More progress. Host can now see the client that has joined. Host reacts to networked messages.

src/instance/game_instance.c

@@ -5,7 +5,7 @@
 #define INPUT_QUEUE_CAPACITY 8
 
 void game_instance_init(Game_Instance *instance) {
-    instance->local_player_index = 0xFFFF;
+    instance->local_player_id = 0xFFFF;
     // TODO: SS - Init input-queue.
     instance->simulation_accumulator = 0.0f; // TODO: SS - Should probably be moved to the Ingame context.
     instance->game_session = NULL;
@@ -38,18 +38,24 @@ bool game_instance_host_session(Game_Instance *instance, const Game_Session_Sett
             return false;
         }
         
-        if(!networking_try_host(&instance->game_networking, instance->game_session, settings)) {
+        uint16_t host_player_id = 0xFFFF;
+        if(!networking_try_host(&instance->game_networking, instance->game_session, settings, &host_player_id)) {
             printf("Failed to host session.\n");
             free(instance->game_session);
             instance->game_session = NULL;
             return false;
         }
+        
+        instance->local_player_id = host_player_id;
     }
     else {
         game_session_init(instance->game_session, settings);
-    }
 
-    assert(game_session_create_player(instance->game_session, &instance->local_player_index)); // Create the host (you!).
+        for(uint32_t i = 0; i < settings.max_players; i++) {
+            // When playing locally, create the player(s) here.
+            assert(game_session_create_player(instance->game_session, &instance->local_player_id)); // TODO: SS - Fix me! Always assigning the newest player to be the active 'local_player_id' which isn't correct.
+        }
+    }
         
     return true;
 }

src/instance/game_instance.h

@@ -9,7 +9,7 @@
 #include "shared/squeue.h"
 
 typedef struct {
-    uint16_t local_player_index;
+    uint16_t local_player_id;
     SQueue local_input_queue;
 
     double simulation_accumulator;

src/presentation/states/state_ingame.c

@@ -77,7 +77,7 @@ static void state_tick(Presentation_State *state) {
         if(game_instance_pop_local_input(instance, &input)) {
             // TODO: SS - We should probably check if this input is invalid for the snake. (pressing "go right" when going left, for example.)
             // If it is invalid, the next input in the queue should be tried.
-            game_session_set_player_input(session, instance->local_player_index, input);
+            game_session_set_player_input(session, instance->local_player_id, input);
         }
 
         game_session_tick(session);
@@ -299,7 +299,7 @@ static void state_render(Presentation_State *state) {
                 sim_world->game_world->seed,
                 sim_world->game_world->grid.width, sim_world->game_world->grid.height,
                 session->settings.tickrate,
-                instance->local_player_index, instance->local_player_index == 0 ? "true" : "false", // NOTE: SS - You're the host if you're player 0.
+                instance->local_player_id, instance->local_player_id == 0 ? "true" : "false", // NOTE: SS - You're the host if you're player 0.
                 game_session_get_amount_of_active_players(session), sim_world->max_players
             );
 

src/session/networking.c

@@ -6,15 +6,62 @@
 
 static void listen_callback(
     const char *event,      /* "joined", "leaved", "game" */
-    int64_t messageId,      /* sekventiellt meddelande‑ID (från host) */
-    const char *clientId,   /* avsändarens klient‑ID (eller NULL) */
+    int64_t messsage_id,      /* sekventiellt meddelande‑ID (från host) */
+    const char *client_id,   /* avsändarens klient‑ID (eller NULL) */
     json_t *data,           /* JSON‑objekt med godtycklig speldata */
     void *context         /* godtycklig pekare som skickas vidare */
 ) {
-    printf("#%li :: Event: '%s' from '%s'.\n", messageId, event, clientId);
-
     Game_Networking *networking = (Game_Networking *)context;
+    assert(networking != NULL);
+    assert(networking->game_session != NULL);
 
+    (void)data;
+
+    printf("#%li :: Event: '%s' from '%s'.\n", messsage_id, event, client_id);
+
+    assert(networking != NULL);
+
+    if(strcmp(event, "joined") == 0) {
+        // Create a new player in the session, get the id and store it as the value in the
+        // 'client_id_to_player_index' hashmap using 'client_id' as the key.
+        
+        uint32_t *existing_id = map_get(&networking->client_id_to_player_index, client_id);
+        assert(existing_id == NULL); // Something has gone terribly wrong if we get a 'joined' event for the same client-id with them still being in the map.
+        
+        uint16_t player_index = 0xFFFF;
+        assert(game_session_create_player(networking->game_session, &player_index));
+        assert(map_set(&networking->client_id_to_player_index, client_id, player_index) == 0); // 0 = OK.
+
+        // TODO: SS - Send a 'game' message to the joinee with information about the session?
+
+        printf("Added client-id '%s' (player-index: %u) to the map.\n", client_id, player_index);
+    }
+    else if(strcmp(event, "leaved") == 0) {
+        // TODO: SS - Index the hashmap using 'client_id' as the key and attempt to get the
+        // player-index for that client. Run 'game_session_destroy_player()'.
+
+        uint32_t *existing_id = map_get(&networking->client_id_to_player_index, client_id);
+        assert(existing_id != NULL); // Something has gone terribly wrong if we get a 'leaved' event for the a client-id that isn't in the map.
+        
+        uint16_t player_id_to_remove = *existing_id;
+        
+        game_session_destroy_player(networking->game_session, player_id_to_remove); // Returns void but crashes internally if id isn't OK.
+        map_remove(&networking->client_id_to_player_index, client_id);
+
+        printf("Removed client-id '%s' (player-index: %u) from the map.\n", client_id, player_id_to_remove);
+    }
+    else if(strcmp(event, "game") == 0) {
+        // TODO: SS - Check the 'data' to see what type of game-event it is.
+        // Possible game-events I can think of right now:
+        // - Player-input.
+        // - Match-state changed.
+        // - Chat-message?
+        // - Session-state?
+        // - Maybe Player-Joined/Left. (seems like mp_api only sends 'joined'/'leaved' events to the host.)
+    }
+    else {
+        printf("UNKNOWN EVENT-TYPE: '%s'.\n", event);
+    }
 }
 
 static inline bool setup_api(Game_Networking *networking) {
@@ -52,13 +99,14 @@ static bool start_listening(Game_Networking *networking) {
 static bool stop_listening(Game_Networking *networking) {
     assert(networking != NULL);
     assert(networking->api != NULL);
-    assert(networking->listener_id >= 0);
 
     mp_api_unlisten(networking->api, (int)networking->listener_id);
+    return true;
 }
 
-bool networking_try_host(Game_Networking *networking, Game_Session *session, Game_Session_Settings settings) {
+bool networking_try_host(Game_Networking *networking, Game_Session *session, Game_Session_Settings settings, uint16_t *out_host_player_id) {
     assert(networking != NULL);
+    assert(session != NULL);
 
     if(!settings.online) {
         printf("Failed to host; Game_Session_Settings.online == false, expected it to be true.\n");
@@ -87,9 +135,12 @@ bool networking_try_host(Game_Networking *networking, Game_Session *session, Gam
     }
     
     printf("Started hosting session '%s', local_client_id is '%s'.\n", session_id, local_client_id);
+    networking->game_session = session;
     networking->session_id = session_id;
     networking->local_client_id = local_client_id;
 
+    map_init(&networking->client_id_to_player_index);
+
     assert(start_listening(networking));
 
     // Set up session.
@@ -98,6 +149,13 @@ bool networking_try_host(Game_Networking *networking, Game_Session *session, Gam
         settings
     );
 
+    // Add the host to the game.
+    uint16_t host_player_index = 0xFFFF;
+    assert(game_session_create_player(networking->game_session, &host_player_index));
+    map_set(&networking->client_id_to_player_index, local_client_id, host_player_index);
+    *out_host_player_id = host_player_index;
+    printf("Host-player created (client-id: '%s'). Player-id: %u.\n", local_client_id, host_player_index);
+    
     if(response_data != NULL) {
         // TODO: SS - Handle JSON-response.
         json_decref(response_data);
@@ -108,6 +166,7 @@ bool networking_try_host(Game_Networking *networking, Game_Session *session, Gam
 
 bool networking_try_join(Game_Networking *networking, Game_Session *session, const char *session_id) {
     assert(networking != NULL);
+    assert(session != NULL);
 
     if(strlen(session_id) == 0) {
         return false;
@@ -127,7 +186,7 @@ bool networking_try_join(Game_Networking *networking, Game_Session *session, con
         networking->api, // API.
         session_id, // Session-code.
         NULL, // JSON-data to send. // TODO: SS - Send information about you as a player (username, ..).
-        &result_session_id, // Received Session-id. I assume it should be the same as 'session_id'.
+        &result_session_id, // Received Session-id. I assume it should be the same as 'session_id'. // TODO: SS - Ask Robin why mp_api_join() returns a session_id. Is it to support 'abcdef' => 'ABCDEF' and/or proxies?
         &local_client_id, // Received client-id.
         &received_json // Received JSON-data.
     );
@@ -136,14 +195,17 @@ bool networking_try_join(Game_Networking *networking, Game_Session *session, con
         printf("Failed to join; Got result: %i.\n", join_result);
         return false;
     }
-    assert(strcmp(result_session_id, session_id) == 0); // TODO: SS - Ask Robin why mp_api_join() returns a session_id. Is it to support 'abcdef' => 'ABCDEF'?
+    assert(strcmp(result_session_id, session_id) == 0);
 
     printf("Joined session '%s', local_client_id is '%s'.\n", result_session_id, local_client_id);
+    networking->game_session = session;
     networking->session_id = result_session_id;
     networking->local_client_id = local_client_id;
 
+    map_init(&networking->client_id_to_player_index);
+
     // TODO: SS - Decide how to network this..
-    // Should we just receive the session's settings as well as a long list of commands of what has happened throughout the match - at least one per tick?
+    // Should we just receive the session's settings as well as a long list of commands of what has happened throughout the match (so far) - at least one per tick?
     // Or, should this client receive the current state of the session?
 
     if(received_json != NULL) {
@@ -170,10 +232,13 @@ bool networking_stop_hosting(Game_Networking *networking) {
         return false;
     }
 
+    map_deinit(&networking->client_id_to_player_index);
+
     assert(stop_listening(networking));
 
     mp_api_destroy(networking->api);
     networking->api = NULL;
+    networking->session = NULL;
 
     if(networking->session_id != NULL) {
         free(networking->session_id);

src/session/networking.h

@@ -4,6 +4,8 @@
 #include "multiplayer_api.h"
 #include "game_session.h"
 
+#include "shared/map.h"
+
 typedef struct {
     MultiplayerApi *api;
 
@@ -11,9 +13,12 @@ typedef struct {
     char *local_client_id;
 
     uint32_t listener_id;
+
+    Game_Session *game_session; // Comes from Game_Instance.
+    map_uint_t client_id_to_player_index;
 } Game_Networking;
 
-bool networking_try_host(Game_Networking *networking, Game_Session *session, Game_Session_Settings settings);
+bool networking_try_host(Game_Networking *networking, Game_Session *session, Game_Session_Settings settings, uint16_t *out_host_player_id);
 bool networking_try_join(Game_Networking *networking, Game_Session *session, const char *session_id);
 
 bool networking_stop_hosting(Game_Networking *networking);

src/shared/map.c

@@ -0,0 +1,193 @@
+/** 
+ * Copyright (c) 2014 rxi
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the MIT license. See LICENSE for details.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include "map.h"
+
+struct map_node_t {
+  unsigned hash;
+  void *value;
+  map_node_t *next;
+  /* char key[]; */
+  /* char value[]; */
+};
+
+
+static unsigned map_hash(const char *str) {
+  unsigned hash = 5381;
+  while (*str) {
+    hash = ((hash << 5) + hash) ^ *str++;
+  }
+  return hash;
+}
+
+
+static map_node_t *map_newnode(const char *key, void *value, int vsize) {
+  map_node_t *node;
+  int ksize = strlen(key) + 1;
+  int voffset = ksize + ((sizeof(void*) - ksize) % sizeof(void*));
+  node = malloc(sizeof(*node) + voffset + vsize);
+  if (!node) return NULL;
+  memcpy(node + 1, key, ksize);
+  node->hash = map_hash(key);
+  node->value = ((char*) (node + 1)) + voffset;
+  memcpy(node->value, value, vsize);
+  return node;
+}
+
+
+static int map_bucketidx(map_base_t *m, unsigned hash) {
+  /* If the implementation is changed to allow a non-power-of-2 bucket count,
+   * the line below should be changed to use mod instead of AND */
+  return hash & (m->nbuckets - 1);
+}
+
+
+static void map_addnode(map_base_t *m, map_node_t *node) {
+  int n = map_bucketidx(m, node->hash);
+  node->next = m->buckets[n];
+  m->buckets[n] = node;
+}
+
+
+static int map_resize(map_base_t *m, int nbuckets) {
+  map_node_t *nodes, *node, *next;
+  map_node_t **buckets;
+  int i; 
+  /* Chain all nodes together */
+  nodes = NULL;
+  i = m->nbuckets;
+  while (i--) {
+    node = (m->buckets)[i];
+    while (node) {
+      next = node->next;
+      node->next = nodes;
+      nodes = node;
+      node = next;
+    }
+  }
+  /* Reset buckets */
+  buckets = realloc(m->buckets, sizeof(*m->buckets) * nbuckets);
+  if (buckets != NULL) {
+    m->buckets = buckets;
+    m->nbuckets = nbuckets;
+  }
+  if (m->buckets) {
+    memset(m->buckets, 0, sizeof(*m->buckets) * m->nbuckets);
+    /* Re-add nodes to buckets */
+    node = nodes;
+    while (node) {
+      next = node->next;
+      map_addnode(m, node);
+      node = next;
+    }
+  }
+  /* Return error code if realloc() failed */
+  return (buckets == NULL) ? -1 : 0;
+}
+
+
+static map_node_t **map_getref(map_base_t *m, const char *key) {
+  unsigned hash = map_hash(key);
+  map_node_t **next;
+  if (m->nbuckets > 0) {
+    next = &m->buckets[map_bucketidx(m, hash)];
+    while (*next) {
+      if ((*next)->hash == hash && !strcmp((char*) (*next + 1), key)) {
+        return next;
+      }
+      next = &(*next)->next;
+    }
+  }
+  return NULL;
+}
+
+
+void map_deinit_(map_base_t *m) {
+  map_node_t *next, *node;
+  int i;
+  i = m->nbuckets;
+  while (i--) {
+    node = m->buckets[i];
+    while (node) {
+      next = node->next;
+      free(node);
+      node = next;
+    }
+  }
+  free(m->buckets);
+}
+
+
+void *map_get_(map_base_t *m, const char *key) {
+  map_node_t **next = map_getref(m, key);
+  return next ? (*next)->value : NULL;
+}
+
+
+int map_set_(map_base_t *m, const char *key, void *value, int vsize) {
+  int n, err;
+  map_node_t **next, *node;
+  /* Find & replace existing node */
+  next = map_getref(m, key);
+  if (next) {
+    memcpy((*next)->value, value, vsize);
+    return 0;
+  }
+  /* Add new node */
+  node = map_newnode(key, value, vsize);
+  if (node == NULL) goto fail;
+  if (m->nnodes >= m->nbuckets) {
+    n = (m->nbuckets > 0) ? (m->nbuckets << 1) : 1;
+    err = map_resize(m, n);
+    if (err) goto fail;
+  }
+  map_addnode(m, node);
+  m->nnodes++;
+  return 0;
+  fail:
+  if (node) free(node);
+  return -1;
+}
+
+
+void map_remove_(map_base_t *m, const char *key) {
+  map_node_t *node;
+  map_node_t **next = map_getref(m, key);
+  if (next) {
+    node = *next;
+    *next = (*next)->next;
+    free(node);
+    m->nnodes--;
+  }
+}
+
+
+map_iter_t map_iter_(void) {
+  map_iter_t iter;
+  iter.bucketidx = -1;
+  iter.node = NULL;
+  return iter;
+}
+
+
+const char *map_next_(map_base_t *m, map_iter_t *iter) {
+  if (iter->node) {
+    iter->node = iter->node->next;
+    if (iter->node == NULL) goto nextBucket;
+  } else {
+    nextBucket:
+    do {
+      if (++iter->bucketidx >= m->nbuckets) {
+        return NULL;
+      }
+      iter->node = m->buckets[iter->bucketidx];
+    } while (iter->node == NULL);
+  }
+  return (char*) (iter->node + 1);
+}

src/shared/map.h

@@ -0,0 +1,78 @@
+/** 
+ * Copyright (c) 2014 rxi
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the MIT license. See LICENSE for details.
+ */
+
+#ifndef MAP_H
+#define MAP_H
+
+#include <string.h>
+
+#define MAP_VERSION "0.1.0"
+
+struct map_node_t;
+typedef struct map_node_t map_node_t;
+
+typedef struct {
+  map_node_t **buckets;
+  unsigned nbuckets, nnodes;
+} map_base_t;
+
+typedef struct {
+  unsigned bucketidx;
+  map_node_t *node;
+} map_iter_t;
+
+
+#define map_t(T)\
+  struct { map_base_t base; T *ref; T tmp; }
+
+
+#define map_init(m)\
+  memset(m, 0, sizeof(*(m)))
+
+
+#define map_deinit(m)\
+  map_deinit_(&(m)->base)
+
+
+#define map_get(m, key)\
+  ( (m)->ref = map_get_(&(m)->base, key) )
+
+
+#define map_set(m, key, value)\
+  ( (m)->tmp = (value),\
+    map_set_(&(m)->base, key, &(m)->tmp, sizeof((m)->tmp)) )
+
+
+#define map_remove(m, key)\
+  map_remove_(&(m)->base, key)
+
+
+#define map_iter(m)\
+  map_iter_()
+
+
+#define map_next(m, iter)\
+  map_next_(&(m)->base, iter)
+
+
+void map_deinit_(map_base_t *m);
+void *map_get_(map_base_t *m, const char *key);
+int map_set_(map_base_t *m, const char *key, void *value, int vsize);
+void map_remove_(map_base_t *m, const char *key);
+map_iter_t map_iter_(void);
+const char *map_next_(map_base_t *m, map_iter_t *iter);
+
+
+typedef map_t(void*) map_void_t;
+typedef map_t(char*) map_str_t;
+typedef map_t(int) map_int_t;
+typedef map_t(unsigned int) map_uint_t;
+typedef map_t(char) map_char_t;
+typedef map_t(float) map_float_t;
+typedef map_t(double) map_double_t;
+
+#endif