drop empty buffers

8 files changed, 39 insertions, 0 deletions

diff --git a/vespalib/src/vespa/vespalib/data/smart_buffer.cpp b/vespalib/src/vespa/vespalib/data/smart_buffer.cpp
index 401b6729601..4c3a3e6f379 100644
--- a/vespalib/src/vespa/vespalib/data/smart_buffer.cpp
+++ b/vespalib/src/vespa/vespalib/data/smart_buffer.cpp
@@ -23,6 +23,15 @@ SmartBuffer::ensure_free(size_t bytes)
     _read_pos = 0;
 }
 
+void
+SmartBuffer::drop()
+{
+    alloc::Alloc empty_buf;
+    _data.swap(empty_buf);
+    _read_pos = 0;
+    _write_pos = 0;
+}
+
 SmartBuffer::SmartBuffer(size_t initial_size)
     : _data(alloc::Alloc::alloc(initial_size)),
       _read_pos(0),
diff --git a/vespalib/src/vespa/vespalib/data/smart_buffer.h b/vespalib/src/vespa/vespalib/data/smart_buffer.h
index f7c4dd05c3e..c63c948b07d 100644
--- a/vespalib/src/vespa/vespalib/data/smart_buffer.h
+++ b/vespalib/src/vespa/vespalib/data/smart_buffer.h
@@ -28,10 +28,17 @@ private:
     size_t unused() const { return (_data.size() - read_len()); }
     void ensure_free(size_t bytes);
 
+    void drop();
+
 public:
     SmartBuffer(size_t initial_size);
     ~SmartBuffer();
     size_t capacity() const { return _data.size(); }
+    void drop_if_empty() {
+        if ((read_len() == 0) && (_data.size() > 0)) {
+            drop();
+        }
+    }
     Memory obtain() override;
     Input &evict(size_t bytes) override;
     WritableMemory reserve(size_t bytes) override;
diff --git a/vespalib/src/vespa/vespalib/net/crypto_engine.cpp b/vespalib/src/vespa/vespalib/net/crypto_engine.cpp
index 81ff28f17a1..a59bc6a9869 100644
--- a/vespalib/src/vespa/vespalib/net/crypto_engine.cpp
+++ b/vespalib/src/vespa/vespalib/net/crypto_engine.cpp
@@ -53,6 +53,7 @@ public:
     ssize_t write(const char *buf, size_t len) override { return _socket.write(buf, len); }
     ssize_t flush() override { return 0; }
     ssize_t half_close() override { return _socket.half_close(); }
+    void drop_empty_buffers() override {}
 };
 
 class XorCryptoSocket : public CryptoSocket
@@ -186,6 +187,10 @@ public:
         }
         return _socket.half_close();
     }
+    void drop_empty_buffers() override {
+        _input.drop_if_empty();
+        _output.drop_if_empty();
+    }
 };
 
 using net::tls::AuthorizationMode;
diff --git a/vespalib/src/vespa/vespalib/net/crypto_socket.h b/vespalib/src/vespa/vespalib/net/crypto_socket.h
index d51a97e2743..91af71296de 100644
--- a/vespalib/src/vespa/vespalib/net/crypto_socket.h
+++ b/vespalib/src/vespa/vespalib/net/crypto_socket.h
@@ -136,6 +136,13 @@ struct CryptoSocket {
      **/
     virtual ssize_t half_close() = 0;
 
+    /**
+     * This function can be called at any time to drop any currently
+     * empty internal buffers. Typically called after drain or flush
+     * indicates that no further progress can be made.
+     **/
+    virtual void drop_empty_buffers() = 0;
+
     virtual ~CryptoSocket();
 };
 
diff --git a/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.cpp b/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.cpp
index 660eee95132..4c0533a409a 100644
--- a/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.cpp
+++ b/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.cpp
@@ -201,4 +201,11 @@ CryptoCodecAdapter::half_close()
     return _socket.half_close();
 }
 
+void
+CryptoCodecAdapter::drop_empty_buffers()
+{
+    _input.drop_if_empty();
+    _output.drop_if_empty();
+}
+
 } // namespace vespalib::net::tls
diff --git a/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.h b/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.h
index a31e8c5dfed..372a2191a88 100644
--- a/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.h
+++ b/vespalib/src/vespa/vespalib/net/tls/crypto_codec_adapter.h
@@ -45,6 +45,7 @@ public:
     ssize_t write(const char *buf, size_t len) override;
     ssize_t flush() override;
     ssize_t half_close() override;
+    void drop_empty_buffers() override;
 };
 
 } // namespace vespalib::net::tls
diff --git a/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.cpp b/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.cpp
index d5ab1113013..3035387e4f0 100644
--- a/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.cpp
+++ b/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.cpp
@@ -77,12 +77,14 @@ public:
         if (frame > 0) {
             memcpy(buf, src.data, frame);
             _buffer.evict(frame);
+            _buffer.drop_if_empty();
         }
         return frame;
     }
     ssize_t write(const char *buf, size_t len) override { return _socket.write(buf, len); }
     ssize_t flush() override { return 0; }
     ssize_t half_close() override { return _socket.half_close(); }
+    void drop_empty_buffers() override {}
 };
 
 } // namespace vespalib::<unnamed>
diff --git a/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.h b/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.h
index cd2d84bcc08..2768bc0fc52 100644
--- a/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.h
+++ b/vespalib/src/vespa/vespalib/net/tls/maybe_tls_crypto_socket.h
@@ -32,6 +32,7 @@ public:
     ssize_t write(const char *buf, size_t len) override { return _socket->write(buf, len); }
     ssize_t flush() override { return _socket->flush(); }
     ssize_t half_close() override { return _socket->half_close(); }
+    void drop_empty_buffers() override { _socket->drop_empty_buffers(); }
 };
 
 } // namespace vespalib