From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Will Thompson <[email protected]>
Date: Wed, 11 Jul 2018 15:41:09 +0100
Subject: [PATCH] blscfg: sort BLS entries by 'version' field
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This partially reverts ‘Use BLS fragment filename as menu entry id and
for criteria to sort’. Sorting by filename only gives the correct order
if the BLS entries are generated by a version of ostree after this patch
https://github.com/ostreedev/ostree/commit/9f48e212a3bf9ed418fb3216e4f834d581bc520e
to use the version (higher is newer) in the filename. Older ostrees,
including all releases at the time of writing, use the index (lower is
newer) in the filename, so sorting by filename produces the reverse
order.

Sorting by 'version' field matches libostree's own
compare_boot_loader_configs(), so I think it's more correct than relying
on the filename, particularly since we've already gone to the trouble of
parsing all the fields in the file.

Signed-off-by: Will Thompson <[email protected]>
---
 grub-core/commands/blscfg.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/grub-core/commands/blscfg.c b/grub-core/commands/blscfg.c
index b61dddb7f..9c928dda4 100644
--- a/grub-core/commands/blscfg.c
+++ b/grub-core/commands/blscfg.c
@@ -327,10 +327,26 @@ finish:
     return ret;
 }
 
+/* return 1: p0 is newer than p1 */
+/*        0: p0 and p1 are the same version */
+/*       -1: p1 is newer than p0 */
 static int bls_cmp(const void *p0, const void *p1, void *state UNUSED)
 {
   struct bls_entry * e0 = *(struct bls_entry **)p0;
   struct bls_entry * e1 = *(struct bls_entry **)p1;
+  const char *v0, *v1;
+  int r;
+
+  v0 = bls_get_val(e0, "version", NULL);
+  v1 = bls_get_val(e1, "version", NULL);
+
+  if (v0 && !v1)
+    return -1;
+  if (!v0 && v1)
+    return 1;
+
+  if ((r = vercmp(v0, v1)) != 0)
+    return r;
 
   return vercmp(e0->filename, e1->filename);
 }