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-rw-r--r--remoting/client/plugin/compression.cc114
1 files changed, 114 insertions, 0 deletions
diff --git a/remoting/client/plugin/compression.cc b/remoting/client/plugin/compression.cc
new file mode 100644
index 0000000..4e89727
--- /dev/null
+++ b/remoting/client/plugin/compression.cc
@@ -0,0 +1,114 @@
+// Copyright (c) 2010 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 "remoting/client/plugin/compression.h"
+
+#include <assert.h>
+
+namespace remoting {
+
+static const int kZLIB_CHUNK = 256 * 1024;
+
+ZCompressor::ZCompressor() {
+ stream_.zalloc = Z_NULL;
+ stream_.zfree = Z_NULL;
+ stream_.opaque = Z_NULL;
+
+ deflateInit(&stream_, Z_BEST_SPEED);
+}
+
+void ZCompressor::WriteInternal(char* buffer, int size, int flush) {
+ stream_.avail_in = size;
+ stream_.next_in = reinterpret_cast<Bytef*>(buffer);
+
+ // Expand the internal buffer.
+ while (true) {
+ int last_size = buffer_.size();
+ buffer_.resize(last_size + kZLIB_CHUNK);
+ stream_.avail_out = kZLIB_CHUNK;
+ stream_.next_out = reinterpret_cast<Bytef*>(&buffer_[last_size]);
+ int ret = deflate(&stream_, flush);
+ assert(ret != Z_STREAM_ERROR);
+
+ // Shrink the size of the vector. It doesn't alter the capacity.
+ int compressed = kZLIB_CHUNK - stream_.avail_out;
+ buffer_.resize(last_size + compressed);
+ if (!compressed)
+ break;
+ }
+}
+
+void ZCompressor::Write(char* buffer, int size) {
+ WriteInternal(buffer, size, Z_NO_FLUSH);
+}
+
+void ZCompressor::Flush() {
+ WriteInternal(NULL, 0, Z_FINISH);
+ deflateEnd(&stream_);
+}
+
+int ZCompressor::GetCompressedSize() {
+ return buffer_.size();
+}
+
+char* ZCompressor::GetCompressedData() {
+ return &buffer_[0];
+}
+
+int ZCompressor::GetRawSize() {
+ // I don't care about this.
+ return 0;
+}
+
+ZDecompressor::ZDecompressor() {
+ stream_.zalloc = Z_NULL;
+ stream_.zfree = Z_NULL;
+ stream_.opaque = Z_NULL;
+ stream_.avail_in = 0;
+ stream_.next_in = Z_NULL;
+
+ inflateInit(&stream_);
+}
+
+void ZDecompressor::WriteInternal(char* buffer, int size, int flush) {
+ stream_.avail_in = size;
+ stream_.next_in = reinterpret_cast<Bytef*>(buffer);
+
+ while (true) {
+ int last_size = buffer_.size();
+ buffer_.resize(last_size + kZLIB_CHUNK);
+ stream_.avail_out = kZLIB_CHUNK;
+ stream_.next_out = reinterpret_cast<Bytef*>(&buffer_[last_size]);
+ int ret = inflate(&stream_, flush);
+ assert(ret != Z_STREAM_ERROR);
+
+ // Shrink the size of the vector. It doesn't alter the capacity.
+ int decompressed = kZLIB_CHUNK - stream_.avail_out;
+ buffer_.resize(last_size + decompressed);
+ if (!decompressed)
+ break;
+ }
+}
+
+void ZDecompressor::Write(char* buffer, int size) {
+ WriteInternal(buffer, size, Z_NO_FLUSH);
+}
+
+void ZDecompressor::Flush() {
+ inflateEnd(&stream_);
+}
+
+char* ZDecompressor::GetRawData() {
+ return &buffer_[0];
+}
+
+int ZDecompressor::GetRawSize() {
+ return buffer_.size();
+}
+
+int ZDecompressor::GetCompressedSize() {
+ // I don't care.
+}
+
+} // namespace remoting