1 files changed, 107 insertions, 0 deletions
diff --git a/chromium/gpu/command_buffer/service/cmd_parser.cc b/chromium/gpu/command_buffer/service/cmd_parser.cc
new file mode 100644
index 00000000000..0ca1e616a86
--- /dev/null
+++ b/chromium/gpu/command_buffer/service/cmd_parser.cc
@@ -0,0 +1,107 @@
+// Copyright (c) 2012 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.
+
+// This file contains the implementation of the command parser.
+
+#include "gpu/command_buffer/service/cmd_parser.h"
+
+#include "base/logging.h"
+#include "base/command_line.h"
+#include "base/debug/trace_event.h"
+#include "gpu/command_buffer/service/gpu_switches.h"
+
+namespace gpu {
+
+CommandParser::CommandParser(AsyncAPIInterface* handler)
+    : get_(0),
+      put_(0),
+      buffer_(NULL),
+      entry_count_(0),
+      handler_(handler),
+      trace_gl_commands_(false) {
+  trace_gl_commands_ =
+      CommandLine::ForCurrentProcess()->HasSwitch(switches::kTraceGL);
+}
+
+void CommandParser::SetBuffer(
+    void* shm_address,
+    size_t shm_size,
+    ptrdiff_t offset,
+    size_t size) {
+  // 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);
+  get_ = 0;
+  put_ = 0;
+  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.
+error::Error CommandParser::ProcessCommand() {
+  CommandBufferOffset get = get_;
+  if (get == put_)
+    return error::kNoError;
+
+  CommandHeader header = buffer_[get].value_header;
+  if (header.size == 0) {
+    DVLOG(1) << "Error: zero sized command in command buffer";
+    return error::kInvalidSize;
+  }
+
+  if (static_cast<int>(header.size) + get > entry_count_) {
+    DVLOG(1) << "Error: get offset out of bounds";
+    return error::kOutOfBounds;
+  }
+
+  if (trace_gl_commands_)
+    TRACE_EVENT_BEGIN0("cb_command", handler_->GetCommandName(header.command));
+
+  error::Error 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 (error::IsError(result)) {
+    ReportError(header.command, result);
+  }
+
+  // If get was not set somewhere else advance it.
+  if (get == get_ && result != error::kDeferCommandUntilLater)
+    get_ = (get + header.size) % entry_count_;
+
+  if (trace_gl_commands_)
+    TRACE_EVENT_END0("cb_command", handler_->GetCommandName(header.command));
+  return result;
+}
+
+void CommandParser::ReportError(unsigned int command_id,
+                                error::Error result) {
+  DVLOG(1) << "Error: " << result << " for Command "
+           << handler_->GetCommandName(command_id);
+}
+
+// Processes all the commands, while the buffer is not empty. Stop if an error
+// is encountered.
+error::Error CommandParser::ProcessAllCommands() {
+  while (!IsEmpty()) {
+    error::Error error = ProcessCommand();
+    if (error)
+      return error;
+  }
+  return error::kNoError;
+}
+
+}  // namespace gpu