Add Socket::ReadIfReady()

net/socket/socket_bio_adapter.cc

Index: net/socket/socket_bio_adapter.cc
diff --git a/net/socket/socket_bio_adapter.cc b/net/socket/socket_bio_adapter.cc
index 0d75e68ec85890a2def5983dfdb1a4332a8d81e3..1d111e51a357674ce5fe2ab52ae28869c720ffed 100644
--- a/net/socket/socket_bio_adapter.cc
+++ b/net/socket/socket_bio_adapter.cc
@@ -11,9 +11,11 @@
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
+#include "base/metrics/field_trial.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
+#include "net/socket/socket.h"
 #include "net/socket/stream_socket.h"
 #include "net/ssl/openssl_ssl_util.h"
 #include "third_party/boringssl/src/include/openssl/bio.h"
@@ -87,8 +89,20 @@ int SocketBIOAdapter::BIORead(char* out, int len) {
     DCHECK(!read_buffer_);
     DCHECK_EQ(0, read_offset_);
     read_buffer_ = new IOBuffer(read_buffer_capacity_);
-    int result = socket_->Read(read_buffer_.get(), read_buffer_capacity_,
-                               read_callback_);
+    int result = ERR_READ_IF_READY_NOT_IMPLEMENTED;
+    if (base::FieldTrialList::FindFullName(Socket::kReadIfReadyTrialName) ==
+        "enable") {
+      result = socket_->ReadIfReady(
+          read_buffer_.get(), read_buffer_capacity_,
+          base::Bind(&SocketBIOAdapter::OnSocketReadIfReadyComplete,
+                     weak_factory_.GetWeakPtr()));
+      if (result == ERR_IO_PENDING)
+        read_buffer_ = nullptr;
+    }
+    if (result == ERR_READ_IF_READY_NOT_IMPLEMENTED) {
+      result = socket_->Read(read_buffer_.get(), read_buffer_capacity_,
+                             read_callback_);
+    }
     if (result == ERR_IO_PENDING) {
       read_result_ = ERR_IO_PENDING;
     } else {
@@ -143,7 +157,17 @@ void SocketBIOAdapter::OnSocketReadComplete(int result) {
   DCHECK_EQ(ERR_IO_PENDING, read_result_);
 
   HandleSocketReadResult(result);
-  delegate_->OnReadReady();
+  delegate_->OnReadReady(read_result_ > 0 ? OK : read_result_);
+}
+
+void SocketBIOAdapter::OnSocketReadIfReadyComplete(int result) {
+  DCHECK_EQ(ERR_IO_PENDING, read_result_);
+  DCHECK_GE(OK, result);
+
+  // Do not use HandleSocketReadResult() because |result == OK| doesn't mean EOF
+  read_result_ = result;
+
+  delegate_->OnReadReady(read_result_);
 }
 
 int SocketBIOAdapter::BIOWrite(const char* in, int len) {
@@ -214,7 +238,7 @@ int SocketBIOAdapter::BIOWrite(const char* in, int len) {
       read_result_ == ERR_IO_PENDING) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&SocketBIOAdapter::CallOnReadReady,
-                              weak_factory_.GetWeakPtr()));
+                              weak_factory_.GetWeakPtr(), write_error_));
   }
 
   return bytes_copied;
@@ -271,7 +295,8 @@ void SocketBIOAdapter::OnSocketWriteComplete(int result) {
   // OnWriteReady.
   if (was_full) {
     base::WeakPtr<SocketBIOAdapter> guard(weak_factory_.GetWeakPtr());
-    delegate_->OnWriteReady();
+    DCHECK_GE(OK, write_error_);
+    delegate_->OnWriteReady(write_error_);
     // OnWriteReady may delete the adapter.
     if (!guard)
       return;
@@ -280,12 +305,12 @@ void SocketBIOAdapter::OnSocketWriteComplete(int result) {
   // Write errors are fed back into BIO_read once the read buffer is empty. If
   // BIO_read is currently blocked, signal early that a read result is ready.
   if (result < 0 && read_result_ == ERR_IO_PENDING)
-    delegate_->OnReadReady();
+    delegate_->OnReadReady(result);
 }
 
-void SocketBIOAdapter::CallOnReadReady() {
+void SocketBIOAdapter::CallOnReadReady(int rv) {
   if (read_result_ == ERR_IO_PENDING)
-    delegate_->OnReadReady();
+    delegate_->OnReadReady(rv);
 }
 
 SocketBIOAdapter* SocketBIOAdapter::GetAdapter(BIO* bio) {