1 /*
2  * C Extension module to test Python internal C APIs (Include/internal).
3  */
4 
5 #ifndef Py_BUILD_CORE_BUILTIN
6 #  define Py_BUILD_CORE_MODULE 1
7 #endif
8 
9 /* Always enable assertions */
10 #undef NDEBUG
11 
12 #define PY_SSIZE_T_CLEAN
13 
14 #include "Python.h"
15 #include "pycore_atomic_funcs.h" // _Py_atomic_int_get()
16 #include "pycore_bitutils.h"     // _Py_bswap32()
17 #include "pycore_fileutils.h"    // _Py_normpath
18 #include "pycore_frame.h"        // _PyInterpreterFrame
19 #include "pycore_gc.h"           // PyGC_Head
20 #include "pycore_hashtable.h"    // _Py_hashtable_new()
21 #include "pycore_initconfig.h"   // _Py_GetConfigsAsDict()
22 #include "pycore_pathconfig.h"   // _PyPathConfig_ClearGlobal()
23 #include "pycore_interp.h"       // _PyInterpreterState_GetConfigCopy()
24 #include "pycore_pyerrors.h"     // _Py_UTF8_Edit_Cost()
25 #include "pycore_pystate.h"      // _PyThreadState_GET()
26 #include "osdefs.h"              // MAXPATHLEN
27 
28 
29 static PyObject *
get_configs(PyObject * self,PyObject * Py_UNUSED (args))30 get_configs(PyObject *self, PyObject *Py_UNUSED(args))
31 {
32     return _Py_GetConfigsAsDict();
33 }
34 
35 
36 static PyObject*
get_recursion_depth(PyObject * self,PyObject * Py_UNUSED (args))37 get_recursion_depth(PyObject *self, PyObject *Py_UNUSED(args))
38 {
39     PyThreadState *tstate = _PyThreadState_GET();
40 
41     /* subtract one to ignore the frame of the get_recursion_depth() call */
42 
43     return PyLong_FromLong(tstate->recursion_limit - tstate->recursion_remaining - 1);
44 }
45 
46 
47 static PyObject*
test_bswap(PyObject * self,PyObject * Py_UNUSED (args))48 test_bswap(PyObject *self, PyObject *Py_UNUSED(args))
49 {
50     uint16_t u16 = _Py_bswap16(UINT16_C(0x3412));
51     if (u16 != UINT16_C(0x1234)) {
52         PyErr_Format(PyExc_AssertionError,
53                      "_Py_bswap16(0x3412) returns %u", u16);
54         return NULL;
55     }
56 
57     uint32_t u32 = _Py_bswap32(UINT32_C(0x78563412));
58     if (u32 != UINT32_C(0x12345678)) {
59         PyErr_Format(PyExc_AssertionError,
60                      "_Py_bswap32(0x78563412) returns %lu", u32);
61         return NULL;
62     }
63 
64     uint64_t u64 = _Py_bswap64(UINT64_C(0xEFCDAB9078563412));
65     if (u64 != UINT64_C(0x1234567890ABCDEF)) {
66         PyErr_Format(PyExc_AssertionError,
67                      "_Py_bswap64(0xEFCDAB9078563412) returns %llu", u64);
68         return NULL;
69     }
70 
71     Py_RETURN_NONE;
72 }
73 
74 
75 static int
check_popcount(uint32_t x,int expected)76 check_popcount(uint32_t x, int expected)
77 {
78     // Use volatile to prevent the compiler to optimize out the whole test
79     volatile uint32_t u = x;
80     int bits = _Py_popcount32(u);
81     if (bits != expected) {
82         PyErr_Format(PyExc_AssertionError,
83                      "_Py_popcount32(%lu) returns %i, expected %i",
84                      (unsigned long)x, bits, expected);
85         return -1;
86     }
87     return 0;
88 }
89 
90 
91 static PyObject*
test_popcount(PyObject * self,PyObject * Py_UNUSED (args))92 test_popcount(PyObject *self, PyObject *Py_UNUSED(args))
93 {
94 #define CHECK(X, RESULT) \
95     do { \
96         if (check_popcount(X, RESULT) < 0) { \
97             return NULL; \
98         } \
99     } while (0)
100 
101     CHECK(0, 0);
102     CHECK(1, 1);
103     CHECK(0x08080808, 4);
104     CHECK(0x10000001, 2);
105     CHECK(0x10101010, 4);
106     CHECK(0x10204080, 4);
107     CHECK(0xDEADCAFE, 22);
108     CHECK(0xFFFFFFFF, 32);
109     Py_RETURN_NONE;
110 
111 #undef CHECK
112 }
113 
114 
115 static int
check_bit_length(unsigned long x,int expected)116 check_bit_length(unsigned long x, int expected)
117 {
118     // Use volatile to prevent the compiler to optimize out the whole test
119     volatile unsigned long u = x;
120     int len = _Py_bit_length(u);
121     if (len != expected) {
122         PyErr_Format(PyExc_AssertionError,
123                      "_Py_bit_length(%lu) returns %i, expected %i",
124                      x, len, expected);
125         return -1;
126     }
127     return 0;
128 }
129 
130 
131 static PyObject*
test_bit_length(PyObject * self,PyObject * Py_UNUSED (args))132 test_bit_length(PyObject *self, PyObject *Py_UNUSED(args))
133 {
134 #define CHECK(X, RESULT) \
135     do { \
136         if (check_bit_length(X, RESULT) < 0) { \
137             return NULL; \
138         } \
139     } while (0)
140 
141     CHECK(0, 0);
142     CHECK(1, 1);
143     CHECK(0x1000, 13);
144     CHECK(0x1234, 13);
145     CHECK(0x54321, 19);
146     CHECK(0x7FFFFFFF, 31);
147     CHECK(0xFFFFFFFF, 32);
148     Py_RETURN_NONE;
149 
150 #undef CHECK
151 }
152 
153 
154 #define TO_PTR(ch) ((void*)(uintptr_t)ch)
155 #define FROM_PTR(ptr) ((uintptr_t)ptr)
156 #define VALUE(key) (1 + ((int)(key) - 'a'))
157 
158 static Py_uhash_t
hash_char(const void * key)159 hash_char(const void *key)
160 {
161     char ch = (char)FROM_PTR(key);
162     return ch;
163 }
164 
165 
166 static int
hashtable_cb(_Py_hashtable_t * table,const void * key_ptr,const void * value_ptr,void * user_data)167 hashtable_cb(_Py_hashtable_t *table,
168              const void *key_ptr, const void *value_ptr,
169              void *user_data)
170 {
171     int *count = (int *)user_data;
172     char key = (char)FROM_PTR(key_ptr);
173     int value = (int)FROM_PTR(value_ptr);
174     assert(value == VALUE(key));
175     *count += 1;
176     return 0;
177 }
178 
179 
180 static PyObject*
test_hashtable(PyObject * self,PyObject * Py_UNUSED (args))181 test_hashtable(PyObject *self, PyObject *Py_UNUSED(args))
182 {
183     _Py_hashtable_t *table = _Py_hashtable_new(hash_char,
184                                                _Py_hashtable_compare_direct);
185     if (table == NULL) {
186         return PyErr_NoMemory();
187     }
188 
189     // Using an newly allocated table must not crash
190     assert(table->nentries == 0);
191     assert(table->nbuckets > 0);
192     assert(_Py_hashtable_get(table, TO_PTR('x')) == NULL);
193 
194     // Test _Py_hashtable_set()
195     char key;
196     for (key='a'; key <= 'z'; key++) {
197         int value = VALUE(key);
198         if (_Py_hashtable_set(table, TO_PTR(key), TO_PTR(value)) < 0) {
199             _Py_hashtable_destroy(table);
200             return PyErr_NoMemory();
201         }
202     }
203     assert(table->nentries == 26);
204     assert(table->nbuckets > table->nentries);
205 
206     // Test _Py_hashtable_get_entry()
207     for (key='a'; key <= 'z'; key++) {
208         _Py_hashtable_entry_t *entry = _Py_hashtable_get_entry(table, TO_PTR(key));
209         assert(entry != NULL);
210         assert(entry->key == TO_PTR(key));
211         assert(entry->value == TO_PTR(VALUE(key)));
212     }
213 
214     // Test _Py_hashtable_get()
215     for (key='a'; key <= 'z'; key++) {
216         void *value_ptr = _Py_hashtable_get(table, TO_PTR(key));
217         assert((int)FROM_PTR(value_ptr) == VALUE(key));
218     }
219 
220     // Test _Py_hashtable_steal()
221     key = 'p';
222     void *value_ptr = _Py_hashtable_steal(table, TO_PTR(key));
223     assert((int)FROM_PTR(value_ptr) == VALUE(key));
224     assert(table->nentries == 25);
225     assert(_Py_hashtable_get_entry(table, TO_PTR(key)) == NULL);
226 
227     // Test _Py_hashtable_foreach()
228     int count = 0;
229     int res = _Py_hashtable_foreach(table, hashtable_cb, &count);
230     assert(res == 0);
231     assert(count == 25);
232 
233     // Test _Py_hashtable_clear()
234     _Py_hashtable_clear(table);
235     assert(table->nentries == 0);
236     assert(table->nbuckets > 0);
237     assert(_Py_hashtable_get(table, TO_PTR('x')) == NULL);
238 
239     _Py_hashtable_destroy(table);
240     Py_RETURN_NONE;
241 }
242 
243 
244 static PyObject *
test_get_config(PyObject * Py_UNUSED (self),PyObject * Py_UNUSED (args))245 test_get_config(PyObject *Py_UNUSED(self), PyObject *Py_UNUSED(args))
246 {
247     PyConfig config;
248     PyConfig_InitIsolatedConfig(&config);
249     if (_PyInterpreterState_GetConfigCopy(&config) < 0) {
250         PyConfig_Clear(&config);
251         return NULL;
252     }
253     PyObject *dict = _PyConfig_AsDict(&config);
254     PyConfig_Clear(&config);
255     return dict;
256 }
257 
258 
259 static PyObject *
test_set_config(PyObject * Py_UNUSED (self),PyObject * dict)260 test_set_config(PyObject *Py_UNUSED(self), PyObject *dict)
261 {
262     PyConfig config;
263     PyConfig_InitIsolatedConfig(&config);
264     if (_PyConfig_FromDict(&config, dict) < 0) {
265         goto error;
266     }
267     if (_PyInterpreterState_SetConfig(&config) < 0) {
268         goto error;
269     }
270     PyConfig_Clear(&config);
271     Py_RETURN_NONE;
272 
273 error:
274     PyConfig_Clear(&config);
275     return NULL;
276 }
277 
278 
279 static PyObject *
test_reset_path_config(PyObject * Py_UNUSED (self),PyObject * Py_UNUSED (arg))280 test_reset_path_config(PyObject *Py_UNUSED(self), PyObject *Py_UNUSED(arg))
281 {
282     _PyPathConfig_ClearGlobal();
283     Py_RETURN_NONE;
284 }
285 
286 
287 static PyObject*
test_atomic_funcs(PyObject * self,PyObject * Py_UNUSED (args))288 test_atomic_funcs(PyObject *self, PyObject *Py_UNUSED(args))
289 {
290     // Test _Py_atomic_size_get() and _Py_atomic_size_set()
291     Py_ssize_t var = 1;
292     _Py_atomic_size_set(&var, 2);
293     assert(_Py_atomic_size_get(&var) == 2);
294     Py_RETURN_NONE;
295 }
296 
297 
298 static int
check_edit_cost(const char * a,const char * b,Py_ssize_t expected)299 check_edit_cost(const char *a, const char *b, Py_ssize_t expected)
300 {
301     int ret = -1;
302     PyObject *a_obj = NULL;
303     PyObject *b_obj = NULL;
304 
305     a_obj = PyUnicode_FromString(a);
306     if (a_obj == NULL) {
307         goto exit;
308     }
309     b_obj = PyUnicode_FromString(b);
310     if (b_obj == NULL) {
311         goto exit;
312     }
313     Py_ssize_t result = _Py_UTF8_Edit_Cost(a_obj, b_obj, -1);
314     if (result != expected) {
315         PyErr_Format(PyExc_AssertionError,
316                      "Edit cost from '%s' to '%s' returns %zd, expected %zd",
317                      a, b, result, expected);
318         goto exit;
319     }
320     // Check that smaller max_edits thresholds are exceeded.
321     Py_ssize_t max_edits = result;
322     while (max_edits > 0) {
323         max_edits /= 2;
324         Py_ssize_t result2 = _Py_UTF8_Edit_Cost(a_obj, b_obj, max_edits);
325         if (result2 <= max_edits) {
326             PyErr_Format(PyExc_AssertionError,
327                          "Edit cost from '%s' to '%s' (threshold %zd) "
328                          "returns %zd, expected greater than %zd",
329                          a, b, max_edits, result2, max_edits);
330             goto exit;
331         }
332     }
333     // Check that bigger max_edits thresholds don't change anything
334     Py_ssize_t result3 = _Py_UTF8_Edit_Cost(a_obj, b_obj, result * 2 + 1);
335     if (result3 != result) {
336         PyErr_Format(PyExc_AssertionError,
337                      "Edit cost from '%s' to '%s' (threshold %zd) "
338                      "returns %zd, expected %zd",
339                      a, b, result * 2, result3, result);
340         goto exit;
341     }
342     ret = 0;
343 exit:
344     Py_XDECREF(a_obj);
345     Py_XDECREF(b_obj);
346     return ret;
347 }
348 
349 static PyObject *
test_edit_cost(PyObject * self,PyObject * Py_UNUSED (args))350 test_edit_cost(PyObject *self, PyObject *Py_UNUSED(args))
351 {
352     #define CHECK(a, b, n) do {              \
353         if (check_edit_cost(a, b, n) < 0) {  \
354             return NULL;                     \
355         }                                    \
356     } while (0)                              \
357 
358     CHECK("", "", 0);
359     CHECK("", "a", 2);
360     CHECK("a", "A", 1);
361     CHECK("Apple", "Aple", 2);
362     CHECK("Banana", "B@n@n@", 6);
363     CHECK("Cherry", "Cherry!", 2);
364     CHECK("---0---", "------", 2);
365     CHECK("abc", "y", 6);
366     CHECK("aa", "bb", 4);
367     CHECK("aaaaa", "AAAAA", 5);
368     CHECK("wxyz", "wXyZ", 2);
369     CHECK("wxyz", "wXyZ123", 8);
370     CHECK("Python", "Java", 12);
371     CHECK("Java", "C#", 8);
372     CHECK("AbstractFoobarManager", "abstract_foobar_manager", 3+2*2);
373     CHECK("CPython", "PyPy", 10);
374     CHECK("CPython", "pypy", 11);
375     CHECK("AttributeError", "AttributeErrop", 2);
376     CHECK("AttributeError", "AttributeErrorTests", 10);
377 
378     #undef CHECK
379     Py_RETURN_NONE;
380 }
381 
382 
383 static PyObject *
normalize_path(PyObject * self,PyObject * filename)384 normalize_path(PyObject *self, PyObject *filename)
385 {
386     Py_ssize_t size = -1;
387     wchar_t *encoded = PyUnicode_AsWideCharString(filename, &size);
388     if (encoded == NULL) {
389         return NULL;
390     }
391 
392     PyObject *result = PyUnicode_FromWideChar(_Py_normpath(encoded, size), -1);
393     PyMem_Free(encoded);
394 
395     return result;
396 }
397 
398 static PyObject *
get_getpath_codeobject(PyObject * self,PyObject * Py_UNUSED (args))399 get_getpath_codeobject(PyObject *self, PyObject *Py_UNUSED(args)) {
400     return _Py_Get_Getpath_CodeObject();
401 }
402 
403 
404 static PyObject *
encode_locale_ex(PyObject * self,PyObject * args)405 encode_locale_ex(PyObject *self, PyObject *args)
406 {
407     PyObject *unicode;
408     int current_locale = 0;
409     wchar_t *wstr;
410     PyObject *res = NULL;
411     const char *errors = NULL;
412 
413     if (!PyArg_ParseTuple(args, "U|is", &unicode, &current_locale, &errors)) {
414         return NULL;
415     }
416     wstr = PyUnicode_AsWideCharString(unicode, NULL);
417     if (wstr == NULL) {
418         return NULL;
419     }
420     _Py_error_handler error_handler = _Py_GetErrorHandler(errors);
421 
422     char *str = NULL;
423     size_t error_pos;
424     const char *reason = NULL;
425     int ret = _Py_EncodeLocaleEx(wstr,
426                                  &str, &error_pos, &reason,
427                                  current_locale, error_handler);
428     PyMem_Free(wstr);
429 
430     switch(ret) {
431     case 0:
432         res = PyBytes_FromString(str);
433         PyMem_RawFree(str);
434         break;
435     case -1:
436         PyErr_NoMemory();
437         break;
438     case -2:
439         PyErr_Format(PyExc_RuntimeError, "encode error: pos=%zu, reason=%s",
440                      error_pos, reason);
441         break;
442     case -3:
443         PyErr_SetString(PyExc_ValueError, "unsupported error handler");
444         break;
445     default:
446         PyErr_SetString(PyExc_ValueError, "unknown error code");
447         break;
448     }
449     return res;
450 }
451 
452 
453 static PyObject *
decode_locale_ex(PyObject * self,PyObject * args)454 decode_locale_ex(PyObject *self, PyObject *args)
455 {
456     char *str;
457     int current_locale = 0;
458     PyObject *res = NULL;
459     const char *errors = NULL;
460 
461     if (!PyArg_ParseTuple(args, "y|is", &str, &current_locale, &errors)) {
462         return NULL;
463     }
464     _Py_error_handler error_handler = _Py_GetErrorHandler(errors);
465 
466     wchar_t *wstr = NULL;
467     size_t wlen = 0;
468     const char *reason = NULL;
469     int ret = _Py_DecodeLocaleEx(str,
470                                  &wstr, &wlen, &reason,
471                                  current_locale, error_handler);
472 
473     switch(ret) {
474     case 0:
475         res = PyUnicode_FromWideChar(wstr, wlen);
476         PyMem_RawFree(wstr);
477         break;
478     case -1:
479         PyErr_NoMemory();
480         break;
481     case -2:
482         PyErr_Format(PyExc_RuntimeError, "decode error: pos=%zu, reason=%s",
483                      wlen, reason);
484         break;
485     case -3:
486         PyErr_SetString(PyExc_ValueError, "unsupported error handler");
487         break;
488     default:
489         PyErr_SetString(PyExc_ValueError, "unknown error code");
490         break;
491     }
492     return res;
493 }
494 
495 static PyObject *record_list = NULL;
496 
497 static PyObject *
set_eval_frame_default(PyObject * self,PyObject * Py_UNUSED (args))498 set_eval_frame_default(PyObject *self, PyObject *Py_UNUSED(args))
499 {
500     _PyInterpreterState_SetEvalFrameFunc(PyInterpreterState_Get(), _PyEval_EvalFrameDefault);
501     Py_CLEAR(record_list);
502     Py_RETURN_NONE;
503 }
504 
505 static PyObject *
record_eval(PyThreadState * tstate,struct _PyInterpreterFrame * f,int exc)506 record_eval(PyThreadState *tstate, struct _PyInterpreterFrame *f, int exc)
507 {
508     PyList_Append(record_list, f->f_func->func_name);
509     return _PyEval_EvalFrameDefault(tstate, f, exc);
510 }
511 
512 
513 static PyObject *
set_eval_frame_record(PyObject * self,PyObject * list)514 set_eval_frame_record(PyObject *self, PyObject *list)
515 {
516     if (!PyList_Check(list)) {
517         PyErr_SetString(PyExc_TypeError, "argument must be a list");
518         return NULL;
519     }
520     Py_CLEAR(record_list);
521     Py_INCREF(list);
522     record_list = list;
523     _PyInterpreterState_SetEvalFrameFunc(PyInterpreterState_Get(), record_eval);
524     Py_RETURN_NONE;
525 }
526 
527 
528 static PyMethodDef TestMethods[] = {
529     {"get_configs", get_configs, METH_NOARGS},
530     {"get_recursion_depth", get_recursion_depth, METH_NOARGS},
531     {"test_bswap", test_bswap, METH_NOARGS},
532     {"test_popcount", test_popcount, METH_NOARGS},
533     {"test_bit_length", test_bit_length, METH_NOARGS},
534     {"test_hashtable", test_hashtable, METH_NOARGS},
535     {"get_config", test_get_config, METH_NOARGS},
536     {"set_config", test_set_config, METH_O},
537     {"reset_path_config", test_reset_path_config, METH_NOARGS},
538     {"test_atomic_funcs", test_atomic_funcs, METH_NOARGS},
539     {"test_edit_cost", test_edit_cost, METH_NOARGS},
540     {"normalize_path", normalize_path, METH_O, NULL},
541     {"get_getpath_codeobject", get_getpath_codeobject, METH_NOARGS, NULL},
542     {"EncodeLocaleEx", encode_locale_ex, METH_VARARGS},
543     {"DecodeLocaleEx", decode_locale_ex, METH_VARARGS},
544     {"set_eval_frame_default", set_eval_frame_default, METH_NOARGS, NULL},
545     {"set_eval_frame_record", set_eval_frame_record, METH_O, NULL},
546     {NULL, NULL} /* sentinel */
547 };
548 
549 
550 static struct PyModuleDef _testcapimodule = {
551     PyModuleDef_HEAD_INIT,
552     "_testinternalcapi",
553     NULL,
554     -1,
555     TestMethods,
556     NULL,
557     NULL,
558     NULL,
559     NULL
560 };
561 
562 
563 PyMODINIT_FUNC
PyInit__testinternalcapi(void)564 PyInit__testinternalcapi(void)
565 {
566     PyObject *module = PyModule_Create(&_testcapimodule);
567     if (module == NULL) {
568         return NULL;
569     }
570 
571     if (PyModule_AddObject(module, "SIZEOF_PYGC_HEAD",
572                            PyLong_FromSsize_t(sizeof(PyGC_Head))) < 0) {
573         goto error;
574     }
575 
576     return module;
577 
578 error:
579     Py_DECREF(module);
580     return NULL;
581 }
582