Improvements to matchmaking system

hm_lobbyserver/src/game.c

@@ -15,66 +15,73 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#include <stdio.h>
-#include <stdarg.h>
-#include <memory.h>
-#include <malloc.h>
 #include <ev.h>
+#include <malloc.h>
+#include <memory.h>
+#include <stdarg.h>
+#include <stdio.h>
 
 #include <hmbase.h>
 
 #include <client.h>
 
 struct playerlist_s {
-    struct conn_client_s *player;
+  struct conn_client_s *player;
-    struct playerlist_s *next;
+  struct playerlist_s *next;
 };
 
-static struct playerlist_s *queue = NULL;
 static int gamehandle = 0;
+struct playerlist_s *queue = NULL;
+struct playerlist_s *tail = NULL; // Pointer to the last element
 
-void mm_push(struct conn_client_s *c)
+// Add a player to the matchmaking queue
-{
+void mm_push(struct conn_client_s *c) {
-    struct playerlist_s *p;
+  struct playerlist_s *p = malloc(sizeof(*p));
-
+  p->player = c;
-    p = malloc(sizeof(*p));
+  p->next = NULL;
-
-    p->player = c;
-    p->next = queue;
 
+  if (queue == NULL) {
     queue = p;
+  } else {
+    tail->next = p;
+  }
+
+  tail = p; // Update the tail pointer
 }
 
-struct conn_client_s *mm_pop()
+// Remove a player from the matchmaking queue
-{
+struct conn_client_s *mm_pop() {
-    struct conn_client_s *c;
+  if (queue == NULL)
-    struct playerlist_s *p;
+    return NULL;
 
-    p = queue;
+  struct playerlist_s *temp = queue;
-    c = queue->player;
+  struct conn_client_s *c = temp->player;
 
-    queue = queue->next;
+  queue = queue->next;
-    free(p);
+  if (queue == NULL) {
+    tail = NULL; // If the queue is empty after pop, reset the tail pointer
+  }
+  free(temp);
 
-    return c;
+  return c;
 }
 
-int matchmaking(struct conn_client_s *player1)
+// Matchmaking
-{
+int matchmaking(struct conn_client_s *player) {
-    struct conn_client_s *player2;	
+  // Add the player to the queue
+  mm_push(player);
 
-    // first player
+  while (queue != NULL && queue->next != NULL) {
-    if(queue == NULL) {
+    struct conn_client_s *player1 = mm_pop();
-        mm_push(player1);
+    struct conn_client_s *player2 = mm_pop();
-        return 0;
+
+    if (player1 && player2) {
+      start_game(player1, player2, gamehandle++);
+    } else {
+      // This block should  never be reached in this setup
+      return -1;
     }
+  }
 
-    player2 = mm_pop();
+  return 0;
-
-    if(player1 && player2) {
-        start_game(player1, player2, gamehandle++);
-        return 0;
-    }
-
-    return -1;
 }