From: Samuel Just <sam.just@inktank.com>
Date: Tue, 4 Feb 2014 01:09:28 +0000 (-0800)
Subject: ErasureCodeJerasure: fill in decoded if all shards are included
X-Git-Tag: v0.78~163^2~56
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=3650da69b552c206800dcc7e8e0ff45b7f56c69e;p=ceph.git

ErasureCodeJerasure: fill in decoded if all shards are included

This causes it to match minimum_to_decode.

Signed-off-by: Samuel Just <sam.just@inktank.com>
---

diff --git a/src/erasure-code/jerasure/ErasureCodeJerasure.cc b/src/erasure-code/jerasure/ErasureCodeJerasure.cc
index 9200da25ea7c..26f978dad58b 100644
--- a/src/erasure-code/jerasure/ErasureCodeJerasure.cc
+++ b/src/erasure-code/jerasure/ErasureCodeJerasure.cc
@@ -136,6 +136,22 @@ int ErasureCodeJerasure::decode(const set<int> &want_to_read,
                                 const map<int, bufferlist> &chunks,
                                 map<int, bufferlist> *decoded)
 {
+  vector<int> have;
+  have.reserve(chunks.size());
+  for (map<int, bufferlist>::const_iterator i = chunks.begin();
+       i != chunks.end();
+       ++i) {
+    have.push_back(i->first);
+  }
+  if (includes(
+	have.begin(), have.end(), want_to_read.begin(), want_to_read.end())) {
+    for (set<int>::iterator i = want_to_read.begin();
+	 i != want_to_read.end();
+	 ++i) {
+      (*decoded)[*i] = chunks.find(*i)->second;
+    }
+    return 0;
+  }
   unsigned blocksize = (*chunks.begin()).second.length();
   int erasures[k + m + 1];
   int erasures_count = 0;
diff --git a/src/test/erasure-code/TestErasureCodeJerasure.cc b/src/test/erasure-code/TestErasureCodeJerasure.cc
index a3d603bea540..87f59667baaa 100644
--- a/src/test/erasure-code/TestErasureCodeJerasure.cc
+++ b/src/test/erasure-code/TestErasureCodeJerasure.cc
@@ -82,8 +82,7 @@ TYPED_TEST(ErasureCodeTest, encode_decode)
     EXPECT_EQ(0, jerasure.decode(set<int>(want_to_decode, want_to_decode+2),
                                 encoded,
                                 &decoded));
-    // always decode all, regardless of want_to_decode
-    EXPECT_EQ(4u, decoded.size()); 
+    EXPECT_EQ(2u, decoded.size()); 
     EXPECT_EQ(length, decoded[0].length());
     EXPECT_EQ(0, strncmp(decoded[0].c_str(), in.c_str(), length));
     EXPECT_EQ(0, strncmp(decoded[1].c_str(), in.c_str() + length,