INT2STRING to use Stack based solution

Author: Rock Li

bson/_cbsonmodule.c

@@ -82,29 +82,23 @@ static struct module_state _state;
  * must be explicitly free'd when done being used.
  */
 #if defined(_MSC_VER) && (_MSC_VER >= 1400)
-#define INT2STRING(buffer, i) \
- *(buffer) = malloc(_scprintf("%d", (i)) + 1), \
- (!(buffer) ? \
- -1 : \
- _snprintf_s(*(buffer), \
- _scprintf("%d", (i)) + 1, \
- _scprintf("%d", (i)) + 1, \
- "%d", \
- (i)))
+#define INT2STRING(buffer, i) \
+ _snprintf_s((buffer), \
+ _scprintf("%d", (i)) + 1, \
+ _scprintf("%d", (i)) + 1, \
+ "%d", \
+ (i))
 #define STRCAT(dest, n, src) strcat_s((dest), (n), (src))
 #else
-#define INT2STRING(buffer, i) \
- *(buffer) = malloc(_scprintf("%d", (i)) + 1), \
- (!(buffer) ? \
- -1 : \
- _snprintf(*(buffer), \
- _scprintf("%d", (i)) + 1, \
- "%d", \
- (i)))
+#define INT2STRING(buffer, i) \
+ _snprintf((buffer), \
+ _scprintf("%d", (i)) + 1, \
+ "%d", \
+ (i))
 #define STRCAT(dest, n, src) strcat((dest), (src))
 #endif
 #else
-#define INT2STRING(buffer, i) asprintf((buffer), "%d", (i))
+#define INT2STRING(buffer, i) snprintf((buffer), sizeof((buffer)), "%d", (i))
 #define STRCAT(dest, n, src) strcat((dest), (src))
 #endif
 
@@ -464,22 +458,17 @@ static int _write_element_to_buffer(PyObject* self, buffer_t buffer, int type_by
  }
  for(i = 0; i < items; i++) {
  int list_type_byte = buffer_save_space(buffer, 1);
- char* name = NULL;
+ char name[16];
  PyObject* item_value;
 
  if (list_type_byte == -1) {
  PyErr_NoMemory();
  return 0;
  }
- if (INT2STRING(&name, (int)i) < 0 || !name) {
- PyErr_NoMemory();
- return 0;
- }
+ INT2STRING(name, (int)i);
  if (!buffer_write_bytes(buffer, name, (int)strlen(name) + 1)) {
- free(name);
  return 0;
  }
- free(name);
 
  if (!(item_value = PySequence_GetItem(value, i)))
  return 0;