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 bool show_all = false;
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_UINT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
37 OPT_SET_UINT('w', "web", &help_format, "show manual in web browser",
38 HELP_FORMAT_WEB),
39 OPT_SET_UINT('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
parse_help_format(const char * format)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
get_man_viewer_info(const char * name)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
check_emacsclient_version(void)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
exec_woman_emacs(const char * path,const char * page)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
exec_man_konqueror(const char * path,const char * page)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
exec_man_man(const char * path,const char * page)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
exec_man_cmd(const char * cmd,const char * page)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
add_man_viewer(const char * name)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
supported_man_viewer(const char * name,size_t len)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
do_add_man_viewer_info(const char * name,size_t len,const char * value)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
add_man_viewer_path(const char * name,size_t len,const char * value)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
add_man_viewer_cmd(const char * name,size_t len,const char * value)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
add_man_viewer_info(const char * var,const char * value)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
perf_help_config(const char * var,const char * value,void * cb)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
list_common_cmds_help(void)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 ", longest, common_cmds[i].name);
290 puts(common_cmds[i].help);
291 }
292 }
293
is_perf_command(const char * s)294 static int is_perf_command(const char *s)
295 {
296 return is_in_cmdlist(&main_cmds, s) ||
297 is_in_cmdlist(&other_cmds, s);
298 }
299
prepend(const char * prefix,const char * cmd)300 static const char *prepend(const char *prefix, const char *cmd)
301 {
302 size_t pre_len = strlen(prefix);
303 size_t cmd_len = strlen(cmd);
304 char *p = malloc(pre_len + cmd_len + 1);
305 memcpy(p, prefix, pre_len);
306 strcpy(p + pre_len, cmd);
307 return p;
308 }
309
cmd_to_page(const char * perf_cmd)310 static const char *cmd_to_page(const char *perf_cmd)
311 {
312 if (!perf_cmd)
313 return "perf";
314 else if (!prefixcmp(perf_cmd, "perf"))
315 return perf_cmd;
316 else
317 return prepend("perf-", perf_cmd);
318 }
319
setup_man_path(void)320 static void setup_man_path(void)
321 {
322 struct strbuf new_path = STRBUF_INIT;
323 const char *old_path = getenv("MANPATH");
324
325 /* We should always put ':' after our path. If there is no
326 * old_path, the ':' at the end will let 'man' to try
327 * system-wide paths after ours to find the manual page. If
328 * there is old_path, we need ':' as delimiter. */
329 strbuf_addstr(&new_path, system_path(PERF_MAN_PATH));
330 strbuf_addch(&new_path, ':');
331 if (old_path)
332 strbuf_addstr(&new_path, old_path);
333
334 setenv("MANPATH", new_path.buf, 1);
335
336 strbuf_release(&new_path);
337 }
338
exec_viewer(const char * name,const char * page)339 static void exec_viewer(const char *name, const char *page)
340 {
341 const char *info = get_man_viewer_info(name);
342
343 if (!strcasecmp(name, "man"))
344 exec_man_man(info, page);
345 else if (!strcasecmp(name, "woman"))
346 exec_woman_emacs(info, page);
347 else if (!strcasecmp(name, "konqueror"))
348 exec_man_konqueror(info, page);
349 else if (info)
350 exec_man_cmd(info, page);
351 else
352 warning("'%s': unknown man viewer.", name);
353 }
354
show_man_page(const char * perf_cmd)355 static void show_man_page(const char *perf_cmd)
356 {
357 struct man_viewer_list *viewer;
358 const char *page = cmd_to_page(perf_cmd);
359 const char *fallback = getenv("PERF_MAN_VIEWER");
360
361 setup_man_path();
362 for (viewer = man_viewer_list; viewer; viewer = viewer->next)
363 exec_viewer(viewer->name, page); /* will return when unable */
364
365 if (fallback)
366 exec_viewer(fallback, page);
367 exec_viewer("man", page);
368 die("no man viewer handled the request");
369 }
370
show_info_page(const char * perf_cmd)371 static void show_info_page(const char *perf_cmd)
372 {
373 const char *page = cmd_to_page(perf_cmd);
374 setenv("INFOPATH", system_path(PERF_INFO_PATH), 1);
375 execlp("info", "info", "perfman", page, NULL);
376 }
377
get_html_page_path(struct strbuf * page_path,const char * page)378 static void get_html_page_path(struct strbuf *page_path, const char *page)
379 {
380 struct stat st;
381 const char *html_path = system_path(PERF_HTML_PATH);
382
383 /* Check that we have a perf documentation directory. */
384 if (stat(mkpath("%s/perf.html", html_path), &st)
385 || !S_ISREG(st.st_mode))
386 die("'%s': not a documentation directory.", html_path);
387
388 strbuf_init(page_path, 0);
389 strbuf_addf(page_path, "%s/%s.html", html_path, page);
390 }
391
392 /*
393 * If open_html is not defined in a platform-specific way (see for
394 * example compat/mingw.h), we use the script web--browse to display
395 * HTML.
396 */
397 #ifndef open_html
open_html(const char * path)398 static void open_html(const char *path)
399 {
400 execl_perf_cmd("web--browse", "-c", "help.browser", path, NULL);
401 }
402 #endif
403
show_html_page(const char * perf_cmd)404 static void show_html_page(const char *perf_cmd)
405 {
406 const char *page = cmd_to_page(perf_cmd);
407 struct strbuf page_path; /* it leaks but we exec bellow */
408
409 get_html_page_path(&page_path, page);
410
411 open_html(page_path.buf);
412 }
413
cmd_help(int argc,const char ** argv,const char * prefix __used)414 int cmd_help(int argc, const char **argv, const char *prefix __used)
415 {
416 const char *alias;
417
418 load_command_list("perf-", &main_cmds, &other_cmds);
419
420 perf_config(perf_help_config, NULL);
421
422 argc = parse_options(argc, argv, builtin_help_options,
423 builtin_help_usage, 0);
424
425 if (show_all) {
426 printf("\n usage: %s\n\n", perf_usage_string);
427 list_commands("perf commands", &main_cmds, &other_cmds);
428 printf(" %s\n\n", perf_more_info_string);
429 return 0;
430 }
431
432 if (!argv[0]) {
433 printf("\n usage: %s\n\n", perf_usage_string);
434 list_common_cmds_help();
435 printf("\n %s\n\n", perf_more_info_string);
436 return 0;
437 }
438
439 alias = alias_lookup(argv[0]);
440 if (alias && !is_perf_command(argv[0])) {
441 printf("`perf %s' is aliased to `%s'\n", argv[0], alias);
442 return 0;
443 }
444
445 switch (help_format) {
446 case HELP_FORMAT_MAN:
447 show_man_page(argv[0]);
448 break;
449 case HELP_FORMAT_INFO:
450 show_info_page(argv[0]);
451 break;
452 case HELP_FORMAT_WEB:
453 show_html_page(argv[0]);
454 default:
455 break;
456 }
457
458 return 0;
459 }
460