flow: add StreamPassConnector

flow/CMakeLists.txt

@@ -25,5 +25,6 @@ add_library(flow
     SingleStreamSender.c
     SingleStreamReceiver.c
     StreamPacketSender.c
+    StreamPassConnector.c
 )
 target_link_libraries(flow base)

flow/StreamPassConnector.c

@@ -0,0 +1,113 @@
+/**
+ * @file StreamPassConnector.c
+ * @author Ambroz Bizjak <ambrop7@gmail.com>
+ * 
+ * @section LICENSE
+ * 
+ * This file is part of BadVPN.
+ * 
+ * BadVPN is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ * 
+ * BadVPN is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stddef.h>
+
+#include <misc/debug.h>
+
+#include <flow/StreamPassConnector.h>
+
+static void input_handler_send (StreamPassConnector *o, uint8_t *data, int data_len)
+{
+    ASSERT(data_len > 0)
+    ASSERT(o->in_len == -1)
+    DebugObject_Access(&o->d_obj);
+    
+    // remember input packet
+    o->in_len = data_len;
+    o->in = data;
+    
+    if (o->output) {
+        // schedule send
+        StreamPassInterface_Sender_Send(o->output, o->in, o->in_len);
+    }
+}
+
+static void output_handler_done (StreamPassConnector *o, int data_len)
+{
+    ASSERT(data_len > 0)
+    ASSERT(data_len <= o->in_len)
+    ASSERT(o->in_len > 0)
+    ASSERT(o->output)
+    DebugObject_Access(&o->d_obj);
+    
+    // have no input packet
+    o->in_len = -1;
+    
+    // allow input to send more packets
+    StreamPassInterface_Done(&o->input, data_len);
+}
+
+void StreamPassConnector_Init (StreamPassConnector *o, BPendingGroup *pg)
+{
+    // init output
+    StreamPassInterface_Init(&o->input, (StreamPassInterface_handler_send)input_handler_send, o, pg);
+    
+    // have no input packet
+    o->in_len = -1;
+    
+    // have no output
+    o->output = NULL;
+    
+    DebugObject_Init(&o->d_obj);
+}
+
+void StreamPassConnector_Free (StreamPassConnector *o)
+{
+    DebugObject_Free(&o->d_obj);
+    
+    // free output
+    StreamPassInterface_Free(&o->input);
+}
+
+StreamPassInterface * StreamPassConnector_GetInput (StreamPassConnector *o)
+{
+    DebugObject_Access(&o->d_obj);
+    
+    return &o->input;
+}
+
+void StreamPassConnector_ConnectOutput (StreamPassConnector *o, StreamPassInterface *output)
+{
+    ASSERT(!o->output)
+    DebugObject_Access(&o->d_obj);
+    
+    // set output
+    o->output = output;
+    
+    // init output
+    StreamPassInterface_Sender_Init(o->output, (StreamPassInterface_handler_done)output_handler_done, o);
+    
+    // if we have an input packet, schedule send
+    if (o->in_len > 0) {
+        StreamPassInterface_Sender_Send(o->output, o->in, o->in_len);
+    }
+}
+
+void StreamPassConnector_DisconnectOutput (StreamPassConnector *o)
+{
+    ASSERT(o->output)
+    DebugObject_Access(&o->d_obj);
+    
+    // set no output
+    o->output = NULL;
+}

flow/StreamPassConnector.h

@@ -0,0 +1,91 @@
+/**
+ * @file StreamPassConnector.h
+ * @author Ambroz Bizjak <ambrop7@gmail.com>
+ * 
+ * @section LICENSE
+ * 
+ * This file is part of BadVPN.
+ * 
+ * BadVPN is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ * 
+ * BadVPN is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * @section DESCRIPTION
+ * 
+ * A {@link StreamPassInterface} layer which allows the output to be
+ * connected and disconnected on the fly.
+ */
+
+#ifndef BADVPN_FLOW_STREAMPASSCONNECTOR_H
+#define BADVPN_FLOW_STREAMPASSCONNECTOR_H
+
+#include <stdint.h>
+
+#include <base/DebugObject.h>
+#include <flow/StreamPassInterface.h>
+
+/**
+ * A {@link StreamPassInterface} layer which allows the output to be
+ * connected and disconnected on the fly.
+ */
+typedef struct {
+    StreamPassInterface input;
+    int in_len;
+    uint8_t *in;
+    StreamPassInterface *output;
+    DebugObject d_obj;
+} StreamPassConnector;
+
+/**
+ * Initializes the object.
+ * The object is initialized in not connected state.
+ *
+ * @param o the object
+ * @param pg pending group
+ */
+void StreamPassConnector_Init (StreamPassConnector *o, BPendingGroup *pg);
+
+/**
+ * Frees the object.
+ *
+ * @param o the object
+ */
+void StreamPassConnector_Free (StreamPassConnector *o);
+
+/**
+ * Returns the input interface.
+ *
+ * @param o the object
+ * @return input interface
+ */
+StreamPassInterface * StreamPassConnector_GetInput (StreamPassConnector *o);
+
+/**
+ * Connects output.
+ * The object must be in not connected state.
+ * The object enters connected state.
+ *
+ * @param o the object
+ * @param output output to connect
+ */
+void StreamPassConnector_ConnectOutput (StreamPassConnector *o, StreamPassInterface *output);
+
+/**
+ * Disconnects output.
+ * The object must be in connected state.
+ * The object enters not connected state.
+ *
+ * @param o the object
+ */
+void StreamPassConnector_DisconnectOutput (StreamPassConnector *o);
+
+#endif