unix/modsocket: Use type-checking mp_obj_get_int.

MP_OBJ_SMALL_INT_VALUE would give erroneous results, such as assertion
failures in the coverage build and other oddities like:

    >>> s = socket.socket()
    >>> s.recv(3.14)
    MemoryError: memory allocation failed, allocating 4235896656 bytes

Signed-off-by: Jeff Epler <jepler@gmail.com>

Author: jepler

ports/unix/modsocket.c

@@ -280,11 +280,11 @@ static MP_DEFINE_CONST_FUN_OBJ_1(socket_accept_obj, socket_accept);
 // these would be thrown as exceptions.
 static mp_obj_t socket_recv(size_t n_args, const mp_obj_t *args) {
     mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
-    int sz = MP_OBJ_SMALL_INT_VALUE(args[1]);
+    int sz = mp_obj_get_int(args[1]);
     int flags = 0;
 
     if (n_args > 2) {
-        flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
+        flags = mp_obj_get_int(args[2]);
     }
 
     byte *buf = m_new(byte, sz);
@@ -298,11 +298,11 @@ static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_recv_obj, 2, 3, socket_recv);
 
 static mp_obj_t socket_recvfrom(size_t n_args, const mp_obj_t *args) {
     mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
-    int sz = MP_OBJ_SMALL_INT_VALUE(args[1]);
+    int sz = mp_obj_get_int(args[1]);
     int flags = 0;
 
     if (n_args > 2) {
-        flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
+        flags = mp_obj_get_int(args[2]);
     }
 
     struct sockaddr_storage addr;
@@ -331,7 +331,7 @@ static mp_obj_t socket_send(size_t n_args, const mp_obj_t *args) {
     int flags = 0;
 
     if (n_args > 2) {
-        flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
+        flags = mp_obj_get_int(args[2]);
     }
 
     mp_buffer_info_t bufinfo;
@@ -349,7 +349,7 @@ static mp_obj_t socket_sendto(size_t n_args, const mp_obj_t *args) {
 
     mp_obj_t dst_addr = args[2];
     if (n_args > 3) {
-        flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
+        flags = mp_obj_get_int(args[2]);
         dst_addr = args[3];
     }
 
@@ -366,7 +366,7 @@ static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_sendto_obj, 3, 4, socket_sendt
 static mp_obj_t socket_setsockopt(size_t n_args, const mp_obj_t *args) {
     (void)n_args; // always 4
     mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
-    int level = MP_OBJ_SMALL_INT_VALUE(args[1]);
+    int level = mp_obj_get_int(args[1]);
     int option = mp_obj_get_int(args[2]);
 
     const void *optval;
@@ -478,14 +478,11 @@ static mp_obj_t socket_make_new(const mp_obj_type_t *type_in, size_t n_args, siz
     int proto = 0;
 
     if (n_args > 0) {
-        assert(mp_obj_is_small_int(args[0]));
-        family = MP_OBJ_SMALL_INT_VALUE(args[0]);
+        family = mp_obj_get_int(args[0]);
         if (n_args > 1) {
-            assert(mp_obj_is_small_int(args[1]));
-            type = MP_OBJ_SMALL_INT_VALUE(args[1]);
+            type = mp_obj_get_int(args[1]);
             if (n_args > 2) {
-                assert(mp_obj_is_small_int(args[2]));
-                proto = MP_OBJ_SMALL_INT_VALUE(args[2]);
+                proto = mp_obj_get_int(args[2]);
             }
         }
     }
@@ -582,7 +579,7 @@ static mp_obj_t mod_socket_getaddrinfo(size_t n_args, const mp_obj_t *args) {
     // getaddrinfo accepts port in string notation, so however
     // it may seem stupid, we need to convert int to str
     if (mp_obj_is_small_int(args[1])) {
-        unsigned port = (unsigned short)MP_OBJ_SMALL_INT_VALUE(args[1]);
+        unsigned port = (unsigned short)mp_obj_get_int(args[1]);
         snprintf(buf, sizeof(buf), "%u", port);
         serv = buf;
         hints.ai_flags = AI_NUMERICSERV;
@@ -605,13 +602,13 @@ static mp_obj_t mod_socket_getaddrinfo(size_t n_args, const mp_obj_t *args) {
     }
 
     if (n_args > 2) {
-        hints.ai_family = MP_OBJ_SMALL_INT_VALUE(args[2]);
+        hints.ai_family = mp_obj_get_int(args[2]);
         if (n_args > 3) {
-            hints.ai_socktype = MP_OBJ_SMALL_INT_VALUE(args[3]);
+            hints.ai_socktype = mp_obj_get_int(args[3]);
             if (n_args > 4) {
-                hints.ai_protocol = MP_OBJ_SMALL_INT_VALUE(args[4]);
+                hints.ai_protocol = mp_obj_get_int(args[4]);
                 if (n_args > 5) {
-                    hints.ai_flags = MP_OBJ_SMALL_INT_VALUE(args[5]);
+                    hints.ai_flags = mp_obj_get_int(args[5]);
                 }
             }
         }

tests/extmod/socket_badconstructor.py

@@ -0,0 +1,22 @@
+# Test passing in bad values to socket.socket constructor.
+
+try:
+    import socket
+except:
+    print("SKIP")
+    raise SystemExit
+
+try:
+    s = socket.socket(None)
+except TypeError:
+    print("TypeError")
+
+try:
+    s = socket.socket(socket.AF_INET, None)
+except TypeError:
+    print("TypeError")
+
+try:
+    s = socket.socket(socket.AF_INET, socket.SOCK_RAW, None)
+except TypeError:
+    print("TypeError")