;
757	lvp->flags = VUNSET;
758	} else {
759	lvp->text = vp->text;
760	lvp->flags = vp->flags;
761	vp->flags \|= VSTRFIXED\|VTEXTFIXED;
762	if (name[vp->name_len] == '=')
763	setvareq(psh, savestr(psh, name), flags);
764	}
765	}
766	lvp->vp = vp;
767	lvp->next = psh->localvars;
768	psh->localvars = lvp;
769	INTON;
770	}
771
772
773	/*
774	* Called after a function returns.
775	*/
776
777	void
778	poplocalvars(shinstance *psh)
779	{
780	struct localvar *lvp;
781	struct var *vp;
782
783	while ((lvp = psh->localvars) != NULL) {
784	psh->localvars = lvp->next;
785	vp = lvp->vp;
786	TRACE((psh, "poplocalvar %s", vp ? vp->text : "-"));
787	if (vp == NULL) { /* $- saved */
788	memcpy(psh->optlist, lvp->text, sizeof_optlist);
789	ckfree(psh, lvp->text);
790	} else if ((lvp->flags & (VUNSET\|VSTRFIXED)) == VUNSET) {
791	(void)unsetvar(psh, vp->text, 0);
792	} else {
793	if (vp->func && (vp->flags & VNOFUNC) == 0)
794	(*vp->func)(psh, lvp->text + vp->name_len + 1);
795	if ((vp->flags & VTEXTFIXED) == 0)
796	ckfree(psh, vp->text);
797	vp->flags = lvp->flags;
798	vp->text = lvp->text;
799	}
800	ckfree(psh, lvp);
801	}
802	}
803
804
805	int
806	setvarcmd(shinstance psh, int argc, char *argv)
807	{
808	if (argc <= 2)
809	return unsetcmd(psh, argc, argv);
810	else if (argc == 3)
811	setvar(psh, argv[1], argv[2], 0);
812	else
813	error(psh, "List assignment not implemented");
814	return 0;
815	}
816
817
818	/*
819	* The unset builtin command. We unset the function before we unset the
820	* variable to allow a function to be unset when there is a readonly variable
821	* with the same name.
822	*/
823
824	int
825	unsetcmd(shinstance psh, int argc, char *argv)
826	{
827	char **ap;
828	int i;
829	int flg_func = 0;
830	int flg_var = 0;
831	int ret = 0;
832
833	while ((i = nextopt(psh, "evf")) != '\0') {
834	if (i == 'f')
835	flg_func = 1;
836	else
837	flg_var = i;
838	}
839	if (flg_func == 0 && flg_var == 0)
840	flg_var = 1;
841
842	for (ap = psh->argptr; *ap ; ap++) {
843	if (flg_func)
844	ret \|= unsetfunc(psh, *ap);
845	if (flg_var)
846	ret \|= unsetvar(psh, *ap, flg_var == 'e');
847	}
848	return ret;
849	}
850
851
852	/*
853	* Unset the specified variable.
854	*/
855
856	int
857	unsetvar(shinstance psh, const char s, int unexport)
858	{
859	struct var **vpp;
860	struct var *vp;
861
862	vp = find_var(psh, s, &vpp, NULL);
863	if (vp == NULL)
864	return 1;
865
866	if (vp->flags & VREADONLY)
867	return (1);
868
869	INTOFF;
870	if (unexport) {
871	vp->flags &= ~VEXPORT;
872	} else {
873	if (vp->text[vp->name_len + 1] != '\0')
874	setvar(psh, s, nullstr, 0);
875	vp->flags &= ~VEXPORT;
876	vp->flags \|= VUNSET;
877	if ((vp->flags & VSTRFIXED) == 0) {
878	if ((vp->flags & VTEXTFIXED) == 0)
879	ckfree(psh, vp->text);
880	*vpp = vp->next;
881	ckfree(psh, vp);
882	}
883	}
884	INTON;
885	return 0;
886	}
887
888
889	/*
890	* Returns true if the two strings specify the same varable. The first
891	* variable name is terminated by '='; the second may be terminated by
892	* either '=' or '\0'.
893	*/
894
895	STATIC int
896	strequal(const char p, const char q)
897	{
898	while (p == q++) {
899	if (*p++ == '=')
900	return 1;
901	}
902	if (p == '=' && (q - 1) == '\0')
903	return 1;
904	return 0;
905	}
906
907	/*
908	* Search for a variable.
909	* 'name' may be terminated by '=' or a NUL.
910	* vppp is set to the pointer to vp, or the list head if vp isn't found
911	* lenp is set to the number of charactets in 'name'
912	*/
913
914	STATIC struct var *
915	find_var(shinstance psh, const char name, struct var **vppp, int lenp)
916	{
917	unsigned int hashval;
918	int len;
919	struct var vp, *vpp;
920	const char *p = name;
921
922	hashval = 0;
923	while (p && p != '=')
924	hashval = 2 * hashval + (unsigned char)*p++;
925	len = (int)(p - name);
926
927	if (lenp)
928	*lenp = len;
929	vpp = &psh->vartab[hashval % VTABSIZE];
930	if (vppp)
931	*vppp = vpp;
932
933	for (vp = vpp ; vp ; vpp = &vp->next, vp = vpp) {
934	if (vp->name_len != len)
935	continue;
936	if (memcmp(vp->text, name, len) != 0)
937	continue;
938	if (vppp)
939	*vppp = vpp;
940	return vp;
941	}
942	return NULL;
943	}

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source: kBuild/trunk/src/kash/var.c@ 2637

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