Add server.[ch]

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 180 insertions, 0 deletions

diff --git a/src/server.c b/src/server.c
new file mode 100644
index 0000000..843ad81
--- /dev/null
+++ b/src/server.c
@@ -0,0 +1,180 @@
+/**
+ * gammad -- Cooperative gamma server
+ * Copyright (C) 2016  Mattias Andrée (maandree@kth.se)
+ * 
+ * This library 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 library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "server.h"
+#include "util.h"
+
+#include <sys/socket.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+
+/**
+ * List of all client's file descriptors
+ * 
+ * Unused slots, with index less than `connections_used`,
+ * should have the value -1 (negative)
+ */
+int* connections = NULL;
+
+/**
+ * The number of elements allocated for `connections`
+ */
+size_t connections_alloc = 0;
+
+/**
+ * The index of the first unused slot in `connections`
+ */
+size_t connections_ptr = 0;
+
+/**
+ * The index of the last used slot in `connections`, plus 1
+ */
+size_t connections_used = 0;
+
+/**
+ * The server connection's message buffer
+ */
+struct message server_message;
+
+/**
+ * The clients' connections' message buffers
+ */
+struct message* client_messages = NULL;
+
+/**
+ * The server socket's file descriptor
+ */
+extern int socketfd;
+
+
+
+/**
+ * Initialise the state of the connections
+ * 
+ * @param  Zero on success, -1 on error
+ */
+int server_initialise(void)
+{
+  return message_initialise(&server_message);
+}
+
+
+/**
+ * Destroy the state of the connections
+ * 
+ * @param  disconnect  Disconnect all connections?
+ */
+void server_destroy(int disconnect)
+{
+  size_t i;
+  
+  /* TODO */ (void) disconnect;
+  
+  for (i = 0; i < connections_used; i++)
+    if (connections[i] >= 0)
+      message_destroy(client_messages + i);
+  free(client_messages);
+  message_destroy(&server_message);
+  free(connections);
+}
+
+
+/**
+ * Marshal the state of the connections
+ * 
+ * @param   buf  Output buffer for the marshalled data,
+ *               `NULL` to only measure how many bytes
+ *               this buffer needs
+ * @return       The number of marshalled bytes
+ */
+size_t server_marshal(void* buf)
+{
+  size_t i, off = 0;
+  char* bs = buf;
+  
+  if (bs != NULL)
+    *(size_t*)(bs + off) = connections_ptr;
+  off += sizeof(size_t);
+  
+  if (bs != NULL)
+    *(size_t*)(bs + off) = connections_used;
+  off += sizeof(size_t);
+  
+  if (bs != NULL)
+    memcpy(bs + off, connections, connections_used * sizeof(*connections));
+  off += connections_used * sizeof(*connections);
+  
+  off += message_marshal(&server_message, bs ? bs + off : NULL);
+  
+  for (i = 0; i < connections_used; i++)
+    if (connections[i] >= 0)
+      off += message_marshal(client_messages + i, bs ? bs + off : NULL);
+  
+  return off;
+}
+
+
+/**
+ * Unmarshal the state of the connections
+ * 
+ * @param   buf  Buffer for the marshalled data
+ * @return       The number of unmarshalled bytes, 0 on error
+ */
+size_t server_unmarshal(const void* buf)
+{
+  size_t off = 0, i, n;
+  const char* bs = buf;
+  
+  connections = NULL;
+  client_messages = NULL;
+  memset(&server_message, 0, sizeof(server_message));
+  
+  connections_ptr = *(const size_t*)(bs + off);
+  off += sizeof(size_t);
+  
+  connections_alloc = connections_used = *(const size_t*)(bs + off);
+  off += sizeof(size_t);
+  
+  if (connections_alloc > 0)
+    {
+      connections = memdup(bs + off, connections_alloc * sizeof(*connections));
+      if (connections == NULL)
+	return 0;
+      off += connections_used * sizeof(*connections);
+      
+      client_messages = malloc(connections_alloc * sizeof(*client_messages));
+      if (client_messages == NULL)
+	return 0;
+    }
+  
+  off += n = message_unmarshal(&server_message, bs + off);
+  if (n == 0)
+    return 0;
+  
+  for (i = 0; i < connections_used; i++)
+    if (connections[i] >= 0)
+      {
+	off += n = message_unmarshal(client_messages + i, bs ? bs + off : NULL);
+	if (n == 0)
+	  return 0;
+      }
+  
+  return off;
+}
+