More followup on issue 188, correction to frontier_blkno calculation (was wrong when last block is full)

1 files changed, 51 insertions, 13 deletions

diff --git a/xdelta3/testing/regtest.cc b/xdelta3/testing/regtest.cc
index 69f8f80..aec3b2a 100644
--- a/xdelta3/testing/regtest.cc
+++ b/xdelta3/testing/regtest.cc
@@ -12,12 +12,14 @@ public:
     Options()
       : encode_srcwin_maxsz(1<<20),
         block_size(Constants::BLOCK_SIZE),
+        window_size(Constants::WINDOW_SIZE),
         size_known(false),
         iopt_size(XD3_DEFAULT_IOPT_SIZE),
         smatch_cfg(XD3_SMATCH_DEFAULT) { }
 
     xoff_t encode_srcwin_maxsz;
     size_t block_size;
+    xoff_t window_size;
     bool size_known;
     usize_t iopt_size;
     xd3_smatch_cfg smatch_cfg;
@@ -56,7 +58,7 @@ public:
     xd3_init_config(&encode_config, XD3_ADLER32);
     xd3_init_config(&decode_config, XD3_ADLER32);
 
-    encode_config.winsize = Constants::WINDOW_SIZE;
+    encode_config.winsize = options.window_size;
     encode_config.iopt_size = options.iopt_size;
     encode_config.smatch_cfg = options.smatch_cfg;
 
@@ -152,10 +154,10 @@ public:
         Block *block = (encoding ? &encode_source_block : &decode_source_block);
         if (encoding) {
           IF_DEBUG1(XPR(NTR "[srcblock] %"Q"u last srcpos %"Q"u "
-                       "encodepos %"Q"u\n",
-                       encode_source.getblkno,
-                       encode_stream.match_last_srcpos,
-                       encode_stream.input_position + encode_stream.total_in));
+                        "encodepos %"Q"u\n",
+                        encode_source.getblkno,
+                        encode_stream.match_last_srcpos,
+                        encode_stream.input_position + encode_stream.total_in));
         }
 
         source_iterator.SetBlock(src->getblkno);
@@ -228,10 +230,10 @@ public:
                         ExtFile *coded_data,
                         const Options &options) {
     vector<const char*> ecmd;
-    char wbuf[16];
-    snprintf(wbuf, sizeof(wbuf), "-B%"Q"u", options.encode_srcwin_maxsz);
+    char bbuf[16];
+    snprintf(bbuf, sizeof(bbuf), "-B%"Q"u", options.encode_srcwin_maxsz);
     ecmd.push_back("xdelta3");
-    ecmd.push_back(wbuf);
+    ecmd.push_back(bbuf);
     ecmd.push_back("-s");
     ecmd.push_back(source_file.Name());
     ecmd.push_back(target_file.Name());
@@ -244,7 +246,7 @@ public:
     vector<const char*> dcmd;
     ExtFile recon_file;
     dcmd.push_back("xdelta3");
-    ecmd.push_back(wbuf);
+    ecmd.push_back(bbuf);
     dcmd.push_back("-d");
     dcmd.push_back("-s");
     dcmd.push_back(source_file.Name());
@@ -837,7 +839,6 @@ void TestCopyWindow() {
     options.encode_srcwin_maxsz = size;
     options.iopt_size = 128;
     options.smatch_cfg = XD3_SMATCH_SLOW;
-    options.size_known = false;
 
     Block block1;
     InMemoryEncodeDecode(spec0, spec1, &block1, options);
@@ -952,7 +953,7 @@ void TestHalfBlockCopy() {
       Options options;
       options.encode_srcwin_maxsz = Constants::BLOCK_SIZE * b;
 
-      Block block0;
+      // Block block0;
       Block block1;
       InMemoryEncodeDecode(spec0, spec1, &block0, options);
       InMemoryEncodeDecode(spec1, spec0, &block1, options);
@@ -978,7 +979,6 @@ void TestHalfBlockCopy() {
           // When there are fewer than 3 source blocks.
           CHECK_EQ(nocopy_adds, delta1.AddedBytes());
         }
-      // XPR(NT "0=%zu 1=%zu\n", delta0.AddedBytes(), delta1.AddedBytes());
     }
 
   Options options;
@@ -997,7 +997,6 @@ void TestHalfBlockCopy() {
   CHECK_GE(onecopy_adds + 1, delta0.AddedBytes());
 
   CHECK_EQ(onecopy_adds, delta1.AddedBytes());
-  // XPR(NT "0=%zu 1=%zu\n", delta0.AddedBytes(), delta1.AddedBytes());
 }
 
 void FourWayMergeTest(const FileSpec &spec0,
@@ -1200,6 +1199,44 @@ void TestMergeCommand2() {
   }
 }
 
+void TestLastFrontierBlock() {
+  // This test constructs an input that can expose
+  // https://github.com/jmacd/xdelta/issues/188
+  // when run through the command-line with source via a FIFO.
+  // That is not tested here, but the test stays.
+  if (Constants::WINDOW_SIZE < XD3_ALLOCSIZE)
+    {
+      return;
+    }
+
+  MTRandom rand;
+  FileSpec spec0(&rand);
+  FileSpec spec1(&rand);
+  const xoff_t size = XD3_ALLOCSIZE * 64;  // == XD3_MINSRCWINSZ * 2
+  const xoff_t edit = XD3_ALLOCSIZE;
+
+  Options options;
+  options.encode_srcwin_maxsz = XD3_MINSRCWINSZ;
+  options.block_size = XD3_ALLOCSIZE;
+  options.window_size = XD3_MINSRCWINSZ;
+  options.size_known = false;
+
+  spec0.GenerateFixedSize(size);
+
+  ChangeList cl;
+
+  // Modify the 0th byte in order to induce indexing of subsequent
+  // bytes, but allow copying most of the file to keep the test fast.
+  cl.push_back(Change(Change::MODIFY, 1, edit * 31));
+  cl.push_back(Change(Change::COPYOVER, edit, edit * 31, edit * 63));
+
+  spec0.ModifyTo(ChangeListMutator(cl), &spec1);
+
+  Block noblock;
+  InMemoryEncodeDecode(spec0, spec1, &noblock, options);
+  InMemoryEncodeDecode(spec1, spec0, &noblock, options);
+}
+
 };  // class Regtest<Constants>
 
 #define TEST(x) XPR(NTR #x "...\n"); regtest.x()
@@ -1232,6 +1269,7 @@ void MainTest() {
   TEST(TestCopyFromEnd);
   TEST(TestNonBlocking);
   TEST(TestHalfBlockCopy);
+  TEST(TestLastFrontierBlock);
   TEST(TestMergeCommand1);
   TEST(TestMergeCommand2);
 }