This is the O3D source tree's initial commit to the Chromium tree. It

is not built or referenced at all by the chrome build yet, and doesn't 
yet build in it's new home.  We'll change that shortly.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@17035 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 121 insertions, 0 deletions

diff --git a/o3d/import/cross/gz_decompressor.cc b/o3d/import/cross/gz_decompressor.cc
new file mode 100644
index 0000000..333a999
--- /dev/null
+++ b/o3d/import/cross/gz_decompressor.cc
@@ -0,0 +1,121 @@
+/*
+ * Copyright 2009, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+//
+// GzDecompressor decompresses a gzip compressed byte stream
+// calling the client's ProcessBytes() method with the uncompressed stream
+//
+
+#include "import/cross/gz_decompressor.h"
+
+#include <assert.h>
+#include "import/cross/memory_stream.h"
+
+const size_t kChunkSize = 16384;
+
+namespace o3d {
+
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+GzDecompressor::GzDecompressor(StreamProcessor *callback_client)
+    : callback_client_(callback_client) {
+  // Initialize inflate state
+  strm_.zalloc = Z_NULL;
+  strm_.zfree = Z_NULL;
+  strm_.opaque = Z_NULL;
+  strm_.avail_in = 0;
+  strm_.next_in = Z_NULL;
+
+  // Store this, so we can later check if it's OK to start processing
+  init_result_ = inflateInit2(&strm_, 31);
+}
+
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+GzDecompressor::~GzDecompressor() {
+  inflateEnd(&strm_);
+}
+
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+int GzDecompressor::ProcessBytes(MemoryReadStream *stream,
+                                 size_t bytes_to_process) {
+  // Don't even bother trying if we didn't get initialized properly
+  if (init_result_ != Z_OK) return init_result_;
+
+  uint8 out[kChunkSize];
+  int result;
+  size_t have;
+
+  // Don't try to read more than our stream has
+  int remaining = stream->GetRemainingByteCount();
+  if (bytes_to_process > remaining) {
+    return Z_STREAM_ERROR;  // could have our own error code, but good enough...
+  }
+
+  // Use direct memory access on the MemoryStream object
+  strm_.avail_in = bytes_to_process;
+  strm_.next_in = const_cast<uint8*>(stream->GetDirectMemoryPointer());
+  stream->Skip(bytes_to_process);
+
+  // Run inflate() on input until output buffer not full
+  do {
+    strm_.avail_out = kChunkSize;
+    strm_.next_out = out;
+
+    result = inflate(&strm_, Z_NO_FLUSH);
+
+    // error check here - return error codes if necessary
+    assert(result != Z_STREAM_ERROR);  /* state not clobbered */
+    switch (result) {
+      case Z_NEED_DICT:
+        result = Z_DATA_ERROR;     /* and fall through */
+
+      case Z_DATA_ERROR:
+      case Z_MEM_ERROR:
+        return result;
+    }
+
+    have = kChunkSize - strm_.avail_out;
+
+    // Callback with the decompressed byte stream
+    MemoryReadStream decompressed_stream(out, have);
+    if (callback_client_) {
+      int client_result =
+          callback_client_->ProcessBytes(&decompressed_stream, have);
+      if (client_result != 0) {
+        return client_result;  // propagate callback errors
+      }
+    }
+  } while (strm_.avail_out == 0);
+
+  return result;
+}
+
+}  // namespace o3d