cleanup: Avoid memset on structs.

Most of these were safe (some were not), but even the safe ones can
become unsafe (non-portable) later on when adding pointer or float members.

other/bootstrap_daemon/docker/tox-bootstrapd.sha256

@@ -1 +1 @@
-ba9c06f1079837ac20376c25bbf1411ddb6d8f86cc5c44cf58d053969b192653  /usr/local/bin/tox-bootstrapd
+43b84814203bd1cb2d169e60d893d85242a5e27ab7ca0d53534235630c377b40  /usr/local/bin/tox-bootstrapd

testing/BUILD.bazel

@@ -16,7 +16,6 @@ sh_test(
         "-Wno-boolean-return",
         "-Wno-callback-names",
         "-Wno-enum-names",
-        "-Wno-memcpy-structs",
         "-Wno-type-check",
         "+RTS",
         "-N3",

toxcore/DHT.c

@@ -68,6 +68,9 @@ struct DHT_Friend {
     unsigned int num_to_bootstrap;
 };
 
+static const DHT_Friend empty_dht_friend = {{0}};
+const Node_format empty_node_format = {{0}};
+
 typedef struct Cryptopacket_Handler {
     cryptopacket_handler_cb *function;
     void *object;
@@ -1652,7 +1655,7 @@ int dht_addfriend(DHT *dht, const uint8_t *public_key, dht_ip_cb *ip_callback,
 
     dht->friends_list = temp;
     DHT_Friend *const dht_friend = &dht->friends_list[dht->num_friends];
-    memset(dht_friend, 0, sizeof(DHT_Friend));
+    *dht_friend = empty_dht_friend;
     memcpy(dht_friend->public_key, public_key, CRYPTO_PUBLIC_KEY_SIZE);
 
     dht_friend->nat.nat_ping_id = random_u64();

toxcore/DHT.h

@@ -162,6 +162,8 @@ typedef struct Node_format {
     IP_Port     ip_port;
 } Node_format;
 
+extern const Node_format empty_node_format;
+
 typedef struct DHT_Friend DHT_Friend;
 
 non_null() const uint8_t *dht_friend_public_key(const DHT_Friend *dht_friend);

toxcore/Messenger.c

@@ -24,6 +24,8 @@
 static_assert(MAX_CONCURRENT_FILE_PIPES <= UINT8_MAX + 1,
               "uint8_t cannot represent all file transfer numbers");
 
+static const Friend empty_friend = {{0}};
+
 /** @brief Set the size of the friend list to numfriends.
  *
  * @retval -1 if realloc fails.
@@ -163,7 +165,7 @@ static int32_t init_new_friend(Messenger *m, const uint8_t *real_pk, uint8_t sta
         return FAERR_NOMEM;
     }
 
-    memset(&m->friendlist[m->numfriends], 0, sizeof(Friend));
+    m->friendlist[m->numfriends] = empty_friend;
 
     const int friendcon_id = new_friend_connection(m->fr_c, real_pk);
 
@@ -418,7 +420,7 @@ int m_delfriend(Messenger *m, int32_t friendnumber)
     }
 
     kill_friend_connection(m->fr_c, m->friendlist[friendnumber].friendcon_id);
-    memset(&m->friendlist[friendnumber], 0, sizeof(Friend));
+    m->friendlist[friendnumber] = empty_friend;
 
     uint32_t i;
 

toxcore/TCP_connection.c

@@ -47,6 +47,10 @@ struct TCP_Connections {
 };
 
 
+static const TCP_Connection_to empty_tcp_connection_to = {0};
+static const TCP_con empty_tcp_con = {0};
+
+
 const uint8_t *tcp_connections_public_key(const TCP_Connections *tcp_c)
 {
     return tcp_c->self_public_key;
@@ -158,7 +162,7 @@ static int create_connection(TCP_Connections *tcp_c)
     if (realloc_TCP_Connection_to(&tcp_c->connections, tcp_c->connections_length + 1) == 0) {
         id = tcp_c->connections_length;
         ++tcp_c->connections_length;
-        memset(&tcp_c->connections[id], 0, sizeof(TCP_Connection_to));
+        tcp_c->connections[id] = empty_tcp_connection_to;
     }
 
     return id;
@@ -183,7 +187,7 @@ static int create_tcp_connection(TCP_Connections *tcp_c)
     if (realloc_TCP_con(&tcp_c->tcp_connections, tcp_c->tcp_connections_length + 1) == 0) {
         id = tcp_c->tcp_connections_length;
         ++tcp_c->tcp_connections_length;
-        memset(&tcp_c->tcp_connections[id], 0, sizeof(TCP_con));
+        tcp_c->tcp_connections[id] = empty_tcp_con;
     }
 
     return id;
@@ -202,7 +206,7 @@ static int wipe_connection(TCP_Connections *tcp_c, int connections_number)
     }
 
     uint32_t i;
-    memset(&tcp_c->connections[connections_number], 0, sizeof(TCP_Connection_to));
+    tcp_c->connections[connections_number] = empty_tcp_connection_to;
 
     for (i = tcp_c->connections_length; i != 0; --i) {
         if (tcp_c->connections[i - 1].status != TCP_CONN_NONE) {
@@ -230,7 +234,7 @@ static int wipe_tcp_connection(TCP_Connections *tcp_c, int tcp_connections_numbe
         return -1;
     }
 
-    memset(&tcp_c->tcp_connections[tcp_connections_number], 0, sizeof(TCP_con));
+    tcp_c->tcp_connections[tcp_connections_number] = empty_tcp_con;
 
     uint32_t i;
 

toxcore/friend_connection.c

@@ -54,6 +54,8 @@ struct Friend_Conn {
     bool hosting_tcp_relay;
 };
 
+static const Friend_Conn empty_friend_conn = {0};
+
 
 struct Friend_Connections {
     const Mono_Time *mono_time;
@@ -151,7 +153,7 @@ static int create_friend_conn(Friend_Connections *fr_c)
 
     const int id = fr_c->num_cons;
     ++fr_c->num_cons;
-    memset(&fr_c->conns[id], 0, sizeof(Friend_Conn));
+    fr_c->conns[id] = empty_friend_conn;
 
     return id;
 }
@@ -168,7 +170,7 @@ static int wipe_friend_conn(Friend_Connections *fr_c, int friendcon_id)
         return -1;
     }
 
-    memset(&fr_c->conns[friendcon_id], 0, sizeof(Friend_Conn));
+    fr_c->conns[friendcon_id] = empty_friend_conn;
 
     uint32_t i;
 
@@ -245,7 +247,7 @@ static int friend_add_tcp_relay(Friend_Connections *fr_c, int friendcon_id, cons
     for (unsigned i = 0; i < FRIEND_MAX_STORED_TCP_RELAYS; ++i) {
         if (!net_family_is_unspec(friend_con->tcp_relays[i].ip_port.ip.family)
                 && pk_equal(friend_con->tcp_relays[i].public_key, public_key)) {
-            memset(&friend_con->tcp_relays[i], 0, sizeof(Node_format));
+            friend_con->tcp_relays[i] = empty_node_format;
         }
     }
 

toxcore/group.c

@@ -58,6 +58,9 @@ typedef enum Peer_Id {
 static_assert(GROUP_ID_LENGTH == CRYPTO_PUBLIC_KEY_SIZE,
               "GROUP_ID_LENGTH should be equal to CRYPTO_PUBLIC_KEY_SIZE");
 
+static const Group_c empty_group_c = {0};
+static const Group_Peer empty_group_peer = {{0}};
+
 non_null()
 static bool group_id_eq(const uint8_t *a, const uint8_t *b)
 {
@@ -116,8 +119,7 @@ static bool realloc_conferences(Group_Chats *g_c, uint16_t num)
 non_null()
 static void setup_conference(Group_c *g)
 {
-    memset(g, 0, sizeof(Group_c));
-
+    *g = empty_group_c;
     g->maxfrozen = MAX_FROZEN_DEFAULT;
 }
 
@@ -689,7 +691,7 @@ static int addpeer(Group_Chats *g_c, uint32_t groupnumber, const uint8_t *real_p
         return -1;
     }
 
-    memset(&temp[g->numpeers], 0, sizeof(Group_Peer));
+    temp[g->numpeers] = empty_group_peer;
     g->group = temp;
 
     const uint32_t new_index = g->numpeers;
@@ -3473,7 +3475,7 @@ static uint32_t load_group(Group_c *g, const Group_Chats *g_c, const uint8_t *da
         g->frozen = tmp_frozen;
 
         Group_Peer *peer = &g->frozen[j];
-        memset(peer, 0, sizeof(Group_Peer));
+        *peer = empty_group_peer;
 
         pk_copy(peer->real_pk, data);
         data += CRYPTO_PUBLIC_KEY_SIZE;

toxcore/network.c

@@ -340,6 +340,9 @@ static void fill_addr6(const IP6 *ip, struct in6_addr *addr)
 #define INADDR_LOOPBACK 0x7f000001
 #endif
 
+static const IP empty_ip = {{0}};
+static const IP_Port empty_ip_port = {{{0}}};
+
 const IP4 ip4_broadcast = { INADDR_BROADCAST };
 const IP6 ip6_broadcast = {
     { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }
@@ -1172,7 +1175,7 @@ void ip_reset(IP *ip)
         return;
     }
 
-    memset(ip, 0, sizeof(IP));
+    *ip = empty_ip;
 }
 
 /** nulls out ip_port */
@@ -1182,7 +1185,7 @@ void ipport_reset(IP_Port *ipport)
         return;
     }
 
-    memset(ipport, 0, sizeof(IP_Port));
+    *ipport = empty_ip_port;
 }
 
 /** nulls out ip, sets family according to flag */
@@ -1192,7 +1195,7 @@ void ip_init(IP *ip, bool ipv6enabled)
         return;
     }
 
-    memset(ip, 0, sizeof(IP));
+    *ip = empty_ip;
     ip->family = ipv6enabled ? net_family_ipv6 : net_family_ipv4;
 }
 

toxcore/onion_client.c

@@ -90,6 +90,8 @@ typedef struct Onion_Friend {
     uint32_t dht_pk_callback_number;
 } Onion_Friend;
 
+static const Onion_Friend empty_onion_friend = {false};
+
 typedef struct Onion_Data_Handler {
     oniondata_handler_cb *function;
     void *object;
@@ -287,9 +289,7 @@ static uint16_t random_nodes_path_onion(const Onion_Client *onion_c, Node_format
         }
 
         if (num_nodes >= 2) {
-            nodes[0] = (Node_format) {
-                0
-            };
+            nodes[0] = empty_node_format;
             nodes[0].ip_port.ip.family = net_family_tcp_family;
             nodes[0].ip_port.ip.ip.v4.uint32 = random_tcp;
 
@@ -304,9 +304,7 @@ static uint16_t random_nodes_path_onion(const Onion_Client *onion_c, Node_format
                 return 0;
             }
 
-            nodes[0] = (Node_format) {
-                0
-            };
+            nodes[0] = empty_node_format;
             nodes[0].ip_port.ip.family = net_family_tcp_family;
             nodes[0].ip_port.ip.ip.v4.uint32 = random_tcp;
 
@@ -1341,7 +1339,7 @@ int onion_addfriend(Onion_Client *onion_c, const uint8_t *public_key)
         }
 
         index = onion_c->num_friends;
-        memset(&onion_c->friends_list[onion_c->num_friends], 0, sizeof(Onion_Friend));
+        onion_c->friends_list[onion_c->num_friends] = empty_onion_friend;
         ++onion_c->num_friends;
     }