[deliverable/linux.git] / tools / perf / builtin-help.c

/*
 * builtin-help.c
 *
 * Builtin help command
 */
#include "perf.h"
#include "util/cache.h"
#include "builtin.h"
#include <subcmd/exec-cmd.h>
#include "common-cmds.h"
#include <subcmd/parse-options.h>
#include <subcmd/run-command.h>
#include <subcmd/help.h>
#include "util/debug.h"

static struct man_viewer_list {
	struct man_viewer_list *next;
	char name[FLEX_ARRAY];
} *man_viewer_list;

static struct man_viewer_info_list {
	struct man_viewer_info_list *next;
	const char *info;
	char name[FLEX_ARRAY];
} *man_viewer_info_list;

enum help_format {
	HELP_FORMAT_NONE,
	HELP_FORMAT_MAN,
	HELP_FORMAT_INFO,
	HELP_FORMAT_WEB,
};

static enum help_format parse_help_format(const char *format)
{
	if (!strcmp(format, "man"))
		return HELP_FORMAT_MAN;
	if (!strcmp(format, "info"))
		return HELP_FORMAT_INFO;
	if (!strcmp(format, "web") || !strcmp(format, "html"))
		return HELP_FORMAT_WEB;

	pr_err("unrecognized help format '%s'", format);
	return HELP_FORMAT_NONE;
}

static const char *get_man_viewer_info(const char *name)
{
	struct man_viewer_info_list *viewer;

	for (viewer = man_viewer_info_list; viewer; viewer = viewer->next) {
		if (!strcasecmp(name, viewer->name))
			return viewer->info;
	}
	return NULL;
}

static int check_emacsclient_version(void)
{
	struct strbuf buffer = STRBUF_INIT;
	struct child_process ec_process;
	const char *argv_ec[] = { "emacsclient", "--version", NULL };
	int version;

	/* emacsclient prints its version number on stderr */
	memset(&ec_process, 0, sizeof(ec_process));
	ec_process.argv = argv_ec;
	ec_process.err = -1;
	ec_process.stdout_to_stderr = 1;
	if (start_command(&ec_process)) {
		fprintf(stderr, "Failed to start emacsclient.\n");
		return -1;
	}
	strbuf_read(&buffer, ec_process.err, 20);
	close(ec_process.err);

	/*
	 * Don't bother checking return value, because "emacsclient --version"
	 * seems to always exits with code 1.
	 */
	finish_command(&ec_process);

	if (prefixcmp(buffer.buf, "emacsclient")) {
		fprintf(stderr, "Failed to parse emacsclient version.\n");
		strbuf_release(&buffer);
		return -1;
	}

	strbuf_remove(&buffer, 0, strlen("emacsclient"));
	version = atoi(buffer.buf);

	if (version < 22) {
		fprintf(stderr,
			"emacsclient version '%d' too old (< 22).\n",
			version);
		strbuf_release(&buffer);
		return -1;
	}

	strbuf_release(&buffer);
	return 0;
}

static void exec_woman_emacs(const char *path, const char *page)
{
	char sbuf[STRERR_BUFSIZE];

	if (!check_emacsclient_version()) {
		/* This works only with emacsclient version >= 22. */
		struct strbuf man_page = STRBUF_INIT;

		if (!path)
			path = "emacsclient";
		strbuf_addf(&man_page, "(woman \"%s\")", page);
		execlp(path, "emacsclient", "-e", man_page.buf, NULL);
		warning("failed to exec '%s': %s", path,
			strerror_r(errno, sbuf, sizeof(sbuf)));
	}
}

static void exec_man_konqueror(const char *path, const char *page)
{
	const char *display = getenv("DISPLAY");

	if (display && *display) {
		struct strbuf man_page = STRBUF_INIT;
		const char *filename = "kfmclient";
		char sbuf[STRERR_BUFSIZE];

		/* It's simpler to launch konqueror using kfmclient. */
		if (path) {
			const char *file = strrchr(path, '/');
			if (file && !strcmp(file + 1, "konqueror")) {
				char *new = strdup(path);
				char *dest = strrchr(new, '/');

				/* strlen("konqueror") == strlen("kfmclient") */
				strcpy(dest + 1, "kfmclient");
				path = new;
			}
			if (file)
				filename = file;
		} else
			path = "kfmclient";
		strbuf_addf(&man_page, "man:%s(1)", page);
		execlp(path, filename, "newTab", man_page.buf, NULL);
		warning("failed to exec '%s': %s", path,
			strerror_r(errno, sbuf, sizeof(sbuf)));
	}
}

static void exec_man_man(const char *path, const char *page)
{
	char sbuf[STRERR_BUFSIZE];

	if (!path)
		path = "man";
	execlp(path, "man", page, NULL);
	warning("failed to exec '%s': %s", path,
		strerror_r(errno, sbuf, sizeof(sbuf)));
}

static void exec_man_cmd(const char *cmd, const char *page)
{
	struct strbuf shell_cmd = STRBUF_INIT;
	char sbuf[STRERR_BUFSIZE];

	strbuf_addf(&shell_cmd, "%s %s", cmd, page);
	execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
	warning("failed to exec '%s': %s", cmd,
		strerror_r(errno, sbuf, sizeof(sbuf)));
}

static void add_man_viewer(const char *name)
{
	struct man_viewer_list **p = &man_viewer_list;
	size_t len = strlen(name);

	while (*p)
		p = &((*p)->next);
	*p = zalloc(sizeof(**p) + len + 1);
	strncpy((*p)->name, name, len);
}

static int supported_man_viewer(const char *name, size_t len)
{
	return (!strncasecmp("man", name, len) ||
		!strncasecmp("woman", name, len) ||
		!strncasecmp("konqueror", name, len));
}

static void do_add_man_viewer_info(const char *name,
				   size_t len,
				   const char *value)
{
	struct man_viewer_info_list *new = zalloc(sizeof(*new) + len + 1);

	strncpy(new->name, name, len);
	new->info = strdup(value);
	new->next = man_viewer_info_list;
	man_viewer_info_list = new;
}

static int add_man_viewer_path(const char *name,
			       size_t len,
			       const char *value)
{
	if (supported_man_viewer(name, len))
		do_add_man_viewer_info(name, len, value);
	else
		warning("'%s': path for unsupported man viewer.\n"
			"Please consider using 'man.<tool>.cmd' instead.",
			name);

	return 0;
}

static int add_man_viewer_cmd(const char *name,
			      size_t len,
			      const char *value)
{
	if (supported_man_viewer(name, len))
		warning("'%s': cmd for supported man viewer.\n"
			"Please consider using 'man.<tool>.path' instead.",
			name);
	else
		do_add_man_viewer_info(name, len, value);

	return 0;
}

static int add_man_viewer_info(const char *var, const char *value)
{
	const char *name = var + 4;
	const char *subkey = strrchr(name, '.');

	if (!subkey)
		return error("Config with no key for man viewer: %s", name);

	if (!strcmp(subkey, ".path")) {
		if (!value)
			return config_error_nonbool(var);
		return add_man_viewer_path(name, subkey - name, value);
	}
	if (!strcmp(subkey, ".cmd")) {
		if (!value)
			return config_error_nonbool(var);
		return add_man_viewer_cmd(name, subkey - name, value);
	}

	warning("'%s': unsupported man viewer sub key.", subkey);
	return 0;
}

static int perf_help_config(const char *var, const char *value, void *cb)
{
	enum help_format *help_formatp = cb;

	if (!strcmp(var, "help.format")) {
		if (!value)
			return config_error_nonbool(var);
		*help_formatp = parse_help_format(value);
		if (*help_formatp == HELP_FORMAT_NONE)
			return -1;
		return 0;
	}
	if (!strcmp(var, "man.viewer")) {
		if (!value)
			return config_error_nonbool(var);
		add_man_viewer(value);
		return 0;
	}
	if (!prefixcmp(var, "man."))
		return add_man_viewer_info(var, value);

	return perf_default_config(var, value, cb);
}

static struct cmdnames main_cmds, other_cmds;

void list_common_cmds_help(void)
{
	unsigned int i, longest = 0;

	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
		if (longest < strlen(common_cmds[i].name))
			longest = strlen(common_cmds[i].name);
	}

	puts(" The most commonly used perf commands are:");
	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
		printf("   %-*s   ", longest, common_cmds[i].name);
		puts(common_cmds[i].help);
	}
}

static int is_perf_command(const char *s)
{
	return is_in_cmdlist(&main_cmds, s) ||
		is_in_cmdlist(&other_cmds, s);
}

static const char *prepend(const char *prefix, const char *cmd)
{
	size_t pre_len = strlen(prefix);
	size_t cmd_len = strlen(cmd);
	char *p = malloc(pre_len + cmd_len + 1);
	memcpy(p, prefix, pre_len);
	strcpy(p + pre_len, cmd);
	return p;
}

static const char *cmd_to_page(const char *perf_cmd)
{
	if (!perf_cmd)
		return "perf";
	else if (!prefixcmp(perf_cmd, "perf"))
		return perf_cmd;
	else
		return prepend("perf-", perf_cmd);
}

static void setup_man_path(void)
{
	struct strbuf new_path = STRBUF_INIT;
	const char *old_path = getenv("MANPATH");

	/* We should always put ':' after our path. If there is no
	 * old_path, the ':' at the end will let 'man' to try
	 * system-wide paths after ours to find the manual page. If
	 * there is old_path, we need ':' as delimiter. */
	strbuf_addstr(&new_path, system_path(PERF_MAN_PATH));
	strbuf_addch(&new_path, ':');
	if (old_path)
		strbuf_addstr(&new_path, old_path);

	setenv("MANPATH", new_path.buf, 1);

	strbuf_release(&new_path);
}

static void exec_viewer(const char *name, const char *page)
{
	const char *info = get_man_viewer_info(name);

	if (!strcasecmp(name, "man"))
		exec_man_man(info, page);
	else if (!strcasecmp(name, "woman"))
		exec_woman_emacs(info, page);
	else if (!strcasecmp(name, "konqueror"))
		exec_man_konqueror(info, page);
	else if (info)
		exec_man_cmd(info, page);
	else
		warning("'%s': unknown man viewer.", name);
}

static int show_man_page(const char *perf_cmd)
{
	struct man_viewer_list *viewer;
	const char *page = cmd_to_page(perf_cmd);
	const char *fallback = getenv("PERF_MAN_VIEWER");

	setup_man_path();
	for (viewer = man_viewer_list; viewer; viewer = viewer->next)
		exec_viewer(viewer->name, page); /* will return when unable */

	if (fallback)
		exec_viewer(fallback, page);
	exec_viewer("man", page);

	pr_err("no man viewer handled the request");
	return -1;
}

static int show_info_page(const char *perf_cmd)
{
	const char *page = cmd_to_page(perf_cmd);
	setenv("INFOPATH", system_path(PERF_INFO_PATH), 1);
	execlp("info", "info", "perfman", page, NULL);
	return -1;
}

static int get_html_page_path(struct strbuf *page_path, const char *page)
{
	struct stat st;
	const char *html_path = system_path(PERF_HTML_PATH);

	/* Check that we have a perf documentation directory. */
	if (stat(mkpath("%s/perf.html", html_path), &st)
	    || !S_ISREG(st.st_mode)) {
		pr_err("'%s': not a documentation directory.", html_path);
		return -1;
	}

	strbuf_init(page_path, 0);
	strbuf_addf(page_path, "%s/%s.html", html_path, page);

	return 0;
}

/*
 * If open_html is not defined in a platform-specific way (see for
 * example compat/mingw.h), we use the script web--browse to display
 * HTML.
 */
#ifndef open_html
static void open_html(const char *path)
{
	execl_cmd("web--browse", "-c", "help.browser", path, NULL);
}
#endif

static int show_html_page(const char *perf_cmd)
{
	const char *page = cmd_to_page(perf_cmd);
	struct strbuf page_path; /* it leaks but we exec bellow */

	if (get_html_page_path(&page_path, page) != 0)
		return -1;

	open_html(page_path.buf);

	return 0;
}

int cmd_help(int argc, const char **argv, const char *prefix __maybe_unused)
{
	bool show_all = false;
	enum help_format help_format = HELP_FORMAT_MAN;
	struct option builtin_help_options[] = {
	OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
	OPT_SET_UINT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
	OPT_SET_UINT('w', "web", &help_format, "show manual in web browser",
			HELP_FORMAT_WEB),
	OPT_SET_UINT('i', "info", &help_format, "show info page",
			HELP_FORMAT_INFO),
	OPT_END(),
	};
	const char * const builtin_help_subcommands[] = {
		"buildid-cache", "buildid-list", "diff", "evlist", "help", "list",
		"record", "report", "bench", "stat", "timechart", "top", "annotate",
		"script", "sched", "kmem", "lock", "kvm", "test", "inject", "mem", "data",
#ifdef HAVE_LIBELF_SUPPORT
		"probe",
#endif
#ifdef HAVE_LIBAUDIT_SUPPORT
		"trace",
#endif
	NULL };
	const char *builtin_help_usage[] = {
		"perf help [--all] [--man|--web|--info] [command]",
		NULL
	};
	const char *alias;
	int rc = 0;

	load_command_list("perf-", &main_cmds, &other_cmds);

	perf_config(perf_help_config, &help_format);

	argc = parse_options_subcommand(argc, argv, builtin_help_options,
			builtin_help_subcommands, builtin_help_usage, 0);

	if (show_all) {
		printf("\n Usage: %s\n\n", perf_usage_string);
		list_commands("perf commands", &main_cmds, &other_cmds);
		printf(" %s\n\n", perf_more_info_string);
		return 0;
	}

	if (!argv[0]) {
		printf("\n usage: %s\n\n", perf_usage_string);
		list_common_cmds_help();
		printf("\n %s\n\n", perf_more_info_string);
		return 0;
	}

	alias = alias_lookup(argv[0]);
	if (alias && !is_perf_command(argv[0])) {
		printf("`perf %s' is aliased to `%s'\n", argv[0], alias);
		return 0;
	}

	switch (help_format) {
	case HELP_FORMAT_MAN:
		rc = show_man_page(argv[0]);
		break;
	case HELP_FORMAT_INFO:
		rc = show_info_page(argv[0]);
		break;
	case HELP_FORMAT_WEB:
		rc = show_html_page(argv[0]);
		break;
	case HELP_FORMAT_NONE:
		/* fall-through */
	default:
		rc = -1;
		break;
	}

	return rc;
}
Commit	Line	Data
07800601 IM	1	/*
	2	* builtin-help.c
	3	*
	4	* Builtin help command
	5	*/
f37a291c	6	#include "perf.h"
148be2c1	7	#include "util/cache.h"
07800601	8	#include "builtin.h"
4b6ab94e	9	#include <subcmd/exec-cmd.h>
07800601	10	#include "common-cmds.h"
4b6ab94e JP	11	#include <subcmd/parse-options.h>
	12	#include <subcmd/run-command.h>
	13	#include <subcmd/help.h>
84f5d36f	14	#include "util/debug.h"
07800601 IM	15
	16	static struct man_viewer_list {
	17	struct man_viewer_list *next;
	18	char name[FLEX_ARRAY];
	19	} *man_viewer_list;
	20
	21	static struct man_viewer_info_list {
	22	struct man_viewer_info_list *next;
	23	const char *info;
	24	char name[FLEX_ARRAY];
	25	} *man_viewer_info_list;
	26
	27	enum help_format {
cc584821	28	HELP_FORMAT_NONE,
07800601 IM	29	HELP_FORMAT_MAN,
	30	HELP_FORMAT_INFO,
	31	HELP_FORMAT_WEB,
	32	};
	33
07800601 IM	34	static enum help_format parse_help_format(const char *format)
	35	{
	36	if (!strcmp(format, "man"))
	37	return HELP_FORMAT_MAN;
	38	if (!strcmp(format, "info"))
	39	return HELP_FORMAT_INFO;
	40	if (!strcmp(format, "web") \|\| !strcmp(format, "html"))
	41	return HELP_FORMAT_WEB;
cc584821 DA	42
	43	pr_err("unrecognized help format '%s'", format);
	44	return HELP_FORMAT_NONE;
07800601 IM	45	}
	46
	47	static const char get_man_viewer_info(const char name)
	48	{
	49	struct man_viewer_info_list *viewer;
	50
c1e53017	51	for (viewer = man_viewer_info_list; viewer; viewer = viewer->next) {
07800601 IM	52	if (!strcasecmp(name, viewer->name))
	53	return viewer->info;
	54	}
	55	return NULL;
	56	}
	57
	58	static int check_emacsclient_version(void)
	59	{
	60	struct strbuf buffer = STRBUF_INIT;
	61	struct child_process ec_process;
	62	const char *argv_ec[] = { "emacsclient", "--version", NULL };
	63	int version;
	64
	65	/* emacsclient prints its version number on stderr */
	66	memset(&ec_process, 0, sizeof(ec_process));
	67	ec_process.argv = argv_ec;
	68	ec_process.err = -1;
	69	ec_process.stdout_to_stderr = 1;
	70	if (start_command(&ec_process)) {
	71	fprintf(stderr, "Failed to start emacsclient.\n");
	72	return -1;
	73	}
	74	strbuf_read(&buffer, ec_process.err, 20);
	75	close(ec_process.err);
	76
	77	/*
	78	* Don't bother checking return value, because "emacsclient --version"
	79	* seems to always exits with code 1.
	80	*/
	81	finish_command(&ec_process);
	82
	83	if (prefixcmp(buffer.buf, "emacsclient")) {
	84	fprintf(stderr, "Failed to parse emacsclient version.\n");
	85	strbuf_release(&buffer);
	86	return -1;
	87	}
	88
	89	strbuf_remove(&buffer, 0, strlen("emacsclient"));
	90	version = atoi(buffer.buf);
	91
	92	if (version < 22) {
	93	fprintf(stderr,
	94	"emacsclient version '%d' too old (< 22).\n",
	95	version);
	96	strbuf_release(&buffer);
	97	return -1;
	98	}
	99
	100	strbuf_release(&buffer);
	101	return 0;
	102	}
	103
c1e53017	104	static void exec_woman_emacs(const char path, const char page)
07800601	105	{
ede395d2 MH	106	char sbuf[STRERR_BUFSIZE];
ede395d2 MH	107
07800601 IM	108	if (!check_emacsclient_version()) {
	109	/* This works only with emacsclient version >= 22. */
	110	struct strbuf man_page = STRBUF_INIT;
	111
	112	if (!path)
	113	path = "emacsclient";
	114	strbuf_addf(&man_page, "(woman \"%s\")", page);
	115	execlp(path, "emacsclient", "-e", man_page.buf, NULL);
ede395d2 MH	116	warning("failed to exec '%s': %s", path,
ede395d2 MH	117	strerror_r(errno, sbuf, sizeof(sbuf)));
07800601 IM	118	}
	119	}
	120
c1e53017	121	static void exec_man_konqueror(const char path, const char page)
07800601 IM	122	{
07800601 IM	123	const char *display = getenv("DISPLAY");
ede395d2	124
07800601 IM	125	if (display && *display) {
	126	struct strbuf man_page = STRBUF_INIT;
	127	const char *filename = "kfmclient";
ede395d2	128	char sbuf[STRERR_BUFSIZE];
07800601 IM	129
	130	/* It's simpler to launch konqueror using kfmclient. */
	131	if (path) {
	132	const char *file = strrchr(path, '/');
	133	if (file && !strcmp(file + 1, "konqueror")) {
	134	char *new = strdup(path);
	135	char *dest = strrchr(new, '/');
	136
	137	/* strlen("konqueror") == strlen("kfmclient") */
	138	strcpy(dest + 1, "kfmclient");
	139	path = new;
	140	}
	141	if (file)
	142	filename = file;
	143	} else
	144	path = "kfmclient";
	145	strbuf_addf(&man_page, "man:%s(1)", page);
	146	execlp(path, filename, "newTab", man_page.buf, NULL);
ede395d2 MH	147	warning("failed to exec '%s': %s", path,
ede395d2 MH	148	strerror_r(errno, sbuf, sizeof(sbuf)));
07800601 IM	149	}
	150	}
	151
c1e53017	152	static void exec_man_man(const char path, const char page)
07800601	153	{
ede395d2 MH	154	char sbuf[STRERR_BUFSIZE];
ede395d2 MH	155
07800601 IM	156	if (!path)
	157	path = "man";
	158	execlp(path, "man", page, NULL);
ede395d2 MH	159	warning("failed to exec '%s': %s", path,
ede395d2 MH	160	strerror_r(errno, sbuf, sizeof(sbuf)));
07800601 IM	161	}
	162
	163	static void exec_man_cmd(const char cmd, const char page)
	164	{
	165	struct strbuf shell_cmd = STRBUF_INIT;
ede395d2 MH	166	char sbuf[STRERR_BUFSIZE];
ede395d2 MH	167
07800601 IM	168	strbuf_addf(&shell_cmd, "%s %s", cmd, page);
07800601 IM	169	execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
ede395d2 MH	170	warning("failed to exec '%s': %s", cmd,
ede395d2 MH	171	strerror_r(errno, sbuf, sizeof(sbuf)));
07800601 IM	172	}
	173
	174	static void add_man_viewer(const char *name)
	175	{
	176	struct man_viewer_list **p = &man_viewer_list;
	177	size_t len = strlen(name);
	178
	179	while (*p)
	180	p = &((*p)->next);
36479484	181	p = zalloc(sizeof(*p) + len + 1);
07800601 IM	182	strncpy((*p)->name, name, len);
	183	}
	184
	185	static int supported_man_viewer(const char *name, size_t len)
	186	{
	187	return (!strncasecmp("man", name, len) \|\|
	188	!strncasecmp("woman", name, len) \|\|
	189	!strncasecmp("konqueror", name, len));
	190	}
	191
	192	static void do_add_man_viewer_info(const char *name,
	193	size_t len,
	194	const char *value)
	195	{
36479484	196	struct man_viewer_info_list new = zalloc(sizeof(new) + len + 1);
07800601 IM	197
	198	strncpy(new->name, name, len);
	199	new->info = strdup(value);
	200	new->next = man_viewer_info_list;
	201	man_viewer_info_list = new;
	202	}
	203
	204	static int add_man_viewer_path(const char *name,
	205	size_t len,
	206	const char *value)
	207	{
	208	if (supported_man_viewer(name, len))
	209	do_add_man_viewer_info(name, len, value);
	210	else
	211	warning("'%s': path for unsupported man viewer.\n"
	212	"Please consider using 'man.<tool>.cmd' instead.",
	213	name);
	214
	215	return 0;
	216	}
	217
	218	static int add_man_viewer_cmd(const char *name,
	219	size_t len,
	220	const char *value)
	221	{
	222	if (supported_man_viewer(name, len))
	223	warning("'%s': cmd for supported man viewer.\n"
	224	"Please consider using 'man.<tool>.path' instead.",
	225	name);
	226	else
	227	do_add_man_viewer_info(name, len, value);
	228
	229	return 0;
	230	}
	231
	232	static int add_man_viewer_info(const char var, const char value)
	233	{
	234	const char *name = var + 4;
	235	const char *subkey = strrchr(name, '.');
	236
	237	if (!subkey)
	238	return error("Config with no key for man viewer: %s", name);
	239
	240	if (!strcmp(subkey, ".path")) {
	241	if (!value)
	242	return config_error_nonbool(var);
	243	return add_man_viewer_path(name, subkey - name, value);
	244	}
	245	if (!strcmp(subkey, ".cmd")) {
	246	if (!value)
	247	return config_error_nonbool(var);
	248	return add_man_viewer_cmd(name, subkey - name, value);
	249	}
	250
	251	warning("'%s': unsupported man viewer sub key.", subkey);
	252	return 0;
	253	}
	254
	255	static int perf_help_config(const char var, const char value, void *cb)
	256	{
2bae1d1b ACM	257	enum help_format *help_formatp = cb;
2bae1d1b ACM	258
07800601 IM	259	if (!strcmp(var, "help.format")) {
	260	if (!value)
	261	return config_error_nonbool(var);
2bae1d1b ACM	262	*help_formatp = parse_help_format(value);
2bae1d1b ACM	263	if (*help_formatp == HELP_FORMAT_NONE)
cc584821	264	return -1;
07800601 IM	265	return 0;
	266	}
	267	if (!strcmp(var, "man.viewer")) {
	268	if (!value)
	269	return config_error_nonbool(var);
	270	add_man_viewer(value);
	271	return 0;
	272	}
	273	if (!prefixcmp(var, "man."))
	274	return add_man_viewer_info(var, value);
	275
	276	return perf_default_config(var, value, cb);
	277	}
	278
	279	static struct cmdnames main_cmds, other_cmds;
	280
	281	void list_common_cmds_help(void)
	282	{
f37a291c	283	unsigned int i, longest = 0;
07800601 IM	284
	285	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
	286	if (longest < strlen(common_cmds[i].name))
	287	longest = strlen(common_cmds[i].name);
	288	}
	289
502fc5c7	290	puts(" The most commonly used perf commands are:");
07800601	291	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
3912f2ab	292	printf(" %-*s ", longest, common_cmds[i].name);
07800601 IM	293	puts(common_cmds[i].help);
	294	}
	295	}
	296
	297	static int is_perf_command(const char *s)
	298	{
	299	return is_in_cmdlist(&main_cmds, s) \|\|
	300	is_in_cmdlist(&other_cmds, s);
	301	}
	302
	303	static const char prepend(const char prefix, const char *cmd)
	304	{
	305	size_t pre_len = strlen(prefix);
	306	size_t cmd_len = strlen(cmd);
	307	char *p = malloc(pre_len + cmd_len + 1);
	308	memcpy(p, prefix, pre_len);
	309	strcpy(p + pre_len, cmd);
	310	return p;
	311	}
	312
	313	static const char cmd_to_page(const char perf_cmd)
	314	{
	315	if (!perf_cmd)
	316	return "perf";
	317	else if (!prefixcmp(perf_cmd, "perf"))
	318	return perf_cmd;
07800601	319	else
c1c2365a	320	return prepend("perf-", perf_cmd);
07800601 IM	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
cc584821	358	static int show_man_page(const char *perf_cmd)
07800601 IM	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)
07800601	366	exec_viewer(viewer->name, page); /* will return when unable */
c1e53017	367
07800601 IM	368	if (fallback)
	369	exec_viewer(fallback, page);
	370	exec_viewer("man", page);
cc584821 DA	371
	372	pr_err("no man viewer handled the request");
	373	return -1;
07800601 IM	374	}
07800601 IM	375
cc584821	376	static int show_info_page(const char *perf_cmd)
07800601 IM	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);
cc584821	381	return -1;
07800601 IM	382	}
07800601 IM	383
cc584821	384	static int get_html_page_path(struct strbuf page_path, const char page)
07800601 IM	385	{
	386	struct stat st;
	387	const char *html_path = system_path(PERF_HTML_PATH);
	388
	389	/* Check that we have a perf documentation directory. */
	390	if (stat(mkpath("%s/perf.html", html_path), &st)
cc584821 DA	391	\|\| !S_ISREG(st.st_mode)) {
	392	pr_err("'%s': not a documentation directory.", html_path);
	393	return -1;
	394	}
07800601 IM	395
	396	strbuf_init(page_path, 0);
	397	strbuf_addf(page_path, "%s/%s.html", html_path, page);
cc584821 DA	398
cc584821 DA	399	return 0;
07800601 IM	400	}
	401
	402	/*
	403	* If open_html is not defined in a platform-specific way (see for
	404	* example compat/mingw.h), we use the script web--browse to display
	405	* HTML.
	406	*/
	407	#ifndef open_html
16f762a2	408	static void open_html(const char *path)
07800601	409	{
46113a54	410	execl_cmd("web--browse", "-c", "help.browser", path, NULL);
07800601 IM	411	}
	412	#endif
	413
cc584821	414	static int show_html_page(const char *perf_cmd)
07800601 IM	415	{
	416	const char *page = cmd_to_page(perf_cmd);
	417	struct strbuf page_path; /* it leaks but we exec bellow */
	418
cc584821 DA	419	if (get_html_page_path(&page_path, page) != 0)
cc584821 DA	420	return -1;
07800601 IM	421
07800601 IM	422	open_html(page_path.buf);
cc584821 DA	423
cc584821 DA	424	return 0;
07800601 IM	425	}
07800601 IM	426
1d037ca1	427	int cmd_help(int argc, const char *argv, const char prefix __maybe_unused)
07800601	428	{
2bae1d1b	429	bool show_all = false;
670ab5d2	430	enum help_format help_format = HELP_FORMAT_MAN;
2bae1d1b ACM	431	struct option builtin_help_options[] = {
	432	OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
	433	OPT_SET_UINT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
	434	OPT_SET_UINT('w', "web", &help_format, "show manual in web browser",
	435	HELP_FORMAT_WEB),
	436	OPT_SET_UINT('i', "info", &help_format, "show info page",
	437	HELP_FORMAT_INFO),
	438	OPT_END(),
	439	};
e24a1108 YS	440	const char * const builtin_help_subcommands[] = {
	441	"buildid-cache", "buildid-list", "diff", "evlist", "help", "list",
	442	"record", "report", "bench", "stat", "timechart", "top", "annotate",
	443	"script", "sched", "kmem", "lock", "kvm", "test", "inject", "mem", "data",
	444	#ifdef HAVE_LIBELF_SUPPORT
	445	"probe",
	446	#endif
	447	#ifdef HAVE_LIBAUDIT_SUPPORT
	448	"trace",
	449	#endif
	450	NULL };
	451	const char *builtin_help_usage[] = {
2bae1d1b ACM	452	"perf help [--all] [--man\|--web\|--info] [command]",
	453	NULL
	454	};
07800601	455	const char *alias;
cc584821	456	int rc = 0;
f37a291c	457
07800601 IM	458	load_command_list("perf-", &main_cmds, &other_cmds);
07800601 IM	459
2bae1d1b	460	perf_config(perf_help_config, &help_format);
07800601	461
e24a1108 YS	462	argc = parse_options_subcommand(argc, argv, builtin_help_options,
e24a1108 YS	463	builtin_help_subcommands, builtin_help_usage, 0);
07800601 IM	464
07800601 IM	465	if (show_all) {
3a134ae9	466	printf("\n Usage: %s\n\n", perf_usage_string);
07800601	467	list_commands("perf commands", &main_cmds, &other_cmds);
502fc5c7	468	printf(" %s\n\n", perf_more_info_string);
07800601 IM	469	return 0;
	470	}
	471
	472	if (!argv[0]) {
502fc5c7	473	printf("\n usage: %s\n\n", perf_usage_string);
07800601	474	list_common_cmds_help();
502fc5c7	475	printf("\n %s\n\n", perf_more_info_string);
07800601 IM	476	return 0;
	477	}
	478
	479	alias = alias_lookup(argv[0]);
	480	if (alias && !is_perf_command(argv[0])) {
	481	printf("`perf %s' is aliased to `%s'\n", argv[0], alias);
	482	return 0;
	483	}
	484
	485	switch (help_format) {
	486	case HELP_FORMAT_MAN:
cc584821	487	rc = show_man_page(argv[0]);
07800601 IM	488	break;
07800601 IM	489	case HELP_FORMAT_INFO:
cc584821	490	rc = show_info_page(argv[0]);
07800601 IM	491	break;
07800601 IM	492	case HELP_FORMAT_WEB:
cc584821 DA	493	rc = show_html_page(argv[0]);
	494	break;
	495	case HELP_FORMAT_NONE:
	496	/* fall-through */
83a0944f	497	default:
cc584821	498	rc = -1;
07800601 IM	499	break;
	500	}
	501
cc584821	502	return rc;
07800601	503	}