[PATCH] Make unlocking error messages uniform

[Ashok Gautham Jadatharan]

Upon failing to unlock the database, pacman -Su provides a useful tip
related to unlocking it by deleting /var/lib/pacman/db.lck if it already
exists.
This fixes pacman -Syu to provide the same tip upon failing to lock.

Signed-off-by: Ashok Gautham Jadatharan <ScriptDevil at zoho.com>
---
 src/pacman/util.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/pacman/util.c b/src/pacman/util.c
index 0f50ae0b..d3422739 100644
--- a/src/pacman/util.c
+++ b/src/pacman/util.c
@@ -152,12 +152,25 @@ int sync_syncdbs(int level, alpm_list_t *syncs)
 {
 	int ret;
 	int force = (level < 2 ? 0 : 1);
+	alpm_errno_t err;
 
 	multibar_move_completed_up(false);
 	ret = alpm_db_update(config->handle, syncs, force);
+
 	if(ret < 0) {
+		err = alpm_errno(config->handle);
 		pm_printf(ALPM_LOG_ERROR, _("failed to synchronize all databases (%s)\n"),
-			alpm_strerror(alpm_errno(config->handle)));
+			alpm_strerror(err));
+
+		if(err == ALPM_ERR_HANDLE_LOCK) {
+			const char *lockfile = alpm_option_get_lockfile(config->handle);
+			pm_printf(ALPM_LOG_ERROR, _("could not lock database: %s\n"),
+						strerror(errno));
+			if(access(lockfile, F_OK) == 0) {
+				fprintf(stderr, _("  if you're sure a package manager is not already\n"
+							"  running, you can remove %s\n"), lockfile);
+			}
+		}
 	}
 
 	return (ret >= 0);
-- 
2.34.1