a much of multicasting stuff

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 120 insertions, 0 deletions

diff --git a/src/mds-server/multicast.h b/src/mds-server/multicast.h
new file mode 100644
index 0000000..3ea1e07
--- /dev/null
+++ b/src/mds-server/multicast.h
@@ -0,0 +1,120 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MDS_MDS_SERVER_MULTICAST_H
+#define MDS_MDS_SERVER_MULTICAST_H
+
+
+#include "queued_interception.h"
+
+
+/**
+ * Message multicast state
+ */
+typedef struct multicast
+{
+  /**
+   * Queue of clients that is listening this message
+   */
+  struct queued_interception* interceptions;
+  
+  /**
+   * The number of clients in `interceptions`
+   */
+  size_t interceptions_count;
+  
+  /**
+   * The index of the current/next client in `interceptions` to whom to send the message
+   */
+  size_t interceptions_ptr;
+  
+  /**
+   * The message to send
+   */
+  char* message;
+  
+  /**
+   * The length of `message`
+   */
+  size_t message_length;
+  
+  /**
+   * How much of the message that has already been sent to the current recipient
+   */
+  size_t message_ptr;
+  
+  /**
+   * How much of the message to skip if the recipient is not a modifier
+   */
+  size_t message_prefix;
+  
+} multicast_t;
+
+
+/**
+ * Initialise a message multicast state
+ * 
+ * @param  this  The message multicast state
+ */
+void multicast_initialise(multicast_t* restrict this);
+
+/**
+ * Destroy a message multicast state
+ * 
+ * @param  this  The message multicast state
+ */
+void multicast_destroy(multicast_t* restrict this);
+
+/**
+ * Calculate the buffer size need to marshal a message multicast state
+ * 
+ * @param   this  The client information
+ * @return        The number of bytes to allocate to the output buffer
+ */
+size_t multicast_marshal_size(const multicast_t* restrict this) __attribute__((pure));
+
+/**
+ * Marshals a message multicast state
+ * 
+ * @param   this  The message multicast state
+ * @param   data  Output buffer for the marshalled data
+ * @return        The number of bytes that have been written (everything will be written)
+ */
+size_t multicast_marshal(const multicast_t* restrict this, char* restrict data);
+
+/**
+ * Unmarshals a message multicast state
+ * 
+ * @param   this  Memory slot in which to store the new message multicast state
+ * @param   data  In buffer with the marshalled data
+ * @return        Zero on error, errno will be set accordingly, otherwise the number of read bytes.
+ *                Destroy the message multicast state on error.
+ */
+size_t multicast_unmarshal(multicast_t* restrict this, char* restrict data);
+
+/**
+ * Pretend to unmarshal a message multicast state
+ * 
+ * @param   data  In buffer with the marshalled data
+ * @return        The number of read bytes
+ */
+size_t multicast_unmarshal_skip(char* restrict data) __attribute__((pure));
+
+
+
+#endif
+