Missed new files in last commit

Review URL: http://codereview.chromium.org/465067


git-svn-id: svn://chrome-svn/chromeos/trunk@336 06c00378-0e64-4dae-be16-12b19f9950a1

1 files changed, 185 insertions, 0 deletions

diff --git a/gzip.cc b/gzip.cc
new file mode 100644
index 00000000..96437248
--- /dev/null
+++ b/gzip.cc
@@ -0,0 +1,185 @@
+// Copyright (c) 2009 The Chromium 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 "update_engine/gzip.h"
+#include <stdlib.h>
+#include <algorithm>
+#include <zlib.h>
+#include "chromeos/obsolete_logging.h"
+#include "update_engine/utils.h"
+
+using std::max;
+using std::string;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+bool GzipDecompressData(const char* const in, const size_t in_size,
+                        char** out, size_t* out_size) {
+  if (in_size == 0) {
+    // malloc(0) may legally return NULL, so do malloc(1)
+    *out = reinterpret_cast<char*>(malloc(1));
+    *out_size = 0;
+    return true;
+  }
+  TEST_AND_RETURN_FALSE(out);
+  TEST_AND_RETURN_FALSE(out_size);
+  z_stream stream;
+  memset(&stream, 0, sizeof(stream));
+  TEST_AND_RETURN_FALSE(inflateInit2(&stream, 16 + MAX_WBITS) == Z_OK);
+
+  // guess that output will be roughly double the input size
+  *out_size = in_size * 2;
+  *out = reinterpret_cast<char*>(malloc(*out_size));
+  TEST_AND_RETURN_FALSE(*out);
+
+  // TODO(adlr): ensure that this const_cast is safe.
+  stream.next_in = const_cast<Bytef*>(reinterpret_cast<const Bytef*>(in));
+  stream.avail_in = in_size;
+  stream.next_out = reinterpret_cast<Bytef*>(*out);
+  stream.avail_out = *out_size;
+  for (;;) {
+    int rc = inflate(&stream, Z_FINISH);
+    switch (rc) {
+      case Z_STREAM_END: {
+        *out_size = reinterpret_cast<char*>(stream.next_out) - (*out);
+        TEST_AND_RETURN_FALSE(inflateEnd(&stream) == Z_OK);
+        return true;
+      }
+      case Z_OK:  // fall through
+      case Z_BUF_ERROR: {
+        // allocate more space
+        ptrdiff_t out_length =
+            reinterpret_cast<char*>(stream.next_out) - (*out);
+        *out_size *= 2;
+        char* new_out = reinterpret_cast<char*>(realloc(*out, *out_size));
+        if (!new_out) {
+          free(*out);
+          return false;
+        }
+        *out = new_out;
+        stream.next_out = reinterpret_cast<Bytef*>((*out) + out_length);
+        stream.avail_out = (*out_size) - out_length;
+        break;
+      }
+      default:
+        LOG(INFO) << "Unknown inflate() return value: " << rc;
+        if (stream.msg)
+          LOG(INFO) << " message: " << stream.msg;
+        free(*out);
+        return false;
+    }
+  }
+}
+
+bool GzipCompressData(const char* const in, const size_t in_size,
+                      char** out, size_t* out_size) {
+  if (in_size == 0) {
+    // malloc(0) may legally return NULL, so do malloc(1)
+    *out = reinterpret_cast<char*>(malloc(1));
+    *out_size = 0;
+    return true;
+  }
+  TEST_AND_RETURN_FALSE(out);
+  TEST_AND_RETURN_FALSE(out_size);
+  z_stream stream;
+  memset(&stream, 0, sizeof(stream));
+  TEST_AND_RETURN_FALSE(deflateInit2(&stream,
+                                      Z_BEST_COMPRESSION,
+                                      Z_DEFLATED,
+                                      16 + MAX_WBITS,
+                                      9,  // most memory used/best compression
+                                      Z_DEFAULT_STRATEGY) == Z_OK);
+
+  // guess that output will be roughly half the input size
+  *out_size = max(1U, in_size / 2);
+  *out = reinterpret_cast<char*>(malloc(*out_size));
+  TEST_AND_RETURN_FALSE(*out);
+
+  // TODO(adlr): ensure that this const_cast is safe.
+  stream.next_in = const_cast<Bytef*>(reinterpret_cast<const Bytef*>(in));
+  stream.avail_in = in_size;
+  stream.next_out = reinterpret_cast<Bytef*>(*out);
+  stream.avail_out = *out_size;
+  for (;;) {
+    int rc = deflate(&stream, Z_FINISH);
+    switch (rc) {
+      case Z_STREAM_END: {
+        *out_size = reinterpret_cast<char*>(stream.next_out) - (*out);
+        TEST_AND_RETURN_FALSE(deflateEnd(&stream) == Z_OK);
+        return true;
+      }
+      case Z_OK:  // fall through
+      case Z_BUF_ERROR: {
+        // allocate more space
+        ptrdiff_t out_length =
+            reinterpret_cast<char*>(stream.next_out) - (*out);
+        *out_size *= 2;
+        char* new_out = reinterpret_cast<char*>(realloc(*out, *out_size));
+        if (!new_out) {
+          free(*out);
+          return false;
+        }
+        *out = new_out;
+        stream.next_out = reinterpret_cast<Bytef*>((*out) + out_length);
+        stream.avail_out = (*out_size) - out_length;
+        break;
+      }
+      default:
+        LOG(INFO) << "Unknown defalate() return value: " << rc;
+        if (stream.msg)
+          LOG(INFO) << " message: " << stream.msg;
+        free(*out);
+        return false;
+    }
+  }
+}
+
+bool GzipDecompress(const std::vector<char>& in, std::vector<char>* out) {
+  TEST_AND_RETURN_FALSE(out);
+  char* out_buf;
+  size_t out_size;
+  TEST_AND_RETURN_FALSE(GzipDecompressData(&in[0], in.size(),
+                                            &out_buf, &out_size));
+  out->insert(out->end(), out_buf, out_buf + out_size);
+  free(out_buf);
+  return true;
+}
+
+bool GzipCompress(const std::vector<char>& in, std::vector<char>* out) {
+  TEST_AND_RETURN_FALSE(out);
+  char* out_buf;
+  size_t out_size;
+  TEST_AND_RETURN_FALSE(GzipCompressData(&in[0], in.size(),
+                                          &out_buf, &out_size));
+  out->insert(out->end(), out_buf, out_buf + out_size);
+  free(out_buf);
+  return true;
+}
+
+bool GzipCompressString(const std::string& str,
+                        std::vector<char>* out) {
+  TEST_AND_RETURN_FALSE(out);
+  char* out_buf;
+  size_t out_size;
+  TEST_AND_RETURN_FALSE(GzipCompressData(str.data(), str.size(),
+                                          &out_buf, &out_size));
+  out->insert(out->end(), out_buf, out_buf + out_size);
+  free(out_buf);
+  return true;
+}
+
+bool GzipDecompressString(const std::string& str,
+                          std::vector<char>* out) {
+  TEST_AND_RETURN_FALSE(out);
+  char* out_buf;
+  size_t out_size;
+  TEST_AND_RETURN_FALSE(GzipDecompressData(str.data(), str.size(),
+                                            &out_buf, &out_size));
+  out->insert(out->end(), out_buf, out_buf + out_size);
+  free(out_buf);
+  return true;
+}
+
+} // namespace chromeos_update_engine