[NaCl SDK] nacl_io: Add support for non-blocking connect/accept

native_client_sdk/src/libraries/nacl_io/mount_node_tcp.cc

 // Copyright (c) 2013 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 "nacl_io/ossocket.h"
 #ifdef PROVIDES_SOCKET_API
 
+#include <assert.h>
 #include <errno.h>
 #include <string.h>
 #include <algorithm>
 
+#include "nacl_io/kernel_handle.h"
 #include "nacl_io/mount_node_tcp.h"
 #include "nacl_io/mount_stream.h"
 #include "nacl_io/pepper_interface.h"
 
 namespace {
   const size_t kMaxPacketSize = 65536;
   const size_t kDefaultFifoSize = kMaxPacketSize * 8;
 }
 
 namespace nacl_io {
@@ skipping 27 matching lines @@
   virtual bool Start(int32_t val) {
     AUTO_LOCK(emitter_->GetLock());
     MountNodeTCP* stream = static_cast<MountNodeTCP*>(emitter_->stream());
 
     // Does the stream exist, and can it send?
     if (NULL == stream || !stream->TestStreamFlags(SSF_CAN_SEND))
       return false;
 
     // If not currently sending...
     if (!stream->TestStreamFlags(SSF_SENDING)) {
-      size_t tx_data_avail = emitter_->out_fifo()->ReadAvailable();
+      size_t tx_data_avail = emitter_->BytesInOutputFIFO();
       int capped_len = std::min(tx_data_avail, kMaxPacketSize);
 
       if (capped_len == 0)
         return false;
 
       data_ = new char[capped_len];
       emitter_->ReadOut_Locked(data_, capped_len);
 
       stream->SetStreamFlags(SSF_SENDING);
       int err = TCPInterface()->Write(stream->socket_resource(),
@@ skipping 35 matching lines @@
   virtual bool Start(int32_t val) {
     AUTO_LOCK(emitter_->GetLock());
     MountNodeTCP* stream = static_cast<MountNodeTCP*>(emitter_->stream());
 
     // Does the stream exist, and can it recv?
     if (NULL == stream || !stream->TestStreamFlags(SSF_CAN_RECV))
       return false;
 
     // If we are not currently receiving
     if (!stream->TestStreamFlags(SSF_RECVING)) {
-      size_t rx_space_avail = emitter_->in_fifo()->WriteAvailable();
+      size_t rx_space_avail = emitter_->SpaceInInputFIFO();
       int capped_len =
           static_cast<int32_t>(std::min(rx_space_avail, kMaxPacketSize));
 
       if (capped_len == 0)
         return false;
 
       stream->SetStreamFlags(SSF_RECVING);
       data_ = new char[capped_len];
       int err = TCPInterface()->Read(stream->socket_resource(),
                                      data_,
@@ skipping 18 matching lines @@
         emitter_->WriteIn_Locked(data_, length_error);
         stream->ClearStreamFlags(SSF_RECVING);
         stream->QueueInput();
       } else {
         stream->SetError_Locked(length_error);
       }
     }
   }
 };
 
+class TCPAcceptWork : public MountStream::Work {
+ public:
+  explicit TCPAcceptWork(MountStream* stream,
+                         const ScopedEventEmitterTCP& emitter)
+      : MountStream::Work(stream),
+        emitter_(emitter) {}
+
+  TCPSocketInterface* TCPInterface() {
+    return mount()->ppapi()->GetTCPSocketInterface();
+  }
+
+  virtual bool Start(int32_t val) {
+    AUTO_LOCK(emitter_->GetLock());
+    MountNodeTCP* node = static_cast<MountNodeTCP*>(emitter_->stream());
+
+    // Does the stream exist, and can it accept?
+    if (NULL == node)
+      return false;
+
+    // If we are not currently accepting
+    if (!node->TestStreamFlags(SSF_LISTENING))
+      return false;
+
+    int err = TCPInterface()->Accept(node->socket_resource(),
+                                     &new_socket_,
+                                     mount()->GetRunCompletion(this));
+
+    if (err != PP_OK_COMPLETIONPENDING)
+      // Anything else, we should assume the socket has gone bad.
+      node->SetError_Locked(err);
+
+    return true;
+  }
+
+  virtual void Run(int32_t error) {
+    AUTO_LOCK(emitter_->GetLock());
+    MountNodeTCP* node = static_cast<MountNodeTCP*>(emitter_->stream());
+
+    if (node == NULL)
+      return;
+
+    if (error != PP_OK) {
+      node->SetError_Locked(error);
+      return;
+    }
+
+    emitter_->SetAcceptedSocket_Locked(new_socket_);
+  }
+
+ protected:
+  PP_Resource new_socket_;
+  ScopedEventEmitterTCP emitter_;
+};
+
+class TCPConnectWork : public MountStream::Work {
+ public:
+  explicit TCPConnectWork(MountStream* stream,
+                          const ScopedEventEmitterTCP& emitter)
+      : MountStream::Work(stream),
+        emitter_(emitter) {}
+
+  TCPSocketInterface* TCPInterface() {
+    return mount()->ppapi()->GetTCPSocketInterface();
+  }
+
+  virtual bool Start(int32_t val) {
+    AUTO_LOCK(emitter_->GetLock());
+    MountNodeTCP* node = static_cast<MountNodeTCP*>(emitter_->stream());
+
+    // Does the stream exist, and can it connect?
+    if (NULL == node)
+      return false;
+
+    int err = TCPInterface()->Connect(node->socket_resource(),
+                                      node->remote_addr(),
+                                      mount()->GetRunCompletion(this));
+
+    if (err != PP_OK_COMPLETIONPENDING)
+      // Anything else, we should assume the socket has gone bad.
+      node->SetError_Locked(err);
+
+    return true;
+  }
+
+  virtual void Run(int32_t error) {
+    AUTO_LOCK(emitter_->GetLock());
+    MountNodeTCP* node = static_cast<MountNodeTCP*>(emitter_->stream());
+
+    if (node == NULL)
+      return;
+
+    if (error != PP_OK) {
+      node->ConnectFailed_Locked();
+      node->SetError_Locked(error);
+      return;
+    }
+
+    node->ConnectDone_Locked();
+  }
+
+ protected:
+  ScopedEventEmitterTCP emitter_;
+};
+
 MountNodeTCP::MountNodeTCP(Mount* mount)
     : MountNodeSocket(mount),
       emitter_(new EventEmitterTCP(kDefaultFifoSize, kDefaultFifoSize)) {
   emitter_->AttachStream(this);
 }
 
 MountNodeTCP::MountNodeTCP(Mount* mount, PP_Resource socket)
     : MountNodeSocket(mount, socket),
       emitter_(new EventEmitterTCP(kDefaultFifoSize, kDefaultFifoSize)) {
   emitter_->AttachStream(this);
 }
 
 void MountNodeTCP::Destroy() {
   emitter_->DetachStream();
   MountNodeSocket::Destroy();
 }
 
 Error MountNodeTCP::Init(int open_flags) {
   Error err = MountNodeSocket::Init(open_flags);
   if (err != 0)
     return err;
 
   if (TCPInterface() == NULL)
     return EACCES;
 
+  SetStreamFlags(SSF_CAN_CONNECT);
+
   if (socket_resource_ != 0) {
     // TCP sockets that are contructed with an existing socket_resource_
     // are those that generated from calls to Accept() and therefore are
     // already connected.
     remote_addr_ = TCPInterface()->GetRemoteAddress(socket_resource_);
-    ConnectDone();
+    ConnectDone_Locked();
   } else {
     socket_resource_ = TCPInterface()->Create(mount_->ppapi()->GetInstance());
     if (0 == socket_resource_)
       return EACCES;
   }
 
   return 0;
 }
 
-EventEmitterTCP* MountNodeTCP::GetEventEmitter() {
+EventEmitter* MountNodeTCP::GetEventEmitter() {
   return emitter_.get();
 }
 
+void MountNodeTCP::QueueAccept() {
+  MountStream::Work* work = new TCPAcceptWork(mount_stream(), emitter_);
+  mount_stream()->EnqueueWork(work);
+}
+
+void MountNodeTCP::QueueConnect() {
+  MountStream::Work* work = new TCPConnectWork(mount_stream(), emitter_);
+  mount_stream()->EnqueueWork(work);
+}
+
 void MountNodeTCP::QueueInput() {
-  TCPRecvWork* work = new TCPRecvWork(emitter_);
+  MountStream::Work* work = new TCPRecvWork(emitter_);
   mount_stream()->EnqueueWork(work);
 }
 
 void MountNodeTCP::QueueOutput() {
-  TCPSendWork* work = new TCPSendWork(emitter_);
+  MountStream::Work* work = new TCPSendWork(emitter_);
   mount_stream()->EnqueueWork(work);
 }
 
-Error MountNodeTCP::Accept(PP_Resource* out_sock,
+Error MountNodeTCP::Accept(const HandleAttr& attr,
+                           PP_Resource* out_sock,
                            struct sockaddr* addr,
                            socklen_t* len) {
-  AUTO_LOCK(node_lock_);
-  int err = TCPInterface()->Accept(socket_resource_,
-                                   out_sock,
-                                   PP_BlockUntilComplete());
+  EventListenerLock wait(GetEventEmitter());
 
-  if (err != PP_OK)
-    return PPErrorToErrno(err);
+  if (!TestStreamFlags(SSF_LISTENING))
+    return EINVAL;
 
+  // Either block forever or not at all
+  int ms = attr.IsBlocking() ? -1 : 0;
+
+  Error err = wait.WaitOnEvent(POLLIN, ms);
+
+  if (ETIMEDOUT == err)
+    return EWOULDBLOCK;
+
+  int s = emitter_->GetAcceptedSocket_Locked();
+  // Non-blocking case.
+  if (s == 0)
+    return EAGAIN;
+
+  // Consume the new socket and start listening for the next one
+  *out_sock = s;
+  emitter_->ClearEvents_Locked(POLLIN);
+
+  // Set the out paramaters
   PP_Resource remote_addr = TCPInterface()->GetRemoteAddress(*out_sock);
   *len = ResourceToSockAddr(remote_addr, *len, addr);
   mount_->ppapi()->ReleaseResource(remote_addr);
+
+  QueueAccept();
   return 0;
 }
 
 // We can not bind a client socket with PPAPI.  For now we ignore the
 // bind but report the correct address later, just in case someone is
 // binding without really caring what the address is (for example to
 // select a more optimized interface/route.)
 Error MountNodeTCP::Bind(const struct sockaddr* addr, socklen_t len) {
   AUTO_LOCK(node_lock_);
 
   /* Only bind once. */
   if (local_addr_ != 0)
     return EINVAL;
 
   local_addr_ = SockAddrToResource(addr, len);
   int err = TCPInterface()->Bind(socket_resource_,
                                  local_addr_,
                                  PP_BlockUntilComplete());
 
   // If we fail, release the local addr resource
   if (err != PP_OK) {
     mount_->ppapi()->ReleaseResource(local_addr_);
     local_addr_ = 0;
     return PPErrorToErrno(err);
   }
 
   return 0;
 }
 
-Error MountNodeTCP::Connect(const struct sockaddr* addr, socklen_t len) {
-  AUTO_LOCK(node_lock_);
+Error MountNodeTCP::Connect(const HandleAttr& attr,
+                            const struct sockaddr* addr,
+                            socklen_t len) {
+  EventListenerLock wait(GetEventEmitter());
 
-  if (remote_addr_ != 0)
+  if (TestStreamFlags(SSF_CONNECTING))
+    return EALREADY;
+
+  if (remote_addr_ != 0) {
     return EISCONN;
+  }
 
   remote_addr_ = SockAddrToResource(addr, len);
   if (0 == remote_addr_)
     return EINVAL;
 
-  int err = TCPInterface()->Connect(socket_resource_,
-                                    remote_addr_,
-                                    PP_BlockUntilComplete());
+  int ms = attr.IsBlocking() ? -1 : 0;
+
+  SetStreamFlags(SSF_CONNECTING);
+  QueueConnect();
+
+  Error err = wait.WaitOnEvent(POLLOUT, ms);
+  if (ETIMEDOUT == err)
+    return EINPROGRESS;
 
   // If we fail, release the dest addr resource
-  if (err != PP_OK) {
-    mount_->ppapi()->ReleaseResource(remote_addr_);
-    remote_addr_ = 0;
-    return PPErrorToErrno(err);
+  if (err != 0) {
+    ConnectFailed_Locked();
+    return err;
   }
 
-  ConnectDone();
+  ConnectDone_Locked();
   return 0;
 }
 
-void MountNodeTCP::ConnectDone() {
+void MountNodeTCP::ConnectDone_Locked() {
   local_addr_ = TCPInterface()->GetLocalAddress(socket_resource_);
 
   // Now that we are connected, we can start sending and receiving.
+  ClearStreamFlags(SSF_CONNECTING | SSF_CAN_CONNECT);
   SetStreamFlags(SSF_CAN_SEND | SSF_CAN_RECV);
 
+  emitter_->ConnectDone_Locked();
+
   // Begin the input pump
   QueueInput();
 }
 
+void MountNodeTCP::ConnectFailed_Locked() {
+  mount_->ppapi()->ReleaseResource(remote_addr_);
+  remote_addr_ = 0;
+}
+
 Error MountNodeTCP::Listen(int backlog) {
+  AUTO_LOCK(node_lock_);
+  if (0 == local_addr_)
+    return EINVAL;
+
   int err = TCPInterface()->Listen(socket_resource_,
                                    backlog,
                                    PP_BlockUntilComplete());
   if (err != PP_OK)
     return PPErrorToErrno(err);
 
+  ClearStreamFlags(SSF_CAN_CONNECT);
+  SetStreamFlags(SSF_LISTENING);
+  QueueAccept();
   return 0;
 }
 
 Error MountNodeTCP::Recv_Locked(void* buf,
                                 size_t len,
                                 PP_Resource* out_addr,
                                 int* out_len) {
+  assert(emitter_.get());
   *out_len = emitter_->ReadIn_Locked((char*)buf, len);
   *out_addr = remote_addr_;
 
   // Ref the address copy we pass back.
   mount_->ppapi()->AddRefResource(remote_addr_);
   return 0;
 }
 
 // TCP ignores dst addr passed to send_to, and always uses bound address
 Error MountNodeTCP::Send_Locked(const void* buf,
                                 size_t len,
                                 PP_Resource,
                                 int* out_len) {
+  assert(emitter_.get());
   *out_len = emitter_->WriteOut_Locked((char*)buf, len);
   return 0;
 }
 
 
 }  // namespace nacl_io
 
 #endif  // PROVIDES_SOCKET_API