trans.c : reworking of transaction interruptions

My two previous hacks related to this part
(8038190c7c4786e1c49494eea1b40cdddcbd5136 and
b15a5194d1a8485a2769560e49e6ff03e1862533) were caused by the lack of
understanding of a feature introduced a while ago:
Better control over CTRL-C interruptions -- do not leave the DB in an
inconsistent state (54008798efcc9646f622f6b052ecd83281d57cda).

Now I have been looking at this commit, and the added feature is indeed
interesting. The main problem I had with it is that it does a rather
unusual use of alpm_trans_release, which caused a few problems that I tried
to fix in a weird way. I think these problems were caused by the fact that
there weren't any difference between "interrupt transaction" and "release a
transaction which failed" actions from the alpm_trans_release POV.  So I
decided to add a new function instead, alpm_trans_interrupt, which is
called on Ctrl+C, and which only sets trans->state to STATE_INTERRUPTED so
that remove_commit and add_commit can exit cleanly at a safe moment. This
allowed me to revert my two previous hacks as well.

Also ensure we handle SIGINT correctly in all cases- if a transaction is
not ongoing, then we can free the transaction and exit quickly.

Signed-off-by: Chantry Xavier <shiningxc@gmail.com>
Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 2 insertions, 4 deletions

diff --git a/lib/libalpm/db.c b/lib/libalpm/db.c
index 61c74a77..b06a970c 100644
--- a/lib/libalpm/db.c
+++ b/lib/libalpm/db.c
@@ -111,8 +111,7 @@ int SYMEXPORT alpm_db_unregister_all(void)
 	/* 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 || handle->trans->state == STATE_INTERRUPTED,
-			RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));
+	ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));
 
 	/* close local database */
 	_alpm_db_unregister(handle->db_local);
@@ -142,8 +141,7 @@ int SYMEXPORT alpm_db_unregister(pmdb_t *db)
 	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 || handle->trans->state == STATE_INTERRUPTED,
-			RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));
+	ASSERT(handle->trans == NULL, RET_ERR(PM_ERR_TRANS_NOT_NULL, -1));
 
 	if(db == handle->db_local) {
 		handle->db_local = NULL;