summaryrefslogtreecommitdiffstats
path: root/src/lex.cpp
blob: 70362a78096e11821254902649cb7c78b647f53d (plain)
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
/*
  Copyright (c) 2013-2015, Matthias Schiffer <mschiffer@universe-factory.net>
  All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:

    1. Redistributions of source code must retain the above copyright notice,
       this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright notice,
       this list of conditions and the following disclaimer in the documentation
       and/or other materials provided with the distribution.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/


#include "lex.hpp"

#include <cstdlib>


#define array_size(array) (sizeof(array)/sizeof((array)[0]))


namespace solar {


struct keyword_t {
	const char *keyword;
	int token;
};

/* the keyword list must be sorted */
static const keyword_t keywords[] = {
};

static int compare_keywords(const void *v1, const void *v2) {
	const keyword_t *k1 = static_cast<const keyword_t*>(v1), *k2 = static_cast<const keyword_t*>(v2);
	return std::strcmp(k1->keyword, k2->keyword);
}


bool lex_t::advance() {
	if (start > 0) {
		std::memmove(buffer, buffer+start, end - start);
		end -= start;
		start = 0;
	}

	if (end == sizeof(buffer))
		return false;

	size_t l = std::fread(buffer+end, 1, sizeof(buffer) - end, file);

	end += l;
	return l;
}

bool lex_t::next(bool move) {
	if (start + tok_len >= end)
		return false;

	if (current() == '\n') {
		loc.last_column = 0;
		loc.last_line++;
	}
	else {
		loc.last_column++;
	}

	if (move)
		start++;
	else
		tok_len++;


	if (start + tok_len >= end)
		return advance();

	return true;
}

void lex_t::consume(bool consume_needspace) {
	start += tok_len;
	tok_len = 0;

	needspace = consume_needspace;
}

int lex_t::io_error(parser_value_t *value) {
	value->error = "I/O error";
	return -1;
}

int lex_t::syntax_error(parser_value_t *value) {
	if (std::ferror(file))
		return io_error(value);

	value->error = "syntax error";
	return -1;
}

int lex_t::consume_comment(parser_value_t *value) {
	char prev = 0;

	while (next(true)) {
		if (prev == '*' && current() == '/') {
			next(true);
			consume(false);
			return 0;
		}

		prev = current();
	}

	if (std::ferror(file))
		return io_error(value);

	value->error = "unterminated block comment";
	return -1;
}

/*
int lex_t::unterminated_string(parser_value_t *value) {
	if (ferror(file))
		return io_error(value);

	value->error = "unterminated string";
	return -1;
}

int lex_t::lex_string(parser_value_t *value) {
	char *buf = NULL;
	size_t len = 1024;
	size_t pos = 0;

	if (needspace)
		return syntax_error(value);

	buf = static_cast<char*>(std::malloc(len));

	while (true) {
		if (!next(true)) {
			std::free(buf);
			return unterminated_string(value);
		}

		char cur = current();

		if (cur == '"')
			break;

		if (cur == '\\') {
			if (!next(true)) {
				free(buf);
				return unterminated_string(value);
			}

			cur = current();

			if (cur == '\n')
				continue;
		}

		if (pos >= len) {
			len *= 2;
			buf = static_cast<char*>(std::realloc(buf, len));
		}

		buf[pos++] = cur;
	}

	value->str = strndup(buf, pos);
	std::free(buf);

	next(true);
	consume(true);

	return TOK_STRING;
	}*/

int lex_t::lex_number(parser_value_t *value) {
	if (needspace)
		return syntax_error(value);

	while (next(false)) {
		char cur = current();

		if (cur >= '0' && cur <= '9')
			continue;

		if (cur == 'x' || (cur >= 'a' && cur <= 'f') || (cur >= 'A' && cur <= 'F'))
			continue;

		break;
	}

	char *endptr, *token = get_token();
	value->number = std::strtoull(token, &endptr, 0);

	bool ok = !*endptr;
	free(token);

	if (!ok)
		return syntax_error(value);

	consume(true);

	return TOK_UINT;
}

int lex_t::lex_keyword(parser_value_t *value) {
	if (needspace)
		return syntax_error(value);

	while (next(false)) {
		char cur = current();

		if (!((cur >= 'a' && cur <= 'z') || (cur >= '0' && cur <= '9') || cur == '-'))
			break;
	}

	char *token = get_token();
	const keyword_t key = { .keyword = token, .token = 0 };
	const keyword_t *ret = static_cast<const keyword_t*>(bsearch(&key, keywords, array_size(keywords), sizeof(keyword_t), compare_keywords));
	free(token);

	if (!ret)
		return syntax_error(value);

	consume(true);

	return ret->token;
}

int lex_t::unterminated_block(parser_value_t *value) {
	if (ferror(file))
		return io_error(value);

	value->error = "unterminated code block";
	return -1;
}

int lex_t::lex_block(parser_value_t *value) {
	size_t parens = 0;
	bool line_comment = false;
	bool block_comment = false;
	bool str = false;

	size_t pos = 0;
	size_t len = 1024;
	char *buf = static_cast<char*>(std::malloc(len));

	char prev = 0;

	while (true) {
		if (!next(true)) {
			std::free(buf);
			return unterminated_block(value);
		}

		char cur = current();

		if (line_comment) {
			if (cur == '\n' || cur == '\r')
				line_comment = false;
		}
		else if (block_comment) {
			if (prev == '*' && cur == '/')
				block_comment = false;
		}
		else if (str) {
			if (prev != '\\' && cur == '"')
				str = false;
		}
		else {
			if (cur == '{') {
				parens++;
			}
			else if (cur == '}') {
				if (!parens)
					break;

				parens--;
			}
			else if (cur == '"') {
				str = true;
			}
			else if (prev == '/' && cur == '/') {
				line_comment = true;
			}
			else if (prev == '/' && cur == '*') {
				block_comment = true;
			}
		}

		if (pos >= len) {
			len *= 2;
			buf = static_cast<char*>(std::realloc(buf, len));
		}

		buf[pos++] = cur;
		prev = cur;
	}

	value->str = strndup(buf, pos);
	std::free(buf);

	next(true);
	consume(true);

	return TOK_BLOCK;
}

int lex_t::lex_symbol(parser_value_t *value, bool terminal) {
	if (needspace)
		return syntax_error(value);

	while (next(false)) {
		char cur = current();

		switch (cur) {
		case 'A' ... 'Z':
			if (!terminal)
				break;

			continue;

		case 'a' ... 'z':
			if (terminal)
				break;

			continue;

		case '0' ... '9':
		case '_':
			continue;
		}

		break;
	}

	value->str = get_token();
	return terminal ? TOK_TERM : TOK_NONTERM;
}

int lex_t::lex(parser_value_t *value) {
	int token;

	while (end > start) {
		loc.first_line = loc.last_line;
		loc.first_column = loc.last_column+1;

		switch (current()) {
		case ' ':
		case '\n':
		case '\t':
		case '\r':
			next(true);
			consume(false);
			continue;

		case ';':
		case ':':
		case '|':
		case '=':
			token = current();
			next(true);
			consume(false);
			return token;

		case '/':
			if (!next(true))
				return syntax_error(value);

			if (current() == '*') {
				token = consume_comment(value);
				if (token)
					return token;

				continue;
			}

			if (current() != '/')
				return syntax_error(value);

			while (next(true)) {
				if (current() == '\n')
					break;
			}

			next(true);
			consume(false);
			continue;

		case '\'':
			if (!next(true))
				return syntax_error(value);

			value->number = current();

			if (!next(true) || current() != '\'')
				return syntax_error(value);

			next(true);

			consume(false);

			return TOK_CHAR;

		case '{':
			return lex_block(value);

			//case '"':
			//return lex_string(value);

		case '0' ... '9':
			return lex_number(value);

		case 'a' ... 'z':
			return lex_symbol(value, false);

		case 'A' ... 'Z':
			return lex_symbol(value, true);

		default:
			return syntax_error(value);
		}
	}

	if (ferror(file))
		return io_error(value);

	return 0;
}

}