1 /* 2 * builtin-help.c 3 * 4 * Builtin help command 5 */ 6 #include "perf.h" 7 #include "util/cache.h" 8 #include "builtin.h" 9 #include <subcmd/exec-cmd.h> 10 #include "common-cmds.h" 11 #include <subcmd/parse-options.h> 12 #include <subcmd/run-command.h> 13 #include <subcmd/help.h> 14 #include "util/debug.h" 15 16 static struct man_viewer_list { 17 struct man_viewer_list *next; 18 char name[FLEX_ARRAY]; 19 } *man_viewer_list; 20 21 static struct man_viewer_info_list { 22 struct man_viewer_info_list *next; 23 const char *info; 24 char name[FLEX_ARRAY]; 25 } *man_viewer_info_list; 26 27 enum help_format { 28 HELP_FORMAT_NONE, 29 HELP_FORMAT_MAN, 30 HELP_FORMAT_INFO, 31 HELP_FORMAT_WEB, 32 }; 33 34 static enum help_format parse_help_format(const char *format) 35 { 36 if (!strcmp(format, "man")) 37 return HELP_FORMAT_MAN; 38 if (!strcmp(format, "info")) 39 return HELP_FORMAT_INFO; 40 if (!strcmp(format, "web") || !strcmp(format, "html")) 41 return HELP_FORMAT_WEB; 42 43 pr_err("unrecognized help format '%s'", format); 44 return HELP_FORMAT_NONE; 45 } 46 47 static const char *get_man_viewer_info(const char *name) 48 { 49 struct man_viewer_info_list *viewer; 50 51 for (viewer = man_viewer_info_list; viewer; viewer = viewer->next) { 52 if (!strcasecmp(name, viewer->name)) 53 return viewer->info; 54 } 55 return NULL; 56 } 57 58 static int check_emacsclient_version(void) 59 { 60 struct strbuf buffer = STRBUF_INIT; 61 struct child_process ec_process; 62 const char *argv_ec[] = { "emacsclient", "--version", NULL }; 63 int version; 64 65 /* emacsclient prints its version number on stderr */ 66 memset(&ec_process, 0, sizeof(ec_process)); 67 ec_process.argv = argv_ec; 68 ec_process.err = -1; 69 ec_process.stdout_to_stderr = 1; 70 if (start_command(&ec_process)) { 71 fprintf(stderr, "Failed to start emacsclient.\n"); 72 return -1; 73 } 74 strbuf_read(&buffer, ec_process.err, 20); 75 close(ec_process.err); 76 77 /* 78 * Don't bother checking return value, because "emacsclient --version" 79 * seems to always exits with code 1. 80 */ 81 finish_command(&ec_process); 82 83 if (prefixcmp(buffer.buf, "emacsclient")) { 84 fprintf(stderr, "Failed to parse emacsclient version.\n"); 85 strbuf_release(&buffer); 86 return -1; 87 } 88 89 version = atoi(buffer.buf + strlen("emacsclient")); 90 91 if (version < 22) { 92 fprintf(stderr, 93 "emacsclient version '%d' too old (< 22).\n", 94 version); 95 strbuf_release(&buffer); 96 return -1; 97 } 98 99 strbuf_release(&buffer); 100 return 0; 101 } 102 103 static void exec_woman_emacs(const char *path, const char *page) 104 { 105 char sbuf[STRERR_BUFSIZE]; 106 107 if (!check_emacsclient_version()) { 108 /* This works only with emacsclient version >= 22. */ 109 struct strbuf man_page = STRBUF_INIT; 110 111 if (!path) 112 path = "emacsclient"; 113 strbuf_addf(&man_page, "(woman \"%s\")", page); 114 execlp(path, "emacsclient", "-e", man_page.buf, NULL); 115 warning("failed to exec '%s': %s", path, 116 strerror_r(errno, sbuf, sizeof(sbuf))); 117 } 118 } 119 120 static void exec_man_konqueror(const char *path, const char *page) 121 { 122 const char *display = getenv("DISPLAY"); 123 124 if (display && *display) { 125 struct strbuf man_page = STRBUF_INIT; 126 const char *filename = "kfmclient"; 127 char sbuf[STRERR_BUFSIZE]; 128 129 /* It's simpler to launch konqueror using kfmclient. */ 130 if (path) { 131 const char *file = strrchr(path, '/'); 132 if (file && !strcmp(file + 1, "konqueror")) { 133 char *new = strdup(path); 134 char *dest = strrchr(new, '/'); 135 136 /* strlen("konqueror") == strlen("kfmclient") */ 137 strcpy(dest + 1, "kfmclient"); 138 path = new; 139 } 140 if (file) 141 filename = file; 142 } else 143 path = "kfmclient"; 144 strbuf_addf(&man_page, "man:%s(1)", page); 145 execlp(path, filename, "newTab", man_page.buf, NULL); 146 warning("failed to exec '%s': %s", path, 147 strerror_r(errno, sbuf, sizeof(sbuf))); 148 } 149 } 150 151 static void exec_man_man(const char *path, const char *page) 152 { 153 char sbuf[STRERR_BUFSIZE]; 154 155 if (!path) 156 path = "man"; 157 execlp(path, "man", page, NULL); 158 warning("failed to exec '%s': %s", path, 159 strerror_r(errno, sbuf, sizeof(sbuf))); 160 } 161 162 static void exec_man_cmd(const char *cmd, const char *page) 163 { 164 struct strbuf shell_cmd = STRBUF_INIT; 165 char sbuf[STRERR_BUFSIZE]; 166 167 strbuf_addf(&shell_cmd, "%s %s", cmd, page); 168 execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL); 169 warning("failed to exec '%s': %s", cmd, 170 strerror_r(errno, sbuf, sizeof(sbuf))); 171 } 172 173 static void add_man_viewer(const char *name) 174 { 175 struct man_viewer_list **p = &man_viewer_list; 176 size_t len = strlen(name); 177 178 while (*p) 179 p = &((*p)->next); 180 *p = zalloc(sizeof(**p) + len + 1); 181 strncpy((*p)->name, name, len); 182 } 183 184 static int supported_man_viewer(const char *name, size_t len) 185 { 186 return (!strncasecmp("man", name, len) || 187 !strncasecmp("woman", name, len) || 188 !strncasecmp("konqueror", name, len)); 189 } 190 191 static void do_add_man_viewer_info(const char *name, 192 size_t len, 193 const char *value) 194 { 195 struct man_viewer_info_list *new = zalloc(sizeof(*new) + len + 1); 196 197 strncpy(new->name, name, len); 198 new->info = strdup(value); 199 new->next = man_viewer_info_list; 200 man_viewer_info_list = new; 201 } 202 203 static int add_man_viewer_path(const char *name, 204 size_t len, 205 const char *value) 206 { 207 if (supported_man_viewer(name, len)) 208 do_add_man_viewer_info(name, len, value); 209 else 210 warning("'%s': path for unsupported man viewer.\n" 211 "Please consider using 'man.<tool>.cmd' instead.", 212 name); 213 214 return 0; 215 } 216 217 static int add_man_viewer_cmd(const char *name, 218 size_t len, 219 const char *value) 220 { 221 if (supported_man_viewer(name, len)) 222 warning("'%s': cmd for supported man viewer.\n" 223 "Please consider using 'man.<tool>.path' instead.", 224 name); 225 else 226 do_add_man_viewer_info(name, len, value); 227 228 return 0; 229 } 230 231 static int add_man_viewer_info(const char *var, const char *value) 232 { 233 const char *name = var + 4; 234 const char *subkey = strrchr(name, '.'); 235 236 if (!subkey) 237 return error("Config with no key for man viewer: %s", name); 238 239 if (!strcmp(subkey, ".path")) { 240 if (!value) 241 return config_error_nonbool(var); 242 return add_man_viewer_path(name, subkey - name, value); 243 } 244 if (!strcmp(subkey, ".cmd")) { 245 if (!value) 246 return config_error_nonbool(var); 247 return add_man_viewer_cmd(name, subkey - name, value); 248 } 249 250 warning("'%s': unsupported man viewer sub key.", subkey); 251 return 0; 252 } 253 254 static int perf_help_config(const char *var, const char *value, void *cb) 255 { 256 enum help_format *help_formatp = cb; 257 258 if (!strcmp(var, "help.format")) { 259 if (!value) 260 return config_error_nonbool(var); 261 *help_formatp = parse_help_format(value); 262 if (*help_formatp == HELP_FORMAT_NONE) 263 return -1; 264 return 0; 265 } 266 if (!strcmp(var, "man.viewer")) { 267 if (!value) 268 return config_error_nonbool(var); 269 add_man_viewer(value); 270 return 0; 271 } 272 if (!prefixcmp(var, "man.")) 273 return add_man_viewer_info(var, value); 274 275 return perf_default_config(var, value, cb); 276 } 277 278 static struct cmdnames main_cmds, other_cmds; 279 280 void list_common_cmds_help(void) 281 { 282 unsigned int i, longest = 0; 283 284 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) { 285 if (longest < strlen(common_cmds[i].name)) 286 longest = strlen(common_cmds[i].name); 287 } 288 289 puts(" The most commonly used perf commands are:"); 290 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) { 291 printf(" %-*s ", longest, common_cmds[i].name); 292 puts(common_cmds[i].help); 293 } 294 } 295 296 static int is_perf_command(const char *s) 297 { 298 return is_in_cmdlist(&main_cmds, s) || 299 is_in_cmdlist(&other_cmds, s); 300 } 301 302 static const char *prepend(const char *prefix, const char *cmd) 303 { 304 size_t pre_len = strlen(prefix); 305 size_t cmd_len = strlen(cmd); 306 char *p = malloc(pre_len + cmd_len + 1); 307 memcpy(p, prefix, pre_len); 308 strcpy(p + pre_len, cmd); 309 return p; 310 } 311 312 static const char *cmd_to_page(const char *perf_cmd) 313 { 314 if (!perf_cmd) 315 return "perf"; 316 else if (!prefixcmp(perf_cmd, "perf")) 317 return perf_cmd; 318 else 319 return prepend("perf-", perf_cmd); 320 } 321 322 static void setup_man_path(void) 323 { 324 struct strbuf new_path = STRBUF_INIT; 325 const char *old_path = getenv("MANPATH"); 326 327 /* We should always put ':' after our path. If there is no 328 * old_path, the ':' at the end will let 'man' to try 329 * system-wide paths after ours to find the manual page. If 330 * there is old_path, we need ':' as delimiter. */ 331 strbuf_addstr(&new_path, system_path(PERF_MAN_PATH)); 332 strbuf_addch(&new_path, ':'); 333 if (old_path) 334 strbuf_addstr(&new_path, old_path); 335 336 setenv("MANPATH", new_path.buf, 1); 337 338 strbuf_release(&new_path); 339 } 340 341 static void exec_viewer(const char *name, const char *page) 342 { 343 const char *info = get_man_viewer_info(name); 344 345 if (!strcasecmp(name, "man")) 346 exec_man_man(info, page); 347 else if (!strcasecmp(name, "woman")) 348 exec_woman_emacs(info, page); 349 else if (!strcasecmp(name, "konqueror")) 350 exec_man_konqueror(info, page); 351 else if (info) 352 exec_man_cmd(info, page); 353 else 354 warning("'%s': unknown man viewer.", name); 355 } 356 357 static int show_man_page(const char *perf_cmd) 358 { 359 struct man_viewer_list *viewer; 360 const char *page = cmd_to_page(perf_cmd); 361 const char *fallback = getenv("PERF_MAN_VIEWER"); 362 363 setup_man_path(); 364 for (viewer = man_viewer_list; viewer; viewer = viewer->next) 365 exec_viewer(viewer->name, page); /* will return when unable */ 366 367 if (fallback) 368 exec_viewer(fallback, page); 369 exec_viewer("man", page); 370 371 pr_err("no man viewer handled the request"); 372 return -1; 373 } 374 375 static int show_info_page(const char *perf_cmd) 376 { 377 const char *page = cmd_to_page(perf_cmd); 378 setenv("INFOPATH", system_path(PERF_INFO_PATH), 1); 379 execlp("info", "info", "perfman", page, NULL); 380 return -1; 381 } 382 383 static int get_html_page_path(struct strbuf *page_path, const char *page) 384 { 385 struct stat st; 386 const char *html_path = system_path(PERF_HTML_PATH); 387 388 /* Check that we have a perf documentation directory. */ 389 if (stat(mkpath("%s/perf.html", html_path), &st) 390 || !S_ISREG(st.st_mode)) { 391 pr_err("'%s': not a documentation directory.", html_path); 392 return -1; 393 } 394 395 strbuf_init(page_path, 0); 396 strbuf_addf(page_path, "%s/%s.html", html_path, page); 397 398 return 0; 399 } 400 401 /* 402 * If open_html is not defined in a platform-specific way (see for 403 * example compat/mingw.h), we use the script web--browse to display 404 * HTML. 405 */ 406 #ifndef open_html 407 static void open_html(const char *path) 408 { 409 execl_cmd("web--browse", "-c", "help.browser", path, NULL); 410 } 411 #endif 412 413 static int show_html_page(const char *perf_cmd) 414 { 415 const char *page = cmd_to_page(perf_cmd); 416 struct strbuf page_path; /* it leaks but we exec bellow */ 417 418 if (get_html_page_path(&page_path, page) != 0) 419 return -1; 420 421 open_html(page_path.buf); 422 423 return 0; 424 } 425 426 int cmd_help(int argc, const char **argv, const char *prefix __maybe_unused) 427 { 428 bool show_all = false; 429 enum help_format help_format = HELP_FORMAT_MAN; 430 struct option builtin_help_options[] = { 431 OPT_BOOLEAN('a', "all", &show_all, "print all available commands"), 432 OPT_SET_UINT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN), 433 OPT_SET_UINT('w', "web", &help_format, "show manual in web browser", 434 HELP_FORMAT_WEB), 435 OPT_SET_UINT('i', "info", &help_format, "show info page", 436 HELP_FORMAT_INFO), 437 OPT_END(), 438 }; 439 const char * const builtin_help_subcommands[] = { 440 "buildid-cache", "buildid-list", "diff", "evlist", "help", "list", 441 "record", "report", "bench", "stat", "timechart", "top", "annotate", 442 "script", "sched", "kmem", "lock", "kvm", "test", "inject", "mem", "data", 443 #ifdef HAVE_LIBELF_SUPPORT 444 "probe", 445 #endif 446 #ifdef HAVE_LIBAUDIT_SUPPORT 447 "trace", 448 #endif 449 NULL }; 450 const char *builtin_help_usage[] = { 451 "perf help [--all] [--man|--web|--info] [command]", 452 NULL 453 }; 454 const char *alias; 455 int rc = 0; 456 457 load_command_list("perf-", &main_cmds, &other_cmds); 458 459 perf_config(perf_help_config, &help_format); 460 461 argc = parse_options_subcommand(argc, argv, builtin_help_options, 462 builtin_help_subcommands, builtin_help_usage, 0); 463 464 if (show_all) { 465 printf("\n Usage: %s\n\n", perf_usage_string); 466 list_commands("perf commands", &main_cmds, &other_cmds); 467 printf(" %s\n\n", perf_more_info_string); 468 return 0; 469 } 470 471 if (!argv[0]) { 472 printf("\n usage: %s\n\n", perf_usage_string); 473 list_common_cmds_help(); 474 printf("\n %s\n\n", perf_more_info_string); 475 return 0; 476 } 477 478 alias = alias_lookup(argv[0]); 479 if (alias && !is_perf_command(argv[0])) { 480 printf("`perf %s' is aliased to `%s'\n", argv[0], alias); 481 return 0; 482 } 483 484 switch (help_format) { 485 case HELP_FORMAT_MAN: 486 rc = show_man_page(argv[0]); 487 break; 488 case HELP_FORMAT_INFO: 489 rc = show_info_page(argv[0]); 490 break; 491 case HELP_FORMAT_WEB: 492 rc = show_html_page(argv[0]); 493 break; 494 case HELP_FORMAT_NONE: 495 /* fall-through */ 496 default: 497 rc = -1; 498 break; 499 } 500 501 return rc; 502 } 503