Persists the virtual buffer size when switching to app owned buffers

docs/Streams.md

@@ -167,6 +167,7 @@ There is no guarantee the `QUIC_BUFFER`s indicated in a receive notification wil
 
 The application is responsible for tracking the amount of data received and when a buffer it provided has been fully used.
 The application regains full ownership of a buffer after it get a receive notification for all bytes in the buffer and accept them by calling [StreamReceiveComplete](api/StreamReceiveComplete.md).
+MsQuic will not re-use a buffer for subsequent receives once it has been fully written, unless the app submits the same buffer again.
 If the application accepts all the buffer's bytes **inline** from the receive notification, by returning `QUIC_STATUS_SUCCESS` and setting `TotalBufferLength` appropriately,
 it can free or reuse the buffer while in the notification handler.
 

src/core/stream.c

@@ -977,6 +977,15 @@ QuicStreamSwitchToAppOwnedBuffers(
     _In_ QUIC_STREAM* Stream
     )
 {
+    //
+    // Preserve the initial receive window size: it should not have changed
+    // since the stream's creation.
+    //
+    const uint32_t InitialControlFlow = Stream->RecvBuffer.VirtualBufferLength;
+    CXPLAT_DBG_ASSERT(
+        InitialControlFlow == Stream->Connection->Settings.StreamRecvWindowBidiRemoteDefault ||
+        InitialControlFlow == Stream->Connection->Settings.StreamRecvWindowUnidiDefault);
+
     //
     // Reset the current receive buffer
     //
@@ -988,7 +997,7 @@ QuicStreamSwitchToAppOwnedBuffers(
     (void)QuicRecvBufferInitialize(
         &Stream->RecvBuffer,
         0,
-        0,
+        InitialControlFlow,
         QUIC_RECV_BUF_MODE_APP_OWNED,
         NULL);
     Stream->Flags.UseAppOwnedRecvBuffers = TRUE;

src/test/MsQuicTests.h

@@ -642,10 +642,41 @@ QuicTestEcn(
     const FamilyArgs& Params
     );
 
-void QuicTestStreamAppProvidedBuffers(
+struct AppProvidedBuffersConfig {
+    uint32_t StreamStartBuffersNum;
+    uint32_t StreamStartBuffersSize;
+    uint32_t AdditionalBuffersNum;
+    uint32_t AdditionalBuffersSize;
+};
+
+void
+QuicTestStreamAppProvidedBuffers_ClientSend(
+    const AppProvidedBuffersConfig& BufferConfig
+    );
+
+void
+QuicTestStreamAppProvidedBuffers_ServerSend(
+    const AppProvidedBuffersConfig& BufferConfig
+    );
+
+void
+QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream(
+    const AppProvidedBuffersConfig& BufferConfig
+    );
+
+void
+QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer(
+    const AppProvidedBuffersConfig& BufferConfig
     );
 
-void QuicTestStreamAppProvidedBuffersOutOfSpace(
+void
+QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream(
+    const AppProvidedBuffersConfig& BufferConfig
+    );
+
+void
+QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer(
+    const AppProvidedBuffersConfig& BufferConfig
     );
 
 //

src/test/bin/quic_gtest.cpp

@@ -10,6 +10,8 @@
 #include "quic_gtest.cpp.clog.h"
 #endif
 
+#include <MsQuicTests.h>
+
 #include <array>
 
 #ifdef QUIC_TEST_DATAPATH_HOOKS_ENABLED
@@ -2372,23 +2374,83 @@ TEST(Misc, StreamMultiReceive) {
     }
 }
 
-TEST(Misc, StreamAppProvidedBuffers) {
-    TestLogger Logger("StreamAppProvidedBuffers");
+// App-provided receive buffer tests
+
+struct WithAppProvidedBuffersConfigArgs: public testing::TestWithParam<AppProvidedBuffersConfig> {
+    static ::std::vector<AppProvidedBuffersConfig> Generate() {
+        return {
+            { 8, 0x500, 8, 0x500}, // Base scenario
+            { 1, 100, 1, 100}, // Small buffers
+            { 150, 0x50, 150, 0x50}, // Many buffers
+        };
+    }
+};
+
+std::ostream& operator << (std::ostream& o, const AppProvidedBuffersConfig& args) {
+    return o <<
+        "Start:" << args.StreamStartBuffersNum << " buffers of" << args.StreamStartBuffersSize << "bytes," <<
+        "Additional:" << args.AdditionalBuffersNum << " buffers of " << args.AdditionalBuffersSize << "bytes.";
+}
+
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffers_ClientSend) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffers_ClientSend", GetParam());
+    if (TestingKernelMode) {
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffers_ClientSend), GetParam()));
+    } else {
+        QuicTestStreamAppProvidedBuffers_ClientSend(GetParam());
+    }
+}
+
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffers_ServerSend) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffers_ServerSend", GetParam());
+    if (TestingKernelMode) {
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffers_ServerSend), GetParam()));
+    } else {
+        QuicTestStreamAppProvidedBuffers_ServerSend(GetParam());
+    }
+}
+
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream", GetParam());
+    if (TestingKernelMode) {
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream), GetParam()));
+    } else {
+        QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream(GetParam());
+    }
+}
+
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer", GetParam());
+    if (TestingKernelMode) {
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer), GetParam()));
+    } else {
+        QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer(GetParam());
+    }
+}
+
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream", GetParam());
     if (TestingKernelMode) {
-        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffers)));
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream), GetParam()));
     } else {
-        QuicTestStreamAppProvidedBuffers();
+        QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream(GetParam());
     }
 }
 
-TEST(Misc, StreamAppProvidedBuffersOutOfSpace) {
-    TestLogger Logger("QuicTestStreamAppProvidedBuffersOutOfSpace");
+TEST_P(WithAppProvidedBuffersConfigArgs, StreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer) {
+    TestLoggerT<ParamType> Logger("StreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer", GetParam());
     if (TestingKernelMode) {
-        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffersOutOfSpace)));
+        ASSERT_TRUE(InvokeKernelTest(FUNC(QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer), GetParam()));
     } else {
-        QuicTestStreamAppProvidedBuffersOutOfSpace();
+        QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer(GetParam());
     }
 }
+
+INSTANTIATE_TEST_SUITE_P(
+    Misc,
+    WithAppProvidedBuffersConfigArgs,
+    testing::ValuesIn(WithAppProvidedBuffersConfigArgs::Generate()));
+
 #endif // QUIC_API_ENABLE_PREVIEW_FEATURES
 
 TEST(Misc, StreamBlockUnblockUnidiConnFlowControl) {

src/test/bin/winkernel/control.cpp

@@ -762,8 +762,12 @@ ExecuteTestRequest(
     RegisterTestFunction(QuicTestStreamReliableResetMultipleSends);
 #endif
     RegisterTestFunction(QuicTestTlsHandshakeInfo);
-    RegisterTestFunction(QuicTestStreamAppProvidedBuffers);
-    RegisterTestFunction(QuicTestStreamAppProvidedBuffersOutOfSpace);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffers_ClientSend);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffers_ServerSend);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_AbortStream);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffersOutOfSpace_ClientSend_ProvideMoreBuffer);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_AbortStream);
+    RegisterTestFunction(QuicTestStreamAppProvidedBuffersOutOfSpace_ServerSend_ProvideMoreBuffer);
 
     // Fail if no function matched
     char Buffer[256];