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