rgw: merge manifests correctly when there's prefix override

Fixes: #11622
Backport: hammer, firefly

Prefix override happens in a manifest when a rados object does not
conform to the generic prefix set on the manifest. When merging
manifests (specifically being used in multipart objects upload), we need
to check if the rule that we try to merge has a prefix that is the same
as the previous rule. Beforehand we checked if both had the same
override_prefix setting, but that might not apply as both manifests
might have different prefixes.

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
(cherry picked from commit 389ae6739ddc6239a4dd7c5f7f9bfc9b645b8577)

diff --git a/src/rgw/rgw_rados.cc b/src/rgw/rgw_rados.cc
index 604d4cb8ba715761fb26d86e4452fe0d38982929..2ee23bd13851d0f1817caa2ecb2dd18052fe9ee7 100644 (file)
--- a/src/rgw/rgw_rados.cc
+++ b/src/rgw/rgw_rados.cc
@@ -773,15 +773,24 @@ int RGWObjManifest::append(RGWObjManifest& m)
       next_rule.part_size = m.obj_size - next_rule.start_ofs;
     }
 
-    if (override_prefix != rule.override_prefix) {
-      append_rules(m, miter, &override_prefix);
-      break;
+    string rule_prefix = prefix;
+    if (!rule.override_prefix.empty()) {
+      rule_prefix = rule.override_prefix;
+    }
+
+    string next_rule_prefix = m.prefix;
+    if (!next_rule.override_prefix.empty()) {
+      next_rule_prefix = next_rule.override_prefix;
     }
 
     if (rule.part_size != next_rule.part_size ||
         rule.stripe_max_size != next_rule.stripe_max_size ||
-        rule.override_prefix != next_rule.override_prefix) {
-      append_rules(m, miter, NULL);
+        rule_prefix != next_rule_prefix) {
+      if (next_rule_prefix != prefix) {
+        append_rules(m, miter, &next_rule_prefix);
+      } else {
+        append_rules(m, miter, NULL);
+      }
       break;
     }