ErasureCodeJerasure: unit test common to all techniques

A typed unit test is defined and must run regardless of the technique.
When a new technique is derived from ErasureCodeJerasure, it is added
to the JerasureTypes typedef and the test will validate that:

  * it provides reasonable defaults for the technique specific
    parameters
  * it modifies the k, m and w to reasonable defaults depending
    on the imposed constraints ( for instance Liber8tion requires
    that w == 8 but the test sets it to 7 )
  * the encoding of K=2, M=2 produces 4 chunks, the first two
    of which contains the original buffer data showing the
    code is systematic
  * decoding when all 4 chunks are available indeed retrieves
    the original buffer content
  * decoding when the two data chunks are are missing indeed
    retrieves the original buffer content

https://github.com/dachary/ceph/tree/wip-5879 refs #5879

Signed-off-by: Loic Dachary <loic@dachary.org>

2 files changed, 110 insertions, 0 deletions

diff --git a/src/test/Makefile.am b/src/test/Makefile.am
index 72246ac748f..7f0dc88b8a0 100644
--- a/src/test/Makefile.am
+++ b/src/test/Makefile.am
@@ -328,6 +328,15 @@ unittest_erasure_code_plugin_LDADD += -ldl
 endif
 check_PROGRAMS += unittest_erasure_code_plugin
 
+unittest_erasure_code_jerasure_SOURCES = \
+	test/osd/TestErasureCodeJerasure.cc \
+	$(libec_jerasure_la_SOURCES)
+unittest_erasure_code_jerasure_CXXFLAGS = $(UNITTEST_CXXFLAGS)
+unittest_erasure_code_jerasure_LDADD = $(LIBOSD) $(LIBCOMMON) $(UNITTEST_LDADD) $(CEPH_GLOBAL)
+if LINUX
+unittest_erasure_code_jerasure_LDADD += -ldl
+endif
+check_PROGRAMS += unittest_erasure_code_jerasure
 
 unittest_erasure_code_example_SOURCES = test/osd/TestErasureCodeExample.cc 
 noinst_HEADERS += test/osd/ErasureCodeExample.h
diff --git a/src/test/osd/TestErasureCodeJerasure.cc b/src/test/osd/TestErasureCodeJerasure.cc
new file mode 100644
index 00000000000..96fc834b10e
--- /dev/null
+++ b/src/test/osd/TestErasureCodeJerasure.cc
@@ -0,0 +1,101 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- 
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2013 Cloudwatt <libre.licensing@cloudwatt.com>
+ *
+ * Author: Loic Dachary <loic@dachary.org>
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ * 
+ */
+
+#include "global/global_init.h"
+#include "osd/ErasureCodePluginJerasure/ErasureCodeJerasure.h"
+#include "common/ceph_argparse.h"
+#include "global/global_context.h"
+#include "gtest/gtest.h"
+
+template <typename T>
+class ErasureCodeTest : public ::testing::Test {
+ public:
+};
+
+typedef ::testing::Types<
+> JerasureTypes;
+TYPED_TEST_CASE(ErasureCodeTest, JerasureTypes);
+
+TYPED_TEST(ErasureCodeTest, encode_decode) {
+  TypeParam jerasure;
+  map<std::string,std::string> parameters;
+  parameters["erasure-code-k"] = "2";
+  parameters["erasure-code-m"] = "2";
+  parameters["erasure-code-w"] = "7";
+  parameters["erasure-code-packetsize"] = "8";
+  jerasure.init(parameters);
+
+  bufferlist in;
+  for (int i = 0; i < 5; i++)
+    in.append("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
+  int want_to_encode[] = { 0, 1, 2, 3 };
+  map<int, bufferlist> encoded;
+  EXPECT_EQ(0, jerasure.encode(set<int>(want_to_encode, want_to_encode+4),
+                              in,
+                              &encoded));
+  EXPECT_EQ(4u, encoded.size());
+  unsigned length =  encoded[0].length();
+  EXPECT_EQ(0, strncmp(encoded[0].c_str(), in.c_str(), length));
+  EXPECT_EQ(0, strncmp(encoded[1].c_str(), in.c_str() + length, in.length() - length));
+
+
+  // all chunks are available
+  {
+    int want_to_decode[] = { 0, 1 };
+    map<int, bufferlist> decoded;
+    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(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, in.length() - length));
+  }
+
+  // two chunks are missing 
+  {
+    map<int, bufferlist> degraded = encoded;
+    degraded.erase(0);
+    degraded.erase(1);
+    EXPECT_EQ(2u, degraded.size());
+    int want_to_decode[] = { 0, 1 };
+    map<int, bufferlist> decoded;
+    EXPECT_EQ(0, jerasure.decode(set<int>(want_to_decode, want_to_decode+2),
+                                degraded,
+                                &decoded));
+    // always decode all, regardless of want_to_decode
+    EXPECT_EQ(4u, 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, in.length() - length));
+  }
+}
+
+int main(int argc, char **argv) {
+  vector<const char*> args;
+  argv_to_vec(argc, (const char **)argv, args);
+
+  global_init(NULL, args, CEPH_ENTITY_TYPE_CLIENT, CODE_ENVIRONMENT_UTILITY, 0);
+  common_init_finish(g_ceph_context);
+
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}
+
+// Local Variables:
+// compile-command: "cd ../.. ; make -j4 && make unittest_erasure_code_jerasure && valgrind --tool=memcheck ./unittest_erasure_code_jerasure --gtest_filter=*.* --log-to-stderr=true --debug-osd=20"
+// End: