forked from nothings/stb
-
Notifications
You must be signed in to change notification settings - Fork 0
/
stb_c_lexer.h
962 lines (867 loc) · 34.7 KB
/
stb_c_lexer.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
// stb_c_lexer.h - v0.09 - public domain Sean Barrett 2013
// lexer for making little C-like languages with recursive-descent parsers
//
// This file provides both the interface and the implementation.
// To instantiate the implementation,
// #define STB_C_LEXER_IMPLEMENTATION
// in *ONE* source file, before #including this file.
//
// The default configuration is fairly close to a C lexer, although
// suffixes on integer constants are not handled (you can override this).
//
// History:
// 0.09 hex floats, no-stdlib fixes
// 0.08 fix bad pointer comparison
// 0.07 fix mishandling of hexadecimal constants parsed by strtol
// 0.06 fix missing next character after ending quote mark (Andreas Fredriksson)
// 0.05 refixed get_location because github version had lost the fix
// 0.04 fix octal parsing bug
// 0.03 added STB_C_LEX_DISCARD_PREPROCESSOR option
// refactor API to simplify (only one struct instead of two)
// change literal enum names to have 'lit' at the end
// 0.02 first public release
//
// Status:
// - haven't tested compiling as C++
// - haven't tested the float parsing path
// - haven't tested the non-default-config paths (e.g. non-stdlib)
// - only tested default-config paths by eyeballing output of self-parse
//
// - haven't implemented multiline strings
// - haven't implemented octal/hex character constants
// - haven't implemented support for unicode CLEX_char
// - need to expand error reporting so you don't just get "CLEX_parse_error"
//
// Contributors:
// Arpad Goretity (bugfix)
// Alan Hickman (hex floats)
//
// LICENSE
//
// See end of file for license information.
#ifndef STB_C_LEXER_DEFINITIONS
// to change the default parsing rules, copy the following lines
// into your C/C++ file *before* including this, and then replace
// the Y's with N's for the ones you don't want.
// --BEGIN--
#define STB_C_LEX_C_DECIMAL_INTS Y // "0|[1-9][0-9]*" CLEX_intlit
#define STB_C_LEX_C_HEX_INTS Y // "0x[0-9a-fA-F]+" CLEX_intlit
#define STB_C_LEX_C_OCTAL_INTS Y // "[0-7]+" CLEX_intlit
#define STB_C_LEX_C_DECIMAL_FLOATS Y // "[0-9]*(.[0-9]*([eE][-+]?[0-9]+)?) CLEX_floatlit
#define STB_C_LEX_C99_HEX_FLOATS N // "0x{hex}+(.{hex}*)?[pP][-+]?{hex}+ CLEX_floatlit
#define STB_C_LEX_C_IDENTIFIERS Y // "[_a-zA-Z][_a-zA-Z0-9]*" CLEX_id
#define STB_C_LEX_C_DQ_STRINGS Y // double-quote-delimited strings with escapes CLEX_dqstring
#define STB_C_LEX_C_SQ_STRINGS N // single-quote-delimited strings with escapes CLEX_ssstring
#define STB_C_LEX_C_CHARS Y // single-quote-delimited character with escape CLEX_charlits
#define STB_C_LEX_C_COMMENTS Y // "/* comment */"
#define STB_C_LEX_CPP_COMMENTS Y // "// comment to end of line\n"
#define STB_C_LEX_C_COMPARISONS Y // "==" CLEX_eq "!=" CLEX_noteq "<=" CLEX_lesseq ">=" CLEX_greatereq
#define STB_C_LEX_C_LOGICAL Y // "&&" CLEX_andand "||" CLEX_oror
#define STB_C_LEX_C_SHIFTS Y // "<<" CLEX_shl ">>" CLEX_shr
#define STB_C_LEX_C_INCREMENTS Y // "++" CLEX_plusplus "--" CLEX_minusminus
#define STB_C_LEX_C_ARROW Y // "->" CLEX_arrow
#define STB_C_LEX_EQUAL_ARROW N // "=>" CLEX_eqarrow
#define STB_C_LEX_C_BITWISEEQ Y // "&=" CLEX_andeq "|=" CLEX_oreq "^=" CLEX_xoreq
#define STB_C_LEX_C_ARITHEQ Y // "+=" CLEX_pluseq "-=" CLEX_minuseq
// "*=" CLEX_muleq "/=" CLEX_diveq "%=" CLEX_modeq
// if both STB_C_LEX_SHIFTS & STB_C_LEX_ARITHEQ:
// "<<=" CLEX_shleq ">>=" CLEX_shreq
#define STB_C_LEX_PARSE_SUFFIXES N // letters after numbers are parsed as part of those numbers, and must be in suffix list below
#define STB_C_LEX_DECIMAL_SUFFIXES "" // decimal integer suffixes e.g. "uUlL" -- these are returned as-is in string storage
#define STB_C_LEX_HEX_SUFFIXES "" // e.g. "uUlL"
#define STB_C_LEX_OCTAL_SUFFIXES "" // e.g. "uUlL"
#define STB_C_LEX_FLOAT_SUFFIXES "" //
#define STB_C_LEX_0_IS_EOF N // if Y, ends parsing at '\0'; if N, returns '\0' as token
#define STB_C_LEX_INTEGERS_AS_DOUBLES N // parses integers as doubles so they can be larger than 'int', but only if STB_C_LEX_STDLIB==N
#define STB_C_LEX_MULTILINE_DSTRINGS N // allow newlines in double-quoted strings
#define STB_C_LEX_MULTILINE_SSTRINGS N // allow newlines in single-quoted strings
#define STB_C_LEX_USE_STDLIB Y // use strtod,strtol for parsing #s; otherwise inaccurate hack
#define STB_C_LEX_DOLLAR_IDENTIFIER Y // allow $ as an identifier character
#define STB_C_LEX_FLOAT_NO_DECIMAL Y // allow floats that have no decimal point if they have an exponent
#define STB_C_LEX_DEFINE_ALL_TOKEN_NAMES N // if Y, all CLEX_ token names are defined, even if never returned
// leaving it as N should help you catch config bugs
#define STB_C_LEX_DISCARD_PREPROCESSOR Y // discard C-preprocessor directives (e.g. after prepocess
// still have #line, #pragma, etc)
//#define STB_C_LEX_ISWHITE(str) ... // return length in bytes of whitespace characters if first char is whitespace
#define STB_C_LEXER_DEFINITIONS // This line prevents the header file from replacing your definitions
// --END--
#endif
#ifndef INCLUDE_STB_C_LEXER_H
#define INCLUDE_STB_C_LEXER_H
typedef struct
{
// lexer variables
char *input_stream;
char *eof;
char *parse_point;
char *string_storage;
int string_storage_len;
// lexer parse location for error messages
char *where_firstchar;
char *where_lastchar;
// lexer token variables
long token;
double real_number;
long int_number;
char *string;
int string_len;
} stb_lexer;
typedef struct
{
int line_number;
int line_offset;
} stb_lex_location;
#ifdef __cplusplus
extern "C" {
#endif
extern void stb_c_lexer_init(stb_lexer *lexer, const char *input_stream, const char *input_stream_end, char *string_store, int store_length);
// this function initialize the 'lexer' structure
// Input:
// - input_stream points to the file to parse, loaded into memory
// - input_stream_end points to the end of the file, or NULL if you use 0-for-EOF
// - string_store is storage the lexer can use for storing parsed strings and identifiers
// - store_length is the length of that storage
extern int stb_c_lexer_get_token(stb_lexer *lexer);
// this function returns non-zero if a token is parsed, or 0 if at EOF
// Output:
// - lexer->token is the token ID, which is unicode code point for a single-char token, < 0 for a multichar or eof or error
// - lexer->real_number is a double constant value for CLEX_floatlit, or CLEX_intlit if STB_C_LEX_INTEGERS_AS_DOUBLES
// - lexer->int_number is an integer constant for CLEX_intlit if !STB_C_LEX_INTEGERS_AS_DOUBLES, or character for CLEX_charlit
// - lexer->string is a 0-terminated string for CLEX_dqstring or CLEX_sqstring or CLEX_identifier
// - lexer->string_len is the byte length of lexer->string
extern void stb_c_lexer_get_location(const stb_lexer *lexer, const char *where, stb_lex_location *loc);
// this inefficient function returns the line number and character offset of a
// given location in the file as returned by stb_lex_token. Because it's inefficient,
// you should only call it for errors, not for every token.
// For error messages of invalid tokens, you typically want the location of the start
// of the token (which caused the token to be invalid). For bugs involving legit
// tokens, you can report the first or the range.
// Output:
// - loc->line_number is the line number in the file, counting from 1, of the location
// - loc->line_offset is the char-offset in the line, counting from 0, of the location
#ifdef __cplusplus
}
#endif
#endif // INCLUDE_STB_C_LEXER_H
#ifdef STB_C_LEXER_IMPLEMENTATION
#if defined(Y) || defined(N)
#error "Can only use stb_c_lexer in contexts where the preprocessor symbols 'Y' and 'N' are not defined"
#endif
// Hacky definitions so we can easily #if on them
#define Y(x) 1
#define N(x) 0
#if STB_C_LEX_INTEGERS_AS_DOUBLES(x)
typedef double stb__clex_int;
#define intfield real_number
#define STB__clex_int_as_double
#else
typedef long stb__clex_int;
#define intfield int_number
#endif
// Convert these config options to simple conditional #defines so we can more
// easily test them once we've change the meaning of Y/N
#if STB_C_LEX_PARSE_SUFFIXES(x)
#define STB__clex_parse_suffixes
#endif
#if STB_C_LEX_C_DECIMAL_INTS(x) || STB_C_LEX_C_HEX_INTS(x) || STB_C_LEX_DEFINE_ALL_TOKEN_NAMES(x)
#define STB__clex_define_int
#endif
#if (STB_C_LEX_C_ARITHEQ(x) && STB_C_LEX_C_SHIFTS(x)) || STB_C_LEX_DEFINE_ALL_TOKEN_NAMES(x)
#define STB__clex_define_shifts
#endif
#if STB_C_LEX_C99_HEX_FLOATS(x)
#define STB__clex_hex_floats
#endif
#if STB_C_LEX_C_HEX_INTS(x)
#define STB__clex_hex_ints
#endif
#if STB_C_LEX_C_DECIMAL_INTS(x)
#define STB__clex_decimal_ints
#endif
#if STB_C_LEX_C_OCTAL_INTS(x)
#define STB__clex_octal_ints
#endif
#if STB_C_LEX_C_DECIMAL_FLOATS(x)
#define STB__clex_decimal_floats
#endif
#if STB_C_LEX_DISCARD_PREPROCESSOR(x)
#define STB__clex_discard_preprocessor
#endif
#if STB_C_LEX_USE_STDLIB(x) && (!defined(STB__clex_hex_floats) || __STDC_VERSION__ >= 199901L)
#define STB__CLEX_use_stdlib
#include <stdlib.h>
#endif
// Now pick a definition of Y/N that's conducive to
// defining the enum of token names.
#if STB_C_LEX_DEFINE_ALL_TOKEN_NAMES(x) || defined(STB_C_LEXER_SELF_TEST)
#undef N
#define N(a) Y(a)
#else
#undef N
#define N(a)
#endif
#undef Y
#define Y(a) a,
enum
{
CLEX_eof = 256,
CLEX_parse_error,
#ifdef STB__clex_define_int
CLEX_intlit,
#endif
STB_C_LEX_C_DECIMAL_FLOATS( CLEX_floatlit )
STB_C_LEX_C_IDENTIFIERS( CLEX_id )
STB_C_LEX_C_DQ_STRINGS( CLEX_dqstring )
STB_C_LEX_C_SQ_STRINGS( CLEX_sqstring )
STB_C_LEX_C_CHARS( CLEX_charlit )
STB_C_LEX_C_COMPARISONS( CLEX_eq )
STB_C_LEX_C_COMPARISONS( CLEX_noteq )
STB_C_LEX_C_COMPARISONS( CLEX_lesseq )
STB_C_LEX_C_COMPARISONS( CLEX_greatereq )
STB_C_LEX_C_LOGICAL( CLEX_andand )
STB_C_LEX_C_LOGICAL( CLEX_oror )
STB_C_LEX_C_SHIFTS( CLEX_shl )
STB_C_LEX_C_SHIFTS( CLEX_shr )
STB_C_LEX_C_INCREMENTS( CLEX_plusplus )
STB_C_LEX_C_INCREMENTS( CLEX_minusminus )
STB_C_LEX_C_ARITHEQ( CLEX_pluseq )
STB_C_LEX_C_ARITHEQ( CLEX_minuseq )
STB_C_LEX_C_ARITHEQ( CLEX_muleq )
STB_C_LEX_C_ARITHEQ( CLEX_diveq )
STB_C_LEX_C_ARITHEQ( CLEX_modeq )
STB_C_LEX_C_BITWISEEQ( CLEX_andeq )
STB_C_LEX_C_BITWISEEQ( CLEX_oreq )
STB_C_LEX_C_BITWISEEQ( CLEX_xoreq )
STB_C_LEX_C_ARROW( CLEX_arrow )
STB_C_LEX_EQUAL_ARROW( CLEX_eqarrow )
#ifdef STB__clex_define_shifts
CLEX_shleq, CLEX_shreq,
#endif
CLEX_first_unused_token
#undef Y
#define Y(a) a
};
// Now for the rest of the file we'll use the basic definition where
// where Y expands to its contents and N expands to nothing
#undef N
#define N(a)
// API function
void stb_c_lexer_init(stb_lexer *lexer, const char *input_stream, const char *input_stream_end, char *string_store, int store_length)
{
lexer->input_stream = (char *) input_stream;
lexer->eof = (char *) input_stream_end;
lexer->parse_point = (char *) input_stream;
lexer->string_storage = string_store;
lexer->string_storage_len = store_length;
}
// API function
void stb_c_lexer_get_location(const stb_lexer *lexer, const char *where, stb_lex_location *loc)
{
char *p = lexer->input_stream;
int line_number = 1;
int char_offset = 0;
while (*p && p < where) {
if (*p == '\n' || *p == '\r') {
p += (p[0]+p[1] == '\r'+'\n' ? 2 : 1); // skip newline
line_number += 1;
char_offset = 0;
} else {
++p;
++char_offset;
}
}
loc->line_number = line_number;
loc->line_offset = char_offset;
}
// main helper function for returning a parsed token
static int stb__clex_token(stb_lexer *lexer, int token, char *start, char *end)
{
lexer->token = token;
lexer->where_firstchar = start;
lexer->where_lastchar = end;
lexer->parse_point = end+1;
return 1;
}
// helper function for returning eof
static int stb__clex_eof(stb_lexer *lexer)
{
lexer->token = CLEX_eof;
return 0;
}
static int stb__clex_iswhite(int x)
{
return x == ' ' || x == '\t' || x == '\r' || x == '\n' || x == '\f';
}
static const char *stb__strchr(const char *str, int ch)
{
for (; *str; ++str)
if (*str == ch)
return str;
return 0;
}
// parse suffixes at the end of a number
static int stb__clex_parse_suffixes(stb_lexer *lexer, long tokenid, char *start, char *cur, const char *suffixes)
{
#ifdef STB__clex_parse_suffixes
lexer->string = lexer->string_storage;
lexer->string_len = 0;
while ((*cur >= 'a' && *cur <= 'z') || (*cur >= 'A' && *cur <= 'Z')) {
if (stb__strchr(suffixes, *cur) == 0)
return stb__clex_token(lexer, CLEX_parse_error, start, cur);
if (lexer->string_len+1 >= lexer->string_storage_len)
return stb__clex_token(lexer, CLEX_parse_error, start, cur);
lexer->string[lexer->string_len++] = *cur++;
}
#else
suffixes = suffixes; // attempt to suppress warnings
#endif
return stb__clex_token(lexer, tokenid, start, cur-1);
}
#ifndef STB__CLEX_use_stdlib
static double stb__clex_pow(double base, unsigned int exponent)
{
double value=1;
for ( ; exponent; exponent >>= 1) {
if (exponent & 1)
value *= base;
base *= base;
}
return value;
}
static double stb__clex_parse_float(char *p, char **q)
{
char *s = p;
double value=0;
int base=10;
int exponent=0;
#ifdef STB__clex_hex_floats
if (*p == '0') {
if (p[1] == 'x' || p[1] == 'X') {
base=16;
p += 2;
}
}
#endif
for (;;) {
if (*p >= '0' && *p <= '9')
value = value*base + (*p++ - '0');
#ifdef STB__clex_hex_floats
else if (base == 16 && *p >= 'a' && *p <= 'f')
value = value*base + 10 + (*p++ - 'a');
else if (base == 16 && *p >= 'A' && *p <= 'F')
value = value*base + 10 + (*p++ - 'A');
#endif
else
break;
}
if (*p == '.') {
double pow, addend = 0;
++p;
for (pow=1; ; pow*=base) {
if (*p >= '0' && *p <= '9')
addend = addend*base + (*p++ - '0');
#ifdef STB__clex_hex_floats
else if (base == 16 && *p >= 'a' && *p <= 'f')
addend = addend*base + 10 + (*p++ - 'a');
else if (base == 16 && *p >= 'A' && *p <= 'F')
addend = addend*base + 10 + (*p++ - 'A');
#endif
else
break;
}
value += addend / pow;
}
#ifdef STB__clex_hex_floats
if (base == 16) {
// exponent required for hex float literal
if (*p != 'p' && *p != 'P') {
*q = s;
return 0;
}
exponent = 1;
} else
#endif
exponent = (*p == 'e' || *p == 'E');
if (exponent) {
int sign = p[1] == '-';
unsigned int exponent=0;
double power=1;
++p;
if (*p == '-' || *p == '+')
++p;
while (*p >= '0' && *p <= '9')
exponent = exponent*10 + (*p++ - '0');
#ifdef STB__clex_hex_floats
if (base == 16)
power = stb__clex_pow(2, exponent);
else
#endif
power = stb__clex_pow(10, exponent);
if (sign)
value /= power;
else
value *= power;
}
*q = p;
return value;
}
#endif
static int stb__clex_parse_char(char *p, char **q)
{
if (*p == '\\') {
*q = p+2; // tentatively guess we'll parse two characters
switch(p[1]) {
case '\\': return '\\';
case '\'': return '\'';
case '"': return '"';
case 't': return '\t';
case 'f': return '\f';
case 'n': return '\n';
case 'r': return '\r';
case '0': return '\0'; // @TODO ocatal constants
case 'x': case 'X': return -1; // @TODO hex constants
case 'u': return -1; // @TODO unicode constants
}
}
*q = p+1;
return (unsigned char) *p;
}
static int stb__clex_parse_string(stb_lexer *lexer, char *p, int type)
{
char *start = p;
char delim = *p++; // grab the " or ' for later matching
char *out = lexer->string_storage;
char *outend = lexer->string_storage + lexer->string_storage_len;
while (*p != delim) {
int n;
if (*p == '\\') {
char *q;
n = stb__clex_parse_char(p, &q);
if (n < 0)
return stb__clex_token(lexer, CLEX_parse_error, start, q);
p = q;
} else {
// @OPTIMIZE: could speed this up by looping-while-not-backslash
n = (unsigned char) *p++;
}
if (out+1 > outend)
return stb__clex_token(lexer, CLEX_parse_error, start, p);
// @TODO expand unicode escapes to UTF8
*out++ = (char) n;
}
*out = 0;
lexer->string = lexer->string_storage;
lexer->string_len = out - lexer->string_storage;
return stb__clex_token(lexer, type, start, p);
}
int stb_c_lexer_get_token(stb_lexer *lexer)
{
char *p = lexer->parse_point;
// skip whitespace and comments
for (;;) {
#ifdef STB_C_LEX_ISWHITE
while (p != lexer->stream_end) {
int n;
n = STB_C_LEX_ISWHITE(p);
if (n == 0) break;
if (lexer->eof && lexer->eof - lexer->parse_point < n)
return stb__clex_token(tok, CLEX_parse_error, p,lexer->eof-1);
p += n;
}
#else
while (p != lexer->eof && stb__clex_iswhite(*p))
++p;
#endif
STB_C_LEX_CPP_COMMENTS(
if (p != lexer->eof && p[0] == '/' && p[1] == '/') {
while (p != lexer->eof && *p != '\r' && *p != '\n')
++p;
continue;
}
)
STB_C_LEX_C_COMMENTS(
if (p != lexer->eof && p[0] == '/' && p[1] == '*') {
char *start = p;
p += 2;
while (p != lexer->eof && (p[0] != '*' || p[1] != '/'))
++p;
if (p == lexer->eof)
return stb__clex_token(lexer, CLEX_parse_error, start, p-1);
p += 2;
continue;
}
)
#ifdef STB__clex_discard_preprocessor
// @TODO this discards everything after a '#', regardless
// of where in the line the # is, rather than requiring it
// be at the start. (because this parser doesn't otherwise
// check for line breaks!)
if (p != lexer->eof && p[0] == '#') {
while (p != lexer->eof && *p != '\r' && *p != '\n')
++p;
continue;
}
#endif
break;
}
if (p == lexer->eof)
return stb__clex_eof(lexer);
switch (*p) {
default:
if ( (*p >= 'a' && *p <= 'z')
|| (*p >= 'A' && *p <= 'Z')
|| *p == '_' || (unsigned char) *p >= 128 // >= 128 is UTF8 char
STB_C_LEX_DOLLAR_IDENTIFIER( || *p == '$' ) )
{
int n = 0;
lexer->string = lexer->string_storage;
lexer->string_len = n;
do {
if (n+1 >= lexer->string_storage_len)
return stb__clex_token(lexer, CLEX_parse_error, p, p+n);
lexer->string[n] = p[n];
++n;
} while (
(p[n] >= 'a' && p[n] <= 'z')
|| (p[n] >= 'A' && p[n] <= 'Z')
|| (p[n] >= '0' && p[n] <= '9') // allow digits in middle of identifier
|| p[n] == '_' || (unsigned char) p[n] >= 128
STB_C_LEX_DOLLAR_IDENTIFIER( || p[n] == '$' )
);
lexer->string[n] = 0;
return stb__clex_token(lexer, CLEX_id, p, p+n-1);
}
// check for EOF
STB_C_LEX_0_IS_EOF(
if (*p == 0)
return stb__clex_eof(tok);
)
single_char:
// not an identifier, return the character as itself
return stb__clex_token(lexer, *p, p, p);
case '+':
if (p+1 != lexer->eof) {
STB_C_LEX_C_INCREMENTS(if (p[1] == '+') return stb__clex_token(lexer, CLEX_plusplus, p,p+1);)
STB_C_LEX_C_ARITHEQ( if (p[1] == '=') return stb__clex_token(lexer, CLEX_pluseq , p,p+1);)
}
goto single_char;
case '-':
if (p+1 != lexer->eof) {
STB_C_LEX_C_INCREMENTS(if (p[1] == '-') return stb__clex_token(lexer, CLEX_minusminus, p,p+1);)
STB_C_LEX_C_ARITHEQ( if (p[1] == '=') return stb__clex_token(lexer, CLEX_minuseq , p,p+1);)
STB_C_LEX_C_ARROW( if (p[1] == '>') return stb__clex_token(lexer, CLEX_arrow , p,p+1);)
}
goto single_char;
case '&':
if (p+1 != lexer->eof) {
STB_C_LEX_C_LOGICAL( if (p[1] == '&') return stb__clex_token(lexer, CLEX_andand, p,p+1);)
STB_C_LEX_C_BITWISEEQ(if (p[1] == '=') return stb__clex_token(lexer, CLEX_andeq , p,p+1);)
}
goto single_char;
case '|':
if (p+1 != lexer->eof) {
STB_C_LEX_C_LOGICAL( if (p[1] == '|') return stb__clex_token(lexer, CLEX_oror, p,p+1);)
STB_C_LEX_C_BITWISEEQ(if (p[1] == '=') return stb__clex_token(lexer, CLEX_oreq, p,p+1);)
}
goto single_char;
case '=':
if (p+1 != lexer->eof) {
STB_C_LEX_C_COMPARISONS(if (p[1] == '=') return stb__clex_token(lexer, CLEX_eq, p,p+1);)
STB_C_LEX_EQUAL_ARROW( if (p[1] == '>') return stb__clex_token(lexer, CLEX_eqarrow, p,p+1);)
}
goto single_char;
case '!':
STB_C_LEX_C_COMPARISONS(if (p+1 != lexer->eof && p[1] == '=') return stb__clex_token(lexer, CLEX_noteq, p,p+1);)
goto single_char;
case '^':
STB_C_LEX_C_BITWISEEQ(if (p+1 != lexer->eof && p[1] == '=') return stb__clex_token(lexer, CLEX_xoreq, p,p+1));
goto single_char;
case '%':
STB_C_LEX_C_ARITHEQ(if (p+1 != lexer->eof && p[1] == '=') return stb__clex_token(lexer, CLEX_modeq, p,p+1));
goto single_char;
case '*':
STB_C_LEX_C_ARITHEQ(if (p+1 != lexer->eof && p[1] == '=') return stb__clex_token(lexer, CLEX_muleq, p,p+1));
goto single_char;
case '/':
STB_C_LEX_C_ARITHEQ(if (p+1 != lexer->eof && p[1] == '=') return stb__clex_token(lexer, CLEX_diveq, p,p+1));
goto single_char;
case '<':
if (p+1 != lexer->eof) {
STB_C_LEX_C_COMPARISONS(if (p[1] == '=') return stb__clex_token(lexer, CLEX_lesseq, p,p+1);)
STB_C_LEX_C_SHIFTS( if (p[1] == '<') {
STB_C_LEX_C_ARITHEQ(if (p+2 != lexer->eof && p[2] == '=')
return stb__clex_token(lexer, CLEX_shleq, p,p+2);)
return stb__clex_token(lexer, CLEX_shl, p,p+1);
}
)
}
goto single_char;
case '>':
if (p+1 != lexer->eof) {
STB_C_LEX_C_COMPARISONS(if (p[1] == '=') return stb__clex_token(lexer, CLEX_greatereq, p,p+1);)
STB_C_LEX_C_SHIFTS( if (p[1] == '>') {
STB_C_LEX_C_ARITHEQ(if (p+2 != lexer->eof && p[2] == '=')
return stb__clex_token(lexer, CLEX_shreq, p,p+2);)
return stb__clex_token(lexer, CLEX_shr, p,p+1);
}
)
}
goto single_char;
case '"':
STB_C_LEX_C_DQ_STRINGS(return stb__clex_parse_string(lexer, p, CLEX_dqstring);)
goto single_char;
case '\'':
STB_C_LEX_C_SQ_STRINGS(return stb__clex_parse_string(lexer, p, CLEX_sqstring);)
STB_C_LEX_C_CHARS(
{
char *start = p;
lexer->int_number = stb__clex_parse_char(p+1, &p);
if (lexer->int_number < 0)
return stb__clex_token(lexer, CLEX_parse_error, start,start);
if (p == lexer->eof || *p != '\'')
return stb__clex_token(lexer, CLEX_parse_error, start,p);
return stb__clex_token(lexer, CLEX_charlit, start, p+1);
})
goto single_char;
case '0':
#if defined(STB__clex_hex_ints) || defined(STB__clex_hex_floats)
if (p+1 != lexer->eof) {
if (p[1] == 'x' || p[1] == 'X') {
char *q;
#ifdef STB__clex_hex_floats
for (q=p+2;
q != lexer->eof && ((*q >= '0' && *q <= '9') || (*q >= 'a' && *q <= 'f') || (*q >= 'A' && *q <= 'F'));
++q);
if (q != lexer->eof) {
if (*q == '.' STB_C_LEX_FLOAT_NO_DECIMAL(|| *q == 'p' || *q == 'P')) {
#ifdef STB__CLEX_use_stdlib
lexer->real_number = strtod((char *) p, (char**) &q);
#else
lexer->real_number = stb__clex_parse_float(p, &q);
#endif
if (p == q)
return stb__clex_token(lexer, CLEX_parse_error, p,q);
return stb__clex_parse_suffixes(lexer, CLEX_floatlit, p,q, STB_C_LEX_FLOAT_SUFFIXES);
}
}
#endif // STB__CLEX_hex_floats
#ifdef STB__clex_hex_ints
#ifdef STB__CLEX_use_stdlib
lexer->int_number = strtol((char *) p, (char **) &q, 16);
#else
{
stb__clex_int n=0;
for (q=p+2; q != lexer->eof; ++q) {
if (*q >= '0' && *q <= '9')
n = n*16 + (*q - '0');
else if (*q >= 'a' && *q <= 'f')
n = n*16 + (*q - 'a') + 10;
else if (*q >= 'A' && *q <= 'F')
n = n*16 + (*q - 'A') + 10;
else
break;
}
lexer->int_number = n;
}
#endif
if (q == p+2)
return stb__clex_token(lexer, CLEX_parse_error, p-2,p-1);
return stb__clex_parse_suffixes(lexer, CLEX_intlit, p,q, STB_C_LEX_HEX_SUFFIXES);
#endif
}
}
#endif // defined(STB__clex_hex_ints) || defined(STB__clex_hex_floats)
// can't test for octal because we might parse '0.0' as float or as '0' '.' '0',
// so have to do float first
/* FALL THROUGH */
case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9':
#ifdef STB__clex_decimal_floats
{
char *q = p;
while (q != lexer->eof && (*q >= '0' && *q <= '9'))
++q;
if (q != lexer->eof) {
if (*q == '.' STB_C_LEX_FLOAT_NO_DECIMAL(|| *q == 'e' || *q == 'E')) {
#ifdef STB__CLEX_use_stdlib
lexer->real_number = strtod((char *) p, (char**) &q);
#else
lexer->real_number = stb__clex_parse_float(p, &q);
#endif
return stb__clex_parse_suffixes(lexer, CLEX_floatlit, p,q, STB_C_LEX_FLOAT_SUFFIXES);
}
}
}
#endif // STB__clex_decimal_floats
#ifdef STB__clex_octal_ints
if (p[0] == '0') {
char *q = p;
#ifdef STB__CLEX_use_stdlib
lexer->int_number = strtol((char *) p, (char **) &q, 8);
#else
stb__clex_int n=0;
while (q != lexer->eof) {
if (*q >= '0' && *q <= '7')
n = n*8 + (*q - '0');
else
break;
++q;
}
if (q != lexer->eof && (*q == '8' || *q=='9'))
return stb__clex_token(lexer, CLEX_parse_error, p, q);
lexer->int_number = n;
#endif
return stb__clex_parse_suffixes(lexer, CLEX_intlit, p,q, STB_C_LEX_OCTAL_SUFFIXES);
}
#endif // STB__clex_octal_ints
#ifdef STB__clex_decimal_ints
{
char *q = p;
#ifdef STB__CLEX_use_stdlib
lexer->int_number = strtol((char *) p, (char **) &q, 10);
#else
stb__clex_int n=0;
while (q != lexer->eof) {
if (*q >= '0' && *q <= '9')
n = n*10 + (*q - '0');
else
break;
++q;
}
lexer->int_number = n;
#endif
return stb__clex_parse_suffixes(lexer, CLEX_intlit, p,q, STB_C_LEX_OCTAL_SUFFIXES);
}
#endif // STB__clex_decimal_ints
goto single_char;
}
}
#endif // STB_C_LEXER_IMPLEMENTATION
#ifdef STB_C_LEXER_SELF_TEST
#include <stdio.h>
#include <stdlib.h>
static void print_token(stb_lexer *lexer)
{
switch (lexer->token) {
case CLEX_id : printf("_%s", lexer->string); break;
case CLEX_eq : printf("=="); break;
case CLEX_noteq : printf("!="); break;
case CLEX_lesseq : printf("<="); break;
case CLEX_greatereq : printf(">="); break;
case CLEX_andand : printf("&&"); break;
case CLEX_oror : printf("||"); break;
case CLEX_shl : printf("<<"); break;
case CLEX_shr : printf(">>"); break;
case CLEX_plusplus : printf("++"); break;
case CLEX_minusminus: printf("--"); break;
case CLEX_arrow : printf("->"); break;
case CLEX_andeq : printf("&="); break;
case CLEX_oreq : printf("|="); break;
case CLEX_xoreq : printf("^="); break;
case CLEX_pluseq : printf("+="); break;
case CLEX_minuseq : printf("-="); break;
case CLEX_muleq : printf("*="); break;
case CLEX_diveq : printf("/="); break;
case CLEX_modeq : printf("%%="); break;
case CLEX_shleq : printf("<<="); break;
case CLEX_shreq : printf(">>="); break;
case CLEX_eqarrow : printf("=>"); break;
case CLEX_dqstring : printf("\"%s\"", lexer->string); break;
case CLEX_sqstring : printf("'\"%s\"'", lexer->string); break;
case CLEX_charlit : printf("'%s'", lexer->string); break;
#if defined(STB__clex_int_as_double) && !defined(STB__CLEX_use_stdlib)
case CLEX_intlit : printf("#%g", lexer->real_number); break;
#else
case CLEX_intlit : printf("#%ld", lexer->int_number); break;
#endif
case CLEX_floatlit : printf("%g", lexer->real_number); break;
default:
if (lexer->token >= 0 && lexer->token < 256)
printf("%c", (int) lexer->token);
else {
printf("<<<UNKNOWN TOKEN %ld >>>\n", lexer->token);
}
break;
}
}
/* Force a test
of parsing
multiline comments */
/*/ comment /*/
/**/ extern /**/
void dummy(void)
{
double some_floats[] = {
1.0501, -10.4e12, 5E+10,
#if 0 // not support in C++ or C-pre-99, so don't try to compile it
0x1.0p+24, 0xff.FP-8, 0x1p-23,
#endif
4.
};
printf("test %d",1); // https://github.com/nothings/stb/issues/13
}
int main(int argc, char **argv)
{
FILE *f = fopen("stb_c_lexer.h","rb");
char *text = (char *) malloc(1 << 20);
int len = f ? fread(text, 1, 1<<20, f) : -1;
stb_lexer lex;
if (len < 0) {
fprintf(stderr, "Error opening file\n");
free(text);
fclose(f);
return 1;
}
fclose(f);
stb_c_lexer_init(&lex, text, text+len, (char *) malloc(0x10000), 0x10000);
while (stb_c_lexer_get_token(&lex)) {
if (lex.token == CLEX_parse_error) {
printf("\n<<<PARSE ERROR>>>\n");
break;
}
print_token(&lex);
printf(" ");
}
return 0;
}
#endif
/*
------------------------------------------------------------------------------
This software is available under 2 licenses -- choose whichever you prefer.
------------------------------------------------------------------------------
ALTERNATIVE A - MIT License
Copyright (c) 2017 Sean Barrett
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
------------------------------------------------------------------------------
ALTERNATIVE B - Public Domain (www.unlicense.org)
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
software, either in source code form or as a compiled binary, for any purpose,
commercial or non-commercial, and by any means.
In jurisdictions that recognize copyright laws, the author or authors of this
software dedicate any and all copyright interest in the software to the public
domain. We make this dedication for the benefit of the public at large and to
the detriment of our heirs and successors. We intend this dedication to be an
overt act of relinquishment in perpetuity of all present and future rights to
this software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
------------------------------------------------------------------------------
*/