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 { 66 if (!strcasecmp(name, viewer->name)) 67 return viewer->info; 68 } 69 return NULL; 70 } 71 72 static int check_emacsclient_version(void) 73 { 74 struct strbuf buffer = STRBUF_INIT; 75 struct child_process ec_process; 76 const char *argv_ec[] = { "emacsclient", "--version", NULL }; 77 int version; 78 79 /* emacsclient prints its version number on stderr */ 80 memset(&ec_process, 0, sizeof(ec_process)); 81 ec_process.argv = argv_ec; 82 ec_process.err = -1; 83 ec_process.stdout_to_stderr = 1; 84 if (start_command(&ec_process)) { 85 fprintf(stderr, "Failed to start emacsclient.\n"); 86 return -1; 87 } 88 strbuf_read(&buffer, ec_process.err, 20); 89 close(ec_process.err); 90 91 /* 92 * Don't bother checking return value, because "emacsclient --version" 93 * seems to always exits with code 1. 94 */ 95 finish_command(&ec_process); 96 97 if (prefixcmp(buffer.buf, "emacsclient")) { 98 fprintf(stderr, "Failed to parse emacsclient version.\n"); 99 strbuf_release(&buffer); 100 return -1; 101 } 102 103 strbuf_remove(&buffer, 0, strlen("emacsclient")); 104 version = atoi(buffer.buf); 105 106 if (version < 22) { 107 fprintf(stderr, 108 "emacsclient version '%d' too old (< 22).\n", 109 version); 110 strbuf_release(&buffer); 111 return -1; 112 } 113 114 strbuf_release(&buffer); 115 return 0; 116 } 117 118 static void exec_woman_emacs(const char* path, const char *page) 119 { 120 if (!check_emacsclient_version()) { 121 /* This works only with emacsclient version >= 22. */ 122 struct strbuf man_page = STRBUF_INIT; 123 124 if (!path) 125 path = "emacsclient"; 126 strbuf_addf(&man_page, "(woman \"%s\")", page); 127 execlp(path, "emacsclient", "-e", man_page.buf, NULL); 128 warning("failed to exec '%s': %s", path, strerror(errno)); 129 } 130 } 131 132 static void exec_man_konqueror(const char* path, const char *page) 133 { 134 const char *display = getenv("DISPLAY"); 135 if (display && *display) { 136 struct strbuf man_page = STRBUF_INIT; 137 const char *filename = "kfmclient"; 138 139 /* It's simpler to launch konqueror using kfmclient. */ 140 if (path) { 141 const char *file = strrchr(path, '/'); 142 if (file && !strcmp(file + 1, "konqueror")) { 143 char *new = strdup(path); 144 char *dest = strrchr(new, '/'); 145 146 /* strlen("konqueror") == strlen("kfmclient") */ 147 strcpy(dest + 1, "kfmclient"); 148 path = new; 149 } 150 if (file) 151 filename = file; 152 } else 153 path = "kfmclient"; 154 strbuf_addf(&man_page, "man:%s(1)", page); 155 execlp(path, filename, "newTab", man_page.buf, NULL); 156 warning("failed to exec '%s': %s", path, strerror(errno)); 157 } 158 } 159 160 static void exec_man_man(const char* path, const char *page) 161 { 162 if (!path) 163 path = "man"; 164 execlp(path, "man", page, NULL); 165 warning("failed to exec '%s': %s", path, strerror(errno)); 166 } 167 168 static void exec_man_cmd(const char *cmd, const char *page) 169 { 170 struct strbuf shell_cmd = STRBUF_INIT; 171 strbuf_addf(&shell_cmd, "%s %s", cmd, page); 172 execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL); 173 warning("failed to exec '%s': %s", cmd, strerror(errno)); 174 } 175 176 static void add_man_viewer(const char *name) 177 { 178 struct man_viewer_list **p = &man_viewer_list; 179 size_t len = strlen(name); 180 181 while (*p) 182 p = &((*p)->next); 183 *p = calloc(1, (sizeof(**p) + len + 1)); 184 strncpy((*p)->name, name, len); 185 } 186 187 static int supported_man_viewer(const char *name, size_t len) 188 { 189 return (!strncasecmp("man", name, len) || 190 !strncasecmp("woman", name, len) || 191 !strncasecmp("konqueror", name, len)); 192 } 193 194 static void do_add_man_viewer_info(const char *name, 195 size_t len, 196 const char *value) 197 { 198 struct man_viewer_info_list *new = calloc(1, sizeof(*new) + len + 1); 199 200 strncpy(new->name, name, len); 201 new->info = strdup(value); 202 new->next = man_viewer_info_list; 203 man_viewer_info_list = new; 204 } 205 206 static int add_man_viewer_path(const char *name, 207 size_t len, 208 const char *value) 209 { 210 if (supported_man_viewer(name, len)) 211 do_add_man_viewer_info(name, len, value); 212 else 213 warning("'%s': path for unsupported man viewer.\n" 214 "Please consider using 'man.<tool>.cmd' instead.", 215 name); 216 217 return 0; 218 } 219 220 static int add_man_viewer_cmd(const char *name, 221 size_t len, 222 const char *value) 223 { 224 if (supported_man_viewer(name, len)) 225 warning("'%s': cmd for supported man viewer.\n" 226 "Please consider using 'man.<tool>.path' instead.", 227 name); 228 else 229 do_add_man_viewer_info(name, len, value); 230 231 return 0; 232 } 233 234 static int add_man_viewer_info(const char *var, const char *value) 235 { 236 const char *name = var + 4; 237 const char *subkey = strrchr(name, '.'); 238 239 if (!subkey) 240 return error("Config with no key for man viewer: %s", name); 241 242 if (!strcmp(subkey, ".path")) { 243 if (!value) 244 return config_error_nonbool(var); 245 return add_man_viewer_path(name, subkey - name, value); 246 } 247 if (!strcmp(subkey, ".cmd")) { 248 if (!value) 249 return config_error_nonbool(var); 250 return add_man_viewer_cmd(name, subkey - name, value); 251 } 252 253 warning("'%s': unsupported man viewer sub key.", subkey); 254 return 0; 255 } 256 257 static int perf_help_config(const char *var, const char *value, void *cb) 258 { 259 if (!strcmp(var, "help.format")) { 260 if (!value) 261 return config_error_nonbool(var); 262 help_format = parse_help_format(value); 263 return 0; 264 } 265 if (!strcmp(var, "man.viewer")) { 266 if (!value) 267 return config_error_nonbool(var); 268 add_man_viewer(value); 269 return 0; 270 } 271 if (!prefixcmp(var, "man.")) 272 return add_man_viewer_info(var, value); 273 274 return perf_default_config(var, value, cb); 275 } 276 277 static struct cmdnames main_cmds, other_cmds; 278 279 void list_common_cmds_help(void) 280 { 281 unsigned int i, longest = 0; 282 283 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) { 284 if (longest < strlen(common_cmds[i].name)) 285 longest = strlen(common_cmds[i].name); 286 } 287 288 puts(" The most commonly used perf commands are:"); 289 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) { 290 printf(" %s ", common_cmds[i].name); 291 mput_char(' ', longest - strlen(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 if (is_perf_command(perf_cmd)) 319 return prepend("perf-", perf_cmd); 320 else 321 return prepend("perf-", perf_cmd); 322 } 323 324 static void setup_man_path(void) 325 { 326 struct strbuf new_path = STRBUF_INIT; 327 const char *old_path = getenv("MANPATH"); 328 329 /* We should always put ':' after our path. If there is no 330 * old_path, the ':' at the end will let 'man' to try 331 * system-wide paths after ours to find the manual page. If 332 * there is old_path, we need ':' as delimiter. */ 333 strbuf_addstr(&new_path, system_path(PERF_MAN_PATH)); 334 strbuf_addch(&new_path, ':'); 335 if (old_path) 336 strbuf_addstr(&new_path, old_path); 337 338 setenv("MANPATH", new_path.buf, 1); 339 340 strbuf_release(&new_path); 341 } 342 343 static void exec_viewer(const char *name, const char *page) 344 { 345 const char *info = get_man_viewer_info(name); 346 347 if (!strcasecmp(name, "man")) 348 exec_man_man(info, page); 349 else if (!strcasecmp(name, "woman")) 350 exec_woman_emacs(info, page); 351 else if (!strcasecmp(name, "konqueror")) 352 exec_man_konqueror(info, page); 353 else if (info) 354 exec_man_cmd(info, page); 355 else 356 warning("'%s': unknown man viewer.", name); 357 } 358 359 static void show_man_page(const char *perf_cmd) 360 { 361 struct man_viewer_list *viewer; 362 const char *page = cmd_to_page(perf_cmd); 363 const char *fallback = getenv("PERF_MAN_VIEWER"); 364 365 setup_man_path(); 366 for (viewer = man_viewer_list; viewer; viewer = viewer->next) 367 { 368 exec_viewer(viewer->name, page); /* will return when unable */ 369 } 370 if (fallback) 371 exec_viewer(fallback, page); 372 exec_viewer("man", page); 373 die("no man viewer handled the request"); 374 } 375 376 static void show_info_page(const char *perf_cmd) 377 { 378 const char *page = cmd_to_page(perf_cmd); 379 setenv("INFOPATH", system_path(PERF_INFO_PATH), 1); 380 execlp("info", "info", "perfman", page, NULL); 381 } 382 383 static void 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 die("'%s': not a documentation directory.", html_path); 392 393 strbuf_init(page_path, 0); 394 strbuf_addf(page_path, "%s/%s.html", html_path, page); 395 } 396 397 /* 398 * If open_html is not defined in a platform-specific way (see for 399 * example compat/mingw.h), we use the script web--browse to display 400 * HTML. 401 */ 402 #ifndef open_html 403 static void open_html(const char *path) 404 { 405 execl_perf_cmd("web--browse", "-c", "help.browser", path, NULL); 406 } 407 #endif 408 409 static void show_html_page(const char *perf_cmd) 410 { 411 const char *page = cmd_to_page(perf_cmd); 412 struct strbuf page_path; /* it leaks but we exec bellow */ 413 414 get_html_page_path(&page_path, page); 415 416 open_html(page_path.buf); 417 } 418 419 int cmd_help(int argc, const char **argv, const char *prefix __used) 420 { 421 const char *alias; 422 423 load_command_list("perf-", &main_cmds, &other_cmds); 424 425 perf_config(perf_help_config, NULL); 426 427 argc = parse_options(argc, argv, builtin_help_options, 428 builtin_help_usage, 0); 429 430 if (show_all) { 431 printf("\n usage: %s\n\n", perf_usage_string); 432 list_commands("perf commands", &main_cmds, &other_cmds); 433 printf(" %s\n\n", perf_more_info_string); 434 return 0; 435 } 436 437 if (!argv[0]) { 438 printf("\n usage: %s\n\n", perf_usage_string); 439 list_common_cmds_help(); 440 printf("\n %s\n\n", perf_more_info_string); 441 return 0; 442 } 443 444 alias = alias_lookup(argv[0]); 445 if (alias && !is_perf_command(argv[0])) { 446 printf("`perf %s' is aliased to `%s'\n", argv[0], alias); 447 return 0; 448 } 449 450 switch (help_format) { 451 case HELP_FORMAT_MAN: 452 show_man_page(argv[0]); 453 break; 454 case HELP_FORMAT_INFO: 455 show_info_page(argv[0]); 456 break; 457 case HELP_FORMAT_WEB: 458 show_html_page(argv[0]); 459 default: 460 break; 461 } 462 463 return 0; 464 } 465