options.c revision bbca48329c87640e54054c48f87317b637f8477c
1#include "config.h" 2 3#include <sys/ioctl.h> 4#include <assert.h> 5#include <errno.h> 6#include <fcntl.h> 7#include <getopt.h> 8#include <limits.h> 9#include <stdio.h> 10#include <stdlib.h> 11#include <string.h> 12#include <unistd.h> 13 14#include "common.h" 15#include "filter.h" 16#include "glob.h" 17 18#ifndef SYSCONFDIR 19#define SYSCONFDIR "/etc" 20#endif 21 22#define SYSTEM_CONFIG_FILE SYSCONFDIR "/ltrace.conf" 23#define USER_CONFIG_FILE "~/.ltrace.conf" 24 25struct options_t options = { 26 .align = DEFAULT_ALIGN, /* alignment column for results */ 27 .user = NULL, /* username to run command as */ 28 .syscalls = 0, /* display syscalls */ 29#ifdef USE_DEMANGLE 30 .demangle = 0, /* Demangle low-level symbol names */ 31#endif 32 .indent = 0, /* indent output according to program flow */ 33 .output = NULL, /* output to a specific file */ 34 .summary = 0, /* Report a summary on program exit */ 35 .debug = 0, /* debug */ 36 .arraylen = DEFAULT_ARRAYLEN, /* maximum # array elements to print */ 37 .strlen = DEFAULT_STRLEN, /* maximum # of bytes printed in strings */ 38 .follow = 0, /* trace child processes */ 39}; 40 41static char *progname; /* Program name (`ltrace') */ 42int opt_i = 0; /* instruction pointer */ 43int opt_r = 0; /* print relative timestamp */ 44int opt_t = 0; /* print absolute timestamp */ 45int opt_T = 0; /* show the time spent inside each call */ 46 47/* List of pids given to option -p: */ 48struct opt_p_t *opt_p = NULL; /* attach to process with a given pid */ 49 50/* List of filenames give to option -F: */ 51struct opt_F_t *opt_F = NULL; /* alternate configuration file(s) */ 52 53#ifdef PLT_REINITALISATION_BP 54/* Set a break on the routine named here in order to re-initialize breakpoints 55 after all the PLTs have been initialzed */ 56char *PLTs_initialized_by_here = PLT_REINITALISATION_BP; 57#endif 58 59static void 60err_usage(void) { 61 fprintf(stderr, "Try `%s --help' for more information\n", progname); 62 exit(1); 63} 64 65static void 66usage(void) { 67 fprintf(stdout, "Usage: %s [option ...] [command [arg ...]]\n" 68 "Trace library calls of a given program.\n\n" 69 " -a, --align=COLUMN align return values in a secific column.\n" 70 " -A ARRAYLEN maximum number of array elements to print.\n" 71 " -b, --no-signals don't print signals.\n" 72 " -c count time and calls, and report a summary on exit.\n" 73# ifdef USE_DEMANGLE 74 " -C, --demangle decode low-level symbol names into user-level names.\n" 75# endif 76 " -D, --debug=LEVEL enable debugging (see -Dh or --debug=help).\n" 77 " -Dh, --debug=help show help on debugging.\n" 78 " -e expr modify which events to trace.\n" 79 " -f trace children (fork() and clone()).\n" 80 " -F, --config=FILE load alternate configuration file (may be repeated).\n" 81 " -h, --help display this help and exit.\n" 82 " -i print instruction pointer at time of library call.\n" 83 " -l, --library=FILE print library calls from this library only.\n" 84 " -L do NOT display library calls.\n" 85 " -n, --indent=NR indent output by NR spaces for each call level nesting.\n" 86 " -o, --output=FILE write the trace output to that file.\n" 87 " -p PID attach to the process with the process ID pid.\n" 88 " -r print relative timestamps.\n" 89 " -s STRLEN specify the maximum string size to print.\n" 90 " -S display system calls.\n" 91 " -t, -tt, -ttt print absolute timestamps.\n" 92 " -T show the time spent inside each call.\n" 93 " -u USERNAME run command with the userid, groupid of username.\n" 94 " -V, --version output version information and exit.\n" 95#if defined(HAVE_LIBUNWIND) 96 " -w=NR, --where=NR print backtrace showing NR stack frames at most.\n" 97#endif /* defined(HAVE_LIBUNWIND) */ 98 " -x NAME treat the global NAME like a library subroutine.\n" 99#ifdef PLT_REINITALISATION_BP 100 " -X NAME same as -x; and PLT's will be initialized by here.\n" 101#endif 102 "\nReport bugs to ltrace-devel@lists.alioth.debian.org\n", 103 progname); 104} 105 106static void 107usage_debug(void) { 108 fprintf(stdout, "%s debugging option, --debug=<octal> or -D<octal>:\n", progname); 109 fprintf(stdout, 110 "\n" 111 " number ref. in source description\n" 112 " 1 general Generally helpful progress information\n" 113 " 10 event Shows every event received by a traced process\n" 114 " 20 process Shows actions carried upon a traced processes\n" 115 " 40 function Shows every entry to internal functions\n" 116 "\n" 117 "Debugging options are mixed using bitwise-or.\n" 118 "Note that the meanings and values are subject to change.\n" 119 ); 120} 121 122static char * 123search_for_command(char *filename) { 124 static char pathname[PATH_MAX]; 125 char *path; 126 int m, n; 127 128 if (strchr(filename, '/')) { 129 return filename; 130 } 131 for (path = getenv("PATH"); path && *path; path += m) { 132 if (strchr(path, ':')) { 133 n = strchr(path, ':') - path; 134 m = n + 1; 135 } else { 136 m = n = strlen(path); 137 } 138 if (n + strlen(filename) + 1 >= PATH_MAX) { 139 fprintf(stderr, "Error: filename too long\n"); 140 exit(1); 141 } 142 strncpy(pathname, path, n); 143 if (n && pathname[n - 1] != '/') { 144 pathname[n++] = '/'; 145 } 146 strcpy(pathname + n, filename); 147 if (!access(pathname, X_OK)) { 148 return pathname; 149 } 150 } 151 return filename; 152} 153 154static void 155guess_cols(void) { 156 struct winsize ws; 157 char *c; 158 159 options.align = DEFAULT_ALIGN; 160 c = getenv("COLUMNS"); 161 if (c && *c) { 162 char *endptr; 163 int cols; 164 cols = strtol(c, &endptr, 0); 165 if (cols > 0 && !*endptr) { 166 options.align = cols * 5 / 8; 167 } 168 } else if (ioctl(1, TIOCGWINSZ, &ws) != -1 && ws.ws_col > 0) { 169 options.align = ws.ws_col * 5 / 8; 170 } else if (ioctl(2, TIOCGWINSZ, &ws) != -1 && ws.ws_col > 0) { 171 options.align = ws.ws_col * 5 / 8; 172 } 173} 174 175static void 176add_filter_rule(struct filter *filt, const char *expr, 177 enum filter_rule_type type, 178 const char *a_sym, int sym_re_p, 179 const char *a_lib, int lib_re_p) 180{ 181 struct filter_rule *rule = malloc(sizeof(*rule)); 182 struct filter_lib_matcher *matcher = malloc(sizeof(*matcher)); 183 184 if (rule == NULL || matcher == NULL) { 185 fprintf(stderr, "rule near '%s' will be ignored: %s\n", 186 expr, strerror(errno)); 187 fail: 188 free(rule); 189 free(matcher); 190 return; 191 } 192 193 regex_t symbol_re; 194 int status; 195 { 196 /* Add ^ to the start of expression and $ to the end, so that 197 * we match the whole symbol name. Let the user write the "*" 198 * explicitly if they wish. */ 199 char sym[strlen(a_sym) + 3]; 200 sprintf(sym, "^%s$", a_sym); 201 status = (sym_re_p ? regcomp : globcomp)(&symbol_re, sym, 0); 202 if (status != 0) { 203 char buf[100]; 204 regerror(status, &symbol_re, buf, sizeof buf); 205 fprintf(stderr, "rule near '%s' will be ignored: %s\n", 206 expr, buf); 207 goto fail; 208 } 209 } 210 211 if (strcmp(a_lib, "MAIN") == 0) { 212 filter_lib_matcher_main_init(matcher); 213 } else { 214 /* Add ^ and $ to the library expression as well. */ 215 char lib[strlen(a_lib) + 3]; 216 sprintf(lib, "^%s$", a_lib); 217 218 enum filter_lib_matcher_type type 219 = lib[0] == '/' ? FLM_PATHNAME : FLM_SONAME; 220 221 regex_t lib_re; 222 status = (lib_re_p ? regcomp : globcomp)(&lib_re, lib, 0); 223 if (status != 0) { 224 char buf[100]; 225 regerror(status, &lib_re, buf, sizeof buf); 226 fprintf(stderr, "rule near '%s' will be ignored: %s\n", 227 expr, buf); 228 229 regfree(&symbol_re); 230 goto fail; 231 } 232 filter_lib_matcher_name_init(matcher, type, lib_re); 233 } 234 235 filter_rule_init(rule, type, matcher, symbol_re); 236 filter_add_rule(filt, rule); 237} 238 239static int 240parse_filter(struct filter *filt, char *expr) 241{ 242 /* Filter is a chain of sym@lib rules separated by '-'. If 243 * the filter expression starts with '-', the missing initial 244 * rule is implicitly *@*. */ 245 246 enum filter_rule_type type = FR_ADD; 247 248 while (*expr != 0) { 249 size_t s = strcspn(expr, "@-+"); 250 char *symname = expr; 251 char *libname; 252 char *next = expr + s + 1; 253 enum filter_rule_type this_type = type; 254 255 if (expr[s] == 0) { 256 libname = "*"; 257 expr = next - 1; 258 259 } else if (expr[s] == '-' || expr[s] == '+') { 260 type = expr[s] == '-' ? FR_SUBTRACT : FR_ADD; 261 expr[s] = 0; 262 libname = "*"; 263 expr = next; 264 265 } else { 266 assert(expr[s] == '@'); 267 expr[s] = 0; 268 s = strcspn(next, "-+"); 269 if (s == 0) { 270 libname = "*"; 271 expr = next; 272 } else if (next[s] == 0) { 273 expr = next + s; 274 libname = next; 275 } else { 276 assert(next[s] == '-' || next[s] == '+'); 277 type = next[s] == '-' ? FR_SUBTRACT : FR_ADD; 278 next[s] = 0; 279 expr = next + s + 1; 280 libname = next; 281 } 282 } 283 284 assert(*libname != 0); 285 char *symend = symname + strlen(symname) - 1; 286 char *libend = libname + strlen(libname) - 1; 287 int sym_is_re = 0; 288 int lib_is_re = 0; 289 290 /* 291 * /xxx/@... and ...@/xxx/ means that xxx are regular 292 * expressions. They are globs otherwise. 293 * 294 * /xxx@yyy/ is the same as /xxx/@/yyy/ 295 * 296 * @/xxx matches library path name 297 * @.xxx matches library relative path name 298 */ 299 if (symname[0] == '/') { 300 if (symname != symend && symend[0] == '/') { 301 ++symname; 302 *symend-- = 0; 303 sym_is_re = 1; 304 305 } else { 306 sym_is_re = 1; 307 lib_is_re = 1; 308 ++symname; 309 310 /* /XXX@YYY/ is the same as 311 * /XXX/@/YYY/. */ 312 if (libend[0] != '/') 313 fprintf(stderr, "unmatched '/'" 314 " in symbol name\n"); 315 else 316 *libend-- = 0; 317 } 318 } 319 320 /* If libname ends in '/', then we expect '/' in the 321 * beginning too. Otherwise the initial '/' is part 322 * of absolute file name. */ 323 if (!lib_is_re && libend[0] == '/') { 324 lib_is_re = 1; 325 *libend-- = 0; 326 if (libname != libend && libname[0] == '/') 327 ++libname; 328 else 329 fprintf(stderr, "unmatched '/'" 330 " in library name\n"); 331 } 332 333 if (*symname == 0) /* /@AA/ */ 334 symname = "*"; 335 if (*libname == 0) /* /aa@/ */ 336 libname = "*"; 337 338 add_filter_rule(filt, expr, this_type, 339 symname, sym_is_re, 340 libname, lib_is_re); 341 } 342 343 return 0; 344} 345 346static struct filter * 347recursive_parse_chain(char *expr) 348{ 349 struct filter *filt = malloc(sizeof(*filt)); 350 if (filt == NULL) { 351 fprintf(stderr, "(part of) filter will be ignored: '%s': %s\n", 352 expr, strerror(errno)); 353 return NULL; 354 } 355 356 filter_init(filt); 357 if (parse_filter(filt, expr) < 0) { 358 fprintf(stderr, "Filter '%s' will be ignored.\n", expr); 359 free(filt); 360 filt = NULL; 361 } 362 363 return filt; 364} 365 366static void 367parse_filter_chain(const char *expr, struct filter **retp) 368{ 369 char *str = strdup(expr); 370 if (str == NULL) { 371 fprintf(stderr, "filter '%s' will be ignored: %s\n", 372 expr, strerror(errno)); 373 return; 374 } 375 /* Support initial '!' for backward compatibility. */ 376 if (str[0] == '!') 377 str[0] = '-'; 378 379 struct filter **tailp; 380 for (tailp = retp; *tailp != NULL; tailp = &(*tailp)->next) 381 ; 382 *tailp = recursive_parse_chain(str); 383} 384 385char ** 386process_options(int argc, char **argv) 387{ 388 progname = argv[0]; 389 options.output = stderr; 390 options.no_signals = 0; 391#if defined(HAVE_LIBUNWIND) 392 options.bt_depth = -1; 393#endif /* defined(HAVE_LIBUNWIND) */ 394 395 guess_cols(); 396 397 int libcalls = 1; 398 399 while (1) { 400 int c; 401 char *p; 402 int option_index = 0; 403 static struct option long_options[] = { 404 {"align", 1, 0, 'a'}, 405 {"config", 1, 0, 'F'}, 406 {"debug", 1, 0, 'D'}, 407# ifdef USE_DEMANGLE 408 {"demangle", 0, 0, 'C'}, 409#endif 410 {"indent", 1, 0, 'n'}, 411 {"help", 0, 0, 'h'}, 412 {"library", 1, 0, 'l'}, 413 {"output", 1, 0, 'o'}, 414 {"version", 0, 0, 'V'}, 415 {"no-signals", 0, 0, 'b'}, 416#if defined(HAVE_LIBUNWIND) 417 {"where", 1, 0, 'w'}, 418#endif /* defined(HAVE_LIBUNWIND) */ 419 {0, 0, 0, 0} 420 }; 421 c = getopt_long(argc, argv, "+cfhiLrStTVb" 422# ifdef USE_DEMANGLE 423 "C" 424# endif 425#if defined(HAVE_LIBUNWIND) 426 "a:A:D:e:F:l:n:o:p:s:u:x:X:w:", long_options, 427#else /* !defined(HAVE_LIBUNWIND) */ 428 "a:A:D:e:F:l:n:o:p:s:u:x:X:", long_options, 429#endif 430 &option_index); 431 if (c == -1) { 432 break; 433 } 434 switch (c) { 435 case 'a': 436 options.align = atoi(optarg); 437 break; 438 case 'A': 439 options.arraylen = atoi(optarg); 440 break; 441 case 'b': 442 options.no_signals = 1; 443 break; 444 case 'c': 445 options.summary++; 446 break; 447#ifdef USE_DEMANGLE 448 case 'C': 449 options.demangle++; 450 break; 451#endif 452 case 'D': 453 if (optarg[0]=='h') { 454 usage_debug(); 455 exit(0); 456 } 457 options.debug = strtoul(optarg,&p,8); 458 if (*p) { 459 fprintf(stderr, "%s: --debug requires an octal argument\n", progname); 460 err_usage(); 461 } 462 break; 463 464 case 'e': 465 parse_filter_chain(optarg, &options.plt_filter); 466 break; 467 468 case 'f': 469 options.follow = 1; 470 break; 471 case 'F': 472 { 473 struct opt_F_t *tmp = malloc(sizeof(struct opt_F_t)); 474 if (!tmp) { 475 perror("ltrace: malloc"); 476 exit(1); 477 } 478 tmp->filename = strdup(optarg); 479 tmp->next = opt_F; 480 opt_F = tmp; 481 break; 482 } 483 case 'h': 484 usage(); 485 exit(0); 486 case 'i': 487 opt_i++; 488 break; 489 case 'l': 490 // XXX TODO 491 fprintf(stderr, "-l support not yet implemented\n"); 492 break; 493 case 'L': 494 libcalls = 0; 495 break; 496 case 'n': { 497 char *endptr; 498 long int l = strtol(optarg, &endptr, 0); 499 /* Arbitrary cut-off. Nobody needs to indent 500 * more than, say, 8, anyway. */ 501 if (l < 0 || l > 20 || *optarg == 0 || *endptr != 0) { 502 fprintf(stderr, "Invalid argument to -n: '%s'." 503 " Use integer 0..20.\n", optarg); 504 exit(1); 505 } 506 options.indent = (int)l; 507 break; 508 } 509 case 'o': 510 options.output = fopen(optarg, "w"); 511 if (!options.output) { 512 fprintf(stderr, 513 "can't open %s for writing: %s\n", 514 optarg, strerror(errno)); 515 exit(1); 516 } 517 setvbuf(options.output, (char *)NULL, _IOLBF, 0); 518 fcntl(fileno(options.output), F_SETFD, FD_CLOEXEC); 519 break; 520 case 'p': 521 { 522 struct opt_p_t *tmp = malloc(sizeof(struct opt_p_t)); 523 if (!tmp) { 524 perror("ltrace: malloc"); 525 exit(1); 526 } 527 tmp->pid = atoi(optarg); 528 tmp->next = opt_p; 529 opt_p = tmp; 530 break; 531 } 532 case 'r': 533 opt_r++; 534 break; 535 case 's': 536 options.strlen = atoi(optarg); 537 break; 538 case 'S': 539 options.syscalls = 1; 540 break; 541 case 't': 542 opt_t++; 543 break; 544 case 'T': 545 opt_T++; 546 break; 547 case 'u': 548 options.user = optarg; 549 break; 550 case 'V': 551 printf("ltrace version " PACKAGE_VERSION ".\n" 552 "Copyright (C) 1997-2009 Juan Cespedes <cespedes@debian.org>.\n" 553 "This is free software; see the GNU General Public Licence\n" 554 "version 2 or later for copying conditions. There is NO warranty.\n"); 555 exit(0); 556 break; 557#if defined(HAVE_LIBUNWIND) 558 case 'w': 559 options.bt_depth = atoi(optarg); 560 break; 561#endif /* defined(HAVE_LIBUNWIND) */ 562 case 'X': 563#ifdef PLT_REINITALISATION_BP 564 PLTs_initialized_by_here = optarg; 565#else 566 fprintf(stderr, "WARNING: \"-X\" not used for this " 567 "architecture: assuming you meant \"-x\"\n"); 568#endif 569 /* Fall Thru */ 570 571 case 'x': 572 parse_filter_chain(optarg, &options.static_filter); 573 break; 574 575 default: 576 err_usage(); 577 } 578 } 579 argc -= optind; 580 argv += optind; 581 582 if (!opt_F) { 583 opt_F = malloc(sizeof(struct opt_F_t)); 584 opt_F->next = malloc(sizeof(struct opt_F_t)); 585 opt_F->next->next = NULL; 586 opt_F->filename = USER_CONFIG_FILE; 587 opt_F->next->filename = SYSTEM_CONFIG_FILE; 588 } 589 /* Reverse the config file list since it was built by 590 * prepending, and it would make more sense to process the 591 * files in the order they were given. Probably it would make 592 * more sense to keep a tail pointer instead? */ 593 { 594 struct opt_F_t *egg = NULL; 595 struct opt_F_t *chicken; 596 while (opt_F) { 597 chicken = opt_F->next; 598 opt_F->next = egg; 599 egg = opt_F; 600 opt_F = chicken; 601 } 602 opt_F = egg; 603 } 604 605 /* Set default filter. Use @MAIN for now, as that's what 606 * ltrace used to have in the past. XXX Maybe we should make 607 * this "*" instead. */ 608 if (options.plt_filter == NULL && libcalls) { 609 parse_filter_chain("@MAIN", &options.plt_filter); 610 options.hide_caller = 1; 611 } 612 613 if (!opt_p && argc < 1) { 614 fprintf(stderr, "%s: too few arguments\n", progname); 615 err_usage(); 616 } 617 if (opt_r && opt_t) { 618 fprintf(stderr, "%s: Incompatible options -r and -t\n", 619 progname); 620 err_usage(); 621 } 622 if (argc > 0) { 623 command = search_for_command(argv[0]); 624 } 625 return &argv[0]; 626} 627