trans.c

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/*
 *  trans.c
 *
 *  Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.org>
 *  Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
 *  Copyright (c) 2005 by Aurelien Foret <orelien@chez.com>
 *  Copyright (c) 2005 by Christian Hamar <krics@linuxforum.hu>
 *  Copyright (c) 2005, 2006 by Miklos Vajna <vmiklos@frugalware.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <errno.h>
#include <limits.h>

/* libalpm */
#include "trans.h"
#include "alpm_list.h"
#include "package.h"
#include "util.h"
#include "log.h"
#include "handle.h"
#include "remove.h"
#include "sync.h"
#include "alpm.h"

/** \addtogroup alpm_trans Transaction Functions
 * @brief Functions to manipulate libalpm transactions
 * @{
 */

/** Initialize the transaction. */
int SYMEXPORT alpm_trans_init(alpm_handle_t *handle, alpm_transflag_t flags)
{
    alpm_trans_t *trans;

    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);
    ASSERT(handle->trans == NULL, RET_ERR(handle, ALPM_ERR_TRANS_NOT_NULL, -1));

    /* lock db */
    if(!(flags & ALPM_TRANS_FLAG_NOLOCK)) {
        if(_alpm_handle_lock(handle)) {
            RET_ERR(handle, ALPM_ERR_HANDLE_LOCK, -1);
        }
    }

    CALLOC(trans, 1, sizeof(alpm_trans_t), RET_ERR(handle, ALPM_ERR_MEMORY, -1));
    trans->flags = flags;
    trans->state = STATE_INITIALIZED;

    handle->trans = trans;

    return 0;
}

static alpm_list_t *check_arch(alpm_handle_t *handle, alpm_list_t *pkgs)
{
    alpm_list_t *i;
    alpm_list_t *invalid = NULL;

    const char *arch = handle->arch;
    if(!arch) {
        return NULL;
    }
    for(i = pkgs; i; i = i->next) {
        alpm_pkg_t *pkg = i->data;
        const char *pkgarch = alpm_pkg_get_arch(pkg);
        if(pkgarch && strcmp(pkgarch, arch) && strcmp(pkgarch, "any")) {
            char *string;
            const char *pkgname = pkg->name;
            const char *pkgver = pkg->version;
            size_t len = strlen(pkgname) + strlen(pkgver) + strlen(pkgarch) + 3;
            MALLOC(string, len, RET_ERR(handle, ALPM_ERR_MEMORY, invalid));
            sprintf(string, "%s-%s-%s", pkgname, pkgver, pkgarch);
            invalid = alpm_list_add(invalid, string);
        }
    }
    return invalid;
}

/** Prepare a transaction. */
int SYMEXPORT alpm_trans_prepare(alpm_handle_t *handle, alpm_list_t **data)
{
    alpm_trans_t *trans;

    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);
    ASSERT(data != NULL, RET_ERR(handle, ALPM_ERR_WRONG_ARGS, -1));

    trans = handle->trans;

    ASSERT(trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));
    ASSERT(trans->state == STATE_INITIALIZED, RET_ERR(handle, ALPM_ERR_TRANS_NOT_INITIALIZED, -1));

    /* If there's nothing to do, return without complaining */
    if(trans->add == NULL && trans->remove == NULL) {
        return 0;
    }

    alpm_list_t *invalid = check_arch(handle, trans->add);
    if(invalid) {
        if(data) {
            *data = invalid;
        }
        RET_ERR(handle, ALPM_ERR_PKG_INVALID_ARCH, -1);
    }

    if(trans->add == NULL) {
        if(_alpm_remove_prepare(handle, data) == -1) {
            /* pm_errno is set by _alpm_remove_prepare() */
            return -1;
        }
    }   else {
        if(_alpm_sync_prepare(handle, data) == -1) {
            /* pm_errno is set by _alpm_sync_prepare() */
            return -1;
        }
    }

    trans->state = STATE_PREPARED;

    return 0;
}

/** Commit a transaction. */
int SYMEXPORT alpm_trans_commit(alpm_handle_t *handle, alpm_list_t **data)
{
    alpm_trans_t *trans;

    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);

    trans = handle->trans;

    ASSERT(trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));
    ASSERT(trans->state == STATE_PREPARED, RET_ERR(handle, ALPM_ERR_TRANS_NOT_PREPARED, -1));

    ASSERT(!(trans->flags & ALPM_TRANS_FLAG_NOLOCK), RET_ERR(handle, ALPM_ERR_TRANS_NOT_LOCKED, -1));

    /* If there's nothing to do, return without complaining */
    if(trans->add == NULL && trans->remove == NULL) {
        return 0;
    }

    trans->state = STATE_COMMITING;

    if(trans->add == NULL) {
        if(_alpm_remove_packages(handle, 1) == -1) {
            /* pm_errno is set by _alpm_remove_commit() */
            return -1;
        }
    } else {
        if(_alpm_sync_commit(handle, data) == -1) {
            /* pm_errno is set by _alpm_sync_commit() */
            return -1;
        }
    }

    trans->state = STATE_COMMITED;

    return 0;
}

/** Interrupt a transaction. */
int SYMEXPORT alpm_trans_interrupt(alpm_handle_t *handle)
{
    alpm_trans_t *trans;

    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);

    trans = handle->trans;
    ASSERT(trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));
    ASSERT(trans->state == STATE_COMMITING || trans->state == STATE_INTERRUPTED,
            RET_ERR(handle, ALPM_ERR_TRANS_TYPE, -1));

    trans->state = STATE_INTERRUPTED;

    return 0;
}

/** Release a transaction. */
int SYMEXPORT alpm_trans_release(alpm_handle_t *handle)
{
    alpm_trans_t *trans;

    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);

    trans = handle->trans;
    ASSERT(trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));
    ASSERT(trans->state != STATE_IDLE, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));

    int nolock_flag = trans->flags & ALPM_TRANS_FLAG_NOLOCK;

    _alpm_trans_free(trans);
    handle->trans = NULL;

    /* unlock db */
    if(!nolock_flag) {
        if(_alpm_handle_unlock(handle)) {
            _alpm_log(handle, ALPM_LOG_WARNING, _("could not remove lock file %s\n"),
                    handle->lockfile);
            alpm_logaction(handle, "warning: could not remove lock file %s\n",
                    handle->lockfile);
        }
    }

    return 0;
}

/** @} */

void _alpm_trans_free(alpm_trans_t *trans)
{
    if(trans == NULL) {
        return;
    }

    alpm_list_free_inner(trans->unresolvable,
            (alpm_list_fn_free)_alpm_pkg_free_trans);
    alpm_list_free(trans->unresolvable);
    alpm_list_free_inner(trans->add, (alpm_list_fn_free)_alpm_pkg_free_trans);
    alpm_list_free(trans->add);
    alpm_list_free_inner(trans->remove, (alpm_list_fn_free)_alpm_pkg_free);
    alpm_list_free(trans->remove);

    FREELIST(trans->skip_remove);

    FREE(trans);
}

/* A cheap grep for text files, returns 1 if a substring
 * was found in the text file fn, 0 if it wasn't
 */
static int grep(const char *fn, const char *needle)
{
    FILE *fp;

    if((fp = fopen(fn, "r")) == NULL) {
        return 0;
    }
    while(!feof(fp)) {
        char line[1024];
        if(fgets(line, sizeof(line), fp) == NULL) {
            continue;
        }
        /* TODO: this will not work if the search string
         * ends up being split across line reads */
        if(strstr(line, needle)) {
            fclose(fp);
            return 1;
        }
    }
    fclose(fp);
    return 0;
}

int _alpm_runscriptlet(alpm_handle_t *handle, const char *filepath,
        const char *script, const char *ver, const char *oldver, int is_archive)
{
    char cmdline[PATH_MAX];
    char *argv[] = { "sh", "-c", cmdline, NULL };
    char *tmpdir, *scriptfn = NULL, *scriptpath;
    int retval = 0;
    size_t len;

    if(_alpm_access(handle, NULL, filepath, R_OK) != 0) {
        _alpm_log(handle, ALPM_LOG_DEBUG, "scriptlet '%s' not found\n", filepath);
        return 0;
    }

    if(!is_archive && !grep(filepath, script)) {
        /* script not found in scriptlet file; we can only short-circuit this early
         * if it is an actual scriptlet file and not an archive.  */
        return 0;
    }

    /* create a directory in $root/tmp/ for copying/extracting the scriptlet */
    len = strlen(handle->root) + strlen("tmp/alpm_XXXXXX") + 1;
    MALLOC(tmpdir, len, RET_ERR(handle, ALPM_ERR_MEMORY, -1));
    snprintf(tmpdir, len, "%stmp/", handle->root);
    if(access(tmpdir, F_OK) != 0) {
        _alpm_makepath_mode(tmpdir, 01777);
    }
    snprintf(tmpdir, len, "%stmp/alpm_XXXXXX", handle->root);
    if(mkdtemp(tmpdir) == NULL) {
        _alpm_log(handle, ALPM_LOG_ERROR, _("could not create temp directory\n"));
        free(tmpdir);
        return 1;
    }

    /* either extract or copy the scriptlet */
    len += strlen("/.INSTALL");
    MALLOC(scriptfn, len, RET_ERR(handle, ALPM_ERR_MEMORY, -1));
    snprintf(scriptfn, len, "%s/.INSTALL", tmpdir);
    if(is_archive) {
        if(_alpm_unpack_single(handle, filepath, tmpdir, ".INSTALL")) {
            retval = 1;
        }
    } else {
        if(_alpm_copyfile(filepath, scriptfn)) {
            _alpm_log(handle, ALPM_LOG_ERROR, _("could not copy tempfile to %s (%s)\n"), scriptfn, strerror(errno));
            retval = 1;
        }
    }
    if(retval == 1) {
        goto cleanup;
    }

    if(is_archive && !grep(scriptfn, script)) {
        /* script not found in extracted scriptlet file */
        goto cleanup;
    }

    /* chop off the root so we can find the tmpdir in the chroot */
    scriptpath = scriptfn + strlen(handle->root) - 1;

    if(oldver) {
        snprintf(cmdline, PATH_MAX, ". %s; %s %s %s",
                scriptpath, script, ver, oldver);
    } else {
        snprintf(cmdline, PATH_MAX, ". %s; %s %s",
                scriptpath, script, ver);
    }

    _alpm_log(handle, ALPM_LOG_DEBUG, "executing \"%s\"\n", cmdline);

    retval = _alpm_run_chroot(handle, "/bin/sh", argv);

cleanup:
    if(scriptfn && unlink(scriptfn)) {
        _alpm_log(handle, ALPM_LOG_WARNING,
                _("could not remove %s\n"), scriptfn);
    }
    if(rmdir(tmpdir)) {
        _alpm_log(handle, ALPM_LOG_WARNING,
                _("could not remove tmpdir %s\n"), tmpdir);
    }

    free(scriptfn);
    free(tmpdir);
    return retval;
}

alpm_transflag_t SYMEXPORT alpm_trans_get_flags(alpm_handle_t *handle)
{
    /* Sanity checks */
    CHECK_HANDLE(handle, return -1);
    ASSERT(handle->trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, -1));

    return handle->trans->flags;
}

alpm_list_t SYMEXPORT *alpm_trans_get_add(alpm_handle_t *handle)
{
    /* Sanity checks */
    CHECK_HANDLE(handle, return NULL);
    ASSERT(handle->trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, NULL));

    return handle->trans->add;
}

alpm_list_t SYMEXPORT *alpm_trans_get_remove(alpm_handle_t *handle)
{
    /* Sanity checks */
    CHECK_HANDLE(handle, return NULL);
    ASSERT(handle->trans != NULL, RET_ERR(handle, ALPM_ERR_TRANS_NULL, NULL));

    return handle->trans->remove;
}
/* vim: set ts=2 sw=2 noet: */