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arch.c revision 1.1
      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 static char sccsid[] = "@(#)arch.c	5.7 (Berkeley) 12/28/90";
     41 #endif /* not lint */
     42 
     43 /*-
     44  * arch.c --
     45  *	Functions to manipulate libraries, archives and their members.
     46  *
     47  *	Once again, cacheing/hashing comes into play in the manipulation
     48  * of archives. The first time an archive is referenced, all of its members'
     49  * headers are read and hashed and the archive closed again. All hashed
     50  * archives are kept on a list which is searched each time an archive member
     51  * is referenced.
     52  *
     53  * The interface to this module is:
     54  *	Arch_ParseArchive   	Given an archive specification, return a list
     55  *	    	  	    	of GNode's, one for each member in the spec.
     56  *	    	  	    	FAILURE is returned if the specification is
     57  *	    	  	    	invalid for some reason.
     58  *
     59  *	Arch_Touch	    	Alter the modification time of the archive
     60  *	    	  	    	member described by the given node to be
     61  *	    	  	    	the current time.
     62  *
     63  *	Arch_TouchLib	    	Update the modification time of the library
     64  *	    	  	    	described by the given node. This is special
     65  *	    	  	    	because it also updates the modification time
     66  *	    	  	    	of the library's table of contents.
     67  *
     68  *	Arch_MTime	    	Find the modification time of a member of
     69  *	    	  	    	an archive *in the archive*. The time is also
     70  *	    	  	    	placed in the member's GNode. Returns the
     71  *	    	  	    	modification time.
     72  *
     73  *	Arch_MemTime	    	Find the modification time of a member of
     74  *	    	  	    	an archive. Called when the member doesn't
     75  *	    	  	    	already exist. Looks in the archive for the
     76  *	    	  	    	modification time. Returns the modification
     77  *	    	  	    	time.
     78  *
     79  *	Arch_FindLib	    	Search for a library along a path. The
     80  *	    	  	    	library name in the GNode should be in
     81  *	    	  	    	-l<name> format.
     82  *
     83  *	Arch_LibOODate	    	Special function to decide if a library node
     84  *	    	  	    	is out-of-date.
     85  *
     86  *	Arch_Init 	    	Initialize this module.
     87  */
     88 
     89 #include    <sys/types.h>
     90 #include    <sys/stat.h>
     91 #include    <sys/time.h>
     92 #include    <ctype.h>
     93 #include    <ar.h>
     94 #include <ranlib.h>
     95 #include    <stdio.h>
     96 #include    "make.h"
     97 #include    "hash.h"
     98 
     99 static Lst	  archives;   /* Lst of archives we've already examined */
    100 
    101 typedef struct Arch {
    102     char	  *name;      /* Name of archive */
    103     Hash_Table	  members;    /* All the members of the archive described
    104 			       * by <name, struct ar_hdr *> key/value pairs */
    105 } Arch;
    106 
    107 static FILE *ArchFindMember();
    108 
    109 /*-
    110  *-----------------------------------------------------------------------
    111  * Arch_ParseArchive --
    112  *	Parse the archive specification in the given line and find/create
    113  *	the nodes for the specified archive members, placing their nodes
    114  *	on the given list.
    115  *
    116  * Results:
    117  *	SUCCESS if it was a valid specification. The linePtr is updated
    118  *	to point to the first non-space after the archive spec. The
    119  *	nodes for the members are placed on the given list.
    120  *
    121  * Side Effects:
    122  *	Some nodes may be created. The given list is extended.
    123  *
    124  *-----------------------------------------------------------------------
    125  */
    126 ReturnStatus
    127 Arch_ParseArchive (linePtr, nodeLst, ctxt)
    128     char	    **linePtr;      /* Pointer to start of specification */
    129     Lst	    	    nodeLst;   	    /* Lst on which to place the nodes */
    130     GNode   	    *ctxt;  	    /* Context in which to expand variables */
    131 {
    132     register char   *cp;	    /* Pointer into line */
    133     GNode	    *gn;     	    /* New node */
    134     char	    *libName;  	    /* Library-part of specification */
    135     char	    *memName;  	    /* Member-part of specification */
    136     char	    nameBuf[BSIZE]; /* temporary place for node name */
    137     char	    saveChar;  	    /* Ending delimiter of member-name */
    138     Boolean 	    subLibName;	    /* TRUE if libName should have/had
    139 				     * variable substitution performed on it */
    140 
    141     libName = *linePtr;
    142 
    143     subLibName = FALSE;
    144 
    145     for (cp = libName; *cp != '(' && *cp != '\0'; cp++) {
    146 	if (*cp == '$') {
    147 	    /*
    148 	     * Variable spec, so call the Var module to parse the puppy
    149 	     * so we can safely advance beyond it...
    150 	     */
    151 	    int 	length;
    152 	    Boolean	freeIt;
    153 	    char	*result;
    154 
    155 	    result=Var_Parse(cp, ctxt, TRUE, &length, &freeIt);
    156 	    if (result == var_Error) {
    157 		return(FAILURE);
    158 	    } else {
    159 		subLibName = TRUE;
    160 	    }
    161 
    162 	    if (freeIt) {
    163 		free(result);
    164 	    }
    165 	    cp += length-1;
    166 	}
    167     }
    168 
    169     *cp++ = '\0';
    170     if (subLibName) {
    171 	libName = Var_Subst(libName, ctxt, TRUE);
    172     }
    173 
    174 
    175     while (1) {
    176 	/*
    177 	 * First skip to the start of the member's name, mark that
    178 	 * place and skip to the end of it (either white-space or
    179 	 * a close paren).
    180 	 */
    181 	Boolean	doSubst = FALSE; /* TRUE if need to substitute in memName */
    182 
    183 	while (*cp != '\0' && *cp != ')' && isspace (*cp)) {
    184 	    cp++;
    185 	}
    186 	memName = cp;
    187 	while (*cp != '\0' && *cp != ')' && !isspace (*cp)) {
    188 	    if (*cp == '$') {
    189 		/*
    190 		 * Variable spec, so call the Var module to parse the puppy
    191 		 * so we can safely advance beyond it...
    192 		 */
    193 		int 	length;
    194 		Boolean	freeIt;
    195 		char	*result;
    196 
    197 		result=Var_Parse(cp, ctxt, TRUE, &length, &freeIt);
    198 		if (result == var_Error) {
    199 		    return(FAILURE);
    200 		} else {
    201 		    doSubst = TRUE;
    202 		}
    203 
    204 		if (freeIt) {
    205 		    free(result);
    206 		}
    207 		cp += length;
    208 	    } else {
    209 		cp++;
    210 	    }
    211 	}
    212 
    213 	/*
    214 	 * If the specification ends without a closing parenthesis,
    215 	 * chances are there's something wrong (like a missing backslash),
    216 	 * so it's better to return failure than allow such things to happen
    217 	 */
    218 	if (*cp == '\0') {
    219 	    printf("No closing parenthesis in archive specification\n");
    220 	    return (FAILURE);
    221 	}
    222 
    223 	/*
    224 	 * If we didn't move anywhere, we must be done
    225 	 */
    226 	if (cp == memName) {
    227 	    break;
    228 	}
    229 
    230 	saveChar = *cp;
    231 	*cp = '\0';
    232 
    233 	/*
    234 	 * XXX: This should be taken care of intelligently by
    235 	 * SuffExpandChildren, both for the archive and the member portions.
    236 	 */
    237 	/*
    238 	 * If member contains variables, try and substitute for them.
    239 	 * This will slow down archive specs with dynamic sources, of course,
    240 	 * since we'll be (non-)substituting them three times, but them's
    241 	 * the breaks -- we need to do this since SuffExpandChildren calls
    242 	 * us, otherwise we could assume the thing would be taken care of
    243 	 * later.
    244 	 */
    245 	if (doSubst) {
    246 	    char    *buf;
    247 	    char    *sacrifice;
    248 	    char    *oldMemName = memName;
    249 
    250 	    memName = Var_Subst(memName, ctxt, TRUE);
    251 
    252 	    /*
    253 	     * Now form an archive spec and recurse to deal with nested
    254 	     * variables and multi-word variable values.... The results
    255 	     * are just placed at the end of the nodeLst we're returning.
    256 	     */
    257 	    buf = sacrifice = emalloc(strlen(memName)+strlen(libName)+3);
    258 
    259 	    sprintf(buf, "%s(%s)", libName, memName);
    260 
    261 	    if (index(memName, '$') && strcmp(memName, oldMemName) == 0) {
    262 		/*
    263 		 * Must contain dynamic sources, so we can't deal with it now.
    264 		 * Just create an ARCHV node for the thing and let
    265 		 * SuffExpandChildren handle it...
    266 		 */
    267 		gn = Targ_FindNode(buf, TARG_CREATE);
    268 
    269 		if (gn == NILGNODE) {
    270 		    free(buf);
    271 		    return(FAILURE);
    272 		} else {
    273 		    gn->type |= OP_ARCHV;
    274 		    (void)Lst_AtEnd(nodeLst, (ClientData)gn);
    275 		}
    276 	    } else if (Arch_ParseArchive(&sacrifice, nodeLst, ctxt)!=SUCCESS) {
    277 		/*
    278 		 * Error in nested call -- free buffer and return FAILURE
    279 		 * ourselves.
    280 		 */
    281 		free(buf);
    282 		return(FAILURE);
    283 	    }
    284 	    /*
    285 	     * Free buffer and continue with our work.
    286 	     */
    287 	    free(buf);
    288 	} else if (Dir_HasWildcards(memName)) {
    289 	    Lst	  members = Lst_Init(FALSE);
    290 	    char  *member;
    291 
    292 	    Dir_Expand(memName, dirSearchPath, members);
    293 	    while (!Lst_IsEmpty(members)) {
    294 		member = (char *)Lst_DeQueue(members);
    295 
    296 		sprintf(nameBuf, "%s(%s)", libName, member);
    297 		free(member);
    298 		gn = Targ_FindNode (nameBuf, TARG_CREATE);
    299 		if (gn == NILGNODE) {
    300 		    return (FAILURE);
    301 		} else {
    302 		    /*
    303 		     * We've found the node, but have to make sure the rest of
    304 		     * the world knows it's an archive member, without having
    305 		     * to constantly check for parentheses, so we type the
    306 		     * thing with the OP_ARCHV bit before we place it on the
    307 		     * end of the provided list.
    308 		     */
    309 		    gn->type |= OP_ARCHV;
    310 		    (void) Lst_AtEnd (nodeLst, (ClientData)gn);
    311 		}
    312 	    }
    313 	    Lst_Destroy(members, NOFREE);
    314 	} else {
    315 	    sprintf(nameBuf, "%s(%s)", libName, memName);
    316 	    gn = Targ_FindNode (nameBuf, TARG_CREATE);
    317 	    if (gn == NILGNODE) {
    318 		return (FAILURE);
    319 	    } else {
    320 		/*
    321 		 * We've found the node, but have to make sure the rest of the
    322 		 * world knows it's an archive member, without having to
    323 		 * constantly check for parentheses, so we type the thing with
    324 		 * the OP_ARCHV bit before we place it on the end of the
    325 		 * provided list.
    326 		 */
    327 		gn->type |= OP_ARCHV;
    328 		(void) Lst_AtEnd (nodeLst, (ClientData)gn);
    329 	    }
    330 	}
    331 	if (doSubst) {
    332 	    free(memName);
    333 	}
    334 
    335 	*cp = saveChar;
    336     }
    337 
    338     /*
    339      * If substituted libName, free it now, since we need it no longer.
    340      */
    341     if (subLibName) {
    342 	free(libName);
    343     }
    344 
    345     /*
    346      * We promised the pointer would be set up at the next non-space, so
    347      * we must advance cp there before setting *linePtr... (note that on
    348      * entrance to the loop, cp is guaranteed to point at a ')')
    349      */
    350     do {
    351 	cp++;
    352     } while (*cp != '\0' && isspace (*cp));
    353 
    354     *linePtr = cp;
    355     return (SUCCESS);
    356 }
    357 
    358 /*-
    359  *-----------------------------------------------------------------------
    360  * ArchFindArchive --
    361  *	See if the given archive is the one we are looking for. Called
    362  *	From ArchStatMember and ArchFindMember via Lst_Find.
    363  *
    364  * Results:
    365  *	0 if it is, non-zero if it isn't.
    366  *
    367  * Side Effects:
    368  *	None.
    369  *
    370  *-----------------------------------------------------------------------
    371  */
    372 static int
    373 ArchFindArchive (ar, archName)
    374     Arch	  *ar;	      	  /* Current list element */
    375     char	  *archName;  	  /* Name we want */
    376 {
    377     return (strcmp (archName, ar->name));
    378 }
    379 
    380 /*-
    381  *-----------------------------------------------------------------------
    382  * ArchStatMember --
    383  *	Locate a member of an archive, given the path of the archive and
    384  *	the path of the desired member.
    385  *
    386  * Results:
    387  *	A pointer to the current struct ar_hdr structure for the member. Note
    388  *	That no position is returned, so this is not useful for touching
    389  *	archive members. This is mostly because we have no assurances that
    390  *	The archive will remain constant after we read all the headers, so
    391  *	there's not much point in remembering the position...
    392  *
    393  * Side Effects:
    394  *
    395  *-----------------------------------------------------------------------
    396  */
    397 static struct ar_hdr *
    398 ArchStatMember (archive, member, hash)
    399     char	  *archive;   /* Path to the archive */
    400     char	  *member;    /* Name of member. If it is a path, only the
    401 			       * last component is used. */
    402     Boolean	  hash;	      /* TRUE if archive should be hashed if not
    403     			       * already so. */
    404 {
    405 #define AR_MAX_NAME_LEN	    (sizeof(arh.ar_name)-1)
    406     FILE *	  arch;	      /* Stream to archive */
    407     int		  size;       /* Size of archive member */
    408     char	  *cp;	      /* Useful character pointer */
    409     char	  magic[SARMAG];
    410     int		  len;
    411     LstNode	  ln;	      /* Lst member containing archive descriptor */
    412     Arch	  *ar;	      /* Archive descriptor */
    413     Hash_Entry	  *he;	      /* Entry containing member's description */
    414     struct ar_hdr arh;        /* archive-member header for reading archive */
    415     char	  memName[AR_MAX_NAME_LEN+1];
    416     	    	    	    /* Current member name while hashing. The name is
    417 			     * truncated to AR_MAX_NAME_LEN bytes, but we need
    418 			     * room for the null byte... */
    419     char    	  copy[AR_MAX_NAME_LEN+1];
    420     	    	    	    /* Holds copy of last path element from member, if
    421 			     * it has to be truncated, so we don't have to
    422 			     * figure it out again once the table is hashed. */
    423 
    424     /*
    425      * Because of space constraints and similar things, files are archived
    426      * using their final path components, not the entire thing, so we need
    427      * to point 'member' to the final component, if there is one, to make
    428      * the comparisons easier...
    429      */
    430     cp = rindex (member, '/');
    431     if (cp != (char *) NULL) {
    432 	member = cp + 1;
    433     }
    434     len = strlen (member);
    435     if (len > AR_MAX_NAME_LEN) {
    436 	len = AR_MAX_NAME_LEN;
    437 	strncpy(copy, member, AR_MAX_NAME_LEN);
    438 	copy[AR_MAX_NAME_LEN] = '\0';
    439 	member = copy;
    440     }
    441 
    442     ln = Lst_Find (archives, (ClientData) archive, ArchFindArchive);
    443     if (ln != NILLNODE) {
    444 	ar = (Arch *) Lst_Datum (ln);
    445 
    446 	he = Hash_FindEntry (&ar->members, member);
    447 
    448 	if (he != (Hash_Entry *) NULL) {
    449 	    return ((struct ar_hdr *) Hash_GetValue (he));
    450 	} else {
    451 	    return ((struct ar_hdr *) NULL);
    452 	}
    453     }
    454 
    455     if (!hash) {
    456 	/*
    457 	 * Caller doesn't want the thing hashed, just use ArchFindMember
    458 	 * to read the header for the member out and close down the stream
    459 	 * again. Since the archive is not to be hashed, we assume there's
    460 	 * no need to allocate extra room for the header we're returning,
    461 	 * so just declare it static.
    462 	 */
    463 	 static struct ar_hdr	sarh;
    464 
    465 	 arch = ArchFindMember(archive, member, &sarh, "r");
    466 
    467 	 if (arch == (FILE *)NULL) {
    468 	    return ((struct ar_hdr *)NULL);
    469 	} else {
    470 	    fclose(arch);
    471 	    return (&sarh);
    472 	}
    473     }
    474 
    475     /*
    476      * We don't have this archive on the list yet, so we want to find out
    477      * everything that's in it and cache it so we can get at it quickly.
    478      */
    479     arch = fopen (archive, "r");
    480     if (arch == (FILE *) NULL) {
    481 	return ((struct ar_hdr *) NULL);
    482     }
    483 
    484     /*
    485      * We use the ARMAG string to make sure this is an archive we
    486      * can handle...
    487      */
    488     if ((fread (magic, SARMAG, 1, arch) != 1) ||
    489     	(strncmp (magic, ARMAG, SARMAG) != 0)) {
    490 	    fclose (arch);
    491 	    return ((struct ar_hdr *) NULL);
    492     }
    493 
    494     ar = (Arch *)emalloc (sizeof (Arch));
    495     ar->name = strdup (archive);
    496     Hash_InitTable (&ar->members, -1);
    497     memName[AR_MAX_NAME_LEN] = '\0';
    498 
    499     while (fread ((char *)&arh, sizeof (struct ar_hdr), 1, arch) == 1) {
    500 	if (strncmp ( arh.ar_fmag, ARFMAG, sizeof (arh.ar_fmag)) != 0) {
    501 				 /*
    502 				  * The header is bogus, so the archive is bad
    503 				  * and there's no way we can recover...
    504 				  */
    505 				 fclose (arch);
    506 				 Hash_DeleteTable (&ar->members);
    507 				 free ((Address)ar);
    508 				 return ((struct ar_hdr *) NULL);
    509 	} else {
    510 	    (void) strncpy (memName, arh.ar_name, sizeof(arh.ar_name));
    511 	    for (cp = &memName[AR_MAX_NAME_LEN]; *cp == ' '; cp--) {
    512 		continue;
    513 	    }
    514 	    cp[1] = '\0';
    515 
    516 	    he = Hash_CreateEntry (&ar->members, strdup (memName),
    517 				   (Boolean *)NULL);
    518 	    Hash_SetValue (he, (ClientData)emalloc (sizeof (struct ar_hdr)));
    519 	    bcopy ((Address)&arh, (Address)Hash_GetValue (he),
    520 		sizeof (struct ar_hdr));
    521 	}
    522 	/*
    523 	 * We need to advance the stream's pointer to the start of the
    524 	 * next header. Files are padded with newlines to an even-byte
    525 	 * boundary, so we need to extract the size of the file from the
    526 	 * 'size' field of the header and round it up during the seek.
    527 	 */
    528 	arh.ar_size[sizeof(arh.ar_size)-1] = '\0';
    529 	(void) sscanf (arh.ar_size, "%10d", &size);
    530 	fseek (arch, (size + 1) & ~1, 1);
    531     }
    532 
    533     fclose (arch);
    534 
    535     (void) Lst_AtEnd (archives, (ClientData) ar);
    536 
    537     /*
    538      * Now that the archive has been read and cached, we can look into
    539      * the hash table to find the desired member's header.
    540      */
    541     he = Hash_FindEntry (&ar->members, member);
    542 
    543     if (he != (Hash_Entry *) NULL) {
    544 	return ((struct ar_hdr *) Hash_GetValue (he));
    545     } else {
    546 	return ((struct ar_hdr *) NULL);
    547     }
    548 }
    549 
    550 /*-
    551  *-----------------------------------------------------------------------
    552  * ArchFindMember --
    553  *	Locate a member of an archive, given the path of the archive and
    554  *	the path of the desired member. If the archive is to be modified,
    555  *	the mode should be "r+", if not, it should be "r".
    556  *
    557  * Results:
    558  *	An FILE *, opened for reading and writing, positioned at the
    559  *	start of the member's struct ar_hdr, or NULL if the member was
    560  *	nonexistent. The current struct ar_hdr for member.
    561  *
    562  * Side Effects:
    563  *	The passed struct ar_hdr structure is filled in.
    564  *
    565  *-----------------------------------------------------------------------
    566  */
    567 static FILE *
    568 ArchFindMember (archive, member, arhPtr, mode)
    569     char	  *archive;   /* Path to the archive */
    570     char	  *member;    /* Name of member. If it is a path, only the
    571 			       * last component is used. */
    572     struct ar_hdr *arhPtr;    /* Pointer to header structure to be filled in */
    573     char	  *mode;      /* The mode for opening the stream */
    574 {
    575     FILE *	  arch;	      /* Stream to archive */
    576     int		  size;       /* Size of archive member */
    577     char	  *cp;	      /* Useful character pointer */
    578     char	  magic[SARMAG];
    579     int		  len;
    580 
    581     arch = fopen (archive, mode);
    582     if (arch == (FILE *) NULL) {
    583 	return ((FILE *) NULL);
    584     }
    585 
    586     /*
    587      * We use the ARMAG string to make sure this is an archive we
    588      * can handle...
    589      */
    590     if ((fread (magic, SARMAG, 1, arch) != 1) ||
    591     	(strncmp (magic, ARMAG, SARMAG) != 0)) {
    592 	    fclose (arch);
    593 	    return ((FILE *) NULL);
    594     }
    595 
    596     /*
    597      * Because of space constraints and similar things, files are archived
    598      * using their final path components, not the entire thing, so we need
    599      * to point 'member' to the final component, if there is one, to make
    600      * the comparisons easier...
    601      */
    602     cp = rindex (member, '/');
    603     if (cp != (char *) NULL) {
    604 	member = cp + 1;
    605     }
    606     len = strlen (member);
    607     if (len > sizeof (arhPtr->ar_name)) {
    608 	len = sizeof (arhPtr->ar_name);
    609     }
    610 
    611     while (fread ((char *)arhPtr, sizeof (struct ar_hdr), 1, arch) == 1) {
    612 	if (strncmp(arhPtr->ar_fmag, ARFMAG, sizeof (arhPtr->ar_fmag) ) != 0) {
    613 	     /*
    614 	      * The header is bogus, so the archive is bad
    615 	      * and there's no way we can recover...
    616 	      */
    617 	     fclose (arch);
    618 	     return ((FILE *) NULL);
    619 	} else if (strncmp (member, arhPtr->ar_name, len) == 0) {
    620 	    /*
    621 	     * If the member's name doesn't take up the entire 'name' field,
    622 	     * we have to be careful of matching prefixes. Names are space-
    623 	     * padded to the right, so if the character in 'name' at the end
    624 	     * of the matched string is anything but a space, this isn't the
    625 	     * member we sought.
    626 	     */
    627 	    if (len != sizeof(arhPtr->ar_name) && arhPtr->ar_name[len] != ' '){
    628 		continue;
    629 	    } else {
    630 		/*
    631 		 * To make life easier, we reposition the file at the start
    632 		 * of the header we just read before we return the stream.
    633 		 * In a more general situation, it might be better to leave
    634 		 * the file at the actual member, rather than its header, but
    635 		 * not here...
    636 		 */
    637 		fseek (arch, -sizeof(struct ar_hdr), 1);
    638 		return (arch);
    639 	    }
    640 	} else {
    641 	    /*
    642 	     * This isn't the member we're after, so we need to advance the
    643 	     * stream's pointer to the start of the next header. Files are
    644 	     * padded with newlines to an even-byte boundary, so we need to
    645 	     * extract the size of the file from the 'size' field of the
    646 	     * header and round it up during the seek.
    647 	     */
    648 	    arhPtr->ar_size[sizeof(arhPtr->ar_size)-1] = '\0';
    649 	    (void)sscanf (arhPtr->ar_size, "%10d", &size);
    650 	    fseek (arch, (size + 1) & ~1, 1);
    651 	}
    652     }
    653 
    654     /*
    655      * We've looked everywhere, but the member is not to be found. Close the
    656      * archive and return NULL -- an error.
    657      */
    658     fclose (arch);
    659     return ((FILE *) NULL);
    660 }
    661 
    662 /*-
    663  *-----------------------------------------------------------------------
    664  * Arch_Touch --
    665  *	Touch a member of an archive.
    666  *
    667  * Results:
    668  *	The 'time' field of the member's header is updated.
    669  *
    670  * Side Effects:
    671  *	The modification time of the entire archive is also changed.
    672  *	For a library, this could necessitate the re-ranlib'ing of the
    673  *	whole thing.
    674  *
    675  *-----------------------------------------------------------------------
    676  */
    677 void
    678 Arch_Touch (gn)
    679     GNode	  *gn;	  /* Node of member to touch */
    680 {
    681     FILE *	  arch;	  /* Stream open to archive, positioned properly */
    682     struct ar_hdr arh;	  /* Current header describing member */
    683 
    684     arch = ArchFindMember(Var_Value (ARCHIVE, gn),
    685 			  Var_Value (TARGET, gn),
    686 			  &arh, "r+");
    687     sprintf(arh.ar_date, "%-12d", now);
    688 
    689     if (arch != (FILE *) NULL) {
    690 	(void)fwrite ((char *)&arh, sizeof (struct ar_hdr), 1, arch);
    691 	fclose (arch);
    692     }
    693 }
    694 
    695 /*-
    696  *-----------------------------------------------------------------------
    697  * Arch_TouchLib --
    698  *	Given a node which represents a library, touch the thing, making
    699  *	sure that the table of contents also is touched.
    700  *
    701  * Results:
    702  *	None.
    703  *
    704  * Side Effects:
    705  *	Both the modification time of the library and of the RANLIBMAG
    706  *	member are set to 'now'.
    707  *
    708  *-----------------------------------------------------------------------
    709  */
    710 void
    711 Arch_TouchLib (gn)
    712     GNode	    *gn;      	/* The node of the library to touch */
    713 {
    714     FILE *	    arch;	/* Stream open to archive */
    715     struct ar_hdr   arh;      	/* Header describing table of contents */
    716     struct timeval  times[2];	/* Times for utimes() call */
    717 
    718     arch = ArchFindMember (gn->path, RANLIBMAG, &arh, "r+");
    719     sprintf(arh.ar_date, "%-12d", now);
    720 
    721     if (arch != (FILE *) NULL) {
    722 	(void)fwrite ((char *)&arh, sizeof (struct ar_hdr), 1, arch);
    723 	fclose (arch);
    724 
    725 	times[0].tv_sec = times[1].tv_sec = now;
    726 	times[0].tv_usec = times[1].tv_usec = 0;
    727 	utimes(gn->path, times);
    728     }
    729 }
    730 
    731 /*-
    732  *-----------------------------------------------------------------------
    733  * Arch_MTime --
    734  *	Return the modification time of a member of an archive.
    735  *
    736  * Results:
    737  *	The modification time (seconds).
    738  *
    739  * Side Effects:
    740  *	The mtime field of the given node is filled in with the value
    741  *	returned by the function.
    742  *
    743  *-----------------------------------------------------------------------
    744  */
    745 int
    746 Arch_MTime (gn)
    747     GNode	  *gn;	      /* Node describing archive member */
    748 {
    749     struct ar_hdr *arhPtr;    /* Header of desired member */
    750     int		  modTime;    /* Modification time as an integer */
    751 
    752     arhPtr = ArchStatMember (Var_Value (ARCHIVE, gn),
    753 			     Var_Value (TARGET, gn),
    754 			     TRUE);
    755     if (arhPtr != (struct ar_hdr *) NULL) {
    756 	(void)sscanf (arhPtr->ar_date, "%12d", &modTime);
    757     } else {
    758 	modTime = 0;
    759     }
    760 
    761     gn->mtime = modTime;
    762     return (modTime);
    763 }
    764 
    765 /*-
    766  *-----------------------------------------------------------------------
    767  * Arch_MemMTime --
    768  *	Given a non-existent archive member's node, get its modification
    769  *	time from its archived form, if it exists.
    770  *
    771  * Results:
    772  *	The modification time.
    773  *
    774  * Side Effects:
    775  *	The mtime field is filled in.
    776  *
    777  *-----------------------------------------------------------------------
    778  */
    779 int
    780 Arch_MemMTime (gn)
    781     GNode   	  *gn;
    782 {
    783     LstNode 	  ln;
    784     GNode   	  *pgn;
    785     char    	  *nameStart,
    786 		  *nameEnd;
    787 
    788     if (Lst_Open (gn->parents) != SUCCESS) {
    789 	gn->mtime = 0;
    790 	return (0);
    791     }
    792     while ((ln = Lst_Next (gn->parents)) != NILLNODE) {
    793 	pgn = (GNode *) Lst_Datum (ln);
    794 
    795 	if (pgn->type & OP_ARCHV) {
    796 	    /*
    797 	     * If the parent is an archive specification and is being made
    798 	     * and its member's name matches the name of the node we were
    799 	     * given, record the modification time of the parent in the
    800 	     * child. We keep searching its parents in case some other
    801 	     * parent requires this child to exist...
    802 	     */
    803 	    nameStart = index (pgn->name, '(') + 1;
    804 	    nameEnd = index (nameStart, ')');
    805 
    806 	    if (pgn->make &&
    807 		strncmp(nameStart, gn->name, nameEnd - nameStart) == 0) {
    808 				     gn->mtime = Arch_MTime(pgn);
    809 	    }
    810 	} else if (pgn->make) {
    811 	    /*
    812 	     * Something which isn't a library depends on the existence of
    813 	     * this target, so it needs to exist.
    814 	     */
    815 	    gn->mtime = 0;
    816 	    break;
    817 	}
    818     }
    819 
    820     Lst_Close (gn->parents);
    821 
    822     return (gn->mtime);
    823 }
    824 
    825 /*-
    826  *-----------------------------------------------------------------------
    827  * Arch_FindLib --
    828  *	Search for a library along the given search path.
    829  *
    830  * Results:
    831  *	None.
    832  *
    833  * Side Effects:
    834  *	The node's 'path' field is set to the found path (including the
    835  *	actual file name, not -l...). If the system can handle the -L
    836  *	flag when linking (or we cannot find the library), we assume that
    837  *	the user has placed the .LIBRARIES variable in the final linking
    838  *	command (or the linker will know where to find it) and set the
    839  *	TARGET variable for this node to be the node's name. Otherwise,
    840  *	we set the TARGET variable to be the full path of the library,
    841  *	as returned by Dir_FindFile.
    842  *
    843  *-----------------------------------------------------------------------
    844  */
    845 void
    846 Arch_FindLib (gn, path)
    847     GNode	    *gn;	      /* Node of library to find */
    848     Lst	    	    path;	      /* Search path */
    849 {
    850     char	    *libName;   /* file name for archive */
    851 
    852     libName = (char *)emalloc (strlen (gn->name) + 6 - 2);
    853     sprintf(libName, "lib%s.a", &gn->name[2]);
    854 
    855     gn->path = Dir_FindFile (libName, path);
    856 
    857     free (libName);
    858 
    859 #ifdef LIBRARIES
    860     Var_Set (TARGET, gn->name, gn);
    861 #else
    862     Var_Set (TARGET, gn->path == (char *) NULL ? gn->name : gn->path, gn);
    863 #endif LIBRARIES
    864 }
    865 
    866 /*-
    867  *-----------------------------------------------------------------------
    868  * Arch_LibOODate --
    869  *	Decide if a node with the OP_LIB attribute is out-of-date. Called
    870  *	from Make_OODate to make its life easier.
    871  *
    872  *	There are several ways for a library to be out-of-date that are
    873  *	not available to ordinary files. In addition, there are ways
    874  *	that are open to regular files that are not available to
    875  *	libraries. A library that is only used as a source is never
    876  *	considered out-of-date by itself. This does not preclude the
    877  *	library's modification time from making its parent be out-of-date.
    878  *	A library will be considered out-of-date for any of these reasons,
    879  *	given that it is a target on a dependency line somewhere:
    880  *	    Its modification time is less than that of one of its
    881  *	    	  sources (gn->mtime < gn->cmtime).
    882  *	    Its modification time is greater than the time at which the
    883  *	    	  make began (i.e. it's been modified in the course
    884  *	    	  of the make, probably by archiving).
    885  *	    Its modification time doesn't agree with the modification
    886  *	    	  time of its RANLIBMAG member (i.e. its table of contents
    887  *	    	  is out-of-date).
    888  *
    889  *
    890  * Results:
    891  *	TRUE if the library is out-of-date. FALSE otherwise.
    892  *
    893  * Side Effects:
    894  *	The library will be hashed if it hasn't been already.
    895  *
    896  *-----------------------------------------------------------------------
    897  */
    898 Boolean
    899 Arch_LibOODate (gn)
    900     GNode   	  *gn;  	/* The library's graph node */
    901 {
    902     Boolean 	  oodate;
    903 
    904     if (OP_NOP(gn->type) && Lst_IsEmpty(gn->children)) {
    905 	oodate = FALSE;
    906     } else if ((gn->mtime > now) || (gn->mtime < gn->cmtime)) {
    907 	oodate = TRUE;
    908     } else {
    909 	struct ar_hdr  	*arhPtr;    /* Header for __.SYMDEF */
    910 	int 	  	modTimeTOC; /* The table-of-contents's mod time */
    911 
    912 	arhPtr = ArchStatMember (gn->path, RANLIBMAG, FALSE);
    913 
    914 	if (arhPtr != (struct ar_hdr *)NULL) {
    915 	    (void)sscanf (arhPtr->ar_date, "%12d", &modTimeTOC);
    916 
    917 	    if (DEBUG(ARCH) || DEBUG(MAKE)) {
    918 		printf("%s modified %s...", RANLIBMAG, Targ_FmtTime(modTimeTOC));
    919 	    }
    920 	    oodate = (gn->mtime > modTimeTOC);
    921 	} else {
    922 	    /*
    923 	     * A library w/o a table of contents is out-of-date
    924 	     */
    925 	    if (DEBUG(ARCH) || DEBUG(MAKE)) {
    926 		printf("No t.o.c....");
    927 	    }
    928 	    oodate = TRUE;
    929 	}
    930     }
    931     return (oodate);
    932 }
    933 
    934 /*-
    935  *-----------------------------------------------------------------------
    936  * Arch_Init --
    937  *	Initialize things for this module.
    938  *
    939  * Results:
    940  *	None.
    941  *
    942  * Side Effects:
    943  *	The 'archives' list is initialized.
    944  *
    945  *-----------------------------------------------------------------------
    946  */
    947 void
    948 Arch_Init ()
    949 {
    950     archives = Lst_Init (FALSE);
    951 }
    952