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 "util/stat.h" /* perf_stat__set_big_num */ 21 #include "build-id.h" 22 #include "debug.h" 23 #include "config.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 int perf_config_u8(u8 *dest, const char *name, const char *value) 378 { 379 long ret = 0; 380 381 if (!perf_parse_long(value, &ret)) { 382 bad_config(name); 383 return -1; 384 } 385 *dest = ret; 386 return 0; 387 } 388 389 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool) 390 { 391 int ret; 392 393 *is_bool = 1; 394 if (!value) 395 return 1; 396 if (!*value) 397 return 0; 398 if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on")) 399 return 1; 400 if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off")) 401 return 0; 402 *is_bool = 0; 403 return perf_config_int(&ret, name, value) < 0 ? -1 : ret; 404 } 405 406 int perf_config_bool(const char *name, const char *value) 407 { 408 int discard; 409 return !!perf_config_bool_or_int(name, value, &discard); 410 } 411 412 static const char *perf_config_dirname(const char *name, const char *value) 413 { 414 if (!name) 415 return NULL; 416 return value; 417 } 418 419 static int perf_buildid_config(const char *var, const char *value) 420 { 421 /* same dir for all commands */ 422 if (!strcmp(var, "buildid.dir")) { 423 const char *dir = perf_config_dirname(var, value); 424 425 if (!dir) { 426 pr_err("Invalid buildid directory!\n"); 427 return -1; 428 } 429 strncpy(buildid_dir, dir, MAXPATHLEN-1); 430 buildid_dir[MAXPATHLEN-1] = '\0'; 431 } 432 433 return 0; 434 } 435 436 static int perf_default_core_config(const char *var __maybe_unused, 437 const char *value __maybe_unused) 438 { 439 if (!strcmp(var, "core.proc-map-timeout")) 440 proc_map_timeout = strtoul(value, NULL, 10); 441 442 /* Add other config variables here. */ 443 return 0; 444 } 445 446 static int perf_ui_config(const char *var, const char *value) 447 { 448 /* Add other config variables here. */ 449 if (!strcmp(var, "ui.show-headers")) 450 symbol_conf.show_hist_headers = perf_config_bool(var, value); 451 452 return 0; 453 } 454 455 static int perf_stat_config(const char *var, const char *value) 456 { 457 if (!strcmp(var, "stat.big-num")) 458 perf_stat__set_big_num(perf_config_bool(var, value)); 459 460 /* Add other config variables here. */ 461 return 0; 462 } 463 464 int perf_default_config(const char *var, const char *value, 465 void *dummy __maybe_unused) 466 { 467 if (strstarts(var, "core.")) 468 return perf_default_core_config(var, value); 469 470 if (strstarts(var, "hist.")) 471 return perf_hist_config(var, value); 472 473 if (strstarts(var, "ui.")) 474 return perf_ui_config(var, value); 475 476 if (strstarts(var, "call-graph.")) 477 return perf_callchain_config(var, value); 478 479 if (strstarts(var, "llvm.")) 480 return perf_llvm_config(var, value); 481 482 if (strstarts(var, "buildid.")) 483 return perf_buildid_config(var, value); 484 485 if (strstarts(var, "stat.")) 486 return perf_stat_config(var, value); 487 488 /* Add other config variables here. */ 489 return 0; 490 } 491 492 int perf_config_from_file(config_fn_t fn, const char *filename, void *data) 493 { 494 int ret; 495 FILE *f = fopen(filename, "r"); 496 497 ret = -1; 498 if (f) { 499 config_file = f; 500 config_file_name = filename; 501 config_linenr = 1; 502 config_file_eof = 0; 503 ret = perf_parse_file(fn, data); 504 fclose(f); 505 config_file_name = NULL; 506 } 507 return ret; 508 } 509 510 const char *perf_etc_perfconfig(void) 511 { 512 static const char *system_wide; 513 if (!system_wide) 514 system_wide = system_path(ETC_PERFCONFIG); 515 return system_wide; 516 } 517 518 static int perf_env_bool(const char *k, int def) 519 { 520 const char *v = getenv(k); 521 return v ? perf_config_bool(k, v) : def; 522 } 523 524 static int perf_config_system(void) 525 { 526 return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0); 527 } 528 529 static int perf_config_global(void) 530 { 531 return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0); 532 } 533 534 static struct perf_config_section *find_section(struct list_head *sections, 535 const char *section_name) 536 { 537 struct perf_config_section *section; 538 539 list_for_each_entry(section, sections, node) 540 if (!strcmp(section->name, section_name)) 541 return section; 542 543 return NULL; 544 } 545 546 static struct perf_config_item *find_config_item(const char *name, 547 struct perf_config_section *section) 548 { 549 struct perf_config_item *item; 550 551 list_for_each_entry(item, §ion->items, node) 552 if (!strcmp(item->name, name)) 553 return item; 554 555 return NULL; 556 } 557 558 static struct perf_config_section *add_section(struct list_head *sections, 559 const char *section_name) 560 { 561 struct perf_config_section *section = zalloc(sizeof(*section)); 562 563 if (!section) 564 return NULL; 565 566 INIT_LIST_HEAD(§ion->items); 567 section->name = strdup(section_name); 568 if (!section->name) { 569 pr_debug("%s: strdup failed\n", __func__); 570 free(section); 571 return NULL; 572 } 573 574 list_add_tail(§ion->node, sections); 575 return section; 576 } 577 578 static struct perf_config_item *add_config_item(struct perf_config_section *section, 579 const char *name) 580 { 581 struct perf_config_item *item = zalloc(sizeof(*item)); 582 583 if (!item) 584 return NULL; 585 586 item->name = strdup(name); 587 if (!item->name) { 588 pr_debug("%s: strdup failed\n", __func__); 589 free(item); 590 return NULL; 591 } 592 593 list_add_tail(&item->node, §ion->items); 594 return item; 595 } 596 597 static int set_value(struct perf_config_item *item, const char *value) 598 { 599 char *val = strdup(value); 600 601 if (!val) 602 return -1; 603 604 zfree(&item->value); 605 item->value = val; 606 return 0; 607 } 608 609 static int collect_config(const char *var, const char *value, 610 void *perf_config_set) 611 { 612 int ret = -1; 613 char *ptr, *key; 614 char *section_name, *name; 615 struct perf_config_section *section = NULL; 616 struct perf_config_item *item = NULL; 617 struct perf_config_set *set = perf_config_set; 618 struct list_head *sections; 619 620 if (set == NULL) 621 return -1; 622 623 sections = &set->sections; 624 key = ptr = strdup(var); 625 if (!key) { 626 pr_debug("%s: strdup failed\n", __func__); 627 return -1; 628 } 629 630 section_name = strsep(&ptr, "."); 631 name = ptr; 632 if (name == NULL || value == NULL) 633 goto out_free; 634 635 section = find_section(sections, section_name); 636 if (!section) { 637 section = add_section(sections, section_name); 638 if (!section) 639 goto out_free; 640 } 641 642 item = find_config_item(name, section); 643 if (!item) { 644 item = add_config_item(section, name); 645 if (!item) 646 goto out_free; 647 } 648 649 /* perf_config_set can contain both user and system config items. 650 * So we should know where each value is from. 651 * The classification would be needed when a particular config file 652 * is overwrited by setting feature i.e. set_config(). 653 */ 654 if (strcmp(config_file_name, perf_etc_perfconfig()) == 0) { 655 section->from_system_config = true; 656 item->from_system_config = true; 657 } else { 658 section->from_system_config = false; 659 item->from_system_config = false; 660 } 661 662 ret = set_value(item, value); 663 664 out_free: 665 free(key); 666 return ret; 667 } 668 669 int perf_config_set__collect(struct perf_config_set *set, const char *file_name, 670 const char *var, const char *value) 671 { 672 config_file_name = file_name; 673 return collect_config(var, value, set); 674 } 675 676 static int perf_config_set__init(struct perf_config_set *set) 677 { 678 int ret = -1; 679 const char *home = NULL; 680 char *user_config; 681 struct stat st; 682 683 /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */ 684 if (config_exclusive_filename) 685 return perf_config_from_file(collect_config, config_exclusive_filename, set); 686 if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) { 687 if (perf_config_from_file(collect_config, perf_etc_perfconfig(), set) < 0) 688 goto out; 689 } 690 691 home = getenv("HOME"); 692 693 /* 694 * Skip reading user config if: 695 * - there is no place to read it from (HOME) 696 * - we are asked not to (PERF_CONFIG_NOGLOBAL=1) 697 */ 698 if (!home || !*home || !perf_config_global()) 699 return 0; 700 701 user_config = strdup(mkpath("%s/.perfconfig", home)); 702 if (user_config == NULL) { 703 pr_warning("Not enough memory to process %s/.perfconfig, ignoring it.", home); 704 goto out; 705 } 706 707 if (stat(user_config, &st) < 0) { 708 if (errno == ENOENT) 709 ret = 0; 710 goto out_free; 711 } 712 713 ret = 0; 714 715 if (st.st_uid && (st.st_uid != geteuid())) { 716 pr_warning("File %s not owned by current user or root, ignoring it.", user_config); 717 goto out_free; 718 } 719 720 if (st.st_size) 721 ret = perf_config_from_file(collect_config, user_config, set); 722 723 out_free: 724 free(user_config); 725 out: 726 return ret; 727 } 728 729 struct perf_config_set *perf_config_set__new(void) 730 { 731 struct perf_config_set *set = zalloc(sizeof(*set)); 732 733 if (set) { 734 INIT_LIST_HEAD(&set->sections); 735 perf_config_set__init(set); 736 } 737 738 return set; 739 } 740 741 static int perf_config__init(void) 742 { 743 if (config_set == NULL) 744 config_set = perf_config_set__new(); 745 746 return config_set == NULL; 747 } 748 749 int perf_config(config_fn_t fn, void *data) 750 { 751 int ret = 0; 752 char key[BUFSIZ]; 753 struct perf_config_section *section; 754 struct perf_config_item *item; 755 756 if (config_set == NULL && perf_config__init()) 757 return -1; 758 759 perf_config_set__for_each_entry(config_set, section, item) { 760 char *value = item->value; 761 762 if (value) { 763 scnprintf(key, sizeof(key), "%s.%s", 764 section->name, item->name); 765 ret = fn(key, value, data); 766 if (ret < 0) { 767 pr_err("Error: wrong config key-value pair %s=%s\n", 768 key, value); 769 /* 770 * Can't be just a 'break', as perf_config_set__for_each_entry() 771 * expands to two nested for() loops. 772 */ 773 goto out; 774 } 775 } 776 } 777 out: 778 return ret; 779 } 780 781 void perf_config__exit(void) 782 { 783 perf_config_set__delete(config_set); 784 config_set = NULL; 785 } 786 787 void perf_config__refresh(void) 788 { 789 perf_config__exit(); 790 perf_config__init(); 791 } 792 793 static void perf_config_item__delete(struct perf_config_item *item) 794 { 795 zfree(&item->name); 796 zfree(&item->value); 797 free(item); 798 } 799 800 static void perf_config_section__purge(struct perf_config_section *section) 801 { 802 struct perf_config_item *item, *tmp; 803 804 list_for_each_entry_safe(item, tmp, §ion->items, node) { 805 list_del_init(&item->node); 806 perf_config_item__delete(item); 807 } 808 } 809 810 static void perf_config_section__delete(struct perf_config_section *section) 811 { 812 perf_config_section__purge(section); 813 zfree(§ion->name); 814 free(section); 815 } 816 817 static void perf_config_set__purge(struct perf_config_set *set) 818 { 819 struct perf_config_section *section, *tmp; 820 821 list_for_each_entry_safe(section, tmp, &set->sections, node) { 822 list_del_init(§ion->node); 823 perf_config_section__delete(section); 824 } 825 } 826 827 void perf_config_set__delete(struct perf_config_set *set) 828 { 829 if (set == NULL) 830 return; 831 832 perf_config_set__purge(set); 833 free(set); 834 } 835 836 /* 837 * Call this to report error for your variable that should not 838 * get a boolean value (i.e. "[my] var" means "true"). 839 */ 840 int config_error_nonbool(const char *var) 841 { 842 pr_err("Missing value for '%s'", var); 843 return -1; 844 } 845 846 void set_buildid_dir(const char *dir) 847 { 848 if (dir) 849 scnprintf(buildid_dir, MAXPATHLEN, "%s", dir); 850 851 /* default to $HOME/.debug */ 852 if (buildid_dir[0] == '\0') { 853 char *home = getenv("HOME"); 854 855 if (home) { 856 snprintf(buildid_dir, MAXPATHLEN, "%s/%s", 857 home, DEBUG_CACHE_DIR); 858 } else { 859 strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1); 860 } 861 buildid_dir[MAXPATHLEN-1] = '\0'; 862 } 863 /* for communicating with external commands */ 864 setenv("PERF_BUILDID_DIR", buildid_dir, 1); 865 } 866