builtin-script.c

				snprintf(script_path, MAXPATHLEN, "%s/%s",
					 lang_path, script_dirent.d_name);
				read_script_info(desc, script_path);
				free(script_root);
			}
		}
	}

	fprintf(stdout, "List of available trace scripts:\n");
	list_for_each_entry(desc, &script_descs, node) {
		sprintf(first_half, "%s %s", desc->name,
			desc->args ? desc->args : "");
		fprintf(stdout, "  %-36s %s\n", first_half,
			desc->half_liner ? desc->half_liner : "");
	}

	exit(0);
}

/*
 * Some scripts specify the required events in their "xxx-record" file,
 * this function will check if the events in perf.data match those
 * mentioned in the "xxx-record".
 *
 * Fixme: All existing "xxx-record" are all in good formats "-e event ",
 * which is covered well now. And new parsing code should be added to
 * cover the future complexing formats like event groups etc.
 */
static int check_ev_match(char *dir_name, char *scriptname,
			struct perf_session *session)
{
	char filename[MAXPATHLEN], evname[128];
	char line[BUFSIZ], *p;
	struct perf_evsel *pos;
	int match, len;
	FILE *fp;

	sprintf(filename, "%s/bin/%s-record", dir_name, scriptname);

	fp = fopen(filename, "r");
	if (!fp)
		return -1;

	while (fgets(line, sizeof(line), fp)) {
		p = ltrim(line);
		if (*p == '#')
			continue;

		while (strlen(p)) {
			p = strstr(p, "-e");
			if (!p)
				break;

			p += 2;
			p = ltrim(p);
			len = strcspn(p, " \t");
			if (!len)
				break;

			snprintf(evname, len + 1, "%s", p);

			match = 0;
			list_for_each_entry(pos,
					&session->evlist->entries, node) {
				if (!strcmp(perf_evsel__name(pos), evname)) {
					match = 1;
					break;
				}
			}

			if (!match) {
				fclose(fp);
				return -1;
			}
		}
	}

	fclose(fp);
	return 0;
}

/*
 * Return -1 if none is found, otherwise the actual scripts number.
 *
 * Currently the only user of this function is the script browser, which
 * will list all statically runnable scripts, select one, execute it and
 * show the output in a perf browser.
 */
int find_scripts(char **scripts_array, char **scripts_path_array)
{
	struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
	char scripts_path[MAXPATHLEN], lang_path[MAXPATHLEN];
	DIR *scripts_dir, *lang_dir;
	struct perf_session *session;
	char *temp;
	int i = 0;

	session = perf_session__new(input_name, O_RDONLY, 0, false, NULL);
	if (!session)
		return -1;

	snprintf(scripts_path, MAXPATHLEN, "%s/scripts", perf_exec_path());

	scripts_dir = opendir(scripts_path);
	if (!scripts_dir) {
		perf_session__delete(session);
		return -1;
	}

	for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
		snprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
			 lang_dirent.d_name);
#ifdef NO_LIBPERL
		if (strstr(lang_path, "perl"))
			continue;
#endif
#ifdef NO_LIBPYTHON
		if (strstr(lang_path, "python"))
			continue;
#endif

		lang_dir = opendir(lang_path);
		if (!lang_dir)
			continue;

		for_each_script(lang_path, lang_dir, script_dirent, script_next) {
			/* Skip those real time scripts: xxxtop.p[yl] */
			if (strstr(script_dirent.d_name, "top."))
				continue;
			sprintf(scripts_path_array[i], "%s/%s", lang_path,
				script_dirent.d_name);
			temp = strchr(script_dirent.d_name, '.');
			snprintf(scripts_array[i],
				(temp - script_dirent.d_name) + 1,
				"%s", script_dirent.d_name);

			if (check_ev_match(lang_path,
					scripts_array[i], session))
				continue;

			i++;
		}
		closedir(lang_dir);
	}

	closedir(scripts_dir);
	perf_session__delete(session);
	return i;
}

static char *get_script_path(const char *script_root, const char *suffix)
{
	struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
	char scripts_path[MAXPATHLEN];
	char script_path[MAXPATHLEN];
	DIR *scripts_dir, *lang_dir;
	char lang_path[MAXPATHLEN];
	char *__script_root;

	snprintf(scripts_path, MAXPATHLEN, "%s/scripts", perf_exec_path());

	scripts_dir = opendir(scripts_path);
	if (!scripts_dir)
		return NULL;

	for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
		snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
			 lang_dirent.d_name);
		lang_dir = opendir(lang_path);
		if (!lang_dir)
			continue;

		for_each_script(lang_path, lang_dir, script_dirent, script_next) {
			__script_root = get_script_root(&script_dirent, suffix);
			if (__script_root && !strcmp(script_root, __script_root)) {
				free(__script_root);
				closedir(lang_dir);
				closedir(scripts_dir);
				snprintf(script_path, MAXPATHLEN, "%s/%s",
					 lang_path, script_dirent.d_name);
				return strdup(script_path);
			}
			free(__script_root);
		}
		closedir(lang_dir);
	}
	closedir(scripts_dir);

	return NULL;
}

static bool is_top_script(const char *script_path)
{
	return ends_with(script_path, "top") == NULL ? false : true;
}

static int has_required_arg(char *script_path)
{
	struct script_desc *desc;
	int n_args = 0;
	char *p;

	desc = script_desc__new(NULL);

	if (read_script_info(desc, script_path))
		goto out;

	if (!desc->args)
		goto out;

	for (p = desc->args; *p; p++)
		if (*p == '<')
			n_args++;
out:
	script_desc__delete(desc);

	return n_args;
}

static int have_cmd(int argc, const char **argv)
{
	char **__argv = malloc(sizeof(const char *) * argc);

	if (!__argv) {
		pr_err("malloc failed\n");
		return -1;
	}

	memcpy(__argv, argv, sizeof(const char *) * argc);
	argc = parse_options(argc, (const char **)__argv, record_options,
			     NULL, PARSE_OPT_STOP_AT_NON_OPTION);
	free(__argv);

	system_wide = (argc == 0);

	return 0;
}

int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
{
	bool show_full_info = false;
	char *rec_script_path = NULL;
	char *rep_script_path = NULL;
	struct perf_session *session;
	char *script_path = NULL;
	const char **__argv;
	int i, j, err;
	const struct option options[] = {
	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
		    "dump raw trace in ASCII"),
	OPT_INCR('v', "verbose", &verbose,
		 "be more verbose (show symbol address, etc)"),
	OPT_BOOLEAN('L', "Latency", &latency_format,
		    "show latency attributes (irqs/preemption disabled, etc)"),
	OPT_CALLBACK_NOOPT('l', "list", NULL, NULL, "list available scripts",
			   list_available_scripts),
	OPT_CALLBACK('s', "script", NULL, "name",
		     "script file name (lang:script name, script name, or *)",
		     parse_scriptname),
	OPT_STRING('g', "gen-script", &generate_script_lang, "lang",
		   "generate perf-script.xx script in specified language"),
	OPT_STRING('i', "input", &input_name, "file", "input file name"),
	OPT_BOOLEAN('d', "debug-mode", &debug_mode,
		   "do various checks like samples ordering and lost events"),
	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
		   "file", "vmlinux pathname"),
	OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
		   "file", "kallsyms pathname"),
	OPT_BOOLEAN('G', "hide-call-graph", &no_callchain,
		    "When printing symbols do not display call chain"),
	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
		    "Look for files with symbols relative to this directory"),
	OPT_CALLBACK('f', "fields", NULL, "str",
		     "comma separated output fields prepend with 'type:'. "
		     "Valid types: hw,sw,trace,raw. "
		     "Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,"
		     "addr,symoff", parse_output_fields),
	OPT_BOOLEAN('a', "all-cpus", &system_wide,
		    "system-wide collection from all CPUs"),
	OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
		   "only consider these symbols"),
	OPT_STRING('C', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
	OPT_STRING('c', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
		   "only display events for these comms"),
	OPT_BOOLEAN('I', "show-info", &show_full_info,
		    "display extended information from perf.data file"),
	OPT_BOOLEAN('\0', "show-kernel-path", &symbol_conf.show_kernel_path,
		    "Show the path of [kernel.kallsyms]"),
	OPT_END()
	};
	const char * const script_usage[] = {
		"perf script [<options>]",
		"perf script [<options>] record <script> [<record-options>] <command>",
		"perf script [<options>] report <script> [script-args]",
		"perf script [<options>] <script> [<record-options>] <command>",
		"perf script [<options>] <top-script> [script-args]",
		NULL
	};

	setup_scripting();

	argc = parse_options(argc, argv, options, script_usage,
			     PARSE_OPT_STOP_AT_NON_OPTION);

	if (argc > 1 && !strncmp(argv[0], "rec", strlen("rec"))) {
		rec_script_path = get_script_path(argv[1], RECORD_SUFFIX);
		if (!rec_script_path)
			return cmd_record(argc, argv, NULL);
	}

	if (argc > 1 && !strncmp(argv[0], "rep", strlen("rep"))) {
		rep_script_path = get_script_path(argv[1], REPORT_SUFFIX);
		if (!rep_script_path) {
			fprintf(stderr,
				"Please specify a valid report script"
				"(see 'perf script -l' for listing)\n");
			return -1;
		}
	}

	/* make sure PERF_EXEC_PATH is set for scripts */
	perf_set_argv_exec_path(perf_exec_path());

	if (argc && !script_name && !rec_script_path && !rep_script_path) {
		int live_pipe[2];
		int rep_args;
		pid_t pid;

		rec_script_path = get_script_path(argv[0], RECORD_SUFFIX);
		rep_script_path = get_script_path(argv[0], REPORT_SUFFIX);

		if (!rec_script_path && !rep_script_path) {
			fprintf(stderr, " Couldn't find script %s\n\n See perf"
				" script -l for available scripts.\n", argv[0]);
			usage_with_options(script_usage, options);
		}

		if (is_top_script(argv[0])) {
			rep_args = argc - 1;
		} else {
			int rec_args;

			rep_args = has_required_arg(rep_script_path);
			rec_args = (argc - 1) - rep_args;
			if (rec_args < 0) {
				fprintf(stderr, " %s script requires options."
					"\n\n See perf script -l for available "
					"scripts and options.\n", argv[0]);
				usage_with_options(script_usage, options);
			}
		}

		if (pipe(live_pipe) < 0) {
			perror("failed to create pipe");
			return -1;
		}

		pid = fork();
		if (pid < 0) {
			perror("failed to fork");
			return -1;
		}

		if (!pid) {
			j = 0;

			dup2(live_pipe[1], 1);
			close(live_pipe[0]);

			if (is_top_script(argv[0])) {
				system_wide = true;
			} else if (!system_wide) {
				if (have_cmd(argc - rep_args, &argv[rep_args]) != 0) {
					err = -1;
					goto out;
				}
			}

			__argv = malloc((argc + 6) * sizeof(const char *));
			if (!__argv) {
				pr_err("malloc failed\n");
				err = -ENOMEM;
				goto out;
			}

			__argv[j++] = "/bin/sh";
			__argv[j++] = rec_script_path;
			if (system_wide)
				__argv[j++] = "-a";
			__argv[j++] = "-q";
			__argv[j++] = "-o";
			__argv[j++] = "-";
			for (i = rep_args + 1; i < argc; i++)
				__argv[j++] = argv[i];
			__argv[j++] = NULL;

			execvp("/bin/sh", (char **)__argv);
			free(__argv);
			exit(-1);
		}

		dup2(live_pipe[0], 0);
		close(live_pipe[1]);

		__argv = malloc((argc + 4) * sizeof(const char *));
		if (!__argv) {
			pr_err("malloc failed\n");
			err = -ENOMEM;
			goto out;
		}

		j = 0;
		__argv[j++] = "/bin/sh";
		__argv[j++] = rep_script_path;
		for (i = 1; i < rep_args + 1; i++)
			__argv[j++] = argv[i];
		__argv[j++] = "-i";
		__argv[j++] = "-";
		__argv[j++] = NULL;

		execvp("/bin/sh", (char **)__argv);
		free(__argv);
		exit(-1);
	}

	if (rec_script_path)
		script_path = rec_script_path;
	if (rep_script_path)
		script_path = rep_script_path;

	if (script_path) {
		j = 0;

		if (!rec_script_path)
			system_wide = false;
		else if (!system_wide) {
			if (have_cmd(argc - 1, &argv[1]) != 0) {
				err = -1;
				goto out;
			}
		}

		__argv = malloc((argc + 2) * sizeof(const char *));
		if (!__argv) {
			pr_err("malloc failed\n");
			err = -ENOMEM;
			goto out;
		}

		__argv[j++] = "/bin/sh";
		__argv[j++] = script_path;
		if (system_wide)
			__argv[j++] = "-a";
		for (i = 2; i < argc; i++)
			__argv[j++] = argv[i];
		__argv[j++] = NULL;

		execvp("/bin/sh", (char **)__argv);
		free(__argv);
		exit(-1);
	}

	if (symbol__init() < 0)
		return -1;
	if (!script_name)
		setup_pager();

	session = perf_session__new(input_name, O_RDONLY, 0, false,
				    &perf_script);
	if (session == NULL)
		return -ENOMEM;

	if (cpu_list) {
		if (perf_session__cpu_bitmap(session, cpu_list, cpu_bitmap))
			return -1;
	}

	perf_session__fprintf_info(session, stdout, show_full_info);

	if (!no_callchain)
		symbol_conf.use_callchain = true;
	else
		symbol_conf.use_callchain = false;

	if (generate_script_lang) {
		struct stat perf_stat;
		int input;

		if (output_set_by_user()) {
			fprintf(stderr,
				"custom fields not supported for generated scripts");
			return -1;
		}

		input = open(session->filename, O_RDONLY);	/* input_name */
		if (input < 0) {
			perror("failed to open file");
			return -1;
		}

		err = fstat(input, &perf_stat);
		if (err < 0) {
			perror("failed to stat file");
			return -1;
		}

		if (!perf_stat.st_size) {
			fprintf(stderr, "zero-sized file, nothing to do!\n");
			return 0;
		}

		scripting_ops = script_spec__lookup(generate_script_lang);
		if (!scripting_ops) {
			fprintf(stderr, "invalid language specifier");
			return -1;
		}

		err = scripting_ops->generate_script(session->pevent,
						     "perf-script");
		goto out;
	}

	if (script_name) {
		err = scripting_ops->start_script(script_name, argc, argv);
		if (err)
			goto out;
		pr_debug("perf script started with script %s\n\n", script_name);
	}


	err = perf_session__check_output_opt(session);
	if (err < 0)
		goto out;

	err = __cmd_script(session);

	perf_session__delete(session);
	cleanup_scripting();
out:
	return err;
}