1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // |
3 | // Copyright (C) 2018 Masahiro Yamada <yamada.masahiro@socionext.com> |
4 | |
5 | #include <ctype.h> |
6 | #include <stdarg.h> |
7 | #include <stdbool.h> |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <string.h> |
11 | |
12 | #include "array_size.h" |
13 | #include "internal.h" |
14 | #include "list.h" |
15 | #include "lkc.h" |
16 | #include "preprocess.h" |
17 | |
18 | static char *expand_string_with_args(const char *in, int argc, char *argv[]); |
19 | static char *expand_string(const char *in); |
20 | |
21 | static void __attribute__((noreturn)) pperror(const char *format, ...) |
22 | { |
23 | va_list ap; |
24 | |
25 | fprintf(stderr, format: "%s:%d: " , cur_filename, yylineno); |
26 | va_start(ap, format); |
27 | vfprintf(stderr, format: format, arg: ap); |
28 | va_end(ap); |
29 | fprintf(stderr, format: "\n" ); |
30 | |
31 | exit(status: 1); |
32 | } |
33 | |
34 | /* |
35 | * Environment variables |
36 | */ |
37 | static LIST_HEAD(env_list); |
38 | |
39 | struct env { |
40 | char *name; |
41 | char *value; |
42 | struct list_head node; |
43 | }; |
44 | |
45 | static void env_add(const char *name, const char *value) |
46 | { |
47 | struct env *e; |
48 | |
49 | e = xmalloc(size: sizeof(*e)); |
50 | e->name = xstrdup(s: name); |
51 | e->value = xstrdup(s: value); |
52 | |
53 | list_add_tail(new: &e->node, head: &env_list); |
54 | } |
55 | |
56 | static void env_del(struct env *e) |
57 | { |
58 | list_del(entry: &e->node); |
59 | free(ptr: e->name); |
60 | free(ptr: e->value); |
61 | free(ptr: e); |
62 | } |
63 | |
64 | /* The returned pointer must be freed when done */ |
65 | static char *env_expand(const char *name) |
66 | { |
67 | struct env *e; |
68 | const char *value; |
69 | |
70 | if (!*name) |
71 | return NULL; |
72 | |
73 | list_for_each_entry(e, &env_list, node) { |
74 | if (!strcmp(s1: name, s2: e->name)) |
75 | return xstrdup(s: e->value); |
76 | } |
77 | |
78 | value = getenv(name: name); |
79 | if (!value) |
80 | return NULL; |
81 | |
82 | /* |
83 | * We need to remember all referenced environment variables. |
84 | * They will be written out to include/config/auto.conf.cmd |
85 | */ |
86 | env_add(name, value); |
87 | |
88 | return xstrdup(s: value); |
89 | } |
90 | |
91 | void env_write_dep(struct gstr *s) |
92 | { |
93 | struct env *e, *tmp; |
94 | |
95 | list_for_each_entry_safe(e, tmp, &env_list, node) { |
96 | str_printf(gs: s, |
97 | fmt: "\n" |
98 | "ifneq \"$(%s)\" \"%s\"\n" |
99 | "$(autoconfig): FORCE\n" |
100 | "endif\n" , |
101 | e->name, e->value); |
102 | env_del(e); |
103 | } |
104 | } |
105 | |
106 | /* |
107 | * Built-in functions |
108 | */ |
109 | struct function { |
110 | const char *name; |
111 | unsigned int min_args; |
112 | unsigned int max_args; |
113 | char *(*func)(int argc, char *argv[]); |
114 | }; |
115 | |
116 | static char *do_error_if(int argc, char *argv[]) |
117 | { |
118 | if (!strcmp(s1: argv[0], s2: "y" )) |
119 | pperror(format: "%s" , argv[1]); |
120 | |
121 | return xstrdup(s: "" ); |
122 | } |
123 | |
124 | static char *do_filename(int argc, char *argv[]) |
125 | { |
126 | return xstrdup(s: cur_filename); |
127 | } |
128 | |
129 | static char *do_info(int argc, char *argv[]) |
130 | { |
131 | printf(format: "%s\n" , argv[0]); |
132 | |
133 | return xstrdup(s: "" ); |
134 | } |
135 | |
136 | static char *do_lineno(int argc, char *argv[]) |
137 | { |
138 | char buf[16]; |
139 | |
140 | sprintf(s: buf, format: "%d" , yylineno); |
141 | |
142 | return xstrdup(s: buf); |
143 | } |
144 | |
145 | static char *do_shell(int argc, char *argv[]) |
146 | { |
147 | FILE *p; |
148 | char buf[4096]; |
149 | char *cmd; |
150 | size_t nread; |
151 | int i; |
152 | |
153 | cmd = argv[0]; |
154 | |
155 | p = popen(command: cmd, modes: "r" ); |
156 | if (!p) { |
157 | perror(s: cmd); |
158 | exit(status: 1); |
159 | } |
160 | |
161 | nread = fread(ptr: buf, size: 1, n: sizeof(buf), stream: p); |
162 | if (nread == sizeof(buf)) |
163 | nread--; |
164 | |
165 | /* remove trailing new lines */ |
166 | while (nread > 0 && buf[nread - 1] == '\n') |
167 | nread--; |
168 | |
169 | buf[nread] = 0; |
170 | |
171 | /* replace a new line with a space */ |
172 | for (i = 0; i < nread; i++) { |
173 | if (buf[i] == '\n') |
174 | buf[i] = ' '; |
175 | } |
176 | |
177 | if (pclose(stream: p) == -1) { |
178 | perror(s: cmd); |
179 | exit(status: 1); |
180 | } |
181 | |
182 | return xstrdup(s: buf); |
183 | } |
184 | |
185 | static char *do_warning_if(int argc, char *argv[]) |
186 | { |
187 | if (!strcmp(s1: argv[0], s2: "y" )) |
188 | fprintf(stderr, format: "%s:%d: %s\n" , cur_filename, yylineno, argv[1]); |
189 | |
190 | return xstrdup(s: "" ); |
191 | } |
192 | |
193 | static const struct function function_table[] = { |
194 | /* Name MIN MAX Function */ |
195 | { "error-if" , 2, 2, do_error_if }, |
196 | { "filename" , 0, 0, do_filename }, |
197 | { "info" , 1, 1, do_info }, |
198 | { "lineno" , 0, 0, do_lineno }, |
199 | { "shell" , 1, 1, do_shell }, |
200 | { "warning-if" , 2, 2, do_warning_if }, |
201 | }; |
202 | |
203 | #define FUNCTION_MAX_ARGS 16 |
204 | |
205 | static char *function_expand(const char *name, int argc, char *argv[]) |
206 | { |
207 | const struct function *f; |
208 | int i; |
209 | |
210 | for (i = 0; i < ARRAY_SIZE(function_table); i++) { |
211 | f = &function_table[i]; |
212 | if (strcmp(s1: f->name, s2: name)) |
213 | continue; |
214 | |
215 | if (argc < f->min_args) |
216 | pperror(format: "too few function arguments passed to '%s'" , |
217 | name); |
218 | |
219 | if (argc > f->max_args) |
220 | pperror(format: "too many function arguments passed to '%s'" , |
221 | name); |
222 | |
223 | return f->func(argc, argv); |
224 | } |
225 | |
226 | return NULL; |
227 | } |
228 | |
229 | /* |
230 | * Variables (and user-defined functions) |
231 | */ |
232 | static LIST_HEAD(variable_list); |
233 | |
234 | struct variable { |
235 | char *name; |
236 | char *value; |
237 | enum variable_flavor flavor; |
238 | int exp_count; |
239 | struct list_head node; |
240 | }; |
241 | |
242 | static struct variable *variable_lookup(const char *name) |
243 | { |
244 | struct variable *v; |
245 | |
246 | list_for_each_entry(v, &variable_list, node) { |
247 | if (!strcmp(s1: name, s2: v->name)) |
248 | return v; |
249 | } |
250 | |
251 | return NULL; |
252 | } |
253 | |
254 | static char *variable_expand(const char *name, int argc, char *argv[]) |
255 | { |
256 | struct variable *v; |
257 | char *res; |
258 | |
259 | v = variable_lookup(name); |
260 | if (!v) |
261 | return NULL; |
262 | |
263 | if (argc == 0 && v->exp_count) |
264 | pperror(format: "Recursive variable '%s' references itself (eventually)" , |
265 | name); |
266 | |
267 | if (v->exp_count > 1000) |
268 | pperror(format: "Too deep recursive expansion" ); |
269 | |
270 | v->exp_count++; |
271 | |
272 | if (v->flavor == VAR_RECURSIVE) |
273 | res = expand_string_with_args(in: v->value, argc, argv); |
274 | else |
275 | res = xstrdup(s: v->value); |
276 | |
277 | v->exp_count--; |
278 | |
279 | return res; |
280 | } |
281 | |
282 | void variable_add(const char *name, const char *value, |
283 | enum variable_flavor flavor) |
284 | { |
285 | struct variable *v; |
286 | char *new_value; |
287 | bool append = false; |
288 | |
289 | v = variable_lookup(name); |
290 | if (v) { |
291 | /* For defined variables, += inherits the existing flavor */ |
292 | if (flavor == VAR_APPEND) { |
293 | flavor = v->flavor; |
294 | append = true; |
295 | } else { |
296 | free(ptr: v->value); |
297 | } |
298 | } else { |
299 | /* For undefined variables, += assumes the recursive flavor */ |
300 | if (flavor == VAR_APPEND) |
301 | flavor = VAR_RECURSIVE; |
302 | |
303 | v = xmalloc(size: sizeof(*v)); |
304 | v->name = xstrdup(s: name); |
305 | v->exp_count = 0; |
306 | list_add_tail(new: &v->node, head: &variable_list); |
307 | } |
308 | |
309 | v->flavor = flavor; |
310 | |
311 | if (flavor == VAR_SIMPLE) |
312 | new_value = expand_string(in: value); |
313 | else |
314 | new_value = xstrdup(s: value); |
315 | |
316 | if (append) { |
317 | v->value = xrealloc(p: v->value, |
318 | size: strlen(s: v->value) + strlen(s: new_value) + 2); |
319 | strcat(dest: v->value, src: " " ); |
320 | strcat(dest: v->value, src: new_value); |
321 | free(ptr: new_value); |
322 | } else { |
323 | v->value = new_value; |
324 | } |
325 | } |
326 | |
327 | static void variable_del(struct variable *v) |
328 | { |
329 | list_del(entry: &v->node); |
330 | free(ptr: v->name); |
331 | free(ptr: v->value); |
332 | free(ptr: v); |
333 | } |
334 | |
335 | void variable_all_del(void) |
336 | { |
337 | struct variable *v, *tmp; |
338 | |
339 | list_for_each_entry_safe(v, tmp, &variable_list, node) |
340 | variable_del(v); |
341 | } |
342 | |
343 | /* |
344 | * Evaluate a clause with arguments. argc/argv are arguments from the upper |
345 | * function call. |
346 | * |
347 | * Returned string must be freed when done |
348 | */ |
349 | static char *eval_clause(const char *str, size_t len, int argc, char *argv[]) |
350 | { |
351 | char *tmp, *name, *res, *endptr, *prev, *p; |
352 | int new_argc = 0; |
353 | char *new_argv[FUNCTION_MAX_ARGS]; |
354 | int nest = 0; |
355 | int i; |
356 | unsigned long n; |
357 | |
358 | tmp = xstrndup(s: str, n: len); |
359 | |
360 | /* |
361 | * If variable name is '1', '2', etc. It is generally an argument |
362 | * from a user-function call (i.e. local-scope variable). If not |
363 | * available, then look-up global-scope variables. |
364 | */ |
365 | n = strtoul(nptr: tmp, endptr: &endptr, base: 10); |
366 | if (!*endptr && n > 0 && n <= argc) { |
367 | res = xstrdup(s: argv[n - 1]); |
368 | goto free_tmp; |
369 | } |
370 | |
371 | prev = p = tmp; |
372 | |
373 | /* |
374 | * Split into tokens |
375 | * The function name and arguments are separated by a comma. |
376 | * For example, if the function call is like this: |
377 | * $(foo,$(x),$(y)) |
378 | * |
379 | * The input string for this helper should be: |
380 | * foo,$(x),$(y) |
381 | * |
382 | * and split into: |
383 | * new_argv[0] = 'foo' |
384 | * new_argv[1] = '$(x)' |
385 | * new_argv[2] = '$(y)' |
386 | */ |
387 | while (*p) { |
388 | if (nest == 0 && *p == ',') { |
389 | *p = 0; |
390 | if (new_argc >= FUNCTION_MAX_ARGS) |
391 | pperror(format: "too many function arguments" ); |
392 | new_argv[new_argc++] = prev; |
393 | prev = p + 1; |
394 | } else if (*p == '(') { |
395 | nest++; |
396 | } else if (*p == ')') { |
397 | nest--; |
398 | } |
399 | |
400 | p++; |
401 | } |
402 | |
403 | if (new_argc >= FUNCTION_MAX_ARGS) |
404 | pperror(format: "too many function arguments" ); |
405 | new_argv[new_argc++] = prev; |
406 | |
407 | /* |
408 | * Shift arguments |
409 | * new_argv[0] represents a function name or a variable name. Put it |
410 | * into 'name', then shift the rest of the arguments. This simplifies |
411 | * 'const' handling. |
412 | */ |
413 | name = expand_string_with_args(in: new_argv[0], argc, argv); |
414 | new_argc--; |
415 | for (i = 0; i < new_argc; i++) |
416 | new_argv[i] = expand_string_with_args(in: new_argv[i + 1], |
417 | argc, argv); |
418 | |
419 | /* Search for variables */ |
420 | res = variable_expand(name, argc: new_argc, argv: new_argv); |
421 | if (res) |
422 | goto free; |
423 | |
424 | /* Look for built-in functions */ |
425 | res = function_expand(name, argc: new_argc, argv: new_argv); |
426 | if (res) |
427 | goto free; |
428 | |
429 | /* Last, try environment variable */ |
430 | if (new_argc == 0) { |
431 | res = env_expand(name); |
432 | if (res) |
433 | goto free; |
434 | } |
435 | |
436 | res = xstrdup(s: "" ); |
437 | free: |
438 | for (i = 0; i < new_argc; i++) |
439 | free(ptr: new_argv[i]); |
440 | free(ptr: name); |
441 | free_tmp: |
442 | free(ptr: tmp); |
443 | |
444 | return res; |
445 | } |
446 | |
447 | /* |
448 | * Expand a string that follows '$' |
449 | * |
450 | * For example, if the input string is |
451 | * ($(FOO)$($(BAR)))$(BAZ) |
452 | * this helper evaluates |
453 | * $($(FOO)$($(BAR))) |
454 | * and returns a new string containing the expansion (note that the string is |
455 | * recursively expanded), also advancing 'str' to point to the next character |
456 | * after the corresponding closing parenthesis, in this case, *str will be |
457 | * $(BAR) |
458 | */ |
459 | static char *expand_dollar_with_args(const char **str, int argc, char *argv[]) |
460 | { |
461 | const char *p = *str; |
462 | const char *q; |
463 | int nest = 0; |
464 | |
465 | /* |
466 | * In Kconfig, variable/function references always start with "$(". |
467 | * Neither single-letter variables as in $A nor curly braces as in ${CC} |
468 | * are supported. '$' not followed by '(' loses its special meaning. |
469 | */ |
470 | if (*p != '(') { |
471 | *str = p; |
472 | return xstrdup(s: "$" ); |
473 | } |
474 | |
475 | p++; |
476 | q = p; |
477 | while (*q) { |
478 | if (*q == '(') { |
479 | nest++; |
480 | } else if (*q == ')') { |
481 | if (nest-- == 0) |
482 | break; |
483 | } |
484 | q++; |
485 | } |
486 | |
487 | if (!*q) |
488 | pperror(format: "unterminated reference to '%s': missing ')'" , p); |
489 | |
490 | /* Advance 'str' to after the expanded initial portion of the string */ |
491 | *str = q + 1; |
492 | |
493 | return eval_clause(str: p, len: q - p, argc, argv); |
494 | } |
495 | |
496 | char *expand_dollar(const char **str) |
497 | { |
498 | return expand_dollar_with_args(str, argc: 0, NULL); |
499 | } |
500 | |
501 | static char *__expand_string(const char **str, bool (*is_end)(char c), |
502 | int argc, char *argv[]) |
503 | { |
504 | const char *in, *p; |
505 | char *expansion, *out; |
506 | size_t in_len, out_len; |
507 | |
508 | out = xmalloc(size: 1); |
509 | *out = 0; |
510 | out_len = 1; |
511 | |
512 | p = in = *str; |
513 | |
514 | while (1) { |
515 | if (*p == '$') { |
516 | in_len = p - in; |
517 | p++; |
518 | expansion = expand_dollar_with_args(str: &p, argc, argv); |
519 | out_len += in_len + strlen(s: expansion); |
520 | out = xrealloc(p: out, size: out_len); |
521 | strncat(dest: out, src: in, n: in_len); |
522 | strcat(dest: out, src: expansion); |
523 | free(ptr: expansion); |
524 | in = p; |
525 | continue; |
526 | } |
527 | |
528 | if (is_end(*p)) |
529 | break; |
530 | |
531 | p++; |
532 | } |
533 | |
534 | in_len = p - in; |
535 | out_len += in_len; |
536 | out = xrealloc(p: out, size: out_len); |
537 | strncat(dest: out, src: in, n: in_len); |
538 | |
539 | /* Advance 'str' to the end character */ |
540 | *str = p; |
541 | |
542 | return out; |
543 | } |
544 | |
545 | static bool is_end_of_str(char c) |
546 | { |
547 | return !c; |
548 | } |
549 | |
550 | /* |
551 | * Expand variables and functions in the given string. Undefined variables |
552 | * expand to an empty string. |
553 | * The returned string must be freed when done. |
554 | */ |
555 | static char *expand_string_with_args(const char *in, int argc, char *argv[]) |
556 | { |
557 | return __expand_string(str: &in, is_end: is_end_of_str, argc, argv); |
558 | } |
559 | |
560 | static char *expand_string(const char *in) |
561 | { |
562 | return expand_string_with_args(in, argc: 0, NULL); |
563 | } |
564 | |
565 | static bool is_end_of_token(char c) |
566 | { |
567 | return !(isalnum(c) || c == '_' || c == '-'); |
568 | } |
569 | |
570 | /* |
571 | * Expand variables in a token. The parsing stops when a token separater |
572 | * (in most cases, it is a whitespace) is encountered. 'str' is updated to |
573 | * point to the next character. |
574 | * |
575 | * The returned string must be freed when done. |
576 | */ |
577 | char *expand_one_token(const char **str) |
578 | { |
579 | return __expand_string(str, is_end: is_end_of_token, argc: 0, NULL); |
580 | } |
581 | |