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arch.c revision 1.5
      1 /*
      2  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
      3  * Copyright (c) 1988, 1989 by Adam de Boor
      4  * Copyright (c) 1989 by Berkeley Softworks
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Adam de Boor.
      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. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the University of
     21  *	California, Berkeley and its contributors.
     22  * 4. Neither the name of the University nor the names of its contributors
     23  *    may be used to endorse or promote products derived from this software
     24  *    without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  */
     38 
     39 #ifndef lint
     40 /* from: static char sccsid[] = "@(#)arch.c	5.7 (Berkeley) 12/28/90"; */
     41 static char *rcsid = "$Id: arch.c,v 1.5 1994/03/05 00:34:32 cgd Exp $";
     42 #endif /* not lint */
     43 
     44 /*-
     45  * arch.c --
     46  *	Functions to manipulate libraries, archives and their members.
     47  *
     48  *	Once again, cacheing/hashing comes into play in the manipulation
     49  * of archives. The first time an archive is referenced, all of its members'
     50  * headers are read and hashed and the archive closed again. All hashed
     51  * archives are kept on a list which is searched each time an archive member
     52  * is referenced.
     53  *
     54  * The interface to this module is:
     55  *	Arch_ParseArchive   	Given an archive specification, return a list
     56  *	    	  	    	of GNode's, one for each member in the spec.
     57  *	    	  	    	FAILURE is returned if the specification is
     58  *	    	  	    	invalid for some reason.
     59  *
     60  *	Arch_Touch	    	Alter the modification time of the archive
     61  *	    	  	    	member described by the given node to be
     62  *	    	  	    	the current time.
     63  *
     64  *	Arch_TouchLib	    	Update the modification time of the library
     65  *	    	  	    	described by the given node. This is special
     66  *	    	  	    	because it also updates the modification time
     67  *	    	  	    	of the library's table of contents.
     68  *
     69  *	Arch_MTime	    	Find the modification time of a member of
     70  *	    	  	    	an archive *in the archive*. The time is also
     71  *	    	  	    	placed in the member's GNode. Returns the
     72  *	    	  	    	modification time.
     73  *
     74  *	Arch_MemTime	    	Find the modification time of a member of
     75  *	    	  	    	an archive. Called when the member doesn't
     76  *	    	  	    	already exist. Looks in the archive for the
     77  *	    	  	    	modification time. Returns the modification
     78  *	    	  	    	time.
     79  *
     80  *	Arch_FindLib	    	Search for a library along a path. The
     81  *	    	  	    	library name in the GNode should be in
     82  *	    	  	    	-l<name> format.
     83  *
     84  *	Arch_LibOODate	    	Special function to decide if a library node
     85  *	    	  	    	is out-of-date.
     86  *
     87  *	Arch_Init 	    	Initialize this module.
     88  */
     89 
     90 #include    <sys/types.h>
     91 #include    <sys/stat.h>
     92 #include    <sys/time.h>
     93 #include    <ctype.h>
     94 #include    <ar.h>
     95 #include    <ranlib.h>
     96 #include    <stdio.h>
     97 #include    "make.h"
     98 #include    "hash.h"
     99 #include    "dir.h"
    100 #include    "config.h"
    101 
    102 static Lst	  archives;   /* Lst of archives we've already examined */
    103 
    104 typedef struct Arch {
    105     char	  *name;      /* Name of archive */
    106     Hash_Table	  members;    /* All the members of the archive described
    107 			       * by <name, struct ar_hdr *> key/value pairs */
    108 } Arch;
    109 
    110 static int ArchFindArchive __P((Arch *, char *));
    111 static struct ar_hdr *ArchStatMember __P((char *, char *, Boolean));
    112 static FILE *ArchFindMember __P((char *, char *, struct ar_hdr *, char *));
    113 
    114 /*-
    115  *-----------------------------------------------------------------------
    116  * Arch_ParseArchive --
    117  *	Parse the archive specification in the given line and find/create
    118  *	the nodes for the specified archive members, placing their nodes
    119  *	on the given list.
    120  *
    121  * Results:
    122  *	SUCCESS if it was a valid specification. The linePtr is updated
    123  *	to point to the first non-space after the archive spec. The
    124  *	nodes for the members are placed on the given list.
    125  *
    126  * Side Effects:
    127  *	Some nodes may be created. The given list is extended.
    128  *
    129  *-----------------------------------------------------------------------
    130  */
    131 ReturnStatus
    132 Arch_ParseArchive (linePtr, nodeLst, ctxt)
    133     char	    **linePtr;      /* Pointer to start of specification */
    134     Lst	    	    nodeLst;   	    /* Lst on which to place the nodes */
    135     GNode   	    *ctxt;  	    /* Context in which to expand variables */
    136 {
    137     register char   *cp;	    /* Pointer into line */
    138     GNode	    *gn;     	    /* New node */
    139     char	    *libName;  	    /* Library-part of specification */
    140     char	    *memName;  	    /* Member-part of specification */
    141     char	    nameBuf[MAKE_BSIZE]; /* temporary place for node name */
    142     char	    saveChar;  	    /* Ending delimiter of member-name */
    143     Boolean 	    subLibName;	    /* TRUE if libName should have/had
    144 				     * variable substitution performed on it */
    145 
    146     libName = *linePtr;
    147 
    148     subLibName = FALSE;
    149 
    150     for (cp = libName; *cp != '(' && *cp != '\0'; cp++) {
    151 	if (*cp == '$') {
    152 	    /*
    153 	     * Variable spec, so call the Var module to parse the puppy
    154 	     * so we can safely advance beyond it...
    155 	     */
    156 	    int 	length;
    157 	    Boolean	freeIt;
    158 	    char	*result;
    159 
    160 	    result=Var_Parse(cp, ctxt, TRUE, &length, &freeIt);
    161 	    if (result == var_Error) {
    162 		return(FAILURE);
    163 	    } else {
    164 		subLibName = TRUE;
    165 	    }
    166 
    167 	    if (freeIt) {
    168 		free(result);
    169 	    }
    170 	    cp += length-1;
    171 	}
    172     }
    173 
    174     *cp++ = '\0';
    175     if (subLibName) {
    176 	libName = Var_Subst(NULL, libName, ctxt, TRUE);
    177     }
    178 
    179 
    180     for (;;) {
    181 	/*
    182 	 * First skip to the start of the member's name, mark that
    183 	 * place and skip to the end of it (either white-space or
    184 	 * a close paren).
    185 	 */
    186 	Boolean	doSubst = FALSE; /* TRUE if need to substitute in memName */
    187 
    188 	while (*cp != '\0' && *cp != ')' && isspace (*cp)) {
    189 	    cp++;
    190 	}
    191 	memName = cp;
    192 	while (*cp != '\0' && *cp != ')' && !isspace (*cp)) {
    193 	    if (*cp == '$') {
    194 		/*
    195 		 * Variable spec, so call the Var module to parse the puppy
    196 		 * so we can safely advance beyond it...
    197 		 */
    198 		int 	length;
    199 		Boolean	freeIt;
    200 		char	*result;
    201 
    202 		result=Var_Parse(cp, ctxt, TRUE, &length, &freeIt);
    203 		if (result == var_Error) {
    204 		    return(FAILURE);
    205 		} else {
    206 		    doSubst = TRUE;
    207 		}
    208 
    209 		if (freeIt) {
    210 		    free(result);
    211 		}
    212 		cp += length;
    213 	    } else {
    214 		cp++;
    215 	    }
    216 	}
    217 
    218 	/*
    219 	 * If the specification ends without a closing parenthesis,
    220 	 * chances are there's something wrong (like a missing backslash),
    221 	 * so it's better to return failure than allow such things to happen
    222 	 */
    223 	if (*cp == '\0') {
    224 	    printf("No closing parenthesis in archive specification\n");
    225 	    return (FAILURE);
    226 	}
    227 
    228 	/*
    229 	 * If we didn't move anywhere, we must be done
    230 	 */
    231 	if (cp == memName) {
    232 	    break;
    233 	}
    234 
    235 	saveChar = *cp;
    236 	*cp = '\0';
    237 
    238 	/*
    239 	 * XXX: This should be taken care of intelligently by
    240 	 * SuffExpandChildren, both for the archive and the member portions.
    241 	 */
    242 	/*
    243 	 * If member contains variables, try and substitute for them.
    244 	 * This will slow down archive specs with dynamic sources, of course,
    245 	 * since we'll be (non-)substituting them three times, but them's
    246 	 * the breaks -- we need to do this since SuffExpandChildren calls
    247 	 * us, otherwise we could assume the thing would be taken care of
    248 	 * later.
    249 	 */
    250 	if (doSubst) {
    251 	    char    *buf;
    252 	    char    *sacrifice;
    253 	    char    *oldMemName = memName;
    254 
    255 	    memName = Var_Subst(NULL, memName, ctxt, TRUE);
    256 
    257 	    /*
    258 	     * Now form an archive spec and recurse to deal with nested
    259 	     * variables and multi-word variable values.... The results
    260 	     * are just placed at the end of the nodeLst we're returning.
    261 	     */
    262 	    buf = sacrifice = emalloc(strlen(memName)+strlen(libName)+3);
    263 
    264 	    sprintf(buf, "%s(%s)", libName, memName);
    265 
    266 	    if (strchr(memName, '$') && strcmp(memName, oldMemName) == 0) {
    267 		/*
    268 		 * Must contain dynamic sources, so we can't deal with it now.
    269 		 * Just create an ARCHV node for the thing and let
    270 		 * SuffExpandChildren handle it...
    271 		 */
    272 		gn = Targ_FindNode(buf, TARG_CREATE);
    273 
    274 		if (gn == NILGNODE) {
    275 		    free(buf);
    276 		    return(FAILURE);
    277 		} else {
    278 		    gn->type |= OP_ARCHV;
    279 		    (void)Lst_AtEnd(nodeLst, (ClientData)gn);
    280 		}
    281 	    } else if (Arch_ParseArchive(&sacrifice, nodeLst, ctxt)!=SUCCESS) {
    282 		/*
    283 		 * Error in nested call -- free buffer and return FAILURE
    284 		 * ourselves.
    285 		 */
    286 		free(buf);
    287 		return(FAILURE);
    288 	    }
    289 	    /*
    290 	     * Free buffer and continue with our work.
    291 	     */
    292 	    free(buf);
    293 	} else if (Dir_HasWildcards(memName)) {
    294 	    Lst	  members = Lst_Init(FALSE);
    295 	    char  *member;
    296 
    297 	    Dir_Expand(memName, dirSearchPath, members);
    298 	    while (!Lst_IsEmpty(members)) {
    299 		member = (char *)Lst_DeQueue(members);
    300 
    301 		sprintf(nameBuf, "%s(%s)", libName, member);
    302 		free(member);
    303 		gn = Targ_FindNode (nameBuf, TARG_CREATE);
    304 		if (gn == NILGNODE) {
    305 		    return (FAILURE);
    306 		} else {
    307 		    /*
    308 		     * We've found the node, but have to make sure the rest of
    309 		     * the world knows it's an archive member, without having
    310 		     * to constantly check for parentheses, so we type the
    311 		     * thing with the OP_ARCHV bit before we place it on the
    312 		     * end of the provided list.
    313 		     */
    314 		    gn->type |= OP_ARCHV;
    315 		    (void) Lst_AtEnd (nodeLst, (ClientData)gn);
    316 		}
    317 	    }
    318 	    Lst_Destroy(members, NOFREE);
    319 	} else {
    320 	    sprintf(nameBuf, "%s(%s)", libName, memName);
    321 	    gn = Targ_FindNode (nameBuf, TARG_CREATE);
    322 	    if (gn == NILGNODE) {
    323 		return (FAILURE);
    324 	    } else {
    325 		/*
    326 		 * We've found the node, but have to make sure the rest of the
    327 		 * world knows it's an archive member, without having to
    328 		 * constantly check for parentheses, so we type the thing with
    329 		 * the OP_ARCHV bit before we place it on the end of the
    330 		 * provided list.
    331 		 */
    332 		gn->type |= OP_ARCHV;
    333 		(void) Lst_AtEnd (nodeLst, (ClientData)gn);
    334 	    }
    335 	}
    336 	if (doSubst) {
    337 	    free(memName);
    338 	}
    339 
    340 	*cp = saveChar;
    341     }
    342 
    343     /*
    344      * If substituted libName, free it now, since we need it no longer.
    345      */
    346     if (subLibName) {
    347 	free(libName);
    348     }
    349 
    350     /*
    351      * We promised the pointer would be set up at the next non-space, so
    352      * we must advance cp there before setting *linePtr... (note that on
    353      * entrance to the loop, cp is guaranteed to point at a ')')
    354      */
    355     do {
    356 	cp++;
    357     } while (*cp != '\0' && isspace (*cp));
    358 
    359     *linePtr = cp;
    360     return (SUCCESS);
    361 }
    362 
    363 /*-
    364  *-----------------------------------------------------------------------
    365  * ArchFindArchive --
    366  *	See if the given archive is the one we are looking for. Called
    367  *	From ArchStatMember and ArchFindMember via Lst_Find.
    368  *
    369  * Results:
    370  *	0 if it is, non-zero if it isn't.
    371  *
    372  * Side Effects:
    373  *	None.
    374  *
    375  *-----------------------------------------------------------------------
    376  */
    377 static int
    378 ArchFindArchive (ar, archName)
    379     Arch	  *ar;	      	  /* Current list element */
    380     char	  *archName;  	  /* Name we want */
    381 {
    382     return (strcmp (archName, ar->name));
    383 }
    384 
    385 /*-
    386  *-----------------------------------------------------------------------
    387  * ArchStatMember --
    388  *	Locate a member of an archive, given the path of the archive and
    389  *	the path of the desired member.
    390  *
    391  * Results:
    392  *	A pointer to the current struct ar_hdr structure for the member. Note
    393  *	That no position is returned, so this is not useful for touching
    394  *	archive members. This is mostly because we have no assurances that
    395  *	The archive will remain constant after we read all the headers, so
    396  *	there's not much point in remembering the position...
    397  *
    398  * Side Effects:
    399  *
    400  *-----------------------------------------------------------------------
    401  */
    402 static struct ar_hdr *
    403 ArchStatMember (archive, member, hash)
    404     char	  *archive;   /* Path to the archive */
    405     char	  *member;    /* Name of member. If it is a path, only the
    406 			       * last component is used. */
    407     Boolean	  hash;	      /* TRUE if archive should be hashed if not
    408     			       * already so. */
    409 {
    410 #define AR_MAX_NAME_LEN	    (sizeof(arh.ar_name)-1)
    411     FILE *	  arch;	      /* Stream to archive */
    412     int		  size;       /* Size of archive member */
    413     char	  *cp;	      /* Useful character pointer */
    414     char	  magic[SARMAG];
    415     int		  len;
    416     LstNode	  ln;	      /* Lst member containing archive descriptor */
    417     Arch	  *ar;	      /* Archive descriptor */
    418     Hash_Entry	  *he;	      /* Entry containing member's description */
    419     struct ar_hdr arh;        /* archive-member header for reading archive */
    420     char	  memName[AR_MAX_NAME_LEN+1];
    421     	    	    	    /* Current member name while hashing. The name is
    422 			     * truncated to AR_MAX_NAME_LEN bytes, but we need
    423 			     * room for the null byte... */
    424     char    	  copy[AR_MAX_NAME_LEN+1];
    425     	    	    	    /* Holds copy of last path element from member, if
    426 			     * it has to be truncated, so we don't have to
    427 			     * figure it out again once the table is hashed. */
    428 
    429     /*
    430      * Because of space constraints and similar things, files are archived
    431      * using their final path components, not the entire thing, so we need
    432      * to point 'member' to the final component, if there is one, to make
    433      * the comparisons easier...
    434      */
    435     cp = strrchr (member, '/');
    436     if (cp != (char *) NULL) {
    437 	member = cp + 1;
    438     }
    439     len = strlen (member);
    440     if (len > AR_MAX_NAME_LEN) {
    441 	len = AR_MAX_NAME_LEN;
    442 	strncpy(copy, member, AR_MAX_NAME_LEN);
    443 	copy[AR_MAX_NAME_LEN] = '\0';
    444 	member = copy;
    445     }
    446 
    447     ln = Lst_Find (archives, (ClientData) archive, ArchFindArchive);
    448     if (ln != NILLNODE) {
    449 	ar = (Arch *) Lst_Datum (ln);
    450 
    451 	he = Hash_FindEntry (&ar->members, member);
    452 
    453 	if (he != (Hash_Entry *) NULL) {
    454 	    return ((struct ar_hdr *) Hash_GetValue (he));
    455 	} else {
    456 	    return ((struct ar_hdr *) NULL);
    457 	}
    458     }
    459 
    460     if (!hash) {
    461 	/*
    462 	 * Caller doesn't want the thing hashed, just use ArchFindMember
    463 	 * to read the header for the member out and close down the stream
    464 	 * again. Since the archive is not to be hashed, we assume there's
    465 	 * no need to allocate extra room for the header we're returning,
    466 	 * so just declare it static.
    467 	 */
    468 	 static struct ar_hdr	sarh;
    469 
    470 	 arch = ArchFindMember(archive, member, &sarh, "r");
    471 
    472 	 if (arch == (FILE *)NULL) {
    473 	    return ((struct ar_hdr *)NULL);
    474 	} else {
    475 	    fclose(arch);
    476 	    return (&sarh);
    477 	}
    478     }
    479 
    480     /*
    481      * We don't have this archive on the list yet, so we want to find out
    482      * everything that's in it and cache it so we can get at it quickly.
    483      */
    484     arch = fopen (archive, "r");
    485     if (arch == (FILE *) NULL) {
    486 	return ((struct ar_hdr *) NULL);
    487     }
    488 
    489     /*
    490      * We use the ARMAG string to make sure this is an archive we
    491      * can handle...
    492      */
    493     if ((fread (magic, SARMAG, 1, arch) != 1) ||
    494     	(strncmp (magic, ARMAG, SARMAG) != 0)) {
    495 	    fclose (arch);
    496 	    return ((struct ar_hdr *) NULL);
    497     }
    498 
    499     ar = (Arch *)emalloc (sizeof (Arch));
    500     ar->name = strdup (archive);
    501     Hash_InitTable (&ar->members, -1);
    502     memName[AR_MAX_NAME_LEN] = '\0';
    503 
    504     while (fread ((char *)&arh, sizeof (struct ar_hdr), 1, arch) == 1) {
    505 	if (strncmp ( arh.ar_fmag, ARFMAG, sizeof (arh.ar_fmag)) != 0) {
    506 				 /*
    507 				  * The header is bogus, so the archive is bad
    508 				  * and there's no way we can recover...
    509 				  */
    510 				 fclose (arch);
    511 				 Hash_DeleteTable (&ar->members);
    512 				 free ((Address)ar);
    513 				 return ((struct ar_hdr *) NULL);
    514 	} else {
    515 	    (void) strncpy (memName, arh.ar_name, sizeof(arh.ar_name));
    516 	    for (cp = &memName[AR_MAX_NAME_LEN]; *cp == ' '; cp--) {
    517 		continue;
    518 	    }
    519 	    cp[1] = '\0';
    520 
    521 	    he = Hash_CreateEntry (&ar->members, strdup (memName),
    522 				   (Boolean *)NULL);
    523 	    Hash_SetValue (he, (ClientData)emalloc (sizeof (struct ar_hdr)));
    524 	    memcpy ((Address)Hash_GetValue (he), (Address)&arh,
    525 		sizeof (struct ar_hdr));
    526 	}
    527 	/*
    528 	 * We need to advance the stream's pointer to the start of the
    529 	 * next header. Files are padded with newlines to an even-byte
    530 	 * boundary, so we need to extract the size of the file from the
    531 	 * 'size' field of the header and round it up during the seek.
    532 	 */
    533 	arh.ar_size[sizeof(arh.ar_size)-1] = '\0';
    534 	(void) sscanf (arh.ar_size, "%10d", &size);
    535 	fseek (arch, (size + 1) & ~1, 1);
    536     }
    537 
    538     fclose (arch);
    539 
    540     (void) Lst_AtEnd (archives, (ClientData) ar);
    541 
    542     /*
    543      * Now that the archive has been read and cached, we can look into
    544      * the hash table to find the desired member's header.
    545      */
    546     he = Hash_FindEntry (&ar->members, member);
    547 
    548     if (he != (Hash_Entry *) NULL) {
    549 	return ((struct ar_hdr *) Hash_GetValue (he));
    550     } else {
    551 	return ((struct ar_hdr *) NULL);
    552     }
    553 }
    554 
    555 /*-
    556  *-----------------------------------------------------------------------
    557  * ArchFindMember --
    558  *	Locate a member of an archive, given the path of the archive and
    559  *	the path of the desired member. If the archive is to be modified,
    560  *	the mode should be "r+", if not, it should be "r".
    561  *
    562  * Results:
    563  *	An FILE *, opened for reading and writing, positioned at the
    564  *	start of the member's struct ar_hdr, or NULL if the member was
    565  *	nonexistent. The current struct ar_hdr for member.
    566  *
    567  * Side Effects:
    568  *	The passed struct ar_hdr structure is filled in.
    569  *
    570  *-----------------------------------------------------------------------
    571  */
    572 static FILE *
    573 ArchFindMember (archive, member, arhPtr, mode)
    574     char	  *archive;   /* Path to the archive */
    575     char	  *member;    /* Name of member. If it is a path, only the
    576 			       * last component is used. */
    577     struct ar_hdr *arhPtr;    /* Pointer to header structure to be filled in */
    578     char	  *mode;      /* The mode for opening the stream */
    579 {
    580     FILE *	  arch;	      /* Stream to archive */
    581     int		  size;       /* Size of archive member */
    582     char	  *cp;	      /* Useful character pointer */
    583     char	  magic[SARMAG];
    584     int		  len;
    585 
    586     arch = fopen (archive, mode);
    587     if (arch == (FILE *) NULL) {
    588 	return ((FILE *) NULL);
    589     }
    590 
    591     /*
    592      * We use the ARMAG string to make sure this is an archive we
    593      * can handle...
    594      */
    595     if ((fread (magic, SARMAG, 1, arch) != 1) ||
    596     	(strncmp (magic, ARMAG, SARMAG) != 0)) {
    597 	    fclose (arch);
    598 	    return ((FILE *) NULL);
    599     }
    600 
    601     /*
    602      * Because of space constraints and similar things, files are archived
    603      * using their final path components, not the entire thing, so we need
    604      * to point 'member' to the final component, if there is one, to make
    605      * the comparisons easier...
    606      */
    607     cp = strrchr (member, '/');
    608     if (cp != (char *) NULL) {
    609 	member = cp + 1;
    610     }
    611     len = strlen (member);
    612     if (len > sizeof (arhPtr->ar_name)) {
    613 	len = sizeof (arhPtr->ar_name);
    614     }
    615 
    616     while (fread ((char *)arhPtr, sizeof (struct ar_hdr), 1, arch) == 1) {
    617 	if (strncmp(arhPtr->ar_fmag, ARFMAG, sizeof (arhPtr->ar_fmag) ) != 0) {
    618 	     /*
    619 	      * The header is bogus, so the archive is bad
    620 	      * and there's no way we can recover...
    621 	      */
    622 	     fclose (arch);
    623 	     return ((FILE *) NULL);
    624 	} else if (strncmp (member, arhPtr->ar_name, len) == 0) {
    625 	    /*
    626 	     * If the member's name doesn't take up the entire 'name' field,
    627 	     * we have to be careful of matching prefixes. Names are space-
    628 	     * padded to the right, so if the character in 'name' at the end
    629 	     * of the matched string is anything but a space, this isn't the
    630 	     * member we sought.
    631 	     */
    632 	    if (len != sizeof(arhPtr->ar_name) && arhPtr->ar_name[len] != ' '){
    633 		continue;
    634 	    } else {
    635 		/*
    636 		 * To make life easier, we reposition the file at the start
    637 		 * of the header we just read before we return the stream.
    638 		 * In a more general situation, it might be better to leave
    639 		 * the file at the actual member, rather than its header, but
    640 		 * not here...
    641 		 */
    642 		fseek (arch, -sizeof(struct ar_hdr), 1);
    643 		return (arch);
    644 	    }
    645 	} else {
    646 	    /*
    647 	     * This isn't the member we're after, so we need to advance the
    648 	     * stream's pointer to the start of the next header. Files are
    649 	     * padded with newlines to an even-byte boundary, so we need to
    650 	     * extract the size of the file from the 'size' field of the
    651 	     * header and round it up during the seek.
    652 	     */
    653 	    arhPtr->ar_size[sizeof(arhPtr->ar_size)-1] = '\0';
    654 	    (void)sscanf (arhPtr->ar_size, "%10d", &size);
    655 	    fseek (arch, (size + 1) & ~1, 1);
    656 	}
    657     }
    658 
    659     /*
    660      * We've looked everywhere, but the member is not to be found. Close the
    661      * archive and return NULL -- an error.
    662      */
    663     fclose (arch);
    664     return ((FILE *) NULL);
    665 }
    666 
    667 /*-
    668  *-----------------------------------------------------------------------
    669  * Arch_Touch --
    670  *	Touch a member of an archive.
    671  *
    672  * Results:
    673  *	The 'time' field of the member's header is updated.
    674  *
    675  * Side Effects:
    676  *	The modification time of the entire archive is also changed.
    677  *	For a library, this could necessitate the re-ranlib'ing of the
    678  *	whole thing.
    679  *
    680  *-----------------------------------------------------------------------
    681  */
    682 void
    683 Arch_Touch (gn)
    684     GNode	  *gn;	  /* Node of member to touch */
    685 {
    686     FILE *	  arch;	  /* Stream open to archive, positioned properly */
    687     struct ar_hdr arh;	  /* Current header describing member */
    688 
    689     arch = ArchFindMember(Var_Value (ARCHIVE, gn),
    690 			  Var_Value (TARGET, gn),
    691 			  &arh, "r+");
    692     sprintf(arh.ar_date, "%-12ld", (long) now);
    693 
    694     if (arch != (FILE *) NULL) {
    695 	(void)fwrite ((char *)&arh, sizeof (struct ar_hdr), 1, arch);
    696 	fclose (arch);
    697     }
    698 }
    699 
    700 /*-
    701  *-----------------------------------------------------------------------
    702  * Arch_TouchLib --
    703  *	Given a node which represents a library, touch the thing, making
    704  *	sure that the table of contents also is touched.
    705  *
    706  * Results:
    707  *	None.
    708  *
    709  * Side Effects:
    710  *	Both the modification time of the library and of the RANLIBMAG
    711  *	member are set to 'now'.
    712  *
    713  *-----------------------------------------------------------------------
    714  */
    715 void
    716 Arch_TouchLib (gn)
    717     GNode	    *gn;      	/* The node of the library to touch */
    718 {
    719     FILE *	    arch;	/* Stream open to archive */
    720     struct ar_hdr   arh;      	/* Header describing table of contents */
    721     struct timeval  times[2];	/* Times for utimes() call */
    722 
    723     arch = ArchFindMember (gn->path, RANLIBMAG, &arh, "r+");
    724     sprintf(arh.ar_date, "%-12ld", (long) now);
    725 
    726     if (arch != (FILE *) NULL) {
    727 	(void)fwrite ((char *)&arh, sizeof (struct ar_hdr), 1, arch);
    728 	fclose (arch);
    729 
    730 	times[0].tv_sec = times[1].tv_sec = now;
    731 	times[0].tv_usec = times[1].tv_usec = 0;
    732 	utimes(gn->path, times);
    733     }
    734 }
    735 
    736 /*-
    737  *-----------------------------------------------------------------------
    738  * Arch_MTime --
    739  *	Return the modification time of a member of an archive.
    740  *
    741  * Results:
    742  *	The modification time (seconds).
    743  *
    744  * Side Effects:
    745  *	The mtime field of the given node is filled in with the value
    746  *	returned by the function.
    747  *
    748  *-----------------------------------------------------------------------
    749  */
    750 int
    751 Arch_MTime (gn)
    752     GNode	  *gn;	      /* Node describing archive member */
    753 {
    754     struct ar_hdr *arhPtr;    /* Header of desired member */
    755     int		  modTime;    /* Modification time as an integer */
    756 
    757     arhPtr = ArchStatMember (Var_Value (ARCHIVE, gn),
    758 			     Var_Value (TARGET, gn),
    759 			     TRUE);
    760     if (arhPtr != (struct ar_hdr *) NULL) {
    761 	(void)sscanf (arhPtr->ar_date, "%12d", &modTime);
    762     } else {
    763 	modTime = 0;
    764     }
    765 
    766     gn->mtime = modTime;
    767     return (modTime);
    768 }
    769 
    770 /*-
    771  *-----------------------------------------------------------------------
    772  * Arch_MemMTime --
    773  *	Given a non-existent archive member's node, get its modification
    774  *	time from its archived form, if it exists.
    775  *
    776  * Results:
    777  *	The modification time.
    778  *
    779  * Side Effects:
    780  *	The mtime field is filled in.
    781  *
    782  *-----------------------------------------------------------------------
    783  */
    784 int
    785 Arch_MemMTime (gn)
    786     GNode   	  *gn;
    787 {
    788     LstNode 	  ln;
    789     GNode   	  *pgn;
    790     char    	  *nameStart,
    791 		  *nameEnd;
    792 
    793     if (Lst_Open (gn->parents) != SUCCESS) {
    794 	gn->mtime = 0;
    795 	return (0);
    796     }
    797     while ((ln = Lst_Next (gn->parents)) != NILLNODE) {
    798 	pgn = (GNode *) Lst_Datum (ln);
    799 
    800 	if (pgn->type & OP_ARCHV) {
    801 	    /*
    802 	     * If the parent is an archive specification and is being made
    803 	     * and its member's name matches the name of the node we were
    804 	     * given, record the modification time of the parent in the
    805 	     * child. We keep searching its parents in case some other
    806 	     * parent requires this child to exist...
    807 	     */
    808 	    nameStart = strchr (pgn->name, '(') + 1;
    809 	    nameEnd = strchr (nameStart, ')');
    810 
    811 	    if (pgn->make &&
    812 		strncmp(nameStart, gn->name, nameEnd - nameStart) == 0) {
    813 				     gn->mtime = Arch_MTime(pgn);
    814 	    }
    815 	} else if (pgn->make) {
    816 	    /*
    817 	     * Something which isn't a library depends on the existence of
    818 	     * this target, so it needs to exist.
    819 	     */
    820 	    gn->mtime = 0;
    821 	    break;
    822 	}
    823     }
    824 
    825     Lst_Close (gn->parents);
    826 
    827     return (gn->mtime);
    828 }
    829 
    830 /*-
    831  *-----------------------------------------------------------------------
    832  * Arch_FindLib --
    833  *	Search for a library along the given search path.
    834  *
    835  * Results:
    836  *	None.
    837  *
    838  * Side Effects:
    839  *	The node's 'path' field is set to the found path (including the
    840  *	actual file name, not -l...). If the system can handle the -L
    841  *	flag when linking (or we cannot find the library), we assume that
    842  *	the user has placed the .LIBRARIES variable in the final linking
    843  *	command (or the linker will know where to find it) and set the
    844  *	TARGET variable for this node to be the node's name. Otherwise,
    845  *	we set the TARGET variable to be the full path of the library,
    846  *	as returned by Dir_FindFile.
    847  *
    848  *-----------------------------------------------------------------------
    849  */
    850 void
    851 Arch_FindLib (gn, path)
    852     GNode	    *gn;	      /* Node of library to find */
    853     Lst	    	    path;	      /* Search path */
    854 {
    855     char	    *libName;   /* file name for archive */
    856 
    857     libName = (char *)emalloc (strlen (gn->name) + 6 - 2);
    858     sprintf(libName, "lib%s.a", &gn->name[2]);
    859 
    860     gn->path = Dir_FindFile (libName, path);
    861 
    862     free (libName);
    863 
    864 #ifdef LIBRARIES
    865     Var_Set (TARGET, gn->name, gn);
    866 #else
    867     Var_Set (TARGET, gn->path == (char *) NULL ? gn->name : gn->path, gn);
    868 #endif LIBRARIES
    869 }
    870 
    871 /*-
    872  *-----------------------------------------------------------------------
    873  * Arch_LibOODate --
    874  *	Decide if a node with the OP_LIB attribute is out-of-date. Called
    875  *	from Make_OODate to make its life easier.
    876  *
    877  *	There are several ways for a library to be out-of-date that are
    878  *	not available to ordinary files. In addition, there are ways
    879  *	that are open to regular files that are not available to
    880  *	libraries. A library that is only used as a source is never
    881  *	considered out-of-date by itself. This does not preclude the
    882  *	library's modification time from making its parent be out-of-date.
    883  *	A library will be considered out-of-date for any of these reasons,
    884  *	given that it is a target on a dependency line somewhere:
    885  *	    Its modification time is less than that of one of its
    886  *	    	  sources (gn->mtime < gn->cmtime).
    887  *	    Its modification time is greater than the time at which the
    888  *	    	  make began (i.e. it's been modified in the course
    889  *	    	  of the make, probably by archiving).
    890  *	    Its modification time doesn't agree with the modification
    891  *	    	  time of its RANLIBMAG member (i.e. its table of contents
    892  *	    	  is out-of-date).
    893  *
    894  *
    895  * Results:
    896  *	TRUE if the library is out-of-date. FALSE otherwise.
    897  *
    898  * Side Effects:
    899  *	The library will be hashed if it hasn't been already.
    900  *
    901  *-----------------------------------------------------------------------
    902  */
    903 Boolean
    904 Arch_LibOODate (gn)
    905     GNode   	  *gn;  	/* The library's graph node */
    906 {
    907     Boolean 	  oodate;
    908 
    909     if (OP_NOP(gn->type) && Lst_IsEmpty(gn->children)) {
    910 	oodate = FALSE;
    911     } else if ((gn->mtime > now) || (gn->mtime < gn->cmtime)) {
    912 	oodate = TRUE;
    913     } else {
    914 	struct ar_hdr  	*arhPtr;    /* Header for __.SYMDEF */
    915 	int 	  	modTimeTOC; /* The table-of-contents's mod time */
    916 
    917 	arhPtr = ArchStatMember (gn->path, RANLIBMAG, FALSE);
    918 
    919 	if (arhPtr != (struct ar_hdr *)NULL) {
    920 	    (void)sscanf (arhPtr->ar_date, "%12d", &modTimeTOC);
    921 
    922 	    if (DEBUG(ARCH) || DEBUG(MAKE)) {
    923 		printf("%s modified %s...", RANLIBMAG, Targ_FmtTime(modTimeTOC));
    924 	    }
    925 	    oodate = (gn->mtime > modTimeTOC);
    926 	} else {
    927 	    /*
    928 	     * A library w/o a table of contents is out-of-date
    929 	     */
    930 	    if (DEBUG(ARCH) || DEBUG(MAKE)) {
    931 		printf("No t.o.c....");
    932 	    }
    933 	    oodate = TRUE;
    934 	}
    935     }
    936     return (oodate);
    937 }
    938 
    939 /*-
    940  *-----------------------------------------------------------------------
    941  * Arch_Init --
    942  *	Initialize things for this module.
    943  *
    944  * Results:
    945  *	None.
    946  *
    947  * Side Effects:
    948  *	The 'archives' list is initialized.
    949  *
    950  *-----------------------------------------------------------------------
    951  */
    952 void
    953 Arch_Init ()
    954 {
    955     archives = Lst_Init (FALSE);
    956 }
    957