Branched gpu process and command buffer code into Chrome tree. Fixed up paths and other minor changes to make it work in the Chrome tree. Will remove copy from O3D tree shortly. Only works in Windows currently.

TEST=none
BUG=none

Review URL: http://codereview.chromium.org/436017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@32952 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 110 insertions, 0 deletions

diff --git a/gpu/command_buffer/service/cmd_parser.cc b/gpu/command_buffer/service/cmd_parser.cc
new file mode 100644
index 0000000..019e7b2
--- /dev/null
+++ b/gpu/command_buffer/service/cmd_parser.cc
@@ -0,0 +1,110 @@
+/*
+ * 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.
+ */
+
+
+// This file contains the implementation of the command parser.
+
+#include "gpu/command_buffer/service/precompile.h"
+#include "gpu/command_buffer/service/cmd_parser.h"
+
+namespace command_buffer {
+
+CommandParser::CommandParser(void *shm_address,
+                             size_t shm_size,
+                             ptrdiff_t offset,
+                             size_t size,
+                             CommandBufferOffset start_get,
+                             AsyncAPIInterface *handler)
+    : get_(start_get),
+      put_(start_get),
+      handler_(handler) {
+  // check proper alignments.
+  DCHECK_EQ(0, (reinterpret_cast<intptr_t>(shm_address)) % 4);
+  DCHECK_EQ(0, offset % 4);
+  DCHECK_EQ(0u, size % 4);
+  // check that the command buffer fits into the memory buffer.
+  DCHECK_GE(shm_size, offset + size);
+  char * buffer_begin = static_cast<char *>(shm_address) + offset;
+  buffer_ = reinterpret_cast<CommandBufferEntry *>(buffer_begin);
+  entry_count_ = size / 4;
+}
+
+// Process one command, reading the header from the command buffer, and
+// forwarding the command index and the arguments to the handler.
+// Note that:
+// - validation needs to happen on a copy of the data (to avoid race
+// conditions). This function only validates the header, leaving the arguments
+// validation to the handler, so it can pass a reference to them.
+// - get_ is modified *after* the command has been executed.
+parse_error::ParseError CommandParser::ProcessCommand() {
+  CommandBufferOffset get = get_;
+  if (get == put_) return parse_error::kParseNoError;
+
+  CommandHeader header = buffer_[get].value_header;
+  if (header.size == 0) {
+    DLOG(INFO) << "Error: zero sized command in command buffer";
+    return parse_error::kParseInvalidSize;
+  }
+
+  if (header.size + get > entry_count_) {
+    DLOG(INFO) << "Error: get offset out of bounds";
+    return parse_error::kParseOutOfBounds;
+  }
+
+  parse_error::ParseError result = handler_->DoCommand(
+      header.command, header.size - 1, buffer_ + get);
+  // TODO(gman): If you want to log errors this is the best place to catch them.
+  //     It seems like we need an official way to turn on a debug mode and
+  //     get these errors.
+  if (result != parse_error::kParseNoError) {
+    ReportError(header.command, result);
+  }
+  get_ = (get + header.size) % entry_count_;
+  return result;
+}
+
+void CommandParser::ReportError(unsigned int command_id,
+                                parse_error::ParseError result) {
+  DLOG(INFO) << "Error: " << result << " for Command "
+             << handler_->GetCommandName(command_id);
+}
+
+// Processes all the commands, while the buffer is not empty. Stop if an error
+// is encountered.
+parse_error::ParseError CommandParser::ProcessAllCommands() {
+  while (!IsEmpty()) {
+    parse_error::ParseError error = ProcessCommand();
+    if (error) return error;
+  }
+  return parse_error::kParseNoError;
+}
+
+}  // namespace command_buffer