X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=daemon.c;h=7c625bbea9d84c5ac9b37a22253346576cbb7183;hp=a669482fc27525f8c9d2c4ce64a62eb350d4cb06;hb=c998e827328c7989986e4fb91048e7f427f722a8;hpb=a694ab16b6ff43b545ccd530360b7224433a5b76 diff --git a/daemon.c b/daemon.c index a669482f..7c625bbe 100644 --- a/daemon.c +++ b/daemon.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1997-2009 Andre Noll + * Copyright (C) 1997 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -10,8 +10,8 @@ #include #include /* getgrnam() */ #include -#include -#include +#include +#include #include "para.h" #include "daemon.h" @@ -26,7 +26,6 @@ struct daemon { char *logfile_name; /** Current loglevel, see \ref daemon_set_loglevel(). */ int loglevel; - /** Used by \ref server_uptime() and \ref uptime_str(). */ time_t startuptime; /** The file pointer if the logfile is open. */ @@ -39,12 +38,7 @@ struct daemon { static struct daemon the_daemon, *me = &the_daemon; -/** - * Activate default log colors. - * - * This should be called early if color support is wanted. - */ -void daemon_set_default_log_colors(void) +static void daemon_set_default_log_colors(void) { int i; static const char *default_log_colors[NUM_LOGLEVELS] = { @@ -56,22 +50,16 @@ void daemon_set_default_log_colors(void) [LL_CRIT] = "magenta bold", [LL_EMERG] = "red bold", }; - for (i = 0; i < NUM_LOGLEVELS; i++) { - int ret = color_parse(default_log_colors[i], me->log_colors[i]); - assert(ret >= 0); - } + for (i = 0; i < NUM_LOGLEVELS; i++) + color_parse_or_die(default_log_colors[i], me->log_colors[i]); } /** * Set the color for one loglevel. * - * \param arg The loglevel/color specifier. - * - * \a arg must be of the form "ll:[fg [bg]] [attr]". - * - * \return 1 On success, -1 on errors. + * \param arg Must be of the form "ll:[fg [bg]] [attr]". */ -int daemon_set_log_color(char const *arg) +void daemon_set_log_color_or_die(const char *arg) { char *p = strchr(arg, ':'); int ret, ll; @@ -83,14 +71,45 @@ int daemon_set_log_color(char const *arg) goto err; ll = ret; p++; - ret = color_parse(p, me->log_colors[ll]); - if (ret < 0) - goto err; - return 1; + color_parse_or_die(p, me->log_colors[ll]); + return; err: - PARA_ERROR_LOG("%s: color syntax error\n", arg); - return -1; + PARA_EMERG_LOG("%s: invalid color argument\n", arg); + exit(EXIT_FAILURE); +} +/** + * Initialize color mode if necessary. + * + * \param color_arg The argument given to --color. + * \param color_arg_auto The value for automatic color detection. + * \param color_arg_no The value to disable colored log messages. + * \param logfile_given In auto mode colors are disabled if this value is true. + * + * If color_arg equals color_arg_no, color mode is disabled. That is, calls to + * para_log() will not produce colored output. If color_arg equals + * color_arg_auto, the function detects automatically whether to activate + * colors. Otherwise color mode is enabled. + * + * If color mode is to be enabled, the default colors are set for each + * loglevel. They can be overwritten by calling daemon_set_log_color_or_die(). + * + * \return Whether colors have been enabled by the function. + */ +bool daemon_init_colors_or_die(int color_arg, int color_arg_auto, + int color_arg_no, bool logfile_given) +{ + if (color_arg == color_arg_no) + return false; + if (color_arg == color_arg_auto) { + if (logfile_given) + return false; + if (!isatty(STDERR_FILENO)) + return false; + } + daemon_set_flag(DF_COLOR_LOG); + daemon_set_default_log_colors(); + return true; } /** @@ -98,7 +117,7 @@ err: * * \param logfile_name The full path of the logfile. */ -void daemon_set_logfile(char *logfile_name) +void daemon_set_logfile(const char *logfile_name) { free(me->logfile_name); me->logfile_name = NULL; @@ -111,7 +130,7 @@ void daemon_set_logfile(char *logfile_name) * * \param loglevel The smallest level that should be logged. */ -void daemon_set_loglevel(char *loglevel) +void daemon_set_loglevel(const char *loglevel) { int ret = get_loglevel_by_name(loglevel); @@ -131,31 +150,30 @@ void daemon_set_flag(unsigned flag) me->flags |= flag; } -/** - * Clear one of the daemon config flags. - * - * \param flag The flag to clear. - * - * \sa \ref daemon_flags. - */ -void daemon_clear_flag(unsigned flag) +static bool daemon_test_flag(unsigned flag) { - me->flags &= ~flag; + return me->flags & flag; } -static bool daemon_test_flag(unsigned flag) +static void dummy_sighandler(__a_unused int s) { - return me->flags & flag; } /** * Do the usual stuff to become a daemon. * - * Fork, become session leader, dup fd 0, 1, 2 to /dev/null. + * \param parent_waits Whether the parent process should pause before exit. * - * \sa fork(2), setsid(2), dup(2). + * Fork, become session leader, cd to /, and dup fd 0, 1, 2 to /dev/null. If \a + * parent_waits is false, the parent process terminates immediately. + * Otherwise, it calls pause() to sleep until it receives \p SIGTERM or \p + * SIGCHLD and exits successfully thereafter. This behaviour is useful if the + * daemon process should not detach from the console until the child process + * has completed its setup. + * + * \sa fork(2), setsid(2), dup(2), pause(2). */ -void daemonize(void) +void daemonize(bool parent_waits) { pid_t pid; int null; @@ -164,14 +182,20 @@ void daemonize(void) pid = fork(); if (pid < 0) goto err; - if (pid) + if (pid) { + if (parent_waits) { + signal(SIGTERM, dummy_sighandler); + signal(SIGCHLD, dummy_sighandler); + pause(); + } exit(EXIT_SUCCESS); /* parent exits */ + } /* become session leader */ if (setsid() < 0) goto err; if (chdir("/") < 0) goto err; - null = open("/dev/null", O_RDONLY); + null = open("/dev/null", O_RDWR); if (null < 0) goto err; if (dup2(null, STDIN_FILENO) < 0) @@ -215,16 +239,36 @@ void daemon_open_log_or_die(void) strerror(errno)); exit(EXIT_FAILURE); } - setlinebuf(me->logfile); + /* equivalent to setlinebuf(), but portable */ + setvbuf(me->logfile, NULL, _IOLBF, 0); } /** * Log the startup message containing the paraslash version. + * + * \param name The name of the executable. + * + * First the given \a name is prefixed with the string "para_". Next the git + * version is appended. The resulting string is logged with priority "INFO". */ -void log_welcome(const char *whoami) +void daemon_log_welcome(const char *name) { - PARA_INFO_LOG("welcome to %s " PACKAGE_VERSION " ("BUILD_DATE")\n", - whoami); + PARA_INFO_LOG("welcome to para_%s-" PACKAGE_VERSION " \n", name); +} + +/** + * Renice the calling process. + * + * \param prio The priority value to set. + * + * Errors are not considered fatal, but a warning message is logged if the + * underlying call to setpriority(2) fails. + */ +void daemon_set_priority(int prio) +{ + if (setpriority(PRIO_PROCESS, 0, prio) < 0) + PARA_WARNING_LOG("could not set priority to %d: %s\n", prio, + strerror(errno)); } /** @@ -241,7 +285,7 @@ void log_welcome(const char *whoami) * * \sa getpwnam(3), getuid(2), setuid(2), getgrnam(2), setgid(2) */ -void drop_privileges_or_die(const char *username, const char *groupname) +void daemon_drop_privileges_or_die(const char *username, const char *groupname) { struct passwd *p; char *tmp; @@ -282,43 +326,52 @@ void drop_privileges_or_die(const char *username, const char *groupname) } /** - * Set/get the server uptime. + * Set the startup time. * - * \param set_or_get Chose one of the two modes. + * This should be called once on startup. It sets the start time to the + * current time. The stored time is used for retrieving the server uptime. * - * This should be called at startup time with \a set_or_get equal to \p - * UPTIME_SET which sets the uptime to zero. Subsequent calls with \a - * set_or_get equal to \p UPTIME_GET return the uptime. + * \sa time(2), \ref daemon_get_uptime(), \ref daemon_get_uptime_str(). + */ +void daemon_set_start_time(void) +{ + time(&me->startuptime); +} - * \return Zero if called with \a set_or_get equal to \p UPTIME_SET, the number - * of seconds elapsed since the last reset otherwise. +/** + * Get the uptime. + * + * \param current_time The current time. * - * \sa time(2), difftime(3). + * The \a current_time pointer may be \p NULL. In this case the function + * obtains the current time from the system. + * + * \return This returns the server uptime in seconds, i.e. the difference + * between the current time and the value stored previously via \ref + * daemon_set_start_time(). */ -time_t server_uptime(enum uptime set_or_get) +time_t daemon_get_uptime(const struct timeval *current_time) { - time_t now; - double diff; + time_t t; - if (set_or_get == UPTIME_SET) { - time(&me->startuptime); - return 0; - } - time(&now); - diff = difftime(now, me->startuptime); - return (time_t) diff; + if (current_time) + return current_time->tv_sec - me->startuptime; + time(&t); + return difftime(t, me->startuptime); } /** - * Construct string containing uptime. + * Construct a string containing the current uptime. + * + * \param current_time See a \ref daemon_get_uptime(). * * \return A dynamically allocated string of the form "days:hours:minutes". * * \sa server_uptime. */ -__malloc char *uptime_str(void) +__malloc char *daemon_get_uptime_str(const struct timeval *current_time) { - long t = server_uptime(UPTIME_GET); + long t = daemon_get_uptime(current_time); return make_message("%li:%02li:%02li", t / 86400, (t / 3600) % 24, (t / 60) % 60); } @@ -329,7 +382,7 @@ __malloc char *uptime_str(void) * \param ll The log level. * \param fmt The format string describing the log message. */ -__printf_2_3 void para_log(int ll, const char* fmt,...) +__printf_2_3 void daemon_log(int ll, const char* fmt,...) { va_list argp; FILE *fp; @@ -349,7 +402,7 @@ __printf_2_3 void para_log(int ll, const char* fmt,...) fprintf(fp, "%s", color); if (log_time || log_timing) { struct timeval tv; - gettimeofday(&tv, NULL); + clock_get_realtime(&tv); if (daemon_test_flag(DF_LOG_TIME)) { /* print date and time */ time_t t1 = tv.tv_sec; char str[100];