xref: /openbsd-src/usr.bin/make/arch.c (revision ff0e7be1ebbcc809ea8ad2b6dafe215824da9e46)
1 /*	$OpenBSD: arch.c,v 1.93 2023/02/17 17:59:36 miod Exp $ */
2 /*	$NetBSD: arch.c,v 1.17 1996/11/06 17:58:59 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1999,2000 Marc Espie.
6  *
7  * Extensive code changes for the OpenBSD project.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OPENBSD
22  * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 /*
31  * Copyright (c) 1988, 1989, 1990, 1993
32  *	The Regents of the University of California.  All rights reserved.
33  * Copyright (c) 1989 by Berkeley Softworks
34  * All rights reserved.
35  *
36  * This code is derived from software contributed to Berkeley by
37  * Adam de Boor.
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  * 1. Redistributions of source code must retain the above copyright
43  *    notice, this list of conditions and the following disclaimer.
44  * 2. Redistributions in binary form must reproduce the above copyright
45  *    notice, this list of conditions and the following disclaimer in the
46  *    documentation and/or other materials provided with the distribution.
47  * 3. Neither the name of the University nor the names of its contributors
48  *    may be used to endorse or promote products derived from this software
49  *    without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61  * SUCH DAMAGE.
62  */
63 
64 /*
65  *	Once again, cacheing/hashing comes into play in the manipulation
66  * of archives. The first time an archive is referenced, all of its members'
67  * headers are read and hashed and the archive closed again. All hashed
68  * archives are kept in a hash (archives) which is searched each time
69  * an archive member is referenced.
70  *
71  */
72 
73 #include <ar.h>
74 #include <assert.h>
75 #include <ctype.h>
76 #include <fcntl.h>
77 #include <limits.h>
78 #include <stddef.h>
79 #include <stdint.h>
80 #include <stdio.h>
81 #include <stdlib.h>
82 #include <string.h>
83 #include <unistd.h>
84 #include <ohash.h>
85 #include "config.h"
86 #include "defines.h"
87 #include "buf.h"
88 #include "dir.h"
89 #include "direxpand.h"
90 #include "arch.h"
91 #include "var.h"
92 #include "targ.h"
93 #include "memory.h"
94 #include "gnode.h"
95 #include "timestamp.h"
96 #include "lst.h"
97 
98 #ifdef TARGET_MACHINE
99 #undef MACHINE
100 #define MACHINE TARGET_MACHINE
101 #endif
102 #ifdef TARGET_MACHINE_ARCH
103 #undef MACHINE_ARCH
104 #define MACHINE_ARCH TARGET_MACHINE_ARCH
105 #endif
106 #ifdef TARGET_MACHINE_CPU
107 #undef MACHINE_CPU
108 #define MACHINE_CPU TARGET_MACHINE_CPU
109 #endif
110 
111 static struct ohash archives;	/* Archives we've already examined.  */
112 
113 typedef struct Arch_ {
114 	struct ohash members;	/* All the members of this archive, as
115 				 * struct arch_member entries.  */
116 	char name[1];		/* Archive name. */
117 } Arch;
118 
119 #define AR_NAME_SIZE		(sizeof(((struct ar_hdr *)0)->ar_name))
120 #define AR_DATE_SIZE		(sizeof(((struct ar_hdr *)0)->ar_date))
121 
122 /* Each archive member is tied to an arch_member structure,
123  * suitable for hashing.  */
124 struct arch_member {
125 	struct timespec mtime;		/* Member modification date.  */
126 	char date[AR_DATE_SIZE+1];	/* Same, before conversion to numeric
127 					 * value.  */
128 	char name[1];			/* Member name.  */
129 };
130 
131 static struct ohash_info members_info = {
132 	offsetof(struct arch_member, name), NULL,
133 	hash_calloc, hash_free, element_alloc
134 };
135 
136 static struct ohash_info arch_info = {
137 	offsetof(Arch, name), NULL, hash_calloc, hash_free, element_alloc
138 };
139 
140 
141 
142 static struct arch_member *new_arch_member(struct ar_hdr *, const char *);
143 static struct timespec mtime_of_member(struct arch_member *);
144 static long field2long(const char *, size_t);
145 static Arch *read_archive(const char *, const char *);
146 
147 static struct timespec ArchMTimeMember(const char *, const char *, bool);
148 static FILE *ArchFindMember(const char *, const char *, struct ar_hdr *, const char *);
149 static void ArchTouch(const char *, const char *);
150 #if defined(__svr4__) || defined(__SVR4) || \
151     (defined(__OpenBSD__) && defined(__ELF__))
152 #define SVR4ARCHIVES
153 #endif
154 static bool parse_archive(Buffer, const char **, Lst, SymTable *);
155 static void add_archive_node(Lst, const char *);
156 
157 struct SVR4namelist {
158 	char *fnametab;		/* Extended name table strings */
159 	size_t fnamesize;	/* Size of the string table */
160 };
161 
162 #ifdef SVR4ARCHIVES
163 static const char *svr4list = "Archive list";
164 
165 static char *ArchSVR4Entry(struct SVR4namelist *, const char *, size_t, FILE *);
166 #endif
167 
168 static struct arch_member *
169 new_arch_member(struct ar_hdr *hdr, const char *name)
170 {
171 	const char *end = NULL;
172 	struct arch_member *n;
173 
174 	n = ohash_create_entry(&members_info, name, &end);
175 	/* XXX ar entries are NOT null terminated.	*/
176 	memcpy(n->date, &(hdr->ar_date), AR_DATE_SIZE);
177 	n->date[AR_DATE_SIZE] = '\0';
178 	/* Don't compute mtime before it is needed. */
179 	ts_set_out_of_date(n->mtime);
180 	return n;
181 }
182 
183 static struct timespec
184 mtime_of_member(struct arch_member *m)
185 {
186 	if (is_out_of_date(m->mtime))
187 		ts_set_from_time_t((time_t) strtoll(m->date, NULL, 10),
188 		    m->mtime);
189 	return m->mtime;
190 }
191 
192 bool
193 Arch_ParseArchive(const char **line, Lst nodes, SymTable *ctxt)
194 {
195 	bool result;
196 	static BUFFER expand;
197 
198 	Buf_Reinit(&expand, MAKE_BSIZE);
199 	result = parse_archive(&expand, line, nodes, ctxt);
200 	return result;
201 }
202 
203 static void
204 add_archive_node(Lst nodes, const char *name)
205 {
206 	GNode *gn;
207 
208 	gn = Targ_FindNode(name, TARG_CREATE);
209 	gn->type |= OP_ARCHV;
210 	Lst_AtEnd(nodes, gn);
211 }
212 
213 static bool
214 parse_archive(Buffer expand, const char **linePtr, Lst nodeLst, SymTable *ctxt)
215 {
216 	const char *cp;    	/* Pointer into line */
217 	const char *lib;	/* Library-part of specification */
218 	const char *elib;
219 	const char *member;    	/* Member-part of specification */
220 	const char *emember;
221 	bool subst_lib;
222 
223 	/* figure out the library name part */
224 	lib = *linePtr;
225 	subst_lib = false;
226 
227 	for (cp = lib; *cp != '(' && *cp != '\0';) {
228 		if (*cp == '$') {
229 			if (!Var_ParseSkip(&cp, ctxt))
230 				return false;
231 			subst_lib = true;
232 		} else
233 			cp++;
234 	}
235 
236 	elib = cp;
237 	if (subst_lib) {
238 		lib = Var_Substi(lib, elib, ctxt, true);
239 		elib = lib + strlen(lib);
240 	}
241 
242 	if (*cp == '\0') {
243 		printf("Unclosed parenthesis in archive specification\n");
244 		return false;
245 	}
246 	cp++;
247 	/* iterate on members, that may be separated by spaces */
248 	for (;;) {
249 		/* First skip to the start of the member's name, mark that
250 		 * place and skip to the end of it (either white-space or
251 		 * a close paren).  */
252 		bool subst_member = false;
253 
254 		while (ISSPACE(*cp))
255 			cp++;
256 		member = cp;
257 		while (*cp != '\0' && *cp != ')' && !ISSPACE(*cp)) {
258 			if (*cp == '$') {
259 				if (!Var_ParseSkip(&cp, ctxt))
260 					return false;
261 				subst_member = true;
262 			} else
263 				cp++;
264 		}
265 
266 		/* If the specification ends without a closing parenthesis,
267 		 * chances are there's something wrong (like a missing
268 		 * backslash), so it's better to return failure than allow such
269 		 * things to happen.  */
270 		if (*cp == '\0' || ISSPACE(*cp)) {
271 			printf("No closing parenthesis in archive specification\n");
272 			return false;
273 		}
274 
275 		/* If we didn't move anywhere, we must be done.  */
276 		if (cp == member)
277 			break;
278 
279 		emember = cp;
280 
281 		/* XXX: This should be taken care of intelligently by
282 		 * SuffExpandChildren, both for the archive and the member
283 		 * portions.  */
284 
285 		/* If member contains variables, try and substitute for them.
286 		 * This will slow down archive specs with dynamic sources, of
287 		 * course, since we'll be (non-)substituting them three times,
288 		 * but them's the breaks -- we need to do this since
289 		 * SuffExpandChildren calls us, otherwise we could assume the
290 		 * thing would be taken care of later.  */
291 		if (subst_member) {
292 			const char *oldMemberName = member;
293 			const char *result;
294 
295 			member = Var_Substi(member, emember, ctxt, true);
296 
297 			/* Now form an archive spec and recurse to deal with
298 			 * nested variables and multi-word variable values....
299 			 * The results are just placed at the end of the
300 			 * nodeLst we're returning.  */
301 			Buf_Addi(expand, lib, elib);
302 			Buf_AddChar(expand, '(');
303 			Buf_AddString(expand, member);
304 			Buf_AddChar(expand, ')');
305 			result = Buf_Retrieve(expand);
306 
307 			if (strchr(member, '$') &&
308 			    memcmp(member, oldMemberName,
309 				emember - oldMemberName) == 0) {
310 				/* Must contain dynamic sources, so we can't
311 				 * deal with it now.  let SuffExpandChildren
312 				 * handle it later  */
313 				add_archive_node(nodeLst, result);
314 			} else if (!Arch_ParseArchive(&result, nodeLst, ctxt))
315 				return false;
316 			Buf_Reset(expand);
317 		} else if (Dir_HasWildcardsi(member, emember)) {
318 			LIST  members;
319 			char  *m;
320 
321 			Lst_Init(&members);
322 
323 			Dir_Expandi(member, emember, defaultPath, &members);
324 			while ((m = Lst_DeQueue(&members)) != NULL) {
325 				Buf_Addi(expand, lib, elib);
326 				Buf_AddChar(expand, '(');
327 				Buf_AddString(expand, m);
328 				Buf_AddChar(expand, ')');
329 				free(m);
330 				add_archive_node(nodeLst, Buf_Retrieve(expand));
331 				Buf_Reset(expand);
332 			}
333 		} else {
334 			Buf_Addi(expand, lib, elib);
335 			Buf_AddChar(expand, '(');
336 			Buf_Addi(expand, member, emember);
337 			Buf_AddChar(expand, ')');
338 			add_archive_node(nodeLst, Buf_Retrieve(expand));
339 			Buf_Reset(expand);
340 		}
341 		if (subst_member)
342 			free((char *)member);
343 
344 	}
345 
346 	if (subst_lib)
347 		free((char *)lib);
348 
349 	/* We promised the pointer would be set up at the next non-space, so
350 	 * we must advance cp there before setting *linePtr... (note that on
351 	 * entrance to the loop, cp is guaranteed to point at a ')') */
352 	do {
353 		cp++;
354 	} while (ISSPACE(*cp));
355 
356 	*linePtr = cp;
357 	return true;
358 }
359 
360 /* Helper function: ar fields are not null terminated.	*/
361 static long
362 field2long(const char *field, size_t length)
363 {
364 	static char enough[32];
365 
366 	assert(length < sizeof(enough));
367 	memcpy(enough, field, length);
368 	enough[length] = '\0';
369 	return strtol(enough, NULL, 10);
370 }
371 
372 static Arch *
373 read_archive(const char *archive, const char *earchive)
374 {
375 	FILE *arch;       /* Stream to archive */
376 	char magic[SARMAG];
377 	Arch *ar;
378 	struct SVR4namelist list;
379 
380 	list.fnametab = NULL;
381 
382 	/* When we encounter an archive for the first time, we read its
383 	 * whole contents, to place it in the cache.  */
384 	arch = fopen(archive, "r");
385 	if (arch == NULL)
386 		return NULL;
387 
388 	/* Make sure this is an archive we can handle.  */
389 	if ((fread(magic, SARMAG, 1, arch) != 1) ||
390 	    (strncmp(magic, ARMAG, SARMAG) != 0)) {
391 		fclose(arch);
392 		return NULL;
393 	}
394 
395 	ar = ohash_create_entry(&arch_info, archive, &earchive);
396 	ohash_init(&ar->members, 8, &members_info);
397 
398 	for (;;) {
399 		size_t n;
400 		struct ar_hdr arHeader;	/* Archive-member header */
401 		off_t size;		/* Size of archive member */
402 		char buffer[PATH_MAX];
403 		char *memberName; 	/* Current member name while hashing. */
404 		char *cp;
405 
406 		memberName = buffer;
407 		n = fread(&arHeader, 1, sizeof(struct ar_hdr), arch);
408 
409 		/*  Whole archive read ok.  */
410 		if (n == 0 && feof(arch)) {
411 			free(list.fnametab);
412 			fclose(arch);
413 			return ar;
414 		}
415 		if (n < sizeof(struct ar_hdr))
416 			break;
417 
418 		if (memcmp(arHeader.ar_fmag, ARFMAG, sizeof(arHeader.ar_fmag))
419 		    != 0) {
420 			/* header is bogus.  */
421 			break;
422 		} else {
423 			/* We need to advance the stream's pointer to the start
424 			 * of the next header.  Records are padded with
425 			 * newlines to an even-byte boundary, so we need to
426 			 * extract the size of the record and round it up
427 			 * during the seek.  */
428 			size = (off_t) field2long(arHeader.ar_size,
429 			    sizeof(arHeader.ar_size));
430 
431 			(void)memcpy(memberName, arHeader.ar_name,
432 			    AR_NAME_SIZE);
433 			/* Find real end of name (strip extraneous ' ')  */
434 			for (cp = memberName + AR_NAME_SIZE - 1; *cp == ' ';)
435 				cp--;
436 			cp[1] = '\0';
437 
438 #ifdef SVR4ARCHIVES
439 			/* SVR4 names are slash terminated.  Also svr4 extended
440 			 * AR format.
441 			 */
442 			if (memberName[0] == '/') {
443 				/* SVR4 magic mode.  */
444 				memberName = ArchSVR4Entry(&list, memberName,
445 				    size, arch);
446 				if (memberName == NULL)
447 					/* Invalid data */
448 					break;
449 				else if (memberName == svr4list)
450 					/* List of files entry */
451 					continue;
452 				/* Got the entry.  */
453 				/* XXX this assumes further processing, such as
454 				 * AR_EFMT1, also applies to SVR4ARCHIVES.  */
455 			}
456 			else {
457 				if (cp[0] == '/')
458 					cp[0] = '\0';
459 			}
460 #endif
461 
462 #ifdef AR_EFMT1
463 			/* BSD 4.4 extended AR format: #1/<namelen>, with name
464 			 * as the first <namelen> bytes of the file.  */
465 			if (memcmp(memberName, AR_EFMT1, sizeof(AR_EFMT1) - 1)
466 			    == 0 && ISDIGIT(memberName[sizeof(AR_EFMT1) - 1])) {
467 
468 				int elen = atoi(memberName +
469 				    sizeof(AR_EFMT1)-1);
470 
471 				if (elen <= 0 || elen >= PATH_MAX)
472 					break;
473 				memberName = buffer;
474 				if (fread(memberName, elen, 1, arch) != 1)
475 					break;
476 				memberName[elen] = '\0';
477 				if (fseek(arch, -elen, SEEK_CUR) != 0)
478 					break;
479 				if (DEBUG(ARCH) || DEBUG(MAKE))
480 					printf("ArchStat: Extended format entry for %s\n",
481 					    memberName);
482 			}
483 #endif
484 
485 			ohash_insert(&ar->members,
486 			    ohash_qlookup(&ar->members, memberName),
487 				new_arch_member(&arHeader, memberName));
488 		}
489 		if (fseek(arch, (size + 1) & ~1, SEEK_CUR) != 0)
490 			break;
491 	}
492 
493 	fclose(arch);
494 	ohash_delete(&ar->members);
495 	free(list.fnametab);
496 	free(ar);
497 	return NULL;
498 }
499 
500 /*-
501  *-----------------------------------------------------------------------
502  * ArchMTimeMember --
503  *	Find the modification time of an archive's member, given the
504  *	path to the archive and the path to the desired member.
505  *
506  * Results:
507  *	The archive member's modification time, or OUT_OF_DATE if member
508  *	was not found (convenient, so that missing members are always
509  *	out of date).
510  *
511  * Side Effects:
512  *	Cache the whole archive contents if hash is true.
513  *-----------------------------------------------------------------------
514  */
515 static struct timespec
516 ArchMTimeMember(
517     const char *archive,	/* Path to the archive */
518     const char *member, 	/* Name of member. If it is a path, only the
519 				 * last component is used. */
520     bool hash)       		/* true if archive should be hashed if not
521 				 * already so. */
522 {
523 	FILE *arch;     	/* Stream to archive */
524 	Arch *ar;		/* Archive descriptor */
525 	unsigned int slot;	/* Place of archive in the archives hash */
526 	const char *end = NULL;
527 	const char *cp;
528 	struct timespec result;
529 
530 	ts_set_out_of_date(result);
531 	/* Because of space constraints and similar things, files are archived
532 	 * using their final path components, not the entire thing, so we need
533 	 * to point 'member' to the final component, if there is one, to make
534 	 * the comparisons easier...  */
535 	cp = strrchr(member, '/');
536 	if (cp != NULL)
537 		member = cp + 1;
538 
539 	/* Try to find archive in cache.  */
540 	slot = ohash_qlookupi(&archives, archive, &end);
541 	ar = ohash_find(&archives, slot);
542 
543 	/* If not found, get it now.  */
544 	if (ar == NULL) {
545 		if (!hash) {
546 			/* Quick path:  no need to hash the whole archive, just
547 			 * use ArchFindMember to get the member's header and
548 			 * close the stream again.  */
549 			struct ar_hdr arHeader;
550 
551 			arch = ArchFindMember(archive, member, &arHeader, "r");
552 
553 			if (arch != NULL) {
554 				fclose(arch);
555 				ts_set_from_time_t(
556 				    (time_t)strtol(arHeader.ar_date, NULL, 10),
557 				    result);
558 			}
559 			return result;
560 		}
561 		ar = read_archive(archive, end);
562 		if (ar != NULL)
563 			ohash_insert(&archives, slot, ar);
564 	}
565 
566 	/* If archive was found, get entry we seek.  */
567 	if (ar != NULL) {
568 		struct arch_member *he;
569 		end = NULL;
570 
571 		he = ohash_find(&ar->members, ohash_qlookupi(&ar->members,
572 		    member, &end));
573 		if (he != NULL)
574 			return mtime_of_member(he);
575 		else {
576 			if ((size_t)(end - member) > AR_NAME_SIZE) {
577 				/* Try truncated name.	*/
578 				end = member + AR_NAME_SIZE;
579 				he = ohash_find(&ar->members,
580 				    ohash_qlookupi(&ar->members, member, &end));
581 				if (he != NULL)
582 					return mtime_of_member(he);
583 			}
584 		}
585 	}
586 	return result;
587 }
588 
589 #ifdef SVR4ARCHIVES
590 /*-
591  *-----------------------------------------------------------------------
592  * ArchSVR4Entry --
593  *	Parse an SVR4 style entry that begins with a slash.
594  *	If it is "//", then load the table of filenames
595  *	If it is "/<offset>", then try to substitute the long file name
596  *	from offset of a table previously read.
597  *
598  * Results:
599  *	svr4list: just read a list of names
600  *	NULL:	  error occurred
601  *	extended name
602  *
603  * Side-effect:
604  *	For a list of names, store the list in l.
605  *-----------------------------------------------------------------------
606  */
607 
608 static char *
609 ArchSVR4Entry(struct SVR4namelist *l, const char *name, size_t size, FILE *arch)
610 {
611 #define ARLONGNAMES1 "/"
612 #define ARLONGNAMES2 "ARFILENAMES"
613 	size_t entry;
614 	char *ptr, *eptr;
615 
616 	assert(name[0] == '/');
617 	name++;
618 	/* First comes a table of archive names, to be used by subsequent
619 	 * calls.  */
620 	if (memcmp(name, ARLONGNAMES1, sizeof(ARLONGNAMES1) - 1) == 0 ||
621 	    memcmp(name, ARLONGNAMES2, sizeof(ARLONGNAMES2) - 1) == 0) {
622 
623 		if (l->fnametab != NULL) {
624 			if (DEBUG(ARCH))
625 				printf("Attempted to redefine an SVR4 name table\n");
626 			return NULL;
627 		}
628 
629 		l->fnametab = emalloc(size);
630 		l->fnamesize = size;
631 
632 		if (fread(l->fnametab, size, 1, arch) != 1) {
633 			if (DEBUG(ARCH))
634 				printf("Reading an SVR4 name table failed\n");
635 			return NULL;
636 		}
637 
638 		eptr = l->fnametab + size;
639 		for (entry = 0, ptr = l->fnametab; ptr < eptr; ptr++)
640 			switch (*ptr) {
641 			case '/':
642 				entry++;
643 				*ptr = '\0';
644 				break;
645 
646 			case '\n':
647 				break;
648 
649 			default:
650 				break;
651 			}
652 		if (DEBUG(ARCH))
653 			printf("Found svr4 archive name table with %zu entries\n",
654 			    entry);
655 		return (char *)svr4list;
656 	}
657 	/* Then the names themselves are given as offsets in this table.  */
658 	if (*name == ' ' || *name == '\0')
659 		return NULL;
660 
661 	entry = (size_t) strtol(name, &eptr, 0);
662 	if ((*eptr != ' ' && *eptr != '\0') || eptr == name) {
663 		if (DEBUG(ARCH))
664 			printf("Could not parse SVR4 name /%s\n", name);
665 		return NULL;
666 	}
667 	if (entry >= l->fnamesize) {
668 		if (DEBUG(ARCH))
669 			printf("SVR4 entry offset /%s is greater than %zu\n",
670 			    name, l->fnamesize);
671 		return NULL;
672 	}
673 
674 	if (DEBUG(ARCH))
675 		printf("Replaced /%s with %s\n", name, l->fnametab + entry);
676 
677 	return l->fnametab + entry;
678 }
679 #endif
680 
681 
682 /*-
683  *-----------------------------------------------------------------------
684  * ArchFindMember --
685  *	Locate a member of an archive, given the path of the archive and
686  *	the path of the desired member. If the archive is to be modified,
687  *	the mode should be "r+", if not, it should be "r".
688  *
689  * Results:
690  *	A FILE *, opened for reading and writing, positioned right after
691  *	the member's header, or NULL if the member was nonexistent.
692  *
693  * Side Effects:
694  *	Fill the struct ar_hdr pointed by arHeaderPtr.
695  *-----------------------------------------------------------------------
696  */
697 static FILE *
698 ArchFindMember(
699     const char	  *archive,   /* Path to the archive */
700     const char	  *member,    /* Name of member. If it is a path, only the
701 			       * last component is used. */
702     struct ar_hdr *arHeaderPtr,/* Pointer to header structure to be filled in */
703     const char	  *mode)      /* mode for opening the stream */
704 {
705 	FILE *	  arch;       /* Stream to archive */
706 	char	  *cp;
707 	char	  magic[SARMAG];
708 	size_t	  length;
709 	struct SVR4namelist list;
710 
711 	list.fnametab = NULL;
712 
713 	arch = fopen(archive, mode);
714 	if (arch == NULL)
715 		return NULL;
716 
717 	/* Make sure this is an archive we can handle.  */
718 	if (fread(magic, SARMAG, 1, arch) != 1 ||
719 	    strncmp(magic, ARMAG, SARMAG) != 0) {
720 		fclose(arch);
721 		return NULL;
722 	}
723 
724 	/* Because of space constraints and similar things, files are archived
725 	 * using their final path components, not the entire thing, so we need
726 	 * to point 'member' to the final component, if there is one, to make
727 	 * the comparisons easier...  */
728 	cp = strrchr(member, '/');
729 	if (cp != NULL)
730 		member = cp + 1;
731 
732 	length = strlen(member);
733 	if (length >= AR_NAME_SIZE)
734 		length = AR_NAME_SIZE;
735 
736 	/* Error handling is simpler than for read_archive, since we just
737 	 * look for a given member.  */
738 	while (fread(arHeaderPtr, sizeof(struct ar_hdr), 1, arch) == 1) {
739 		off_t size;       /* Size of archive member */
740 		char *memberName;
741 
742 		if (memcmp(arHeaderPtr->ar_fmag, ARFMAG,
743 		    sizeof(arHeaderPtr->ar_fmag) ) != 0)
744 			 /* The header is bogus, so the archive is bad.  */
745 			 break;
746 
747 		memberName = arHeaderPtr->ar_name;
748 		if (memcmp(member, memberName, length) == 0) {
749 			/* If the member's name doesn't take up the entire
750 			 * 'name' field, we have to be careful of matching
751 			 * prefixes. Names are space- padded to the right, so
752 			 * if the character in 'name' at the end of the matched
753 			 * string is anything but a space, this isn't the
754 			 * member we sought.  */
755 #ifdef SVR4ARCHIVES
756 			if (length < sizeof(arHeaderPtr->ar_name) &&
757 			    memberName[length] == '/')
758 				length++;
759 #endif
760 			if (length == sizeof(arHeaderPtr->ar_name) ||
761 			    memberName[length] == ' ') {
762 				free(list.fnametab);
763 				return arch;
764 			}
765 		}
766 
767 		size = (off_t) field2long(arHeaderPtr->ar_size,
768 		    sizeof(arHeaderPtr->ar_size));
769 
770 #ifdef SVR4ARCHIVES
771 		/* svr4 names are slash terminated. Also svr4 extended AR
772 		 * format.
773 		 */
774 		if (memberName[0] == '/') {
775 			/* svr4 magic mode.  */
776 			memberName = ArchSVR4Entry(&list, arHeaderPtr->ar_name,
777 			    size, arch);
778 			if (memberName == NULL)
779 				/* Invalid data */
780 				break;
781 			else if (memberName == svr4list)
782 				/* List of files entry */
783 				continue;
784 			/* Got the entry.  */
785 			if (strcmp(memberName, member) == 0) {
786 				free(list.fnametab);
787 				return arch;
788 			}
789 		}
790 #endif
791 
792 #ifdef AR_EFMT1
793 		/* BSD 4.4 extended AR format: #1/<namelen>, with name as the
794 		 * first <namelen> bytes of the file.  */
795 		if (memcmp(memberName, AR_EFMT1, sizeof(AR_EFMT1) - 1) == 0 &&
796 		    ISDIGIT(memberName[sizeof(AR_EFMT1) - 1])) {
797 			char ename[PATH_MAX];
798 
799 			int elength = atoi(memberName + sizeof(AR_EFMT1)-1);
800 
801 			if (elength <= 0 || elength >= PATH_MAX)
802 				break;
803 			if (fread(ename, elength, 1, arch) != 1)
804 				break;
805 			if (fseek(arch, -elength, SEEK_CUR) != 0)
806 				break;
807 			ename[elength] = '\0';
808 			if (DEBUG(ARCH) || DEBUG(MAKE))
809 				printf("ArchFind: Extended format entry for %s\n", ename);
810 			/* Found as extended name.	*/
811 			if (strcmp(ename, member) == 0) {
812 				free(list.fnametab);
813 				return arch;
814 			}
815 		}
816 #endif
817 		/* This isn't the member we're after, so we need to advance the
818 		 * stream's pointer to the start of the next header.  */
819 		if (fseek(arch, (size + 1) & ~1, SEEK_CUR) != 0)
820 			break;
821 	}
822 
823 	/* We did not find the member, or we ran into an error while reading
824 	 * the archive.  */
825 #ifdef SVRARCHIVES
826 	free(list.fnametab);
827 #endif
828 	fclose(arch);
829 	return NULL;
830 }
831 
832 static void
833 ArchTouch(const char *archive, const char *member)
834 {
835 	FILE *arch;
836 	struct ar_hdr arHeader;
837 
838 	arch = ArchFindMember(archive, member, &arHeader, "r+");
839 	if (arch != NULL) {
840 		snprintf(arHeader.ar_date, sizeof(arHeader.ar_date),
841 		    "%-12ld", (long) time(NULL));
842 		if (fseek(arch, -sizeof(struct ar_hdr), SEEK_CUR) == 0)
843 			(void)fwrite(&arHeader, sizeof(struct ar_hdr), 1, arch);
844 		fclose(arch);
845 	}
846 }
847 
848 /*
849  * Side Effects:
850  *	The modification time of the entire archive is also changed.
851  *	For a library, this could necessitate the re-ranlib'ing of the
852  *	whole thing.
853  */
854 void
855 Arch_Touch(GNode *gn)
856 {
857 	ArchTouch(Var(ARCHIVE_INDEX, gn), Var(MEMBER_INDEX, gn));
858 }
859 
860 struct timespec
861 Arch_MTime(GNode *gn)
862 {
863 	gn->mtime = ArchMTimeMember(Var(ARCHIVE_INDEX, gn),
864 	     Var(MEMBER_INDEX, gn), true);
865 
866 	return gn->mtime;
867 }
868 
869 struct timespec
870 Arch_MemMTime(GNode *gn)
871 {
872 	LstNode ln;
873 
874 	for (ln = Lst_First(&gn->parents); ln != NULL; ln = Lst_Adv(ln)) {
875 		GNode *pgn;
876 		char *nameStart;
877 		char *nameEnd;
878 
879 		pgn = Lst_Datum(ln);
880 
881 		if (pgn->type & OP_ARCHV) {
882 			/* If the parent is an archive specification and is
883 			 * being built and its member's name matches the name of
884 			 * the node we were given, record the modification time
885 			 * of the parent in the child. We keep searching its
886 			 * parents in case some other parent requires this
887 			 * child to exist...  */
888 			if ((nameStart = strchr(pgn->name, '(') ) != NULL) {
889 				nameStart++;
890 				nameEnd = strchr(nameStart, ')');
891 			} else
892 				nameEnd = NULL;
893 
894 			if (pgn->must_make && nameEnd != NULL &&
895 			    strncmp(nameStart, gn->name, nameEnd - nameStart)
896 			    == 0 && gn->name[nameEnd-nameStart] == '\0')
897 				gn->mtime = Arch_MTime(pgn);
898 		} else if (pgn->must_make) {
899 			/* Something which isn't a library depends on the
900 			 * existence of this target, so it needs to exist.  */
901 			ts_set_out_of_date(gn->mtime);
902 			break;
903 		}
904 	}
905 	return gn->mtime;
906 }
907 
908 void
909 Arch_Init(void)
910 {
911 	ohash_init(&archives, 4, &arch_info);
912 }
913