Give sensible feedback when a repo has no configured servers

This fixes FS#14899. When running an -Sp operation without servers
configured for a repository, we would segfault, so add an assert to the
backend method returning the first server preventing a null pointer
dereference.

In addition, add a new error code to libalpm that indicates we have no
servers configured for a repository. This makes -Sy and -S <package>
operations fail gracefully and helpfully when a repo is set up with no
servers, as the default mirrorlist in Arch is provided this way.

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

1 files changed, 9 insertions, 1 deletions

diff --git a/src/pacman/sync.c b/src/pacman/sync.c
index 68fb81a9..2e57b011 100644
--- a/src/pacman/sync.c
+++ b/src/pacman/sync.c
@@ -675,7 +675,15 @@ static int sync_trans(alpm_list_t *targets)
 		for(i = packages; i; i = alpm_list_next(i)) {
 			pmpkg_t *pkg = alpm_list_getdata(i);
 			pmdb_t *db = alpm_pkg_get_db(pkg);
-			printf("%s/%s\n", alpm_db_get_url(db), alpm_pkg_get_filename(pkg));
+			const char *dburl = alpm_db_get_url(db);
+			if(dburl) {
+				printf("%s/%s\n", dburl, alpm_pkg_get_filename(pkg));
+			} else {
+				/* can't use WARNING here, we don't show warnings in -Sp... */
+				pm_fprintf(stderr, PM_LOG_ERROR, _("no database for package: %s\n"),
+						alpm_pkg_get_name(pkg));
+			}
+
 		}
 		/* we are done */
 		goto cleanup;