Pedantically use int32_t instead of int for max.

python · gpshead · Sep 4, 2022 · Sep 4, 2022 · Sep 5, 2022 · Sep 5, 2022
commit 67c9af4270ca11353f21e297b5c272503d28376a
@@ -79,6 +79,9 @@ PyAPI_FUNC(PyStatus) _PyArgv_AsWstrList(const _PyArgv *args,
 PyAPI_FUNC(int) _Py_str_to_int(
     const char *str,
     int *result);
+PyAPI_FUNC(int) _Py_str_to_int32(
+    const char *str,
+    int32_t *result);
 PyAPI_FUNC(const wchar_t*) _Py_get_xoption(
     const PyWideStringList *xoptions,
     const wchar_t *name);

@@ -176,7 +176,7 @@ struct _is {
     struct types_state types;
     struct callable_cache callable_cache;
 
-    int int_max_str_digits;
+    int32_t int_max_str_digits;
 
     /* The following fields are here to avoid allocation during init.
        The data is exposed through PyInterpreterState pointer fields.

diff --git a/Objects/longobject.c b/Objects/longobject.c
@@ -1767,7 +1767,7 @@ long_to_decimal_string_internal(PyObject *aa,
     if (size_a >= 10 * _PY_LONG_MAX_STR_DIGITS_THRESHOLD
                   / (3 * PyLong_SHIFT) + 2) {
         PyInterpreterState *interp = _PyInterpreterState_GET();
-        int max_str_digits = interp->int_max_str_digits;
+        int32_t max_str_digits = interp->int_max_str_digits;
         if ((max_str_digits > 0) &&
             (max_str_digits / (3 * PyLong_SHIFT) <= (size_a - 11) / 10)) {
             PyErr_Format(PyExc_ValueError, _MAX_STR_DIGITS_ERROR_FMT_TO_STR,
@@ -1837,7 +1837,7 @@ long_to_decimal_string_internal(PyObject *aa,
     }
     if (strlen > _PY_LONG_MAX_STR_DIGITS_THRESHOLD) {
         PyInterpreterState *interp = _PyInterpreterState_GET();
-        int max_str_digits = interp->int_max_str_digits;
+        int32_t max_str_digits = interp->int_max_str_digits;
         Py_ssize_t strlen_nosign = strlen - negative;
         if ((max_str_digits > 0) && (strlen_nosign > max_str_digits)) {
             Py_DECREF(scratch);
@@ -2514,7 +2514,7 @@ digit beyond the first.
         /* Limit the size to avoid excessive computation attacks. */
         if (digits > _PY_LONG_MAX_STR_DIGITS_THRESHOLD) {
             PyInterpreterState *interp = _PyInterpreterState_GET();
-            int max_str_digits = interp->int_max_str_digits;
+            int32_t max_str_digits = interp->int_max_str_digits;
             if ((max_str_digits > 0) && (digits > max_str_digits)) {
                 PyErr_Format(PyExc_ValueError, _MAX_STR_DIGITS_ERROR_FMT_TO_INT,
                              max_str_digits, digits);

diff --git a/Python/clinic/sysmodule.c.h b/Python/clinic/sysmodule.c.h
@@ -1630,6 +1630,28 @@ config_wstr_to_int(const wchar_t *wstr, int *result)
 }
 
 
+static int
+config_wstr_to_int32(const wchar_t *wstr, int32_t *result)
+{
+#if INT32_MAX == INT_MAX && INT32_MIN == INT_MIN
+    return config_wstr_to_int(wstr, result);
+#else
+    const wchar_t *endptr = wstr;
+    errno = 0;
+    long value = wcstol(wstr, (wchar_t **)&endptr, 10);
+    if (*endptr != '\0' || errno == ERANGE) {
+        return -1;
+    }
+    if (value < INT32_MIN || value > INT32_MAX) {
+        return -1;
+    }
+
+    *result = (int32_t)value;
+    return 0;
+#endif
+}
+
+
 static PyStatus
 config_read_env_vars(PyConfig *config)
 {
@@ -1778,15 +1800,15 @@ config_init_tracemalloc(PyConfig *config)
 static PyStatus
 config_init_int_max_str_digits(PyConfig *config)
 {
-    int maxdigits;
-    int valid = 0;
+    int32_t maxdigits;
+    bool valid = 0;
 
     /* default to unconfigured, _PyLong_InitTypes() does the rest */
     config->int_max_str_digits = -1;
 
     const char *env = config_get_env(config, "PYTHONINTMAXSTRDIGITS");
     if (env) {
-        if (!_Py_str_to_int(env, &maxdigits)) {
+        if (!_Py_str_to_int32(env, &maxdigits)) {
             valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD));
         }
         if (!valid) {
@@ -1804,7 +1826,7 @@ config_init_int_max_str_digits(PyConfig *config)
     if (xoption) {
         const wchar_t *sep = wcschr(xoption, L'=');
         if (sep) {
-            if (!config_wstr_to_int(sep + 1, &maxdigits)) {
+            if (!config_wstr_to_int32(sep + 1, &maxdigits)) {
                 valid = ((maxdigits == 0) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD));
             }
         }

@@ -559,6 +559,28 @@ _Py_str_to_int(const char *str, int *result)
 }
 
 
+int
+_Py_str_to_int32(const char *str, int32_t *result)
+{
+#if INT32_MAX == INT_MAX && INT32_MIN == INT_MIN
+    return _Py_str_to_int(str, result);
+#else
+    const char *endptr = str;
+    errno = 0;
+    long value = strtol(str, (char **)&endptr, 10);
+    if (*endptr != '\0' || errno == ERANGE) {
+        return -1;
+    }
+    if (value < INT32_MIN || value > INT32_MAX) {
+        return -1;
+    }
+
+    *result = (int32_t)value;
+    return 0;
+#endif
+}
+
+
 void
 _Py_get_env_flag(int use_environment, int *flag, const char *name)
 {

@@ -1684,23 +1684,27 @@ sys_get_int_max_str_digits_impl(PyObject *module)
 /*[clinic end generated code: output=0042f5e8ae0e8631 input=8dab13e2023e60d5]*/
 {
     PyInterpreterState *interp = _PyInterpreterState_GET();
-    return PyLong_FromSsize_t(interp->int_max_str_digits);
+    return PyLong_FromLong(interp->int_max_str_digits);
 }
 
 /*[clinic input]
 sys.set_int_max_str_digits
 
-    maxdigits: int
+    maxdigits: long
 
 Set the maximum string digits limit for non-binary int<->str conversions.
 [clinic start generated code]*/
 
 static PyObject *
-sys_set_int_max_str_digits_impl(PyObject *module, int maxdigits)
-/*[clinic end generated code: output=734d4c2511f2a56d input=d7e3f325db6910c5]*/
+sys_set_int_max_str_digits_impl(PyObject *module, long maxdigits)
+/*[clinic end generated code: output=40ea5d33a82c5c44 input=657c61a1822f6bcf]*/
 {
     PyThreadState *tstate = _PyThreadState_GET();
     if ((!maxdigits) || (maxdigits >= _PY_LONG_MAX_STR_DIGITS_THRESHOLD)) {
+        if (maxdigits > INT32_MAX) {
+            /* Silently cap to our range; already effectively unlimited. */
+            maxdigits = INT32_MAX;
+        }
         tstate->interp->int_max_str_digits = maxdigits;
         Py_RETURN_NONE;
     } else {