Btrfs: fix qgroup rescan to work with skinny metadata
[linux-2.6-microblaze.git] / tools / perf / builtin-help.c
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 }