1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * config.c 4 * 5 * Helper functions for parsing config items. 6 * Originally copied from GIT source. 7 * 8 * Copyright (C) Linus Torvalds, 2005 9 * Copyright (C) Johannes Schindelin, 2005 10 * 11 */ 12 #include <errno.h> 13 #include <sys/param.h> 14 #include "cache.h" 15 #include "callchain.h" 16 #include <subcmd/exec-cmd.h> 17 #include "util/event.h" /* proc_map_timeout */ 18 #include "util/hist.h" /* perf_hist_config */ 19 #include "util/llvm-utils.h" /* perf_llvm_config */ 20 #include "build-id.h" 21 #include "debug.h" 22 #include "config.h" 23 #include "debug.h" 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <stdlib.h> 27 #include <unistd.h> 28 #include <linux/string.h> 29 #include <linux/zalloc.h> 30 #include <linux/ctype.h> 31 32 #define MAXNAME (256) 33 34 #define DEBUG_CACHE_DIR ".debug" 35 36 37 char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */ 38 39 static FILE *config_file; 40 static const char *config_file_name; 41 static int config_linenr; 42 static int config_file_eof; 43 static struct perf_config_set *config_set; 44 45 const char *config_exclusive_filename; 46 47 static int get_next_char(void) 48 { 49 int c; 50 FILE *f; 51 52 c = '\n'; 53 if ((f = config_file) != NULL) { 54 c = fgetc(f); 55 if (c == '\r') { 56 /* DOS like systems */ 57 c = fgetc(f); 58 if (c != '\n') { 59 ungetc(c, f); 60 c = '\r'; 61 } 62 } 63 if (c == '\n') 64 config_linenr++; 65 if (c == EOF) { 66 config_file_eof = 1; 67 c = '\n'; 68 } 69 } 70 return c; 71 } 72 73 static char *parse_value(void) 74 { 75 static char value[1024]; 76 int quote = 0, comment = 0, space = 0; 77 size_t len = 0; 78 79 for (;;) { 80 int c = get_next_char(); 81 82 if (len >= sizeof(value) - 1) 83 return NULL; 84 if (c == '\n') { 85 if (quote) 86 return NULL; 87 value[len] = 0; 88 return value; 89 } 90 if (comment) 91 continue; 92 if (isspace(c) && !quote) { 93 space = 1; 94 continue; 95 } 96 if (!quote) { 97 if (c == ';' || c == '#') { 98 comment = 1; 99 continue; 100 } 101 } 102 if (space) { 103 if (len) 104 value[len++] = ' '; 105 space = 0; 106 } 107 if (c == '\\') { 108 c = get_next_char(); 109 switch (c) { 110 case '\n': 111 continue; 112 case 't': 113 c = '\t'; 114 break; 115 case 'b': 116 c = '\b'; 117 break; 118 case 'n': 119 c = '\n'; 120 break; 121 /* Some characters escape as themselves */ 122 case '\\': case '"': 123 break; 124 /* Reject unknown escape sequences */ 125 default: 126 return NULL; 127 } 128 value[len++] = c; 129 continue; 130 } 131 if (c == '"') { 132 quote = 1-quote; 133 continue; 134 } 135 value[len++] = c; 136 } 137 } 138 139 static inline int iskeychar(int c) 140 { 141 return isalnum(c) || c == '-' || c == '_'; 142 } 143 144 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len) 145 { 146 int c; 147 char *value; 148 149 /* Get the full name */ 150 for (;;) { 151 c = get_next_char(); 152 if (config_file_eof) 153 break; 154 if (!iskeychar(c)) 155 break; 156 name[len++] = c; 157 if (len >= MAXNAME) 158 return -1; 159 } 160 name[len] = 0; 161 while (c == ' ' || c == '\t') 162 c = get_next_char(); 163 164 value = NULL; 165 if (c != '\n') { 166 if (c != '=') 167 return -1; 168 value = parse_value(); 169 if (!value) 170 return -1; 171 } 172 return fn(name, value, data); 173 } 174 175 static int get_extended_base_var(char *name, int baselen, int c) 176 { 177 do { 178 if (c == '\n') 179 return -1; 180 c = get_next_char(); 181 } while (isspace(c)); 182 183 /* We require the format to be '[base "extension"]' */ 184 if (c != '"') 185 return -1; 186 name[baselen++] = '.'; 187 188 for (;;) { 189 int ch = get_next_char(); 190 191 if (ch == '\n') 192 return -1; 193 if (ch == '"') 194 break; 195 if (ch == '\\') { 196 ch = get_next_char(); 197 if (ch == '\n') 198 return -1; 199 } 200 name[baselen++] = ch; 201 if (baselen > MAXNAME / 2) 202 return -1; 203 } 204 205 /* Final ']' */ 206 if (get_next_char() != ']') 207 return -1; 208 return baselen; 209 } 210 211 static int get_base_var(char *name) 212 { 213 int baselen = 0; 214 215 for (;;) { 216 int c = get_next_char(); 217 if (config_file_eof) 218 return -1; 219 if (c == ']') 220 return baselen; 221 if (isspace(c)) 222 return get_extended_base_var(name, baselen, c); 223 if (!iskeychar(c) && c != '.') 224 return -1; 225 if (baselen > MAXNAME / 2) 226 return -1; 227 name[baselen++] = tolower(c); 228 } 229 } 230 231 static int perf_parse_file(config_fn_t fn, void *data) 232 { 233 int comment = 0; 234 int baselen = 0; 235 static char var[MAXNAME]; 236 237 /* U+FEFF Byte Order Mark in UTF8 */ 238 static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf"; 239 const unsigned char *bomptr = utf8_bom; 240 241 for (;;) { 242 int line, c = get_next_char(); 243 244 if (bomptr && *bomptr) { 245 /* We are at the file beginning; skip UTF8-encoded BOM 246 * if present. Sane editors won't put this in on their 247 * own, but e.g. Windows Notepad will do it happily. */ 248 if ((unsigned char) c == *bomptr) { 249 bomptr++; 250 continue; 251 } else { 252 /* Do not tolerate partial BOM. */ 253 if (bomptr != utf8_bom) 254 break; 255 /* No BOM at file beginning. Cool. */ 256 bomptr = NULL; 257 } 258 } 259 if (c == '\n') { 260 if (config_file_eof) 261 return 0; 262 comment = 0; 263 continue; 264 } 265 if (comment || isspace(c)) 266 continue; 267 if (c == '#' || c == ';') { 268 comment = 1; 269 continue; 270 } 271 if (c == '[') { 272 baselen = get_base_var(var); 273 if (baselen <= 0) 274 break; 275 var[baselen++] = '.'; 276 var[baselen] = 0; 277 continue; 278 } 279 if (!isalpha(c)) 280 break; 281 var[baselen] = tolower(c); 282 283 /* 284 * The get_value function might or might not reach the '\n', 285 * so saving the current line number for error reporting. 286 */ 287 line = config_linenr; 288 if (get_value(fn, data, var, baselen+1) < 0) { 289 config_linenr = line; 290 break; 291 } 292 } 293 pr_err("bad config file line %d in %s\n", config_linenr, config_file_name); 294 return -1; 295 } 296 297 static int parse_unit_factor(const char *end, unsigned long *val) 298 { 299 if (!*end) 300 return 1; 301 else if (!strcasecmp(end, "k")) { 302 *val *= 1024; 303 return 1; 304 } 305 else if (!strcasecmp(end, "m")) { 306 *val *= 1024 * 1024; 307 return 1; 308 } 309 else if (!strcasecmp(end, "g")) { 310 *val *= 1024 * 1024 * 1024; 311 return 1; 312 } 313 return 0; 314 } 315 316 static int perf_parse_llong(const char *value, long long *ret) 317 { 318 if (value && *value) { 319 char *end; 320 long long val = strtoll(value, &end, 0); 321 unsigned long factor = 1; 322 323 if (!parse_unit_factor(end, &factor)) 324 return 0; 325 *ret = val * factor; 326 return 1; 327 } 328 return 0; 329 } 330 331 static int perf_parse_long(const char *value, long *ret) 332 { 333 if (value && *value) { 334 char *end; 335 long val = strtol(value, &end, 0); 336 unsigned long factor = 1; 337 if (!parse_unit_factor(end, &factor)) 338 return 0; 339 *ret = val * factor; 340 return 1; 341 } 342 return 0; 343 } 344 345 static void bad_config(const char *name) 346 { 347 if (config_file_name) 348 pr_warning("bad config value for '%s' in %s, ignoring...\n", name, config_file_name); 349 else 350 pr_warning("bad config value for '%s', ignoring...\n", name); 351 } 352 353 int perf_config_u64(u64 *dest, const char *name, const char *value) 354 { 355 long long ret = 0; 356 357 if (!perf_parse_llong(value, &ret)) { 358 bad_config(name); 359 return -1; 360 } 361 362 *dest = ret; 363 return 0; 364 } 365 366 int perf_config_int(int *dest, const char *name, const char *value) 367 { 368 long ret = 0; 369 if (!perf_parse_long(value, &ret)) { 370 bad_config(name); 371 return -1; 372 } 373 *dest = ret; 374 return 0; 375 } 376 377 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool) 378 { 379 int ret; 380 381 *is_bool = 1; 382 if (!value) 383 return 1; 384 if (!*value) 385 return 0; 386 if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on")) 387 return 1; 388 if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off")) 389 return 0; 390 *is_bool = 0; 391 return perf_config_int(&ret, name, value) < 0 ? -1 : ret; 392 } 393 394 int perf_config_bool(const char *name, const char *value) 395 { 396 int discard; 397 return !!perf_config_bool_or_int(name, value, &discard); 398 } 399 400 static const char *perf_config_dirname(const char *name, const char *value) 401 { 402 if (!name) 403 return NULL; 404 return value; 405 } 406 407 static int perf_buildid_config(const char *var, const char *value) 408 { 409 /* same dir for all commands */ 410 if (!strcmp(var, "buildid.dir")) { 411 const char *dir = perf_config_dirname(var, value); 412 413 if (!dir) { 414 pr_err("Invalid buildid directory!\n"); 415 return -1; 416 } 417 strncpy(buildid_dir, dir, MAXPATHLEN-1); 418 buildid_dir[MAXPATHLEN-1] = '\0'; 419 } 420 421 return 0; 422 } 423 424 static int perf_default_core_config(const char *var __maybe_unused, 425 const char *value __maybe_unused) 426 { 427 if (!strcmp(var, "core.proc-map-timeout")) 428 proc_map_timeout = strtoul(value, NULL, 10); 429 430 /* Add other config variables here. */ 431 return 0; 432 } 433 434 static int perf_ui_config(const char *var, const char *value) 435 { 436 /* Add other config variables here. */ 437 if (!strcmp(var, "ui.show-headers")) 438 symbol_conf.show_hist_headers = perf_config_bool(var, value); 439 440 return 0; 441 } 442 443 int perf_default_config(const char *var, const char *value, 444 void *dummy __maybe_unused) 445 { 446 if (strstarts(var, "core.")) 447 return perf_default_core_config(var, value); 448 449 if (strstarts(var, "hist.")) 450 return perf_hist_config(var, value); 451 452 if (strstarts(var, "ui.")) 453 return perf_ui_config(var, value); 454 455 if (strstarts(var, "call-graph.")) 456 return perf_callchain_config(var, value); 457 458 if (strstarts(var, "llvm.")) 459 return perf_llvm_config(var, value); 460 461 if (strstarts(var, "buildid.")) 462 return perf_buildid_config(var, value); 463 464 /* Add other config variables here. */ 465 return 0; 466 } 467 468 static int perf_config_from_file(config_fn_t fn, const char *filename, void *data) 469 { 470 int ret; 471 FILE *f = fopen(filename, "r"); 472 473 ret = -1; 474 if (f) { 475 config_file = f; 476 config_file_name = filename; 477 config_linenr = 1; 478 config_file_eof = 0; 479 ret = perf_parse_file(fn, data); 480 fclose(f); 481 config_file_name = NULL; 482 } 483 return ret; 484 } 485 486 const char *perf_etc_perfconfig(void) 487 { 488 static const char *system_wide; 489 if (!system_wide) 490 system_wide = system_path(ETC_PERFCONFIG); 491 return system_wide; 492 } 493 494 static int perf_env_bool(const char *k, int def) 495 { 496 const char *v = getenv(k); 497 return v ? perf_config_bool(k, v) : def; 498 } 499 500 static int perf_config_system(void) 501 { 502 return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0); 503 } 504 505 static int perf_config_global(void) 506 { 507 return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0); 508 } 509 510 static struct perf_config_section *find_section(struct list_head *sections, 511 const char *section_name) 512 { 513 struct perf_config_section *section; 514 515 list_for_each_entry(section, sections, node) 516 if (!strcmp(section->name, section_name)) 517 return section; 518 519 return NULL; 520 } 521 522 static struct perf_config_item *find_config_item(const char *name, 523 struct perf_config_section *section) 524 { 525 struct perf_config_item *item; 526 527 list_for_each_entry(item, §ion->items, node) 528 if (!strcmp(item->name, name)) 529 return item; 530 531 return NULL; 532 } 533 534 static struct perf_config_section *add_section(struct list_head *sections, 535 const char *section_name) 536 { 537 struct perf_config_section *section = zalloc(sizeof(*section)); 538 539 if (!section) 540 return NULL; 541 542 INIT_LIST_HEAD(§ion->items); 543 section->name = strdup(section_name); 544 if (!section->name) { 545 pr_debug("%s: strdup failed\n", __func__); 546 free(section); 547 return NULL; 548 } 549 550 list_add_tail(§ion->node, sections); 551 return section; 552 } 553 554 static struct perf_config_item *add_config_item(struct perf_config_section *section, 555 const char *name) 556 { 557 struct perf_config_item *item = zalloc(sizeof(*item)); 558 559 if (!item) 560 return NULL; 561 562 item->name = strdup(name); 563 if (!item->name) { 564 pr_debug("%s: strdup failed\n", __func__); 565 free(item); 566 return NULL; 567 } 568 569 list_add_tail(&item->node, §ion->items); 570 return item; 571 } 572 573 static int set_value(struct perf_config_item *item, const char *value) 574 { 575 char *val = strdup(value); 576 577 if (!val) 578 return -1; 579 580 zfree(&item->value); 581 item->value = val; 582 return 0; 583 } 584 585 static int collect_config(const char *var, const char *value, 586 void *perf_config_set) 587 { 588 int ret = -1; 589 char *ptr, *key; 590 char *section_name, *name; 591 struct perf_config_section *section = NULL; 592 struct perf_config_item *item = NULL; 593 struct perf_config_set *set = perf_config_set; 594 struct list_head *sections; 595 596 if (set == NULL) 597 return -1; 598 599 sections = &set->sections; 600 key = ptr = strdup(var); 601 if (!key) { 602 pr_debug("%s: strdup failed\n", __func__); 603 return -1; 604 } 605 606 section_name = strsep(&ptr, "."); 607 name = ptr; 608 if (name == NULL || value == NULL) 609 goto out_free; 610 611 section = find_section(sections, section_name); 612 if (!section) { 613 section = add_section(sections, section_name); 614 if (!section) 615 goto out_free; 616 } 617 618 item = find_config_item(name, section); 619 if (!item) { 620 item = add_config_item(section, name); 621 if (!item) 622 goto out_free; 623 } 624 625 /* perf_config_set can contain both user and system config items. 626 * So we should know where each value is from. 627 * The classification would be needed when a particular config file 628 * is overwrited by setting feature i.e. set_config(). 629 */ 630 if (strcmp(config_file_name, perf_etc_perfconfig()) == 0) { 631 section->from_system_config = true; 632 item->from_system_config = true; 633 } else { 634 section->from_system_config = false; 635 item->from_system_config = false; 636 } 637 638 ret = set_value(item, value); 639 640 out_free: 641 free(key); 642 return ret; 643 } 644 645 int perf_config_set__collect(struct perf_config_set *set, const char *file_name, 646 const char *var, const char *value) 647 { 648 config_file_name = file_name; 649 return collect_config(var, value, set); 650 } 651 652 static int perf_config_set__init(struct perf_config_set *set) 653 { 654 int ret = -1; 655 const char *home = NULL; 656 char *user_config; 657 struct stat st; 658 659 /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */ 660 if (config_exclusive_filename) 661 return perf_config_from_file(collect_config, config_exclusive_filename, set); 662 if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) { 663 if (perf_config_from_file(collect_config, perf_etc_perfconfig(), set) < 0) 664 goto out; 665 } 666 667 home = getenv("HOME"); 668 669 /* 670 * Skip reading user config if: 671 * - there is no place to read it from (HOME) 672 * - we are asked not to (PERF_CONFIG_NOGLOBAL=1) 673 */ 674 if (!home || !*home || !perf_config_global()) 675 return 0; 676 677 user_config = strdup(mkpath("%s/.perfconfig", home)); 678 if (user_config == NULL) { 679 pr_warning("Not enough memory to process %s/.perfconfig, ignoring it.", home); 680 goto out; 681 } 682 683 if (stat(user_config, &st) < 0) { 684 if (errno == ENOENT) 685 ret = 0; 686 goto out_free; 687 } 688 689 ret = 0; 690 691 if (st.st_uid && (st.st_uid != geteuid())) { 692 pr_warning("File %s not owned by current user or root, ignoring it.", user_config); 693 goto out_free; 694 } 695 696 if (st.st_size) 697 ret = perf_config_from_file(collect_config, user_config, set); 698 699 out_free: 700 free(user_config); 701 out: 702 return ret; 703 } 704 705 struct perf_config_set *perf_config_set__new(void) 706 { 707 struct perf_config_set *set = zalloc(sizeof(*set)); 708 709 if (set) { 710 INIT_LIST_HEAD(&set->sections); 711 perf_config_set__init(set); 712 } 713 714 return set; 715 } 716 717 static int perf_config__init(void) 718 { 719 if (config_set == NULL) 720 config_set = perf_config_set__new(); 721 722 return config_set == NULL; 723 } 724 725 int perf_config(config_fn_t fn, void *data) 726 { 727 int ret = 0; 728 char key[BUFSIZ]; 729 struct perf_config_section *section; 730 struct perf_config_item *item; 731 732 if (config_set == NULL && perf_config__init()) 733 return -1; 734 735 perf_config_set__for_each_entry(config_set, section, item) { 736 char *value = item->value; 737 738 if (value) { 739 scnprintf(key, sizeof(key), "%s.%s", 740 section->name, item->name); 741 ret = fn(key, value, data); 742 if (ret < 0) { 743 pr_err("Error: wrong config key-value pair %s=%s\n", 744 key, value); 745 /* 746 * Can't be just a 'break', as perf_config_set__for_each_entry() 747 * expands to two nested for() loops. 748 */ 749 goto out; 750 } 751 } 752 } 753 out: 754 return ret; 755 } 756 757 void perf_config__exit(void) 758 { 759 perf_config_set__delete(config_set); 760 config_set = NULL; 761 } 762 763 void perf_config__refresh(void) 764 { 765 perf_config__exit(); 766 perf_config__init(); 767 } 768 769 static void perf_config_item__delete(struct perf_config_item *item) 770 { 771 zfree(&item->name); 772 zfree(&item->value); 773 free(item); 774 } 775 776 static void perf_config_section__purge(struct perf_config_section *section) 777 { 778 struct perf_config_item *item, *tmp; 779 780 list_for_each_entry_safe(item, tmp, §ion->items, node) { 781 list_del_init(&item->node); 782 perf_config_item__delete(item); 783 } 784 } 785 786 static void perf_config_section__delete(struct perf_config_section *section) 787 { 788 perf_config_section__purge(section); 789 zfree(§ion->name); 790 free(section); 791 } 792 793 static void perf_config_set__purge(struct perf_config_set *set) 794 { 795 struct perf_config_section *section, *tmp; 796 797 list_for_each_entry_safe(section, tmp, &set->sections, node) { 798 list_del_init(§ion->node); 799 perf_config_section__delete(section); 800 } 801 } 802 803 void perf_config_set__delete(struct perf_config_set *set) 804 { 805 if (set == NULL) 806 return; 807 808 perf_config_set__purge(set); 809 free(set); 810 } 811 812 /* 813 * Call this to report error for your variable that should not 814 * get a boolean value (i.e. "[my] var" means "true"). 815 */ 816 int config_error_nonbool(const char *var) 817 { 818 pr_err("Missing value for '%s'", var); 819 return -1; 820 } 821 822 void set_buildid_dir(const char *dir) 823 { 824 if (dir) 825 scnprintf(buildid_dir, MAXPATHLEN, "%s", dir); 826 827 /* default to $HOME/.debug */ 828 if (buildid_dir[0] == '\0') { 829 char *home = getenv("HOME"); 830 831 if (home) { 832 snprintf(buildid_dir, MAXPATHLEN, "%s/%s", 833 home, DEBUG_CACHE_DIR); 834 } else { 835 strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1); 836 } 837 buildid_dir[MAXPATHLEN-1] = '\0'; 838 } 839 /* for communicating with external commands */ 840 setenv("PERF_BUILDID_DIR", buildid_dir, 1); 841 } 842