gh-118201: Simplify conv_confname (#126089)

mhsmith · mhsmith · commit 9466eb81375e · 2025-03-17T18:30:17.000Z
(cherry picked from commit c5c9286)
diff --git a/Lib/test/support/os_helper.py b/Lib/test/support/os_helper.py
@@ -632,8 +632,7 @@ def fd_count():
     if hasattr(os, 'sysconf'):
         try:
             MAXFD = os.sysconf("SC_OPEN_MAX")
-        except (OSError, ValueError):
-            # gh-118201: ValueError is raised intermittently on iOS
+        except OSError:
             pass
 
     old_modes = None
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
@@ -2397,8 +2397,8 @@ def test_fchown(self):
         support.is_emscripten or support.is_wasi,
         "musl libc issue on Emscripten/WASI, bpo-46390"
     )
-    @unittest.skipIf(support.is_apple_mobile, "gh-118201: Test is flaky on iOS")
     def test_fpathconf(self):
+        self.assertIn("PC_NAME_MAX", os.pathconf_names)
         self.check(os.pathconf, "PC_NAME_MAX")
         self.check(os.fpathconf, "PC_NAME_MAX")
         self.check_bool(os.pathconf, "PC_NAME_MAX")
diff --git a/Lib/test/test_posix.py b/Lib/test/test_posix.py
@@ -568,10 +568,38 @@ def test_dup(self):
 
     @unittest.skipUnless(hasattr(posix, 'confstr'),
                          'test needs posix.confstr()')
-    @unittest.skipIf(support.is_apple_mobile, "gh-118201: Test is flaky on iOS")
     def test_confstr(self):
-        self.assertRaises(ValueError, posix.confstr, "CS_garbage")
-        self.assertEqual(len(posix.confstr("CS_PATH")) > 0, True)
+        with self.assertRaisesRegex(
+            ValueError, "unrecognized configuration name"
+        ):
+            posix.confstr("CS_garbage")
+
+        with self.assertRaisesRegex(
+            TypeError, "configuration names must be strings or integers"
+        ):
+            posix.confstr(1.23)
+
+        path = posix.confstr("CS_PATH")
+        self.assertGreater(len(path), 0)
+        self.assertEqual(posix.confstr(posix.confstr_names["CS_PATH"]), path)
+
+    @unittest.skipUnless(hasattr(posix, 'sysconf'),
+                         'test needs posix.sysconf()')
+    def test_sysconf(self):
+        with self.assertRaisesRegex(
+            ValueError, "unrecognized configuration name"
+        ):
+            posix.sysconf("SC_garbage")
+
+        with self.assertRaisesRegex(
+            TypeError, "configuration names must be strings or integers"
+        ):
+            posix.sysconf(1.23)
+
+        arg_max = posix.sysconf("SC_ARG_MAX")
+        self.assertGreater(arg_max, 0)
+        self.assertEqual(
+            posix.sysconf(posix.sysconf_names["SC_ARG_MAX"]), arg_max)
 
     @unittest.skipUnless(hasattr(posix, 'dup2'),
                          'test needs posix.dup2()')
diff --git a/Misc/NEWS.d/next/Library/2024-10-28-19-49-18.gh-issue-118201.v41XXh.rst b/Misc/NEWS.d/next/Library/2024-10-28-19-49-18.gh-issue-118201.v41XXh.rst
@@ -0,0 +1,2 @@
+Fixed intermittent failures of :any:`os.confstr`, :any:`os.pathconf` and
+:any:`os.sysconf` on iOS and Android.
diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
@@ -3078,18 +3078,22 @@ class Py_off_t_return_converter(long_return_converter):
     type = 'Py_off_t'
     conversion_fn = 'PyLong_FromPy_off_t'
 
-class path_confname_converter(CConverter):
+class confname_converter(CConverter):
     type="int"
-    converter="conv_path_confname"
+    converter="conv_confname"
 
-class confstr_confname_converter(path_confname_converter):
-    converter='conv_confstr_confname'
+    def converter_init(self, *, table):
+        self.table = table
 
-class sysconf_confname_converter(path_confname_converter):
-    converter="conv_sysconf_confname"
+    def parse_arg(self, argname, displayname, *, limited_capi):
+        return self.format_code("""
+            if (!{converter}(module, {argname}, &{paramname}, "{table}")) {{{{
+                goto exit;
+            }}}}
+        """, argname=argname, converter=self.converter, table=self.table)
 
 [python start generated code]*/
-/*[python end generated code: output=da39a3ee5e6b4b0d input=577cb476e5d64960]*/
+/*[python end generated code: output=da39a3ee5e6b4b0d input=a6199b1618d73f53]*/
 
 /*[clinic input]
 
@@ -13503,46 +13507,38 @@ struct constdef {
 };
 
 static int
-conv_confname(PyObject *arg, int *valuep, struct constdef *table,
-              size_t tablesize)
+conv_confname(PyObject *module, PyObject *arg, int *valuep, const char *tablename)
 {
-    if (PyLong_Check(arg)) {
-        int value = PyLong_AsInt(arg);
-        if (value == -1 && PyErr_Occurred())
-            return 0;
-        *valuep = value;
-        return 1;
-    }
-    else {
-        /* look up the value in the table using a binary search */
-        size_t lo = 0;
-        size_t mid;
-        size_t hi = tablesize;
-        int cmp;
-        const char *confname;
-        if (!PyUnicode_Check(arg)) {
-            PyErr_SetString(PyExc_TypeError,
-                "configuration names must be strings or integers");
+    if (PyUnicode_Check(arg)) {
+        PyObject *table = PyObject_GetAttrString(module, tablename);
+        if (table == NULL) {
             return 0;
         }
-        confname = PyUnicode_AsUTF8(arg);
-        if (confname == NULL)
+
+        arg = PyObject_GetItem(table, arg);
+        Py_DECREF(table);
+        if (arg == NULL) {
+            PyErr_SetString(
+                PyExc_ValueError, "unrecognized configuration name");
             return 0;
-        while (lo < hi) {
-            mid = (lo + hi) / 2;
-            cmp = strcmp(confname, table[mid].name);
-            if (cmp < 0)
-                hi = mid;
-            else if (cmp > 0)
-                lo = mid + 1;
-            else {
-                *valuep = table[mid].value;
-                return 1;
-            }
         }
-        PyErr_SetString(PyExc_ValueError, "unrecognized configuration name");
-        return 0;
+    } else {
+        Py_INCREF(arg);  // Match the Py_DECREF below.
+    }
+
+    int success = 0;
+    if (!PyLong_Check(arg)) {
+        PyErr_SetString(PyExc_TypeError,
+            "configuration names must be strings or integers");
+    } else {
+        int value = PyLong_AsInt(arg);
+        if (!(value == -1 && PyErr_Occurred())) {
+            *valuep = value;
+            success = 1;
+        }
     }
+    Py_DECREF(arg);
+    return success;
 }
 
 
@@ -13633,14 +13629,6 @@ static struct constdef  posix_constants_pathconf[] = {
     {"PC_TIMESTAMP_RESOLUTION", _PC_TIMESTAMP_RESOLUTION},
 #endif
 };
-
-static int
-conv_path_confname(PyObject *arg, int *valuep)
-{
-    return conv_confname(arg, valuep, posix_constants_pathconf,
-                         sizeof(posix_constants_pathconf)
-                           / sizeof(struct constdef));
-}
 #endif
 
 
@@ -13649,7 +13637,7 @@ conv_path_confname(PyObject *arg, int *valuep)
 os.fpathconf -> long
 
     fd: fildes
-    name: path_confname
+    name: confname(table="pathconf_names")
     /
 
 Return the configuration limit name for the file descriptor fd.
@@ -13659,7 +13647,7 @@ If there is no limit, return -1.
 
 static long
 os_fpathconf_impl(PyObject *module, int fd, int name)
-/*[clinic end generated code: output=d5b7042425fc3e21 input=5b8d2471cfaae186]*/
+/*[clinic end generated code: output=d5b7042425fc3e21 input=023d44589c9ed6aa]*/
 {
     long limit;
 
@@ -13677,7 +13665,7 @@ os_fpathconf_impl(PyObject *module, int fd, int name)
 /*[clinic input]
 os.pathconf -> long
     path: path_t(allow_fd='PATH_HAVE_FPATHCONF')
-    name: path_confname
+    name: confname(table="pathconf_names")
 
 Return the configuration limit name for the file or directory path.
 
@@ -13688,7 +13676,7 @@ On some platforms, path may also be specified as an open file descriptor.
 
 static long
 os_pathconf_impl(PyObject *module, path_t *path, int name)
-/*[clinic end generated code: output=5bedee35b293a089 input=bc3e2a985af27e5e]*/
+/*[clinic end generated code: output=5bedee35b293a089 input=6f6072f57b10c787]*/
 {
     long limit;
 
@@ -13865,27 +13853,19 @@ static struct constdef posix_constants_confstr[] = {
 #endif
 };
 
-static int
-conv_confstr_confname(PyObject *arg, int *valuep)
-{
-    return conv_confname(arg, valuep, posix_constants_confstr,
-                         sizeof(posix_constants_confstr)
-                           / sizeof(struct constdef));
-}
-
 
 /*[clinic input]
 os.confstr
 
-    name: confstr_confname
+    name: confname(table="confstr_names")
     /
 
 Return a string-valued system configuration variable.
 [clinic start generated code]*/
 
 static PyObject *
 os_confstr_impl(PyObject *module, int name)
-/*[clinic end generated code: output=bfb0b1b1e49b9383 input=18fb4d0567242e65]*/
+/*[clinic end generated code: output=bfb0b1b1e49b9383 input=4c6ffca2837ec959]*/
 {
     PyObject *result = NULL;
     char buffer[255];
@@ -14422,26 +14402,18 @@ static struct constdef posix_constants_sysconf[] = {
 #endif
 };
 
-static int
-conv_sysconf_confname(PyObject *arg, int *valuep)
-{
-    return conv_confname(arg, valuep, posix_constants_sysconf,
-                         sizeof(posix_constants_sysconf)
-                           / sizeof(struct constdef));
-}
-
 
 /*[clinic input]
 os.sysconf -> long
-    name: sysconf_confname
+    name: confname(table="sysconf_names")
     /
 
 Return an integer-valued system configuration variable.
 [clinic start generated code]*/
 
 static long
 os_sysconf_impl(PyObject *module, int name)
-/*[clinic end generated code: output=3662f945fc0cc756 input=279e3430a33f29e4]*/
+/*[clinic end generated code: output=3662f945fc0cc756 input=930b8f23b5d15086]*/
 {
     long value;
 
@@ -14454,40 +14426,15 @@ os_sysconf_impl(PyObject *module, int name)
 #endif /* HAVE_SYSCONF */
 
 
-/* This code is used to ensure that the tables of configuration value names
- * are in sorted order as required by conv_confname(), and also to build
- * the exported dictionaries that are used to publish information about the
- * names available on the host platform.
- *
- * Sorting the table at runtime ensures that the table is properly ordered
- * when used, even for platforms we're not able to test on.  It also makes
- * it easier to add additional entries to the tables.
- */
-
-static int
-cmp_constdefs(const void *v1,  const void *v2)
-{
-    const struct constdef *c1 =
-    (const struct constdef *) v1;
-    const struct constdef *c2 =
-    (const struct constdef *) v2;
-
-    return strcmp(c1->name, c2->name);
-}
-
 static int
 setup_confname_table(struct constdef *table, size_t tablesize,
                      const char *tablename, PyObject *module)
 {
-    PyObject *d = NULL;
-    size_t i;
-
-    qsort(table, tablesize, sizeof(struct constdef), cmp_constdefs);
-    d = PyDict_New();
+    PyObject *d = PyDict_New();
     if (d == NULL)
         return -1;
 
-    for (i=0; i < tablesize; ++i) {
+    for (size_t i=0; i < tablesize; ++i) {
         PyObject *o = PyLong_FromLong(table[i].value);
         if (o == NULL || PyDict_SetItemString(d, table[i].name, o) == -1) {
             Py_XDECREF(o);

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Fixed intermittent failures of :any:`os.confstr`, :any:`os.pathconf` and
	`2`	+:any:`os.sysconf` on iOS and Android.