Martin Roth | be08c1d | 2024-02-16 09:12:33 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Patrick Georgi | 53ea1d4 | 2019-11-22 16:55:58 +0100 | [diff] [blame] | 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 "list.h" |
| 13 | #include "lkc.h" |
| 14 | |
| 15 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) |
| 16 | |
| 17 | static char *expand_string_with_args(const char *in, int argc, char *argv[]); |
| 18 | static char *expand_string(const char *in); |
| 19 | |
| 20 | static void __attribute__((noreturn)) pperror(const char *format, ...) |
| 21 | { |
| 22 | va_list ap; |
| 23 | |
| 24 | fprintf(stderr, "%s:%d: ", current_file->name, yylineno); |
| 25 | va_start(ap, format); |
| 26 | vfprintf(stderr, format, ap); |
| 27 | va_end(ap); |
| 28 | fprintf(stderr, "\n"); |
| 29 | |
| 30 | exit(1); |
| 31 | } |
| 32 | |
| 33 | /* |
| 34 | * Environment variables |
| 35 | */ |
| 36 | static LIST_HEAD(env_list); |
| 37 | |
| 38 | struct env { |
| 39 | char *name; |
| 40 | char *value; |
| 41 | struct list_head node; |
| 42 | }; |
| 43 | |
| 44 | static void env_add(const char *name, const char *value) |
| 45 | { |
| 46 | struct env *e; |
| 47 | |
| 48 | e = xmalloc(sizeof(*e)); |
| 49 | e->name = xstrdup(name); |
| 50 | e->value = xstrdup(value); |
| 51 | |
| 52 | list_add_tail(&e->node, &env_list); |
| 53 | } |
| 54 | |
| 55 | static void env_del(struct env *e) |
| 56 | { |
| 57 | list_del(&e->node); |
| 58 | free(e->name); |
| 59 | free(e->value); |
| 60 | free(e); |
| 61 | } |
| 62 | |
| 63 | /* The returned pointer must be freed when done */ |
| 64 | static char *env_expand(const char *name) |
| 65 | { |
| 66 | struct env *e; |
| 67 | const char *value; |
| 68 | |
| 69 | if (!*name) |
| 70 | return NULL; |
| 71 | |
| 72 | list_for_each_entry(e, &env_list, node) { |
| 73 | if (!strcmp(name, e->name)) |
| 74 | return xstrdup(e->value); |
| 75 | } |
| 76 | |
| 77 | value = getenv(name); |
| 78 | if (!value) |
| 79 | return NULL; |
| 80 | |
| 81 | /* |
| 82 | * We need to remember all referenced environment variables. |
| 83 | * They will be written out to include/config/auto.conf.cmd |
| 84 | */ |
| 85 | env_add(name, value); |
| 86 | |
| 87 | return xstrdup(value); |
| 88 | } |
| 89 | |
| 90 | void env_write_dep(FILE *f, const char *autoconfig_name) |
| 91 | { |
| 92 | struct env *e, *tmp; |
| 93 | |
| 94 | list_for_each_entry_safe(e, tmp, &env_list, node) { |
| 95 | fprintf(f, "ifneq \"$(%s)\" \"%s\"\n", e->name, e->value); |
| 96 | fprintf(f, "%s: FORCE\n", autoconfig_name); |
| 97 | fprintf(f, "endif\n"); |
| 98 | env_del(e); |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | /* |
| 103 | * Built-in functions |
| 104 | */ |
| 105 | struct function { |
| 106 | const char *name; |
| 107 | unsigned int min_args; |
| 108 | unsigned int max_args; |
| 109 | char *(*func)(int argc, char *argv[]); |
| 110 | }; |
| 111 | |
| 112 | static char *do_error_if(int argc, char *argv[]) |
| 113 | { |
| 114 | if (!strcmp(argv[0], "y")) |
| 115 | pperror("%s", argv[1]); |
| 116 | |
| 117 | return xstrdup(""); |
| 118 | } |
| 119 | |
| 120 | static char *do_filename(int argc, char *argv[]) |
| 121 | { |
| 122 | return xstrdup(current_file->name); |
| 123 | } |
| 124 | |
| 125 | static char *do_info(int argc, char *argv[]) |
| 126 | { |
| 127 | printf("%s\n", argv[0]); |
| 128 | |
| 129 | return xstrdup(""); |
| 130 | } |
| 131 | |
| 132 | static char *do_lineno(int argc, char *argv[]) |
| 133 | { |
| 134 | char buf[16]; |
| 135 | |
| 136 | sprintf(buf, "%d", yylineno); |
| 137 | |
| 138 | return xstrdup(buf); |
| 139 | } |
| 140 | |
| 141 | static char *do_shell(int argc, char *argv[]) |
| 142 | { |
| 143 | FILE *p; |
Patrick Georgi | 7eb03cb | 2022-10-28 01:00:26 +0200 | [diff] [blame] | 144 | char buf[4096]; |
Patrick Georgi | 53ea1d4 | 2019-11-22 16:55:58 +0100 | [diff] [blame] | 145 | char *cmd; |
| 146 | size_t nread; |
| 147 | int i; |
| 148 | |
| 149 | cmd = argv[0]; |
| 150 | |
| 151 | p = popen(cmd, "r"); |
| 152 | if (!p) { |
| 153 | perror(cmd); |
| 154 | exit(1); |
| 155 | } |
| 156 | |
| 157 | nread = fread(buf, 1, sizeof(buf), p); |
| 158 | if (nread == sizeof(buf)) |
| 159 | nread--; |
| 160 | |
| 161 | /* remove trailing new lines */ |
| 162 | while (nread > 0 && buf[nread - 1] == '\n') |
| 163 | nread--; |
| 164 | |
| 165 | buf[nread] = 0; |
| 166 | |
| 167 | /* replace a new line with a space */ |
| 168 | for (i = 0; i < nread; i++) { |
| 169 | if (buf[i] == '\n') |
| 170 | buf[i] = ' '; |
| 171 | } |
| 172 | |
| 173 | if (pclose(p) == -1) { |
| 174 | perror(cmd); |
| 175 | exit(1); |
| 176 | } |
| 177 | |
| 178 | return xstrdup(buf); |
| 179 | } |
| 180 | |
| 181 | static char *do_warning_if(int argc, char *argv[]) |
| 182 | { |
| 183 | if (!strcmp(argv[0], "y")) |
| 184 | fprintf(stderr, "%s:%d: %s\n", |
| 185 | current_file->name, yylineno, argv[1]); |
| 186 | |
| 187 | return xstrdup(""); |
| 188 | } |
| 189 | |
| 190 | static const struct function function_table[] = { |
| 191 | /* Name MIN MAX Function */ |
| 192 | { "error-if", 2, 2, do_error_if }, |
| 193 | { "filename", 0, 0, do_filename }, |
| 194 | { "info", 1, 1, do_info }, |
| 195 | { "lineno", 0, 0, do_lineno }, |
| 196 | { "shell", 1, 1, do_shell }, |
| 197 | { "warning-if", 2, 2, do_warning_if }, |
| 198 | }; |
| 199 | |
| 200 | #define FUNCTION_MAX_ARGS 16 |
| 201 | |
| 202 | static char *function_expand(const char *name, int argc, char *argv[]) |
| 203 | { |
| 204 | const struct function *f; |
| 205 | int i; |
| 206 | |
| 207 | for (i = 0; i < ARRAY_SIZE(function_table); i++) { |
| 208 | f = &function_table[i]; |
| 209 | if (strcmp(f->name, name)) |
| 210 | continue; |
| 211 | |
| 212 | if (argc < f->min_args) |
| 213 | pperror("too few function arguments passed to '%s'", |
| 214 | name); |
| 215 | |
| 216 | if (argc > f->max_args) |
| 217 | pperror("too many function arguments passed to '%s'", |
| 218 | name); |
| 219 | |
| 220 | return f->func(argc, argv); |
| 221 | } |
| 222 | |
| 223 | return NULL; |
| 224 | } |
| 225 | |
| 226 | /* |
| 227 | * Variables (and user-defined functions) |
| 228 | */ |
| 229 | static LIST_HEAD(variable_list); |
| 230 | |
| 231 | struct variable { |
| 232 | char *name; |
| 233 | char *value; |
| 234 | enum variable_flavor flavor; |
| 235 | int exp_count; |
| 236 | struct list_head node; |
| 237 | }; |
| 238 | |
| 239 | static struct variable *variable_lookup(const char *name) |
| 240 | { |
| 241 | struct variable *v; |
| 242 | |
| 243 | list_for_each_entry(v, &variable_list, node) { |
| 244 | if (!strcmp(name, v->name)) |
| 245 | return v; |
| 246 | } |
| 247 | |
| 248 | return NULL; |
| 249 | } |
| 250 | |
| 251 | static char *variable_expand(const char *name, int argc, char *argv[]) |
| 252 | { |
| 253 | struct variable *v; |
| 254 | char *res; |
| 255 | |
| 256 | v = variable_lookup(name); |
| 257 | if (!v) |
| 258 | return NULL; |
| 259 | |
| 260 | if (argc == 0 && v->exp_count) |
| 261 | pperror("Recursive variable '%s' references itself (eventually)", |
| 262 | name); |
| 263 | |
| 264 | if (v->exp_count > 1000) |
| 265 | pperror("Too deep recursive expansion"); |
| 266 | |
| 267 | v->exp_count++; |
| 268 | |
| 269 | if (v->flavor == VAR_RECURSIVE) |
| 270 | res = expand_string_with_args(v->value, argc, argv); |
| 271 | else |
| 272 | res = xstrdup(v->value); |
| 273 | |
| 274 | v->exp_count--; |
| 275 | |
| 276 | return res; |
| 277 | } |
| 278 | |
| 279 | void variable_add(const char *name, const char *value, |
| 280 | enum variable_flavor flavor) |
| 281 | { |
| 282 | struct variable *v; |
| 283 | char *new_value; |
| 284 | bool append = false; |
| 285 | |
| 286 | v = variable_lookup(name); |
| 287 | if (v) { |
| 288 | /* For defined variables, += inherits the existing flavor */ |
| 289 | if (flavor == VAR_APPEND) { |
| 290 | flavor = v->flavor; |
| 291 | append = true; |
| 292 | } else { |
| 293 | free(v->value); |
| 294 | } |
| 295 | } else { |
| 296 | /* For undefined variables, += assumes the recursive flavor */ |
| 297 | if (flavor == VAR_APPEND) |
| 298 | flavor = VAR_RECURSIVE; |
| 299 | |
| 300 | v = xmalloc(sizeof(*v)); |
| 301 | v->name = xstrdup(name); |
| 302 | v->exp_count = 0; |
| 303 | list_add_tail(&v->node, &variable_list); |
| 304 | } |
| 305 | |
| 306 | v->flavor = flavor; |
| 307 | |
| 308 | if (flavor == VAR_SIMPLE) |
| 309 | new_value = expand_string(value); |
| 310 | else |
| 311 | new_value = xstrdup(value); |
| 312 | |
| 313 | if (append) { |
| 314 | v->value = xrealloc(v->value, |
| 315 | strlen(v->value) + strlen(new_value) + 2); |
| 316 | strcat(v->value, " "); |
| 317 | strcat(v->value, new_value); |
| 318 | free(new_value); |
| 319 | } else { |
| 320 | v->value = new_value; |
| 321 | } |
| 322 | } |
| 323 | |
| 324 | static void variable_del(struct variable *v) |
| 325 | { |
| 326 | list_del(&v->node); |
| 327 | free(v->name); |
| 328 | free(v->value); |
| 329 | free(v); |
| 330 | } |
| 331 | |
| 332 | void variable_all_del(void) |
| 333 | { |
| 334 | struct variable *v, *tmp; |
| 335 | |
| 336 | list_for_each_entry_safe(v, tmp, &variable_list, node) |
| 337 | variable_del(v); |
| 338 | } |
| 339 | |
| 340 | /* |
| 341 | * Evaluate a clause with arguments. argc/argv are arguments from the upper |
| 342 | * function call. |
| 343 | * |
| 344 | * Returned string must be freed when done |
| 345 | */ |
| 346 | static char *eval_clause(const char *str, size_t len, int argc, char *argv[]) |
| 347 | { |
| 348 | char *tmp, *name, *res, *endptr, *prev, *p; |
| 349 | int new_argc = 0; |
| 350 | char *new_argv[FUNCTION_MAX_ARGS]; |
| 351 | int nest = 0; |
| 352 | int i; |
| 353 | unsigned long n; |
| 354 | |
| 355 | tmp = xstrndup(str, len); |
| 356 | |
| 357 | /* |
| 358 | * If variable name is '1', '2', etc. It is generally an argument |
| 359 | * from a user-function call (i.e. local-scope variable). If not |
| 360 | * available, then look-up global-scope variables. |
| 361 | */ |
| 362 | n = strtoul(tmp, &endptr, 10); |
| 363 | if (!*endptr && n > 0 && n <= argc) { |
| 364 | res = xstrdup(argv[n - 1]); |
| 365 | goto free_tmp; |
| 366 | } |
| 367 | |
| 368 | prev = p = tmp; |
| 369 | |
| 370 | /* |
| 371 | * Split into tokens |
| 372 | * The function name and arguments are separated by a comma. |
| 373 | * For example, if the function call is like this: |
| 374 | * $(foo,$(x),$(y)) |
| 375 | * |
| 376 | * The input string for this helper should be: |
| 377 | * foo,$(x),$(y) |
| 378 | * |
| 379 | * and split into: |
| 380 | * new_argv[0] = 'foo' |
| 381 | * new_argv[1] = '$(x)' |
| 382 | * new_argv[2] = '$(y)' |
| 383 | */ |
| 384 | while (*p) { |
| 385 | if (nest == 0 && *p == ',') { |
| 386 | *p = 0; |
| 387 | if (new_argc >= FUNCTION_MAX_ARGS) |
| 388 | pperror("too many function arguments"); |
| 389 | new_argv[new_argc++] = prev; |
| 390 | prev = p + 1; |
| 391 | } else if (*p == '(') { |
| 392 | nest++; |
| 393 | } else if (*p == ')') { |
| 394 | nest--; |
| 395 | } |
| 396 | |
| 397 | p++; |
| 398 | } |
Patrick Georgi | 0eab62b | 2023-11-20 19:49:29 +0100 | [diff] [blame] | 399 | |
| 400 | if (new_argc >= FUNCTION_MAX_ARGS) |
| 401 | pperror("too many function arguments"); |
Patrick Georgi | 53ea1d4 | 2019-11-22 16:55:58 +0100 | [diff] [blame] | 402 | new_argv[new_argc++] = prev; |
| 403 | |
| 404 | /* |
| 405 | * Shift arguments |
| 406 | * new_argv[0] represents a function name or a variable name. Put it |
| 407 | * into 'name', then shift the rest of the arguments. This simplifies |
| 408 | * 'const' handling. |
| 409 | */ |
| 410 | name = expand_string_with_args(new_argv[0], argc, argv); |
| 411 | new_argc--; |
| 412 | for (i = 0; i < new_argc; i++) |
| 413 | new_argv[i] = expand_string_with_args(new_argv[i + 1], |
| 414 | argc, argv); |
| 415 | |
| 416 | /* Search for variables */ |
| 417 | res = variable_expand(name, new_argc, new_argv); |
| 418 | if (res) |
| 419 | goto free; |
| 420 | |
| 421 | /* Look for built-in functions */ |
| 422 | res = function_expand(name, new_argc, new_argv); |
| 423 | if (res) |
| 424 | goto free; |
| 425 | |
| 426 | /* Last, try environment variable */ |
| 427 | if (new_argc == 0) { |
| 428 | res = env_expand(name); |
| 429 | if (res) |
| 430 | goto free; |
| 431 | } |
| 432 | |
| 433 | res = xstrdup(""); |
| 434 | free: |
| 435 | for (i = 0; i < new_argc; i++) |
| 436 | free(new_argv[i]); |
| 437 | free(name); |
| 438 | free_tmp: |
| 439 | free(tmp); |
| 440 | |
| 441 | return res; |
| 442 | } |
| 443 | |
| 444 | /* |
| 445 | * Expand a string that follows '$' |
| 446 | * |
| 447 | * For example, if the input string is |
| 448 | * ($(FOO)$($(BAR)))$(BAZ) |
| 449 | * this helper evaluates |
| 450 | * $($(FOO)$($(BAR))) |
| 451 | * and returns a new string containing the expansion (note that the string is |
| 452 | * recursively expanded), also advancing 'str' to point to the next character |
| 453 | * after the corresponding closing parenthesis, in this case, *str will be |
| 454 | * $(BAR) |
| 455 | */ |
| 456 | static char *expand_dollar_with_args(const char **str, int argc, char *argv[]) |
| 457 | { |
| 458 | const char *p = *str; |
| 459 | const char *q; |
| 460 | int nest = 0; |
| 461 | |
| 462 | /* |
| 463 | * In Kconfig, variable/function references always start with "$(". |
| 464 | * Neither single-letter variables as in $A nor curly braces as in ${CC} |
| 465 | * are supported. '$' not followed by '(' loses its special meaning. |
| 466 | */ |
| 467 | if (*p != '(') { |
| 468 | *str = p; |
| 469 | return xstrdup("$"); |
| 470 | } |
| 471 | |
| 472 | p++; |
| 473 | q = p; |
| 474 | while (*q) { |
| 475 | if (*q == '(') { |
| 476 | nest++; |
| 477 | } else if (*q == ')') { |
| 478 | if (nest-- == 0) |
| 479 | break; |
| 480 | } |
| 481 | q++; |
| 482 | } |
| 483 | |
| 484 | if (!*q) |
| 485 | pperror("unterminated reference to '%s': missing ')'", p); |
| 486 | |
| 487 | /* Advance 'str' to after the expanded initial portion of the string */ |
| 488 | *str = q + 1; |
| 489 | |
| 490 | return eval_clause(p, q - p, argc, argv); |
| 491 | } |
| 492 | |
| 493 | char *expand_dollar(const char **str) |
| 494 | { |
| 495 | return expand_dollar_with_args(str, 0, NULL); |
| 496 | } |
| 497 | |
| 498 | static char *__expand_string(const char **str, bool (*is_end)(char c), |
| 499 | int argc, char *argv[]) |
| 500 | { |
| 501 | const char *in, *p; |
| 502 | char *expansion, *out; |
| 503 | size_t in_len, out_len; |
| 504 | |
| 505 | out = xmalloc(1); |
| 506 | *out = 0; |
| 507 | out_len = 1; |
| 508 | |
| 509 | p = in = *str; |
| 510 | |
| 511 | while (1) { |
| 512 | if (*p == '$') { |
| 513 | in_len = p - in; |
| 514 | p++; |
| 515 | expansion = expand_dollar_with_args(&p, argc, argv); |
| 516 | out_len += in_len + strlen(expansion); |
| 517 | out = xrealloc(out, out_len); |
| 518 | strncat(out, in, in_len); |
| 519 | strcat(out, expansion); |
| 520 | free(expansion); |
| 521 | in = p; |
| 522 | continue; |
| 523 | } |
| 524 | |
| 525 | if (is_end(*p)) |
| 526 | break; |
| 527 | |
| 528 | p++; |
| 529 | } |
| 530 | |
| 531 | in_len = p - in; |
| 532 | out_len += in_len; |
| 533 | out = xrealloc(out, out_len); |
| 534 | strncat(out, in, in_len); |
| 535 | |
| 536 | /* Advance 'str' to the end character */ |
| 537 | *str = p; |
| 538 | |
| 539 | return out; |
| 540 | } |
| 541 | |
| 542 | static bool is_end_of_str(char c) |
| 543 | { |
| 544 | return !c; |
| 545 | } |
| 546 | |
| 547 | /* |
| 548 | * Expand variables and functions in the given string. Undefined variables |
| 549 | * expand to an empty string. |
| 550 | * The returned string must be freed when done. |
| 551 | */ |
| 552 | static char *expand_string_with_args(const char *in, int argc, char *argv[]) |
| 553 | { |
| 554 | return __expand_string(&in, is_end_of_str, argc, argv); |
| 555 | } |
| 556 | |
| 557 | static char *expand_string(const char *in) |
| 558 | { |
| 559 | return expand_string_with_args(in, 0, NULL); |
| 560 | } |
| 561 | |
| 562 | static bool is_end_of_token(char c) |
| 563 | { |
| 564 | return !(isalnum(c) || c == '_' || c == '-'); |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * Expand variables in a token. The parsing stops when a token separater |
| 569 | * (in most cases, it is a whitespace) is encountered. 'str' is updated to |
| 570 | * point to the next character. |
| 571 | * |
| 572 | * The returned string must be freed when done. |
| 573 | */ |
| 574 | char *expand_one_token(const char **str) |
| 575 | { |
| 576 | return __expand_string(str, is_end_of_token, 0, NULL); |
| 577 | } |