Add function to match file to mount point

For a given file, determine which mount point it is on or will be
installed to.  Take into account that we might be using an alternative
installation root.

Add additional helper function added to sort mount point list for easier
matching.

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

1 files changed, 28 insertions, 0 deletions

diff --git a/lib/libalpm/diskspace.c b/lib/libalpm/diskspace.c
index a5beb84f..9d153fb4 100644
--- a/lib/libalpm/diskspace.c
+++ b/lib/libalpm/diskspace.c
@@ -38,6 +38,12 @@
 #include "alpm_list.h"
 #include "util.h"
 #include "log.h"
+#include "handle.h"
+
+static int mount_point_cmp(const alpm_mountpoint_t *mp1, const alpm_mountpoint_t *mp2)
+{
+	return(strcmp(mp1->mount_dir, mp2->mount_dir));
+}
 
 static alpm_list_t *mount_point_list()
 {
@@ -121,9 +127,31 @@ static alpm_list_t *mount_point_list()
 	}
 #endif
 
+	mount_points = alpm_list_msort(mount_points, alpm_list_count(mount_points),
+	                                   (alpm_list_fn_cmp)mount_point_cmp);
 	return(mount_points);
 }
 
+static alpm_list_t *match_mount_point(const alpm_list_t *mount_points, const char *file)
+{
+	char real_path[PATH_MAX];
+	snprintf(real_path, PATH_MAX, "%s%s", handle->root, file);
+
+	alpm_list_t *mp = alpm_list_last(mount_points);
+	do {
+		alpm_mountpoint_t *data = mp->data;
+
+		if(strncmp(data->mount_dir, real_path, strlen(data->mount_dir)) == 0) {
+			return mp;
+		}
+
+		mp = mp->prev;
+	} while (mp != alpm_list_last(mount_points));
+
+	/* should not get here... */
+	return NULL;
+}
+
 int _alpm_check_diskspace(pmtrans_t *trans, pmdb_t *db)
 {
 	alpm_list_t *mount_points;