1
2 /* Tokenizer implementation */
3
4 #include "Python.h"
5 #include "pgenheaders.h"
6
7 #include <ctype.h>
8 #include <assert.h>
9
10 #include "tokenizer.h"
11 #include "errcode.h"
12
13 #ifndef PGEN
14 #include "unicodeobject.h"
15 #include "bytesobject.h"
16 #include "fileobject.h"
17 #include "codecs.h"
18 #include "abstract.h"
19 #endif /* PGEN */
20
21 /* Alternate tab spacing */
22 #define ALTTABSIZE 1
23
24 #define is_potential_identifier_start(c) (\
25 (c >= 'a' && c <= 'z')\
26 || (c >= 'A' && c <= 'Z')\
27 || c == '_'\
28 || (c >= 128))
29
30 #define is_potential_identifier_char(c) (\
31 (c >= 'a' && c <= 'z')\
32 || (c >= 'A' && c <= 'Z')\
33 || (c >= '0' && c <= '9')\
34 || c == '_'\
35 || (c >= 128))
36
37 extern char *PyOS_Readline(FILE *, FILE *, const char *);
38 /* Return malloc'ed string including trailing \n;
39 empty malloc'ed string for EOF;
40 NULL if interrupted */
41
42 /* Don't ever change this -- it would break the portability of Python code */
43 #define TABSIZE 8
44
45 /* Forward */
46 static struct tok_state *tok_new(void);
47 static int tok_nextc(struct tok_state *tok);
48 static void tok_backup(struct tok_state *tok, int c);
49
50
51 /* Token names */
52
53 const char *_PyParser_TokenNames[] = {
54 "ENDMARKER",
55 "NAME",
56 "NUMBER",
57 "STRING",
58 "NEWLINE",
59 "INDENT",
60 "DEDENT",
61 "LPAR",
62 "RPAR",
63 "LSQB",
64 "RSQB",
65 "COLON",
66 "COMMA",
67 "SEMI",
68 "PLUS",
69 "MINUS",
70 "STAR",
71 "SLASH",
72 "VBAR",
73 "AMPER",
74 "LESS",
75 "GREATER",
76 "EQUAL",
77 "DOT",
78 "PERCENT",
79 "LBRACE",
80 "RBRACE",
81 "EQEQUAL",
82 "NOTEQUAL",
83 "LESSEQUAL",
84 "GREATEREQUAL",
85 "TILDE",
86 "CIRCUMFLEX",
87 "LEFTSHIFT",
88 "RIGHTSHIFT",
89 "DOUBLESTAR",
90 "PLUSEQUAL",
91 "MINEQUAL",
92 "STAREQUAL",
93 "SLASHEQUAL",
94 "PERCENTEQUAL",
95 "AMPEREQUAL",
96 "VBAREQUAL",
97 "CIRCUMFLEXEQUAL",
98 "LEFTSHIFTEQUAL",
99 "RIGHTSHIFTEQUAL",
100 "DOUBLESTAREQUAL",
101 "DOUBLESLASH",
102 "DOUBLESLASHEQUAL",
103 "AT",
104 "ATEQUAL",
105 "RARROW",
106 "ELLIPSIS",
107 /* This table must match the #defines in token.h! */
108 "OP",
109 "<ERRORTOKEN>",
110 "COMMENT",
111 "NL",
112 "ENCODING",
113 "<N_TOKENS>"
114 };
115
116
117 /* Create and initialize a new tok_state structure */
118
119 static struct tok_state *
tok_new(void)120 tok_new(void)
121 {
122 struct tok_state *tok = (struct tok_state *)PyMem_MALLOC(
123 sizeof(struct tok_state));
124 if (tok == NULL)
125 return NULL;
126 tok->buf = tok->cur = tok->end = tok->inp = tok->start = NULL;
127 tok->done = E_OK;
128 tok->fp = NULL;
129 tok->input = NULL;
130 tok->tabsize = TABSIZE;
131 tok->indent = 0;
132 tok->indstack[0] = 0;
133
134 tok->atbol = 1;
135 tok->pendin = 0;
136 tok->prompt = tok->nextprompt = NULL;
137 tok->lineno = 0;
138 tok->level = 0;
139 tok->altindstack[0] = 0;
140 tok->decoding_state = STATE_INIT;
141 tok->decoding_erred = 0;
142 tok->read_coding_spec = 0;
143 tok->enc = NULL;
144 tok->encoding = NULL;
145 tok->cont_line = 0;
146 #ifndef PGEN
147 tok->filename = NULL;
148 tok->decoding_readline = NULL;
149 tok->decoding_buffer = NULL;
150 #endif
151
152 return tok;
153 }
154
155 static char *
new_string(const char * s,Py_ssize_t len,struct tok_state * tok)156 new_string(const char *s, Py_ssize_t len, struct tok_state *tok)
157 {
158 char* result = (char *)PyMem_MALLOC(len + 1);
159 if (!result) {
160 tok->done = E_NOMEM;
161 return NULL;
162 }
163 memcpy(result, s, len);
164 result[len] = '\0';
165 return result;
166 }
167
168 #ifdef PGEN
169
170 static char *
decoding_fgets(char * s,int size,struct tok_state * tok)171 decoding_fgets(char *s, int size, struct tok_state *tok)
172 {
173 return fgets(s, size, tok->fp);
174 }
175
176 static int
decoding_feof(struct tok_state * tok)177 decoding_feof(struct tok_state *tok)
178 {
179 return feof(tok->fp);
180 }
181
182 static char *
decode_str(const char * str,int exec_input,struct tok_state * tok)183 decode_str(const char *str, int exec_input, struct tok_state *tok)
184 {
185 return new_string(str, strlen(str), tok);
186 }
187
188 #else /* PGEN */
189
190 static char *
error_ret(struct tok_state * tok)191 error_ret(struct tok_state *tok) /* XXX */
192 {
193 tok->decoding_erred = 1;
194 if (tok->fp != NULL && tok->buf != NULL) /* see PyTokenizer_Free */
195 PyMem_FREE(tok->buf);
196 tok->buf = tok->cur = tok->end = tok->inp = tok->start = NULL;
197 tok->done = E_DECODE;
198 return NULL; /* as if it were EOF */
199 }
200
201
202 static const char *
get_normal_name(const char * s)203 get_normal_name(const char *s) /* for utf-8 and latin-1 */
204 {
205 char buf[13];
206 int i;
207 for (i = 0; i < 12; i++) {
208 int c = s[i];
209 if (c == '\0')
210 break;
211 else if (c == '_')
212 buf[i] = '-';
213 else
214 buf[i] = tolower(c);
215 }
216 buf[i] = '\0';
217 if (strcmp(buf, "utf-8") == 0 ||
218 strncmp(buf, "utf-8-", 6) == 0)
219 return "utf-8";
220 else if (strcmp(buf, "latin-1") == 0 ||
221 strcmp(buf, "iso-8859-1") == 0 ||
222 strcmp(buf, "iso-latin-1") == 0 ||
223 strncmp(buf, "latin-1-", 8) == 0 ||
224 strncmp(buf, "iso-8859-1-", 11) == 0 ||
225 strncmp(buf, "iso-latin-1-", 12) == 0)
226 return "iso-8859-1";
227 else
228 return s;
229 }
230
231 /* Return the coding spec in S, or NULL if none is found. */
232
233 static int
get_coding_spec(const char * s,char ** spec,Py_ssize_t size,struct tok_state * tok)234 get_coding_spec(const char *s, char **spec, Py_ssize_t size, struct tok_state *tok)
235 {
236 Py_ssize_t i;
237 *spec = NULL;
238 /* Coding spec must be in a comment, and that comment must be
239 * the only statement on the source code line. */
240 for (i = 0; i < size - 6; i++) {
241 if (s[i] == '#')
242 break;
243 if (s[i] != ' ' && s[i] != '\t' && s[i] != '\014')
244 return 1;
245 }
246 for (; i < size - 6; i++) { /* XXX inefficient search */
247 const char* t = s + i;
248 if (strncmp(t, "coding", 6) == 0) {
249 const char* begin = NULL;
250 t += 6;
251 if (t[0] != ':' && t[0] != '=')
252 continue;
253 do {
254 t++;
255 } while (t[0] == '\x20' || t[0] == '\t');
256
257 begin = t;
258 while (Py_ISALNUM(t[0]) ||
259 t[0] == '-' || t[0] == '_' || t[0] == '.')
260 t++;
261
262 if (begin < t) {
263 char* r = new_string(begin, t - begin, tok);
264 const char* q;
265 if (!r)
266 return 0;
267 q = get_normal_name(r);
268 if (r != q) {
269 PyMem_FREE(r);
270 r = new_string(q, strlen(q), tok);
271 if (!r)
272 return 0;
273 }
274 *spec = r;
275 break;
276 }
277 }
278 }
279 return 1;
280 }
281
282 /* Check whether the line contains a coding spec. If it does,
283 invoke the set_readline function for the new encoding.
284 This function receives the tok_state and the new encoding.
285 Return 1 on success, 0 on failure. */
286
287 static int
check_coding_spec(const char * line,Py_ssize_t size,struct tok_state * tok,int set_readline (struct tok_state *,const char *))288 check_coding_spec(const char* line, Py_ssize_t size, struct tok_state *tok,
289 int set_readline(struct tok_state *, const char *))
290 {
291 char *cs;
292 int r = 1;
293
294 if (tok->cont_line) {
295 /* It's a continuation line, so it can't be a coding spec. */
296 tok->read_coding_spec = 1;
297 return 1;
298 }
299 if (!get_coding_spec(line, &cs, size, tok))
300 return 0;
301 if (!cs) {
302 Py_ssize_t i;
303 for (i = 0; i < size; i++) {
304 if (line[i] == '#' || line[i] == '\n' || line[i] == '\r')
305 break;
306 if (line[i] != ' ' && line[i] != '\t' && line[i] != '\014') {
307 /* Stop checking coding spec after a line containing
308 * anything except a comment. */
309 tok->read_coding_spec = 1;
310 break;
311 }
312 }
313 return 1;
314 }
315 tok->read_coding_spec = 1;
316 if (tok->encoding == NULL) {
317 assert(tok->decoding_state == STATE_RAW);
318 if (strcmp(cs, "utf-8") == 0) {
319 tok->encoding = cs;
320 } else {
321 r = set_readline(tok, cs);
322 if (r) {
323 tok->encoding = cs;
324 tok->decoding_state = STATE_NORMAL;
325 }
326 else {
327 PyErr_Format(PyExc_SyntaxError,
328 "encoding problem: %s", cs);
329 PyMem_FREE(cs);
330 }
331 }
332 } else { /* then, compare cs with BOM */
333 r = (strcmp(tok->encoding, cs) == 0);
334 if (!r)
335 PyErr_Format(PyExc_SyntaxError,
336 "encoding problem: %s with BOM", cs);
337 PyMem_FREE(cs);
338 }
339 return r;
340 }
341
342 /* See whether the file starts with a BOM. If it does,
343 invoke the set_readline function with the new encoding.
344 Return 1 on success, 0 on failure. */
345
346 static int
check_bom(int get_char (struct tok_state *),void unget_char (int,struct tok_state *),int set_readline (struct tok_state *,const char *),struct tok_state * tok)347 check_bom(int get_char(struct tok_state *),
348 void unget_char(int, struct tok_state *),
349 int set_readline(struct tok_state *, const char *),
350 struct tok_state *tok)
351 {
352 int ch1, ch2, ch3;
353 ch1 = get_char(tok);
354 tok->decoding_state = STATE_RAW;
355 if (ch1 == EOF) {
356 return 1;
357 } else if (ch1 == 0xEF) {
358 ch2 = get_char(tok);
359 if (ch2 != 0xBB) {
360 unget_char(ch2, tok);
361 unget_char(ch1, tok);
362 return 1;
363 }
364 ch3 = get_char(tok);
365 if (ch3 != 0xBF) {
366 unget_char(ch3, tok);
367 unget_char(ch2, tok);
368 unget_char(ch1, tok);
369 return 1;
370 }
371 #if 0
372 /* Disable support for UTF-16 BOMs until a decision
373 is made whether this needs to be supported. */
374 } else if (ch1 == 0xFE) {
375 ch2 = get_char(tok);
376 if (ch2 != 0xFF) {
377 unget_char(ch2, tok);
378 unget_char(ch1, tok);
379 return 1;
380 }
381 if (!set_readline(tok, "utf-16-be"))
382 return 0;
383 tok->decoding_state = STATE_NORMAL;
384 } else if (ch1 == 0xFF) {
385 ch2 = get_char(tok);
386 if (ch2 != 0xFE) {
387 unget_char(ch2, tok);
388 unget_char(ch1, tok);
389 return 1;
390 }
391 if (!set_readline(tok, "utf-16-le"))
392 return 0;
393 tok->decoding_state = STATE_NORMAL;
394 #endif
395 } else {
396 unget_char(ch1, tok);
397 return 1;
398 }
399 if (tok->encoding != NULL)
400 PyMem_FREE(tok->encoding);
401 tok->encoding = new_string("utf-8", 5, tok);
402 if (!tok->encoding)
403 return 0;
404 /* No need to set_readline: input is already utf-8 */
405 return 1;
406 }
407
408 /* Read a line of text from TOK into S, using the stream in TOK.
409 Return NULL on failure, else S.
410
411 On entry, tok->decoding_buffer will be one of:
412 1) NULL: need to call tok->decoding_readline to get a new line
413 2) PyUnicodeObject *: decoding_feof has called tok->decoding_readline and
414 stored the result in tok->decoding_buffer
415 3) PyByteArrayObject *: previous call to fp_readl did not have enough room
416 (in the s buffer) to copy entire contents of the line read
417 by tok->decoding_readline. tok->decoding_buffer has the overflow.
418 In this case, fp_readl is called in a loop (with an expanded buffer)
419 until the buffer ends with a '\n' (or until the end of the file is
420 reached): see tok_nextc and its calls to decoding_fgets.
421 */
422
423 static char *
fp_readl(char * s,int size,struct tok_state * tok)424 fp_readl(char *s, int size, struct tok_state *tok)
425 {
426 PyObject* bufobj;
427 const char *buf;
428 Py_ssize_t buflen;
429
430 /* Ask for one less byte so we can terminate it */
431 assert(size > 0);
432 size--;
433
434 if (tok->decoding_buffer) {
435 bufobj = tok->decoding_buffer;
436 Py_INCREF(bufobj);
437 }
438 else
439 {
440 bufobj = _PyObject_CallNoArg(tok->decoding_readline);
441 if (bufobj == NULL)
442 goto error;
443 }
444 if (PyUnicode_CheckExact(bufobj))
445 {
446 buf = PyUnicode_AsUTF8AndSize(bufobj, &buflen);
447 if (buf == NULL) {
448 goto error;
449 }
450 }
451 else
452 {
453 buf = PyByteArray_AsString(bufobj);
454 if (buf == NULL) {
455 goto error;
456 }
457 buflen = PyByteArray_GET_SIZE(bufobj);
458 }
459
460 Py_XDECREF(tok->decoding_buffer);
461 if (buflen > size) {
462 /* Too many chars, the rest goes into tok->decoding_buffer */
463 tok->decoding_buffer = PyByteArray_FromStringAndSize(buf+size,
464 buflen-size);
465 if (tok->decoding_buffer == NULL)
466 goto error;
467 buflen = size;
468 }
469 else
470 tok->decoding_buffer = NULL;
471
472 memcpy(s, buf, buflen);
473 s[buflen] = '\0';
474 if (buflen == 0) /* EOF */
475 s = NULL;
476 Py_DECREF(bufobj);
477 return s;
478
479 error:
480 Py_XDECREF(bufobj);
481 return error_ret(tok);
482 }
483
484 /* Set the readline function for TOK to a StreamReader's
485 readline function. The StreamReader is named ENC.
486
487 This function is called from check_bom and check_coding_spec.
488
489 ENC is usually identical to the future value of tok->encoding,
490 except for the (currently unsupported) case of UTF-16.
491
492 Return 1 on success, 0 on failure. */
493
494 static int
fp_setreadl(struct tok_state * tok,const char * enc)495 fp_setreadl(struct tok_state *tok, const char* enc)
496 {
497 PyObject *readline, *io, *stream;
498 _Py_IDENTIFIER(open);
499 _Py_IDENTIFIER(readline);
500 int fd;
501 long pos;
502
503 fd = fileno(tok->fp);
504 /* Due to buffering the file offset for fd can be different from the file
505 * position of tok->fp. If tok->fp was opened in text mode on Windows,
506 * its file position counts CRLF as one char and can't be directly mapped
507 * to the file offset for fd. Instead we step back one byte and read to
508 * the end of line.*/
509 pos = ftell(tok->fp);
510 if (pos == -1 ||
511 lseek(fd, (off_t)(pos > 0 ? pos - 1 : pos), SEEK_SET) == (off_t)-1) {
512 PyErr_SetFromErrnoWithFilename(PyExc_OSError, NULL);
513 return 0;
514 }
515
516 io = PyImport_ImportModuleNoBlock("io");
517 if (io == NULL)
518 return 0;
519
520 stream = _PyObject_CallMethodId(io, &PyId_open, "isisOOO",
521 fd, "r", -1, enc, Py_None, Py_None, Py_False);
522 Py_DECREF(io);
523 if (stream == NULL)
524 return 0;
525
526 readline = _PyObject_GetAttrId(stream, &PyId_readline);
527 Py_DECREF(stream);
528 if (readline == NULL)
529 return 0;
530 Py_XSETREF(tok->decoding_readline, readline);
531
532 if (pos > 0) {
533 PyObject *bufobj = _PyObject_CallNoArg(readline);
534 if (bufobj == NULL)
535 return 0;
536 Py_DECREF(bufobj);
537 }
538
539 return 1;
540 }
541
542 /* Fetch the next byte from TOK. */
543
fp_getc(struct tok_state * tok)544 static int fp_getc(struct tok_state *tok) {
545 return getc(tok->fp);
546 }
547
548 /* Unfetch the last byte back into TOK. */
549
fp_ungetc(int c,struct tok_state * tok)550 static void fp_ungetc(int c, struct tok_state *tok) {
551 ungetc(c, tok->fp);
552 }
553
554 /* Check whether the characters at s start a valid
555 UTF-8 sequence. Return the number of characters forming
556 the sequence if yes, 0 if not. */
valid_utf8(const unsigned char * s)557 static int valid_utf8(const unsigned char* s)
558 {
559 int expected = 0;
560 int length;
561 if (*s < 0x80)
562 /* single-byte code */
563 return 1;
564 if (*s < 0xc0)
565 /* following byte */
566 return 0;
567 if (*s < 0xE0)
568 expected = 1;
569 else if (*s < 0xF0)
570 expected = 2;
571 else if (*s < 0xF8)
572 expected = 3;
573 else
574 return 0;
575 length = expected + 1;
576 for (; expected; expected--)
577 if (s[expected] < 0x80 || s[expected] >= 0xC0)
578 return 0;
579 return length;
580 }
581
582 /* Read a line of input from TOK. Determine encoding
583 if necessary. */
584
585 static char *
decoding_fgets(char * s,int size,struct tok_state * tok)586 decoding_fgets(char *s, int size, struct tok_state *tok)
587 {
588 char *line = NULL;
589 int badchar = 0;
590 for (;;) {
591 if (tok->decoding_state == STATE_NORMAL) {
592 /* We already have a codec associated with
593 this input. */
594 line = fp_readl(s, size, tok);
595 break;
596 } else if (tok->decoding_state == STATE_RAW) {
597 /* We want a 'raw' read. */
598 line = Py_UniversalNewlineFgets(s, size,
599 tok->fp, NULL);
600 break;
601 } else {
602 /* We have not yet determined the encoding.
603 If an encoding is found, use the file-pointer
604 reader functions from now on. */
605 if (!check_bom(fp_getc, fp_ungetc, fp_setreadl, tok))
606 return error_ret(tok);
607 assert(tok->decoding_state != STATE_INIT);
608 }
609 }
610 if (line != NULL && tok->lineno < 2 && !tok->read_coding_spec) {
611 if (!check_coding_spec(line, strlen(line), tok, fp_setreadl)) {
612 return error_ret(tok);
613 }
614 }
615 #ifndef PGEN
616 /* The default encoding is UTF-8, so make sure we don't have any
617 non-UTF-8 sequences in it. */
618 if (line && !tok->encoding) {
619 unsigned char *c;
620 int length;
621 for (c = (unsigned char *)line; *c; c += length)
622 if (!(length = valid_utf8(c))) {
623 badchar = *c;
624 break;
625 }
626 }
627 if (badchar) {
628 /* Need to add 1 to the line number, since this line
629 has not been counted, yet. */
630 PyErr_Format(PyExc_SyntaxError,
631 "Non-UTF-8 code starting with '\\x%.2x' "
632 "in file %U on line %i, "
633 "but no encoding declared; "
634 "see http://python.org/dev/peps/pep-0263/ for details",
635 badchar, tok->filename, tok->lineno + 1);
636 return error_ret(tok);
637 }
638 #endif
639 return line;
640 }
641
642 static int
decoding_feof(struct tok_state * tok)643 decoding_feof(struct tok_state *tok)
644 {
645 if (tok->decoding_state != STATE_NORMAL) {
646 return feof(tok->fp);
647 } else {
648 PyObject* buf = tok->decoding_buffer;
649 if (buf == NULL) {
650 buf = _PyObject_CallNoArg(tok->decoding_readline);
651 if (buf == NULL) {
652 error_ret(tok);
653 return 1;
654 } else {
655 tok->decoding_buffer = buf;
656 }
657 }
658 return PyObject_Length(buf) == 0;
659 }
660 }
661
662 /* Fetch a byte from TOK, using the string buffer. */
663
664 static int
buf_getc(struct tok_state * tok)665 buf_getc(struct tok_state *tok) {
666 return Py_CHARMASK(*tok->str++);
667 }
668
669 /* Unfetch a byte from TOK, using the string buffer. */
670
671 static void
buf_ungetc(int c,struct tok_state * tok)672 buf_ungetc(int c, struct tok_state *tok) {
673 tok->str--;
674 assert(Py_CHARMASK(*tok->str) == c); /* tok->cur may point to read-only segment */
675 }
676
677 /* Set the readline function for TOK to ENC. For the string-based
678 tokenizer, this means to just record the encoding. */
679
680 static int
buf_setreadl(struct tok_state * tok,const char * enc)681 buf_setreadl(struct tok_state *tok, const char* enc) {
682 tok->enc = enc;
683 return 1;
684 }
685
686 /* Return a UTF-8 encoding Python string object from the
687 C byte string STR, which is encoded with ENC. */
688
689 static PyObject *
translate_into_utf8(const char * str,const char * enc)690 translate_into_utf8(const char* str, const char* enc) {
691 PyObject *utf8;
692 PyObject* buf = PyUnicode_Decode(str, strlen(str), enc, NULL);
693 if (buf == NULL)
694 return NULL;
695 utf8 = PyUnicode_AsUTF8String(buf);
696 Py_DECREF(buf);
697 return utf8;
698 }
699
700
701 static char *
translate_newlines(const char * s,int exec_input,struct tok_state * tok)702 translate_newlines(const char *s, int exec_input, struct tok_state *tok) {
703 int skip_next_lf = 0;
704 size_t needed_length = strlen(s) + 2, final_length;
705 char *buf, *current;
706 char c = '\0';
707 buf = PyMem_MALLOC(needed_length);
708 if (buf == NULL) {
709 tok->done = E_NOMEM;
710 return NULL;
711 }
712 for (current = buf; *s; s++, current++) {
713 c = *s;
714 if (skip_next_lf) {
715 skip_next_lf = 0;
716 if (c == '\n') {
717 c = *++s;
718 if (!c)
719 break;
720 }
721 }
722 if (c == '\r') {
723 skip_next_lf = 1;
724 c = '\n';
725 }
726 *current = c;
727 }
728 /* If this is exec input, add a newline to the end of the string if
729 there isn't one already. */
730 if (exec_input && c != '\n') {
731 *current = '\n';
732 current++;
733 }
734 *current = '\0';
735 final_length = current - buf + 1;
736 if (final_length < needed_length && final_length)
737 /* should never fail */
738 buf = PyMem_REALLOC(buf, final_length);
739 return buf;
740 }
741
742 /* Decode a byte string STR for use as the buffer of TOK.
743 Look for encoding declarations inside STR, and record them
744 inside TOK. */
745
746 static const char *
decode_str(const char * input,int single,struct tok_state * tok)747 decode_str(const char *input, int single, struct tok_state *tok)
748 {
749 PyObject* utf8 = NULL;
750 const char *str;
751 const char *s;
752 const char *newl[2] = {NULL, NULL};
753 int lineno = 0;
754 tok->input = str = translate_newlines(input, single, tok);
755 if (str == NULL)
756 return NULL;
757 tok->enc = NULL;
758 tok->str = str;
759 if (!check_bom(buf_getc, buf_ungetc, buf_setreadl, tok))
760 return error_ret(tok);
761 str = tok->str; /* string after BOM if any */
762 assert(str);
763 if (tok->enc != NULL) {
764 utf8 = translate_into_utf8(str, tok->enc);
765 if (utf8 == NULL)
766 return error_ret(tok);
767 str = PyBytes_AsString(utf8);
768 }
769 for (s = str;; s++) {
770 if (*s == '\0') break;
771 else if (*s == '\n') {
772 assert(lineno < 2);
773 newl[lineno] = s;
774 lineno++;
775 if (lineno == 2) break;
776 }
777 }
778 tok->enc = NULL;
779 /* need to check line 1 and 2 separately since check_coding_spec
780 assumes a single line as input */
781 if (newl[0]) {
782 if (!check_coding_spec(str, newl[0] - str, tok, buf_setreadl))
783 return error_ret(tok);
784 if (tok->enc == NULL && !tok->read_coding_spec && newl[1]) {
785 if (!check_coding_spec(newl[0]+1, newl[1] - newl[0],
786 tok, buf_setreadl))
787 return error_ret(tok);
788 }
789 }
790 if (tok->enc != NULL) {
791 assert(utf8 == NULL);
792 utf8 = translate_into_utf8(str, tok->enc);
793 if (utf8 == NULL)
794 return error_ret(tok);
795 str = PyBytes_AS_STRING(utf8);
796 }
797 assert(tok->decoding_buffer == NULL);
798 tok->decoding_buffer = utf8; /* CAUTION */
799 return str;
800 }
801
802 #endif /* PGEN */
803
804 /* Set up tokenizer for string */
805
806 struct tok_state *
PyTokenizer_FromString(const char * str,int exec_input)807 PyTokenizer_FromString(const char *str, int exec_input)
808 {
809 struct tok_state *tok = tok_new();
810 if (tok == NULL)
811 return NULL;
812 str = decode_str(str, exec_input, tok);
813 if (str == NULL) {
814 PyTokenizer_Free(tok);
815 return NULL;
816 }
817
818 /* XXX: constify members. */
819 tok->buf = tok->cur = tok->end = tok->inp = (char*)str;
820 return tok;
821 }
822
823 struct tok_state *
PyTokenizer_FromUTF8(const char * str,int exec_input)824 PyTokenizer_FromUTF8(const char *str, int exec_input)
825 {
826 struct tok_state *tok = tok_new();
827 if (tok == NULL)
828 return NULL;
829 #ifndef PGEN
830 tok->input = str = translate_newlines(str, exec_input, tok);
831 #endif
832 if (str == NULL) {
833 PyTokenizer_Free(tok);
834 return NULL;
835 }
836 tok->decoding_state = STATE_RAW;
837 tok->read_coding_spec = 1;
838 tok->enc = NULL;
839 tok->str = str;
840 tok->encoding = (char *)PyMem_MALLOC(6);
841 if (!tok->encoding) {
842 PyTokenizer_Free(tok);
843 return NULL;
844 }
845 strcpy(tok->encoding, "utf-8");
846
847 /* XXX: constify members. */
848 tok->buf = tok->cur = tok->end = tok->inp = (char*)str;
849 return tok;
850 }
851
852 /* Set up tokenizer for file */
853
854 struct tok_state *
PyTokenizer_FromFile(FILE * fp,const char * enc,const char * ps1,const char * ps2)855 PyTokenizer_FromFile(FILE *fp, const char* enc,
856 const char *ps1, const char *ps2)
857 {
858 struct tok_state *tok = tok_new();
859 if (tok == NULL)
860 return NULL;
861 if ((tok->buf = (char *)PyMem_MALLOC(BUFSIZ)) == NULL) {
862 PyTokenizer_Free(tok);
863 return NULL;
864 }
865 tok->cur = tok->inp = tok->buf;
866 tok->end = tok->buf + BUFSIZ;
867 tok->fp = fp;
868 tok->prompt = ps1;
869 tok->nextprompt = ps2;
870 if (enc != NULL) {
871 /* Must copy encoding declaration since it
872 gets copied into the parse tree. */
873 tok->encoding = PyMem_MALLOC(strlen(enc)+1);
874 if (!tok->encoding) {
875 PyTokenizer_Free(tok);
876 return NULL;
877 }
878 strcpy(tok->encoding, enc);
879 tok->decoding_state = STATE_NORMAL;
880 }
881 return tok;
882 }
883
884
885 /* Free a tok_state structure */
886
887 void
PyTokenizer_Free(struct tok_state * tok)888 PyTokenizer_Free(struct tok_state *tok)
889 {
890 if (tok->encoding != NULL)
891 PyMem_FREE(tok->encoding);
892 #ifndef PGEN
893 Py_XDECREF(tok->decoding_readline);
894 Py_XDECREF(tok->decoding_buffer);
895 Py_XDECREF(tok->filename);
896 #endif
897 if (tok->fp != NULL && tok->buf != NULL)
898 PyMem_FREE(tok->buf);
899 if (tok->input)
900 PyMem_FREE((char *)tok->input);
901 PyMem_FREE(tok);
902 }
903
904 /* Get next char, updating state; error code goes into tok->done */
905
906 static int
tok_nextc(struct tok_state * tok)907 tok_nextc(struct tok_state *tok)
908 {
909 for (;;) {
910 if (tok->cur != tok->inp) {
911 return Py_CHARMASK(*tok->cur++); /* Fast path */
912 }
913 if (tok->done != E_OK)
914 return EOF;
915 if (tok->fp == NULL) {
916 char *end = strchr(tok->inp, '\n');
917 if (end != NULL)
918 end++;
919 else {
920 end = strchr(tok->inp, '\0');
921 if (end == tok->inp) {
922 tok->done = E_EOF;
923 return EOF;
924 }
925 }
926 if (tok->start == NULL)
927 tok->buf = tok->cur;
928 tok->line_start = tok->cur;
929 tok->lineno++;
930 tok->inp = end;
931 return Py_CHARMASK(*tok->cur++);
932 }
933 if (tok->prompt != NULL) {
934 char *newtok = PyOS_Readline(stdin, stdout, tok->prompt);
935 #ifndef PGEN
936 if (newtok != NULL) {
937 char *translated = translate_newlines(newtok, 0, tok);
938 PyMem_FREE(newtok);
939 if (translated == NULL)
940 return EOF;
941 newtok = translated;
942 }
943 if (tok->encoding && newtok && *newtok) {
944 /* Recode to UTF-8 */
945 Py_ssize_t buflen;
946 const char* buf;
947 PyObject *u = translate_into_utf8(newtok, tok->encoding);
948 PyMem_FREE(newtok);
949 if (!u) {
950 tok->done = E_DECODE;
951 return EOF;
952 }
953 buflen = PyBytes_GET_SIZE(u);
954 buf = PyBytes_AS_STRING(u);
955 newtok = PyMem_MALLOC(buflen+1);
956 if (newtok == NULL) {
957 Py_DECREF(u);
958 tok->done = E_NOMEM;
959 return EOF;
960 }
961 strcpy(newtok, buf);
962 Py_DECREF(u);
963 }
964 #endif
965 if (tok->nextprompt != NULL)
966 tok->prompt = tok->nextprompt;
967 if (newtok == NULL)
968 tok->done = E_INTR;
969 else if (*newtok == '\0') {
970 PyMem_FREE(newtok);
971 tok->done = E_EOF;
972 }
973 else if (tok->start != NULL) {
974 size_t start = tok->start - tok->buf;
975 size_t oldlen = tok->cur - tok->buf;
976 size_t newlen = oldlen + strlen(newtok);
977 char *buf = tok->buf;
978 buf = (char *)PyMem_REALLOC(buf, newlen+1);
979 tok->lineno++;
980 if (buf == NULL) {
981 PyMem_FREE(tok->buf);
982 tok->buf = NULL;
983 PyMem_FREE(newtok);
984 tok->done = E_NOMEM;
985 return EOF;
986 }
987 tok->buf = buf;
988 tok->cur = tok->buf + oldlen;
989 tok->line_start = tok->cur;
990 strcpy(tok->buf + oldlen, newtok);
991 PyMem_FREE(newtok);
992 tok->inp = tok->buf + newlen;
993 tok->end = tok->inp + 1;
994 tok->start = tok->buf + start;
995 }
996 else {
997 tok->lineno++;
998 if (tok->buf != NULL)
999 PyMem_FREE(tok->buf);
1000 tok->buf = newtok;
1001 tok->cur = tok->buf;
1002 tok->line_start = tok->buf;
1003 tok->inp = strchr(tok->buf, '\0');
1004 tok->end = tok->inp + 1;
1005 }
1006 }
1007 else {
1008 int done = 0;
1009 Py_ssize_t cur = 0;
1010 char *pt;
1011 if (tok->start == NULL) {
1012 if (tok->buf == NULL) {
1013 tok->buf = (char *)
1014 PyMem_MALLOC(BUFSIZ);
1015 if (tok->buf == NULL) {
1016 tok->done = E_NOMEM;
1017 return EOF;
1018 }
1019 tok->end = tok->buf + BUFSIZ;
1020 }
1021 if (decoding_fgets(tok->buf, (int)(tok->end - tok->buf),
1022 tok) == NULL) {
1023 if (!tok->decoding_erred)
1024 tok->done = E_EOF;
1025 done = 1;
1026 }
1027 else {
1028 tok->done = E_OK;
1029 tok->inp = strchr(tok->buf, '\0');
1030 done = tok->inp == tok->buf || tok->inp[-1] == '\n';
1031 }
1032 }
1033 else {
1034 cur = tok->cur - tok->buf;
1035 if (decoding_feof(tok)) {
1036 tok->done = E_EOF;
1037 done = 1;
1038 }
1039 else
1040 tok->done = E_OK;
1041 }
1042 tok->lineno++;
1043 /* Read until '\n' or EOF */
1044 while (!done) {
1045 Py_ssize_t curstart = tok->start == NULL ? -1 :
1046 tok->start - tok->buf;
1047 Py_ssize_t curvalid = tok->inp - tok->buf;
1048 Py_ssize_t newsize = curvalid + BUFSIZ;
1049 char *newbuf = tok->buf;
1050 newbuf = (char *)PyMem_REALLOC(newbuf,
1051 newsize);
1052 if (newbuf == NULL) {
1053 tok->done = E_NOMEM;
1054 tok->cur = tok->inp;
1055 return EOF;
1056 }
1057 tok->buf = newbuf;
1058 tok->cur = tok->buf + cur;
1059 tok->line_start = tok->cur;
1060 tok->inp = tok->buf + curvalid;
1061 tok->end = tok->buf + newsize;
1062 tok->start = curstart < 0 ? NULL :
1063 tok->buf + curstart;
1064 if (decoding_fgets(tok->inp,
1065 (int)(tok->end - tok->inp),
1066 tok) == NULL) {
1067 /* Break out early on decoding
1068 errors, as tok->buf will be NULL
1069 */
1070 if (tok->decoding_erred)
1071 return EOF;
1072 /* Last line does not end in \n,
1073 fake one */
1074 strcpy(tok->inp, "\n");
1075 }
1076 tok->inp = strchr(tok->inp, '\0');
1077 done = tok->inp[-1] == '\n';
1078 }
1079 if (tok->buf != NULL) {
1080 tok->cur = tok->buf + cur;
1081 tok->line_start = tok->cur;
1082 /* replace "\r\n" with "\n" */
1083 /* For Mac leave the \r, giving a syntax error */
1084 pt = tok->inp - 2;
1085 if (pt >= tok->buf && *pt == '\r') {
1086 *pt++ = '\n';
1087 *pt = '\0';
1088 tok->inp = pt;
1089 }
1090 }
1091 }
1092 if (tok->done != E_OK) {
1093 if (tok->prompt != NULL)
1094 PySys_WriteStderr("\n");
1095 tok->cur = tok->inp;
1096 return EOF;
1097 }
1098 }
1099 /*NOTREACHED*/
1100 }
1101
1102
1103 /* Back-up one character */
1104
1105 static void
tok_backup(struct tok_state * tok,int c)1106 tok_backup(struct tok_state *tok, int c)
1107 {
1108 if (c != EOF) {
1109 if (--tok->cur < tok->buf)
1110 Py_FatalError("tok_backup: beginning of buffer");
1111 if (*tok->cur != c)
1112 *tok->cur = c;
1113 }
1114 }
1115
1116
1117 /* Return the token corresponding to a single character */
1118
1119 int
PyToken_OneChar(int c)1120 PyToken_OneChar(int c)
1121 {
1122 switch (c) {
1123 case '(': return LPAR;
1124 case ')': return RPAR;
1125 case '[': return LSQB;
1126 case ']': return RSQB;
1127 case ':': return COLON;
1128 case ',': return COMMA;
1129 case ';': return SEMI;
1130 case '+': return PLUS;
1131 case '-': return MINUS;
1132 case '*': return STAR;
1133 case '/': return SLASH;
1134 case '|': return VBAR;
1135 case '&': return AMPER;
1136 case '<': return LESS;
1137 case '>': return GREATER;
1138 case '=': return EQUAL;
1139 case '.': return DOT;
1140 case '%': return PERCENT;
1141 case '{': return LBRACE;
1142 case '}': return RBRACE;
1143 case '^': return CIRCUMFLEX;
1144 case '~': return TILDE;
1145 case '@': return AT;
1146 default: return OP;
1147 }
1148 }
1149
1150
1151 int
PyToken_TwoChars(int c1,int c2)1152 PyToken_TwoChars(int c1, int c2)
1153 {
1154 switch (c1) {
1155 case '=':
1156 switch (c2) {
1157 case '=': return EQEQUAL;
1158 }
1159 break;
1160 case '!':
1161 switch (c2) {
1162 case '=': return NOTEQUAL;
1163 }
1164 break;
1165 case '<':
1166 switch (c2) {
1167 case '>': return NOTEQUAL;
1168 case '=': return LESSEQUAL;
1169 case '<': return LEFTSHIFT;
1170 }
1171 break;
1172 case '>':
1173 switch (c2) {
1174 case '=': return GREATEREQUAL;
1175 case '>': return RIGHTSHIFT;
1176 }
1177 break;
1178 case '+':
1179 switch (c2) {
1180 case '=': return PLUSEQUAL;
1181 }
1182 break;
1183 case '-':
1184 switch (c2) {
1185 case '=': return MINEQUAL;
1186 case '>': return RARROW;
1187 }
1188 break;
1189 case '*':
1190 switch (c2) {
1191 case '*': return DOUBLESTAR;
1192 case '=': return STAREQUAL;
1193 }
1194 break;
1195 case '/':
1196 switch (c2) {
1197 case '/': return DOUBLESLASH;
1198 case '=': return SLASHEQUAL;
1199 }
1200 break;
1201 case '|':
1202 switch (c2) {
1203 case '=': return VBAREQUAL;
1204 }
1205 break;
1206 case '%':
1207 switch (c2) {
1208 case '=': return PERCENTEQUAL;
1209 }
1210 break;
1211 case '&':
1212 switch (c2) {
1213 case '=': return AMPEREQUAL;
1214 }
1215 break;
1216 case '^':
1217 switch (c2) {
1218 case '=': return CIRCUMFLEXEQUAL;
1219 }
1220 break;
1221 case '@':
1222 switch (c2) {
1223 case '=': return ATEQUAL;
1224 }
1225 break;
1226 }
1227 return OP;
1228 }
1229
1230 int
PyToken_ThreeChars(int c1,int c2,int c3)1231 PyToken_ThreeChars(int c1, int c2, int c3)
1232 {
1233 switch (c1) {
1234 case '<':
1235 switch (c2) {
1236 case '<':
1237 switch (c3) {
1238 case '=':
1239 return LEFTSHIFTEQUAL;
1240 }
1241 break;
1242 }
1243 break;
1244 case '>':
1245 switch (c2) {
1246 case '>':
1247 switch (c3) {
1248 case '=':
1249 return RIGHTSHIFTEQUAL;
1250 }
1251 break;
1252 }
1253 break;
1254 case '*':
1255 switch (c2) {
1256 case '*':
1257 switch (c3) {
1258 case '=':
1259 return DOUBLESTAREQUAL;
1260 }
1261 break;
1262 }
1263 break;
1264 case '/':
1265 switch (c2) {
1266 case '/':
1267 switch (c3) {
1268 case '=':
1269 return DOUBLESLASHEQUAL;
1270 }
1271 break;
1272 }
1273 break;
1274 case '.':
1275 switch (c2) {
1276 case '.':
1277 switch (c3) {
1278 case '.':
1279 return ELLIPSIS;
1280 }
1281 break;
1282 }
1283 break;
1284 }
1285 return OP;
1286 }
1287
1288 static int
indenterror(struct tok_state * tok)1289 indenterror(struct tok_state *tok)
1290 {
1291 tok->done = E_TABSPACE;
1292 tok->cur = tok->inp;
1293 return ERRORTOKEN;
1294 }
1295
1296 #ifdef PGEN
1297 #define verify_identifier(tok) 1
1298 #else
1299 /* Verify that the identifier follows PEP 3131.
1300 All identifier strings are guaranteed to be "ready" unicode objects.
1301 */
1302 static int
verify_identifier(struct tok_state * tok)1303 verify_identifier(struct tok_state *tok)
1304 {
1305 PyObject *s;
1306 int result;
1307 if (tok->decoding_erred)
1308 return 0;
1309 s = PyUnicode_DecodeUTF8(tok->start, tok->cur - tok->start, NULL);
1310 if (s == NULL || PyUnicode_READY(s) == -1) {
1311 if (PyErr_ExceptionMatches(PyExc_UnicodeDecodeError)) {
1312 PyErr_Clear();
1313 tok->done = E_IDENTIFIER;
1314 } else {
1315 tok->done = E_ERROR;
1316 }
1317 return 0;
1318 }
1319 result = PyUnicode_IsIdentifier(s);
1320 Py_DECREF(s);
1321 if (result == 0)
1322 tok->done = E_IDENTIFIER;
1323 return result;
1324 }
1325 #endif
1326
1327 static int
tok_decimal_tail(struct tok_state * tok)1328 tok_decimal_tail(struct tok_state *tok)
1329 {
1330 int c;
1331
1332 while (1) {
1333 do {
1334 c = tok_nextc(tok);
1335 } while (isdigit(c));
1336 if (c != '_') {
1337 break;
1338 }
1339 c = tok_nextc(tok);
1340 if (!isdigit(c)) {
1341 tok->done = E_TOKEN;
1342 tok_backup(tok, c);
1343 return 0;
1344 }
1345 }
1346 return c;
1347 }
1348
1349 /* Get next token, after space stripping etc. */
1350
1351 static int
tok_get(struct tok_state * tok,char ** p_start,char ** p_end)1352 tok_get(struct tok_state *tok, char **p_start, char **p_end)
1353 {
1354 int c;
1355 int blankline, nonascii;
1356
1357 *p_start = *p_end = NULL;
1358 nextline:
1359 tok->start = NULL;
1360 blankline = 0;
1361
1362 /* Get indentation level */
1363 if (tok->atbol) {
1364 int col = 0;
1365 int altcol = 0;
1366 tok->atbol = 0;
1367 for (;;) {
1368 c = tok_nextc(tok);
1369 if (c == ' ') {
1370 col++, altcol++;
1371 }
1372 else if (c == '\t') {
1373 col = (col / tok->tabsize + 1) * tok->tabsize;
1374 altcol = (altcol / ALTTABSIZE + 1) * ALTTABSIZE;
1375 }
1376 else if (c == '\014') {/* Control-L (formfeed) */
1377 col = altcol = 0; /* For Emacs users */
1378 }
1379 else {
1380 break;
1381 }
1382 }
1383 tok_backup(tok, c);
1384 if (c == '#' || c == '\n') {
1385 /* Lines with only whitespace and/or comments
1386 shouldn't affect the indentation and are
1387 not passed to the parser as NEWLINE tokens,
1388 except *totally* empty lines in interactive
1389 mode, which signal the end of a command group. */
1390 if (col == 0 && c == '\n' && tok->prompt != NULL) {
1391 blankline = 0; /* Let it through */
1392 }
1393 else {
1394 blankline = 1; /* Ignore completely */
1395 }
1396 /* We can't jump back right here since we still
1397 may need to skip to the end of a comment */
1398 }
1399 if (!blankline && tok->level == 0) {
1400 if (col == tok->indstack[tok->indent]) {
1401 /* No change */
1402 if (altcol != tok->altindstack[tok->indent]) {
1403 return indenterror(tok);
1404 }
1405 }
1406 else if (col > tok->indstack[tok->indent]) {
1407 /* Indent -- always one */
1408 if (tok->indent+1 >= MAXINDENT) {
1409 tok->done = E_TOODEEP;
1410 tok->cur = tok->inp;
1411 return ERRORTOKEN;
1412 }
1413 if (altcol <= tok->altindstack[tok->indent]) {
1414 return indenterror(tok);
1415 }
1416 tok->pendin++;
1417 tok->indstack[++tok->indent] = col;
1418 tok->altindstack[tok->indent] = altcol;
1419 }
1420 else /* col < tok->indstack[tok->indent] */ {
1421 /* Dedent -- any number, must be consistent */
1422 while (tok->indent > 0 &&
1423 col < tok->indstack[tok->indent]) {
1424 tok->pendin--;
1425 tok->indent--;
1426 }
1427 if (col != tok->indstack[tok->indent]) {
1428 tok->done = E_DEDENT;
1429 tok->cur = tok->inp;
1430 return ERRORTOKEN;
1431 }
1432 if (altcol != tok->altindstack[tok->indent]) {
1433 return indenterror(tok);
1434 }
1435 }
1436 }
1437 }
1438
1439 tok->start = tok->cur;
1440
1441 /* Return pending indents/dedents */
1442 if (tok->pendin != 0) {
1443 if (tok->pendin < 0) {
1444 tok->pendin++;
1445 return DEDENT;
1446 }
1447 else {
1448 tok->pendin--;
1449 return INDENT;
1450 }
1451 }
1452
1453 again:
1454 tok->start = NULL;
1455 /* Skip spaces */
1456 do {
1457 c = tok_nextc(tok);
1458 } while (c == ' ' || c == '\t' || c == '\014');
1459
1460 /* Set start of current token */
1461 tok->start = tok->cur - 1;
1462
1463 /* Skip comment */
1464 if (c == '#') {
1465 while (c != EOF && c != '\n') {
1466 c = tok_nextc(tok);
1467 }
1468 }
1469
1470 /* Check for EOF and errors now */
1471 if (c == EOF) {
1472 return tok->done == E_EOF ? ENDMARKER : ERRORTOKEN;
1473 }
1474
1475 /* Identifier (most frequent token!) */
1476 nonascii = 0;
1477 if (is_potential_identifier_start(c)) {
1478 /* Process the various legal combinations of b"", r"", u"", and f"". */
1479 int saw_b = 0, saw_r = 0, saw_u = 0, saw_f = 0;
1480 while (1) {
1481 if (!(saw_b || saw_u || saw_f) && (c == 'b' || c == 'B'))
1482 saw_b = 1;
1483 /* Since this is a backwards compatibility support literal we don't
1484 want to support it in arbitrary order like byte literals. */
1485 else if (!(saw_b || saw_u || saw_r || saw_f)
1486 && (c == 'u'|| c == 'U')) {
1487 saw_u = 1;
1488 }
1489 /* ur"" and ru"" are not supported */
1490 else if (!(saw_r || saw_u) && (c == 'r' || c == 'R')) {
1491 saw_r = 1;
1492 }
1493 else if (!(saw_f || saw_b || saw_u) && (c == 'f' || c == 'F')) {
1494 saw_f = 1;
1495 }
1496 else {
1497 break;
1498 }
1499 c = tok_nextc(tok);
1500 if (c == '"' || c == '\'') {
1501 goto letter_quote;
1502 }
1503 }
1504 while (is_potential_identifier_char(c)) {
1505 if (c >= 128) {
1506 nonascii = 1;
1507 }
1508 c = tok_nextc(tok);
1509 }
1510 tok_backup(tok, c);
1511 if (nonascii && !verify_identifier(tok)) {
1512 return ERRORTOKEN;
1513 }
1514 *p_start = tok->start;
1515 *p_end = tok->cur;
1516
1517 return NAME;
1518 }
1519
1520 /* Newline */
1521 if (c == '\n') {
1522 tok->atbol = 1;
1523 if (blankline || tok->level > 0) {
1524 goto nextline;
1525 }
1526 *p_start = tok->start;
1527 *p_end = tok->cur - 1; /* Leave '\n' out of the string */
1528 tok->cont_line = 0;
1529 return NEWLINE;
1530 }
1531
1532 /* Period or number starting with period? */
1533 if (c == '.') {
1534 c = tok_nextc(tok);
1535 if (isdigit(c)) {
1536 goto fraction;
1537 } else if (c == '.') {
1538 c = tok_nextc(tok);
1539 if (c == '.') {
1540 *p_start = tok->start;
1541 *p_end = tok->cur;
1542 return ELLIPSIS;
1543 }
1544 else {
1545 tok_backup(tok, c);
1546 }
1547 tok_backup(tok, '.');
1548 }
1549 else {
1550 tok_backup(tok, c);
1551 }
1552 *p_start = tok->start;
1553 *p_end = tok->cur;
1554 return DOT;
1555 }
1556
1557 /* Number */
1558 if (isdigit(c)) {
1559 if (c == '0') {
1560 /* Hex, octal or binary -- maybe. */
1561 c = tok_nextc(tok);
1562 if (c == 'x' || c == 'X') {
1563 /* Hex */
1564 c = tok_nextc(tok);
1565 do {
1566 if (c == '_') {
1567 c = tok_nextc(tok);
1568 }
1569 if (!isxdigit(c)) {
1570 tok->done = E_TOKEN;
1571 tok_backup(tok, c);
1572 return ERRORTOKEN;
1573 }
1574 do {
1575 c = tok_nextc(tok);
1576 } while (isxdigit(c));
1577 } while (c == '_');
1578 }
1579 else if (c == 'o' || c == 'O') {
1580 /* Octal */
1581 c = tok_nextc(tok);
1582 do {
1583 if (c == '_') {
1584 c = tok_nextc(tok);
1585 }
1586 if (c < '0' || c >= '8') {
1587 tok->done = E_TOKEN;
1588 tok_backup(tok, c);
1589 return ERRORTOKEN;
1590 }
1591 do {
1592 c = tok_nextc(tok);
1593 } while ('0' <= c && c < '8');
1594 } while (c == '_');
1595 }
1596 else if (c == 'b' || c == 'B') {
1597 /* Binary */
1598 c = tok_nextc(tok);
1599 do {
1600 if (c == '_') {
1601 c = tok_nextc(tok);
1602 }
1603 if (c != '0' && c != '1') {
1604 tok->done = E_TOKEN;
1605 tok_backup(tok, c);
1606 return ERRORTOKEN;
1607 }
1608 do {
1609 c = tok_nextc(tok);
1610 } while (c == '0' || c == '1');
1611 } while (c == '_');
1612 }
1613 else {
1614 int nonzero = 0;
1615 /* maybe old-style octal; c is first char of it */
1616 /* in any case, allow '0' as a literal */
1617 while (1) {
1618 if (c == '_') {
1619 c = tok_nextc(tok);
1620 if (!isdigit(c)) {
1621 tok->done = E_TOKEN;
1622 tok_backup(tok, c);
1623 return ERRORTOKEN;
1624 }
1625 }
1626 if (c != '0') {
1627 break;
1628 }
1629 c = tok_nextc(tok);
1630 }
1631 if (isdigit(c)) {
1632 nonzero = 1;
1633 c = tok_decimal_tail(tok);
1634 if (c == 0) {
1635 return ERRORTOKEN;
1636 }
1637 }
1638 if (c == '.') {
1639 c = tok_nextc(tok);
1640 goto fraction;
1641 }
1642 else if (c == 'e' || c == 'E') {
1643 goto exponent;
1644 }
1645 else if (c == 'j' || c == 'J') {
1646 goto imaginary;
1647 }
1648 else if (nonzero) {
1649 /* Old-style octal: now disallowed. */
1650 tok->done = E_TOKEN;
1651 tok_backup(tok, c);
1652 return ERRORTOKEN;
1653 }
1654 }
1655 }
1656 else {
1657 /* Decimal */
1658 c = tok_decimal_tail(tok);
1659 if (c == 0) {
1660 return ERRORTOKEN;
1661 }
1662 {
1663 /* Accept floating point numbers. */
1664 if (c == '.') {
1665 c = tok_nextc(tok);
1666 fraction:
1667 /* Fraction */
1668 if (isdigit(c)) {
1669 c = tok_decimal_tail(tok);
1670 if (c == 0) {
1671 return ERRORTOKEN;
1672 }
1673 }
1674 }
1675 if (c == 'e' || c == 'E') {
1676 int e;
1677 exponent:
1678 e = c;
1679 /* Exponent part */
1680 c = tok_nextc(tok);
1681 if (c == '+' || c == '-') {
1682 c = tok_nextc(tok);
1683 if (!isdigit(c)) {
1684 tok->done = E_TOKEN;
1685 tok_backup(tok, c);
1686 return ERRORTOKEN;
1687 }
1688 } else if (!isdigit(c)) {
1689 tok_backup(tok, c);
1690 tok_backup(tok, e);
1691 *p_start = tok->start;
1692 *p_end = tok->cur;
1693 return NUMBER;
1694 }
1695 c = tok_decimal_tail(tok);
1696 if (c == 0) {
1697 return ERRORTOKEN;
1698 }
1699 }
1700 if (c == 'j' || c == 'J') {
1701 /* Imaginary part */
1702 imaginary:
1703 c = tok_nextc(tok);
1704 }
1705 }
1706 }
1707 tok_backup(tok, c);
1708 *p_start = tok->start;
1709 *p_end = tok->cur;
1710 return NUMBER;
1711 }
1712
1713 letter_quote:
1714 /* String */
1715 if (c == '\'' || c == '"') {
1716 int quote = c;
1717 int quote_size = 1; /* 1 or 3 */
1718 int end_quote_size = 0;
1719
1720 /* Find the quote size and start of string */
1721 c = tok_nextc(tok);
1722 if (c == quote) {
1723 c = tok_nextc(tok);
1724 if (c == quote) {
1725 quote_size = 3;
1726 }
1727 else {
1728 end_quote_size = 1; /* empty string found */
1729 }
1730 }
1731 if (c != quote) {
1732 tok_backup(tok, c);
1733 }
1734
1735 /* Get rest of string */
1736 while (end_quote_size != quote_size) {
1737 c = tok_nextc(tok);
1738 if (c == EOF) {
1739 if (quote_size == 3) {
1740 tok->done = E_EOFS;
1741 }
1742 else {
1743 tok->done = E_EOLS;
1744 }
1745 tok->cur = tok->inp;
1746 return ERRORTOKEN;
1747 }
1748 if (quote_size == 1 && c == '\n') {
1749 tok->done = E_EOLS;
1750 tok->cur = tok->inp;
1751 return ERRORTOKEN;
1752 }
1753 if (c == quote) {
1754 end_quote_size += 1;
1755 }
1756 else {
1757 end_quote_size = 0;
1758 if (c == '\\') {
1759 tok_nextc(tok); /* skip escaped char */
1760 }
1761 }
1762 }
1763
1764 *p_start = tok->start;
1765 *p_end = tok->cur;
1766 return STRING;
1767 }
1768
1769 /* Line continuation */
1770 if (c == '\\') {
1771 c = tok_nextc(tok);
1772 if (c != '\n') {
1773 tok->done = E_LINECONT;
1774 tok->cur = tok->inp;
1775 return ERRORTOKEN;
1776 }
1777 tok->cont_line = 1;
1778 goto again; /* Read next line */
1779 }
1780
1781 /* Check for two-character token */
1782 {
1783 int c2 = tok_nextc(tok);
1784 int token = PyToken_TwoChars(c, c2);
1785 if (token != OP) {
1786 int c3 = tok_nextc(tok);
1787 int token3 = PyToken_ThreeChars(c, c2, c3);
1788 if (token3 != OP) {
1789 token = token3;
1790 }
1791 else {
1792 tok_backup(tok, c3);
1793 }
1794 *p_start = tok->start;
1795 *p_end = tok->cur;
1796 return token;
1797 }
1798 tok_backup(tok, c2);
1799 }
1800
1801 /* Keep track of parentheses nesting level */
1802 switch (c) {
1803 case '(':
1804 case '[':
1805 case '{':
1806 tok->level++;
1807 break;
1808 case ')':
1809 case ']':
1810 case '}':
1811 tok->level--;
1812 break;
1813 }
1814
1815 /* Punctuation character */
1816 *p_start = tok->start;
1817 *p_end = tok->cur;
1818 return PyToken_OneChar(c);
1819 }
1820
1821 int
PyTokenizer_Get(struct tok_state * tok,char ** p_start,char ** p_end)1822 PyTokenizer_Get(struct tok_state *tok, char **p_start, char **p_end)
1823 {
1824 int result = tok_get(tok, p_start, p_end);
1825 if (tok->decoding_erred) {
1826 result = ERRORTOKEN;
1827 tok->done = E_DECODE;
1828 }
1829 return result;
1830 }
1831
1832 /* Get the encoding of a Python file. Check for the coding cookie and check if
1833 the file starts with a BOM.
1834
1835 PyTokenizer_FindEncodingFilename() returns NULL when it can't find the
1836 encoding in the first or second line of the file (in which case the encoding
1837 should be assumed to be UTF-8).
1838
1839 The char* returned is malloc'ed via PyMem_MALLOC() and thus must be freed
1840 by the caller. */
1841
1842 char *
PyTokenizer_FindEncodingFilename(int fd,PyObject * filename)1843 PyTokenizer_FindEncodingFilename(int fd, PyObject *filename)
1844 {
1845 struct tok_state *tok;
1846 FILE *fp;
1847 char *p_start =NULL , *p_end =NULL , *encoding = NULL;
1848
1849 #ifndef PGEN
1850 fd = _Py_dup(fd);
1851 #else
1852 fd = dup(fd);
1853 #endif
1854 if (fd < 0) {
1855 return NULL;
1856 }
1857
1858 fp = fdopen(fd, "r");
1859 if (fp == NULL) {
1860 return NULL;
1861 }
1862 tok = PyTokenizer_FromFile(fp, NULL, NULL, NULL);
1863 if (tok == NULL) {
1864 fclose(fp);
1865 return NULL;
1866 }
1867 #ifndef PGEN
1868 if (filename != NULL) {
1869 Py_INCREF(filename);
1870 tok->filename = filename;
1871 }
1872 else {
1873 tok->filename = PyUnicode_FromString("<string>");
1874 if (tok->filename == NULL) {
1875 fclose(fp);
1876 PyTokenizer_Free(tok);
1877 return encoding;
1878 }
1879 }
1880 #endif
1881 while (tok->lineno < 2 && tok->done == E_OK) {
1882 PyTokenizer_Get(tok, &p_start, &p_end);
1883 }
1884 fclose(fp);
1885 if (tok->encoding) {
1886 encoding = (char *)PyMem_MALLOC(strlen(tok->encoding) + 1);
1887 if (encoding)
1888 strcpy(encoding, tok->encoding);
1889 }
1890 PyTokenizer_Free(tok);
1891 return encoding;
1892 }
1893
1894 char *
PyTokenizer_FindEncoding(int fd)1895 PyTokenizer_FindEncoding(int fd)
1896 {
1897 return PyTokenizer_FindEncodingFilename(fd, NULL);
1898 }
1899
1900 #ifdef Py_DEBUG
1901
1902 void
tok_dump(int type,char * start,char * end)1903 tok_dump(int type, char *start, char *end)
1904 {
1905 printf("%s", _PyParser_TokenNames[type]);
1906 if (type == NAME || type == NUMBER || type == STRING || type == OP)
1907 printf("(%.*s)", (int)(end - start), start);
1908 }
1909
1910 #endif
1911