HashIndex: fix list_by_hash handling of next->is_max()

get_path_str() should not handle hobject_t::get_max().  get_path_str()
now asserts that the passed object is not max and the callers now check
for is_max().  This caused HashIndex.cc to incorrectly scan an entire
collection before returning no objects rather than scanning the top
level and returning no objects.  It did not actually list_by_hash to
return an incorrect answer, however.

Signed-off-by: Samuel Just <sam.just@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/os/HashIndex.cc b/src/os/HashIndex.cc
index 34a7074bce0..8948c506411 100644
--- a/src/os/HashIndex.cc
+++ b/src/os/HashIndex.cc
@@ -371,6 +371,7 @@ string HashIndex::get_hash_str(uint32_t hash) {
 }
 
 string HashIndex::get_path_str(const hobject_t &hoid) {
+  assert(!hoid.is_max());
   return get_hash_str(hoid.hash);
 }
 
@@ -428,7 +429,8 @@ int HashIndex::get_path_contents_by_hash(const vector<string> &path,
     if (lower_bound && candidate < lower_bound->substr(0, candidate.size()))
       continue;
     if (next_object &&
-	candidate < get_path_str(*next_object).substr(0, candidate.size()))
+        (next_object->is_max() ||
+	 candidate < get_path_str(*next_object).substr(0, candidate.size())))
       continue;
     hash_prefixes->insert(cur_prefix + *i);
   }