Pepper WebSocket API: Implement new design Chrome IPC

ppapi/proxy/websocket_resource.cc

+// 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.
+
+#include "ppapi/proxy/websocket_resource.h"
+
+#include <set>
+#include <vector>
+
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/shared_impl/ppapi_globals.h"
+#include "ppapi/shared_impl/var.h"
+#include "ppapi/shared_impl/var_tracker.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebSocket.h"
+
+namespace {
+
+const uint32_t kMaxReasonSizeInBytes = 123;
+const size_t kBaseFramingOverhead = 2;
+const size_t kMaskingKeyLength = 4;
+const size_t kMinimumPayloadSizeWithTwoByteExtendedPayloadLength = 126;
+const size_t kMinimumPayloadSizeWithEightByteExtendedPayloadLength = 0x10000;
+
+uint64_t SaturateAdd(uint64_t a, uint64_t b) {
+  if (kuint64max - a < b)
+    return kuint64max;
+  return a + b;
+}
+
+uint64_t GetFrameSize(uint64_t payload_size) {
+  uint64_t overhead = kBaseFramingOverhead + kMaskingKeyLength;
+  if (payload_size > kMinimumPayloadSizeWithEightByteExtendedPayloadLength)
+    overhead += 8;
+  else if (payload_size > kMinimumPayloadSizeWithTwoByteExtendedPayloadLength)
+    overhead += 2;
+  return SaturateAdd(payload_size, overhead);
+}
+
+bool InValidStateToReceive(PP_WebSocketReadyState state) {
+  return state == PP_WEBSOCKETREADYSTATE_OPEN ||
+         state == PP_WEBSOCKETREADYSTATE_CLOSING;
+}
+
+}  // namespace
+
+
+namespace ppapi {
+namespace proxy {
+
+WebSocketResource::WebSocketResource(Connection connection,
+                                     PP_Instance instance)
+    : PluginResource(connection, instance),
+      state_(PP_WEBSOCKETREADYSTATE_INVALID),
+      error_was_received_(false),
+      receive_callback_var_(NULL),
+      empty_string_(new StringVar("", 0)),

[brettw, 2012/10/03 20:30:24]

Can you use "new StringVar(std::string())," here instead?

[Takashi Toyoshima, 2012/10/05 07:35:01]

Done.

+      close_code_(0),
+      close_reason_(NULL),
+      close_was_clean_(PP_FALSE),
+      extensions_(NULL),
+      protocol_(NULL),
+      url_(NULL),
+      buffered_amount_(0),
+      buffered_amount_after_close_(0) {
+}
+
+WebSocketResource::~WebSocketResource() {
+}
+
+thunk::PPB_WebSocket_API* WebSocketResource::AsPPB_WebSocket_API() {
+  return this;
+}
+
+int32_t WebSocketResource::Connect(
+    const PP_Var& url,
+    const PP_Var protocols[],
+    uint32_t protocol_count,
+    scoped_refptr<TrackedCallback> callback) {
+  if (TrackedCallback::IsPending(connect_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  // Connect() can be called at most once.
+  if (state_ != PP_WEBSOCKETREADYSTATE_INVALID)
+    return PP_ERROR_INPROGRESS;
+  state_ = PP_WEBSOCKETREADYSTATE_CLOSED;
+
+  // Get the URL.
+  scoped_refptr<StringVar> url_string = StringVar::FromPPVar(url);
+  if (!url_string)
+    return PP_ERROR_BADARGUMENT;
+
+  // Get the protocols.
+  std::set<std::string> protocol_set;
+  std::vector<std::string> protocol_strings;
+  protocol_strings.reserve(protocol_count);
+  for (uint32_t i = 0; i < protocol_count; ++i) {
+    scoped_refptr<StringVar> protocol(StringVar::FromPPVar(protocols[i]));
+
+    // Check invalid and empty entries.
+    if (!protocol || !protocol->value().length())
+      return PP_ERROR_BADARGUMENT;
+
+    // Check duplicated protocol entries.
+    if (protocol_set.find(protocol->value()) != protocol_set.end())
+      return PP_ERROR_BADARGUMENT;
+    protocol_set.insert(protocol->value());
+
+    protocol_strings.push_back(protocol->value());
+  }
+
+  // Install callback.
+  connect_callback_ = callback;
+
+  // Create remote host in the renderer, then request to check the URL and
+  // establish the connection.
+  state_ = PP_WEBSOCKETREADYSTATE_CONNECTING;
+  SendCreateToRenderer(PpapiHostMsg_WebSocket_Create());
+  CallRenderer(PpapiHostMsg_WebSocket_Connect(url_string->value(),
+                                              protocol_strings));
+
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t WebSocketResource::Close(uint16_t code,
+                                 const PP_Var& reason,
+                                 scoped_refptr<TrackedCallback> callback) {
+  if (TrackedCallback::IsPending(close_callback_))
+    return PP_ERROR_INPROGRESS;
+  if (state_ == PP_WEBSOCKETREADYSTATE_INVALID)
+    return PP_ERROR_FAILED;
+
+  // Validate |code| and |reason|.
+  scoped_refptr<StringVar> reason_string_var;
+  std::string reason_string;
+  WebKit::WebSocket::CloseEventCode event_code =
+      static_cast<WebKit::WebSocket::CloseEventCode>(code);
+  if (code == PP_WEBSOCKETSTATUSCODE_NOT_SPECIFIED) {
+    // PP_WEBSOCKETSTATUSCODE_NOT_SPECIFIED and CloseEventCodeNotSpecified are
+    // assigned to different values. A conversion is needed if
+    // PP_WEBSOCKETSTATUSCODE_NOT_SPECIFIED is specified.
+    event_code = WebKit::WebSocket::CloseEventCodeNotSpecified;
+  } else {
+    if (!(code == PP_WEBSOCKETSTATUSCODE_NORMAL_CLOSURE ||
+        (PP_WEBSOCKETSTATUSCODE_USER_REGISTERED_MIN <= code &&
+        code <= PP_WEBSOCKETSTATUSCODE_USER_PRIVATE_MAX)))
+      // RFC 6455 limits applications to use reserved connection close code in
+      // section 7.4.2.. The WebSocket API (http://www.w3.org/TR/websockets/)
+      // defines this out of range error as InvalidAccessError in JavaScript.
+      return PP_ERROR_NOACCESS;
+
+    // |reason| must be ignored if it is PP_VARTYPE_UNDEFINED or |code| is
+    // PP_WEBSOCKETSTATUSCODE_NOT_SPECIFIED.
+    if (reason.type != PP_VARTYPE_UNDEFINED) {
+      // Validate |reason|.
+      reason_string_var = StringVar::FromPPVar(reason);
+      if (!reason_string_var ||
+          reason_string_var->value().size() > kMaxReasonSizeInBytes)
+        return PP_ERROR_BADARGUMENT;
+      reason_string = reason_string_var->value();
+    }
+  }
+
+  // Check state.
+  if (state_ == PP_WEBSOCKETREADYSTATE_CLOSING)
+    return PP_ERROR_INPROGRESS;
+  if (state_ == PP_WEBSOCKETREADYSTATE_CLOSED)
+    return PP_OK;
+
+  // Install |callback|.
+  close_callback_ = callback;
+
+  // Abort ongoing connect.
+  if (connect_callback_) {
+    state_ = PP_WEBSOCKETREADYSTATE_CLOSING;
+    // Need to do a "Post" to avoid reentering the plugin.
+    connect_callback_->PostAbort();
+    connect_callback_ = NULL;
+    CallRenderer(PpapiHostMsg_WebSocket_Fail(
+        "WebSocket was closed before the connection was established."));
+    return PP_OK_COMPLETIONPENDING;
+  }
+
+  // Abort ongoing receive.
+  if (receive_callback_) {
+    receive_callback_var_ = NULL;
+    // Need to do a "Post" to avoid reentering the plugin.
+    receive_callback_->PostAbort();
+    receive_callback_ = NULL;
+  }
+
+  // Close connection.
+  state_ = PP_WEBSOCKETREADYSTATE_CLOSING;
+  CallRenderer(PpapiHostMsg_WebSocket_Close(static_cast<int32_t>(event_code),
+                                            reason_string));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t WebSocketResource::ReceiveMessage(
+    PP_Var* message,
+    scoped_refptr<TrackedCallback> callback) {
+  if (TrackedCallback::IsPending(receive_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  // Check state.
+  if (state_ == PP_WEBSOCKETREADYSTATE_INVALID ||
+      state_ == PP_WEBSOCKETREADYSTATE_CONNECTING)
+    return PP_ERROR_BADARGUMENT;
+
+  // Just return received message if any received message is queued.
+  if (!received_messages_.empty()) {
+    receive_callback_var_ = message;
+    return DoReceive();
+  }
+
+  // Check state again. In CLOSED state, no more messages will be received.
+  if (state_ == PP_WEBSOCKETREADYSTATE_CLOSED)
+    return PP_ERROR_BADARGUMENT;
+
+  // Returns PP_ERROR_FAILED after an error is received and received messages
+  // is exhausted.
+  if (error_was_received_)
+    return PP_ERROR_FAILED;
+
+  // Or retain |message| as buffer to store and install |callback|.
+  receive_callback_var_ = message;
+  receive_callback_ = callback;
+
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t WebSocketResource::SendMessage(const PP_Var& message) {
+  // Check state.
+  if (state_ == PP_WEBSOCKETREADYSTATE_INVALID ||
+      state_ == PP_WEBSOCKETREADYSTATE_CONNECTING)
+    return PP_ERROR_BADARGUMENT;
+
+  if (state_ == PP_WEBSOCKETREADYSTATE_CLOSING ||
+      state_ == PP_WEBSOCKETREADYSTATE_CLOSED) {
+    // Handle buffered_amount_after_close_.
+    uint64_t payload_size = 0;
+    if (message.type == PP_VARTYPE_STRING) {
+      scoped_refptr<StringVar> message_string = StringVar::FromPPVar(message);
+      if (message_string)
+        payload_size += message_string->value().length();
+    } else if (message.type == PP_VARTYPE_ARRAY_BUFFER) {
+      scoped_refptr<ArrayBufferVar> message_array_buffer =
+          ArrayBufferVar::FromPPVar(message);
+      if (message_array_buffer)
+        payload_size += message_array_buffer->ByteLength();
+    } else {
+      // TODO(toyoshim): Support Blob.
+      return PP_ERROR_NOTSUPPORTED;
+    }
+
+    buffered_amount_after_close_ =
+        SaturateAdd(buffered_amount_after_close_, GetFrameSize(payload_size));
+
+    return PP_ERROR_FAILED;
+  }
+
+  // Send the message.
+  if (message.type == PP_VARTYPE_STRING) {
+    // Convert message to std::string, then send it.
+    scoped_refptr<StringVar> message_string = StringVar::FromPPVar(message);
+    if (!message_string)
+      return PP_ERROR_BADARGUMENT;
+    CallRenderer(PpapiHostMsg_WebSocket_SendText(message_string->value()));
+  } else if (message.type == PP_VARTYPE_ARRAY_BUFFER) {
+    // Convert message to std::vector<uint8_t>, then send it.
+    scoped_refptr<ArrayBufferVar> message_arraybuffer =
+        ArrayBufferVar::FromPPVar(message);
+    if (!message_arraybuffer)
+      return PP_ERROR_BADARGUMENT;
+    uint8_t* message_data = static_cast<uint8_t*>(message_arraybuffer->Map());
+    uint32 message_length = message_arraybuffer->ByteLength();
+    std::vector<uint8_t> message_vector(message_data,
+                                        message_data + message_length);
+    CallRenderer(PpapiHostMsg_WebSocket_SendBinary(message_vector));

[brettw, 2012/10/03 20:30:24]

For the cases where you don't need a callback, you should use 
PostToRenderer instead. This will avoid sending the reply. Otherwise, the
PpapiHost code will implicitly generate a reply containing PP_OK on the host
side, which will be unnecessary.

So can you go through all the places where you do "Call" for messages without
replies and replace them with "Post"?

[Takashi Toyoshima, 2012/10/05 07:35:01]

Thank you.
I misunderstood about params.has_callback() check in
PpapiHost::HandleResourceCall() because I didn't know PostToRenderer. This
misunderstanding is the reason why I implemented SendReply() in
pepper_websocket_host.cc implicitly.

Yes, I use PostToRenderer here.

+  } else {
+    // TODO(toyoshim): Support Blob.
+    return PP_ERROR_NOTSUPPORTED;
+  }
+  return PP_OK;
+}
+
+uint64_t WebSocketResource::GetBufferedAmount() {
+  return SaturateAdd(buffered_amount_, buffered_amount_after_close_);
+}
+
+uint16_t WebSocketResource::GetCloseCode() {
+  return close_code_;
+}
+
+PP_Var WebSocketResource::GetCloseReason() {
+  if (!close_reason_)
+    return empty_string_->GetPPVar();
+  return close_reason_->GetPPVar();
+}
+
+PP_Bool WebSocketResource::GetCloseWasClean() {
+  return close_was_clean_;
+}
+
+PP_Var WebSocketResource::GetExtensions() {
+  return StringVar::StringToPPVar(std::string());
+}
+
+PP_Var WebSocketResource::GetProtocol() {
+  if (!protocol_)
+    return empty_string_->GetPPVar();
+  return protocol_->GetPPVar();
+}
+
+PP_WebSocketReadyState WebSocketResource::GetReadyState() {
+  return state_;
+}
+
+PP_Var WebSocketResource::GetURL() {
+  if (!url_)
+    return empty_string_->GetPPVar();
+  return url_->GetPPVar();
+}
+
+void WebSocketResource::OnReplyReceived(
+    const ResourceMessageReplyParams& params,
+    const IPC::Message& msg) {
+  // TODO(toyoshim): DISPATCH_RESOURCE_REPLY will be replaced with other
+  // mechanisms. WebSocket dispatches IPC messages manually for now and must be
+  // replaced with the new one in the future.
+  switch (msg.type()) {
+    case PpapiPluginMsg_WebSocket_ConnectReply::ID: {
+      PpapiPluginMsg_WebSocket_ConnectReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_ConnectReply::Read(&msg, &p))
+        OnPluginMsgConnectReply(params, p.a, p.b);
+      else  // On error use default params and run the callback.
+        OnPluginMsgConnectReply(params, std::string(), std::string());
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_CloseReply::ID: {
+      PpapiPluginMsg_WebSocket_CloseReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_CloseReply::Read(&msg, &p))
+        OnPluginMsgCloseReply(params, p.a, p.b, p.c, p.d);
+      else  // On error use default params and run the callback.
+        OnPluginMsgCloseReply(params, 0, false, 0, std::string());
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_ReceiveTextReply::ID: {
+      PpapiPluginMsg_WebSocket_ReceiveTextReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_ReceiveTextReply::Read(&msg, &p))
+        OnPluginMsgReceiveTextReply(params, p.a);
+      else
+        NOTREACHED();
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_ReceiveBinaryReply::ID: {
+      PpapiPluginMsg_WebSocket_ReceiveBinaryReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_ReceiveBinaryReply::Read(&msg, &p))
+        OnPluginMsgReceiveBinaryReply(params, p.a);
+      else
+        NOTREACHED();
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_ErrorReply::ID: {
+      OnPluginMsgErrorReply(params);
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_BufferedAmountReply::ID: {
+      PpapiPluginMsg_WebSocket_BufferedAmountReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_BufferedAmountReply::Read(&msg, &p))
+        OnPluginMsgBufferedAmountReply(params, p.a);
+      else
+        NOTREACHED();
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_StateReply::ID: {
+      PpapiPluginMsg_WebSocket_StateReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_StateReply::Read(&msg, &p))
+        OnPluginMsgStateReply(params, p.a);
+      else
+        NOTREACHED();
+      break;
+    }
+    case PpapiPluginMsg_WebSocket_ClosedReply::ID: {
+      PpapiPluginMsg_WebSocket_ClosedReply::Schema::Param p;
+      if (PpapiPluginMsg_WebSocket_ClosedReply::Read(&msg, &p))
+        OnPluginMsgClosedReply(params, p.a, p.b, p.c, p.d);
+      else
+        NOTREACHED();
+      break;
+    }
+    default:
+      NOTREACHED();
+  }
+}
+
+void WebSocketResource::OnPluginMsgConnectReply(
+    const ResourceMessageReplyParams& params,
+    const std::string& url,
+    const std::string& protocol) {
+  if (!TrackedCallback::IsPending(connect_callback_))
+    return;
+
+  int32_t result = params.result();
+  if (result == PP_OK) {
+    state_ = PP_WEBSOCKETREADYSTATE_OPEN;
+    protocol_ = new StringVar(protocol);
+  } else {
+    url_ = new StringVar(url);
+  }
+  if (result != PP_OK_COMPLETIONPENDING)
+    TrackedCallback::ClearAndRun(&connect_callback_, params.result());
+}
+
+void WebSocketResource::OnPluginMsgCloseReply(
+    const ResourceMessageReplyParams& params,
+    unsigned long buffered_amount,
+    bool was_clean,
+    unsigned short code,
+    const std::string& reason) {
+  // Set close related properties.
+  state_ = PP_WEBSOCKETREADYSTATE_CLOSED;
+  buffered_amount_ = buffered_amount;
+  close_was_clean_ = PP_FromBool(was_clean);
+  close_code_ = code;
+  close_reason_ = new StringVar(reason);
+
+  if (TrackedCallback::IsPending(connect_callback_)) {
+    connect_callback_->PostRun(PP_ERROR_FAILED);
+  }
+
+  if (TrackedCallback::IsPending(receive_callback_)) {
+    receive_callback_var_ = NULL;
+    receive_callback_->PostRun(PP_ERROR_FAILED);
+  }
+
+  if (!TrackedCallback::IsPending(close_callback_))
+    return;
+
+  close_callback_->PostRun(params.result());
+}
+
+void WebSocketResource::OnPluginMsgReceiveTextReply(
+    const ResourceMessageReplyParams& params,
+    const std::string& message) {
+  // Dispose packets after receiving an error or in invalid state.
+  if (error_was_received_ || !InValidStateToReceive(state_))
+     return;
+
+  // Append received data to queue.
+  received_messages_.push(scoped_refptr<Var>(new StringVar(message)));
+
+  if (!TrackedCallback::IsPending(receive_callback_))
+    return;
+
+  TrackedCallback::ClearAndRun(&receive_callback_, DoReceive());
+}
+
+void WebSocketResource::OnPluginMsgReceiveBinaryReply(
+    const ResourceMessageReplyParams& params,
+    const std::vector<uint8_t>& message) {
+  // Dispose packets after receiving an error or in invalid state.
+  if (error_was_received_ || !InValidStateToReceive(state_))
+     return;

[brettw, 2012/10/03 20:30:24]

Indenting is one space too much. This is also the case in the previous function
and maybe others (I assume this check was copy and pasted).

[Takashi Toyoshima, 2012/10/05 07:35:01]

Oops.
Thank you for catching these nits.

+
+  // Append received data to queue.
+  scoped_refptr<Var> message_var(ArrayBufferVar::FromPPVar(
+      PpapiGlobals::Get()->GetVarTracker()->MakeArrayBufferPPVar(
+          message.size(),
+          &message.front())));
+  received_messages_.push(message_var);
+
+  if (!TrackedCallback::IsPending(receive_callback_))
+    return;
+
+  TrackedCallback::ClearAndRun(&receive_callback_, DoReceive());
+}
+
+void WebSocketResource::OnPluginMsgErrorReply(
+    const ResourceMessageReplyParams& params) {
+}
+
+void WebSocketResource::OnPluginMsgBufferedAmountReply(
+    const ResourceMessageReplyParams& params,
+    unsigned long buffered_amount) {
+  buffered_amount_ = buffered_amount;
+}
+
+void WebSocketResource::OnPluginMsgStateReply(
+    const ResourceMessageReplyParams& params,
+    int32_t state) {
+  state_ = static_cast<PP_WebSocketReadyState>(state);
+}
+
+void WebSocketResource::OnPluginMsgClosedReply(
+    const ResourceMessageReplyParams& params,
+    unsigned long buffered_amount,
+    bool was_clean,
+    unsigned short code,
+    const std::string& reason) {
+  OnPluginMsgCloseReply(params, buffered_amount, was_clean, code, reason);
+}
+
+int32_t WebSocketResource::DoReceive() {
+  if (!receive_callback_var_)
+    return PP_OK;
+
+  *receive_callback_var_ = received_messages_.front()->GetPPVar();
+  received_messages_.pop();
+  receive_callback_var_ = NULL;
+  return PP_OK;
+}
+
+}  // namespace proxy
+}  // namespace ppapi