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