Limit number of group chats to 65536.

By changing numchats from uint32_t to uint16_t. This is done in PGC. This
PR is making that change in master to reduce the diff in the PGC branch.

Also:
* Inverted groupnumber_not_valid and renamed to is_groupnumber_valid.
* Renamed realloc_groupchats to realloc_conferences and made it return bool.
* Added setup_conference function that currently just zeroes the
  conference structure but later will initialise more values.
* Made some `i` iterator variables local to the for-loop using
  for-init-decl. This is also done in PGC.

1 files changed, 44 insertions, 61 deletions

diff --git a/toxcore/group.c b/toxcore/group.c
index a2ebca16..3e0c1fd3 100644
--- a/toxcore/group.c
+++ b/toxcore/group.c
@@ -33,72 +33,74 @@
 #include "mono_time.h"
 #include "util.h"
 
-/* return 1 if the groupnumber is not valid.
- * return 0 if the groupnumber is valid.
+/* return false if the groupnumber is not valid.
+ * return true if the groupnumber is valid.
  */
-static uint8_t groupnumber_not_valid(const Group_Chats *g_c, uint32_t groupnumber)
+static bool is_groupnumber_valid(const Group_Chats *g_c, uint32_t groupnumber)
 {
     if (groupnumber >= g_c->num_chats) {
-        return 1;
+        return false;
     }
 
     if (g_c->chats == nullptr) {
-        return 1;
+        return false;
     }
 
     if (g_c->chats[groupnumber].status == GROUPCHAT_STATUS_NONE) {
-        return 1;
+        return false;
     }
 
-    return 0;
+    return true;
 }
 
 
 /* Set the size of the groupchat list to num.
  *
- *  return -1 if realloc fails.
- *  return 0 if it succeeds.
+ *  return false if realloc fails.
+ *  return true if it succeeds.
  */
-static int realloc_groupchats(Group_Chats *g_c, uint32_t num)
+static bool realloc_conferences(Group_Chats *g_c, uint16_t num)
 {
     if (num == 0) {
         free(g_c->chats);
         g_c->chats = nullptr;
-        return 0;
+        return true;
     }
 
     Group_c *newgroup_chats = (Group_c *)realloc(g_c->chats, num * sizeof(Group_c));
 
     if (newgroup_chats == nullptr) {
-        return -1;
+        return false;
     }
 
     g_c->chats = newgroup_chats;
-    return 0;
+    return true;
 }
 
+static void setup_conference(Group_c *g)
+{
+    memset(g, 0, sizeof(Group_c));
+}
 
 /* Create a new empty groupchat connection.
  *
  * return -1 on failure.
  * return groupnumber on success.
  */
-static int create_group_chat(Group_Chats *g_c)
+static int32_t create_group_chat(Group_Chats *g_c)
 {
-    uint32_t i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         if (g_c->chats[i].status == GROUPCHAT_STATUS_NONE) {
             return i;
         }
     }
 
-    int id = -1;
+    int32_t id = -1;
 
-    if (realloc_groupchats(g_c, g_c->num_chats + 1) == 0) {
+    if (realloc_conferences(g_c, g_c->num_chats + 1)) {
         id = g_c->num_chats;
         ++g_c->num_chats;
-        memset(&g_c->chats[id], 0, sizeof(Group_c));
+        setup_conference(&g_c->chats[id]);
     }
 
     return id;
@@ -112,11 +114,11 @@ static int create_group_chat(Group_Chats *g_c)
  */
 static int wipe_group_chat(Group_Chats *g_c, uint32_t groupnumber)
 {
-    if (groupnumber_not_valid(g_c, groupnumber)) {
+    if (!is_groupnumber_valid(g_c, groupnumber)) {
         return -1;
     }
 
-    uint32_t i;
+    uint16_t i;
     crypto_memzero(&g_c->chats[groupnumber], sizeof(Group_c));
 
     for (i = g_c->num_chats; i != 0; --i) {
@@ -127,7 +129,7 @@ static int wipe_group_chat(Group_Chats *g_c, uint32_t groupnumber)
 
     if (g_c->num_chats != i) {
         g_c->num_chats = i;
-        realloc_groupchats(g_c, g_c->num_chats);
+        realloc_conferences(g_c, g_c->num_chats);
     }
 
     return 0;
@@ -135,7 +137,7 @@ static int wipe_group_chat(Group_Chats *g_c, uint32_t groupnumber)
 
 static Group_c *get_group_c(const Group_Chats *g_c, uint32_t groupnumber)
 {
-    if (groupnumber_not_valid(g_c, groupnumber)) {
+    if (!is_groupnumber_valid(g_c, groupnumber)) {
         return nullptr;
     }
 
@@ -153,9 +155,7 @@ static Group_c *get_group_c(const Group_Chats *g_c, uint32_t groupnumber)
 
 static int peer_in_chat(const Group_c *chat, const uint8_t *real_pk)
 {
-    uint32_t i;
-
-    for (i = 0; i < chat->numpeers; ++i) {
+    for (uint32_t i = 0; i < chat->numpeers; ++i) {
         if (id_equal(chat->group[i].real_pk, real_pk)) {
             return i;
         }
@@ -172,11 +172,9 @@ static int peer_in_chat(const Group_c *chat, const uint8_t *real_pk)
  *
  * TODO(irungentoo): make this more efficient and maybe use constant time comparisons?
  */
-static int get_group_num(const Group_Chats *g_c, const uint8_t *identifier)
+static int32_t get_group_num(const Group_Chats *g_c, const uint8_t *identifier)
 {
-    uint32_t i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         if (crypto_memcmp(g_c->chats[i].identifier, identifier, GROUP_IDENTIFIER_LENGTH) == 0) {
             return i;
         }
@@ -195,9 +193,7 @@ static int get_group_num(const Group_Chats *g_c, const uint8_t *identifier)
  */
 static int get_peer_index(Group_c *g, uint16_t peer_number)
 {
-    uint32_t i;
-
-    for (i = 0; i < g->numpeers; ++i) {
+    for (uint32_t i = 0; i < g->numpeers; ++i) {
         if (g->group[i].peer_number == peer_number) {
             return i;
         }
@@ -345,15 +341,13 @@ static int connect_to_closest(Group_Chats *g_c, uint32_t groupnumber, void *user
         return 0;
     }
 
-    unsigned int i;
-
     if (g->changed == GROUPCHAT_CLOSEST_REMOVED) {
-        for (i = 0; i < g->numpeers; ++i) {
+        for (uint32_t i = 0; i < g->numpeers; ++i) {
             add_to_closest(g_c, groupnumber, g->group[i].real_pk, g->group[i].temp_pk);
         }
     }
 
-    for (i = 0; i < MAX_GROUP_CONNECTIONS; ++i) {
+    for (uint32_t i = 0; i < MAX_GROUP_CONNECTIONS; ++i) {
         if (g->close[i].type == GROUPCHAT_CLOSE_NONE) {
             continue;
         }
@@ -372,7 +366,7 @@ static int connect_to_closest(Group_Chats *g_c, uint32_t groupnumber, void *user
         }
     }
 
-    for (i = 0; i < DESIRED_CLOSE_CONNECTIONS; ++i) {
+    for (uint32_t i = 0; i < DESIRED_CLOSE_CONNECTIONS; ++i) {
         if (!g->closest_peers[i].entry) {
             continue;
         }
@@ -467,7 +461,7 @@ static int addpeer(Group_Chats *g_c, uint32_t groupnumber, const uint8_t *real_p
         g->peer_on_join(g->object, groupnumber, g->numpeers - 1);
     }
 
-    return (g->numpeers - 1);
+    return g->numpeers - 1;
 }
 
 static int remove_close_conn(Group_Chats *g_c, uint32_t groupnumber, int friendcon_id)
@@ -657,9 +651,7 @@ static void set_conns_type_close(Group_Chats *g_c, uint32_t groupnumber, int fri
 /* Set the type for all close connections with friendcon_id */
 static void set_conns_status_groups(Group_Chats *g_c, int friendcon_id, uint8_t type)
 {
-    uint32_t i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         set_conns_type_close(g_c, i, friendcon_id, type);
     }
 }
@@ -736,7 +728,7 @@ static int add_conn_to_groupchat(Group_Chats *g_c, int friendcon_id, uint32_t gr
  */
 int add_groupchat(Group_Chats *g_c, uint8_t type)
 {
-    int groupnumber = create_group_chat(g_c);
+    int32_t groupnumber = create_group_chat(g_c);
 
     if (groupnumber == -1) {
         return -1;
@@ -1629,7 +1621,7 @@ static unsigned int send_peers(Group_Chats *g_c, uint32_t groupnumber, int frien
     uint8_t *p = response_packet + 1;
 
     uint16_t sent = 0;
-    unsigned int i;
+    uint32_t i;
 
     for (i = 0; i < g->numpeers; ++i) {
         if ((p - response_packet) + sizeof(uint16_t) + CRYPTO_PUBLIC_KEY_SIZE * 2 + 1 + g->group[i].nick_len > sizeof(
@@ -2425,9 +2417,7 @@ static int groupchat_clear_timedout(Group_Chats *g_c, uint32_t groupnumber, void
         return -1;
     }
 
-    uint32_t i;
-
-    for (i = 0; i < g->numpeers; ++i) {
+    for (uint32_t i = 0; i < g->numpeers; ++i) {
         if (g->peer_number != g->group[i].peer_number && is_timeout(g->group[i].last_recv, GROUP_PING_INTERVAL * 3)) {
             delpeer(g_c, groupnumber, i, userdata);
         }
@@ -2444,9 +2434,7 @@ static int groupchat_clear_timedout(Group_Chats *g_c, uint32_t groupnumber, void
  */
 void send_name_all_groups(Group_Chats *g_c)
 {
-    unsigned int i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         Group_c *g = get_group_c(g_c, i);
 
         if (!g) {
@@ -2483,9 +2471,7 @@ Group_Chats *new_groupchats(Messenger *m)
 /* main groupchats loop. */
 void do_groupchats(Group_Chats *g_c, void *userdata)
 {
-    unsigned int i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         Group_c *g = get_group_c(g_c, i);
 
         if (!g) {
@@ -2505,9 +2491,7 @@ void do_groupchats(Group_Chats *g_c, void *userdata)
 /* Free everything related with group chats. */
 void kill_groupchats(Group_Chats *g_c)
 {
-    unsigned int i;
-
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         del_groupchat(g_c, i);
     }
 
@@ -2523,9 +2507,8 @@ void kill_groupchats(Group_Chats *g_c)
 uint32_t count_chatlist(Group_Chats *g_c)
 {
     uint32_t ret = 0;
-    uint32_t i;
 
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         if (g_c->chats[i].status != GROUPCHAT_STATUS_NONE) {
             ++ret;
         }
@@ -2549,9 +2532,9 @@ uint32_t copy_chatlist(Group_Chats *g_c, uint32_t *out_list, uint32_t list_size)
         return 0;
     }
 
-    uint32_t i, ret = 0;
+    uint32_t ret = 0;
 
-    for (i = 0; i < g_c->num_chats; ++i) {
+    for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         if (ret >= list_size) {
             break;  /* Abandon ship */
         }