10 files changed, 266 insertions, 185 deletions

diff --git a/lib/libalpm/alpm.c b/lib/libalpm/alpm.c
index 9b9719d1..b0bbbe8c 100644
--- a/lib/libalpm/alpm.c
+++ b/lib/libalpm/alpm.c
@@ -70,7 +70,7 @@ pmhandle_t SYMEXPORT *alpm_initialize(const char *root, const char *dbpath,
 	snprintf(myhandle->lockfile, lockfilelen, "%s%s", myhandle->dbpath, lf);
 
 	if(_alpm_db_register_local(myhandle) == NULL) {
-		myerr = PM_ERR_DB_CREATE;
+		myerr = myhandle->pm_errno;
 		goto cleanup;
 	}
 
diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
index 715e502a..579b45f2 100644
--- a/lib/libalpm/alpm.h
+++ b/lib/libalpm/alpm.h
@@ -357,9 +357,12 @@ alpm_list_t *alpm_option_get_syncdbs(pmhandle_t *handle);
 /** Register a sync database of packages.
  * @param handle the context handle
  * @param treename the name of the sync repository
+ * @param check_sig what level of signature checking to perform on the
+ * database; note that this must be a '.sig' file type verification
  * @return a pmdb_t* on success (the value), NULL on error
  */
-pmdb_t *alpm_db_register_sync(pmhandle_t *handle, const char *treename);
+pmdb_t *alpm_db_register_sync(pmhandle_t *handle, const char *treename,
+		pgp_verify_t check_sig);
 
 /** Unregister a package database.
  * @param db pointer to the package database to unregister
@@ -999,6 +1002,7 @@ enum _pmerrno_t {
 	PM_ERR_DB_NULL,
 	PM_ERR_DB_NOT_NULL,
 	PM_ERR_DB_NOT_FOUND,
+	PM_ERR_DB_INVALID,
 	PM_ERR_DB_VERSION,
 	PM_ERR_DB_WRITE,
 	PM_ERR_DB_REMOVE,
diff --git a/lib/libalpm/be_local.c b/lib/libalpm/be_local.c
index 4b2a3017..96f04c51 100644
--- a/lib/libalpm/be_local.c
+++ b/lib/libalpm/be_local.c
@@ -314,6 +314,62 @@ static int is_dir(const char *path, struct dirent *entry)
 	return 0;
 }
 
+static int local_db_validate(pmdb_t *db)
+{
+	struct dirent *ent = NULL;
+	const char *dbpath;
+	DIR *dbdir;
+	int ret = -1;
+
+	if(db->status & DB_STATUS_VALID) {
+		return 0;
+	}
+
+	dbpath = _alpm_db_path(db);
+	if(dbpath == NULL) {
+		RET_ERR(db->handle, PM_ERR_DB_OPEN, -1);
+	}
+	dbdir = opendir(dbpath);
+	if(dbdir == NULL) {
+		if(errno == ENOENT) {
+			/* database dir doesn't exist yet */
+			db->status |= DB_STATUS_VALID;
+			return 0;
+		} else {
+			RET_ERR(db->handle, PM_ERR_DB_OPEN, -1);
+		}
+	}
+
+	while((ent = readdir(dbdir)) != NULL) {
+		const char *name = ent->d_name;
+		char path[PATH_MAX];
+
+		if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0) {
+			continue;
+		}
+		if(!is_dir(dbpath, ent)) {
+			continue;
+		}
+
+		snprintf(path, PATH_MAX, "%s%s/depends", dbpath, name);
+		if(access(path, F_OK) == 0) {
+			/* we found a depends file- bail */
+			db->handle->pm_errno = PM_ERR_DB_VERSION;
+			goto done;
+		}
+	}
+	/* we found no depends file after full scan */
+	db->status |= DB_STATUS_VALID;
+	ret = 0;
+
+done:
+	if(dbdir) {
+		closedir(dbdir);
+	}
+
+	return ret;
+}
+
 static int local_db_populate(pmdb_t *db)
 {
 	size_t est_count;
@@ -328,6 +384,7 @@ static int local_db_populate(pmdb_t *db)
 		/* pm_errno set in _alpm_db_path() */
 		return -1;
 	}
+
 	dbdir = opendir(dbpath);
 	if(dbdir == NULL) {
 		if(errno == ENOENT) {
@@ -867,62 +924,9 @@ int _alpm_local_db_remove(pmdb_t *db, pmpkg_t *info)
 	return ret;
 }
 
-static int local_db_version(pmdb_t *db)
-{
-	struct dirent *ent = NULL;
-	const char *dbpath;
-	DIR *dbdir;
-	int version;
-
-	dbpath = _alpm_db_path(db);
-	if(dbpath == NULL) {
-		RET_ERR(db->handle, PM_ERR_DB_OPEN, -1);
-	}
-	dbdir = opendir(dbpath);
-	if(dbdir == NULL) {
-		if(errno == ENOENT) {
-			/* database dir doesn't exist yet */
-			version = 2;
-			goto done;
-		} else {
-			RET_ERR(db->handle, PM_ERR_DB_OPEN, -1);
-		}
-	}
-
-	while((ent = readdir(dbdir)) != NULL) {
-		const char *name = ent->d_name;
-		char path[PATH_MAX];
-
-		if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0) {
-			continue;
-		}
-		if(!is_dir(dbpath, ent)) {
-			continue;
-		}
-
-		snprintf(path, PATH_MAX, "%s%s/depends", dbpath, name);
-		if(access(path, F_OK) == 0) {
-			/* we found a depends file- bail */
-			version = 1;
-			goto done;
-		}
-	}
-	/* we found no depends file after full scan */
-	version = 2;
-
-done:
-	if(dbdir) {
-		closedir(dbdir);
-	}
-
-	_alpm_log(db->handle, PM_LOG_DEBUG, "local database version %d\n", version);
-	return version;
-}
-
 struct db_operations local_db_ops = {
 	.populate         = local_db_populate,
 	.unregister       = _alpm_db_unregister,
-	.version          = local_db_version,
 };
 
 pmdb_t *_alpm_db_register_local(pmhandle_t *handle)
@@ -933,11 +937,18 @@ pmdb_t *_alpm_db_register_local(pmhandle_t *handle)
 
 	db = _alpm_db_new("local", 1);
 	if(db == NULL) {
+		handle->pm_errno = PM_ERR_DB_CREATE;
 		return NULL;
 	}
 	db->ops = &local_db_ops;
 	db->handle = handle;
 
+	if(local_db_validate(db)) {
+		/* pm_errno set in local_db_validate() */
+		_alpm_db_free(db);
+		return NULL;
+	}
+
 	handle->db_local = db;
 	return db;
 }
diff --git a/lib/libalpm/be_sync.c b/lib/libalpm/be_sync.c
index e5fc6a70..f51ab97a 100644
--- a/lib/libalpm/be_sync.c
+++ b/lib/libalpm/be_sync.c
@@ -20,7 +20,9 @@
 
 #include "config.h"
 
+#include <errno.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
 /* libarchive */
 #include <archive.h>
@@ -65,32 +67,68 @@ static char *get_sync_dir(pmhandle_t *handle)
 	return syncpath;
 }
 
+static int sync_db_validate(pmdb_t *db)
+{
+	pgp_verify_t check_sig;
+
+	if(db->status & DB_STATUS_VALID) {
+		return 0;
+	}
+
+	/* this takes into account the default verification level if UNKNOWN
+	 * was assigned to this db */
+	check_sig = _alpm_db_get_sigverify_level(db);
+
+	if(check_sig != PM_PGP_VERIFY_NEVER) {
+		int ret;
+		const char *dbpath = _alpm_db_path(db);
+		if(!dbpath) {
+			/* pm_errno set in _alpm_db_path() */
+			return -1;
+		}
+
+		/* we can skip any validation if the database doesn't exist */
+		if(access(dbpath, R_OK) != 0 && errno == ENOENT) {
+			goto valid;
+			return 0;
+		}
+
+		_alpm_log(db->handle, PM_LOG_DEBUG, "checking signature for %s\n",
+				db->treename);
+		ret = _alpm_gpgme_checksig(db->handle, dbpath, NULL);
+		if((check_sig == PM_PGP_VERIFY_ALWAYS && ret != 0) ||
+				(check_sig == PM_PGP_VERIFY_OPTIONAL && ret == 1)) {
+			RET_ERR(db->handle, PM_ERR_SIG_INVALID, -1);
+		}
+	}
+
+valid:
+	db->status |= DB_STATUS_VALID;
+	return 0;
+}
+
 /** Update a package database
  *
  * An update of the package database \a db will be attempted. Unless
  * \a force is true, the update will only be performed if the remote
  * database was modified since the last update.
  *
- * A transaction is necessary for this operation, in order to obtain a
- * database lock. During this transaction the front-end will be informed
- * of the download progress of the database via the download callback.
+ * This operation requires a database lock, and will return an applicable error
+ * if the lock could not be obtained.
  *
  * Example:
  * @code
  * alpm_list_t *syncs = alpm_option_get_syncdbs();
- * if(alpm_trans_init(0, NULL, NULL, NULL) == 0) {
- *     for(i = syncs; i; i = alpm_list_next(i)) {
- *         pmdb_t *db = alpm_list_getdata(i);
- *         result = alpm_db_update(0, db);
- *         alpm_trans_release();
+ * for(i = syncs; i; i = alpm_list_next(i)) {
+ *     pmdb_t *db = alpm_list_getdata(i);
+ *     result = alpm_db_update(0, db);
  *
- *         if(result < 0) {
- *	           printf("Unable to update database: %s\n", alpm_strerrorlast());
- *         } else if(result == 1) {
- *             printf("Database already up to date\n");
- *         } else {
- *             printf("Database updated\n");
- *         }
+ *     if(result < 0) {
+ *	       printf("Unable to update database: %s\n", alpm_strerrorlast());
+ *     } else if(result == 1) {
+ *         printf("Database already up to date\n");
+ *     } else {
+ *         printf("Database updated\n");
  *     }
  * }
  * @endcode
@@ -120,15 +158,21 @@ int SYMEXPORT alpm_db_update(int force, pmdb_t *db)
 	ASSERT(db != handle->db_local, RET_ERR(handle, PM_ERR_WRONG_ARGS, -1));
 	ASSERT(db->servers != NULL, RET_ERR(handle, PM_ERR_SERVER_NONE, -1));
 
-	/* make sure we have a sane umask */
-	oldmask = umask(0022);
-
 	syncpath = get_sync_dir(handle);
 	if(!syncpath) {
 		return -1;
 	}
+
+	/* make sure we have a sane umask */
+	oldmask = umask(0022);
+
 	check_sig = _alpm_db_get_sigverify_level(db);
 
+	/* attempt to grab a lock */
+	if(_alpm_handle_lock(handle)) {
+		RET_ERR(handle, PM_ERR_HANDLE_LOCK, -1);
+	}
+
 	for(i = db->servers; i; i = i->next) {
 		const char *server = i->data;
 		char *fileurl;
@@ -144,6 +188,15 @@ int SYMEXPORT alpm_db_update(int force, pmdb_t *db)
 
 		if(ret == 0 && (check_sig == PM_PGP_VERIFY_ALWAYS ||
 					check_sig == PM_PGP_VERIFY_OPTIONAL)) {
+			/* an existing sig file is no good at this point */
+			char *sigpath = _alpm_db_sig_path(db);
+			if(!sigpath) {
+				ret = -1;
+				break;
+			}
+			unlink(sigpath);
+			free(sigpath);
+
 			int errors_ok = (check_sig == PM_PGP_VERIFY_OPTIONAL);
 			/* if we downloaded a DB, we want the .sig from the same server */
 			snprintf(fileurl, len, "%s/%s.db.sig", server, db->treename);
@@ -173,8 +226,18 @@ int SYMEXPORT alpm_db_update(int force, pmdb_t *db)
 	/* Cache needs to be rebuilt */
 	_alpm_db_free_pkgcache(db);
 
+	db->status &= ~DB_STATUS_VALID;
+	if(sync_db_validate(db)) {
+		/* pm_errno should be set */
+		ret = -1;
+	}
+
 cleanup:
 
+	if(_alpm_handle_unlock(handle)) {
+		_alpm_log(handle, PM_LOG_WARNING, _("could not remove lock file %s\n"),
+				alpm_option_get_lockfile(handle));
+	}
 	free(syncpath);
 	umask(oldmask);
 	return ret;
@@ -512,18 +575,13 @@ error:
 	return -1;
 }
 
-static int sync_db_version(pmdb_t UNUSED *db)
-{
-	return 2;
-}
-
 struct db_operations sync_db_ops = {
 	.populate         = sync_db_populate,
 	.unregister       = _alpm_db_unregister,
-	.version          = sync_db_version,
 };
 
-pmdb_t *_alpm_db_register_sync(pmhandle_t *handle, const char *treename)
+pmdb_t *_alpm_db_register_sync(pmhandle_t *handle, const char *treename,
+		pgp_verify_t level)
 {
 	pmdb_t *db;
 
@@ -535,6 +593,12 @@ pmdb_t *_alpm_db_register_sync(pmhandle_t *handle, const char *treename)
 	}
 	db->ops = &sync_db_ops;
 	db->handle = handle;
+	db->pgp_verify = level;
+
+	if(sync_db_validate(db)) {
+		_alpm_db_free(db);
+		return NULL;
+	}
 
 	handle->dbs_sync = alpm_list_add(handle->dbs_sync, db);
 	return db;
diff --git a/lib/libalpm/db.c b/lib/libalpm/db.c
index c3a7abd2..b20421a3 100644
--- a/lib/libalpm/db.c
+++ b/lib/libalpm/db.c
@@ -45,7 +45,8 @@
  */
 
 /** Register a sync database of packages. */
-pmdb_t SYMEXPORT *alpm_db_register_sync(pmhandle_t *handle, const char *treename)
+pmdb_t SYMEXPORT *alpm_db_register_sync(pmhandle_t *handle, const char *treename,
+		pgp_verify_t check_sig)
 {
 	/* Sanity checks */
 	CHECK_HANDLE(handle, return NULL);
@@ -54,7 +55,7 @@ pmdb_t SYMEXPORT *alpm_db_register_sync(pmhandle_t *handle, const char *treename
 	/* Do not register a database if a transaction is on-going */
 	ASSERT(handle->trans == NULL, RET_ERR(handle, PM_ERR_TRANS_NOT_NULL, NULL));
 
-	return _alpm_db_register_sync(handle, treename);
+	return _alpm_db_register_sync(handle, treename, check_sig);
 }
 
 /* Helper function for alpm_db_unregister{_all} */
@@ -369,14 +370,6 @@ const char *_alpm_db_path(pmdb_t *db)
 	return db->_path;
 }
 
-int _alpm_db_version(pmdb_t *db)
-{
-	if(!db) {
-		return -1;
-	}
-	return db->ops->version(db);
-}
-
 char *_alpm_db_sig_path(pmdb_t *db)
 {
 	char *sigpath;
@@ -475,11 +468,8 @@ alpm_list_t *_alpm_db_search(pmdb_t *db, const alpm_list_t *needles)
 /* Returns a new package cache from db.
  * It frees the cache if it already exists.
  */
-int _alpm_db_load_pkgcache(pmdb_t *db)
+static int load_pkgcache(pmdb_t *db)
 {
-	if(db == NULL) {
-		return -1;
-	}
 	_alpm_db_free_pkgcache(db);
 
 	_alpm_log(db->handle, PM_LOG_DEBUG, "loading package cache for repository '%s'\n",
@@ -490,23 +480,23 @@ int _alpm_db_load_pkgcache(pmdb_t *db)
 		return -1;
 	}
 
-	db->pkgcache_loaded = 1;
+	db->status |= DB_STATUS_PKGCACHE;
 	return 0;
 }
 
 void _alpm_db_free_pkgcache(pmdb_t *db)
 {
-	if(db == NULL || !db->pkgcache_loaded) {
+	if(db == NULL || !(db->status & DB_STATUS_PKGCACHE)) {
 		return;
 	}
 
-	_alpm_log(db->handle, PM_LOG_DEBUG, "freeing package cache for repository '%s'\n",
-	                        db->treename);
+	_alpm_log(db->handle, PM_LOG_DEBUG,
+			"freeing package cache for repository '%s'\n", db->treename);
 
 	alpm_list_free_inner(_alpm_db_get_pkgcache(db),
 				(alpm_list_fn_free)_alpm_pkg_free);
 	_alpm_pkghash_free(db->pkgcache);
-	db->pkgcache_loaded = 0;
+	db->status &= ~DB_STATUS_PKGCACHE;
 
 	_alpm_db_free_grpcache(db);
 }
@@ -517,13 +507,12 @@ pmpkghash_t *_alpm_db_get_pkgcache_hash(pmdb_t *db)
 		return NULL;
 	}
 
-	if(!db->pkgcache_loaded) {
-		_alpm_db_load_pkgcache(db);
+	if(!(db->status & DB_STATUS_VALID)) {
+		RET_ERR(db->handle, PM_ERR_DB_INVALID, NULL);
 	}
 
-	/* hmmm, still NULL ?*/
-	if(!db->pkgcache) {
-		_alpm_log(db->handle, PM_LOG_DEBUG, "warning: pkgcache is NULL for db '%s'\n", db->treename);
+	if(!(db->status & DB_STATUS_PKGCACHE)) {
+		load_pkgcache(db);
 	}
 
 	return db->pkgcache;
@@ -545,7 +534,7 @@ int _alpm_db_add_pkgincache(pmdb_t *db, pmpkg_t *pkg)
 {
 	pmpkg_t *newpkg;
 
-	if(db == NULL || !db->pkgcache_loaded || pkg == NULL) {
+	if(db == NULL || pkg == NULL || !(db->status & DB_STATUS_PKGCACHE)) {
 		return -1;
 	}
 
@@ -567,7 +556,7 @@ int _alpm_db_remove_pkgfromcache(pmdb_t *db, pmpkg_t *pkg)
 {
 	pmpkg_t *data = NULL;
 
-	if(db == NULL || !db->pkgcache_loaded || pkg == NULL) {
+	if(db == NULL || pkg == NULL || !(db->status & DB_STATUS_PKGCACHE)) {
 		return -1;
 	}
 
@@ -597,8 +586,6 @@ pmpkg_t *_alpm_db_get_pkgfromcache(pmdb_t *db, const char *target)
 
 	pmpkghash_t *pkgcache = _alpm_db_get_pkgcache_hash(db);
 	if(!pkgcache) {
-		_alpm_log(db->handle, PM_LOG_DEBUG, "warning: failed to get '%s' from NULL pkgcache\n",
-				target);
 		return NULL;
 	}
 
@@ -607,7 +594,7 @@ pmpkg_t *_alpm_db_get_pkgfromcache(pmdb_t *db, const char *target)
 
 /* Returns a new group cache from db.
  */
-int _alpm_db_load_grpcache(pmdb_t *db)
+static int load_grpcache(pmdb_t *db)
 {
 	alpm_list_t *lp;
 
@@ -653,7 +640,7 @@ int _alpm_db_load_grpcache(pmdb_t *db)
 		}
 	}
 
-	db->grpcache_loaded = 1;
+	db->status |= DB_STATUS_GRPCACHE;
 	return 0;
 }
 
@@ -661,19 +648,19 @@ void _alpm_db_free_grpcache(pmdb_t *db)
 {
 	alpm_list_t *lg;
 
-	if(db == NULL || !db->grpcache_loaded) {
+	if(db == NULL || !(db->status & DB_STATUS_GRPCACHE)) {
 		return;
 	}
 
-	_alpm_log(db->handle, PM_LOG_DEBUG, "freeing group cache for repository '%s'\n",
-	                        db->treename);
+	_alpm_log(db->handle, PM_LOG_DEBUG,
+			"freeing group cache for repository '%s'\n", db->treename);
 
 	for(lg = db->grpcache; lg; lg = lg->next) {
 		_alpm_grp_free(lg->data);
 		lg->data = NULL;
 	}
 	FREELIST(db->grpcache);
-	db->grpcache_loaded = 0;
+	db->status &= ~DB_STATUS_GRPCACHE;
 }
 
 alpm_list_t *_alpm_db_get_grpcache(pmdb_t *db)
@@ -682,8 +669,12 @@ alpm_list_t *_alpm_db_get_grpcache(pmdb_t *db)
 		return NULL;
 	}
 
-	if(!db->grpcache_loaded) {
-		_alpm_db_load_grpcache(db);
+	if(!(db->status & DB_STATUS_VALID)) {
+		RET_ERR(db->handle, PM_ERR_DB_INVALID, NULL);
+	}
+
+	if(!(db->status & DB_STATUS_GRPCACHE)) {
+		load_grpcache(db);
 	}
 
 	return db->grpcache;
diff --git a/lib/libalpm/db.h b/lib/libalpm/db.h
index e3faeeb4..03187342 100644
--- a/lib/libalpm/db.h
+++ b/lib/libalpm/db.h
@@ -43,10 +43,16 @@ typedef enum _pmdbinfrq_t {
 	INFRQ_ALL = 0x1F
 } pmdbinfrq_t;
 
+/** Database status. Bitflags. */
+enum _pmdbstatus_t {
+	DB_STATUS_VALID = (1 << 0),
+	DB_STATUS_PKGCACHE = (1 << 1),
+	DB_STATUS_GRPCACHE = (1 << 2)
+};
+
 struct db_operations {
 	int (*populate) (pmdb_t *);
 	void (*unregister) (pmdb_t *);
-	int (*version) (pmdb_t *);
 };
 
 /* Database */
@@ -55,10 +61,10 @@ struct __pmdb_t {
 	char *treename;
 	/* do not access directly, use _alpm_db_path(db) for lazy access */
 	char *_path;
-	int pkgcache_loaded;
-	int grpcache_loaded;
 	/* also indicates whether we are RO or RW */
 	int is_local;
+	/* flags determining validity, loaded caches, etc. */
+	enum _pmdbstatus_t status;
 	pmpkghash_t *pkgcache;
 	alpm_list_t *grpcache;
 	alpm_list_t *servers;
@@ -73,11 +79,11 @@ pmdb_t *_alpm_db_new(const char *treename, int is_local);
 void _alpm_db_free(pmdb_t *db);
 const char *_alpm_db_path(pmdb_t *db);
 char *_alpm_db_sig_path(pmdb_t *db);
-int _alpm_db_version(pmdb_t *db);
 int _alpm_db_cmp(const void *d1, const void *d2);
 alpm_list_t *_alpm_db_search(pmdb_t *db, const alpm_list_t *needles);
 pmdb_t *_alpm_db_register_local(pmhandle_t *handle);
-pmdb_t *_alpm_db_register_sync(pmhandle_t *handle, const char *treename);
+pmdb_t *_alpm_db_register_sync(pmhandle_t *handle, const char *treename,
+		pgp_verify_t level);
 void _alpm_db_unregister(pmdb_t *db);
 
 /* be_*.c, backend specific calls */
@@ -88,7 +94,6 @@ int _alpm_local_db_remove(pmdb_t *db, pmpkg_t *info);
 
 /* cache bullshit */
 /* packages */
-int _alpm_db_load_pkgcache(pmdb_t *db);
 void _alpm_db_free_pkgcache(pmdb_t *db);
 int _alpm_db_add_pkgincache(pmdb_t *db, pmpkg_t *pkg);
 int _alpm_db_remove_pkgfromcache(pmdb_t *db, pmpkg_t *pkg);
@@ -97,7 +102,6 @@ alpm_list_t *_alpm_db_get_pkgcache(pmdb_t *db);
 int _alpm_db_ensure_pkgcache(pmdb_t *db, pmdbinfrq_t infolevel);
 pmpkg_t *_alpm_db_get_pkgfromcache(pmdb_t *db, const char *target);
 /* groups */
-int _alpm_db_load_grpcache(pmdb_t *db);
 void _alpm_db_free_grpcache(pmdb_t *db);
 alpm_list_t *_alpm_db_get_grpcache(pmdb_t *db);
 pmgrp_t *_alpm_db_get_grpfromcache(pmdb_t *db, const char *target);
diff --git a/lib/libalpm/error.c b/lib/libalpm/error.c
index d893f866..1e4e705b 100644
--- a/lib/libalpm/error.c
+++ b/lib/libalpm/error.c
@@ -70,6 +70,8 @@ const char SYMEXPORT *alpm_strerror(enum _pmerrno_t err)
 			return _("database already registered");
 		case PM_ERR_DB_NOT_FOUND:
 			return _("could not find database");
+		case PM_ERR_DB_INVALID:
+			return _("invalid or corrupted database");
 		case PM_ERR_DB_VERSION:
 			return _("database is incorrect version");
 		case PM_ERR_DB_WRITE:
diff --git a/lib/libalpm/handle.c b/lib/libalpm/handle.c
index b535e0f3..acd35409 100644
--- a/lib/libalpm/handle.c
+++ b/lib/libalpm/handle.c
@@ -22,12 +22,14 @@
 
 #include "config.h"
 
+#include <errno.h>
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
 #include <sys/types.h>
 #include <syslog.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 
 /* libalpm */
 #include "handle.h"
@@ -86,6 +88,58 @@ void _alpm_handle_free(pmhandle_t *handle)
 	FREE(handle);
 }
 
+/** Lock the database */
+int _alpm_handle_lock(pmhandle_t *handle)
+{
+	int fd;
+	char *dir, *ptr;
+
+	ASSERT(handle->lockfile != NULL, return -1);
+	ASSERT(handle->lckstream == NULL, return 0);
+
+	/* create the dir of the lockfile first */
+	dir = strdup(handle->lockfile);
+	ptr = strrchr(dir, '/');
+	if(ptr) {
+		*ptr = '\0';
+	}
+	if(_alpm_makepath(dir)) {
+		FREE(dir);
+		return -1;
+	}
+	FREE(dir);
+
+	do {
+		fd = open(handle->lockfile, O_WRONLY | O_CREAT | O_EXCL, 0000);
+	} while(fd == -1 && errno == EINTR);
+	if(fd > 0) {
+		FILE *f = fdopen(fd, "w");
+		fprintf(f, "%ld\n", (long)getpid());
+		fflush(f);
+		fsync(fd);
+		handle->lckstream = f;
+		return 0;
+	}
+	return -1;
+}
+
+/** Remove a lock file */
+int _alpm_handle_unlock(pmhandle_t *handle)
+{
+	ASSERT(handle->lockfile != NULL, return -1);
+	ASSERT(handle->lckstream != NULL, return 0);
+
+	if(handle->lckstream != NULL) {
+		fclose(handle->lckstream);
+		handle->lckstream = NULL;
+	}
+	if(unlink(handle->lockfile) && errno != ENOENT) {
+		return -1;
+	}
+	return 0;
+}
+
+
 alpm_cb_log SYMEXPORT alpm_option_get_logcb(pmhandle_t *handle)
 {
 	CHECK_HANDLE(handle, return NULL);
diff --git a/lib/libalpm/handle.h b/lib/libalpm/handle.h
index 2de6efdd..4ffd00c4 100644
--- a/lib/libalpm/handle.h
+++ b/lib/libalpm/handle.h
@@ -78,6 +78,9 @@ struct __pmhandle_t {
 pmhandle_t *_alpm_handle_new(void);
 void _alpm_handle_free(pmhandle_t *handle);
 
+int _alpm_handle_lock(pmhandle_t *handle);
+int _alpm_handle_unlock(pmhandle_t *handle);
+
 enum _pmerrno_t _alpm_set_directory_option(const char *value,
 		char **storage, int must_exist);
 
diff --git a/lib/libalpm/trans.c b/lib/libalpm/trans.c
index f0744937..507ea027 100644
--- a/lib/libalpm/trans.c
+++ b/lib/libalpm/trans.c
@@ -30,7 +30,6 @@
 #include <sys/types.h>
 #include <errno.h>
 #include <limits.h>
-#include <fcntl.h>
 
 /* libalpm */
 #include "trans.h"
@@ -48,69 +47,28 @@
  * @{
  */
 
-/* Create a lock file */
-static int make_lock(pmhandle_t *handle)
-{
-	int fd;
-	char *dir, *ptr;
-
-	ASSERT(handle->lockfile != NULL, return -1);
-
-	/* create the dir of the lockfile first */
-	dir = strdup(handle->lockfile);
-	ptr = strrchr(dir, '/');
-	if(ptr) {
-		*ptr = '\0';
-	}
-	if(_alpm_makepath(dir)) {
-		FREE(dir);
-		return -1;
-	}
-	FREE(dir);
-
-	do {
-		fd = open(handle->lockfile, O_WRONLY | O_CREAT | O_EXCL, 0000);
-	} while(fd == -1 && errno == EINTR);
-	if(fd > 0) {
-		FILE *f = fdopen(fd, "w");
-		fprintf(f, "%ld\n", (long)getpid());
-		fflush(f);
-		fsync(fd);
-		handle->lckstream = f;
-		return 0;
-	}
-	return -1;
-}
-
-/* Remove a lock file */
-static int remove_lock(pmhandle_t *handle)
-{
-	if(handle->lckstream != NULL) {
-		fclose(handle->lckstream);
-		handle->lckstream = NULL;
-	}
-	if(unlink(handle->lockfile) == -1 && errno != ENOENT) {
-		return -1;
-	}
-	return 0;
-}
-
 /** Initialize the transaction. */
 int SYMEXPORT alpm_trans_init(pmhandle_t *handle, pmtransflag_t flags,
 		alpm_trans_cb_event event, alpm_trans_cb_conv conv,
 		alpm_trans_cb_progress progress)
 {
 	pmtrans_t *trans;
-	const int required_db_version = 2;
-	int db_version;
+	alpm_list_t *i;
 
 	/* Sanity checks */
 	CHECK_HANDLE(handle, return -1);
 	ASSERT(handle->trans == NULL, RET_ERR(handle, PM_ERR_TRANS_NOT_NULL, -1));
 
+	for(i = handle->dbs_sync; i; i = i->next) {
+		const pmdb_t *db = i->data;
+		if(!(db->status & DB_STATUS_VALID)) {
+			RET_ERR(handle, PM_ERR_DB_INVALID, -1);
+		}
+	}
+
 	/* lock db */
 	if(!(flags & PM_TRANS_FLAG_NOLOCK)) {
-		if(make_lock(handle)) {
+		if(_alpm_handle_lock(handle)) {
 			RET_ERR(handle, PM_ERR_HANDLE_LOCK, -1);
 		}
 	}
@@ -122,16 +80,6 @@ int SYMEXPORT alpm_trans_init(pmhandle_t *handle, pmtransflag_t flags,
 	trans->cb_progress = progress;
 	trans->state = STATE_INITIALIZED;
 
-	/* check database version */
-	db_version = _alpm_db_version(handle->db_local);
-	if(db_version < required_db_version) {
-		_alpm_log(handle, PM_LOG_ERROR,
-				_("%s database version is too old\n"), handle->db_local->treename);
-		remove_lock(handle);
-		_alpm_trans_free(trans);
-		RET_ERR(handle, PM_ERR_DB_VERSION, -1);
-	}
-
 	handle->trans = trans;
 
 	return 0;
@@ -282,7 +230,7 @@ int SYMEXPORT alpm_trans_release(pmhandle_t *handle)
 
 	/* unlock db */
 	if(!nolock_flag) {
-		if(remove_lock(handle)) {
+		if(_alpm_handle_unlock(handle)) {
 			_alpm_log(handle, PM_LOG_WARNING, _("could not remove lock file %s\n"),
 					alpm_option_get_lockfile(handle));
 			alpm_logaction(handle, "warning: could not remove lock file %s\n",