xref: /aosp_15_r20/external/coreboot/util/kconfig/lexer.l (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2002 Roman Zippel <[email protected]>
4  */
5 %option nostdinit noyywrap never-interactive full ecs
6 %option 8bit nodefault yylineno
7 %x ASSIGN_VAL HELP STRING
8 %{
9 
10 #include <assert.h>
11 #include <glob.h>
12 #include <limits.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 
17 #include "lkc.h"
18 #include "parser.tab.h"
19 
20 #define YY_DECL		static int yylex1(void)
21 
22 #define START_STRSIZE	16
23 
24 static struct {
25 	struct file *file;
26 	int lineno;
27 } current_pos;
28 
29 static int prev_prev_token = T_EOL;
30 static int prev_token = T_EOL;
31 static char *text;
32 static int text_size, text_asize;
33 
34 struct buffer {
35 	struct buffer *parent;
36 	YY_BUFFER_STATE state;
37 };
38 
39 static struct buffer *current_buf;
40 
41 static int last_ts, first_ts;
42 
43 static char *expand_token(const char *in, size_t n);
44 static void append_expanded_string(const char *in);
45 static void zconf_endhelp(void);
46 static void zconf_endfile(void);
47 
new_string(void)48 static void new_string(void)
49 {
50 	text = xmalloc(START_STRSIZE);
51 	text_asize = START_STRSIZE;
52 	text_size = 0;
53 	*text = 0;
54 }
55 
append_string(const char * str,int size)56 static void append_string(const char *str, int size)
57 {
58 	int new_size = text_size + size + 1;
59 	if (new_size > text_asize) {
60 		new_size += START_STRSIZE - 1;
61 		new_size &= -START_STRSIZE;
62 		text = xrealloc(text, new_size);
63 		text_asize = new_size;
64 	}
65 	memcpy(text + text_size, str, size);
66 	text_size += size;
67 	text[text_size] = 0;
68 }
69 
alloc_string(const char * str,int size)70 static void alloc_string(const char *str, int size)
71 {
72 	text = xmalloc(size + 1);
73 	memcpy(text, str, size);
74 	text[size] = 0;
75 }
76 
warn_ignored_character(char chr)77 static void warn_ignored_character(char chr)
78 {
79 	fprintf(stderr,
80 	        "%s:%d:warning: ignoring unsupported character '%c'\n",
81 	        current_file->name, yylineno, chr);
82 }
83 %}
84 
85 n	[A-Za-z0-9_-]
86 
87 %%
88 	char open_quote = 0;
89 
90 #.*			/* ignore comment */
91 [ \t]*			/* whitespaces */
92 \\\n			/* escaped new line */
93 \n			return T_EOL;
94 "bool"			return T_BOOL;
95 "choice"		return T_CHOICE;
96 "comment"		return T_COMMENT;
97 "config"		return T_CONFIG;
98 "def_bool"		return T_DEF_BOOL;
99 "def_tristate"		return T_DEF_TRISTATE;
100 "default"		return T_DEFAULT;
101 "depends"		return T_DEPENDS;
102 "endchoice"		return T_ENDCHOICE;
103 "endif"			return T_ENDIF;
104 "endmenu"		return T_ENDMENU;
105 "help"			return T_HELP;
106 "hex"			return T_HEX;
107 "if"			return T_IF;
108 "imply"			return T_IMPLY;
109 "int"			return T_INT;
110 "mainmenu"		return T_MAINMENU;
111 "menu"			return T_MENU;
112 "menuconfig"		return T_MENUCONFIG;
113 "modules"		return T_MODULES;
114 "on"			return T_ON;
115 "optional"		return T_OPTIONAL;
116 "prompt"		return T_PROMPT;
117 "range"			return T_RANGE;
118 "select"		return T_SELECT;
119 "source"		return T_SOURCE;
120 "string"		return T_STRING;
121 "tristate"		return T_TRISTATE;
122 "visible"		return T_VISIBLE;
123 "||"			return T_OR;
124 "&&"			return T_AND;
125 "="			return T_EQUAL;
126 "!="			return T_UNEQUAL;
127 "<"			return T_LESS;
128 "<="			return T_LESS_EQUAL;
129 ">"			return T_GREATER;
130 ">="			return T_GREATER_EQUAL;
131 "!"			return T_NOT;
132 "("			return T_OPEN_PAREN;
133 ")"			return T_CLOSE_PAREN;
134 ":="			return T_COLON_EQUAL;
135 "+="			return T_PLUS_EQUAL;
136 \"|\'			{
137 				open_quote = yytext[0];
138 				new_string();
139 				BEGIN(STRING);
140 			}
141 {n}+			{
142 				alloc_string(yytext, yyleng);
143 				yylval.string = text;
144 				return T_WORD;
145 			}
146 ({n}|$)+		{
147 				/* this token includes at least one '$' */
148 				yylval.string = expand_token(yytext, yyleng);
149 				if (strlen(yylval.string))
150 					return T_WORD;
151 				free(yylval.string);
152 			}
153 .			warn_ignored_character(*yytext);
154 
155 <ASSIGN_VAL>{
156 	[^[:blank:]\n]+.*	{
157 		alloc_string(yytext, yyleng);
158 		yylval.string = text;
159 		return T_ASSIGN_VAL;
160 	}
161 	\n	{ BEGIN(INITIAL); return T_EOL; }
162 	.
163 }
164 
165 <STRING>{
166 	"$".*	append_expanded_string(yytext);
167 	[^$'"\\\n]+	{
168 		append_string(yytext, yyleng);
169 	}
170 	\\.?	{
171 		append_string(yytext + 1, yyleng - 1);
172 	}
173 	\'|\"	{
174 		if (open_quote == yytext[0]) {
175 			BEGIN(INITIAL);
176 			yylval.string = text;
177 			return T_WORD_QUOTE;
178 		} else
179 			append_string(yytext, 1);
180 	}
181 	\n	{
182 		fprintf(stderr,
183 			"%s:%d:warning: multi-line strings not supported\n",
184 			zconf_curname(), zconf_lineno());
185 		unput('\n');
186 		BEGIN(INITIAL);
187 		yylval.string = text;
188 		return T_WORD_QUOTE;
189 	}
190 	<<EOF>>	{
191 		BEGIN(INITIAL);
192 		yylval.string = text;
193 		return T_WORD_QUOTE;
194 	}
195 }
196 
197 <HELP>{
198 	[ \t]+	{
199 		int ts, i;
200 
201 		ts = 0;
202 		for (i = 0; i < yyleng; i++) {
203 			if (yytext[i] == '\t')
204 				ts = (ts & ~7) + 8;
205 			else
206 				ts++;
207 		}
208 		last_ts = ts;
209 		if (first_ts) {
210 			if (ts < first_ts) {
211 				zconf_endhelp();
212 				return T_HELPTEXT;
213 			}
214 			ts -= first_ts;
215 			while (ts > 8) {
216 				append_string("        ", 8);
217 				ts -= 8;
218 			}
219 			append_string("        ", ts);
220 		}
221 	}
222 	[ \t]*\n/[^ \t\n] {
223 		zconf_endhelp();
224 		return T_HELPTEXT;
225 	}
226 	[ \t]*\n	{
227 		append_string("\n", 1);
228 	}
229 	[^ \t\n].* {
230 		while (yyleng) {
231 			if ((yytext[yyleng-1] != ' ') && (yytext[yyleng-1] != '\t'))
232 				break;
233 			yyleng--;
234 		}
235 		append_string(yytext, yyleng);
236 		if (!first_ts)
237 			first_ts = last_ts;
238 	}
239 	<<EOF>>	{
240 		zconf_endhelp();
241 		return T_HELPTEXT;
242 	}
243 }
244 
245 <<EOF>>	{
246 	BEGIN(INITIAL);
247 
248 	if (prev_token != T_EOL && prev_token != T_HELPTEXT)
249 		fprintf(stderr, "%s:%d:warning: no new line at end of file\n",
250 			current_file->name, yylineno);
251 
252 	if (current_file) {
253 		zconf_endfile();
254 		return T_EOL;
255 	}
256 	fclose(yyin);
257 	yyterminate();
258 }
259 
260 %%
261 
262 /* second stage lexer */
263 int yylex(void)
264 {
265 	int token;
266 
267 repeat:
268 	token = yylex1();
269 
270 	if (prev_token == T_EOL || prev_token == T_HELPTEXT) {
271 		if (token == T_EOL) {
272 			/* Do not pass unneeded T_EOL to the parser. */
273 			goto repeat;
274 		} else {
275 			/*
276 			 * For the parser, update file/lineno at the first token
277 			 * of each statement. Generally, \n is a statement
278 			 * terminator in Kconfig, but it is not always true
279 			 * because \n could be escaped by a backslash.
280 			 */
281 			current_pos.file = current_file;
282 			current_pos.lineno = yylineno;
283 		}
284 	}
285 
286 	if (prev_prev_token == T_EOL && prev_token == T_WORD &&
287 	    (token == T_EQUAL || token == T_COLON_EQUAL || token == T_PLUS_EQUAL))
288 		BEGIN(ASSIGN_VAL);
289 
290 	prev_prev_token = prev_token;
291 	prev_token = token;
292 
293 	return token;
294 }
295 
296 static char *expand_token(const char *in, size_t n)
297 {
298 	char *out;
299 	int c;
300 	char c2;
301 	const char *rest, *end;
302 
303 	new_string();
304 	append_string(in, n);
305 
306 	/* get the whole line because we do not know the end of token. */
307 	while ((c = input()) != EOF) {
308 		if (c == '\n') {
309 			unput(c);
310 			break;
311 		}
312 		c2 = c;
313 		append_string(&c2, 1);
314 	}
315 
316 	rest = text;
317 	out = expand_one_token(&rest);
318 
319 	/* push back unused characters to the input stream */
320 	end = rest + strlen(rest);
321 	while (end > rest)
322 		unput(*--end);
323 
324 	free(text);
325 
326 	return out;
327 }
328 
329 static void append_expanded_string(const char *str)
330 {
331 	const char *end;
332 	char *res;
333 
334 	str++;
335 
336 	res = expand_dollar(&str);
337 
338 	/* push back unused characters to the input stream */
339 	end = str + strlen(str);
340 	while (end > str)
341 		unput(*--end);
342 
343 	append_string(res, strlen(res));
344 
345 	free(res);
346 }
347 
348 void zconf_starthelp(void)
349 {
350 	new_string();
351 	last_ts = first_ts = 0;
352 	BEGIN(HELP);
353 }
354 
355 static void zconf_endhelp(void)
356 {
357 	yylval.string = text;
358 	BEGIN(INITIAL);
359 }
360 
361 
362 /*
363  * Try to open specified file with following names:
364  * ./name
365  * $(srctree)/name
366  * The latter is used when srctree is separate from objtree
367  * when compiling the kernel.
368  * Return NULL if file is not found.
369  */
370 FILE *zconf_fopen(const char *name)
371 {
372 	char *env, fullname[PATH_MAX+1];
373 	FILE *f;
374 
375 	f = fopen(name, "r");
376 	if (!f && name != NULL && name[0] != '/') {
377 		env = getenv(SRCTREE);
378 		if (env) {
379 			snprintf(fullname, sizeof(fullname),
380 				 "%s/%s", env, name);
381 			f = fopen(fullname, "r");
382 		}
383 	}
384 	return f;
385 }
386 
387 void zconf_initscan(const char *name)
388 {
389 	yyin = zconf_fopen(name);
390 	if (!yyin) {
391 		fprintf(stderr, "can't find file %s\n", name);
392 		exit(1);
393 	}
394 
395 	current_buf = xmalloc(sizeof(*current_buf));
396 	memset(current_buf, 0, sizeof(*current_buf));
397 
398 	current_file = file_lookup(name);
399 	yylineno = 1;
400 }
401 
402 void zconf_nextfile(const char *name)
403 {
404 	struct file *iter;
405 	struct file *file = file_lookup(name);
406 	struct buffer *buf = xmalloc(sizeof(*buf));
407 	memset(buf, 0, sizeof(*buf));
408 
409 	current_buf->state = YY_CURRENT_BUFFER;
410 	yyin = zconf_fopen(file->name);
411 	if (!yyin) {
412 		fprintf(stderr, "%s:%d: can't open file \"%s\"\n",
413 			zconf_curname(), zconf_lineno(), file->name);
414 		exit(1);
415 	}
416 	yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
417 	buf->parent = current_buf;
418 	current_buf = buf;
419 
420 	current_file->lineno = yylineno;
421 	file->parent = current_file;
422 
423 	for (iter = current_file; iter; iter = iter->parent) {
424 		if (!strcmp(iter->name, file->name)) {
425 			fprintf(stderr,
426 				"Recursive inclusion detected.\n"
427 				"Inclusion path:\n"
428 				"  current file : %s\n", file->name);
429 			iter = file;
430 			do {
431 				iter = iter->parent;
432 				fprintf(stderr, "  included from: %s:%d\n",
433 					iter->name, iter->lineno - 1);
434 			} while (strcmp(iter->name, file->name));
435 			exit(1);
436 		}
437 	}
438 
439 	yylineno = 1;
440 	current_file = file;
441 }
442 
443 void zconf_nextfiles(const char *wildcard)
444 {
445 	glob_t g;
446 	char **w;
447 	int i;
448 
449 	if (glob(wildcard, 0, NULL, &g) != 0) {
450 		return;
451 	}
452 	if (g.gl_pathv == NULL) {
453 		globfree(&g);
454 		return;
455 	}
456 
457 	/* working through files backwards, since
458 	 * we're first pushing them on a stack
459 	 * before actually handling them.
460 	 */
461 	for (i = g.gl_pathc; i > 0; i--) {
462 		w = &g.gl_pathv[i - 1];
463 		zconf_nextfile(*w);
464 	}
465 
466 	globfree(&g);
467 }
468 
469 static void zconf_endfile(void)
470 {
471 	struct buffer *parent;
472 
473 	current_file = current_file->parent;
474 	if (current_file)
475 		yylineno = current_file->lineno;
476 
477 	parent = current_buf->parent;
478 	if (parent) {
479 		fclose(yyin);
480 		yy_delete_buffer(YY_CURRENT_BUFFER);
481 		yy_switch_to_buffer(parent->state);
482 	}
483 	free(current_buf);
484 	current_buf = parent;
485 }
486 
487 int zconf_lineno(void)
488 {
489 	return current_pos.lineno;
490 }
491 
492 const char *zconf_curname(void)
493 {
494 	return current_pos.file ? current_pos.file->name : "<none>";
495 }
496