[games.git] / usr.bin / make / arch.c

/*-
 * Copyright (c) 1988, 1989, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1989 by Berkeley Softworks
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Adam de Boor.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#)arch.c   8.2 (Berkeley) 1/2/94
 * $FreeBSD: src/usr.bin/make/arch.c,v 1.48 2005/02/10 14:39:05 harti Exp $
 * $DragonFly: src/usr.bin/make/arch.c,v 1.55 2005/09/24 07:37:01 okumoto Exp $
 */

/*-
 * arch.c --
 *      Functions to manipulate libraries, archives and their members.
 *
 *      Once again, cacheing/hashing comes into play in the manipulation
 * of archives. The first time an archive is referenced, all of its members'
 * headers are read and hashed and the archive closed again. All hashed
 * archives are kept on a list which is searched each time an archive member
 * is referenced.
 *
 * The interface to this module is:
 *      Arch_ParseArchive       Given an archive specification, return a list
 *                              of GNode's, one for each member in the spec.
 *                              false is returned if the specification is
 *                              invalid for some reason.
 *
 *      Arch_Touch              Alter the modification time of the archive
 *                              member described by the given node to be
 *                              the current time.
 *
 *      Arch_TouchLib           Update the modification time of the library
 *                              described by the given node. This is special
 *                              because it also updates the modification time
 *                              of the library's table of contents.
 *
 *      Arch_MTime              Find the modification time of a member of
 *                              an archive *in the archive*. The time is also
 *                              placed in the member's GNode. Returns the
 *                              modification time.
 *
 *      Arch_MemTime            Find the modification time of a member of
 *                              an archive. Called when the member doesn't
 *                              already exist. Looks in the archive for the
 *                              modification time. Returns the modification
 *                              time.
 *
 *      Arch_FindLib            Search for a library along a path. The
 *                              library name in the GNode should be in
 *                              -l<name> format.
 *
 *      Arch_LibOODate          Special function to decide if a library node
 *                              is out-of-date.
 *
 *      Arch_Init               Initialize this module.
 */

#include <sys/param.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <ar.h>
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <regex.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <utime.h>

#include "arch.h"
#include "buf.h"
#include "config.h"
#include "dir.h"
#include "globals.h"
#include "GNode.h"
#include "hash.h"
#include "make.h"
#include "parse.h"
#include "targ.h"
#include "util.h"
#include "var.h"

typedef struct Arch {
        char            *name;          /* Name of archive */

        /*
         * All the members of the archive described
         * by <name, struct ar_hdr *> key/value pairs
         */
        Hash_Table      members;

        TAILQ_ENTRY(Arch) link;         /* link all cached archives */
} Arch;

/* Lst of archives we've already examined */
static TAILQ_HEAD(, Arch) archives = TAILQ_HEAD_INITIALIZER(archives);


/* size of the name field in the archive member header */
#define AR_NAMSIZ       sizeof(((struct ar_hdr *)0)->ar_name)

/*
 * This structure is used while reading/writing an archive
 */
struct arfile {
        FILE            *fp;            /* archive file */
        char            *fname;         /* name of the file */
        struct ar_hdr   hdr;            /* current header */
        char            sname[AR_NAMSIZ + 1]; /* short name */
        char            *member;        /* (long) member name */
        size_t          mlen;           /* size of the above */
        char            *nametab;       /* name table */
        size_t          nametablen;     /* size of the table */
        int64_t         time;           /* from ar_date */
        uint64_t        size;           /* from ar_size */
        off_t           pos;            /* header pos of current entry */
};

/*
 * Name of the symbol table. The original BSD used "__.SYMDEF". Rumours go
 * that this name may have a slash appended sometimes. Actually FreeBSD
 * uses "/" which probably came from SVR4.
 */
#define SVR4_RANLIBMAG  "/"
#define BSD_RANLIBMAG   "__.SYMDEF"

/*
 * Name of the filename table. The 4.4BSD ar format did not use this, but
 * puts long filenames directly between the member header and the object
 * file.
 */
#define SVR4_NAMEMAG    "//"
#define BSD_NAMEMAG     "ARFILENAMES/"

/*
 * 44BSD long filename key. Use a local define here instead of relying
 * on ar.h because we want this to continue working even when the
 * definition is removed from ar.h.
 */
#define BSD_EXT1        "#1/"
#define BSD_EXT1LEN     3

/* if this is true make archive errors fatal */
bool arch_fatal = true;

/**
 * ArchError
 *      An error happend while handling an archive. BSDmake traditionally
 *      ignored these errors. Now this is dependend on the global arch_fatal
 *      which, if true, makes these errors fatal and, if false, just emits an
 *      error message.
 */
#define ArchError(ARGS) do {                                    \
        if (arch_fatal)                                         \
                Fatal ARGS;                                     \
        else                                                    \
                Error ARGS;                                     \
    } while (0)

/*-
 *-----------------------------------------------------------------------
 * Arch_ParseArchive --
 *      Parse the archive specification in the given line and find/create
 *      the nodes for the specified archive members, placing their nodes
 *      on the given list, given the pointer to the start of the
 *      specification, a Lst on which to place the nodes, and a context
 *      in which to expand variables.
 *
 * Results:
 *      true if it was a valid specification. The linePtr is updated
 *      to point to the first non-space after the archive spec. The
 *      nodes for the members are placed on the given list.
 *
 * Side Effects:
 *      Some nodes may be created. The given list is extended.
 *
 *-----------------------------------------------------------------------
 */
bool
Arch_ParseArchive(char **linePtr, Lst *nodeLst, GNode *ctxt)
{
        char    *cp;            /* Pointer into line */
        GNode   *gn;            /* New node */
        char    *libName;       /* Library-part of specification */
        char    *memName;       /* Member-part of specification */
        char    *nameBuf;       /* temporary place for node name */
        char    saveChar;       /* Ending delimiter of member-name */
        bool    subLibName;     /* true if libName should have/had
                                 * variable substitution performed on it */

        libName = *linePtr;

        subLibName = false;

        for (cp = libName; *cp != OPEN_PAREN && *cp != '\0'; cp++) {
                if (*cp == '$') {
                        /*
                         * Variable spec, so call the Var module to parse the
                         * puppy so we can safely advance beyond it...
                         */
                        size_t  length = 0;
                        bool    freeIt;
                        char    *result;

                        result = Var_Parse(cp, ctxt, true, &length, &freeIt);
                        if (result == var_Error) {
                                return (false);
                        }
                        subLibName = true;

                        if (freeIt) {
                                free(result);
                        }
                        cp += length - 1;
                }
        }

        *cp++ = '\0';
        if (subLibName) {
                libName = Buf_Peel(Var_Subst(libName, ctxt, true));
        }

        for (;;) {
                /*
                 * First skip to the start of the member's name, mark that
                 * place and skip to the end of it (either white-space or
                 * a close paren).
                 */

                /*
                 * true if need to substitute in memName
                 */
                bool    doSubst = false;

                while (*cp != '\0' && *cp != CLOSE_PAREN &&
                    isspace((unsigned char)*cp)) {
                        cp++;
                }

                memName = cp;
                while (*cp != '\0' && *cp != CLOSE_PAREN &&
                    !isspace((unsigned char)*cp)) {
                        if (*cp == '$') {
                                /*
                                 * Variable spec, so call the Var module to
                                 * parse the puppy so we can safely advance
                                 * beyond it...
                                 */
                                size_t  length = 0;
                                bool    freeIt;
                                char    *result;

                                result = Var_Parse(cp, ctxt, true,
                                    &length, &freeIt);
                                if (result == var_Error) {
                                        return (false);
                                }
                                doSubst = true;

                                if (freeIt) {
                                        free(result);
                                }
                                cp += length;
                        } else {
                                cp++;
                        }
                }

                /*
                 * If the specification ends without a closing parenthesis,
                 * chances are there's something wrong (like a missing
                 * backslash), so it's better to return failure than allow
                 * such things to happen
                 */
                if (*cp == '\0') {
                        printf("No closing parenthesis in archive "
                            "specification\n");
                        return (false);
                }

                /*
                 * If we didn't move anywhere, we must be done
                 */
                if (cp == memName) {
                        break;
                }

                saveChar = *cp;
                *cp = '\0';

                /*
                 * XXX: This should be taken care of intelligently by
                 * SuffExpandChildren, both for the archive and the member
                 * portions.
                 */
                /*
                 * If member contains variables, try and substitute for them.
                 * This will slow down archive specs with dynamic sources, of
                 * course, since we'll be (non-)substituting them three times,
                 * but them's the breaks -- we need to do this since
                 * SuffExpandChildren calls us, otherwise we could assume the
                 * thing would be taken care of later.
                 */
                if (doSubst) {
                        char    *buf;
                        char    *sacrifice;
                        char    *oldMemName = memName;
                        size_t  sz;
                        Buffer  *buf1;

                        /*
                         * Now form an archive spec and recurse to deal with
                         * nested variables and multi-word variable values....
                         * The results are just placed at the end of the
                         * nodeLst we're returning.
                         */
                        buf1 = Var_Subst(memName, ctxt, true);
                        memName = Buf_Data(buf1);

                        sz = strlen(memName) + strlen(libName) + 3;
                        buf = emalloc(sz);

                        snprintf(buf, sz, "%s(%s)", libName, memName);

                        sacrifice = buf;

                        if (strchr(memName, '$') &&
                            strcmp(memName, oldMemName) == 0) {
                                /*
                                 * Must contain dynamic sources, so we can't
                                 * deal with it now.
                                 * Just create an ARCHV node for the thing and
                                 * let SuffExpandChildren handle it...
                                 */
                                gn = Targ_FindNode(buf, TARG_CREATE);

                                if (gn == NULL) {
                                        free(buf);
                                        Buf_Destroy(buf1, false);
                                        return (false);
                                }
                                gn->type |= OP_ARCHV;
                                Lst_AtEnd(nodeLst, (void *)gn);
                        } else if (!Arch_ParseArchive(&sacrifice, nodeLst,
                            ctxt)) {
                                /*
                                 * Error in nested call -- free buffer and
                                 * return false ourselves.
                                 */
                                free(buf);
                                Buf_Destroy(buf1, false);
                                return (false);
                        }

                        /* Free buffer and continue with our work. */
                        free(buf);
                        Buf_Destroy(buf1, false);

                } else if (Dir_HasWildcards(memName)) {
                        Lst     members = Lst_Initializer(members);
                        char    *member;
                        size_t  sz = MAXPATHLEN;
                        size_t  nsz;

                        nameBuf = emalloc(sz);

                        Path_Expand(memName, &dirSearchPath, &members);
                        while (!Lst_IsEmpty(&members)) {
                                member = Lst_DeQueue(&members);
                                nsz = strlen(libName) + strlen(member) + 3;
                                if (nsz > sz) {
                                        sz = nsz * 2;
                                        nameBuf = erealloc(nameBuf, sz);
                                }

                                snprintf(nameBuf, sz, "%s(%s)",
                                    libName, member);
                                free(member);
                                gn = Targ_FindNode(nameBuf, TARG_CREATE);
                                if (gn == NULL) {
                                        free(nameBuf);
                                        /* XXXHB Lst_Destroy(&members) */
                                        return (false);
                                }
                                /*
                                 * We've found the node, but have to make sure
                                 * the rest of the world knows it's an archive
                                 * member, without having to constantly check
                                 * for parentheses, so we type the thing with
                                 * the OP_ARCHV bit before we place it on the
                                 * end of the provided list.
                                 */
                                gn->type |= OP_ARCHV;
                                Lst_AtEnd(nodeLst, gn);
                        }
                        free(nameBuf);
                } else {
                        size_t  sz = strlen(libName) + strlen(memName) + 3;

                        nameBuf = emalloc(sz);
                        snprintf(nameBuf, sz, "%s(%s)", libName, memName);
                        gn = Targ_FindNode(nameBuf, TARG_CREATE);
                        free(nameBuf);
                        if (gn == NULL) {
                                return (false);
                        }
                        /*
                         * We've found the node, but have to make sure the
                         * rest of the world knows it's an archive member,
                         * without having to constantly check for parentheses,
                         * so we type the thing with the OP_ARCHV bit before
                         * we place it on the end of the provided list.
                         */
                        gn->type |= OP_ARCHV;
                        Lst_AtEnd(nodeLst, gn);
                }
                if (doSubst) {
                        free(memName);
                }

                *cp = saveChar;
        }

        /*
         * If substituted libName, free it now, since we need it no longer.
         */
        if (subLibName) {
                free(libName);
        }

        /*
         * We promised the pointer would be set up at the next non-space, so
         * we must advance cp there before setting *linePtr... (note that on
         * entrance to the loop, cp is guaranteed to point at a CLOSE_PAREN)
         */
        do {
                cp++;
        } while (*cp != '\0' && isspace((unsigned char)*cp));

        *linePtr = cp;
        return (true);
}

/*
 * Close an archive file an free all resources
 */
static void
ArchArchiveClose(struct arfile *ar)
{

        if (ar->nametab != NULL)
                free(ar->nametab);
        free(ar->member);
        if (ar->fp != NULL) {
                if (fclose(ar->fp) == EOF)
                        ArchError(("%s: close error", ar->fname));
        }
        free(ar->fname);
        free(ar);
}

/*
 * Open an archive file.
 */
static struct arfile *
ArchArchiveOpen(const char *archive, const char *mode)
{
        struct arfile *ar;
        char    magic[SARMAG];

        ar = emalloc(sizeof(*ar));
        ar->fname = estrdup(archive);
        ar->mlen = 100;
        ar->member = emalloc(ar->mlen);
        ar->nametab = NULL;
        ar->nametablen = 0;

        if ((ar->fp = fopen(ar->fname, mode)) == NULL) {
                DEBUGM(ARCH, ("%s", ar->fname));
                ArchArchiveClose(ar);
                return (NULL);
        }

        /* read MAGIC */
        if (fread(magic, SARMAG, 1, ar->fp) != 1 ||
            strncmp(magic, ARMAG, SARMAG) != 0) {
                ArchError(("%s: bad archive magic\n", ar->fname));
                ArchArchiveClose(ar);
                return (NULL);
        }

        ar->pos = 0;
        return (ar);
}

/*
 * Read the next header from the archive. The return value will be +1 if
 * the header is read successfully, 0 on EOF and -1 if an error happend.
 * On a successful return sname contains the truncated member name and
 * member the full name. hdr contains the member header. For the symbol table
 * names of length 0 are returned. The entry for the file name table is never
 * returned.
 */
static int
ArchArchiveNext(struct arfile *ar)
{
        char    *end;
        int     have_long_name;
        u_long  offs;
        char    *ptr;
        size_t  ret;
        char    buf[MAX(sizeof(ar->hdr.ar_size), sizeof(ar->hdr.ar_date)) + 1];

  next:
        /*
         * Seek to the next header.
         */
        if (ar->pos == 0) {
                ar->pos = SARMAG;
        } else {
                ar->pos += sizeof(ar->hdr) + ar->size;
                if (ar->size % 2 == 1)
                        ar->pos++;
        }

        if (fseeko(ar->fp, ar->pos, SEEK_SET) == -1) {
                ArchError(("%s: cannot seek to %jd: %s", ar->fname,
                    (intmax_t)ar->pos, strerror(errno)));
                return (-1);
        }

        /*
         * Read next member header
         */
        ret = fread(&ar->hdr, sizeof(ar->hdr), 1, ar->fp);
        if (ret != 1) {
                if (feof(ar->fp))
                        return (0);
                ArchError(("%s: error reading member header: %s", ar->fname,
                    strerror(errno)));
                return (-1);
        }
        if (strncmp(ar->hdr.ar_fmag, ARFMAG, sizeof(ar->hdr.ar_fmag)) != 0) {
                ArchError(("%s: bad entry magic", ar->fname));
                return (-1);
        }

        /*
         * looks like a member - get name by stripping trailing spaces
         * and NUL terminating.
         */
        strncpy(ar->sname, ar->hdr.ar_name, AR_NAMSIZ);
        ar->sname[AR_NAMSIZ] = '\0';
        for (ptr = ar->sname + AR_NAMSIZ; ptr > ar->sname; ptr--)
                if (ptr[-1] != ' ')
                        break;

        *ptr = '\0';

        /*
         * Parse the size. All entries need to have a size. Be careful
         * to not allow buffer overruns.
         */
        strncpy(buf, ar->hdr.ar_size, sizeof(ar->hdr.ar_size));
        buf[sizeof(ar->hdr.ar_size)] = '\0';

        errno = 0;
        ar->size = strtoumax(buf, &end, 10);
        if (errno != 0 || strspn(end, " ") != strlen(end)) {
                ArchError(("%s: bad size format in archive '%s'",
                    ar->fname, buf));
                return (-1);
        }

        /*
         * Look for the extended name table. Do this before parsing
         * the date because this table doesn't need a date.
         */
        if (strcmp(ar->sname, BSD_NAMEMAG) == 0 ||
            strcmp(ar->sname, SVR4_NAMEMAG) == 0) {
                /* filename table - read it in */
                ar->nametablen = ar->size;
                ar->nametab = emalloc(ar->nametablen);

                ret = fread(ar->nametab, 1, ar->nametablen, ar->fp);
                if (ret != ar->nametablen) {
                        if (ferror(ar->fp)) {
                                ArchError(("%s: cannot read nametab: %s",
                                    ar->fname, strerror(errno)));
                        } else {
                                ArchError(("%s: cannot read nametab: "
                                    "short read", ar->fname, strerror(errno)));
                        }
                        return (-1);
                }

                /*
                 * NUL terminate the entries. Entries are \n terminated
                 * and may have a trailing / or \.
                 */
                ptr = ar->nametab;
                while (ptr < ar->nametab + ar->nametablen) {
                        if (*ptr == '\n') {
                                if (ptr[-1] == '/' || ptr[-1] == '\\')
                                        ptr[-1] = '\0';
                                *ptr = '\0';
                        }
                        ptr++;
                }

                /* get next archive entry */
                goto next;
        }

        /*
         * Now parse the modification date. Be careful to not overrun
         * buffers.
         */
        strncpy(buf, ar->hdr.ar_date, sizeof(ar->hdr.ar_date));
        buf[sizeof(ar->hdr.ar_date)] = '\0';

        errno = 0;
        ar->time = (int64_t)strtoll(buf, &end, 10);
        if (errno != 0 || strspn(end, " ") != strlen(end)) {
                ArchError(("%s: bad date format in archive '%s'",
                    ar->fname, buf));
                return (-1);
        }

        /*
         * Now check for the symbol table. This should really be the first
         * entry, but we don't check this.
         */
        if (strcmp(ar->sname, BSD_RANLIBMAG) == 0 ||
            strcmp(ar->sname, SVR4_RANLIBMAG) == 0) {
                /* symbol table - return a zero length name */
                ar->member[0] = '\0';
                ar->sname[0] = '\0';
                return (1);
        }

        have_long_name = 0;

        /*
         * Look whether this is a long name. There are several variants
         * of long names:
         *      "#1/12          "       - 12 length of following filename
         *      "/17            "       - index into name table
         *      " 17            "       - index into name table
         * Note that in the last case we must also check that there is no
         * slash in the name because of filenames with leading spaces:
         *      " 777.o/           "    - filename 777.o
         */
        if (ar->sname[0] == '/' || (ar->sname[0] == ' ' &&
            strchr(ar->sname, '/') == NULL)) {
                /* SVR4 extended name */
                errno = 0;
                offs = strtoul(ar->sname + 1, &end, 10);
                if (errno != 0 || *end != '\0' || offs >= ar->nametablen ||
                    end == ar->sname + 1) {
                        ArchError(("%s: bad extended name '%s'", ar->fname,
                            ar->sname));
                        return (-1);
                }

                /* fetch the name */
                if (ar->mlen <= strlen(ar->nametab + offs)) {
                        ar->mlen = strlen(ar->nametab + offs) + 1;
                        ar->member = erealloc(ar->member, ar->mlen);
                }
                strcpy(ar->member, ar->nametab + offs);

                have_long_name = 1;

        } else if (strncmp(ar->sname, BSD_EXT1, BSD_EXT1LEN) == 0 &&
            isdigit((unsigned char)ar->sname[BSD_EXT1LEN])) {
                /* BSD4.4 extended name */
                errno = 0;
                offs = strtoul(ar->sname + BSD_EXT1LEN, &end, 10);
                if (errno != 0 || *end != '\0' ||
                    end == ar->sname + BSD_EXT1LEN) {
                        ArchError(("%s: bad extended name '%s'", ar->fname,
                            ar->sname));
                        return (-1);
                }

                /* read it from the archive */
                if (ar->mlen <= offs) {
                        ar->mlen = offs + 1;
                        ar->member = erealloc(ar->member, ar->mlen);
                }
                ret = fread(ar->member, 1, offs, ar->fp);
                if (ret != offs) {
                        if (ferror(ar->fp)) {
                                ArchError(("%s: reading extended name: %s",
                                    ar->fname, strerror(errno)));
                        } else {
                                ArchError(("%s: reading extended name: "
                                    "short read", ar->fname));
                        }
                        return (-1);
                }
                ar->member[offs] = '\0';

                have_long_name = 1;
        }

        /*
         * Now remove the trailing slash that Svr4 puts at
         * the end of the member name to support trailing spaces in names.
         */
        if (ptr > ar->sname && ptr[-1] == '/')
                *--ptr = '\0';

        if (!have_long_name) {
                if (strlen(ar->sname) >= ar->mlen) {
                        ar->mlen = strlen(ar->sname) + 1;
                        ar->member = erealloc(ar->member, ar->mlen);
                }
                strcpy(ar->member, ar->sname);
        }

        return (1);
}

/*
 * Touch the current archive member by writing a new header with an
 * updated timestamp. The return value is 0 for success and -1 for errors.
 */
static int
ArchArchiveTouch(struct arfile *ar, int64_t ts)
{

        /* seek to our header */
        if (fseeko(ar->fp, ar->pos, SEEK_SET) == -1) {
                ArchError(("%s: cannot seek to %jd: %s", ar->fname,
                    (intmax_t)ar->pos, strerror(errno)));
                return (-1);
        }

        /*
         * change timestamp, be sure to not NUL-terminated it, but
         * to fill with spaces.
         */
        snprintf(ar->hdr.ar_date, sizeof(ar->hdr.ar_date), "%jd",
            (intmax_t)ts);
        memset(ar->hdr.ar_date + strlen(ar->hdr.ar_date),
            ' ', sizeof(ar->hdr.ar_date) - strlen(ar->hdr.ar_date));

        if (fwrite(&ar->hdr, sizeof(ar->hdr), 1, ar->fp) != 1) {
                ArchError(("%s: cannot touch: %s", ar->fname, strerror(errno)));
                return (-1);
        }
        return (0);
}

/*-
 *-----------------------------------------------------------------------
 * ArchFindMember --
 *      Locate a member of an archive, given the path of the archive and
 *      the path of the desired member. If the archive is to be modified,
 *      the mode should be "r+", if not, it should be "r".  The archive
 *      file is returned positioned at the correct header.
 *
 * Results:
 *      A struct arfile *, opened for reading and, possibly writing,
 *      positioned at the member's header, or NULL if the member was
 *      nonexistent.
 *
 *-----------------------------------------------------------------------
 */
static struct arfile *
ArchFindMember(const char *archive, const char *member, const char *mode)
{
        struct arfile   *ar;
        const char      *cp;    /* Useful character pointer */

        if ((ar = ArchArchiveOpen(archive, mode)) == NULL)
                return (NULL);

        /*
         * Because of space constraints and similar things, files are archived
         * using their final path components, not the entire thing, so we need
         * to point 'member' to the final component, if there is one, to make
         * the comparisons easier...
         */
        if (member != NULL) {
                cp = strrchr(member, '/');
                if (cp != NULL) {
                        member = cp + 1;
                }
        }

        while (ArchArchiveNext(ar) > 0) {
                /*
                 * When comparing there are actually three cases:
                 * (1) the name fits into the limit og af_name,
                 * (2) the name is longer and the archive supports long names,
                 * (3) the name is longer and the archive doesn't support long
                 * names.
                 * Because we don't know whether the archive supports long
                 * names or not we need to be carefull.
                 */
                if (member == NULL) {
                        /* special case - symbol table */
                        if (ar->member[0] == '\0')
                                return (ar);
                } else if (strlen(member) <= AR_NAMSIZ) {
                        /* case (1) */
                        if (strcmp(ar->member, member) == 0)
                                return (ar);
                } else if (strcmp(ar->member, member) == 0) {
                        /* case (3) */
                        return (ar);
                } else {
                        /* case (2) */
                        if (strlen(ar->member) == AR_NAMSIZ &&
                            strncmp(member, ar->member, AR_NAMSIZ) == 0)
                                return (ar);
                }
        }

        /* not found */
        ArchArchiveClose(ar);
        return (NULL);
}

/*-
 *-----------------------------------------------------------------------
 * ArchStatMember --
 *      Locate a member of an archive, given the path of the archive and
 *      the path of the desired member, and a boolean representing whether
 *      or not the archive should be hashed (if not already hashed).
 *
 * Results:
 *      A pointer to the current struct ar_hdr structure for the member. Note
 *      That no position is returned, so this is not useful for touching
 *      archive members. This is mostly because we have no assurances that
 *      The archive will remain constant after we read all the headers, so
 *      there's not much point in remembering the position...
 *
 * Side Effects:
 *
 *-----------------------------------------------------------------------
 */
static int64_t
ArchStatMember(const char *archive, const char *member, bool hash)
{
        struct arfile   *arf;
        int64_t         ret;
        int             t;
        char            *cp;    /* Useful character pointer */
        Arch            *ar;    /* Archive descriptor */
        Hash_Entry      *he;    /* Entry containing member's description */
        char            copy[AR_NAMSIZ + 1];

        /*
         * Because of space constraints and similar things, files are archived
         * using their final path components, not the entire thing, so we need
         * to point 'member' to the final component, if there is one, to make
         * the comparisons easier...
         */
        if (member != NULL) {
                cp = strrchr(member, '/');
                if (cp != NULL)
                        member = cp + 1;
        }

        TAILQ_FOREACH(ar, &archives, link) {
                if (strcmp(archive, ar->name) == 0)
                        break;
        }
        if (ar == NULL) {
                /* archive not found */
                if (!hash) {
                        /*
                         * Caller doesn't want the thing hashed, just use
                         * ArchFindMember to read the header for the member
                         * out and close down the stream again.
                         */
                        arf = ArchFindMember(archive, member, "r");
                        if (arf == NULL) {
                                return (INT64_MIN);
                        }
                        ret = arf->time;
                        ArchArchiveClose(arf);
                        return (ret);
                }

                /*
                 * We don't have this archive on the list yet, so we want to
                 * find out everything that's in it and cache it so we can get
                 * at it quickly.
                 */
                arf = ArchArchiveOpen(archive, "r");
                if (arf == NULL) {
                        return (INT64_MIN);
                }

                /* create archive data structure */
                ar = emalloc(sizeof(*ar));
                ar->name = estrdup(archive);
                Hash_InitTable(&ar->members, -1);

                while ((t = ArchArchiveNext(arf)) > 0) {
                        he = Hash_CreateEntry(&ar->members, arf->member, NULL);
                        Hash_SetValue(he, emalloc(sizeof(int64_t)));
                        *(int64_t *)Hash_GetValue(he) = arf->time;
                }

                ArchArchiveClose(arf);

                if (t < 0) {
                        /* error happend - throw away everything */
                        Hash_DeleteTable(&ar->members);
                        free(ar->name);
                        free(ar);
                        return (INT64_MIN);
                }

                TAILQ_INSERT_TAIL(&archives, ar, link);
        }

        /*
         * Now that the archive has been read and cached, we can look into
         * the hash table to find the desired member's header.
         */
        he = Hash_FindEntry(&ar->members, member);
        if (he != NULL)
                return (*(int64_t *)Hash_GetValue(he));

        if (member != NULL && strlen(member) > AR_NAMSIZ) {
                /* Try truncated name */
                strncpy(copy, member, AR_NAMSIZ);
                copy[AR_NAMSIZ] = '\0';

                if ((he = Hash_FindEntry(&ar->members, copy)) != NULL)
                        return (*(int64_t *)Hash_GetValue(he));
        }

        return (INT64_MIN);
}

/*-
 *-----------------------------------------------------------------------
 * Arch_Touch --
 *      Touch a member of an archive.
 *
 * Results:
 *      The 'time' field of the member's header is updated.
 *
 * Side Effects:
 *      The modification time of the entire archive is also changed.
 *      For a library, this could necessitate the re-ranlib'ing of the
 *      whole thing.
 *
 *-----------------------------------------------------------------------
 */
void
Arch_Touch(GNode *gn)
{
        struct arfile   *ar;

        ar = ArchFindMember(
            Var_Value(ARCHIVE, gn), Var_Value(TARGET, gn), "r+");

        if (ar != NULL) {
                ArchArchiveTouch(ar, (int64_t)now);
                ArchArchiveClose(ar);
        }
}

/*-
 *-----------------------------------------------------------------------
 * Arch_TouchLib --
 *      Given a node which represents a library, touch the thing, making
 *      sure that the table of contents also is touched.
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      Both the modification time of the library and of the RANLIBMAG
 *      member are set to 'now'.
 *
 *-----------------------------------------------------------------------
 */
void
Arch_TouchLib(GNode *gn)
{
        struct arfile   *ar;    /* Open archive */
        struct utimbuf  times;  /* Times for utime() call */

        ar = ArchFindMember(gn->path, NULL, "r+");
        if (ar != NULL) {
                ArchArchiveTouch(ar, (int64_t)now);
                ArchArchiveClose(ar);

                times.actime = times.modtime = now;
                utime(gn->path, &times);
        }
}

/*-
 *-----------------------------------------------------------------------
 * Arch_MTime --
 *      Return the modification time of a member of an archive, given its
 *      name.
 *
 * Results:
 *      The modification time(seconds).
 *      XXXHB this should be a long.
 *
 * Side Effects:
 *      The mtime field of the given node is filled in with the value
 *      returned by the function.
 *
 *-----------------------------------------------------------------------
 */
int
Arch_MTime(GNode *gn)
{
        int64_t mtime;

        mtime = ArchStatMember(
            Var_Value(ARCHIVE, gn), Var_Value(TARGET, gn), true);

        if (mtime == INT_MIN) {
                mtime = 0;
        }
        gn->mtime = (int)mtime;                 /* XXX */
        return (gn->mtime);
}

/*-
 *-----------------------------------------------------------------------
 * Arch_MemMTime --
 *      Given a non-existent archive member's node, get its modification
 *      time from its archived form, if it exists.
 *
 * Results:
 *      The modification time.
 *
 * Side Effects:
 *      The mtime field is filled in.
 *
 *-----------------------------------------------------------------------
 */
int
Arch_MemMTime(GNode *gn)
{
        LstNode *ln;
        GNode   *pgn;
        char    *nameStart;
        char    *nameEnd;

        for (ln = Lst_First(&gn->parents); ln != NULL; ln = Lst_Succ(ln)) {
                pgn = Lst_Datum(ln);

                if (pgn->type & OP_ARCHV) {
                        /*
                         * If the parent is an archive specification and is
                         * being made and its member's name matches the name of
                         * the node we were given, record the modification time
                         * of the parent in the child. We keep searching its
                         * parents in case some other parent requires this
                         * child to exist...
                         */
                        nameStart = strchr(pgn->name, OPEN_PAREN) + 1;
                        nameEnd = strchr(nameStart, CLOSE_PAREN);

                        if (pgn->make && strncmp(nameStart, gn->name,
                            nameEnd - nameStart) == 0) {
                                gn->mtime = Arch_MTime(pgn);
                        }
                } else if (pgn->make) {
                        /*
                         * Something which isn't a library depends on the
                         * existence of this target, so it needs to exist.
                         */
                        gn->mtime = 0;
                        break;
                }
        }
        return (gn->mtime);
}

/*-
 *-----------------------------------------------------------------------
 * Arch_FindLib --
 *      Search for a named library along the given search path.
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      The node's 'path' field is set to the found path (including the
 *      actual file name, not -l...). If the system can handle the -L
 *      flag when linking (or we cannot find the library), we assume that
 *      the user has placed the .LIBRARIES variable in the final linking
 *      command (or the linker will know where to find it) and set the
 *      TARGET variable for this node to be the node's name. Otherwise,
 *      we set the TARGET variable to be the full path of the library,
 *      as returned by Dir_FindFile.
 *
 *-----------------------------------------------------------------------
 */
void
Arch_FindLib(GNode *gn, struct Path *path)
{
        char    *libName;       /* file name for archive */
        size_t  sz;

        sz = strlen(gn->name) + 4;
        libName = emalloc(sz);
        snprintf(libName, sz, "lib%s.a", &gn->name[2]);

        gn->path = Path_FindFile(libName, path);

        free(libName);

#ifdef LIBRARIES
        Var_Set(TARGET, gn->name, gn);
#else
        Var_Set(TARGET, gn->path == NULL ? gn->name : gn->path, gn);
#endif /* LIBRARIES */
}

/*-
 *-----------------------------------------------------------------------
 * Arch_LibOODate --
 *      Decide if a node with the OP_LIB attribute is out-of-date. Called
 *      from Make_OODate to make its life easier, with the library's
 *      graph node.
 *
 *      There are several ways for a library to be out-of-date that are
 *      not available to ordinary files. In addition, there are ways
 *      that are open to regular files that are not available to
 *      libraries. A library that is only used as a source is never
 *      considered out-of-date by itself. This does not preclude the
 *      library's modification time from making its parent be out-of-date.
 *      A library will be considered out-of-date for any of these reasons,
 *      given that it is a target on a dependency line somewhere:
 *          Its modification time is less than that of one of its
 *                sources (gn->mtime < gn->cmtime).
 *          Its modification time is greater than the time at which the
 *                make began (i.e. it's been modified in the course
 *                of the make, probably by archiving).
 *          The modification time of one of its sources is greater than
 *                the one of its RANLIBMAG member (i.e. its table of contents
 *                is out-of-date). We don't compare of the archive time
 *                vs. TOC time because they can be too close. In my
 *                opinion we should not bother with the TOC at all since
 *                this is used by 'ar' rules that affect the data contents
 *                of the archive, not by ranlib rules, which affect the
 *                TOC.
 *
 * Results:
 *      true if the library is out-of-date. false otherwise.
 *
 * Side Effects:
 *      The library will be hashed if it hasn't been already.
 *
 *-----------------------------------------------------------------------
 */
bool
Arch_LibOODate(GNode *gn)
{
        int64_t mtime;  /* The table-of-contents's mod time */

        if (OP_NOP(gn->type) && Lst_IsEmpty(&gn->children)) {
                return (false);
        }
        if (gn->mtime > now || gn->mtime < gn->cmtime) {
                return (true);
        }

        mtime = ArchStatMember(gn->path, NULL, false);
        if (mtime == INT64_MIN) {
                /*
                 * Not found. A library w/o a table of contents is out-of-date
                 */
                if (DEBUG(ARCH) || DEBUG(MAKE)) {
                        Debug("No TOC...");
                }
                return (true);
        }

        /* XXX choose one. */
        if (DEBUG(ARCH) || DEBUG(MAKE)) {
                Debug("TOC modified %s...", Targ_FmtTime(mtime));
        }
        return (gn->cmtime > mtime);
}