1626 libld may accidentally return success while failing

[unleashed.git] / usr / src / cmd / sgs / libld / common / libs.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 *      Copyright (c) 1988 AT&T
 *        All Rights Reserved
 *
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Library processing
 */
#include        <stdio.h>
#include        <string.h>
#include        <errno.h>
#include        <ar.h>
#include        <debug.h>
#include        "msg.h"
#include        "_libld.h"

/*
 * Archive members are typically extracted to resolve an existing undefined
 * reference.  However, other symbol definitions can cause archive members to
 * be processed to determine if the archive member provides a more appropriate
 * definition.  This routine processes the archive member to determine if the
 * member is really required.
 *
 *  i.  Tentative symbols may cause the extraction of an archive member.
 *      If the archive member has a strong defined symbol it will be used.
 *      If the archive member simply contains another tentative definition,
 *      or a defined function symbol, then it will not be used.
 *
 *  ii. A symbol reference may define a hidden or protected visibility.  The
 *      reference can only be bound to a definition within a relocatable object
 *      for this restricted visibility to be satisfied.  If the archive member
 *      provides a definition of the same symbol type, this definition is
 *      taken.  The visibility of the defined symbol is irrelevant, as the most
 *      restrictive visibility of the reference and the definition will be
 *      applied to the final symbol.
 *
 * exit:
 *      Returns 1 if there is a match, 0 if no match is seen, and S_ERROR if an
 *      error occurred.
 */
static uintptr_t
process_member(Ar_mem *amp, const char *name, Sym_desc *sdp, Ofl_desc *ofl)
{
        Sym     *syms, *osym = sdp->sd_sym;
        Xword   symn, cnt;
        char    *strs;

        /*
         * Find the first symbol table in the archive member, obtain its
         * data buffer and determine the number of global symbols (Note,
         * there must be a symbol table present otherwise the archive would
         * never have been able to generate its own symbol entry for this
         * member).
         */
        if (amp->am_syms == NULL) {
                Elf_Scn         *scn = NULL;
                Shdr            *shdr;
                Elf_Data        *data;

                while (scn = elf_nextscn(amp->am_elf, scn)) {
                        if ((shdr = elf_getshdr(scn)) == NULL) {
                                ld_eprintf(ofl, ERR_ELF,
                                    MSG_INTL(MSG_ELF_GETSHDR), amp->am_path);
                                return (S_ERROR);
                        }
                        if ((shdr->sh_type == SHT_SYMTAB) ||
                            (shdr->sh_type == SHT_DYNSYM))
                                break;
                }
                if ((data = elf_getdata(scn, NULL)) == NULL) {
                        ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETDATA),
                            amp->am_path);
                        return (S_ERROR);
                }
                syms = (Sym *)data->d_buf;
                syms += shdr->sh_info;
                symn = shdr->sh_size / shdr->sh_entsize;
                symn -= shdr->sh_info;

                /*
                 * Get the data for the associated string table.
                 */
                if ((scn = elf_getscn(amp->am_elf, (size_t)shdr->sh_link)) ==
                    NULL) {
                        ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETSCN),
                            amp->am_path);
                        return (S_ERROR);
                }
                if ((data = elf_getdata(scn, NULL)) == NULL) {
                        ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETDATA),
                            amp->am_path);
                        return (S_ERROR);
                }
                strs = data->d_buf;

                /*
                 * Initialize the archive member structure in case we have to
                 * come through here again.
                 */
                amp->am_syms = syms;
                amp->am_strs = strs;
                amp->am_symn = symn;
        } else {
                syms = amp->am_syms;
                strs = amp->am_strs;
                symn = amp->am_symn;
        }

        /*
         * Loop through the symbol table entries looking for a match for the
         * original symbol.
         */
        for (cnt = 0; cnt < symn; syms++, cnt++) {
                Word    shndx;

                if ((shndx = syms->st_shndx) == SHN_UNDEF)
                        continue;

                if (osym->st_shndx == SHN_COMMON) {
                        /*
                         * Determine whether a tentative symbol definition
                         * should be overridden.
                         */
                        if ((shndx == SHN_ABS) || (shndx == SHN_COMMON) ||
                            (ELF_ST_TYPE(syms->st_info) == STT_FUNC))
                                continue;

                        /*
                         * A historic detail requires that a weak definition
                         * within an archive will not override a strong
                         * definition (see sym_realtent() resolution and ABI
                         * symbol binding description - page 4-27).
                         */
                        if ((ELF_ST_BIND(syms->st_info) == STB_WEAK) &&
                            (ELF_ST_BIND(osym->st_info) != STB_WEAK))
                                continue;
                } else {
                        /*
                         * Determine whether a restricted visibility reference
                         * should be overridden.  Don't worry about the
                         * visibility of the archive member definition, nor
                         * whether it is weak or global.  Any definition is
                         * better than a binding to an external shared object
                         * (which is the only event that must presently exist
                         * for us to be here looking for a better alternative).
                         */
                        if (ELF_ST_TYPE(syms->st_info) !=
                            ELF_ST_TYPE(osym->st_info))
                                continue;
                }

                if (strcmp(strs + syms->st_name, name) == 0)
                        return (1);
        }
        return (0);
}

/*
 * Create an archive descriptor.  By maintaining a list of archives any
 * duplicate occurrences of the same archive specified by the user enable us to
 * pick off where the last processing finished.
 */
Ar_desc *
ld_ar_setup(const char *name, Elf *elf, Ofl_desc *ofl)
{
        Ar_desc *       adp;
        size_t          number;
        Elf_Arsym *     start;

        /*
         * Unless, -z allextract is specified, get the archive symbol table
         * if one exists, and ignore the file with a warning message otherwise.
         */
        if (ofl->ofl_flags1 & FLG_OF1_ALLEXRT) {
                start = NULL;
        } else  if ((start = elf_getarsym(elf, &number)) == NULL) {
                if (elf_errno())
                        ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETARSYM),
                            name);
                else
                        ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_ELF_ARSYM),
                            name);
                return (0);
        }

        /*
         * As this is a new archive reference establish a new descriptor.
         */
        if ((adp = libld_malloc(sizeof (Ar_desc))) == NULL)
                return ((Ar_desc *)S_ERROR);
        adp->ad_name = name;
        adp->ad_elf = elf;
        adp->ad_start = start;
        if (start) {
                adp->ad_aux = libld_calloc(sizeof (Ar_aux), number);
                if (adp->ad_aux == NULL)
                        return ((Ar_desc *)S_ERROR);
        } else {
                adp->ad_aux = NULL;
        }

        /*
         * Retain any command line options that are applicable to archive
         * extraction in case we have to rescan this archive later.
         */
        adp->ad_flags = ofl->ofl_flags1 & MSK_OF1_ARCHIVE;

        ofl->ofl_arscnt++;

        /*
         * Add this new descriptor to the list of archives.
         */
        if (aplist_append(&ofl->ofl_ars, adp, AL_CNT_OFL_LIBS) == NULL)
                return ((Ar_desc *)S_ERROR);
        else
                return (adp);
}

/*
 * For each archive descriptor, maintain an `Ar_aux' table to parallel the
 * archive symbol table (returned from elf_getarsym(3e)).  Use this table to
 * hold a `Sym_desc' for each symbol (thus reducing the number of
 * ld_sym_find()'s), and to hold the `Ar_mem' pointer.  The `Ar_mem' element
 * can have one of three values indicating the state of the archive member
 * associated with the offset for this symbol table entry:
 *
 *  0           indicates that the member has not been processed.
 *
 *  FLG_ARMEM_PROC
 *              indicates that the member has been processed.
 *
 *  addr        indicates that the member has been investigated to determine if
 *              it contained a symbol definition we need, but was found not to
 *              be a candidate for extraction.  In this case the members
 *              structure is maintained for possible later use.
 *
 * Each time we process an archive member we use its offset value to scan this
 * `Ar_aux' list.  If the member has been extracted, each entry with the same
 * offset has its `Ar_mem' pointer set to FLG_ARMEM_PROC.  Thus if we cycle back
 * through the archive symbol table we will ignore these symbols as they will
 * have already been added to the output image.  If a member has been processed
 * but found not to contain a symbol we need, each entry with the same offset
 * has its `Ar_mem' pointer set to the member structures address.
 */
void
ld_ar_member(Ar_desc * adp, Elf_Arsym * arsym, Ar_aux * aup, Ar_mem * amp)
{
        Elf_Arsym *     _arsym = arsym;
        Ar_aux *        _aup = aup;
        size_t          _off = arsym->as_off;

        if (adp->ad_start == NULL)
                return;

        /*
         * Note: This algorithm assumes that the archive symbol table is
         * built from the member objects, in the same order as those
         * members are found in the archive. As such, the symbols for a
         * given member will all cluster together. If this is not true,
         * we will fail to mark some symbols. In that case, archive
         * processing may be less efficient than it would be otherwise.
         */

        if (_arsym != adp->ad_start) {
                do {
                        _arsym--;
                        _aup--;
                        if (_arsym->as_off != _off)
                                break;
                        _aup->au_mem = amp;
                } while (_arsym != adp->ad_start);
        }

        _arsym = arsym;
        _aup = aup;

        do {
                if (_arsym->as_off != _off)
                        break;
                _aup->au_mem = amp;
                _arsym++;
                _aup++;
        } while (_arsym->as_name);
}

/*
 * Return the archive member's name.
 *
 * entry:
 *      name - Name of archive
 *      arelf - ELF descriptor for archive member.
 *      ofl - output descriptor
 *
 * exit:
 *      Returns pointer to archive member name on success, NULL on error.
 */
static const char *
ar_member_name(const char *name, Elf *arelf, Ofl_desc *ofl)
{
        Elf_Arhdr       *arhdr;

        if ((arhdr = elf_getarhdr(arelf)) == NULL) {
                ld_eprintf(ofl, ERR_ELF, MSG_INTL(MSG_ELF_GETARHDR), name);
                return (NULL);
        }
        return (arhdr->ar_name);
}

/*
 * Construct the member's full pathname, using the format "%s(%s)".
 *
 * entry:
 *      name - Name of archive
 *      arname - Name of archive member
 *      ofl - output descriptor
 * exit:
 *      Returns pointer to constructed pathname on success, NULL on error.
 */
static const char *
ar_member_path(const char *name, const char *arname, Ofl_desc *ofl)
{
        size_t          len;
        char            *path;

        len = strlen(name) + strlen(arname) + 3;
        if ((path = libld_malloc(len)) == NULL) {
                ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_SYS_MALLOC),
                    strerror(errno));
                return (NULL);
        }
        (void) snprintf(path, len, MSG_ORIG(MSG_FMT_ARMEM), name, arname);
        return (path);
}

/*
 * Input the specified archive member to the link.
 *
 * entry:
 *      fd - Open file descriptor for archive
 *      adp - Archive descriptor
 *      ofl - output descriptor
 *      arelf - ELF descriptor for archive member.
 *      arpath - Address of pointer to be set to constructed path name
 *              for object.
 *      rej - Rejection descriptor to pass to ld_process_ifl().
 *
 * exit:
 *      This routine can return one of the following:
 *      S_ERROR:  Fatal error encountered.
 *      0: Object was rejected, and should be ignored.
 *              rej will carry the rejection information.
 *      1: The archive member has been input to the link.
 */
static uintptr_t
ar_input(int fd, Ar_desc *adp, Ofl_desc *ofl, Elf *arelf,
    const char *arpath, Rej_desc *rej)
{
        Rej_desc        _rej = { 0 };

        switch (ld_process_ifl(arpath, NULL, fd, arelf,
            (FLG_IF_EXTRACT | FLG_IF_NEEDED), ofl, &_rej, NULL)) {
        case S_ERROR:
                return (S_ERROR);
        case 0:
                /*
                 * If this member is rejected maintain the first rejection
                 * error for possible later display.
                 */
                if (_rej.rej_type) {
                        if (rej->rej_type == 0) {
                                rej->rej_type = _rej.rej_type;
                                rej->rej_info = _rej.rej_info;
                                rej->rej_name = arpath;
                        }
                        (void) elf_end(arelf);
                        return (0);
                }
        }

        /*
         * Indicate that the extracted member is in use.  This
         * enables debugging diags, and indicates that a further
         * rescan of all archives may be necessary.
         */
        ofl->ofl_flags1 |= FLG_OF1_EXTRACT;
        adp->ad_flags |= FLG_ARD_EXTRACT;
        return (1);
}

/*
 * Data structure to indicate whether a symbol is visible for the purpose
 * of archive extraction.
 */
static const Boolean
sym_vis[STV_NUM] = {
        TRUE,           /* STV_DEFAULT */
        FALSE,          /* STV_INTERNAL */
        FALSE,          /* STV_HIDDEN */
        FALSE,          /* STV_PROTECTED */
        TRUE,           /* STV_EXPORTED */
        TRUE,           /* STV_SINGLETON */
        FALSE           /* STV_ELIMINATE */
};
#if STV_NUM != (STV_ELIMINATE + 1)
#error "STV_NUM has grown. Update sym_vis[]."
#endif

/*
 * Read the archive symbol table.  For each symbol in the table, determine
 * whether that symbol satisfies an unresolved reference, tentative reference,
 * or a reference that expects hidden or protected visibility.  If so, the
 * corresponding object from the archive is processed.  The archive symbol
 * table is searched until we go through a complete pass without satisfying any
 * unresolved symbols
 *
 * entry:
 *      name - Name of archive
 *      fd - Open file descriptor for archive
 *      adp - Archive descriptor
 *      ofl - output descriptor
 *      found - Address of variable to set to TRUE if any objects are extracted
 *      rej - Rejection descriptor to pass to ld_process_ifl().
 *
 * exit:
 *      Returns FALSE on fatal error. On success, *found will be TRUE
 *      if any object was extracted, rej will be set if any object
 *      was rejected, and TRUE is returned.
 */
static Boolean
ar_extract_bysym(const char *name, int fd, Ar_desc *adp,
    Ofl_desc *ofl, Boolean *found, Rej_desc *rej)
{
        Elf_Arsym *     arsym;
        Elf *           arelf;
        Ar_aux *        aup;
        Sym_desc *      sdp;
        const char      *arname, *arpath;
        Boolean         again = FALSE;
        uintptr_t       err;

        /*
         * An archive without a symbol table should not reach this function,
         * because it can only get past ld_ar_setup() in the case where
         * the archive is first seen under the influence of '-z allextract'.
         * That will cause the entire archive to be extracted, and any
         * subsequent reference to the archive will be ignored by
         * ld_process_archive().
         */
        if (adp->ad_start == NULL) {
                assert(adp->ad_start != NULL);
                return (TRUE);
        }

        /*
         * Loop through archive symbol table until we make a complete pass
         * without satisfying an unresolved reference.  For each archive
         * symbol, see if there is a symbol with the same name in ld's
         * symbol table.  If so, and if that symbol is still unresolved or
         * tentative, process the corresponding archive member.
         */
        do {
                DBG_CALL(Dbg_file_ar(ofl->ofl_lml, name, again));
                DBG_CALL(Dbg_syms_ar_title(ofl->ofl_lml, name, again));
                again = FALSE;

                for (arsym = adp->ad_start, aup = adp->ad_aux; arsym->as_name;
                    ++arsym, ++aup) {
                        Ar_mem          *amp;
                        Sym             *sym;
                        Boolean         visible = TRUE;
                        Boolean         vers;
                        Ifl_desc        *ifl;

                        /*
                         * If the auxiliary members value indicates that this
                         * member has been processed then this symbol will have
                         * been added to the output file image already or the
                         * object was rejected in which case we don't want to
                         * process it again.
                         */
                        if (aup->au_mem == FLG_ARMEM_PROC)
                                continue;

                        /*
                         * If the auxiliary symbol element is non-zero lookup
                         * the symbol from the internal symbol table.
                         */
                        if ((sdp = aup->au_syms) == NULL) {
                                if ((sdp = ld_sym_find(arsym->as_name,
                                    /* LINTED */
                                    (Word)arsym->as_hash, NULL, ofl)) == NULL) {
                                        DBG_CALL(Dbg_syms_ar_skip(ofl->ofl_lml,
                                            name, arsym));
                                        continue;
                                }
                                aup->au_syms = sdp;
                        }

                        /*
                         * With '-z allextract', all members will be extracted.
                         *
                         * This archive member is a candidate for extraction if
                         * the internal symbol originates from an explicit file,
                         * and represents an undefined or tentative symbol.
                         *
                         * By default, weak references do not cause archive
                         * extraction, however the -zweakextract flag overrides
                         * this default.
                         *
                         * If this symbol has already been bound to a versioned
                         * shared object, but the shared objects version is not
                         * available, then a definition of this symbol from
                         * within the archive is a better candidate.  Similarly,
                         * if this symbol has been bound to a shared object, but
                         * the original reference expected hidden or protected
                         * visibility, then a definition of this symbol from
                         * within the archive is a better candidate.
                         */
                        vers = TRUE;
                        ifl = sdp->sd_file;

                        sym = sdp->sd_sym;

                        if (sdp->sd_ref == REF_DYN_NEED) {
                                uchar_t vis;

                                if (ifl->ifl_vercnt) {
                                        Word            vndx;
                                        Ver_index       *vip;

                                        vndx = sdp->sd_aux->sa_dverndx;
                                        vip = &ifl->ifl_verndx[vndx];
                                        if (!(vip->vi_flags & FLG_VER_AVAIL))
                                                vers = FALSE;
                                }

                                vis = ELF_ST_VISIBILITY(sym->st_other);
                                visible = sym_vis[vis];
                        }

                        if (((ifl->ifl_flags & FLG_IF_NEEDED) == 0) ||
                            (visible && vers && (sym->st_shndx != SHN_UNDEF) &&
                            (sym->st_shndx != SHN_COMMON)) ||
                            ((ELF_ST_BIND(sym->st_info) == STB_WEAK) &&
                            (!(ofl->ofl_flags1 & FLG_OF1_WEAKEXT)))) {
                                DBG_CALL(Dbg_syms_ar_skip(ofl->ofl_lml,
                                    name, arsym));
                                continue;
                        }

                        /*
                         * Determine if we have already extracted this member,
                         * and if so reuse the Ar_mem information.
                         */
                        if ((amp = aup->au_mem) != 0) {
                                arelf = amp->am_elf;
                                arname = amp->am_name;
                                arpath = amp->am_path;
                        } else {
                                /*
                                 * Set up a new elf descriptor for this member.
                                 */
                                if (elf_rand(adp->ad_elf, arsym->as_off) !=
                                    arsym->as_off) {
                                        ld_eprintf(ofl, ERR_ELF,
                                            MSG_INTL(MSG_ELF_ARMEM), name,
                                            EC_WORD(arsym->as_off),
                                            demangle(arsym->as_name));
                                        return (FALSE);
                                }

                                if ((arelf = elf_begin(fd, ELF_C_READ,
                                    adp->ad_elf)) == NULL) {
                                        ld_eprintf(ofl, ERR_ELF,
                                            MSG_INTL(MSG_ELF_BEGIN), name);
                                        return (FALSE);
                                }

                                /* Get member filename */
                                if ((arname = ar_member_name(name, arelf,
                                    ofl)) == NULL)
                                        return (FALSE);

                                /* Construct the member's full pathname */
                                if ((arpath = ar_member_path(name, arname,
                                    ofl)) == NULL)
                                        return (FALSE);

                                /*
                                 * Determine whether the support libraries wish
                                 * to process this open. See comments in
                                 * ld_process_open().
                                 */
                                ld_sup_open(ofl, &arpath, &arname, &fd,
                                    (FLG_IF_EXTRACT | FLG_IF_NEEDED),
                                    &arelf, adp->ad_elf, arsym->as_off,
                                    elf_kind(arelf));
                                if (arelf == NULL) {
                                        /* Ignore this archive member */
                                        aup->au_mem = FLG_ARMEM_PROC;
                                        continue;
                                }
                        }

                        /*
                         * The symbol for which this archive member is being
                         * processed may provide a better alternative to the
                         * symbol that is presently known.  Two cases are
                         * covered:
                         *
                         *  i.  The present symbol represents tentative data.
                         *      The archive member may provide a data
                         *      definition symbol.
                         *  ii. The present symbol represents a reference that
                         *      has seen a definition within a shared object
                         *      dependency, but the reference expects to be
                         *      reduced to hidden or protected visibility.
                         */
                        if ((sym->st_shndx == SHN_COMMON) ||
                            (visible == FALSE)) {
                                /*
                                 * If we don't already have a member structure
                                 * allocate one.
                                 */
                                if (!amp) {
                                        if ((amp = libld_calloc(sizeof (Ar_mem),
                                            1)) == NULL)
                                                return (FALSE);
                                        amp->am_elf = arelf;
                                        amp->am_name = arname;
                                        amp->am_path = arpath;
                                }
                                DBG_CALL(Dbg_syms_ar_checking(ofl->ofl_lml,
                                    name, arname, arsym));
                                if ((err = process_member(amp, arsym->as_name,
                                    sdp, ofl)) == S_ERROR)
                                        return (FALSE);

                                /*
                                 * If it turns out that we don't need this
                                 * member simply initialize all other auxiliary
                                 * entries that match this offset with this
                                 * members address.  In this way we can resuse
                                 * this information if we recurse back to this
                                 * symbol.
                                 */
                                if (err == 0) {
                                        if (aup->au_mem == NULL)
                                                ld_ar_member(adp, arsym,
                                                    aup, amp);
                                        continue;
                                }
                        }

                        /*
                         * Process the archive member.  Retain any error for
                         * return to the caller.
                         */
                        DBG_CALL(Dbg_syms_ar_resolve(ofl->ofl_lml,
                            name, arname, arsym));
                        switch (ar_input(fd, adp, ofl, arelf, arpath,
                            rej)) {
                        case S_ERROR:
                                return (FALSE);
                        case 0:
                                /*
                                 * Mark the member as extracted so that we
                                 * don't try and process it again on a rescan.
                                 */
                                ld_ar_member(adp, arsym, aup, FLG_ARMEM_PROC);
                                continue;
                        }

                        /*
                         * Note that this archive has contributed something
                         * during this specific operation, and also signal
                         * the need to rescan the archive.
                         */
                        *found = again = TRUE;

                        ld_ar_member(adp, arsym, aup, FLG_ARMEM_PROC);
                }
        } while (again);

        return (TRUE);
}


/*
 * Extract every object in the given archive directly without going through
 * the symbol table.
 *
 * entry:
 *      name - Name of archive
 *      fd - Open file descriptor for archive
 *      adp - Archive descriptor
 *      ofl - output descriptor
 *      found - Address of variable to set to TRUE if any objects are extracted
 *      rej - Rejection descriptor to pass to ld_process_ifl().
 *
 * exit:
 *      Returns FALSE on fatal error. On success, *found will be TRUE
 *      if any object was extracted, rej will be set if any object
 *      was rejected, and TRUE is returned.
 */
static Boolean
ar_extract_all(const char *name, int fd, Ar_desc *adp, Ofl_desc *ofl,
    Boolean *found, Rej_desc *rej)
{
        Elf_Cmd         cmd = ELF_C_READ;
        Elf             *arelf;
        const char      *arname, *arpath;
        size_t          off, next_off;

        DBG_CALL(Dbg_file_ar(ofl->ofl_lml, name, FALSE));

        while ((arelf = elf_begin(fd, cmd, adp->ad_elf)) != NULL) {
                /*
                 * Call elf_next() so that the next call to elf_begin() will
                 * fetch the archive member following this one. We do this now
                 * because it simplifies the logic below, and because the
                 * support libraries called below can set our handle to NULL.
                 */
                cmd = elf_next(arelf);

                /* Get member filename */
                if ((arname = ar_member_name(name, arelf, ofl)) == NULL)
                        return (FALSE);

                /*
                 * Skip the symbol table, string table, or any other special
                 * archive member. These all start with a '/' character.
                 */
                if (*arname == '/') {
                        (void) elf_end(arelf);
                        continue;
                }

                /* Obtain archive member offset within the file */
                off = _elf_getarhdrbase(arelf);

                /*
                 * ld_sup_open() will reset the current iteration point for
                 * the archive to point at this member rather than the next
                 * one for the benefit of the support libraries. Since
                 * this loop relies on the current position not changing
                 * underneath it, we save and restore the current
                 * position around the support library call.
                 */
                next_off = _elf_getnextoff(adp->ad_elf);

                /* Construct the member's full pathname */
                if ((arpath = ar_member_path(name, arname, ofl)) == NULL)
                        return (FALSE);

                /*
                 * Determine whether the support libraries wish to process
                 * this open. See comments in ld_process_open().
                 */
                ld_sup_open(ofl, &arpath, &arname, &fd,
                    (FLG_IF_EXTRACT | FLG_IF_NEEDED), &arelf, adp->ad_elf,
                    off, elf_kind(arelf));
                (void) elf_rand(adp->ad_elf, next_off);
                if (arelf == NULL)
                        continue;

                DBG_CALL(Dbg_syms_ar_force(ofl->ofl_lml, name, arname));
                switch (ar_input(fd, adp, ofl, arelf, arpath, rej)) {
                case S_ERROR:
                        return (FALSE);
                case 0:
                        continue;
                }

                *found = TRUE;

        }

        /*
         * As this archive was extracted by -z allextract, the ar_aux table
         * and elf descriptor can be freed.  Set ad_elf to NULL to mark the
         * archive is completely processed.
         */
        (void) elf_end(adp->ad_elf);
        adp->ad_elf = NULL;

        return (TRUE);
}


/*
 * Process the given archive and extract objects for inclusion into
 * the link.
 *
 * entry:
 *      name - Name of archive
 *      fd - Open file descriptor for archive
 *      adp - Archive descriptor
 *      ofl - output descriptor
 *
 * exit:
 *      Returns FALSE on fatal error, TRUE otherwise.
 */
Boolean
ld_process_archive(const char *name, int fd, Ar_desc *adp, Ofl_desc *ofl)
{
        Boolean         found = FALSE;
        Rej_desc        rej = { 0 };

        /*
         * If a fatal error condition has been set there's really no point in
         * processing the archive further.  Having got to this point we have at
         * least established that the archive exists (thus verifying that the
         * command line options that got us to this archive are correct).  Very
         * large archives can take a significant time to process, therefore
         * continuing on from here may significantly delay the fatal error
         * message the user is already set to receive.
         */
        if (ofl->ofl_flags & FLG_OF_FATAL)
                return (TRUE);

        /*
         * If this archive was processed with -z allextract, then all members
         * have already been extracted.
         */
        if (adp->ad_elf == NULL)
                return (TRUE);

        if (ofl->ofl_flags1 & FLG_OF1_ALLEXRT) {
                if (!ar_extract_all(name, fd, adp, ofl, &found, &rej))
                        return (FALSE);
        } else {
                if (!ar_extract_bysym(name, fd, adp, ofl, &found, &rej))
                        return (FALSE);
        }

        /*
         * If no objects have been found in the archive test for any rejections
         * and if one had occurred issue a warning - its possible a user has
         * pointed at an archive containing the wrong class of elf members.
         */
        if ((found == 0) && rej.rej_type) {
                Conv_reject_desc_buf_t rej_buf;

                ld_eprintf(ofl, ERR_WARNING, MSG_INTL(reject[rej.rej_type]),
                    rej.rej_name ? rej.rej_name : MSG_INTL(MSG_STR_UNKNOWN),
                    conv_reject_desc(&rej, &rej_buf, ld_targ.t_m.m_mach));
        }


        return (TRUE);
}