Almost there...



git-svn-id: svn://chrome-svn/chromeos/trunk@24 06c00378-0e64-4dae-be16-12b19f9950a1
diff --git a/decompressing_file_writer_unittest.cc b/decompressing_file_writer_unittest.cc
new file mode 100644
index 0000000..1d689e7
--- /dev/null
+++ b/decompressing_file_writer_unittest.cc
@@ -0,0 +1,107 @@
+// Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <string.h>
+#include <unistd.h>
+#include <string>
+#include <vector>
+#include <gtest/gtest.h>
+#include "update_engine/decompressing_file_writer.h"
+#include "update_engine/mock_file_writer.h"
+#include "update_engine/test_utils.h"
+
+using std::string;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+class GzipDecompressingFileWriterTest : public ::testing::Test { };
+
+TEST(GzipDecompressingFileWriterTest, SimpleTest) {
+  MockFileWriter mock_file_writer;
+  GzipDecompressingFileWriter decompressing_file_writer(&mock_file_writer);
+
+  // Here is the shell magic to include binary file in C source:
+  // hexdump -v -e '" " 12/1 "0x%02x, " "\n"' $FILENAME
+  // | sed -e '$s/0x  ,//g' -e 's/^/ /g' | awk
+  // 'BEGIN { print "unsigned char file[] = {" } END { print "};" } { print }'
+
+  // uncompressed, contains just 3 bytes: "hi\n"
+  unsigned char hi_txt_gz[] = {
+    0x1f, 0x8b, 0x08, 0x08, 0x62, 0xf5, 0x8a, 0x4a,
+    0x02, 0x03, 0x68, 0x69, 0x2e, 0x74, 0x78, 0x74,
+    0x00, 0xcb, 0xc8, 0xe4, 0x02, 0x00, 0x7a, 0x7a,
+    0x6f, 0xed, 0x03, 0x00, 0x00, 0x00,
+  };
+  char hi[] = "hi\n";
+  vector<char> hi_vector(hi, hi + strlen(hi));
+
+  const string path("unused");
+  ASSERT_EQ(0, decompressing_file_writer.Open(
+      path.c_str(), O_CREAT | O_LARGEFILE | O_TRUNC | O_WRONLY, 0644));
+  ASSERT_EQ(sizeof(hi_txt_gz),
+            decompressing_file_writer.Write(hi_txt_gz, sizeof(hi_txt_gz)));
+  ASSERT_EQ(hi_vector.size(), mock_file_writer.bytes().size());
+  for (unsigned int i = 0; i < hi_vector.size(); i++) {
+    EXPECT_EQ(hi_vector[i], mock_file_writer.bytes()[i]) << "i = " << i;
+  }
+}
+
+TEST(GzipDecompressingFileWriterTest, IllegalStreamTest) {
+  MockFileWriter mock_file_writer;
+  GzipDecompressingFileWriter decompressing_file_writer(&mock_file_writer);
+
+  const string path("unused");
+  ASSERT_EQ(0, decompressing_file_writer.Open(
+      path.c_str(), O_CREAT | O_LARGEFILE | O_TRUNC | O_WRONLY, 0644));
+  EXPECT_EQ(0, decompressing_file_writer.Write("\0\0\0\0\0\0\0\0", 8));
+  EXPECT_EQ(0, mock_file_writer.bytes().size());
+}
+
+TEST(GzipDecompressingFileWriterTest, LargeTest) {
+  const string kPath("/tmp/GzipDecompressingFileWriterTest");
+  const string kPathgz(kPath + ".gz");
+  // First, generate some data, say 10 megs:
+  DirectFileWriter uncompressed_file;
+  const char* k10bytes = "0123456789";
+  const unsigned int k10bytesSize = 10;
+  const unsigned int kUncompressedFileSize = strlen(k10bytes) * 1024 * 1024;
+  uncompressed_file.Open(kPath.c_str(),
+                         O_CREAT | O_LARGEFILE | O_TRUNC | O_WRONLY, 0644);
+  for (unsigned int i = 0; i < kUncompressedFileSize / k10bytesSize; i++) {
+    ASSERT_EQ(k10bytesSize, uncompressed_file.Write("0123456789", 10));
+  }
+  uncompressed_file.Close();
+
+  // compress the file
+  system((string("cat ") + kPath + " | gzip > " + kPathgz).c_str());
+
+  // Now read the compressed file and put it into a DecompressingFileWriter
+  MockFileWriter mock_file_writer;
+  GzipDecompressingFileWriter decompressing_file_writer(&mock_file_writer);
+
+  const string path("unused");
+  ASSERT_EQ(0, decompressing_file_writer.Open(
+      path.c_str(), O_CREAT | O_LARGEFILE | O_TRUNC | O_WRONLY, 0644));
+
+  // Open compressed file for reading:
+  int fd_in = open(kPathgz.c_str(), O_LARGEFILE | O_RDONLY, 0);
+  ASSERT_GE(fd_in, 0);
+  char buf[100];
+  int sz;
+  while ((sz = read(fd_in, buf, sizeof(buf))) > 0) {
+    decompressing_file_writer.Write(buf, sz);
+  }
+  close(fd_in);
+  decompressing_file_writer.Close();
+
+  ASSERT_EQ(kUncompressedFileSize, mock_file_writer.bytes().size());
+  for (unsigned int i = 0; i < kUncompressedFileSize; i++) {
+    ASSERT_EQ(mock_file_writer.bytes()[i], '0' + (i % 10)) << "i = " << i;
+  }
+  unlink(kPath.c_str());
+  unlink(kPathgz.c_str());
+}
+
+}  // namespace chromeos_update_engine