15 typedef std::string string;
16 typedef std::string::iterator string_iterator;
18 // Utility function to skip white space. Returns an iterator at the
19 // first non-white-space position (or at end).
20 static string_iterator skipws(string_iterator i, string_iterator end)
26 if (! isspace(*i, locale::classic())) {
34 // Read a setting name.
35 static string read_setting_name(string_iterator & i, string_iterator end)
41 const ctype<char> & facet = use_facet<ctype<char> >(locale::classic());
44 // Allow alphabetical characters, and dash (-) in setting name
45 while (i != end && (*i == '-' || facet.is(ctype<char>::alpha, *i))) {
53 class SettingException
58 SettingException(const std::string &&exc_info) : info(std::move(exc_info))
62 std::string &getInfo()
70 // Read a setting value
72 // In general a setting value is a single-line string. It may contain multiple parts
73 // separated by white space (which is normally collapsed). A hash mark - # - denotes
74 // the end of the value and the beginning of a comment (it should be preceded by
77 // Part of a value may be quoted using double quote marks, which prevents collapse
78 // of whitespace and interpretation of most special characters (the quote marks will
79 // not be considered part of the value). A backslash can precede a character (such
80 // as '#' or '"' or another backslash) to remove its special meaning. Newline
81 // characters are not allowed in values and cannot be quoted.
83 // This function expects the string to be in an ASCII-compatible, single byte
84 // encoding (the "classic" locale).
87 // service_name - the name of the service to which the setting applies
88 // i - reference to string iterator through the line
89 // end - iterator at end of line
90 // part_positions - list of <int,int> to which the position of each setting value
91 // part will be added as [start,end). May be null.
92 static string read_setting_value(string_iterator & i, string_iterator end,
93 std::list<std::pair<unsigned,unsigned>> * part_positions = nullptr)
101 bool new_part = true;
108 part_start = rval.length();
115 if (c == '\"') break;
117 throw SettingException("Line end inside quoted string");
119 else if (c == '\\') {
120 // A backslash escapes the following character.
125 throw SettingException("Line end follows backslash escape character (`\\')");
136 // String wasn't terminated
137 throw SettingException("Unterminated quoted string");
140 else if (c == '\\') {
142 part_start = rval.length();
145 // A backslash escapes the next character
151 throw SettingException("Backslash escape (`\\') not followed by character");
154 else if (isspace(c, locale::classic())) {
155 if (! new_part && part_positions != nullptr) {
156 part_positions->emplace_back(part_start, rval.length());
161 if (*i == '#') break; // comment
162 rval += ' '; // collapse ws to a single space
166 // Possibly intended a comment; we require leading whitespace to reduce occurrence of accidental
167 // comments in setting values.
168 throw SettingException("hashmark (`#') comment must be separated from setting value by whitespace");
172 part_start = rval.length();
181 if (part_positions != nullptr) {
182 part_positions->emplace_back(part_start, rval.length());
188 static int signalNameToNumber(std::string &signame)
190 if (signame == "HUP") return SIGHUP;
191 if (signame == "INT") return SIGINT;
192 if (signame == "QUIT") return SIGQUIT;
193 if (signame == "USR1") return SIGUSR1;
194 if (signame == "USR2") return SIGUSR2;
198 static const char * uid_err_msg = "Specified user id contains invalid numeric characters or is outside allowed range.";
200 // Parse a userid parameter which may be a numeric user ID or a username. If a name, the
201 // userid is looked up via the system user database (getpwnam() function). In this case,
202 // the associated group is stored in the location specified by the group_p parameter iff
203 // it is not null and iff it contains the value -1.
204 static uid_t parse_uid_param(const std::string ¶m, const std::string &service_name, gid_t *group_p)
206 // Could be a name or a numeric id. But we should assume numeric first, just in case
207 // a user manages to give themselves a username that parses as a number.
210 // POSIX does not specify whether uid_t is an signed or unsigned, but regardless
211 // is is probably safe to assume that valid values are positive. We'll also assert
212 // that the value range fits within "unsigned long long" since it seems unlikely
213 // that would ever not be the case.
214 static_assert((uintmax_t)std::numeric_limits<uid_t>::max() <= (uintmax_t)std::numeric_limits<unsigned long long>::max(), "uid_t is too large");
215 unsigned long long v = std::stoull(param, &ind, 0);
216 if (v > static_cast<unsigned long long>(std::numeric_limits<uid_t>::max()) || ind != param.length()) {
217 throw service_description_exc(service_name, uid_err_msg);
221 catch (std::out_of_range &exc) {
222 throw service_description_exc(service_name, uid_err_msg);
224 catch (std::invalid_argument &exc) {
225 // Ok, so it doesn't look like a number: proceed...
229 struct passwd * pwent = getpwnam(param.c_str());
230 if (pwent == nullptr) {
231 // Maybe an error, maybe just no entry.
233 throw service_description_exc(service_name, "Specified user \"" + param + "\" does not exist in system database.");
236 throw service_description_exc(service_name, std::string("Error accessing user database: ") + strerror(errno));
240 if (group_p && *group_p != (gid_t)-1) {
241 *group_p = pwent->pw_gid;
244 return pwent->pw_uid;
247 static const char * num_err_msg = "Specified value contains invalid numeric characters or is outside allowed range.";
249 // Parse an unsigned numeric parameter value
250 static unsigned long long parse_unum_param(const std::string ¶m, const std::string &service_name,
251 unsigned long long max = std::numeric_limits<unsigned long long>::max())
255 unsigned long long v = std::stoull(param, &ind, 0);
256 if (v > max || ind != param.length()) {
257 throw service_description_exc(service_name, num_err_msg);
261 catch (std::out_of_range &exc) {
262 throw service_description_exc(service_name, num_err_msg);
264 catch (std::invalid_argument &exc) {
265 throw service_description_exc(service_name, num_err_msg);
269 static const char * gid_err_msg = "Specified group id contains invalid numeric characters or is outside allowed range.";
271 static gid_t parse_gid_param(const std::string ¶m, const std::string &service_name)
273 // Could be a name or a numeric id. But we should assume numeric first, just in case
274 // a user manages to give themselves a username that parses as a number.
277 // POSIX does not specify whether uid_t is an signed or unsigned, but regardless
278 // is is probably safe to assume that valid values are positive. We'll also assume
279 // that the value range fits with "unsigned long long" since it seems unlikely
280 // that would ever not be the case.
282 // TODO perhaps write a number parser, since even the unsigned variants of the C/C++
283 // functions accept a leading minus sign...
284 unsigned long long v = std::stoull(param, &ind, 0);
285 if (v > static_cast<unsigned long long>(std::numeric_limits<gid_t>::max()) || ind != param.length()) {
286 throw service_description_exc(service_name, gid_err_msg);
290 catch (std::out_of_range &exc) {
291 throw service_description_exc(service_name, gid_err_msg);
293 catch (std::invalid_argument &exc) {
294 // Ok, so it doesn't look like a number: proceed...
298 struct group * grent = getgrnam(param.c_str());
299 if (grent == nullptr) {
300 // Maybe an error, maybe just no entry.
302 throw service_description_exc(service_name, "Specified group \"" + param + "\" does not exist in system database.");
305 throw service_description_exc(service_name, std::string("Error accessing group database: ") + strerror(errno));
309 return grent->gr_gid;
312 static void parse_timespec(const std::string ¶mval, const std::string &servicename,
313 const char * paramname, timespec &ts)
315 decltype(ts.tv_sec) isec = 0;
316 decltype(ts.tv_nsec) insec = 0;
317 auto max_secs = std::numeric_limits<decltype(isec)>::max() / 10;
318 auto len = paramval.length();
320 for (i = 0; i < len; i++) {
321 char ch = paramval[i];
326 if (ch < '0' || ch > '9') {
327 throw service_description_exc(servicename, std::string("Bad value for ") + paramname);
329 // check for overflow
330 if (isec >= max_secs) {
331 throw service_description_exc(servicename, std::string("Too-large value for ") + paramname);
336 decltype(insec) insec_m = 100000000; // 10^8
337 for ( ; i < len; i++) {
338 char ch = paramval[i];
339 if (ch < '0' || ch > '9') {
340 throw service_description_exc(servicename, std::string("Bad value for ") + paramname);
342 insec += (ch - '0') * insec_m;
349 // Find a service record, or load it from file. If the service has
350 // dependencies, load those also.
352 // Might throw a ServiceLoadExc exception if a dependency cycle is found or if another
353 // problem occurs (I/O error, service description not found etc). Throws std::bad_alloc
354 // if a memory allocation failure occurs.
355 service_record * dirload_service_set::load_service(const char * name)
367 // First try and find an existing record...
368 service_record * rval = find_service(string(name));
370 if (rval->isDummy()) {
371 throw service_cyclic_dependency(name);
376 // Couldn't find one. Have to load it.
377 string service_filename = service_dir;
378 if (*(service_filename.rbegin()) != '/') {
379 service_filename += '/';
381 service_filename += name;
384 list<pair<unsigned,unsigned>> command_offsets;
386 list<pair<unsigned,unsigned>> stop_command_offsets;
389 service_type service_type = service_type::PROCESS;
390 std::list<service_record *> depends_on;
391 std::list<service_record *> depends_soft;
393 onstart_flags_t onstart_flags;
394 int term_signal = -1; // additional termination signal
395 bool auto_restart = false;
396 bool smooth_recovery = false;
398 int socket_perms = 0666;
399 // Note: Posix allows that uid_t and gid_t may be unsigned types, but eg chown uses -1 as an
400 // invalid value, so it's safe to assume that we can do the same:
401 uid_t socket_uid = -1;
402 gid_t socket_gid = -1;
403 // Restart limit interval / count; default is 10 seconds, 3 restarts:
404 timespec restart_interval = { .tv_sec = 10, .tv_nsec = 0 };
405 int max_restarts = 3;
406 timespec restart_delay = { .tv_sec = 0, .tv_nsec = 200000000 };
409 ifstream service_file;
410 service_file.exceptions(ios::badbit | ios::failbit);
413 service_file.open(service_filename.c_str(), ios::in);
415 catch (std::ios_base::failure &exc) {
416 throw service_not_found(name);
419 // Add a dummy service record now to prevent infinite recursion in case of cyclic dependency
420 rval = new service_record(this, string(name));
424 // getline can set failbit if it reaches end-of-file, we don't want an exception in that case:
425 service_file.exceptions(ios::badbit);
427 while (! (service_file.rdstate() & ios::eofbit)) {
428 getline(service_file, line);
429 string::iterator i = line.begin();
430 string::iterator end = line.end();
435 continue; // comment line
437 string setting = read_setting_name(i, end);
439 if (i == end || (*i != '=' && *i != ':')) {
440 throw service_description_exc(name, "Badly formed line.");
442 i = skipws(++i, end);
444 if (setting == "command") {
445 command = read_setting_value(i, end, &command_offsets);
447 else if (setting == "socket-listen") {
448 socket_path = read_setting_value(i, end, nullptr);
450 else if (setting == "socket-permissions") {
451 string sock_perm_str = read_setting_value(i, end, nullptr);
454 socket_perms = std::stoi(sock_perm_str, &ind, 8);
455 if (ind != sock_perm_str.length()) {
456 throw std::logic_error("");
459 catch (std::logic_error &exc) {
460 throw service_description_exc(name, "socket-permissions: Badly-formed or out-of-range numeric value");
463 else if (setting == "socket-uid") {
464 string sock_uid_s = read_setting_value(i, end, nullptr);
465 socket_uid = parse_uid_param(sock_uid_s, name, &socket_gid);
467 else if (setting == "socket-gid") {
468 string sock_gid_s = read_setting_value(i, end, nullptr);
469 socket_gid = parse_gid_param(sock_gid_s, name);
471 else if (setting == "stop-command") {
472 stop_command = read_setting_value(i, end, &stop_command_offsets);
474 else if (setting == "pid-file") {
475 pid_file = read_setting_value(i, end);
477 else if (setting == "depends-on") {
478 string dependency_name = read_setting_value(i, end);
479 depends_on.push_back(load_service(dependency_name.c_str()));
481 else if (setting == "waits-for") {
482 string dependency_name = read_setting_value(i, end);
483 depends_soft.push_back(load_service(dependency_name.c_str()));
485 else if (setting == "logfile") {
486 logfile = read_setting_value(i, end);
488 else if (setting == "restart") {
489 string restart = read_setting_value(i, end);
490 auto_restart = (restart == "yes" || restart == "true");
492 else if (setting == "smooth-recovery") {
493 string recovery = read_setting_value(i, end);
494 smooth_recovery = (recovery == "yes" || recovery == "true");
496 else if (setting == "type") {
497 string type_str = read_setting_value(i, end);
498 if (type_str == "scripted") {
499 service_type = service_type::SCRIPTED;
501 else if (type_str == "process") {
502 service_type = service_type::PROCESS;
504 else if (type_str == "bgprocess") {
505 service_type = service_type::BGPROCESS;
507 else if (type_str == "internal") {
508 service_type = service_type::INTERNAL;
511 throw service_description_exc(name, "Service type must be one of: \"scripted\","
512 " \"process\", \"bgprocess\" or \"internal\"");
515 else if (setting == "options") {
516 std::list<std::pair<unsigned,unsigned>> indices;
517 string onstart_cmds = read_setting_value(i, end, &indices);
518 for (auto indexpair : indices) {
519 string option_txt = onstart_cmds.substr(indexpair.first, indexpair.second - indexpair.first);
520 if (option_txt == "starts-rwfs") {
521 onstart_flags.rw_ready = true;
523 else if (option_txt == "starts-log") {
524 onstart_flags.log_ready = true;
526 else if (option_txt == "no-sigterm") {
527 onstart_flags.no_sigterm = true;
529 else if (option_txt == "runs-on-console") {
530 onstart_flags.runs_on_console = true;
531 // A service that runs on the console necessarily starts on console:
532 onstart_flags.starts_on_console = true;
534 else if (option_txt == "starts-on-console") {
535 onstart_flags.starts_on_console = true;
537 else if (option_txt == "pass-cs-fd") {
538 onstart_flags.pass_cs_fd = true;
541 throw service_description_exc(name, "Unknown option: " + option_txt);
545 else if (setting == "termsignal") {
546 string signame = read_setting_value(i, end, nullptr);
547 int signo = signalNameToNumber(signame);
549 throw service_description_exc(name, "Unknown/unsupported termination signal: " + signame);
555 else if (setting == "restart-limit-interval") {
556 string interval_str = read_setting_value(i, end, nullptr);
557 parse_timespec(interval_str, name, "restart-limit-interval", restart_interval);
559 else if (setting == "restart-delay") {
560 string rsdelay_str = read_setting_value(i, end, nullptr);
561 parse_timespec(rsdelay_str, name, "restart-delay", restart_delay);
563 else if (setting == "restart-limit-count") {
564 string limit_str = read_setting_value(i, end, nullptr);
565 max_restarts = parse_unum_param(limit_str, name, std::numeric_limits<int>::max());
568 throw service_description_exc(name, "Unknown setting: " + setting);
573 service_file.close();
575 if (service_type == service_type::PROCESS || service_type == service_type::BGPROCESS || service_type == service_type::SCRIPTED) {
576 if (command.length() == 0) {
577 throw service_description_exc(name, "Service command not specified");
581 // Now replace the dummy service record with a real record:
582 for (auto iter = records.begin(); iter != records.end(); iter++) {
584 // We've found the dummy record
586 if (service_type == service_type::PROCESS) {
587 auto rvalps = new process_service(this, string(name), std::move(command),
588 command_offsets, &depends_on, &depends_soft);
589 rvalps->set_restart_interval(restart_interval, max_restarts);
590 rvalps->set_restart_delay(restart_delay);
593 else if (service_type == service_type::BGPROCESS) {
594 auto rvalps = new bgproc_service(this, string(name), std::move(command),
595 command_offsets, &depends_on, &depends_soft);
596 rvalps->set_pid_file(std::move(pid_file));
597 rvalps->set_restart_interval(restart_interval, max_restarts);
598 rvalps->set_restart_delay(restart_delay);
601 else if (service_type == service_type::SCRIPTED) {
602 rval = new scripted_service(this, string(name), std::move(command),
603 command_offsets, &depends_on, &depends_soft);
604 rval->setStopCommand(stop_command, stop_command_offsets);
607 rval = new service_record(this, string(name), service_type, std::move(command), command_offsets,
608 &depends_on, &depends_soft);
610 rval->setLogfile(logfile);
611 rval->setAutoRestart(auto_restart);
612 rval->setSmoothRecovery(smooth_recovery);
613 rval->setOnstartFlags(onstart_flags);
614 rval->setExtraTerminationSignal(term_signal);
615 rval->set_socket_details(std::move(socket_path), socket_perms, socket_uid, socket_gid);
623 catch (SettingException &setting_exc)
625 // Must remove the dummy service record.
626 std::remove(records.begin(), records.end(), rval);
628 throw service_description_exc(name, std::move(setting_exc.getInfo()));
631 // Must remove the dummy service record.
632 std::remove(records.begin(), records.end(), rval);