commit dc5a137125d6ac641c566f10e68bf6e1fe31bcb5
author Paolo Bonzini <pbonzini@redhat.com> Tue May 08 16:51:50 2012 +0200
committer Kevin Wolf <kwolf@redhat.com> Thu May 10 10:32:12 2012 +0200
tree 27ae82c1b297705351bbfdd8852b416e4804e4e3
parent 6405875cdd10e531ad3dedaad86ae1ccc4b14f20

qemu-img: make "info" backing file output correct and easier to use

qemu-img info should use the same logic as qemu when printing the
backing file path, or debugging becomes quite tricky.  We can also
simplify the output in case the backing file has an absolute path
or a protocol.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

diff --git a/block.c b/block.c
index 2986998..af2ab4f 100644
--- a/block.c
+++ b/block.c
@@ -270,6 +270,15 @@
     }
 }
 
+void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz)
+{
+    if (bs->backing_file[0] == '\0' || path_has_protocol(bs->backing_file)) {
+        pstrcpy(dest, sz, bs->backing_file);
+    } else {
+        path_combine(dest, sz, bs->filename, bs->backing_file);
+    }
+}
+
 void bdrv_register(BlockDriver *bdrv)
 {
     /* Block drivers without coroutine functions need emulation */
@@ -796,14 +805,8 @@
         BlockDriver *back_drv = NULL;
 
         bs->backing_hd = bdrv_new("");
-
-        if (path_has_protocol(bs->backing_file)) {
-            pstrcpy(backing_filename, sizeof(backing_filename),
-                    bs->backing_file);
-        } else {
-            path_combine(backing_filename, sizeof(backing_filename),
-                         filename, bs->backing_file);
-        }
+        bdrv_get_full_backing_filename(bs, backing_filename,
+                                       sizeof(backing_filename));
 
         if (bs->backing_format[0] != '\0') {
             back_drv = bdrv_find_format(bs->backing_format);