db.c

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/*
 *  db.c
 *
 *  Copyright (c) 2002-2007 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) 2006 by David Kimpe <dnaku@frugalware.org>
 *  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 "config.h"

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <stdint.h> /* uintmax_t */
#include <sys/stat.h>
#include <dirent.h>
#include <regex.h>
#include <time.h>

/* libalpm */
#include "db.h"
#include "alpm_list.h"
#include "log.h"
#include "util.h"
#include "error.h"
#include "server.h"
#include "handle.h"
#include "cache.h"
#include "alpm.h"

/** \addtogroup alpm_databases Database Functions
 * @brief Functions to query and manipulate the database of libalpm
 * @{
 */

/** Register a sync database of packages.
 * @param treename the name of the sync repository
 * @return a pmdb_t* on success (the value), NULL on error
 */
pmdb_t SYMEXPORT *alpm_db_register_sync(const char *treename)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, NULL));
    ASSERT(treename != NULL && strlen(treename) != 0, RET_ERR(PM_ERR_WRONG_ARGS, NULL));
    /* Do not register a database if a transaction is on-going */
    ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, NULL));

    return(_alpm_db_register_sync(treename));
}

/** Register the local package database.
 * @return a pmdb_t* representing the local database, or NULL on error
 */
pmdb_t SYMEXPORT *alpm_db_register_local(void)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, NULL));
    /* Do not register a database if a transaction is on-going */
    ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, NULL));

    return(_alpm_db_register_local());
}

/* Helper function for alpm_db_unregister{_all} */
static void _alpm_db_unregister(pmdb_t *db)
{
    if(db == NULL) {
        return;
    }

    _alpm_log(PM_LOG_DEBUG, "closing database '%s'\n", db->treename);
    _alpm_db_close(db);

    _alpm_log(PM_LOG_DEBUG, "unregistering database '%s'\n", db->treename);
    _alpm_db_free(db);
}

/** Unregister all package databases
 * @return 0 on success, -1 on error (pm_errno is set accordingly)
 */
int SYMEXPORT alpm_db_unregister_all(void)
{
    alpm_list_t *i;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, -1));
    /* Do not unregister a database if a transaction is on-going */
    ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));

    /* close local database */
    _alpm_db_unregister(handle->db_local);
    handle->db_local = NULL;

    /* and also sync ones */
    for(i = handle->dbs_sync; i; i = i->next) {
        pmdb_t *db = i->data;
        _alpm_db_unregister(db);
        i->data = NULL;
    }
    FREELIST(handle->dbs_sync);
    return(0);
}

/** Unregister a package database
 * @param db pointer to the package database to unregister
 * @return 0 on success, -1 on error (pm_errno is set accordingly)
 */
int SYMEXPORT alpm_db_unregister(pmdb_t *db)
{
    int found = 0;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, -1));
    ASSERT(db != NULL, RET_ERR(PM_ERR_WRONG_ARGS, -1));
    /* Do not unregister a database if a transaction is on-going */
    ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));

    if(db == handle->db_local) {
        handle->db_local = NULL;
        found = 1;
    } else {
        /* Warning : this function shouldn't be used to unregister all sync
         * databases by walking through the list returned by
         * alpm_option_get_syncdbs, because the db is removed from that list here.
         */
        void *data;
        handle->dbs_sync = alpm_list_remove(handle->dbs_sync,
                db, _alpm_db_cmp, &data);
        if(data) {
            found = 1;
        }
    }

    if(!found) {
        RET_ERR(PM_ERR_DB_NOT_FOUND, -1);
    }

    _alpm_db_unregister(db);
    return(0);
}

/** Set the serverlist of a database.
 * @param db database pointer
 * @param url url of the server
 * @return 0 on success, -1 on error (pm_errno is set accordingly)
 */
int SYMEXPORT alpm_db_setserver(pmdb_t *db, const char *url)
{
    alpm_list_t *i;
    int found = 0;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(db != NULL, RET_ERR(PM_ERR_DB_NULL, -1));

    for(i = handle->dbs_sync; i && !found; i = i->next) {
        pmdb_t *sdb = i->data;
        if(strcmp(db->treename, sdb->treename) == 0) {
            found = 1;
        }
    }
    if(!found) {
        RET_ERR(PM_ERR_DB_NOT_FOUND, -1);
    }

    if(url && strlen(url)) {
        pmserver_t *server;
        if((server = _alpm_server_new(url)) == NULL) {
            /* pm_errno is set by _alpm_server_new */
            return(-1);
        }
        db->servers = alpm_list_add(db->servers, server);
        _alpm_log(PM_LOG_DEBUG, "adding new server to database '%s': protocol '%s', server '%s', path '%s'\n",
                            db->treename, server->s_url->scheme, server->s_url->host, server->s_url->doc);
    } else {
        FREELIST(db->servers);
        _alpm_log(PM_LOG_DEBUG, "serverlist flushed for '%s'\n", db->treename);
    }

    return(0);
}

/** Update a package database
 * @param force if true, then forces the update, otherwise update only in case
 * the database isn't up to date
 * @param db pointer to the package database to update
 * @return 0 on success, > 0 on error (pm_errno is set accordingly), < 0 if up
 * to date
 */
int SYMEXPORT alpm_db_update(int force, pmdb_t *db)
{
    alpm_list_t *lp;
    char path[PATH_MAX];
    alpm_list_t *files = NULL;
    time_t newmtime = 0, lastupdate = 0;
    const char *dbpath;
    int ret;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, -1));
    ASSERT(db != NULL && db != handle->db_local, RET_ERR(PM_ERR_WRONG_ARGS, -1));
    /* Verify we are in a transaction.  This is done _mainly_ because we need a DB
     * lock - if we update without a db lock, we may kludge some other pacman
     * process that _has_ a lock.
     */
    ASSERT(handle->trans != NULL, RET_ERR(PM_ERR_TRANS_NULL, -1));
    ASSERT(handle->trans->state == STATE_INITIALIZED, RET_ERR(PM_ERR_TRANS_NOT_INITIALIZED, -1));
    ASSERT(handle->trans->type == PM_TRANS_TYPE_SYNC, RET_ERR(PM_ERR_TRANS_TYPE, -1));

    if(!alpm_list_find_ptr(handle->dbs_sync, db)) {
        RET_ERR(PM_ERR_DB_NOT_FOUND, -1);
    }

    if(!force) {
        /* get the lastupdate time */
        lastupdate = _alpm_db_getlastupdate(db);
        if(lastupdate == 0) {
            _alpm_log(PM_LOG_DEBUG, "failed to get lastupdate time for %s\n",
                    db->treename);
        }
    }

    /* build a one-element list */
    snprintf(path, PATH_MAX, "%s" DBEXT, db->treename);
    files = alpm_list_add(files, strdup(path));

    dbpath = alpm_option_get_dbpath();

    ret = _alpm_downloadfiles_forreal(db->servers, dbpath, files, lastupdate,
            &newmtime, NULL, 0);
    FREELIST(files);
    if(ret == 1) {
        /* mtimes match, do nothing */
        pm_errno = 0;
        return(1);
    } else if(ret == -1) {
        /* we use downloadLastErrString and downloadLastErrCode here, error returns from
         * libdownload */
        _alpm_log(PM_LOG_DEBUG, "failed to sync db: %s [%d]\n",
                downloadLastErrString, downloadLastErrCode);
        RET_ERR(PM_ERR_DB_SYNC, -1);
    } else {
        if(newmtime != 0) {
            _alpm_log(PM_LOG_DEBUG, "sync: new mtime for %s: %ju\n",
                    db->treename, (uintmax_t)newmtime);
            _alpm_db_setlastupdate(db, newmtime);
        }
        snprintf(path, PATH_MAX, "%s%s" DBEXT, dbpath, db->treename);

        /* remove the old dir */
        _alpm_log(PM_LOG_DEBUG, "flushing database %s\n", db->path);
        for(lp = _alpm_db_get_pkgcache(db); lp; lp = lp->next) {
            pmpkg_t *pkg = lp->data;
            if(pkg && _alpm_db_remove(db, pkg) == -1) {
                _alpm_log(PM_LOG_ERROR, _("could not remove database entry %s%s\n"), db->treename,
                                    alpm_pkg_get_name(pkg));
                RET_ERR(PM_ERR_DB_REMOVE, -1);
            }
        }

        /* Cache needs to be rebuild */
        _alpm_db_free_pkgcache(db);

        /* uncompress the sync database */
        if(_alpm_db_install(db, path) == -1) {
            return -1;
        }
    }

    return(0);
}

/** Get the name of a package database
 * @param db pointer to the package database
 * @return the name of the package database, NULL on error
 */
const char SYMEXPORT *alpm_db_get_name(const pmdb_t *db)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));

    return db->treename;
}

/** Get a download URL for the package database
 * @param db pointer to the package database
 * @return a fully-specified download URL, NULL on error
 */
const char SYMEXPORT *alpm_db_get_url(const pmdb_t *db)
{
    char path[PATH_MAX];
    pmserver_t *s;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));

    s = (pmserver_t*)db->servers->data;

    snprintf(path, PATH_MAX, "%s://%s%s", s->s_url->scheme, s->s_url->host, s->s_url->doc);
    return strdup(path);
}


/** Get a package entry from a package database
 * @param db pointer to the package database to get the package from
 * @param name of the package
 * @return the package entry on success, NULL on error
 */
pmpkg_t SYMEXPORT *alpm_db_get_pkg(pmdb_t *db, const char *name)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));
    ASSERT(name != NULL && strlen(name) != 0, return(NULL));

    return(_alpm_db_get_pkgfromcache(db, name));
}

/** Get the package cache of a package database
 * @param db pointer to the package database to get the package from
 * @return the list of packages on success, NULL on error
 */
alpm_list_t SYMEXPORT *alpm_db_getpkgcache(pmdb_t *db)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));

    return(_alpm_db_get_pkgcache(db));
}

/** Get the list of packages that a package provides
 * @param db pointer to the package database to get the package from
 * @param name name of the package
 * @return the list of packages on success, NULL on error
 */
alpm_list_t SYMEXPORT *alpm_db_whatprovides(pmdb_t *db, const char *name)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));
    ASSERT(name != NULL && strlen(name) != 0, return(NULL));

    return(_alpm_db_whatprovides(db, name));
}

/** Get a group entry from a package database
 * @param db pointer to the package database to get the group from
 * @param name of the group
 * @return the groups entry on success, NULL on error
 */
pmgrp_t SYMEXPORT *alpm_db_readgrp(pmdb_t *db, const char *name)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));
    ASSERT(name != NULL && strlen(name) != 0, return(NULL));

    return(_alpm_db_get_grpfromcache(db, name));
}

/** Get the group cache of a package database
 * @param db pointer to the package database to get the group from
 * @return the list of groups on success, NULL on error
 */
alpm_list_t SYMEXPORT *alpm_db_getgrpcache(pmdb_t *db)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));

    return(_alpm_db_get_grpcache(db));
}

/** Searches a database
 * @param db pointer to the package database to search in
 * @param needles the list of strings to search for
 * @return the list of packages on success, NULL on error
 */
alpm_list_t SYMEXPORT *alpm_db_search(pmdb_t *db, const alpm_list_t* needles)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(handle != NULL, return(NULL));
    ASSERT(db != NULL, return(NULL));

    return(_alpm_db_search(db, needles));
}

/** @} */

pmdb_t *_alpm_db_new(const char *dbpath, const char *treename)
{
    pmdb_t *db;
    const size_t pathsize = strlen(dbpath) + strlen(treename) + 2;

    ALPM_LOG_FUNC;

    CALLOC(db, 1, sizeof(pmdb_t), RET_ERR(PM_ERR_MEMORY, NULL));
    CALLOC(db->path, 1, pathsize, RET_ERR(PM_ERR_MEMORY, NULL));

    sprintf(db->path, "%s%s/", dbpath, treename);

    strncpy(db->treename, treename, PATH_MAX);

    return(db);
}

void _alpm_db_free(pmdb_t *db)
{
    alpm_list_t *tmp;

    ALPM_LOG_FUNC;

    /* cleanup pkgcache */
    _alpm_db_free_pkgcache(db);
    /* cleanup server list */
    for(tmp = db->servers; tmp; tmp = alpm_list_next(tmp)) {
        _alpm_server_free(tmp->data);
    }
    alpm_list_free(db->servers);
    FREE(db->path);
    FREE(db);

    return;
}

int _alpm_db_cmp(const void *db1, const void *db2)
{
    ALPM_LOG_FUNC;
    return(strcmp(((pmdb_t *)db1)->treename, ((pmdb_t *)db2)->treename));
}

alpm_list_t *_alpm_db_search(pmdb_t *db, const alpm_list_t *needles)
{
    const alpm_list_t *i, *j, *k;
    alpm_list_t *ret = NULL;

    ALPM_LOG_FUNC;

    for(i = needles; i; i = i->next) {
        char *targ;
        regex_t reg;

        if(i->data == NULL) {
            continue;
        }
        targ = i->data;
        _alpm_log(PM_LOG_DEBUG, "searching for target '%s'\n", targ);

        if(regcomp(&reg, targ, REG_EXTENDED | REG_NOSUB | REG_ICASE | REG_NEWLINE) != 0) {
            RET_ERR(PM_ERR_INVALID_REGEX, NULL);
        }

        for(j = _alpm_db_get_pkgcache(db); j; j = j->next) {
            pmpkg_t *pkg = j->data;
            const char *matched = NULL;
            const char *name = alpm_pkg_get_name(pkg);
            const char *desc = alpm_pkg_get_desc(pkg);

            /* check name as regex AND as plain text */
            if(name && (regexec(&reg, name, 0, 0, 0) == 0 || strstr(name, targ))) {
                matched = name;
            }
            /* check desc */
            else if (desc && regexec(&reg, desc, 0, 0, 0) == 0) {
                matched = desc;
            }
            /* check provides */
            /* TODO: should we be doing this, and should we print something
             * differently when we do match it since it isn't currently printed? */
            else {
                for(k = alpm_pkg_get_provides(pkg); k; k = k->next) {
                    if (regexec(&reg, k->data, 0, 0, 0) == 0) {
                        matched = k->data;
                        break;
                    }
                }
            }

            if(matched != NULL) {
                _alpm_log(PM_LOG_DEBUG, "    search target '%s' matched '%s'\n",
                          targ, matched);
                ret = alpm_list_add(ret, pkg);
            }
        }

        regfree(&reg);
    }

    return(ret);
}

pmdb_t *_alpm_db_register_local(void)
{
    struct stat buf;
    pmdb_t *db;
    const char *dbpath;
    char path[PATH_MAX];

    ALPM_LOG_FUNC;

    if(handle->db_local != NULL) {
        _alpm_log(PM_LOG_WARNING, _("attempt to re-register the 'local' DB\n"));
        RET_ERR(PM_ERR_DB_NOT_NULL, NULL);
    }

    _alpm_log(PM_LOG_DEBUG, "registering local database\n");

    /* make sure the database directory exists */
    dbpath = alpm_option_get_dbpath();
    if(!dbpath) {
        _alpm_log(PM_LOG_ERROR, _("database path is undefined\n"));
            RET_ERR(PM_ERR_DB_OPEN, NULL);
    }
    snprintf(path, PATH_MAX, "%slocal", dbpath);
    /* TODO this is rediculous, we try to do this even if we can't */
    if(stat(path, &buf) != 0 || !S_ISDIR(buf.st_mode)) {
        _alpm_log(PM_LOG_DEBUG, "database dir '%s' does not exist, creating it\n",
                path);
        if(_alpm_makepath(path) != 0) {
            RET_ERR(PM_ERR_SYSTEM, NULL);
        }
    }

    db = _alpm_db_new(dbpath, "local");
    if(db == NULL) {
        RET_ERR(PM_ERR_DB_CREATE, NULL);
    }

    _alpm_log(PM_LOG_DEBUG, "opening database '%s'\n", db->treename);
    if(_alpm_db_open(db) == -1) {
        _alpm_db_free(db);
        RET_ERR(PM_ERR_DB_OPEN, NULL);
    }

    handle->db_local = db;
    return(db);
}

pmdb_t *_alpm_db_register_sync(const char *treename)
{
    struct stat buf;
    pmdb_t *db;
    const char *dbpath;
    char path[PATH_MAX];
    alpm_list_t *i;

    ALPM_LOG_FUNC;

    for(i = handle->dbs_sync; i; i = i->next) {
        pmdb_t *sdb = i->data;
        if(strcmp(treename, sdb->treename) == 0) {
            _alpm_log(PM_LOG_DEBUG, "attempt to re-register the '%s' database, using existing\n", sdb->treename);
            return sdb;
        }
    }

    _alpm_log(PM_LOG_DEBUG, "registering sync database '%s'\n", treename);

    /* make sure the database directory exists */
    dbpath = alpm_option_get_dbpath();
    if(!dbpath) {
        _alpm_log(PM_LOG_ERROR, _("database path is undefined\n"));
            RET_ERR(PM_ERR_DB_OPEN, NULL);
    }
    /* all sync DBs now reside in the sync/ subdir of the dbpath */
    snprintf(path, PATH_MAX, "%ssync/%s", dbpath, treename);
    /* TODO this is rediculous, we try to do this even if we can't */
    if(stat(path, &buf) != 0 || !S_ISDIR(buf.st_mode)) {
        _alpm_log(PM_LOG_DEBUG, "database dir '%s' does not exist, creating it\n",
                path);
        if(_alpm_makepath(path) != 0) {
            RET_ERR(PM_ERR_SYSTEM, NULL);
        }
    }

    /* Ensure the db gets the real path. */
    path[0] = '\0';
    snprintf(path, PATH_MAX, "%ssync/", dbpath);

    db = _alpm_db_new(path, treename);
    if(db == NULL) {
        RET_ERR(PM_ERR_DB_CREATE, NULL);
    }

    _alpm_log(PM_LOG_DEBUG, "opening database '%s'\n", db->treename);
    if(_alpm_db_open(db) == -1) {
        _alpm_db_free(db);
        RET_ERR(PM_ERR_DB_OPEN, NULL);
    }

    handle->dbs_sync = alpm_list_add(handle->dbs_sync, db);
    return(db);
}

/* helper function for alpm_list_find and _alpm_db_whatprovides
 *
 * @return "provision.name" == needle (as string)
 */
int _alpm_prov_cmp(const void *provision, const void *needle)
{
    char *tmpptr;
    char *provname = strdup(provision);
    int retval = 0;
    tmpptr = strchr(provname, '=');

    if(tmpptr != NULL) { /* provision-version */
        *tmpptr='\0';
    }
    retval = strcmp(provname, needle);
    free(provname);
    return(retval);
}

/* return a alpm_list_t of packages in "db" that provide "package"
 */
alpm_list_t *_alpm_db_whatprovides(pmdb_t *db, const char *package)
{
    alpm_list_t *pkgs = NULL;
    alpm_list_t *lp;

    ALPM_LOG_FUNC;

    if(db == NULL || package == NULL || strlen(package) == 0) {
        return(NULL);
    }

    for(lp = _alpm_db_get_pkgcache(db); lp; lp = lp->next) {
        pmpkg_t *info = lp->data;

        if(alpm_list_find(alpm_pkg_get_provides(info), (const void *)package, _alpm_prov_cmp)) {
            pkgs = alpm_list_add(pkgs, info);
        }
    }

    return(pkgs);
}

/* vim: set ts=2 sw=2 noet: */

---