Load the GL_KHR_debug entry points and log messages they produce.

gpu/command_buffer/service/gl_utils.cc

Index: gpu/command_buffer/service/gl_utils.cc
diff --git a/gpu/command_buffer/service/gl_utils.cc b/gpu/command_buffer/service/gl_utils.cc
index 16ef4548cb6a991192c71935b8d5524af55fa764..d5f663f307a58422082cc0f96ef0b441fed83262 100644
--- a/gpu/command_buffer/service/gl_utils.cc
+++ b/gpu/command_buffer/service/gl_utils.cc
@@ -12,6 +12,63 @@
 namespace gpu {
 namespace gles2 {
 
+namespace {
+const char* GetDebugSourceString(GLenum source) {
+  switch (source) {
+    case GL_DEBUG_SOURCE_API:
+      return "OpenGL";
+    case GL_DEBUG_SOURCE_WINDOW_SYSTEM:
+      return "Window System";
+    case GL_DEBUG_SOURCE_SHADER_COMPILER:
+      return "Shader Compiler";
+    case GL_DEBUG_SOURCE_THIRD_PARTY:
+      return "Third Party";
+    case GL_DEBUG_SOURCE_APPLICATION:
+      return "Application";
+    case GL_DEBUG_SOURCE_OTHER:
+      return "Other";
+    default:
+      return "UNKNOWN";
+  }
+}
+
+const char* GetDebugTypeString(GLenum type) {
+  switch (type) {
+    case GL_DEBUG_TYPE_ERROR:
+      return "Error";
+    case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
+      return "Deprecated behavior";
+    case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
+      return "Undefined behavior";
+    case GL_DEBUG_TYPE_PORTABILITY:
+      return "Portability";
+    case GL_DEBUG_TYPE_PERFORMANCE:
+      return "Performance";
+    case GL_DEBUG_TYPE_OTHER:
+      return "Other";
+    case GL_DEBUG_TYPE_MARKER:
+      return "Marker";
+    default:
+      return "UNKNOWN";
+  }
+}
+
+const char* GetDebugSeverityString(GLenum severity) {
+  switch (severity) {
+    case GL_DEBUG_SEVERITY_HIGH:
+      return "High";
+    case GL_DEBUG_SEVERITY_MEDIUM:
+      return "Medium";
+    case GL_DEBUG_SEVERITY_LOW:
+      return "Low";
+    case GL_DEBUG_SEVERITY_NOTIFICATION:
+      return "Notification";
+    default:
+      return "UNKNOWN";
+  }
+}
+}
+
 std::vector<int> GetAllGLErrors() {
   int gl_errors[] = {
     GL_NO_ERROR,
@@ -184,5 +241,34 @@ bool CheckUniqueAndNonNullIds(GLsizei n, const GLuint* client_ids) {
          (unique_ids.find(0) == unique_ids.end());
 }
 
+void APIENTRY LogGLDebugMessage(GLenum source,
+                                GLenum type,
+                                GLuint id,
+                                GLenum severity,
+                                GLsizei length,
+                                const GLchar* message,
+                                GLvoid* user_param) {
+  LOG(ERROR) << "GL Driver Message (" << GetDebugSourceString(source) << ", "
+             << GetDebugTypeString(type) << ", " << id << ", "
+             << GetDebugSeverityString(severity) << "): " << message;
+}
+
+void InitializeGLDebugLogging() {
+  glEnable(GL_DEBUG_OUTPUT);
+  glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
+
+  // Enable logging of medium and high severity messages
+  glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_HIGH, 0,
+                        nullptr, GL_TRUE);
+  glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_MEDIUM, 0,
+                        nullptr, GL_TRUE);
+  glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_LOW, 0,
+                        nullptr, GL_FALSE);
+  glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE,
+                        GL_DEBUG_SEVERITY_NOTIFICATION, 0, nullptr, GL_FALSE);
+
+  glDebugMessageCallback(&LogGLDebugMessage, nullptr);
+}
+
 }  // namespace gles2
 }  // namespace gpu