tools/perf/util/config.c - kernel/lockdown - Git at Google

 /*
  * config.c
  *
  * Helper functions for parsing config items.
  * Originally copied from GIT source.
  *
  * Copyright (C) Linus Torvalds, 2005
  * Copyright (C) Johannes Schindelin, 2005
  *
  */
 #include "util.h"
 #include "cache.h"
 #include "exec_cmd.h"

 #define MAXNAME (256)

 #define DEBUG_CACHE_DIR ".debug"


 char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */

 static FILE *config_file;
 static const char *config_file_name;
 static int config_linenr;
 static int config_file_eof;

 static const char *config_exclusive_filename;

 static int get_next_char(void)
 {
 	int c;
 	FILE *f;

 	c = '\n';
 	if ((f = config_file) != NULL) {
 		c = fgetc(f);
 		if (c == '\r') {
 			/* DOS like systems */
 			c = fgetc(f);
 			if (c != '\n') {
 				ungetc(c, f);
 				c = '\r';
 			}
 		}
 		if (c == '\n')
 			config_linenr++;
 		if (c == EOF) {
 			config_file_eof = 1;
 			c = '\n';
 		}
 	}
 	return c;
 }

 static char *parse_value(void)
 {
 	static char value[1024];
 	int quote = 0, comment = 0, space = 0;
 	size_t len = 0;

 	for (;;) {
 		int c = get_next_char();

 		if (len >= sizeof(value) - 1)
 			return NULL;
 		if (c == '\n') {
 			if (quote)
 				return NULL;
 			value[len] = 0;
 			return value;
 		}
 		if (comment)
 			continue;
 		if (isspace(c) && !quote) {
 			space = 1;
 			continue;
 		}
 		if (!quote) {
 			if (c == ';' || c == '#') {
 				comment = 1;
 				continue;
 			}
 		}
 		if (space) {
 			if (len)
 				value[len++] = ' ';
 			space = 0;
 		}
 		if (c == '\\') {
 			c = get_next_char();
 			switch (c) {
 			case '\n':
 				continue;
 			case 't':
 				c = '\t';
 				break;
 			case 'b':
 				c = '\b';
 				break;
 			case 'n':
 				c = '\n';
 				break;
 			/* Some characters escape as themselves */
 			case '\\': case '"':
 				break;
 			/* Reject unknown escape sequences */
 			default:
 				return NULL;
 			}
 			value[len++] = c;
 			continue;
 		}
 		if (c == '"') {
 			quote = 1-quote;
 			continue;
 		}
 		value[len++] = c;
 	}
 }

 static inline int iskeychar(int c)
 {
 	return isalnum(c) || c == '-' || c == '_';
 }

 static int get_value(config_fn_t fn, void *data, char *name, unsigned int len)
 {
 	int c;
 	char *value;

 	/* Get the full name */
 	for (;;) {
 		c = get_next_char();
 		if (config_file_eof)
 			break;
 		if (!iskeychar(c))
 			break;
 		name[len++] = c;
 		if (len >= MAXNAME)
 			return -1;
 	}
 	name[len] = 0;
 	while (c == ' ' || c == '\t')
 		c = get_next_char();

 	value = NULL;
 	if (c != '\n') {
 		if (c != '=')
 			return -1;
 		value = parse_value();
 		if (!value)
 			return -1;
 	}
 	return fn(name, value, data);
 }

 static int get_extended_base_var(char *name, int baselen, int c)
 {
 	do {
 		if (c == '\n')
 			return -1;
 		c = get_next_char();
 	} while (isspace(c));

 	/* We require the format to be '[base "extension"]' */
 	if (c != '"')
 		return -1;
 	name[baselen++] = '.';

 	for (;;) {
 		int ch = get_next_char();

 		if (ch == '\n')
 			return -1;
 		if (ch == '"')
 			break;
 		if (ch == '\\') {
 			ch = get_next_char();
 			if (ch == '\n')
 				return -1;
 		}
 		name[baselen++] = ch;
 		if (baselen > MAXNAME / 2)
 			return -1;
 	}

 	/* Final ']' */
 	if (get_next_char() != ']')
 		return -1;
 	return baselen;
 }

 static int get_base_var(char *name)
 {
 	int baselen = 0;

 	for (;;) {
 		int c = get_next_char();
 		if (config_file_eof)
 			return -1;
 		if (c == ']')
 			return baselen;
 		if (isspace(c))
 			return get_extended_base_var(name, baselen, c);
 		if (!iskeychar(c) && c != '.')
 			return -1;
 		if (baselen > MAXNAME / 2)
 			return -1;
 		name[baselen++] = tolower(c);
 	}
 }

 static int perf_parse_file(config_fn_t fn, void *data)
 {
 	int comment = 0;
 	int baselen = 0;
 	static char var[MAXNAME];

 	/* U+FEFF Byte Order Mark in UTF8 */
 	static const unsigned char *utf8_bom = (unsigned char *) "\xef\xbb\xbf";
 	const unsigned char *bomptr = utf8_bom;

 	for (;;) {
 		int c = get_next_char();
 		if (bomptr && *bomptr) {
 			/* We are at the file beginning; skip UTF8-encoded BOM
 			 * if present. Sane editors won't put this in on their
 			 * own, but e.g. Windows Notepad will do it happily. */
 			if ((unsigned char) c == *bomptr) {
 				bomptr++;
 				continue;
 			} else {
 				/* Do not tolerate partial BOM. */
 				if (bomptr != utf8_bom)
 					break;
 				/* No BOM at file beginning. Cool. */
 				bomptr = NULL;
 			}
 		}
 		if (c == '\n') {
 			if (config_file_eof)
 				return 0;
 			comment = 0;
 			continue;
 		}
 		if (comment || isspace(c))
 			continue;
 		if (c == '#' || c == ';') {
 			comment = 1;
 			continue;
 		}
 		if (c == '[') {
 			baselen = get_base_var(var);
 			if (baselen <= 0)
 				break;
 			var[baselen++] = '.';
 			var[baselen] = 0;
 			continue;
 		}
 		if (!isalpha(c))
 			break;
 		var[baselen] = tolower(c);
 		if (get_value(fn, data, var, baselen+1) < 0)
 			break;
 	}
 	die("bad config file line %d in %s", config_linenr, config_file_name);
 }

 static int parse_unit_factor(const char *end, unsigned long *val)
 {
 	if (!*end)
 		return 1;
 	else if (!strcasecmp(end, "k")) {
 		*val *= 1024;
 		return 1;
 	}
 	else if (!strcasecmp(end, "m")) {
 		*val *= 1024 * 1024;
 		return 1;
 	}
 	else if (!strcasecmp(end, "g")) {
 		*val *= 1024 * 1024 * 1024;
 		return 1;
 	}
 	return 0;
 }

 static int perf_parse_long(const char *value, long *ret)
 {
 	if (value && *value) {
 		char *end;
 		long val = strtol(value, &end, 0);
 		unsigned long factor = 1;
 		if (!parse_unit_factor(end, &factor))
 			return 0;
 		*ret = val * factor;
 		return 1;
 	}
 	return 0;
 }

 static void die_bad_config(const char *name)
 {
 	if (config_file_name)
 		die("bad config value for '%s' in %s", name, config_file_name);
 	die("bad config value for '%s'", name);
 }

 int perf_config_int(const char *name, const char *value)
 {
 	long ret = 0;
 	if (!perf_parse_long(value, &ret))
 		die_bad_config(name);
 	return ret;
 }

 static int perf_config_bool_or_int(const char *name, const char *value, int *is_bool)
 {
 	*is_bool = 1;
 	if (!value)
 		return 1;
 	if (!*value)
 		return 0;
 	if (!strcasecmp(value, "true") || !strcasecmp(value, "yes") || !strcasecmp(value, "on"))
 		return 1;
 	if (!strcasecmp(value, "false") || !strcasecmp(value, "no") || !strcasecmp(value, "off"))
 		return 0;
 	*is_bool = 0;
 	return perf_config_int(name, value);
 }

 int perf_config_bool(const char *name, const char *value)
 {
 	int discard;
 	return !!perf_config_bool_or_int(name, value, &discard);
 }

 const char *perf_config_dirname(const char *name, const char *value)
 {
 	if (!name)
 		return NULL;
 	return value;
 }

 static int perf_default_core_config(const char *var __maybe_unused,
 				    const char *value __maybe_unused)
 {
 	/* Add other config variables here. */
 	return 0;
 }

 int perf_default_config(const char *var, const char *value,
 			void *dummy __maybe_unused)
 {
 	if (!prefixcmp(var, "core."))
 		return perf_default_core_config(var, value);

 	/* Add other config variables here. */
 	return 0;
 }

 static int perf_config_from_file(config_fn_t fn, const char *filename, void *data)
 {
 	int ret;
 	FILE *f = fopen(filename, "r");

 	ret = -1;
 	if (f) {
 		config_file = f;
 		config_file_name = filename;
 		config_linenr = 1;
 		config_file_eof = 0;
 		ret = perf_parse_file(fn, data);
 		fclose(f);
 		config_file_name = NULL;
 	}
 	return ret;
 }

 static const char *perf_etc_perfconfig(void)
 {
 	static const char *system_wide;
 	if (!system_wide)
 		system_wide = system_path(ETC_PERFCONFIG);
 	return system_wide;
 }

 static int perf_env_bool(const char *k, int def)
 {
 	const char *v = getenv(k);
 	return v ? perf_config_bool(k, v) : def;
 }

 static int perf_config_system(void)
 {
 	return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0);
 }

 static int perf_config_global(void)
 {
 	return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
 }

 int perf_config(config_fn_t fn, void *data)
 {
 	int ret = 0, found = 0;
 	const char *home = NULL;

 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
 	if (config_exclusive_filename)
 		return perf_config_from_file(fn, config_exclusive_filename, data);
 	if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
 		ret += perf_config_from_file(fn, perf_etc_perfconfig(),
 					    data);
 		found += 1;
 	}

 	home = getenv("HOME");
 	if (perf_config_global() && home) {
 		char *user_config = strdup(mkpath("%s/.perfconfig", home));
 		struct stat st;

 		if (user_config == NULL) {
 			warning("Not enough memory to process %s/.perfconfig, "
 				"ignoring it.", home);
 			goto out;
 		}

 		if (stat(user_config, &st) < 0)
 			goto out_free;

 		if (st.st_uid && (st.st_uid != geteuid())) {
 			warning("File %s not owned by current user or root, "
 				"ignoring it.", user_config);
 			goto out_free;
 		}

 		if (!st.st_size)
 			goto out_free;

 		ret += perf_config_from_file(fn, user_config, data);
 		found += 1;
 out_free:
 		free(user_config);
 	}
 out:
 	if (found == 0)
 		return -1;
 	return ret;
 }

 /*
  * Call this to report error for your variable that should not
  * get a boolean value (i.e. "[my] var" means "true").
  */
 int config_error_nonbool(const char *var)
 {
 	return error("Missing value for '%s'", var);
 }

 struct buildid_dir_config {
 	char *dir;
 };

 static int buildid_dir_command_config(const char *var, const char *value,
 				      void *data)
 {
 	struct buildid_dir_config *c = data;
 	const char *v;

 	/* same dir for all commands */
 	if (!prefixcmp(var, "buildid.") && !strcmp(var + 8, "dir")) {
 		v = perf_config_dirname(var, value);
 		if (!v)
 			return -1;
 		strncpy(c->dir, v, MAXPATHLEN-1);
 		c->dir[MAXPATHLEN-1] = '\0';
 	}
 	return 0;
 }

 static void check_buildid_dir_config(void)
 {
 	struct buildid_dir_config c;
 	c.dir = buildid_dir;
 	perf_config(buildid_dir_command_config, &c);
 }

 void set_buildid_dir(void)
 {
 	buildid_dir[0] = '\0';

 	/* try config file */
 	check_buildid_dir_config();

 	/* default to $HOME/.debug */
 	if (buildid_dir[0] == '\0') {
 		char *v = getenv("HOME");
 		if (v) {
 			snprintf(buildid_dir, MAXPATHLEN-1, "%s/%s",
 				 v, DEBUG_CACHE_DIR);
 		} else {
 			strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1);
 		}
 		buildid_dir[MAXPATHLEN-1] = '\0';
 	}
 	/* for communicating with external commands */
 	setenv("PERF_BUILDID_DIR", buildid_dir, 1);
 }
	/*
	* config.c
	*
	* Helper functions for parsing config items.
	* Originally copied from GIT source.
	*
	* Copyright (C) Linus Torvalds, 2005
	* Copyright (C) Johannes Schindelin, 2005
	*
	*/
	#include "util.h"
	#include "cache.h"
	#include "exec_cmd.h"

	#define MAXNAME (256)

	#define DEBUG_CACHE_DIR ".debug"


	char buildid_dir[MAXPATHLEN]; /* root dir for buildid, binary cache */

	static FILE *config_file;
	static const char *config_file_name;
	static int config_linenr;
	static int config_file_eof;

	static const char *config_exclusive_filename;

	static int get_next_char(void)
	{
	int c;
	FILE *f;

	c = '\n';
	if ((f = config_file) != NULL) {
	c = fgetc(f);
	if (c == '\r') {
	/* DOS like systems */
	c = fgetc(f);
	if (c != '\n') {
	ungetc(c, f);
	c = '\r';
	}
	}
	if (c == '\n')
	config_linenr++;
	if (c == EOF) {
	config_file_eof = 1;
	c = '\n';
	}
	}
	return c;
	}

	static char *parse_value(void)
	{
	static char value[1024];
	int quote = 0, comment = 0, space = 0;
	size_t len = 0;

	for (;;) {
	int c = get_next_char();

	if (len >= sizeof(value) - 1)
	return NULL;
	if (c == '\n') {
	if (quote)
	return NULL;
	value[len] = 0;
	return value;
	}
	if (comment)
	continue;
	if (isspace(c) && !quote) {
	space = 1;
	continue;
	}
	if (!quote) {
	if (c == ';' \|\| c == '#') {
	comment = 1;
	continue;
	}
	}
	if (space) {
	if (len)
	value[len++] = ' ';
	space = 0;
	}
	if (c == '\\') {
	c = get_next_char();
	switch (c) {
	case '\n':
	continue;
	case 't':
	c = '\t';
	break;
	case 'b':
	c = '\b';
	break;
	case 'n':
	c = '\n';
	break;
	/* Some characters escape as themselves */
	case '\\': case '"':
	break;
	/* Reject unknown escape sequences */
	default:
	return NULL;
	}
	value[len++] = c;
	continue;
	}
	if (c == '"') {
	quote = 1-quote;
	continue;
	}
	value[len++] = c;
	}
	}

	static inline int iskeychar(int c)
	{
	return isalnum(c) \|\| c == '-' \|\| c == '_';
	}

	static int get_value(config_fn_t fn, void data, char name, unsigned int len)
	{
	int c;
	char *value;

	/* Get the full name */
	for (;;) {
	c = get_next_char();
	if (config_file_eof)
	break;
	if (!iskeychar(c))
	break;
	name[len++] = c;
	if (len >= MAXNAME)
	return -1;
	}
	name[len] = 0;
	while (c == ' ' \|\| c == '\t')
	c = get_next_char();

	value = NULL;
	if (c != '\n') {
	if (c != '=')
	return -1;
	value = parse_value();
	if (!value)
	return -1;
	}
	return fn(name, value, data);
	}

	static int get_extended_base_var(char *name, int baselen, int c)
	{
	do {
	if (c == '\n')
	return -1;
	c = get_next_char();
	} while (isspace(c));

	/* We require the format to be '[base "extension"]' */
	if (c != '"')
	return -1;
	name[baselen++] = '.';

	for (;;) {
	int ch = get_next_char();

	if (ch == '\n')
	return -1;
	if (ch == '"')
	break;
	if (ch == '\\') {
	ch = get_next_char();
	if (ch == '\n')
	return -1;
	}
	name[baselen++] = ch;
	if (baselen > MAXNAME / 2)
	return -1;
	}

	/* Final ']' */
	if (get_next_char() != ']')
	return -1;
	return baselen;
	}

	static int get_base_var(char *name)
	{
	int baselen = 0;

	for (;;) {
	int c = get_next_char();
	if (config_file_eof)
	return -1;
	if (c == ']')
	return baselen;
	if (isspace(c))
	return get_extended_base_var(name, baselen, c);
	if (!iskeychar(c) && c != '.')
	return -1;
	if (baselen > MAXNAME / 2)
	return -1;
	name[baselen++] = tolower(c);
	}
	}

	static int perf_parse_file(config_fn_t fn, void *data)
	{
	int comment = 0;
	int baselen = 0;
	static char var[MAXNAME];

	/* U+FEFF Byte Order Mark in UTF8 */
	static const unsigned char utf8_bom = (unsigned char ) "\xef\xbb\xbf";
	const unsigned char *bomptr = utf8_bom;

	for (;;) {
	int c = get_next_char();
	if (bomptr && *bomptr) {
	/* We are at the file beginning; skip UTF8-encoded BOM
	* if present. Sane editors won't put this in on their
	* own, but e.g. Windows Notepad will do it happily. */
	if ((unsigned char) c == *bomptr) {
	bomptr++;
	continue;
	} else {
	/* Do not tolerate partial BOM. */
	if (bomptr != utf8_bom)
	break;
	/* No BOM at file beginning. Cool. */
	bomptr = NULL;
	}
	}
	if (c == '\n') {
	if (config_file_eof)
	return 0;
	comment = 0;
	continue;
	}
	if (comment \|\| isspace(c))
	continue;
	if (c == '#' \|\| c == ';') {
	comment = 1;
	continue;
	}
	if (c == '[') {
	baselen = get_base_var(var);
	if (baselen <= 0)
	break;
	var[baselen++] = '.';
	var[baselen] = 0;
	continue;
	}
	if (!isalpha(c))
	break;
	var[baselen] = tolower(c);
	if (get_value(fn, data, var, baselen+1) < 0)
	break;
	}
	die("bad config file line %d in %s", config_linenr, config_file_name);
	}

	static int parse_unit_factor(const char end, unsigned long val)
	{
	if (!*end)
	return 1;
	else if (!strcasecmp(end, "k")) {
	val = 1024;
	return 1;
	}
	else if (!strcasecmp(end, "m")) {
	val = 1024 * 1024;
	return 1;
	}
	else if (!strcasecmp(end, "g")) {
	val = 1024 * 1024 * 1024;
	return 1;
	}
	return 0;
	}

	static int perf_parse_long(const char value, long ret)
	{
	if (value && *value) {
	char *end;
	long val = strtol(value, &end, 0);
	unsigned long factor = 1;
	if (!parse_unit_factor(end, &factor))
	return 0;
	ret = val factor;
	return 1;
	}
	return 0;
	}

	static void die_bad_config(const char *name)
	{
	if (config_file_name)
	die("bad config value for '%s' in %s", name, config_file_name);
	die("bad config value for '%s'", name);
	}

	int perf_config_int(const char name, const char value)
	{
	long ret = 0;
	if (!perf_parse_long(value, &ret))
	die_bad_config(name);
	return ret;
	}

	static int perf_config_bool_or_int(const char name, const char value, int *is_bool)
	{
	*is_bool = 1;
	if (!value)
	return 1;
	if (!*value)
	return 0;
	if (!strcasecmp(value, "true") \|\| !strcasecmp(value, "yes") \|\| !strcasecmp(value, "on"))
	return 1;
	if (!strcasecmp(value, "false") \|\| !strcasecmp(value, "no") \|\| !strcasecmp(value, "off"))
	return 0;
	*is_bool = 0;
	return perf_config_int(name, value);
	}

	int perf_config_bool(const char name, const char value)
	{
	int discard;
	return !!perf_config_bool_or_int(name, value, &discard);
	}

	const char perf_config_dirname(const char name, const char *value)
	{
	if (!name)
	return NULL;
	return value;
	}

	static int perf_default_core_config(const char *var __maybe_unused,
	const char *value __maybe_unused)
	{
	/* Add other config variables here. */
	return 0;
	}

	int perf_default_config(const char var, const char value,
	void *dummy __maybe_unused)
	{
	if (!prefixcmp(var, "core."))
	return perf_default_core_config(var, value);

	/* Add other config variables here. */
	return 0;
	}

	static int perf_config_from_file(config_fn_t fn, const char filename, void data)
	{
	int ret;
	FILE *f = fopen(filename, "r");

	ret = -1;
	if (f) {
	config_file = f;
	config_file_name = filename;
	config_linenr = 1;
	config_file_eof = 0;
	ret = perf_parse_file(fn, data);
	fclose(f);
	config_file_name = NULL;
	}
	return ret;
	}

	static const char *perf_etc_perfconfig(void)
	{
	static const char *system_wide;
	if (!system_wide)
	system_wide = system_path(ETC_PERFCONFIG);
	return system_wide;
	}

	static int perf_env_bool(const char *k, int def)
	{
	const char *v = getenv(k);
	return v ? perf_config_bool(k, v) : def;
	}

	static int perf_config_system(void)
	{
	return !perf_env_bool("PERF_CONFIG_NOSYSTEM", 0);
	}

	static int perf_config_global(void)
	{
	return !perf_env_bool("PERF_CONFIG_NOGLOBAL", 0);
	}

	int perf_config(config_fn_t fn, void *data)
	{
	int ret = 0, found = 0;
	const char *home = NULL;

	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
	if (config_exclusive_filename)
	return perf_config_from_file(fn, config_exclusive_filename, data);
	if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK)) {
	ret += perf_config_from_file(fn, perf_etc_perfconfig(),
	data);
	found += 1;
	}

	home = getenv("HOME");
	if (perf_config_global() && home) {
	char *user_config = strdup(mkpath("%s/.perfconfig", home));
	struct stat st;

	if (user_config == NULL) {
	warning("Not enough memory to process %s/.perfconfig, "
	"ignoring it.", home);
	goto out;
	}

	if (stat(user_config, &st) < 0)
	goto out_free;

	if (st.st_uid && (st.st_uid != geteuid())) {
	warning("File %s not owned by current user or root, "
	"ignoring it.", user_config);
	goto out_free;
	}

	if (!st.st_size)
	goto out_free;

	ret += perf_config_from_file(fn, user_config, data);
	found += 1;
	out_free:
	free(user_config);
	}
	out:
	if (found == 0)
	return -1;
	return ret;
	}

	/*
	* Call this to report error for your variable that should not
	* get a boolean value (i.e. "[my] var" means "true").
	*/
	int config_error_nonbool(const char *var)
	{
	return error("Missing value for '%s'", var);
	}

	struct buildid_dir_config {
	char *dir;
	};

	static int buildid_dir_command_config(const char var, const char value,
	void *data)
	{
	struct buildid_dir_config *c = data;
	const char *v;

	/* same dir for all commands */
	if (!prefixcmp(var, "buildid.") && !strcmp(var + 8, "dir")) {
	v = perf_config_dirname(var, value);
	if (!v)
	return -1;
	strncpy(c->dir, v, MAXPATHLEN-1);
	c->dir[MAXPATHLEN-1] = '\0';
	}
	return 0;
	}

	static void check_buildid_dir_config(void)
	{
	struct buildid_dir_config c;
	c.dir = buildid_dir;
	perf_config(buildid_dir_command_config, &c);
	}

	void set_buildid_dir(void)
	{
	buildid_dir[0] = '\0';

	/* try config file */
	check_buildid_dir_config();

	/* default to $HOME/.debug */
	if (buildid_dir[0] == '\0') {
	char *v = getenv("HOME");
	if (v) {
	snprintf(buildid_dir, MAXPATHLEN-1, "%s/%s",
	v, DEBUG_CACHE_DIR);
	} else {
	strncpy(buildid_dir, DEBUG_CACHE_DIR, MAXPATHLEN-1);
	}
	buildid_dir[MAXPATHLEN-1] = '\0';
	}
	/* for communicating with external commands */
	setenv("PERF_BUILDID_DIR", buildid_dir, 1);
	}