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1 /* parsermodule.c
2 *
3 * Copyright 1995-1996 by Fred L. Drake, Jr. and Virginia Polytechnic
4 * Institute and State University, Blacksburg, Virginia, USA.
5 * Portions copyright 1991-1995 by Stichting Mathematisch Centrum,
6 * Amsterdam, The Netherlands. Copying is permitted under the terms
7 * associated with the main Python distribution, with the additional
8 * restriction that this additional notice be included and maintained
9 * on all distributed copies.
10 *
11 * This module serves to replace the original parser module written
12 * by Guido. The functionality is not matched precisely, but the
13 * original may be implemented on top of this. This is desirable
14 * since the source of the text to be parsed is now divorced from
15 * this interface.
16 *
17 * Unlike the prior interface, the ability to give a parse tree
18 * produced by Python code as a tuple to the compiler is enabled by
19 * this module. See the documentation for more details.
20 *
21 * I've added some annotations that help with the lint code-checking
22 * program, but they're not complete by a long shot. The real errors
23 * that lint detects are gone, but there are still warnings with
24 * Py_[X]DECREF() and Py_[X]INCREF() macros. The lint annotations
25 * look like "NOTE(...)".
26 */
27
28 #include "Python.h" /* general Python API */
29 #include "Python-ast.h" /* mod_ty */
30 #include "graminit.h" /* symbols defined in the grammar */
31 #include "node.h" /* internal parser structure */
32 #include "errcode.h" /* error codes for PyNode_*() */
33 #include "token.h" /* token definitions */
34 #include "grammar.h"
35 #include "parsetok.h"
36 /* ISTERMINAL() / ISNONTERMINAL() */
37 #include "compile.h"
38 #undef Yield
39 #include "ast.h"
40 #include "pyarena.h"
41
42 extern grammar _PyParser_Grammar; /* From graminit.c */
43
44 #ifdef lint
45 #include <note.h>
46 #else
47 #define NOTE(x)
48 #endif
49
50 /* String constants used to initialize module attributes.
51 *
52 */
53 static char parser_copyright_string[] =
54 "Copyright 1995-1996 by Virginia Polytechnic Institute & State\n\
55 University, Blacksburg, Virginia, USA, and Fred L. Drake, Jr., Reston,\n\
56 Virginia, USA. Portions copyright 1991-1995 by Stichting Mathematisch\n\
57 Centrum, Amsterdam, The Netherlands.";
58
59
60 PyDoc_STRVAR(parser_doc_string,
61 "This is an interface to Python's internal parser.");
62
63 static char parser_version_string[] = "0.5";
64
65
66 typedef PyObject* (*SeqMaker) (Py_ssize_t length);
67 typedef int (*SeqInserter) (PyObject* sequence,
68 Py_ssize_t index,
69 PyObject* element);
70
71 /* The function below is copyrighted by Stichting Mathematisch Centrum. The
72 * original copyright statement is included below, and continues to apply
73 * in full to the function immediately following. All other material is
74 * original, copyrighted by Fred L. Drake, Jr. and Virginia Polytechnic
75 * Institute and State University. Changes were made to comply with the
76 * new naming conventions. Added arguments to provide support for creating
77 * lists as well as tuples, and optionally including the line numbers.
78 */
79
80
81 static PyObject*
82 node2tuple(node *n, /* node to convert */
83 SeqMaker mkseq, /* create sequence */
84 SeqInserter addelem, /* func. to add elem. in seq. */
85 int lineno, /* include line numbers? */
86 int col_offset) /* include column offsets? */
87 {
88 if (n == NULL) {
89 Py_INCREF(Py_None);
90 return (Py_None);
91 }
92 if (ISNONTERMINAL(TYPE(n))) {
93 int i;
94 PyObject *v;
95 PyObject *w;
96
97 v = mkseq(1 + NCH(n) + (TYPE(n) == encoding_decl));
98 if (v == NULL)
99 return (v);
100 w = PyInt_FromLong(TYPE(n));
101 if (w == NULL) {
102 Py_DECREF(v);
103 return ((PyObject*) NULL);
104 }
105 (void) addelem(v, 0, w);
106 for (i = 0; i < NCH(n); i++) {
107 w = node2tuple(CHILD(n, i), mkseq, addelem, lineno, col_offset);
108 if (w == NULL) {
109 Py_DECREF(v);
110 return ((PyObject*) NULL);
111 }
112 (void) addelem(v, i+1, w);
113 }
114
115 if (TYPE(n) == encoding_decl)
116 (void) addelem(v, i+1, PyString_FromString(STR(n)));
117 return (v);
118 }
119 else if (ISTERMINAL(TYPE(n))) {
120 PyObject *result = mkseq(2 + lineno + col_offset);
121 if (result != NULL) {
122 (void) addelem(result, 0, PyInt_FromLong(TYPE(n)));
123 (void) addelem(result, 1, PyString_FromString(STR(n)));
124 if (lineno == 1)
125 (void) addelem(result, 2, PyInt_FromLong(n->n_lineno));
126 if (col_offset == 1)
127 (void) addelem(result, 3, PyInt_FromLong(n->n_col_offset));
128 }
129 return (result);
130 }
131 else {
132 PyErr_SetString(PyExc_SystemError,
133 "unrecognized parse tree node type");
134 return ((PyObject*) NULL);
135 }
136 }
137 /*
138 * End of material copyrighted by Stichting Mathematisch Centrum.
139 */
140
141
142
143 /* There are two types of intermediate objects we're interested in:
144 * 'eval' and 'exec' types. These constants can be used in the st_type
145 * field of the object type to identify which any given object represents.
146 * These should probably go in an external header to allow other extensions
147 * to use them, but then, we really should be using C++ too. ;-)
148 */
149
150 #define PyST_EXPR 1
151 #define PyST_SUITE 2
152
153
154 /* These are the internal objects and definitions required to implement the
155 * ST type. Most of the internal names are more reminiscent of the 'old'
156 * naming style, but the code uses the new naming convention.
157 */
158
159 static PyObject*
160 parser_error = 0;
161
162
163 typedef struct {
164 PyObject_HEAD /* standard object header */
165 node* st_node; /* the node* returned by the parser */
166 int st_type; /* EXPR or SUITE ? */
167 PyCompilerFlags st_flags; /* Parser and compiler flags */
168 } PyST_Object;
169
170
171 static void parser_free(PyST_Object *st);
172 static int parser_compare(PyST_Object *left, PyST_Object *right);
173 static PyObject *parser_getattr(PyObject *self, char *name);
174
175
176 static
177 PyTypeObject PyST_Type = {
178 PyVarObject_HEAD_INIT(NULL, 0)
179 "parser.st", /* tp_name */
180 (int) sizeof(PyST_Object), /* tp_basicsize */
181 0, /* tp_itemsize */
182 (destructor)parser_free, /* tp_dealloc */
183 0, /* tp_print */
184 parser_getattr, /* tp_getattr */
185 0, /* tp_setattr */
186 (cmpfunc)parser_compare, /* tp_compare */
187 0, /* tp_repr */
188 0, /* tp_as_number */
189 0, /* tp_as_sequence */
190 0, /* tp_as_mapping */
191 0, /* tp_hash */
192 0, /* tp_call */
193 0, /* tp_str */
194 0, /* tp_getattro */
195 0, /* tp_setattro */
196
197 /* Functions to access object as input/output buffer */
198 0, /* tp_as_buffer */
199
200 Py_TPFLAGS_DEFAULT, /* tp_flags */
201
202 /* __doc__ */
203 "Intermediate representation of a Python parse tree."
204 }; /* PyST_Type */
205
206
207 static int
208 parser_compare_nodes(node *left, node *right)
209 {
210 int j;
211
212 if (TYPE(left) < TYPE(right))
213 return (-1);
214
215 if (TYPE(right) < TYPE(left))
216 return (1);
217
218 if (ISTERMINAL(TYPE(left)))
219 return (strcmp(STR(left), STR(right)));
220
221 if (NCH(left) < NCH(right))
222 return (-1);
223
224 if (NCH(right) < NCH(left))
225 return (1);
226
227 for (j = 0; j < NCH(left); ++j) {
228 int v = parser_compare_nodes(CHILD(left, j), CHILD(right, j));
229
230 if (v != 0)
231 return (v);
232 }
233 return (0);
234 }
235
236
237 /* int parser_compare(PyST_Object* left, PyST_Object* right)
238 *
239 * Comparison function used by the Python operators ==, !=, <, >, <=, >=
240 * This really just wraps a call to parser_compare_nodes() with some easy
241 * checks and protection code.
242 *
243 */
244 static int
245 parser_compare(PyST_Object *left, PyST_Object *right)
246 {
247 if (left == right)
248 return (0);
249
250 if ((left == 0) || (right == 0))
251 return (-1);
252
253 return (parser_compare_nodes(left->st_node, right->st_node));
254 }
255
256
257 /* parser_newstobject(node* st)
258 *
259 * Allocates a new Python object representing an ST. This is simply the
260 * 'wrapper' object that holds a node* and allows it to be passed around in
261 * Python code.
262 *
263 */
264 static PyObject*
265 parser_newstobject(node *st, int type)
266 {
267 PyST_Object* o = PyObject_New(PyST_Object, &PyST_Type);
268
269 if (o != 0) {
270 o->st_node = st;
271 o->st_type = type;
272 o->st_flags.cf_flags = 0;
273 }
274 else {
275 PyNode_Free(st);
276 }
277 return ((PyObject*)o);
278 }
279
280
281 /* void parser_free(PyST_Object* st)
282 *
283 * This is called by a del statement that reduces the reference count to 0.
284 *
285 */
286 static void
287 parser_free(PyST_Object *st)
288 {
289 PyNode_Free(st->st_node);
290 PyObject_Del(st);
291 }
292
293
294 /* parser_st2tuple(PyObject* self, PyObject* args, PyObject* kw)
295 *
296 * This provides conversion from a node* to a tuple object that can be
297 * returned to the Python-level caller. The ST object is not modified.
298 *
299 */
300 static PyObject*
301 parser_st2tuple(PyST_Object *self, PyObject *args, PyObject *kw)
302 {
303 PyObject *line_option = 0;
304 PyObject *col_option = 0;
305 PyObject *res = 0;
306 int ok;
307
308 static char *keywords[] = {"ast", "line_info", "col_info", NULL};
309
310 if (self == NULL) {
311 ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|OO:st2tuple", keywords,
312 &PyST_Type, &self, &line_option,
313 &col_option);
314 }
315 else
316 ok = PyArg_ParseTupleAndKeywords(args, kw, "|OO:totuple", &keywords[1],
317 &line_option, &col_option);
318 if (ok != 0) {
319 int lineno = 0;
320 int col_offset = 0;
321 if (line_option != NULL) {
322 lineno = (PyObject_IsTrue(line_option) != 0) ? 1 : 0;
323 }
324 if (col_option != NULL) {
325 col_offset = (PyObject_IsTrue(col_option) != 0) ? 1 : 0;
326 }
327 /*
328 * Convert ST into a tuple representation. Use Guido's function,
329 * since it's known to work already.
330 */
331 res = node2tuple(((PyST_Object*)self)->st_node,
332 PyTuple_New, PyTuple_SetItem, lineno, col_offset);
333 }
334 return (res);
335 }
336
337 static PyObject*
338 parser_ast2tuple(PyST_Object *self, PyObject *args, PyObject *kw)
339 {
340 if (PyErr_WarnPy3k("ast2tuple is removed in 3.x; use st2tuple", 1) < 0)
341 return NULL;
342 return parser_st2tuple(self, args, kw);
343 }
344
345
346 /* parser_st2list(PyObject* self, PyObject* args, PyObject* kw)
347 *
348 * This provides conversion from a node* to a list object that can be
349 * returned to the Python-level caller. The ST object is not modified.
350 *
351 */
352 static PyObject*
353 parser_st2list(PyST_Object *self, PyObject *args, PyObject *kw)
354 {
355 PyObject *line_option = 0;
356 PyObject *col_option = 0;
357 PyObject *res = 0;
358 int ok;
359
360 static char *keywords[] = {"ast", "line_info", "col_info", NULL};
361
362 if (self == NULL)
363 ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|OO:st2list", keywords,
364 &PyST_Type, &self, &line_option,
365 &col_option);
366 else
367 ok = PyArg_ParseTupleAndKeywords(args, kw, "|OO:tolist", &keywords[1],
368 &line_option, &col_option);
369 if (ok) {
370 int lineno = 0;
371 int col_offset = 0;
372 if (line_option != 0) {
373 lineno = PyObject_IsTrue(line_option) ? 1 : 0;
374 }
375 if (col_option != NULL) {
376 col_offset = (PyObject_IsTrue(col_option) != 0) ? 1 : 0;
377 }
378 /*
379 * Convert ST into a tuple representation. Use Guido's function,
380 * since it's known to work already.
381 */
382 res = node2tuple(self->st_node,
383 PyList_New, PyList_SetItem, lineno, col_offset);
384 }
385 return (res);
386 }
387
388 static PyObject*
389 parser_ast2list(PyST_Object *self, PyObject *args, PyObject *kw)
390 {
391 if (PyErr_WarnPy3k("ast2list is removed in 3.x; use st2list", 1) < 0)
392 return NULL;
393 return parser_st2list(self, args, kw);
394 }
395
396
397 /* parser_compilest(PyObject* self, PyObject* args)
398 *
399 * This function creates code objects from the parse tree represented by
400 * the passed-in data object. An optional file name is passed in as well.
401 *
402 */
403 static PyObject*
404 parser_compilest(PyST_Object *self, PyObject *args, PyObject *kw)
405 {
406 PyObject* res = 0;
407 PyArena* arena;
408 mod_ty mod;
409 char* str = "<syntax-tree>";
410 int ok;
411
412 static char *keywords[] = {"ast", "filename", NULL};
413
414 if (self == NULL)
415 ok = PyArg_ParseTupleAndKeywords(args, kw, "O!|s:compilest", keywords,
416 &PyST_Type, &self, &str);
417 else
418 ok = PyArg_ParseTupleAndKeywords(args, kw, "|s:compile", &keywords[1],
419 &str);
420
421 if (ok) {
422 arena = PyArena_New();
423 if (arena) {
424 mod = PyAST_FromNode(self->st_node, &(self->st_flags), str, arena);
425 if (mod) {
426 res = (PyObject *)PyAST_Compile(mod, str, &(self->st_flags), arena);
427 }
428 PyArena_Free(arena);
429 }
430 }
431
432 return (res);
433 }
434
435 static PyObject*
436 parser_compileast(PyST_Object *self, PyObject *args, PyObject *kw)
437 {
438 if (PyErr_WarnPy3k("compileast is removed in 3.x; use compilest", 1) < 0)
439 return NULL;
440 return parser_compilest(self, args, kw);
441 }
442
443
444 /* PyObject* parser_isexpr(PyObject* self, PyObject* args)
445 * PyObject* parser_issuite(PyObject* self, PyObject* args)
446 *
447 * Checks the passed-in ST object to determine if it is an expression or
448 * a statement suite, respectively. The return is a Python truth value.
449 *
450 */
451 static PyObject*
452 parser_isexpr(PyST_Object *self, PyObject *args, PyObject *kw)
453 {
454 PyObject* res = 0;
455 int ok;
456
457 static char *keywords[] = {"ast", NULL};
458
459 if (self == NULL)
460 ok = PyArg_ParseTupleAndKeywords(args, kw, "O!:isexpr", keywords,
461 &PyST_Type, &self);
462 else
463 ok = PyArg_ParseTupleAndKeywords(args, kw, ":isexpr", &keywords[1]);
464
465 if (ok) {
466 /* Check to see if the ST represents an expression or not. */
467 res = (self->st_type == PyST_EXPR) ? Py_True : Py_False;
468 Py_INCREF(res);
469 }
470 return (res);
471 }
472
473
474 static PyObject*
475 parser_issuite(PyST_Object *self, PyObject *args, PyObject *kw)
476 {
477 PyObject* res = 0;
478 int ok;
479
480 static char *keywords[] = {"ast", NULL};
481
482 if (self == NULL)
483 ok = PyArg_ParseTupleAndKeywords(args, kw, "O!:issuite", keywords,
484 &PyST_Type, &self);
485 else
486 ok = PyArg_ParseTupleAndKeywords(args, kw, ":issuite", &keywords[1]);
487
488 if (ok) {
489 /* Check to see if the ST represents an expression or not. */
490 res = (self->st_type == PyST_EXPR) ? Py_False : Py_True;
491 Py_INCREF(res);
492 }
493 return (res);
494 }
495
496
497 #define PUBLIC_METHOD_TYPE (METH_VARARGS|METH_KEYWORDS)
498
499 static PyMethodDef
500 parser_methods[] = {
501 {"compile", (PyCFunction)parser_compilest, PUBLIC_METHOD_TYPE,
502 PyDoc_STR("Compile this ST object into a code object.")},
503 {"isexpr", (PyCFunction)parser_isexpr, PUBLIC_METHOD_TYPE,
504 PyDoc_STR("Determines if this ST object was created from an expression.")},
505 {"issuite", (PyCFunction)parser_issuite, PUBLIC_METHOD_TYPE,
506 PyDoc_STR("Determines if this ST object was created from a suite.")},
507 {"tolist", (PyCFunction)parser_st2list, PUBLIC_METHOD_TYPE,
508 PyDoc_STR("Creates a list-tree representation of this ST.")},
509 {"totuple", (PyCFunction)parser_st2tuple, PUBLIC_METHOD_TYPE,
510 PyDoc_STR("Creates a tuple-tree representation of this ST.")},
511
512 {NULL, NULL, 0, NULL}
513 };
514
515
516 static PyObject*
517 parser_getattr(PyObject *self, char *name)
518 {
519 return (Py_FindMethod(parser_methods, self, name));
520 }
521
522
523 /* err_string(char* message)
524 *
525 * Sets the error string for an exception of type ParserError.
526 *
527 */
528 static void
529 err_string(char *message)
530 {
531 PyErr_SetString(parser_error, message);
532 }
533
534
535 /* PyObject* parser_do_parse(PyObject* args, int type)
536 *
537 * Internal function to actually execute the parse and return the result if
538 * successful or set an exception if not.
539 *
540 */
541 static PyObject*
542 parser_do_parse(PyObject *args, PyObject *kw, char *argspec, int type)
543 {
544 char* string = 0;
545 PyObject* res = 0;
546 int flags = 0;
547 perrdetail err;
548
549 static char *keywords[] = {"source", NULL};
550
551 if (PyArg_ParseTupleAndKeywords(args, kw, argspec, keywords, &string)) {
552 node* n = PyParser_ParseStringFlagsFilenameEx(string, NULL,
553 &_PyParser_Grammar,
554 (type == PyST_EXPR)
555 ? eval_input : file_input,
556 &err, &flags);
557
558 if (n) {
559 res = parser_newstobject(n, type);
560 if (res)
561 ((PyST_Object *)res)->st_flags.cf_flags = flags & PyCF_MASK;
562 }
563 else
564 PyParser_SetError(&err);
565 }
566 return (res);
567 }
568
569
570 /* PyObject* parser_expr(PyObject* self, PyObject* args)
571 * PyObject* parser_suite(PyObject* self, PyObject* args)
572 *
573 * External interfaces to the parser itself. Which is called determines if
574 * the parser attempts to recognize an expression ('eval' form) or statement
575 * suite ('exec' form). The real work is done by parser_do_parse() above.
576 *
577 */
578 static PyObject*
579 parser_expr(PyST_Object *self, PyObject *args, PyObject *kw)
580 {
581 NOTE(ARGUNUSED(self))
582 return (parser_do_parse(args, kw, "s:expr", PyST_EXPR));
583 }
584
585
586 static PyObject*
587 parser_suite(PyST_Object *self, PyObject *args, PyObject *kw)
588 {
589 NOTE(ARGUNUSED(self))
590 return (parser_do_parse(args, kw, "s:suite", PyST_SUITE));
591 }
592
593
594
595 /* This is the messy part of the code. Conversion from a tuple to an ST
596 * object requires that the input tuple be valid without having to rely on
597 * catching an exception from the compiler. This is done to allow the
598 * compiler itself to remain fast, since most of its input will come from
599 * the parser directly, and therefore be known to be syntactically correct.
600 * This validation is done to ensure that we don't core dump the compile
601 * phase, returning an exception instead.
602 *
603 * Two aspects can be broken out in this code: creating a node tree from
604 * the tuple passed in, and verifying that it is indeed valid. It may be
605 * advantageous to expand the number of ST types to include funcdefs and
606 * lambdadefs to take advantage of the optimizer, recognizing those STs
607 * here. They are not necessary, and not quite as useful in a raw form.
608 * For now, let's get expressions and suites working reliably.
609 */
610
611
612 static node* build_node_tree(PyObject *tuple);
613 static int validate_expr_tree(node *tree);
614 static int validate_file_input(node *tree);
615 static int validate_encoding_decl(node *tree);
616
617 /* PyObject* parser_tuple2st(PyObject* self, PyObject* args)
618 *
619 * This is the public function, called from the Python code. It receives a
620 * single tuple object from the caller, and creates an ST object if the
621 * tuple can be validated. It does this by checking the first code of the
622 * tuple, and, if acceptable, builds the internal representation. If this
623 * step succeeds, the internal representation is validated as fully as
624 * possible with the various validate_*() routines defined below.
625 *
626 * This function must be changed if support is to be added for PyST_FRAGMENT
627 * ST objects.
628 *
629 */
630 static PyObject*
631 parser_tuple2st(PyST_Object *self, PyObject *args, PyObject *kw)
632 {
633 NOTE(ARGUNUSED(self))
634 PyObject *st = 0;
635 PyObject *tuple;
636 node *tree;
637
638 static char *keywords[] = {"sequence", NULL};
639
640 if (!PyArg_ParseTupleAndKeywords(args, kw, "O:sequence2st", keywords,
641 &tuple))
642 return (0);
643 if (!PySequence_Check(tuple)) {
644 PyErr_SetString(PyExc_ValueError,
645 "sequence2st() requires a single sequence argument");
646 return (0);
647 }
648 /*
649 * Convert the tree to the internal form before checking it.
650 */
651 tree = build_node_tree(tuple);
652 if (tree != 0) {
653 int start_sym = TYPE(tree);
654 if (start_sym == eval_input) {
655 /* Might be an eval form. */
656 if (validate_expr_tree(tree))
657 st = parser_newstobject(tree, PyST_EXPR);
658 else
659 PyNode_Free(tree);
660 }
661 else if (start_sym == file_input) {
662 /* This looks like an exec form so far. */
663 if (validate_file_input(tree))
664 st = parser_newstobject(tree, PyST_SUITE);
665 else
666 PyNode_Free(tree);
667 }
668 else if (start_sym == encoding_decl) {
669 /* This looks like an encoding_decl so far. */
670 if (validate_encoding_decl(tree))
671 st = parser_newstobject(tree, PyST_SUITE);
672 else
673 PyNode_Free(tree);
674 }
675 else {
676 /* This is a fragment, at best. */
677 PyNode_Free(tree);
678 err_string("parse tree does not use a valid start symbol");
679 }
680 }
681 /* Make sure we throw an exception on all errors. We should never
682 * get this, but we'd do well to be sure something is done.
683 */
684 if (st == NULL && !PyErr_Occurred())
685 err_string("unspecified ST error occurred");
686
687 return st;
688 }
689
690 static PyObject*
691 parser_tuple2ast(PyST_Object *self, PyObject *args, PyObject *kw)
692 {
693 if (PyErr_WarnPy3k("tuple2ast is removed in 3.x; use tuple2st", 1) < 0)
694 return NULL;
695 return parser_tuple2st(self, args, kw);
696 }
697
698
699 /* node* build_node_children()
700 *
701 * Iterate across the children of the current non-terminal node and build
702 * their structures. If successful, return the root of this portion of
703 * the tree, otherwise, 0. Any required exception will be specified already,
704 * and no memory will have been deallocated.
705 *
706 */
707 static node*
708 build_node_children(PyObject *tuple, node *root, int *line_num)
709 {
710 Py_ssize_t len = PyObject_Size(tuple);
711 Py_ssize_t i;
712 int err;
713
714 for (i = 1; i < len; ++i) {
715 /* elem must always be a sequence, however simple */
716 PyObject* elem = PySequence_GetItem(tuple, i);
717 int ok = elem != NULL;
718 long type = 0;
719 char *strn = 0;
720
721 if (ok)
722 ok = PySequence_Check(elem);
723 if (ok) {
724 PyObject *temp = PySequence_GetItem(elem, 0);
725 if (temp == NULL)
726 ok = 0;
727 else {
728 ok = PyInt_Check(temp);
729 if (ok)
730 type = PyInt_AS_LONG(temp);
731 Py_DECREF(temp);
732 }
733 }
734 if (!ok) {
735 PyObject *err = Py_BuildValue("os", elem,
736 "Illegal node construct.");
737 PyErr_SetObject(parser_error, err);
738 Py_XDECREF(err);
739 Py_XDECREF(elem);
740 return (0);
741 }
742 if (ISTERMINAL(type)) {
743 Py_ssize_t len = PyObject_Size(elem);
744 PyObject *temp;
745
746 if ((len != 2) && (len != 3)) {
747 err_string("terminal nodes must have 2 or 3 entries");
748 return 0;
749 }
750 temp = PySequence_GetItem(elem, 1);
751 if (temp == NULL)
752 return 0;
753 if (!PyString_Check(temp)) {
754 PyErr_Format(parser_error,
755 "second item in terminal node must be a string,"
756 " found %s",
757 Py_TYPE(temp)->tp_name);
758 Py_DECREF(temp);
759 return 0;
760 }
761 if (len == 3) {
762 PyObject *o = PySequence_GetItem(elem, 2);
763 if (o != NULL) {
764 if (PyInt_Check(o))
765 *line_num = PyInt_AS_LONG(o);
766 else {
767 PyErr_Format(parser_error,
768 "third item in terminal node must be an"
769 " integer, found %s",
770 Py_TYPE(temp)->tp_name);
771 Py_DECREF(o);
772 Py_DECREF(temp);
773 return 0;
774 }
775 Py_DECREF(o);
776 }
777 }
778 len = PyString_GET_SIZE(temp) + 1;
779 strn = (char *)PyObject_MALLOC(len);
780 if (strn != NULL)
781 (void) memcpy(strn, PyString_AS_STRING(temp), len);
782 Py_DECREF(temp);
783 }
784 else if (!ISNONTERMINAL(type)) {
785 /*
786 * It has to be one or the other; this is an error.
787 * Throw an exception.
788 */
789 PyObject *err = Py_BuildValue("os", elem, "unknown node type.");
790 PyErr_SetObject(parser_error, err);
791 Py_XDECREF(err);
792 Py_XDECREF(elem);
793 return (0);
794 }
795 err = PyNode_AddChild(root, type, strn, *line_num, 0);
796 if (err == E_NOMEM) {
797 PyObject_FREE(strn);
798 return (node *) PyErr_NoMemory();
799 }
800 if (err == E_OVERFLOW) {
801 PyObject_FREE(strn);
802 PyErr_SetString(PyExc_ValueError,
803 "unsupported number of child nodes");
804 return NULL;
805 }
806
807 if (ISNONTERMINAL(type)) {
808 node* new_child = CHILD(root, i - 1);
809
810 if (new_child != build_node_children(elem, new_child, line_num)) {
811 Py_XDECREF(elem);
812 return (0);
813 }
814 }
815 else if (type == NEWLINE) { /* It's true: we increment the */
816 ++(*line_num); /* line number *after* the newline! */
817 }
818 Py_XDECREF(elem);
819 }
820 return root;
821 }
822
823
824 static node*
825 build_node_tree(PyObject *tuple)
826 {
827 node* res = 0;
828 PyObject *temp = PySequence_GetItem(tuple, 0);
829 long num = -1;
830
831 if (temp != NULL)
832 num = PyInt_AsLong(temp);
833 Py_XDECREF(temp);
834 if (ISTERMINAL(num)) {
835 /*
836 * The tuple is simple, but it doesn't start with a start symbol.
837 * Throw an exception now and be done with it.
838 */
839 tuple = Py_BuildValue("os", tuple,
840 "Illegal syntax-tree; cannot start with terminal symbol.");
841 PyErr_SetObject(parser_error, tuple);
842 Py_XDECREF(tuple);
843 }
844 else if (ISNONTERMINAL(num)) {
845 /*
846 * Not efficient, but that can be handled later.
847 */
848 int line_num = 0;
849 PyObject *encoding = NULL;
850
851 if (num == encoding_decl) {
852 encoding = PySequence_GetItem(tuple, 2);
853 /* tuple isn't borrowed anymore here, need to DECREF */
854 tuple = PySequence_GetSlice(tuple, 0, 2);
855 }
856 res = PyNode_New(num);
857 if (res != NULL) {
858 if (res != build_node_children(tuple, res, &line_num)) {
859 PyNode_Free(res);
860 res = NULL;
861 }
862 if (res && encoding) {
863 Py_ssize_t len;
864 len = PyString_GET_SIZE(encoding) + 1;
865 res->n_str = (char *)PyObject_MALLOC(len);
866 if (res->n_str != NULL)
867 (void) memcpy(res->n_str, PyString_AS_STRING(encoding), len);
868 Py_DECREF(encoding);
869 Py_DECREF(tuple);
870 }
871 }
872 }
873 else {
874 /* The tuple is illegal -- if the number is neither TERMINAL nor
875 * NONTERMINAL, we can't use it. Not sure the implementation
876 * allows this condition, but the API doesn't preclude it.
877 */
878 PyObject *err = Py_BuildValue("os", tuple,
879 "Illegal component tuple.");
880 PyErr_SetObject(parser_error, err);
881 Py_XDECREF(err);
882 }
883
884 return (res);
885 }
886
887
888 /*
889 * Validation routines used within the validation section:
890 */
891 static int validate_terminal(node *terminal, int type, char *string);
892
893 #define validate_ampersand(ch) validate_terminal(ch, AMPER, "&")
894 #define validate_circumflex(ch) validate_terminal(ch, CIRCUMFLEX, "^")
895 #define validate_colon(ch) validate_terminal(ch, COLON, ":")
896 #define validate_comma(ch) validate_terminal(ch, COMMA, ",")
897 #define validate_dedent(ch) validate_terminal(ch, DEDENT, "")
898 #define validate_equal(ch) validate_terminal(ch, EQUAL, "=")
899 #define validate_indent(ch) validate_terminal(ch, INDENT, (char*)NULL)
900 #define validate_lparen(ch) validate_terminal(ch, LPAR, "(")
901 #define validate_newline(ch) validate_terminal(ch, NEWLINE, (char*)NULL)
902 #define validate_rparen(ch) validate_terminal(ch, RPAR, ")")
903 #define validate_semi(ch) validate_terminal(ch, SEMI, ";")
904 #define validate_star(ch) validate_terminal(ch, STAR, "*")
905 #define validate_vbar(ch) validate_terminal(ch, VBAR, "|")
906 #define validate_doublestar(ch) validate_terminal(ch, DOUBLESTAR, "**")
907 #define validate_dot(ch) validate_terminal(ch, DOT, ".")
908 #define validate_at(ch) validate_terminal(ch, AT, "@")
909 #define validate_name(ch, str) validate_terminal(ch, NAME, str)
910
911 #define VALIDATER(n) static int validate_##n(node *tree)
912
913 VALIDATER(node); VALIDATER(small_stmt);
914 VALIDATER(class); VALIDATER(node);
915 VALIDATER(parameters); VALIDATER(suite);
916 VALIDATER(testlist); VALIDATER(varargslist);
917 VALIDATER(fpdef); VALIDATER(fplist);
918 VALIDATER(stmt); VALIDATER(simple_stmt);
919 VALIDATER(expr_stmt); VALIDATER(power);
920 VALIDATER(print_stmt); VALIDATER(del_stmt);
921 VALIDATER(return_stmt); VALIDATER(list_iter);
922 VALIDATER(raise_stmt); VALIDATER(import_stmt);
923 VALIDATER(import_name); VALIDATER(import_from);
924 VALIDATER(global_stmt); VALIDATER(list_if);
925 VALIDATER(assert_stmt); VALIDATER(list_for);
926 VALIDATER(exec_stmt); VALIDATER(compound_stmt);
927 VALIDATER(while); VALIDATER(for);
928 VALIDATER(try); VALIDATER(except_clause);
929 VALIDATER(test); VALIDATER(and_test);
930 VALIDATER(not_test); VALIDATER(comparison);
931 VALIDATER(comp_op); VALIDATER(expr);
932 VALIDATER(xor_expr); VALIDATER(and_expr);
933 VALIDATER(shift_expr); VALIDATER(arith_expr);
934 VALIDATER(term); VALIDATER(factor);
935 VALIDATER(atom); VALIDATER(lambdef);
936 VALIDATER(trailer); VALIDATER(subscript);
937 VALIDATER(subscriptlist); VALIDATER(sliceop);
938 VALIDATER(exprlist); VALIDATER(dictorsetmaker);
939 VALIDATER(arglist); VALIDATER(argument);
940 VALIDATER(listmaker); VALIDATER(yield_stmt);
941 VALIDATER(testlist1); VALIDATER(comp_for);
942 VALIDATER(comp_iter); VALIDATER(comp_if);
943 VALIDATER(testlist_comp); VALIDATER(yield_expr);
944 VALIDATER(yield_or_testlist); VALIDATER(or_test);
945 VALIDATER(old_test); VALIDATER(old_lambdef);
946
947 #undef VALIDATER
948
949 #define is_even(n) (((n) & 1) == 0)
950 #define is_odd(n) (((n) & 1) == 1)
951
952
953 static int
954 validate_ntype(node *n, int t)
955 {
956 if (TYPE(n) != t) {
957 PyErr_Format(parser_error, "Expected node type %d, got %d.",
958 t, TYPE(n));
959 return 0;
960 }
961 return 1;
962 }
963
964
965 /* Verifies that the number of child nodes is exactly 'num', raising
966 * an exception if it isn't. The exception message does not indicate
967 * the exact number of nodes, allowing this to be used to raise the
968 * "right" exception when the wrong number of nodes is present in a
969 * specific variant of a statement's syntax. This is commonly used
970 * in that fashion.
971 */
972 static int
973 validate_numnodes(node *n, int num, const char *const name)
974 {
975 if (NCH(n) != num) {
976 PyErr_Format(parser_error,
977 "Illegal number of children for %s node.", name);
978 return 0;
979 }
980 return 1;
981 }
982
983
984 static int
985 validate_terminal(node *terminal, int type, char *string)
986 {
987 int res = (validate_ntype(terminal, type)
988 && ((string == 0) || (strcmp(string, STR(terminal)) == 0)));
989
990 if (!res && !PyErr_Occurred()) {
991 PyErr_Format(parser_error,
992 "Illegal terminal: expected \"%s\"", string);
993 }
994 return (res);
995 }
996
997
998 /* X (',' X) [',']
999 */
1000 static int
1001 validate_repeating_list(node *tree, int ntype, int (*vfunc)(node *),
1002 const char *const name)
1003 {
1004 int nch = NCH(tree);
1005 int res = (nch && validate_ntype(tree, ntype)
1006 && vfunc(CHILD(tree, 0)));
1007
1008 if (!res && !PyErr_Occurred())
1009 (void) validate_numnodes(tree, 1, name);
1010 else {
1011 if (is_even(nch))
1012 res = validate_comma(CHILD(tree, --nch));
1013 if (res && nch > 1) {
1014 int pos = 1;
1015 for ( ; res && pos < nch; pos += 2)
1016 res = (validate_comma(CHILD(tree, pos))
1017 && vfunc(CHILD(tree, pos + 1)));
1018 }
1019 }
1020 return (res);
1021 }
1022
1023
1024 /* validate_class()
1025 *
1026 * classdef:
1027 * 'class' NAME ['(' testlist ')'] ':' suite
1028 */
1029 static int
1030 validate_class(node *tree)
1031 {
1032 int nch = NCH(tree);
1033 int res = (validate_ntype(tree, classdef) &&
1034 ((nch == 4) || (nch == 6) || (nch == 7)));
1035
1036 if (res) {
1037 res = (validate_name(CHILD(tree, 0), "class")
1038 && validate_ntype(CHILD(tree, 1), NAME)
1039 && validate_colon(CHILD(tree, nch - 2))
1040 && validate_suite(CHILD(tree, nch - 1)));
1041 }
1042 else {
1043 (void) validate_numnodes(tree, 4, "class");
1044 }
1045
1046 if (res) {
1047 if (nch == 7) {
1048 res = ((validate_lparen(CHILD(tree, 2)) &&
1049 validate_testlist(CHILD(tree, 3)) &&
1050 validate_rparen(CHILD(tree, 4))));
1051 }
1052 else if (nch == 6) {
1053 res = (validate_lparen(CHILD(tree,2)) &&
1054 validate_rparen(CHILD(tree,3)));
1055 }
1056 }
1057 return (res);
1058 }
1059
1060
1061 /* if_stmt:
1062 * 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
1063 */
1064 static int
1065 validate_if(node *tree)
1066 {
1067 int nch = NCH(tree);
1068 int res = (validate_ntype(tree, if_stmt)
1069 && (nch >= 4)
1070 && validate_name(CHILD(tree, 0), "if")
1071 && validate_test(CHILD(tree, 1))
1072 && validate_colon(CHILD(tree, 2))
1073 && validate_suite(CHILD(tree, 3)));
1074
1075 if (res && ((nch % 4) == 3)) {
1076 /* ... 'else' ':' suite */
1077 res = (validate_name(CHILD(tree, nch - 3), "else")
1078 && validate_colon(CHILD(tree, nch - 2))
1079 && validate_suite(CHILD(tree, nch - 1)));
1080 nch -= 3;
1081 }
1082 else if (!res && !PyErr_Occurred())
1083 (void) validate_numnodes(tree, 4, "if");
1084 if ((nch % 4) != 0)
1085 /* Will catch the case for nch < 4 */
1086 res = validate_numnodes(tree, 0, "if");
1087 else if (res && (nch > 4)) {
1088 /* ... ('elif' test ':' suite)+ ... */
1089 int j = 4;
1090 while ((j < nch) && res) {
1091 res = (validate_name(CHILD(tree, j), "elif")
1092 && validate_colon(CHILD(tree, j + 2))
1093 && validate_test(CHILD(tree, j + 1))
1094 && validate_suite(CHILD(tree, j + 3)));
1095 j += 4;
1096 }
1097 }
1098 return (res);
1099 }
1100
1101
1102 /* parameters:
1103 * '(' [varargslist] ')'
1104 *
1105 */
1106 static int
1107 validate_parameters(node *tree)
1108 {
1109 int nch = NCH(tree);
1110 int res = validate_ntype(tree, parameters) && ((nch == 2) || (nch == 3));
1111
1112 if (res) {
1113 res = (validate_lparen(CHILD(tree, 0))
1114 && validate_rparen(CHILD(tree, nch - 1)));
1115 if (res && (nch == 3))
1116 res = validate_varargslist(CHILD(tree, 1));
1117 }
1118 else {
1119 (void) validate_numnodes(tree, 2, "parameters");
1120 }
1121 return (res);
1122 }
1123
1124
1125 /* validate_suite()
1126 *
1127 * suite:
1128 * simple_stmt
1129 * | NEWLINE INDENT stmt+ DEDENT
1130 */
1131 static int
1132 validate_suite(node *tree)
1133 {
1134 int nch = NCH(tree);
1135 int res = (validate_ntype(tree, suite) && ((nch == 1) || (nch >= 4)));
1136
1137 if (res && (nch == 1))
1138 res = validate_simple_stmt(CHILD(tree, 0));
1139 else if (res) {
1140 /* NEWLINE INDENT stmt+ DEDENT */
1141 res = (validate_newline(CHILD(tree, 0))
1142 && validate_indent(CHILD(tree, 1))
1143 && validate_stmt(CHILD(tree, 2))
1144 && validate_dedent(CHILD(tree, nch - 1)));
1145
1146 if (res && (nch > 4)) {
1147 int i = 3;
1148 --nch; /* forget the DEDENT */
1149 for ( ; res && (i < nch); ++i)
1150 res = validate_stmt(CHILD(tree, i));
1151 }
1152 else if (nch < 4)
1153 res = validate_numnodes(tree, 4, "suite");
1154 }
1155 return (res);
1156 }
1157
1158
1159 static int
1160 validate_testlist(node *tree)
1161 {
1162 return (validate_repeating_list(tree, testlist,
1163 validate_test, "testlist"));
1164 }
1165
1166
1167 static int
1168 validate_testlist1(node *tree)
1169 {
1170 return (validate_repeating_list(tree, testlist1,
1171 validate_test, "testlist1"));
1172 }
1173
1174
1175 static int
1176 validate_testlist_safe(node *tree)
1177 {
1178 return (validate_repeating_list(tree, testlist_safe,
1179 validate_old_test, "testlist_safe"));
1180 }
1181
1182
1183 /* '*' NAME [',' '**' NAME] | '**' NAME
1184 */
1185 static int
1186 validate_varargslist_trailer(node *tree, int start)
1187 {
1188 int nch = NCH(tree);
1189 int res = 0;
1190 int sym;
1191
1192 if (nch <= start) {
1193 err_string("expected variable argument trailer for varargslist");
1194 return 0;
1195 }
1196 sym = TYPE(CHILD(tree, start));
1197 if (sym == STAR) {
1198 /*
1199 * ('*' NAME [',' '**' NAME]
1200 */
1201 if (nch-start == 2)
1202 res = validate_name(CHILD(tree, start+1), NULL);
1203 else if (nch-start == 5)
1204 res = (validate_name(CHILD(tree, start+1), NULL)
1205 && validate_comma(CHILD(tree, start+2))
1206 && validate_doublestar(CHILD(tree, start+3))
1207 && validate_name(CHILD(tree, start+4), NULL));
1208 }
1209 else if (sym == DOUBLESTAR) {
1210 /*
1211 * '**' NAME
1212 */
1213 if (nch-start == 2)
1214 res = validate_name(CHILD(tree, start+1), NULL);
1215 }
1216 if (!res)
1217 err_string("illegal variable argument trailer for varargslist");
1218 return res;
1219 }
1220
1221
1222 /* validate_varargslist()
1223 *
1224 * varargslist:
1225 * (fpdef ['=' test] ',')*
1226 * ('*' NAME [',' '**' NAME]
1227 * | '**' NAME)
1228 * | fpdef ['=' test] (',' fpdef ['=' test])* [',']
1229 *
1230 */
1231 static int
1232 validate_varargslist(node *tree)
1233 {
1234 int nch = NCH(tree);
1235 int res = validate_ntype(tree, varargslist) && (nch != 0);
1236 int sym;
1237
1238 if (!res)
1239 return 0;
1240 if (nch < 1) {
1241 err_string("varargslist missing child nodes");
1242 return 0;
1243 }
1244 sym = TYPE(CHILD(tree, 0));
1245 if (sym == STAR || sym == DOUBLESTAR)
1246 /* whole thing matches:
1247 * '*' NAME [',' '**' NAME] | '**' NAME
1248 */
1249 res = validate_varargslist_trailer(tree, 0);
1250 else if (sym == fpdef) {
1251 int i = 0;
1252
1253 sym = TYPE(CHILD(tree, nch-1));
1254 if (sym == NAME) {
1255 /*
1256 * (fpdef ['=' test] ',')+
1257 * ('*' NAME [',' '**' NAME]
1258 * | '**' NAME)
1259 */
1260 /* skip over (fpdef ['=' test] ',')+ */
1261 while (res && (i+2 <= nch)) {
1262 res = validate_fpdef(CHILD(tree, i));
1263 ++i;
1264 if (res && TYPE(CHILD(tree, i)) == EQUAL && (i+2 <= nch)) {
1265 res = (validate_equal(CHILD(tree, i))
1266 && validate_test(CHILD(tree, i+1)));
1267 if (res)
1268 i += 2;
1269 }
1270 if (res && i < nch) {
1271 res = validate_comma(CHILD(tree, i));
1272 ++i;
1273 if (res && i < nch
1274 && (TYPE(CHILD(tree, i)) == DOUBLESTAR
1275 || TYPE(CHILD(tree, i)) == STAR))
1276 break;
1277 }
1278 }
1279 /* ... '*' NAME [',' '**' NAME] | '**' NAME
1280 * i --^^^
1281 */
1282 if (res)
1283 res = validate_varargslist_trailer(tree, i);
1284 }
1285 else {
1286 /*
1287 * fpdef ['=' test] (',' fpdef ['=' test])* [',']
1288 */
1289 /* strip trailing comma node */
1290 if (sym == COMMA) {
1291 res = validate_comma(CHILD(tree, nch-1));
1292 if (!res)
1293 return 0;
1294 --nch;
1295 }
1296 /*
1297 * fpdef ['=' test] (',' fpdef ['=' test])*
1298 */
1299 res = validate_fpdef(CHILD(tree, 0));
1300 ++i;
1301 if (res && (i+2 <= nch) && TYPE(CHILD(tree, i)) == EQUAL) {
1302 res = (validate_equal(CHILD(tree, i))
1303 && validate_test(CHILD(tree, i+1)));
1304 i += 2;
1305 }
1306 /*
1307 * ... (',' fpdef ['=' test])*
1308 * i ---^^^
1309 */
1310 while (res && (nch - i) >= 2) {
1311 res = (validate_comma(CHILD(tree, i))
1312 && validate_fpdef(CHILD(tree, i+1)));
1313 i += 2;
1314 if (res && (nch - i) >= 2 && TYPE(CHILD(tree, i)) == EQUAL) {
1315 res = (validate_equal(CHILD(tree, i))
1316 && validate_test(CHILD(tree, i+1)));
1317 i += 2;
1318 }
1319 }
1320 if (res && nch - i != 0) {
1321 res = 0;
1322 err_string("illegal formation for varargslist");
1323 }
1324 }
1325 }
1326 return res;
1327 }
1328
1329
1330 /* list_iter: list_for | list_if
1331 */
1332 static int
1333 validate_list_iter(node *tree)
1334 {
1335 int res = (validate_ntype(tree, list_iter)
1336 && validate_numnodes(tree, 1, "list_iter"));
1337 if (res && TYPE(CHILD(tree, 0)) == list_for)
1338 res = validate_list_for(CHILD(tree, 0));
1339 else
1340 res = validate_list_if(CHILD(tree, 0));
1341
1342 return res;
1343 }
1344
1345 /* comp_iter: comp_for | comp_if
1346 */
1347 static int
1348 validate_comp_iter(node *tree)
1349 {
1350 int res = (validate_ntype(tree, comp_iter)
1351 && validate_numnodes(tree, 1, "comp_iter"));
1352 if (res && TYPE(CHILD(tree, 0)) == comp_for)
1353 res = validate_comp_for(CHILD(tree, 0));
1354 else
1355 res = validate_comp_if(CHILD(tree, 0));
1356
1357 return res;
1358 }
1359
1360 /* list_for: 'for' exprlist 'in' testlist [list_iter]
1361 */
1362 static int
1363 validate_list_for(node *tree)
1364 {
1365 int nch = NCH(tree);
1366 int res;
1367
1368 if (nch == 5)
1369 res = validate_list_iter(CHILD(tree, 4));
1370 else
1371 res = validate_numnodes(tree, 4, "list_for");
1372
1373 if (res)
1374 res = (validate_name(CHILD(tree, 0), "for")
1375 && validate_exprlist(CHILD(tree, 1))
1376 && validate_name(CHILD(tree, 2), "in")
1377 && validate_testlist_safe(CHILD(tree, 3)));
1378
1379 return res;
1380 }
1381
1382 /* comp_for: 'for' exprlist 'in' test [comp_iter]
1383 */
1384 static int
1385 validate_comp_for(node *tree)
1386 {
1387 int nch = NCH(tree);
1388 int res;
1389
1390 if (nch == 5)
1391 res = validate_comp_iter(CHILD(tree, 4));
1392 else
1393 res = validate_numnodes(tree, 4, "comp_for");
1394
1395 if (res)
1396 res = (validate_name(CHILD(tree, 0), "for")
1397 && validate_exprlist(CHILD(tree, 1))
1398 && validate_name(CHILD(tree, 2), "in")
1399 && validate_or_test(CHILD(tree, 3)));
1400
1401 return res;
1402 }
1403
1404 /* list_if: 'if' old_test [list_iter]
1405 */
1406 static int
1407 validate_list_if(node *tree)
1408 {
1409 int nch = NCH(tree);
1410 int res;
1411
1412 if (nch == 3)
1413 res = validate_list_iter(CHILD(tree, 2));
1414 else
1415 res = validate_numnodes(tree, 2, "list_if");
1416
1417 if (res)
1418 res = (validate_name(CHILD(tree, 0), "if")
1419 && validate_old_test(CHILD(tree, 1)));
1420
1421 return res;
1422 }
1423
1424 /* comp_if: 'if' old_test [comp_iter]
1425 */
1426 static int
1427 validate_comp_if(node *tree)
1428 {
1429 int nch = NCH(tree);
1430 int res;
1431
1432 if (nch == 3)
1433 res = validate_comp_iter(CHILD(tree, 2));
1434 else
1435 res = validate_numnodes(tree, 2, "comp_if");
1436
1437 if (res)
1438 res = (validate_name(CHILD(tree, 0), "if")
1439 && validate_old_test(CHILD(tree, 1)));
1440
1441 return res;
1442 }
1443
1444 /* validate_fpdef()
1445 *
1446 * fpdef:
1447 * NAME
1448 * | '(' fplist ')'
1449 */
1450 static int
1451 validate_fpdef(node *tree)
1452 {
1453 int nch = NCH(tree);
1454 int res = validate_ntype(tree, fpdef);
1455
1456 if (res) {
1457 if (nch == 1)
1458 res = validate_ntype(CHILD(tree, 0), NAME);
1459 else if (nch == 3)
1460 res = (validate_lparen(CHILD(tree, 0))
1461 && validate_fplist(CHILD(tree, 1))
1462 && validate_rparen(CHILD(tree, 2)));
1463 else
1464 res = validate_numnodes(tree, 1, "fpdef");
1465 }
1466 return (res);
1467 }
1468
1469
1470 static int
1471 validate_fplist(node *tree)
1472 {
1473 return (validate_repeating_list(tree, fplist,
1474 validate_fpdef, "fplist"));
1475 }
1476
1477
1478 /* simple_stmt | compound_stmt
1479 *
1480 */
1481 static int
1482 validate_stmt(node *tree)
1483 {
1484 int res = (validate_ntype(tree, stmt)
1485 && validate_numnodes(tree, 1, "stmt"));
1486
1487 if (res) {
1488 tree = CHILD(tree, 0);
1489
1490 if (TYPE(tree) == simple_stmt)
1491 res = validate_simple_stmt(tree);
1492 else
1493 res = validate_compound_stmt(tree);
1494 }
1495 return (res);
1496 }
1497
1498
1499 /* small_stmt (';' small_stmt)* [';'] NEWLINE
1500 *
1501 */
1502 static int
1503 validate_simple_stmt(node *tree)
1504 {
1505 int nch = NCH(tree);
1506 int res = (validate_ntype(tree, simple_stmt)
1507 && (nch >= 2)
1508 && validate_small_stmt(CHILD(tree, 0))
1509 && validate_newline(CHILD(tree, nch - 1)));
1510
1511 if (nch < 2)
1512 res = validate_numnodes(tree, 2, "simple_stmt");
1513 --nch; /* forget the NEWLINE */
1514 if (res && is_even(nch))
1515 res = validate_semi(CHILD(tree, --nch));
1516 if (res && (nch > 2)) {
1517 int i;
1518
1519 for (i = 1; res && (i < nch); i += 2)
1520 res = (validate_semi(CHILD(tree, i))
1521 && validate_small_stmt(CHILD(tree, i + 1)));
1522 }
1523 return (res);
1524 }
1525
1526
1527 static int
1528 validate_small_stmt(node *tree)
1529 {
1530 int nch = NCH(tree);
1531 int res = validate_numnodes(tree, 1, "small_stmt");
1532
1533 if (res) {
1534 int ntype = TYPE(CHILD(tree, 0));
1535
1536 if ( (ntype == expr_stmt)
1537 || (ntype == print_stmt)
1538 || (ntype == del_stmt)
1539 || (ntype == pass_stmt)
1540 || (ntype == flow_stmt)
1541 || (ntype == import_stmt)
1542 || (ntype == global_stmt)
1543 || (ntype == assert_stmt)
1544 || (ntype == exec_stmt))
1545 res = validate_node(CHILD(tree, 0));
1546 else {
1547 res = 0;
1548 err_string("illegal small_stmt child type");
1549 }
1550 }
1551 else if (nch == 1) {
1552 res = 0;
1553 PyErr_Format(parser_error,
1554 "Unrecognized child node of small_stmt: %d.",
1555 TYPE(CHILD(tree, 0)));
1556 }
1557 return (res);
1558 }
1559
1560
1561 /* compound_stmt:
1562 * if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated
1563 */
1564 static int
1565 validate_compound_stmt(node *tree)
1566 {
1567 int res = (validate_ntype(tree, compound_stmt)
1568 && validate_numnodes(tree, 1, "compound_stmt"));
1569 int ntype;
1570
1571 if (!res)
1572 return (0);
1573
1574 tree = CHILD(tree, 0);
1575 ntype = TYPE(tree);
1576 if ( (ntype == if_stmt)
1577 || (ntype == while_stmt)
1578 || (ntype == for_stmt)
1579 || (ntype == try_stmt)
1580 || (ntype == with_stmt)
1581 || (ntype == funcdef)
1582 || (ntype == classdef)
1583 || (ntype == decorated))
1584 res = validate_node(tree);
1585 else {
1586 res = 0;
1587 PyErr_Format(parser_error,
1588 "Illegal compound statement type: %d.", TYPE(tree));
1589 }
1590 return (res);
1591 }
1592
1593 static int
1594 validate_yield_or_testlist(node *tree)
1595 {
1596 if (TYPE(tree) == yield_expr)
1597 return validate_yield_expr(tree);
1598 else
1599 return validate_testlist(tree);
1600 }
1601
1602 static int
1603 validate_expr_stmt(node *tree)
1604 {
1605 int j;
1606 int nch = NCH(tree);
1607 int res = (validate_ntype(tree, expr_stmt)
1608 && is_odd(nch)
1609 && validate_testlist(CHILD(tree, 0)));
1610
1611 if (res && nch == 3
1612 && TYPE(CHILD(tree, 1)) == augassign) {
1613 res = validate_numnodes(CHILD(tree, 1), 1, "augassign")
1614 && validate_yield_or_testlist(CHILD(tree, 2));
1615
1616 if (res) {
1617 char *s = STR(CHILD(CHILD(tree, 1), 0));
1618
1619 res = (strcmp(s, "+=") == 0
1620 || strcmp(s, "-=") == 0
1621 || strcmp(s, "*=") == 0
1622 || strcmp(s, "/=") == 0
1623 || strcmp(s, "//=") == 0
1624 || strcmp(s, "%=") == 0
1625 || strcmp(s, "&=") == 0
1626 || strcmp(s, "|=") == 0
1627 || strcmp(s, "^=") == 0
1628 || strcmp(s, "<<=") == 0
1629 || strcmp(s, ">>=") == 0
1630 || strcmp(s, "**=") == 0);
1631 if (!res)
1632 err_string("illegal augmented assignment operator");
1633 }
1634 }
1635 else {
1636 for (j = 1; res && (j < nch); j += 2)
1637 res = validate_equal(CHILD(tree, j))
1638 && validate_yield_or_testlist(CHILD(tree, j + 1));
1639 }
1640 return (res);
1641 }
1642
1643
1644 /* print_stmt:
1645 *
1646 * 'print' ( [ test (',' test)* [','] ]
1647 * | '>>' test [ (',' test)+ [','] ] )
1648 */
1649 static int
1650 validate_print_stmt(node *tree)
1651 {
1652 int nch = NCH(tree);
1653 int res = (validate_ntype(tree, print_stmt)
1654 && (nch > 0)
1655 && validate_name(CHILD(tree, 0), "print"));
1656
1657 if (res && nch > 1) {
1658 int sym = TYPE(CHILD(tree, 1));
1659 int i = 1;
1660 int allow_trailing_comma = 1;
1661
1662 if (sym == test)
1663 res = validate_test(CHILD(tree, i++));
1664 else {
1665 if (nch < 3)
1666 res = validate_numnodes(tree, 3, "print_stmt");
1667 else {
1668 res = (validate_ntype(CHILD(tree, i), RIGHTSHIFT)
1669 && validate_test(CHILD(tree, i+1)));
1670 i += 2;
1671 allow_trailing_comma = 0;
1672 }
1673 }
1674 if (res) {
1675 /* ... (',' test)* [','] */
1676 while (res && i+2 <= nch) {
1677 res = (validate_comma(CHILD(tree, i))
1678 && validate_test(CHILD(tree, i+1)));
1679 allow_trailing_comma = 1;
1680 i += 2;
1681 }
1682 if (res && !allow_trailing_comma)
1683 res = validate_numnodes(tree, i, "print_stmt");
1684 else if (res && i < nch)
1685 res = validate_comma(CHILD(tree, i));
1686 }
1687 }
1688 return (res);
1689 }
1690
1691
1692 static int
1693 validate_del_stmt(node *tree)
1694 {
1695 return (validate_numnodes(tree, 2, "del_stmt")
1696 && validate_name(CHILD(tree, 0), "del")
1697 && validate_exprlist(CHILD(tree, 1)));
1698 }
1699
1700
1701 static int
1702 validate_return_stmt(node *tree)
1703 {
1704 int nch = NCH(tree);
1705 int res = (validate_ntype(tree, return_stmt)
1706 && ((nch == 1) || (nch == 2))
1707 && validate_name(CHILD(tree, 0), "return"));
1708
1709 if (res && (nch == 2))
1710 res = validate_testlist(CHILD(tree, 1));
1711
1712 return (res);
1713 }
1714
1715
1716 static int
1717 validate_raise_stmt(node *tree)
1718 {
1719 int nch = NCH(tree);
1720 int res = (validate_ntype(tree, raise_stmt)
1721 && ((nch == 1) || (nch == 2) || (nch == 4) || (nch == 6)));
1722
1723 if (res) {
1724 res = validate_name(CHILD(tree, 0), "raise");
1725 if (res && (nch >= 2))
1726 res = validate_test(CHILD(tree, 1));
1727 if (res && nch > 2) {
1728 res = (validate_comma(CHILD(tree, 2))
1729 && validate_test(CHILD(tree, 3)));
1730 if (res && (nch > 4))
1731 res = (validate_comma(CHILD(tree, 4))
1732 && validate_test(CHILD(tree, 5)));
1733 }
1734 }
1735 else
1736 (void) validate_numnodes(tree, 2, "raise");
1737 if (res && (nch == 4))
1738 res = (validate_comma(CHILD(tree, 2))
1739 && validate_test(CHILD(tree, 3)));
1740
1741 return (res);
1742 }
1743
1744
1745 /* yield_expr: 'yield' [testlist]
1746 */
1747 static int
1748 validate_yield_expr(node *tree)
1749 {
1750 int nch = NCH(tree);
1751 int res = (validate_ntype(tree, yield_expr)
1752 && ((nch == 1) || (nch == 2))
1753 && validate_name(CHILD(tree, 0), "yield"));
1754
1755 if (res && (nch == 2))
1756 res = validate_testlist(CHILD(tree, 1));
1757
1758 return (res);
1759 }
1760
1761
1762 /* yield_stmt: yield_expr
1763 */
1764 static int
1765 validate_yield_stmt(node *tree)
1766 {
1767 return (validate_ntype(tree, yield_stmt)
1768 && validate_numnodes(tree, 1, "yield_stmt")
1769 && validate_yield_expr(CHILD(tree, 0)));
1770 }
1771
1772
1773 static int
1774 validate_import_as_name(node *tree)
1775 {
1776 int nch = NCH(tree);
1777 int ok = validate_ntype(tree, import_as_name);
1778
1779 if (ok) {
1780 if (nch == 1)
1781 ok = validate_name(CHILD(tree, 0), NULL);
1782 else if (nch == 3)
1783 ok = (validate_name(CHILD(tree, 0), NULL)
1784 && validate_name(CHILD(tree, 1), "as")
1785 && validate_name(CHILD(tree, 2), NULL));
1786 else
1787 ok = validate_numnodes(tree, 3, "import_as_name");
1788 }
1789 return ok;
1790 }
1791
1792
1793 /* dotted_name: NAME ("." NAME)*
1794 */
1795 static int
1796 validate_dotted_name(node *tree)
1797 {
1798 int nch = NCH(tree);
1799 int res = (validate_ntype(tree, dotted_name)
1800 && is_odd(nch)
1801 && validate_name(CHILD(tree, 0), NULL));
1802 int i;
1803
1804 for (i = 1; res && (i < nch); i += 2) {
1805 res = (validate_dot(CHILD(tree, i))
1806 && validate_name(CHILD(tree, i+1), NULL));
1807 }
1808 return res;
1809 }
1810
1811
1812 /* dotted_as_name: dotted_name [NAME NAME]
1813 */
1814 static int
1815 validate_dotted_as_name(node *tree)
1816 {
1817 int nch = NCH(tree);
1818 int res = validate_ntype(tree, dotted_as_name);
1819
1820 if (res) {
1821 if (nch == 1)
1822 res = validate_dotted_name(CHILD(tree, 0));
1823 else if (nch == 3)
1824 res = (validate_dotted_name(CHILD(tree, 0))
1825 && validate_name(CHILD(tree, 1), "as")
1826 && validate_name(CHILD(tree, 2), NULL));
1827 else {
1828 res = 0;
1829 err_string("illegal number of children for dotted_as_name");
1830 }
1831 }
1832 return res;
1833 }
1834
1835
1836 /* dotted_as_name (',' dotted_as_name)* */
1837 static int
1838 validate_dotted_as_names(node *tree)
1839 {
1840 int nch = NCH(tree);
1841 int res = is_odd(nch) && validate_dotted_as_name(CHILD(tree, 0));
1842 int i;
1843
1844 for (i = 1; res && (i < nch); i += 2)
1845 res = (validate_comma(CHILD(tree, i))
1846 && validate_dotted_as_name(CHILD(tree, i + 1)));
1847 return (res);
1848 }
1849
1850
1851 /* import_as_name (',' import_as_name)* [','] */
1852 static int
1853 validate_import_as_names(node *tree)
1854 {
1855 int nch = NCH(tree);
1856 int res = validate_import_as_name(CHILD(tree, 0));
1857 int i;
1858
1859 for (i = 1; res && (i + 1 < nch); i += 2)
1860 res = (validate_comma(CHILD(tree, i))
1861 && validate_import_as_name(CHILD(tree, i + 1)));
1862 return (res);
1863 }
1864
1865
1866 /* 'import' dotted_as_names */
1867 static int
1868 validate_import_name(node *tree)
1869 {
1870 return (validate_ntype(tree, import_name)
1871 && validate_numnodes(tree, 2, "import_name")
1872 && validate_name(CHILD(tree, 0), "import")
1873 && validate_dotted_as_names(CHILD(tree, 1)));
1874 }
1875
1876 /* Helper function to count the number of leading dots in
1877 * 'from ...module import name'
1878 */
1879 static int
1880 count_from_dots(node *tree)
1881 {
1882 int i;
1883 for (i = 1; i < NCH(tree); i++)
1884 if (TYPE(CHILD(tree, i)) != DOT)
1885 break;
1886 return i-1;
1887 }
1888
1889 /* import_from: ('from' ('.'* dotted_name | '.'+)
1890 * 'import' ('*' | '(' import_as_names ')' | import_as_names))
1891 */
1892 static int
1893 validate_import_from(node *tree)
1894 {
1895 int nch = NCH(tree);
1896 int ndots = count_from_dots(tree);
1897 int havename = (TYPE(CHILD(tree, ndots + 1)) == dotted_name);
1898 int offset = ndots + havename;
1899 int res = validate_ntype(tree, import_from)
1900 && (offset >= 1)
1901 && (nch >= 3 + offset)
1902 && validate_name(CHILD(tree, 0), "from")
1903 && (!havename || validate_dotted_name(CHILD(tree, ndots + 1)))
1904 && validate_name(CHILD(tree, offset + 1), "import");
1905
1906 if (res && TYPE(CHILD(tree, offset + 2)) == LPAR)
1907 res = ((nch == offset + 5)
1908 && validate_lparen(CHILD(tree, offset + 2))
1909 && validate_import_as_names(CHILD(tree, offset + 3))
1910 && validate_rparen(CHILD(tree, offset + 4)));
1911 else if (res && TYPE(CHILD(tree, offset + 2)) != STAR)
1912 res = validate_import_as_names(CHILD(tree, offset + 2));
1913 return (res);
1914 }
1915
1916
1917 /* import_stmt: import_name | import_from */
1918 static int
1919 validate_import_stmt(node *tree)
1920 {
1921 int nch = NCH(tree);
1922 int res = validate_numnodes(tree, 1, "import_stmt");
1923
1924 if (res) {
1925 int ntype = TYPE(CHILD(tree, 0));
1926
1927 if (ntype == import_name || ntype == import_from)
1928 res = validate_node(CHILD(tree, 0));
1929 else {
1930 res = 0;
1931 err_string("illegal import_stmt child type");
1932 }
1933 }
1934 else if (nch == 1) {
1935 res = 0;
1936 PyErr_Format(parser_error,
1937 "Unrecognized child node of import_stmt: %d.",
1938 TYPE(CHILD(tree, 0)));
1939 }
1940 return (res);
1941 }
1942
1943
1944
1945
1946 static int
1947 validate_global_stmt(node *tree)
1948 {
1949 int j;
1950 int nch = NCH(tree);
1951 int res = (validate_ntype(tree, global_stmt)
1952 && is_even(nch) && (nch >= 2));
1953
1954 if (!res && !PyErr_Occurred())
1955 err_string("illegal global statement");
1956
1957 if (res)
1958 res = (validate_name(CHILD(tree, 0), "global")
1959 && validate_ntype(CHILD(tree, 1), NAME));
1960 for (j = 2; res && (j < nch); j += 2)
1961 res = (validate_comma(CHILD(tree, j))
1962 && validate_ntype(CHILD(tree, j + 1), NAME));
1963
1964 return (res);
1965 }
1966
1967
1968 /* exec_stmt:
1969 *
1970 * 'exec' expr ['in' test [',' test]]
1971 */
1972 static int
1973 validate_exec_stmt(node *tree)
1974 {
1975 int nch = NCH(tree);
1976 int res = (validate_ntype(tree, exec_stmt)
1977 && ((nch == 2) || (nch == 4) || (nch == 6))
1978 && validate_name(CHILD(tree, 0), "exec")
1979 && validate_expr(CHILD(tree, 1)));
1980
1981 if (!res && !PyErr_Occurred())
1982 err_string("illegal exec statement");
1983 if (res && (nch > 2))
1984 res = (validate_name(CHILD(tree, 2), "in")
1985 && validate_test(CHILD(tree, 3)));
1986 if (res && (nch == 6))
1987 res = (validate_comma(CHILD(tree, 4))
1988 && validate_test(CHILD(tree, 5)));
1989
1990 return (res);
1991 }
1992
1993
1994 /* assert_stmt:
1995 *
1996 * 'assert' test [',' test]
1997 */
1998 static int
1999 validate_assert_stmt(node *tree)
2000 {
2001 int nch = NCH(tree);
2002 int res = (validate_ntype(tree, assert_stmt)
2003 && ((nch == 2) || (nch == 4))
2004 && (validate_name(CHILD(tree, 0), "assert"))
2005 && validate_test(CHILD(tree, 1)));
2006
2007 if (!res && !PyErr_Occurred())
2008 err_string("illegal assert statement");
2009 if (res && (nch > 2))
2010 res = (validate_comma(CHILD(tree, 2))
2011 && validate_test(CHILD(tree, 3)));
2012
2013 return (res);
2014 }
2015
2016
2017 static int
2018 validate_while(node *tree)
2019 {
2020 int nch = NCH(tree);
2021 int res = (validate_ntype(tree, while_stmt)
2022 && ((nch == 4) || (nch == 7))
2023 && validate_name(CHILD(tree, 0), "while")
2024 && validate_test(CHILD(tree, 1))
2025 && validate_colon(CHILD(tree, 2))
2026 && validate_suite(CHILD(tree, 3)));
2027
2028 if (res && (nch == 7))
2029 res = (validate_name(CHILD(tree, 4), "else")
2030 && validate_colon(CHILD(tree, 5))
2031 && validate_suite(CHILD(tree, 6)));
2032
2033 return (res);
2034 }
2035
2036
2037 static int
2038 validate_for(node *tree)
2039 {
2040 int nch = NCH(tree);
2041 int res = (validate_ntype(tree, for_stmt)
2042 && ((nch == 6) || (nch == 9))
2043 && validate_name(CHILD(tree, 0), "for")
2044 && validate_exprlist(CHILD(tree, 1))
2045 && validate_name(CHILD(tree, 2), "in")
2046 && validate_testlist(CHILD(tree, 3))
2047 && validate_colon(CHILD(tree, 4))
2048 && validate_suite(CHILD(tree, 5)));
2049
2050 if (res && (nch == 9))
2051 res = (validate_name(CHILD(tree, 6), "else")
2052 && validate_colon(CHILD(tree, 7))
2053 && validate_suite(CHILD(tree, 8)));
2054
2055 return (res);
2056 }
2057
2058
2059 /* try_stmt:
2060 * 'try' ':' suite (except_clause ':' suite)+ ['else' ':' suite]
2061 ['finally' ':' suite]
2062 * | 'try' ':' suite 'finally' ':' suite
2063 *
2064 */
2065 static int
2066 validate_try(node *tree)
2067 {
2068 int nch = NCH(tree);
2069 int pos = 3;
2070 int res = (validate_ntype(tree, try_stmt)
2071 && (nch >= 6) && ((nch % 3) == 0));
2072
2073 if (res)
2074 res = (validate_name(CHILD(tree, 0), "try")
2075 && validate_colon(CHILD(tree, 1))
2076 && validate_suite(CHILD(tree, 2))
2077 && validate_colon(CHILD(tree, nch - 2))
2078 && validate_suite(CHILD(tree, nch - 1)));
2079 else if (!PyErr_Occurred()) {
2080 const char* name = "except";
2081 if (TYPE(CHILD(tree, nch - 3)) != except_clause)
2082 name = STR(CHILD(tree, nch - 3));
2083
2084 PyErr_Format(parser_error,
2085 "Illegal number of children for try/%s node.", name);
2086 }
2087 /* Handle try/finally statement */
2088 if (res && (TYPE(CHILD(tree, pos)) == NAME) &&
2089 (strcmp(STR(CHILD(tree, pos)), "finally") == 0)) {
2090 res = (validate_numnodes(tree, 6, "try/finally")
2091 && validate_colon(CHILD(tree, 4))
2092 && validate_suite(CHILD(tree, 5)));
2093 return (res);
2094 }
2095 /* try/except statement: skip past except_clause sections */
2096 while (res && pos < nch && (TYPE(CHILD(tree, pos)) == except_clause)) {
2097 res = (validate_except_clause(CHILD(tree, pos))
2098 && validate_colon(CHILD(tree, pos + 1))
2099 && validate_suite(CHILD(tree, pos + 2)));
2100 pos += 3;
2101 }
2102 /* skip else clause */
2103 if (res && pos < nch && (TYPE(CHILD(tree, pos)) == NAME) &&
2104 (strcmp(STR(CHILD(tree, pos)), "else") == 0)) {
2105 res = (validate_colon(CHILD(tree, pos + 1))
2106 && validate_suite(CHILD(tree, pos + 2)));
2107 pos += 3;
2108 }
2109 if (res && pos < nch) {
2110 /* last clause must be a finally */
2111 res = (validate_name(CHILD(tree, pos), "finally")
2112 && validate_numnodes(tree, pos + 3, "try/except/finally")
2113 && validate_colon(CHILD(tree, pos + 1))
2114 && validate_suite(CHILD(tree, pos + 2)));
2115 }
2116 return (res);
2117 }
2118
2119
2120 static int
2121 validate_except_clause(node *tree)
2122 {
2123 int nch = NCH(tree);
2124 int res = (validate_ntype(tree, except_clause)
2125 && ((nch == 1) || (nch == 2) || (nch == 4))
2126 && validate_name(CHILD(tree, 0), "except"));
2127
2128 if (res && (nch > 1))
2129 res = validate_test(CHILD(tree, 1));
2130 if (res && (nch == 4)) {
2131 if (TYPE(CHILD(tree, 2)) == NAME)
2132 res = validate_name(CHILD(tree, 2), "as");
2133 else
2134 res = validate_comma(CHILD(tree, 2));
2135 res = res && validate_test(CHILD(tree, 3));
2136 }
2137 return (res);
2138 }
2139
2140
2141 static int
2142 validate_test(node *tree)
2143 {
2144 int nch = NCH(tree);
2145 int res = validate_ntype(tree, test) && is_odd(nch);
2146
2147 if (res && (TYPE(CHILD(tree, 0)) == lambdef))
2148 res = ((nch == 1)
2149 && validate_lambdef(CHILD(tree, 0)));
2150 else if (res) {
2151 res = validate_or_test(CHILD(tree, 0));
2152 res = (res && (nch == 1 || (nch == 5 &&
2153 validate_name(CHILD(tree, 1), "if") &&
2154 validate_or_test(CHILD(tree, 2)) &&
2155 validate_name(CHILD(tree, 3), "else") &&
2156 validate_test(CHILD(tree, 4)))));
2157 }
2158 return (res);
2159 }
2160
2161 static int
2162 validate_old_test(node *tree)
2163 {
2164 int nch = NCH(tree);
2165 int res = validate_ntype(tree, old_test) && (nch == 1);
2166
2167 if (res && (TYPE(CHILD(tree, 0)) == old_lambdef))
2168 res = (validate_old_lambdef(CHILD(tree, 0)));
2169 else if (res) {
2170 res = (validate_or_test(CHILD(tree, 0)));
2171 }
2172 return (res);
2173 }
2174
2175 static int
2176 validate_or_test(node *tree)
2177 {
2178 int nch = NCH(tree);
2179 int res = validate_ntype(tree, or_test) && is_odd(nch);
2180
2181 if (res) {
2182 int pos;
2183 res = validate_and_test(CHILD(tree, 0));
2184 for (pos = 1; res && (pos < nch); pos += 2)
2185 res = (validate_name(CHILD(tree, pos), "or")
2186 && validate_and_test(CHILD(tree, pos + 1)));
2187 }
2188 return (res);
2189 }
2190
2191
2192 static int
2193 validate_and_test(node *tree)
2194 {
2195 int pos;
2196 int nch = NCH(tree);
2197 int res = (validate_ntype(tree, and_test)
2198 && is_odd(nch)
2199 && validate_not_test(CHILD(tree, 0)));
2200
2201 for (pos = 1; res && (pos < nch); pos += 2)
2202 res = (validate_name(CHILD(tree, pos), "and")
2203 && validate_not_test(CHILD(tree, 0)));
2204
2205 return (res);
2206 }
2207
2208
2209 static int
2210 validate_not_test(node *tree)
2211 {
2212 int nch = NCH(tree);
2213 int res = validate_ntype(tree, not_test) && ((nch == 1) || (nch == 2));
2214
2215 if (res) {
2216 if (nch == 2)
2217 res = (validate_name(CHILD(tree, 0), "not")
2218 && validate_not_test(CHILD(tree, 1)));
2219 else if (nch == 1)
2220 res = validate_comparison(CHILD(tree, 0));
2221 }
2222 return (res);
2223 }
2224
2225
2226 static int
2227 validate_comparison(node *tree)
2228 {
2229 int pos;
2230 int nch = NCH(tree);
2231 int res = (validate_ntype(tree, comparison)
2232 && is_odd(nch)
2233 && validate_expr(CHILD(tree, 0)));
2234
2235 for (pos = 1; res && (pos < nch); pos += 2)
2236 res = (validate_comp_op(CHILD(tree, pos))
2237 && validate_expr(CHILD(tree, pos + 1)));
2238
2239 return (res);
2240 }
2241
2242
2243 static int
2244 validate_comp_op(node *tree)
2245 {
2246 int res = 0;
2247 int nch = NCH(tree);
2248
2249 if (!validate_ntype(tree, comp_op))
2250 return (0);
2251 if (nch == 1) {
2252 /*
2253 * Only child will be a terminal with a well-defined symbolic name
2254 * or a NAME with a string of either 'is' or 'in'
2255 */
2256 tree = CHILD(tree, 0);
2257 switch (TYPE(tree)) {
2258 case LESS:
2259 case GREATER:
2260 case EQEQUAL:
2261 case EQUAL:
2262 case LESSEQUAL:
2263 case GREATEREQUAL:
2264 case NOTEQUAL:
2265 res = 1;
2266 break;
2267 case NAME:
2268 res = ((strcmp(STR(tree), "in") == 0)
2269 || (strcmp(STR(tree), "is") == 0));
2270 if (!res) {
2271 PyErr_Format(parser_error,
2272 "illegal operator '%s'", STR(tree));
2273 }
2274 break;
2275 default:
2276 err_string("illegal comparison operator type");
2277 break;
2278 }
2279 }
2280 else if ((res = validate_numnodes(tree, 2, "comp_op")) != 0) {
2281 res = (validate_ntype(CHILD(tree, 0), NAME)
2282 && validate_ntype(CHILD(tree, 1), NAME)
2283 && (((strcmp(STR(CHILD(tree, 0)), "is") == 0)
2284 && (strcmp(STR(CHILD(tree, 1)), "not") == 0))
2285 || ((strcmp(STR(CHILD(tree, 0)), "not") == 0)
2286 && (strcmp(STR(CHILD(tree, 1)), "in") == 0))));
2287 if (!res && !PyErr_Occurred())
2288 err_string("unknown comparison operator");
2289 }
2290 return (res);
2291 }
2292
2293
2294 static int
2295 validate_expr(node *tree)
2296 {
2297 int j;
2298 int nch = NCH(tree);
2299 int res = (validate_ntype(tree, expr)
2300 && is_odd(nch)
2301 && validate_xor_expr(CHILD(tree, 0)));
2302
2303 for (j = 2; res && (j < nch); j += 2)
2304 res = (validate_xor_expr(CHILD(tree, j))
2305 && validate_vbar(CHILD(tree, j - 1)));
2306
2307 return (res);
2308 }
2309
2310
2311 static int
2312 validate_xor_expr(node *tree)
2313 {
2314 int j;
2315 int nch = NCH(tree);
2316 int res = (validate_ntype(tree, xor_expr)
2317 && is_odd(nch)
2318 && validate_and_expr(CHILD(tree, 0)));
2319
2320 for (j = 2; res && (j < nch); j += 2)
2321 res = (validate_circumflex(CHILD(tree, j - 1))
2322 && validate_and_expr(CHILD(tree, j)));
2323
2324 return (res);
2325 }
2326
2327
2328 static int
2329 validate_and_expr(node *tree)
2330 {
2331 int pos;
2332 int nch = NCH(tree);
2333 int res = (validate_ntype(tree, and_expr)
2334 && is_odd(nch)
2335 && validate_shift_expr(CHILD(tree, 0)));
2336
2337 for (pos = 1; res && (pos < nch); pos += 2)
2338 res = (validate_ampersand(CHILD(tree, pos))
2339 && validate_shift_expr(CHILD(tree, pos + 1)));
2340
2341 return (res);
2342 }
2343
2344
2345 static int
2346 validate_chain_two_ops(node *tree, int (*termvalid)(node *), int op1, int op2)
2347 {
2348 int pos = 1;
2349 int nch = NCH(tree);
2350 int res = (is_odd(nch)
2351 && (*termvalid)(CHILD(tree, 0)));
2352
2353 for ( ; res && (pos < nch); pos += 2) {
2354 if (TYPE(CHILD(tree, pos)) != op1)
2355 res = validate_ntype(CHILD(tree, pos), op2);
2356 if (res)
2357 res = (*termvalid)(CHILD(tree, pos + 1));
2358 }
2359 return (res);
2360 }
2361
2362
2363 static int
2364 validate_shift_expr(node *tree)
2365 {
2366 return (validate_ntype(tree, shift_expr)
2367 && validate_chain_two_ops(tree, validate_arith_expr,
2368 LEFTSHIFT, RIGHTSHIFT));
2369 }
2370
2371
2372 static int
2373 validate_arith_expr(node *tree)
2374 {
2375 return (validate_ntype(tree, arith_expr)
2376 && validate_chain_two_ops(tree, validate_term, PLUS, MINUS));
2377 }
2378
2379
2380 static int
2381 validate_term(node *tree)
2382 {
2383 int pos = 1;
2384 int nch = NCH(tree);
2385 int res = (validate_ntype(tree, term)
2386 && is_odd(nch)
2387 && validate_factor(CHILD(tree, 0)));
2388
2389 for ( ; res && (pos < nch); pos += 2)
2390 res = (((TYPE(CHILD(tree, pos)) == STAR)
2391 || (TYPE(CHILD(tree, pos)) == SLASH)
2392 || (TYPE(CHILD(tree, pos)) == DOUBLESLASH)
2393 || (TYPE(CHILD(tree, pos)) == PERCENT))
2394 && validate_factor(CHILD(tree, pos + 1)));
2395
2396 return (res);
2397 }
2398
2399
2400 /* factor:
2401 *
2402 * factor: ('+'|'-'|'~') factor | power
2403 */
2404 static int
2405 validate_factor(node *tree)
2406 {
2407 int nch = NCH(tree);
2408 int res = (validate_ntype(tree, factor)
2409 && (((nch == 2)
2410 && ((TYPE(CHILD(tree, 0)) == PLUS)
2411 || (TYPE(CHILD(tree, 0)) == MINUS)
2412 || (TYPE(CHILD(tree, 0)) == TILDE))
2413 && validate_factor(CHILD(tree, 1)))
2414 || ((nch == 1)
2415 && validate_power(CHILD(tree, 0)))));
2416 return (res);
2417 }
2418
2419
2420 /* power:
2421 *
2422 * power: atom trailer* ('**' factor)*
2423 */
2424 static int
2425 validate_power(node *tree)
2426 {
2427 int pos = 1;
2428 int nch = NCH(tree);
2429 int res = (validate_ntype(tree, power) && (nch >= 1)
2430 && validate_atom(CHILD(tree, 0)));
2431
2432 while (res && (pos < nch) && (TYPE(CHILD(tree, pos)) == trailer))
2433 res = validate_trailer(CHILD(tree, pos++));
2434 if (res && (pos < nch)) {
2435 if (!is_even(nch - pos)) {
2436 err_string("illegal number of nodes for 'power'");
2437 return (0);
2438 }
2439 for ( ; res && (pos < (nch - 1)); pos += 2)
2440 res = (validate_doublestar(CHILD(tree, pos))
2441 && validate_factor(CHILD(tree, pos + 1)));
2442 }
2443 return (res);
2444 }
2445
2446
2447 static int
2448 validate_atom(node *tree)
2449 {
2450 int pos;
2451 int nch = NCH(tree);
2452 int res = validate_ntype(tree, atom);
2453
2454 if (res && nch < 1)
2455 res = validate_numnodes(tree, nch+1, "atom");
2456 if (res) {
2457 switch (TYPE(CHILD(tree, 0))) {
2458 case LPAR:
2459 res = ((nch <= 3)
2460 && (validate_rparen(CHILD(tree, nch - 1))));
2461
2462 if (res && (nch == 3)) {
2463 if (TYPE(CHILD(tree, 1))==yield_expr)
2464 res = validate_yield_expr(CHILD(tree, 1));
2465 else
2466 res = validate_testlist_comp(CHILD(tree, 1));
2467 }
2468 break;
2469 case LSQB:
2470 if (nch == 2)
2471 res = validate_ntype(CHILD(tree, 1), RSQB);
2472 else if (nch == 3)
2473 res = (validate_listmaker(CHILD(tree, 1))
2474 && validate_ntype(CHILD(tree, 2), RSQB));
2475 else {
2476 res = 0;
2477 err_string("illegal list display atom");
2478 }
2479 break;
2480 case LBRACE:
2481 res = ((nch <= 3)
2482 && validate_ntype(CHILD(tree, nch - 1), RBRACE));
2483
2484 if (res && (nch == 3))
2485 res = validate_dictorsetmaker(CHILD(tree, 1));
2486 break;
2487 case BACKQUOTE:
2488 res = ((nch == 3)
2489 && validate_testlist1(CHILD(tree, 1))
2490 && validate_ntype(CHILD(tree, 2), BACKQUOTE));
2491 break;
2492 case NAME:
2493 case NUMBER:
2494 res = (nch == 1);
2495 break;
2496 case STRING:
2497 for (pos = 1; res && (pos < nch); ++pos)
2498 res = validate_ntype(CHILD(tree, pos), STRING);
2499 break;
2500 default:
2501 res = 0;
2502 break;
2503 }
2504 }
2505 return (res);
2506 }
2507
2508
2509 /* listmaker:
2510 * test ( list_for | (',' test)* [','] )
2511 */
2512 static int
2513 validate_listmaker(node *tree)
2514 {
2515 int nch = NCH(tree);
2516 int ok = nch;
2517
2518 if (nch == 0)
2519 err_string("missing child nodes of listmaker");
2520 else
2521 ok = validate_test(CHILD(tree, 0));
2522
2523 /*
2524 * list_for | (',' test)* [',']
2525 */
2526 if (nch == 2 && TYPE(CHILD(tree, 1)) == list_for)
2527 ok = validate_list_for(CHILD(tree, 1));
2528 else {
2529 /* (',' test)* [','] */
2530 int i = 1;
2531 while (ok && nch - i >= 2) {
2532 ok = (validate_comma(CHILD(tree, i))
2533 && validate_test(CHILD(tree, i+1)));
2534 i += 2;
2535 }
2536 if (ok && i == nch-1)
2537 ok = validate_comma(CHILD(tree, i));
2538 else if (i != nch) {
2539 ok = 0;
2540 err_string("illegal trailing nodes for listmaker");
2541 }
2542 }
2543 return ok;
2544 }
2545
2546 /* testlist_comp:
2547 * test ( comp_for | (',' test)* [','] )
2548 */
2549 static int
2550 validate_testlist_comp(node *tree)
2551 {
2552 int nch = NCH(tree);
2553 int ok = nch;
2554
2555 if (nch == 0)
2556 err_string("missing child nodes of testlist_comp");
2557 else {
2558 ok = validate_test(CHILD(tree, 0));
2559 }
2560
2561 /*
2562 * comp_for | (',' test)* [',']
2563 */
2564 if (nch == 2 && TYPE(CHILD(tree, 1)) == comp_for)
2565 ok = validate_comp_for(CHILD(tree, 1));
2566 else {
2567 /* (',' test)* [','] */
2568 int i = 1;
2569 while (ok && nch - i >= 2) {
2570 ok = (validate_comma(CHILD(tree, i))
2571 && validate_test(CHILD(tree, i+1)));
2572 i += 2;
2573 }
2574 if (ok && i == nch-1)
2575 ok = validate_comma(CHILD(tree, i));
2576 else if (i != nch) {
2577 ok = 0;
2578 err_string("illegal trailing nodes for testlist_comp");
2579 }
2580 }
2581 return ok;
2582 }
2583
2584 /* decorator:
2585 * '@' dotted_name [ '(' [arglist] ')' ] NEWLINE
2586 */
2587 static int
2588 validate_decorator(node *tree)
2589 {
2590 int ok;
2591 int nch = NCH(tree);
2592 ok = (validate_ntype(tree, decorator) &&
2593 (nch == 3 || nch == 5 || nch == 6) &&
2594 validate_at(CHILD(tree, 0)) &&
2595 validate_dotted_name(CHILD(tree, 1)) &&
2596 validate_newline(RCHILD(tree, -1)));
2597
2598 if (ok && nch != 3) {
2599 ok = (validate_lparen(CHILD(tree, 2)) &&
2600 validate_rparen(RCHILD(tree, -2)));
2601
2602 if (ok && nch == 6)
2603 ok = validate_arglist(CHILD(tree, 3));
2604 }
2605
2606 return ok;
2607 }
2608
2609 /* decorators:
2610 * decorator+
2611 */
2612 static int
2613 validate_decorators(node *tree)
2614 {
2615 int i, nch, ok;
2616 nch = NCH(tree);
2617 ok = validate_ntype(tree, decorators) && nch >= 1;
2618
2619 for (i = 0; ok && i < nch; ++i)
2620 ok = validate_decorator(CHILD(tree, i));
2621
2622 return ok;
2623 }
2624
2625 /* with_item:
2626 * test ['as' expr]
2627 */
2628 static int
2629 validate_with_item(node *tree)
2630 {
2631 int nch = NCH(tree);
2632 int ok = (validate_ntype(tree, with_item)
2633 && (nch == 1 || nch == 3)
2634 && validate_test(CHILD(tree, 0)));
2635 if (ok && nch == 3)
2636 ok = (validate_name(CHILD(tree, 1), "as")
2637 && validate_expr(CHILD(tree, 2)));
2638 return ok;
2639 }
2640
2641 /* with_stmt:
2642 * 0 1 ... -2 -1
2643 * 'with' with_item (',' with_item)* ':' suite
2644 */
2645 static int
2646 validate_with_stmt(node *tree)
2647 {
2648 int i;
2649 int nch = NCH(tree);
2650 int ok = (validate_ntype(tree, with_stmt)
2651 && (nch % 2 == 0)
2652 && validate_name(CHILD(tree, 0), "with")
2653 && validate_colon(RCHILD(tree, -2))
2654 && validate_suite(RCHILD(tree, -1)));
2655 for (i = 1; ok && i < nch - 2; i += 2)
2656 ok = validate_with_item(CHILD(tree, i));
2657 return ok;
2658 }
2659
2660 /* funcdef:
2661 *
2662 * -5 -4 -3 -2 -1
2663 * 'def' NAME parameters ':' suite
2664 */
2665 static int
2666 validate_funcdef(node *tree)
2667 {
2668 int nch = NCH(tree);
2669 int ok = (validate_ntype(tree, funcdef)
2670 && (nch == 5)
2671 && validate_name(RCHILD(tree, -5), "def")
2672 && validate_ntype(RCHILD(tree, -4), NAME)
2673 && validate_colon(RCHILD(tree, -2))
2674 && validate_parameters(RCHILD(tree, -3))
2675 && validate_suite(RCHILD(tree, -1)));
2676 return ok;
2677 }
2678
2679
2680 /* decorated
2681 * decorators (classdef | funcdef)
2682 */
2683 static int
2684 validate_decorated(node *tree)
2685 {
2686 int nch = NCH(tree);
2687 int ok = (validate_ntype(tree, decorated)
2688 && (nch == 2)
2689 && validate_decorators(RCHILD(tree, -2)));
2690 if (TYPE(RCHILD(tree, -1)) == funcdef)
2691 ok = ok && validate_funcdef(RCHILD(tree, -1));
2692 else
2693 ok = ok && validate_class(RCHILD(tree, -1));
2694 return ok;
2695 }
2696
2697 static int
2698 validate_lambdef(node *tree)
2699 {
2700 int nch = NCH(tree);
2701 int res = (validate_ntype(tree, lambdef)
2702 && ((nch == 3) || (nch == 4))
2703 && validate_name(CHILD(tree, 0), "lambda")
2704 && validate_colon(CHILD(tree, nch - 2))
2705 && validate_test(CHILD(tree, nch - 1)));
2706
2707 if (res && (nch == 4))
2708 res = validate_varargslist(CHILD(tree, 1));
2709 else if (!res && !PyErr_Occurred())
2710 (void) validate_numnodes(tree, 3, "lambdef");
2711
2712 return (res);
2713 }
2714
2715
2716 static int
2717 validate_old_lambdef(node *tree)
2718 {
2719 int nch = NCH(tree);
2720 int res = (validate_ntype(tree, old_lambdef)
2721 && ((nch == 3) || (nch == 4))
2722 && validate_name(CHILD(tree, 0), "lambda")
2723 && validate_colon(CHILD(tree, nch - 2))
2724 && validate_test(CHILD(tree, nch - 1)));
2725
2726 if (res && (nch == 4))
2727 res = validate_varargslist(CHILD(tree, 1));
2728 else if (!res && !PyErr_Occurred())
2729 (void) validate_numnodes(tree, 3, "old_lambdef");
2730
2731 return (res);
2732 }
2733
2734
2735 /* arglist:
2736 *
2737 * (argument ',')* (argument [','] | '*' test [',' '**' test] | '**' test)
2738 */
2739 static int
2740 validate_arglist(node *tree)
2741 {
2742 int nch = NCH(tree);
2743 int i = 0;
2744 int ok = 1;
2745
2746 if (nch <= 0)
2747 /* raise the right error from having an invalid number of children */
2748 return validate_numnodes(tree, nch + 1, "arglist");
2749
2750 if (nch > 1) {
2751 for (i=0; i<nch; i++) {
2752 if (TYPE(CHILD(tree, i)) == argument) {
2753 node *ch = CHILD(tree, i);
2754 if (NCH(ch) == 2 && TYPE(CHILD(ch, 1)) == comp_for) {
2755 err_string("need '(', ')' for generator expression");
2756 return 0;
2757 }
2758 }
2759 }
2760 }
2761
2762 while (ok && nch-i >= 2) {
2763 /* skip leading (argument ',') */
2764 ok = (validate_argument(CHILD(tree, i))
2765 && validate_comma(CHILD(tree, i+1)));
2766 if (ok)
2767 i += 2;
2768 else
2769 PyErr_Clear();
2770 }
2771 ok = 1;
2772 if (nch-i > 0) {
2773 /*
2774 * argument | '*' test [',' '**' test] | '**' test
2775 */
2776 int sym = TYPE(CHILD(tree, i));
2777
2778 if (sym == argument) {
2779 ok = validate_argument(CHILD(tree, i));
2780 if (ok && i+1 != nch) {
2781 err_string("illegal arglist specification"
2782 " (extra stuff on end)");
2783 ok = 0;
2784 }
2785 }
2786 else if (sym == STAR) {
2787 ok = validate_star(CHILD(tree, i));
2788 if (ok && (nch-i == 2))
2789 ok = validate_test(CHILD(tree, i+1));
2790 else if (ok && (nch-i == 5))
2791 ok = (validate_test(CHILD(tree, i+1))
2792 && validate_comma(CHILD(tree, i+2))
2793 && validate_doublestar(CHILD(tree, i+3))
2794 && validate_test(CHILD(tree, i+4)));
2795 else {
2796 err_string("illegal use of '*' in arglist");
2797 ok = 0;
2798 }
2799 }
2800 else if (sym == DOUBLESTAR) {
2801 if (nch-i == 2)
2802 ok = (validate_doublestar(CHILD(tree, i))
2803 && validate_test(CHILD(tree, i+1)));
2804 else {
2805 err_string("illegal use of '**' in arglist");
2806 ok = 0;
2807 }
2808 }
2809 else {
2810 err_string("illegal arglist specification");
2811 ok = 0;
2812 }
2813 }
2814 return (ok);
2815 }
2816
2817
2818
2819 /* argument:
2820 *
2821 * [test '='] test [comp_for]
2822 */
2823 static int
2824 validate_argument(node *tree)
2825 {
2826 int nch = NCH(tree);
2827 int res = (validate_ntype(tree, argument)
2828 && ((nch == 1) || (nch == 2) || (nch == 3))
2829 && validate_test(CHILD(tree, 0)));
2830
2831 if (res && (nch == 2))
2832 res = validate_comp_for(CHILD(tree, 1));
2833 else if (res && (nch == 3))
2834 res = (validate_equal(CHILD(tree, 1))
2835 && validate_test(CHILD(tree, 2)));
2836
2837 return (res);
2838 }
2839
2840
2841
2842 /* trailer:
2843 *
2844 * '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME
2845 */
2846 static int
2847 validate_trailer(node *tree)
2848 {
2849 int nch = NCH(tree);
2850 int res = validate_ntype(tree, trailer) && ((nch == 2) || (nch == 3));
2851
2852 if (res) {
2853 switch (TYPE(CHILD(tree, 0))) {
2854 case LPAR:
2855 res = validate_rparen(CHILD(tree, nch - 1));
2856 if (res && (nch == 3))
2857 res = validate_arglist(CHILD(tree, 1));
2858 break;
2859 case LSQB:
2860 res = (validate_numnodes(tree, 3, "trailer")
2861 && validate_subscriptlist(CHILD(tree, 1))
2862 && validate_ntype(CHILD(tree, 2), RSQB));
2863 break;
2864 case DOT:
2865 res = (validate_numnodes(tree, 2, "trailer")
2866 && validate_ntype(CHILD(tree, 1), NAME));
2867 break;
2868 default:
2869 res = 0;
2870 break;
2871 }
2872 }
2873 else {
2874 (void) validate_numnodes(tree, 2, "trailer");
2875 }
2876 return (res);
2877 }
2878
2879
2880 /* subscriptlist:
2881 *
2882 * subscript (',' subscript)* [',']
2883 */
2884 static int
2885 validate_subscriptlist(node *tree)
2886 {
2887 return (validate_repeating_list(tree, subscriptlist,
2888 validate_subscript, "subscriptlist"));
2889 }
2890
2891
2892 /* subscript:
2893 *
2894 * '.' '.' '.' | test | [test] ':' [test] [sliceop]
2895 */
2896 static int
2897 validate_subscript(node *tree)
2898 {
2899 int offset = 0;
2900 int nch = NCH(tree);
2901 int res = validate_ntype(tree, subscript) && (nch >= 1) && (nch <= 4);
2902
2903 if (!res) {
2904 if (!PyErr_Occurred())
2905 err_string("invalid number of arguments for subscript node");
2906 return (0);
2907 }
2908 if (TYPE(CHILD(tree, 0)) == DOT)
2909 /* take care of ('.' '.' '.') possibility */
2910 return (validate_numnodes(tree, 3, "subscript")
2911 && validate_dot(CHILD(tree, 0))
2912 && validate_dot(CHILD(tree, 1))
2913 && validate_dot(CHILD(tree, 2)));
2914 if (nch == 1) {
2915 if (TYPE(CHILD(tree, 0)) == test)
2916 res = validate_test(CHILD(tree, 0));
2917 else
2918 res = validate_colon(CHILD(tree, 0));
2919 return (res);
2920 }
2921 /* Must be [test] ':' [test] [sliceop],
2922 * but at least one of the optional components will
2923 * be present, but we don't know which yet.
2924 */
2925 if ((TYPE(CHILD(tree, 0)) != COLON) || (nch == 4)) {
2926 res = validate_test(CHILD(tree, 0));
2927 offset = 1;
2928 }
2929 if (res)
2930 res = validate_colon(CHILD(tree, offset));
2931 if (res) {
2932 int rem = nch - ++offset;
2933 if (rem) {
2934 if (TYPE(CHILD(tree, offset)) == test) {
2935 res = validate_test(CHILD(tree, offset));
2936 ++offset;
2937 --rem;
2938 }
2939 if (res && rem)
2940 res = validate_sliceop(CHILD(tree, offset));
2941 }
2942 }
2943 return (res);
2944 }
2945
2946
2947 static int
2948 validate_sliceop(node *tree)
2949 {
2950 int nch = NCH(tree);
2951 int res = ((nch == 1) || validate_numnodes(tree, 2, "sliceop"))
2952 && validate_ntype(tree, sliceop);
2953 if (!res && !PyErr_Occurred()) {
2954 res = validate_numnodes(tree, 1, "sliceop");
2955 }
2956 if (res)
2957 res = validate_colon(CHILD(tree, 0));
2958 if (res && (nch == 2))
2959 res = validate_test(CHILD(tree, 1));
2960
2961 return (res);
2962 }
2963
2964
2965 static int
2966 validate_exprlist(node *tree)
2967 {
2968 return (validate_repeating_list(tree, exprlist,
2969 validate_expr, "exprlist"));
2970 }
2971
2972
2973 /*
2974 * dictorsetmaker:
2975 *
2976 * (test ':' test (comp_for | (',' test ':' test)* [','])) |
2977 * (test (comp_for | (',' test)* [',']))
2978 */
2979 static int
2980 validate_dictorsetmaker(node *tree)
2981 {
2982 int nch = NCH(tree);
2983 int ok = validate_ntype(tree, dictorsetmaker);
2984 int i = 0;
2985 int check_trailing_comma = 0;
2986
2987 assert(nch > 0);
2988
2989 if (ok && (nch == 1 || TYPE(CHILD(tree, 1)) == COMMA)) {
2990 /* We got a set:
2991 * test (',' test)* [',']
2992 */
2993 ok = validate_test(CHILD(tree, i++));
2994 while (ok && nch - i >= 2) {
2995 ok = (validate_comma(CHILD(tree, i))
2996 && validate_test(CHILD(tree, i+1)));
2997 i += 2;
2998 }
2999 check_trailing_comma = 1;
3000 }
3001 else if (ok && TYPE(CHILD(tree, 1)) == comp_for) {
3002 /* We got a set comprehension:
3003 * test comp_for
3004 */
3005 ok = (validate_test(CHILD(tree, 0))
3006 && validate_comp_for(CHILD(tree, 1)));
3007 }
3008 else if (ok && NCH(tree) > 3 && TYPE(CHILD(tree, 3)) == comp_for) {
3009 /* We got a dict comprehension:
3010 * test ':' test comp_for
3011 */
3012 ok = (validate_test(CHILD(tree, 0))
3013 && validate_colon(CHILD(tree, 1))
3014 && validate_test(CHILD(tree, 2))
3015 && validate_comp_for(CHILD(tree, 3)));
3016 }
3017 else if (ok) {
3018 /* We got a dict:
3019 * test ':' test (',' test ':' test)* [',']
3020 */
3021 if (nch >= 3) {
3022 ok = (validate_test(CHILD(tree, i))
3023 && validate_colon(CHILD(tree, i+1))
3024 && validate_test(CHILD(tree, i+2)));
3025 i += 3;
3026 }
3027 else {
3028 ok = 0;
3029 err_string("illegal number of nodes for dictorsetmaker");
3030 }
3031
3032 while (ok && nch - i >= 4) {
3033 ok = (validate_comma(CHILD(tree, i))
3034 && validate_test(CHILD(tree, i+1))
3035 && validate_colon(CHILD(tree, i+2))
3036 && validate_test(CHILD(tree, i+3)));
3037 i += 4;
3038 }
3039 check_trailing_comma = 1;
3040 }
3041 if (ok && check_trailing_comma) {
3042 if (i == nch-1)
3043 ok = validate_comma(CHILD(tree, i));
3044 else if (i != nch) {
3045 ok = 0;
3046 err_string("illegal trailing nodes for dictorsetmaker");
3047 }
3048 }
3049
3050 return ok;
3051 }
3052
3053
3054 static int
3055 validate_eval_input(node *tree)
3056 {
3057 int pos;
3058 int nch = NCH(tree);
3059 int res = (validate_ntype(tree, eval_input)
3060 && (nch >= 2)
3061 && validate_testlist(CHILD(tree, 0))
3062 && validate_ntype(CHILD(tree, nch - 1), ENDMARKER));
3063
3064 for (pos = 1; res && (pos < (nch - 1)); ++pos)
3065 res = validate_ntype(CHILD(tree, pos), NEWLINE);
3066
3067 return (res);
3068 }
3069
3070
3071 static int
3072 validate_node(node *tree)
3073 {
3074 int nch = 0; /* num. children on current node */
3075 int res = 1; /* result value */
3076 node* next = 0; /* node to process after this one */
3077
3078 while (res && (tree != 0)) {
3079 nch = NCH(tree);
3080 next = 0;
3081 switch (TYPE(tree)) {
3082 /*
3083 * Definition nodes.
3084 */
3085 case funcdef:
3086 res = validate_funcdef(tree);
3087 break;
3088 case with_stmt:
3089 res = validate_with_stmt(tree);
3090 break;
3091 case classdef:
3092 res = validate_class(tree);
3093 break;
3094 case decorated:
3095 res = validate_decorated(tree);
3096 break;
3097 /*
3098 * "Trivial" parse tree nodes.
3099 * (Why did I call these trivial?)
3100 */
3101 case stmt:
3102 res = validate_stmt(tree);
3103 break;
3104 case small_stmt:
3105 /*
3106 * expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt
3107 * | import_stmt | global_stmt | exec_stmt | assert_stmt
3108 */
3109 res = validate_small_stmt(tree);
3110 break;
3111 case flow_stmt:
3112 res = (validate_numnodes(tree, 1, "flow_stmt")
3113 && ((TYPE(CHILD(tree, 0)) == break_stmt)
3114 || (TYPE(CHILD(tree, 0)) == continue_stmt)
3115 || (TYPE(CHILD(tree, 0)) == yield_stmt)
3116 || (TYPE(CHILD(tree, 0)) == return_stmt)
3117 || (TYPE(CHILD(tree, 0)) == raise_stmt)));
3118 if (res)
3119 next = CHILD(tree, 0);
3120 else if (nch == 1)
3121 err_string("illegal flow_stmt type");
3122 break;
3123 case yield_stmt:
3124 res = validate_yield_stmt(tree);
3125 break;
3126 /*
3127 * Compound statements.
3128 */
3129 case simple_stmt:
3130 res = validate_simple_stmt(tree);
3131 break;
3132 case compound_stmt:
3133 res = validate_compound_stmt(tree);
3134 break;
3135 /*
3136 * Fundamental statements.
3137 */
3138 case expr_stmt:
3139 res = validate_expr_stmt(tree);
3140 break;
3141 case print_stmt:
3142 res = validate_print_stmt(tree);
3143 break;
3144 case del_stmt:
3145 res = validate_del_stmt(tree);
3146 break;
3147 case pass_stmt:
3148 res = (validate_numnodes(tree, 1, "pass")
3149 && validate_name(CHILD(tree, 0), "pass"));
3150 break;
3151 case break_stmt:
3152 res = (validate_numnodes(tree, 1, "break")
3153 && validate_name(CHILD(tree, 0), "break"));
3154 break;
3155 case continue_stmt:
3156 res = (validate_numnodes(tree, 1, "continue")
3157 && validate_name(CHILD(tree, 0), "continue"));
3158 break;
3159 case return_stmt:
3160 res = validate_return_stmt(tree);
3161 break;
3162 case raise_stmt:
3163 res = validate_raise_stmt(tree);
3164 break;
3165 case import_stmt:
3166 res = validate_import_stmt(tree);
3167 break;
3168 case import_name:
3169 res = validate_import_name(tree);
3170 break;
3171 case import_from:
3172 res = validate_import_from(tree);
3173 break;
3174 case global_stmt:
3175 res = validate_global_stmt(tree);
3176 break;
3177 case exec_stmt:
3178 res = validate_exec_stmt(tree);
3179 break;
3180 case assert_stmt:
3181 res = validate_assert_stmt(tree);
3182 break;
3183 case if_stmt:
3184 res = validate_if(tree);
3185 break;
3186 case while_stmt:
3187 res = validate_while(tree);
3188 break;
3189 case for_stmt:
3190 res = validate_for(tree);
3191 break;
3192 case try_stmt:
3193 res = validate_try(tree);
3194 break;
3195 case suite:
3196 res = validate_suite(tree);
3197 break;
3198 /*
3199 * Expression nodes.
3200 */
3201 case testlist:
3202 res = validate_testlist(tree);
3203 break;
3204 case yield_expr:
3205 res = validate_yield_expr(tree);
3206 break;
3207 case testlist1:
3208 res = validate_testlist1(tree);
3209 break;
3210 case test:
3211 res = validate_test(tree);
3212 break;
3213 case and_test:
3214 res = validate_and_test(tree);
3215 break;
3216 case not_test:
3217 res = validate_not_test(tree);
3218 break;
3219 case comparison:
3220 res = validate_comparison(tree);
3221 break;
3222 case exprlist:
3223 res = validate_exprlist(tree);
3224 break;
3225 case comp_op:
3226 res = validate_comp_op(tree);
3227 break;
3228 case expr:
3229 res = validate_expr(tree);
3230 break;
3231 case xor_expr:
3232 res = validate_xor_expr(tree);
3233 break;
3234 case and_expr:
3235 res = validate_and_expr(tree);
3236 break;
3237 case shift_expr:
3238 res = validate_shift_expr(tree);
3239 break;
3240 case arith_expr:
3241 res = validate_arith_expr(tree);
3242 break;
3243 case term:
3244 res = validate_term(tree);
3245 break;
3246 case factor:
3247 res = validate_factor(tree);
3248 break;
3249 case power:
3250 res = validate_power(tree);
3251 break;
3252 case atom:
3253 res = validate_atom(tree);
3254 break;
3255
3256 default:
3257 /* Hopefully never reached! */
3258 err_string("unrecognized node type");
3259 res = 0;
3260 break;
3261 }
3262 tree = next;
3263 }
3264 return (res);
3265 }
3266
3267
3268 static int
3269 validate_expr_tree(node *tree)
3270 {
3271 int res = validate_eval_input(tree);
3272
3273 if (!res && !PyErr_Occurred())
3274 err_string("could not validate expression tuple");
3275
3276 return (res);
3277 }
3278
3279
3280 /* file_input:
3281 * (NEWLINE | stmt)* ENDMARKER
3282 */
3283 static int
3284 validate_file_input(node *tree)
3285 {
3286 int j;
3287 int nch = NCH(tree) - 1;
3288 int res = ((nch >= 0)
3289 && validate_ntype(CHILD(tree, nch), ENDMARKER));
3290
3291 for (j = 0; res && (j < nch); ++j) {
3292 if (TYPE(CHILD(tree, j)) == stmt)
3293 res = validate_stmt(CHILD(tree, j));
3294 else
3295 res = validate_newline(CHILD(tree, j));
3296 }
3297 /* This stays in to prevent any internal failures from getting to the
3298 * user. Hopefully, this won't be needed. If a user reports getting
3299 * this, we have some debugging to do.
3300 */
3301 if (!res && !PyErr_Occurred())
3302 err_string("VALIDATION FAILURE: report this to the maintainer!");
3303
3304 return (res);
3305 }
3306
3307 static int
3308 validate_encoding_decl(node *tree)
3309 {
3310 int nch = NCH(tree);
3311 int res = ((nch == 1)
3312 && validate_file_input(CHILD(tree, 0)));
3313
3314 if (!res && !PyErr_Occurred())
3315 err_string("Error Parsing encoding_decl");
3316
3317 return res;
3318 }
3319
3320 static PyObject*
3321 pickle_constructor = NULL;
3322
3323
3324 static PyObject*
3325 parser__pickler(PyObject *self, PyObject *args)
3326 {
3327 NOTE(ARGUNUSED(self))
3328 PyObject *result = NULL;
3329 PyObject *st = NULL;
3330 PyObject *empty_dict = NULL;
3331
3332 if (PyArg_ParseTuple(args, "O!:_pickler", &PyST_Type, &st)) {
3333 PyObject *newargs;
3334 PyObject *tuple;
3335
3336 if ((empty_dict = PyDict_New()) == NULL)
3337 goto finally;
3338 if ((newargs = Py_BuildValue("Oi", st, 1)) == NULL)
3339 goto finally;
3340 tuple = parser_st2tuple((PyST_Object*)NULL, newargs, empty_dict);
3341 if (tuple != NULL) {
3342 result = Py_BuildValue("O(O)", pickle_constructor, tuple);
3343 Py_DECREF(tuple);
3344 }
3345 Py_DECREF(empty_dict);
3346 Py_DECREF(newargs);
3347 }
3348 finally:
3349 Py_XDECREF(empty_dict);
3350
3351 return (result);
3352 }
3353
3354
3355 /* Functions exported by this module. Most of this should probably
3356 * be converted into an ST object with methods, but that is better
3357 * done directly in Python, allowing subclasses to be created directly.
3358 * We'd really have to write a wrapper around it all anyway to allow
3359 * inheritance.
3360 */
3361 static PyMethodDef parser_functions[] = {
3362 {"ast2tuple", (PyCFunction)parser_ast2tuple, PUBLIC_METHOD_TYPE,
3363 PyDoc_STR("Creates a tuple-tree representation of an ST.")},
3364 {"ast2list", (PyCFunction)parser_ast2list, PUBLIC_METHOD_TYPE,
3365 PyDoc_STR("Creates a list-tree representation of an ST.")},
3366 {"compileast", (PyCFunction)parser_compileast,PUBLIC_METHOD_TYPE,
3367 PyDoc_STR("Compiles an ST object into a code object.")},
3368 {"compilest", (PyCFunction)parser_compilest, PUBLIC_METHOD_TYPE,
3369 PyDoc_STR("Compiles an ST object into a code object.")},
3370 {"expr", (PyCFunction)parser_expr, PUBLIC_METHOD_TYPE,
3371 PyDoc_STR("Creates an ST object from an expression.")},
3372 {"isexpr", (PyCFunction)parser_isexpr, PUBLIC_METHOD_TYPE,
3373 PyDoc_STR("Determines if an ST object was created from an expression.")},
3374 {"issuite", (PyCFunction)parser_issuite, PUBLIC_METHOD_TYPE,
3375 PyDoc_STR("Determines if an ST object was created from a suite.")},
3376 {"suite", (PyCFunction)parser_suite, PUBLIC_METHOD_TYPE,
3377 PyDoc_STR("Creates an ST object from a suite.")},
3378 {"sequence2ast", (PyCFunction)parser_tuple2ast, PUBLIC_METHOD_TYPE,
3379 PyDoc_STR("Creates an ST object from a tree representation.")},
3380 {"sequence2st", (PyCFunction)parser_tuple2st, PUBLIC_METHOD_TYPE,
3381 PyDoc_STR("Creates an ST object from a tree representation.")},
3382 {"st2tuple", (PyCFunction)parser_st2tuple, PUBLIC_METHOD_TYPE,
3383 PyDoc_STR("Creates a tuple-tree representation of an ST.")},
3384 {"st2list", (PyCFunction)parser_st2list, PUBLIC_METHOD_TYPE,
3385 PyDoc_STR("Creates a list-tree representation of an ST.")},
3386 {"tuple2ast", (PyCFunction)parser_tuple2ast, PUBLIC_METHOD_TYPE,
3387 PyDoc_STR("Creates an ST object from a tree representation.")},
3388 {"tuple2st", (PyCFunction)parser_tuple2st, PUBLIC_METHOD_TYPE,
3389 PyDoc_STR("Creates an ST object from a tree representation.")},
3390
3391 /* private stuff: support pickle module */
3392 {"_pickler", (PyCFunction)parser__pickler, METH_VARARGS,
3393 PyDoc_STR("Returns the pickle magic to allow ST objects to be pickled.")},
3394
3395 {NULL, NULL, 0, NULL}
3396 };
3397
3398
3399 PyMODINIT_FUNC initparser(void); /* supply a prototype */
3400
3401 PyMODINIT_FUNC
3402 initparser(void)
3403 {
3404 PyObject *module, *copyreg;
3405
3406 Py_TYPE(&PyST_Type) = &PyType_Type;
3407 module = Py_InitModule("parser", parser_functions);
3408 if (module == NULL)
3409 return;
3410
3411 if (parser_error == 0)
3412 parser_error = PyErr_NewException("parser.ParserError", NULL, NULL);
3413
3414 if (parser_error == 0)
3415 /* caller will check PyErr_Occurred() */
3416 return;
3417 /* CAUTION: The code next used to skip bumping the refcount on
3418 * parser_error. That's a disaster if initparser() gets called more
3419 * than once. By incref'ing, we ensure that each module dict that
3420 * gets created owns its reference to the shared parser_error object,
3421 * and the file static parser_error vrbl owns a reference too.
3422 */
3423 Py_INCREF(parser_error);
3424 if (PyModule_AddObject(module, "ParserError", parser_error) != 0)
3425 return;
3426
3427 Py_INCREF(&PyST_Type);
3428 PyModule_AddObject(module, "ASTType", (PyObject*)&PyST_Type);
3429 Py_INCREF(&PyST_Type);
3430 PyModule_AddObject(module, "STType", (PyObject*)&PyST_Type);
3431
3432 PyModule_AddStringConstant(module, "__copyright__",
3433 parser_copyright_string);
3434 PyModule_AddStringConstant(module, "__doc__",
3435 parser_doc_string);
3436 PyModule_AddStringConstant(module, "__version__",
3437 parser_version_string);
3438
3439 /* Register to support pickling.
3440 * If this fails, the import of this module will fail because an
3441 * exception will be raised here; should we clear the exception?
3442 */
3443 copyreg = PyImport_ImportModuleNoBlock("copy_reg");
3444 if (copyreg != NULL) {
3445 PyObject *func, *pickler;
3446
3447 func = PyObject_GetAttrString(copyreg, "pickle");
3448 pickle_constructor = PyObject_GetAttrString(module, "sequence2st");
3449 pickler = PyObject_GetAttrString(module, "_pickler");
3450 Py_XINCREF(pickle_constructor);
3451 if ((func != NULL) && (pickle_constructor != NULL)
3452 && (pickler != NULL)) {
3453 PyObject *res;
3454
3455 res = PyObject_CallFunctionObjArgs(func, &PyST_Type, pickler,
3456 pickle_constructor, NULL);
3457 Py_XDECREF(res);
3458 }
3459 Py_XDECREF(func);
3460 Py_XDECREF(pickle_constructor);
3461 Py_XDECREF(pickler);
3462 Py_DECREF(copyreg);
3463 }
3464 }