Implment BytesConsumer::tee

third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp

Index: third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp b/third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp
index f77611c5b857f3d687c58aac029616abc321e42f..b5e4fa105ff52f49f99196d5d7b33c6f2c177c6a 100644
--- a/third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp
+++ b/third_party/WebKit/Source/modules/fetch/BytesConsumerForDataConsumerHandle.cpp
@@ -18,6 +18,7 @@ BytesConsumerForDataConsumerHandle::~BytesConsumerForDataConsumerHandle() {}
 
 BytesConsumer::Result BytesConsumerForDataConsumerHandle::read(char* buffer, size_t size, size_t* readSize)
 {
+    DCHECK(!m_isInTwoPhaseRead);
     *readSize = 0;
     if (m_state == InternalState::Closed)
         return Result::Done;
@@ -45,6 +46,7 @@ BytesConsumer::Result BytesConsumerForDataConsumerHandle::read(char* buffer, siz
 
 BytesConsumer::Result BytesConsumerForDataConsumerHandle::beginRead(const char** buffer, size_t* available)
 {
+    DCHECK(!m_isInTwoPhaseRead);
     *buffer = nullptr;
     *available = 0;
     if (m_state == InternalState::Closed)
@@ -55,6 +57,7 @@ BytesConsumer::Result BytesConsumerForDataConsumerHandle::beginRead(const char**
     WebDataConsumerHandle::Result r = m_reader->beginRead(reinterpret_cast<const void**>(buffer), WebDataConsumerHandle::FlagNone, available);
     switch (r) {
     case WebDataConsumerHandle::Ok:
+        m_isInTwoPhaseRead = true;
         return Result::Ok;
     case WebDataConsumerHandle::ShouldWait:
         return Result::ShouldWait;
@@ -73,12 +76,16 @@ BytesConsumer::Result BytesConsumerForDataConsumerHandle::beginRead(const char**
 
 BytesConsumer::Result BytesConsumerForDataConsumerHandle::endRead(size_t read)
 {
+    DCHECK(m_isInTwoPhaseRead);
+    m_isInTwoPhaseRead = false;
     DCHECK(m_state == InternalState::Readable || m_state == InternalState::Waiting);
     WebDataConsumerHandle::Result r = m_reader->endRead(read);
-    if (r == WebDataConsumerHandle::Ok)
-        return Result::Ok;
-    error();
-    return Result::Error;
+    if (m_hasPendingError || r != WebDataConsumerHandle::Ok) {
+        m_hasPendingError = false;
+        error();
+        return Result::Error;
+    }
+    return Result::Ok;
 }
 
 PassRefPtr<BlobDataHandle> BytesConsumerForDataConsumerHandle::drainAsBlobDataHandle(BlobSizePolicy policy)
@@ -113,17 +120,18 @@ void BytesConsumerForDataConsumerHandle::setClient(BytesConsumer::Client* client
 {
     DCHECK(!m_client);
     DCHECK(client);
-    m_client = client;
+    if (m_state == InternalState::Readable || m_state == InternalState::Waiting)
+        m_client = client;
 }
 
 void BytesConsumerForDataConsumerHandle::clearClient()
 {
-    DCHECK(m_client);
     m_client = nullptr;
 }
 
 void BytesConsumerForDataConsumerHandle::cancel()
 {
+    DCHECK(!m_isInTwoPhaseRead);
     if (m_state == InternalState::Readable || m_state == InternalState::Waiting) {
         // We don't want the client to be notified in this case.
         BytesConsumer::Client* client = m_client;
@@ -144,23 +152,28 @@ void BytesConsumerForDataConsumerHandle::didGetReadable()
     // Perform zero-length read to call check handle's status.
     size_t readSize;
     WebDataConsumerHandle::Result result = m_reader->read(nullptr, 0, WebDataConsumerHandle::FlagNone, &readSize);
+    BytesConsumer::Client* client = m_client;
     switch (result) {
     case WebDataConsumerHandle::Ok:
     case WebDataConsumerHandle::ShouldWait:
-        if (m_client)
-            m_client->onStateChange();
+        if (client)
+            client->onStateChange();
         return;
     case WebDataConsumerHandle::Done:
         close();
-        if (m_client)
-            m_client->onStateChange();
+        if (client)
+            client->onStateChange();
         return;
     case WebDataConsumerHandle::Busy:
     case WebDataConsumerHandle::ResourceExhausted:
     case WebDataConsumerHandle::UnexpectedError:
-        error();
-        if (m_client)
-            m_client->onStateChange();
+        if (m_isInTwoPhaseRead) {

[hiroshige, 2016/09/07 09:17:47]

Should we do this check before m_reader->read()? we can't call read() during
two-phase read.

[yhirano, 2016/09/07 10:51:34]

Done.

+            m_hasPendingError = true;
+        } else {
+            error();
+            if (client)
+                client->onStateChange();
+        }
         return;
     }
     return;
@@ -174,21 +187,25 @@ DEFINE_TRACE(BytesConsumerForDataConsumerHandle)
 
 void BytesConsumerForDataConsumerHandle::close()
 {
+    DCHECK(!m_isInTwoPhaseRead);
     if (m_state == InternalState::Closed)
         return;
     DCHECK(m_state == InternalState::Readable || m_state == InternalState::Waiting);
     m_state = InternalState::Closed;
     m_reader = nullptr;
+    clearClient();
 }
 
 void BytesConsumerForDataConsumerHandle::error()
 {
+    DCHECK(!m_isInTwoPhaseRead);
     if (m_state == InternalState::Errored)
         return;
     DCHECK(m_state == InternalState::Readable || m_state == InternalState::Waiting);
     m_state = InternalState::Errored;
     m_reader = nullptr;
     m_error = Error("error");
+    clearClient();
 }
 
 } // namespace blink