From: Andre Noll Date: Wed, 19 Mar 2008 23:36:44 +0000 (+0100) Subject: Implement SIGHUP handling. X-Git-Tag: v0.0.4~19^2 X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=f446dc1416090076177df45a568e195aaa9a8d1b;p=dss.git Implement SIGHUP handling. --- diff --git a/dss.c b/dss.c index 4bf01e9..24ef6cc 100644 --- a/dss.c +++ b/dss.c @@ -340,7 +340,10 @@ void free_snapshot_list(struct snapshot_list *sl) free(s); } free(sl->interval_count); + sl->interval_count = NULL; free(sl->snapshots); + sl->snapshots = NULL; + sl->num_snapshots = 0; } void stop_rsync_process(void) @@ -546,9 +549,95 @@ void kill_process(pid_t pid) kill(pid, SIGTERM); } -void handle_sighup() +int check_config(void) { - DSS_INFO_LOG("FIXME: no sighup handling yet\n"); + if (conf.unit_interval_arg <= 0) { + make_err_msg("bad unit interval: %i", conf.unit_interval_arg); + return -E_INVALID_NUMBER; + } + DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg); + if (conf.num_intervals_arg <= 0) { + make_err_msg("bad number of intervals %i", conf.num_intervals_arg); + return -E_INVALID_NUMBER; + } + DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg); + return 1; +} + +/* exits on errors */ +void parse_config_file(int override) +{ + int ret; + char *config_file; + struct stat statbuf; + char *old_logfile_arg = NULL; + int old_daemon_given = 0; + + if (conf.config_file_given) + config_file = dss_strdup(conf.config_file_arg); + else { + char *home = get_homedir(); + config_file = make_message("%s/.dssrc", home); + free(home); + } + if (override) { /* SIGHUP */ + if (conf.logfile_given) + old_logfile_arg = dss_strdup(conf.logfile_arg); + old_daemon_given = conf.daemon_given; + } + + ret = stat(config_file, &statbuf); + if (ret && conf.config_file_given) { + ret = -ERRNO_TO_DSS_ERROR(errno); + make_err_msg("failed to stat config file %s", config_file); + goto out; + } + if (!ret) { + struct cmdline_parser_params params = { + .override = override, + .initialize = 0, + .check_required = 0, + .check_ambiguity = 0 + }; + cmdline_parser_config_file(config_file, &conf, ¶ms); + } + if (!conf.source_dir_given || !conf.dest_dir_given) { + ret = -E_SYNTAX; + make_err_msg("you need to specify both source_dir and dest_dir"); + goto out; + } + ret = check_config(); + if (ret < 0) + goto out; + if (override) { + /* don't change daemon mode on SIGHUP */ + conf.daemon_given = old_daemon_given; + close_log(logfile); + logfile = NULL; + if (conf.logfile_given) + free(old_logfile_arg); + else if (conf.daemon_given) { /* re-use old logfile */ + conf.logfile_arg = old_logfile_arg; + conf.logfile_given = 1; + } + } + if (conf.logfile_given) { + logfile = open_log(conf.logfile_arg); + log_welcome(conf.loglevel_arg); + } + ret = dss_chdir(conf.dest_dir_arg); +out: + free(config_file); + if (ret >= 0) + return; + log_err_msg(EMERG, -ret); + exit(EXIT_FAILURE); +} + +void handle_sighup(void) +{ + DSS_NOTICE_LOG("SIGHUP\n"); + parse_config_file(1); } int rename_incomplete_snapshot(int64_t start) @@ -704,7 +793,7 @@ void compute_next_snapshot_time(struct snapshot_list *sl) tv_add(&now, &tmp, &next_snapshot_time); } -void handle_signal(struct snapshot_list *sl) +void handle_signal(void) { int sig, ret = next_signal(); @@ -722,6 +811,7 @@ void handle_signal(struct snapshot_list *sl) exit(EXIT_FAILURE); case SIGHUP: handle_sighup(); + ret = 1; break; case SIGCHLD: ret = reap_child(&pid, &status); @@ -732,9 +822,6 @@ void handle_signal(struct snapshot_list *sl) ret = handle_rsync_exit(status); else ret = handle_rm_exit(status); - free_snapshot_list(sl); - get_snapshot_list(sl); - compute_next_snapshot_time(sl); } out: if (ret < 0) @@ -820,14 +907,15 @@ int select_loop(void) struct timeval tv = {.tv_sec = 0, .tv_usec = 0}; struct snapshot_list sl = {.num_snapshots = 0}; - get_snapshot_list(&sl); - compute_next_snapshot_time(&sl); for (;;) { struct timeval now, *tvp = &tv; fd_set rfds; int low_disk_space; char **rsync_argv; + free_snapshot_list(&sl); + get_snapshot_list(&sl); + compute_next_snapshot_time(&sl); FD_ZERO(&rfds); FD_SET(signal_pipe, &rfds); if (rsync_pid) @@ -837,8 +925,10 @@ int select_loop(void) ret = dss_select(signal_pipe + 1, &rfds, NULL, tvp); if (ret < 0) return ret; - if (FD_ISSET(signal_pipe, &rfds)) - handle_signal(&sl); + if (FD_ISSET(signal_pipe, &rfds)) { + handle_signal(); + continue; + } if (rm_pid) continue; ret = disk_space_low(); @@ -978,61 +1068,6 @@ __noreturn void clean_exit(int status) free(dss_error_txt); exit(status); } - -int read_config_file(void) -{ - int ret; - char *config_file; - struct stat statbuf; - - if (conf.config_file_given) - config_file = dss_strdup(conf.config_file_arg); - else { - char *home = get_homedir(); - config_file = make_message("%s/.dssrc", home); - free(home); - } - ret = stat(config_file, &statbuf); - if (ret && conf.config_file_given) { - ret = -ERRNO_TO_DSS_ERROR(errno); - make_err_msg("failed to stat config file %s", config_file); - goto out; - } - if (!ret) { - struct cmdline_parser_params params = { - .override = 0, - .initialize = 0, - .check_required = 0, - .check_ambiguity = 0 - }; - cmdline_parser_config_file(config_file, &conf, ¶ms); - } - if (!conf.source_dir_given || !conf.dest_dir_given) { - ret = -E_SYNTAX; - make_err_msg("you need to specify both source_dir and dest_dir"); - goto out; - } - ret = 1; -out: - free(config_file); - return ret; -} - -int check_config(void) -{ - if (conf.unit_interval_arg <= 0) { - make_err_msg("bad unit interval: %i", conf.unit_interval_arg); - return -E_INVALID_NUMBER; - } - DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg); - if (conf.num_intervals_arg <= 0) { - make_err_msg("bad number of intervals %i", conf.num_intervals_arg); - return -E_INVALID_NUMBER; - } - DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg); - return 1; -} - static void setup_signal_handling(void) { int ret; @@ -1059,24 +1094,11 @@ int main(int argc, char **argv) int ret; cmdline_parser(argc, argv, &conf); /* aborts on errors */ - ret = read_config_file(); - if (ret < 0) - goto out; - ret = check_config(); - if (ret < 0) - goto out; - if (conf.logfile_given) { - logfile = open_log(conf.logfile_arg); - log_welcome(conf.loglevel_arg); - } - ret = dss_chdir(conf.dest_dir_arg); - if (ret < 0) - goto out; + parse_config_file(0); if (conf.daemon_given) daemon_init(); setup_signal_handling(); ret = call_command_handler(); -out: if (ret < 0) log_err_msg(EMERG, -ret); clean_exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE); diff --git a/dss.ggo b/dss.ggo index a0a3503..57e9313 100644 --- a/dss.ggo +++ b/dss.ggo @@ -21,6 +21,17 @@ details=" configuration file. As usual, if an option is given both at the command line and in the configuration file, the command line option takes precedence. + + However, there is an important exception to this rule: + If the --run option was given (see below) then dss honors + SIGHUP and re-reads its configuration file whenever it + receives this signal. In this case the options in the config + file override any options that were previously given at the + command line. This allows to change the configuration of a + running dss process on the fly by sending SIGHUP. + + Note that it is not possible to change whether dss runs as + background daemon by sending SIGHUP. " option "daemon" d