Re-land r92885, which was reverted in r92891.

ppapi/c/dev/ppb_graphics_3d_trusted_dev.h

+// Copyright (c) 2011 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.
+
+#ifndef PPAPI_C_DEV_PPB_GRAPHICS_3D_TRUSTED_DEV_H_
+#define PPAPI_C_DEV_PPB_GRAPHICS_3D_TRUSTED_DEV_H_
+
+#include "ppapi/c/pp_bool.h"
+#include "ppapi/c/pp_instance.h"
+#include "ppapi/c/pp_resource.h"
+#include "ppapi/c/pp_stdint.h"
+
+#define PPB_GRAPHICS_3D_TRUSTED_DEV_INTERFACE_0_1 \
+    "PPB_Graphics3DTrusted(Dev);0.1"
+#define PPB_GRAPHICS_3D_TRUSTED_DEV_INTERFACE \
+    PPB_GRAPHICS_3D_TRUSTED_DEV_INTERFACE_0_1
+
+typedef enum {
+  PPB_GRAPHICS3D_TRUSTED_ERROR_OK,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_GENERICERROR,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_INVALIDARGUMENTS,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_INVALIDSIZE,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_LOSTCONTEXT,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_OUTOFBOUNDS,
+  PPB_GRAPHICS3D_TRUSTED_ERROR_UNKNOWNCOMMAND
+} PPB_Graphics3DTrustedError;
+
+struct PP_Graphics3DTrustedState {
+  // Size of the command buffer in command buffer entries.
+  int32_t num_entries;
+
+  // The offset (in entries) from which the reader is reading.
+  int32_t get_offset;
+
+  // The offset (in entries) at which the writer is writing.
+  int32_t put_offset;
+
+  // The current token value. This is used by the writer to defer
+  // changes to shared memory objects until the reader has reached a certain
+  // point in the command buffer. The reader is responsible for updating the
+  // token value, for example in response to an asynchronous set token command
+  // embedded in the command buffer. The default token value is zero.
+  int32_t token;
+
+  // Error status.
+  PPB_Graphics3DTrustedError error;
+
+  // Generation index of this state. The generation index is incremented every
+  // time a new state is retrieved from the command processor, so that
+  // consistency can be kept even if IPC messages are processed out-of-order.
+  uint32_t generation;
+};
+
+struct PPB_Graphics3DTrusted_Dev {
+  // Creates a raw Graphics3D resource. A raw Graphics3D is intended to be used
+  // with the trusted interface, through the command buffer (for proxying).
+  PP_Resource (*CreateRaw)(PP_Instance instance_id,
+                           PP_Config3D_Dev config,
+                           PP_Resource share_context,
+                           const int32_t* attrib_list);
+
+  // Initializes the command buffer with the given size.
+  PP_Bool (*InitCommandBuffer)(PP_Resource context_id, int32_t size);
+
+  // Gets the ring buffer for the command buffer.
+  PP_Bool (*GetRingBuffer)(PP_Resource context_id,
+                           int* shm_handle,
+                           uint32_t* shm_size);
+
+  // Returns the current state.
+  struct PP_Graphics3DTrustedState (*GetState)(PP_Resource context);
+
+  // Create a transfer buffer and return a handle that uniquely
+  // identifies it or -1 on error.
+  int32_t (*CreateTransferBuffer)(PP_Resource context, uint32_t size);
+
+  // Destroy a transfer buffer and recycle the handle.
+  PP_Bool (*DestroyTransferBuffer)(PP_Resource context, int32_t id);
+
+  // Get the transfer buffer associated with a handle.
+  PP_Bool (*GetTransferBuffer)(PP_Resource context,
+                               int32_t id,
+                               int* shm_handle,
+                               uint32_t* shm_size);
+
+  // The writer calls this to update its put offset.
+  PP_Bool (*Flush)(PP_Resource context, int32_t put_offset);
+
+  // The writer calls this to update its put offset. This function returns the
+  // reader's most recent get offset. Does not return until after the put offset
+  // change callback has been invoked.
+  struct PP_Graphics3DTrustedState (*FlushSync)(PP_Resource context,
+                                                int32_t put_offset);
+
+  // Like FlushSync, but returns before processing commands if the get offset is
+  // different than last_known_get. Allows synchronization with the command
+  // processor without forcing immediate command execution.
+  struct PP_Graphics3DTrustedState (*FlushSyncFast)(PP_Resource context,
+                                                    int32_t put_offset,
+                                                    int32_t last_known_get);
+};
+
+#endif  // PPAPI_C_DEV_PPB_GRAPHICS_3D_TRUSTED_DEV_H_
+