Enhance and utilize database status flags

* Move is_local standalone field to status enum
* Create VALID/INVALID flag pair
* Create EXISTS/MISSING flag pair

With these additional fields, we can be more intelligent with database
loading and messages to the user. We now only warn once if a sync
database does not exist and do not continue to try to load it once we
have marked it as missing.

The reason for the flags existing in pairs is so the unknown case can be
represented. There should never be a time when both flags in the same
group are true, but if they are both false, it represents the unknown
case. Care is taken to always manipulate both flags at the same time.

Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/libalpm/be_local.c b/lib/libalpm/be_local.c
index a874504e..5b69f628 100644
--- a/lib/libalpm/be_local.c
+++ b/lib/libalpm/be_local.c
@@ -318,6 +318,9 @@ static int local_db_validate(alpm_db_t *db)
 	if(db->status & DB_STATUS_VALID) {
 		return 0;
 	}
+	if(db->status & DB_STATUS_INVALID) {
+		return -1;
+	}
 
 	dbpath = _alpm_db_path(db);
 	if(dbpath == NULL) {
@@ -328,11 +331,16 @@ static int local_db_validate(alpm_db_t *db)
 		if(errno == ENOENT) {
 			/* database dir doesn't exist yet */
 			db->status |= DB_STATUS_VALID;
+			db->status &= ~DB_STATUS_INVALID;
+			db->status &= ~DB_STATUS_EXISTS;
+			db->status |= DB_STATUS_MISSING;
 			return 0;
 		} else {
 			RET_ERR(db->handle, ALPM_ERR_DB_OPEN, -1);
 		}
 	}
+	db->status |= DB_STATUS_EXISTS;
+	db->status &= ~DB_STATUS_MISSING;
 
 	while((ent = readdir(dbdir)) != NULL) {
 		const char *name = ent->d_name;
@@ -348,12 +356,15 @@ static int local_db_validate(alpm_db_t *db)
 		snprintf(path, PATH_MAX, "%s%s/depends", dbpath, name);
 		if(access(path, F_OK) == 0) {
 			/* we found a depends file- bail */
+			db->status &= ~DB_STATUS_VALID;
+			db->status |= DB_STATUS_INVALID;
 			db->handle->pm_errno = ALPM_ERR_DB_VERSION;
 			goto done;
 		}
 	}
 	/* we found no depends file after full scan */
 	db->status |= DB_STATUS_VALID;
+	db->status &= ~DB_STATUS_INVALID;
 	ret = 0;
 
 done:
@@ -373,6 +384,11 @@ static int local_db_populate(alpm_db_t *db)
 	const char *dbpath;
 	DIR *dbdir;
 
+	if(db->status & DB_STATUS_INVALID) {
+		RET_ERR(db->handle, ALPM_ERR_DB_INVALID, -1);
+	}
+	/* note: DB_STATUS_MISSING is not fatal for local database */
+
 	dbpath = _alpm_db_path(db);
 	if(dbpath == NULL) {
 		/* pm_errno set in _alpm_db_path() */
@@ -383,6 +399,8 @@ static int local_db_populate(alpm_db_t *db)
 	if(dbdir == NULL) {
 		if(errno == ENOENT) {
 			/* no database existing yet is not an error */
+			db->status &= ~DB_STATUS_EXISTS;
+			db->status |= DB_STATUS_MISSING;
 			return 0;
 		}
 		RET_ERR(db->handle, ALPM_ERR_DB_OPEN, -1);
@@ -390,6 +408,8 @@ static int local_db_populate(alpm_db_t *db)
 	if(fstat(dirfd(dbdir), &buf) != 0) {
 		RET_ERR(db->handle, ALPM_ERR_DB_OPEN, -1);
 	}
+	db->status |= DB_STATUS_EXISTS;
+	db->status &= ~DB_STATUS_MISSING;
 	if(buf.st_nlink >= 2) {
 		est_count = buf.st_nlink;
 	} else {