X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=daemon.c;h=7c625bbea9d84c5ac9b37a22253346576cbb7183;hp=ffdec4e35f3e8cdbd113a780f6d6ade7faf9fcfe;hb=33692c33f2effa9620064aec44c6196a8d830d05;hpb=b307a25ed895caa33684302b502e9e0e70dc78b7 diff --git a/daemon.c b/daemon.c index ffdec4e3..7c625bbe 100644 --- a/daemon.c +++ b/daemon.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1997-2011 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" @@ -38,12 +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] = { @@ -62,13 +57,9 @@ void daemon_set_default_log_colors(void) /** * 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]". */ -void daemon_set_log_color_or_die(char const *arg) +void daemon_set_log_color_or_die(const char *arg) { char *p = strchr(arg, ':'); int ret, ll; @@ -83,16 +74,50 @@ void daemon_set_log_color_or_die(char const *arg) color_parse_or_die(p, me->log_colors[ll]); return; err: - PARA_EMERG_LOG("%s: color syntax error\n", arg); + 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; +} + /** * Init or change the name of the log file. * * \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; @@ -105,7 +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); @@ -125,31 +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; @@ -158,14 +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) @@ -209,16 +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)); } /** @@ -235,7 +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; @@ -276,27 +326,20 @@ void drop_privileges_or_die(const char *username, const char *groupname) } /** - * Set the server startup time. - * - * \param startuptime The value to store as the server start time. + * Set the startup time. * - * This should be called once on startup with \a startuptime either NULL or a - * pointer to a struct timeval which contains the current time. If \a - * startuptime is NULL, the server start time is set to the current time. + * 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. * - * \sa time(2), difftime(3) \ref get_server_uptime(), \ref - * get_server_uptime_str(). + * \sa time(2), \ref daemon_get_uptime(), \ref daemon_get_uptime_str(). */ -void set_server_start_time(const struct timeval *startuptime) +void daemon_set_start_time(void) { - if (startuptime) - me->startuptime = startuptime->tv_sec; - else - time(&me->startuptime); + time(&me->startuptime); } /** - * Get the server uptime. + * Get the uptime. * * \param current_time The current time. * @@ -305,9 +348,9 @@ void set_server_start_time(const struct timeval *startuptime) * * \return This returns the server uptime in seconds, i.e. the difference * between the current time and the value stored previously via \ref - * set_server_start_time(). + * daemon_set_start_time(). */ -time_t get_server_uptime(const struct timeval *current_time) +time_t daemon_get_uptime(const struct timeval *current_time) { time_t t; @@ -320,15 +363,15 @@ time_t get_server_uptime(const struct timeval *current_time) /** * Construct a string containing the current uptime. * - * \param current_time See a \ref get_server_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 *get_server_uptime_str(const struct timeval *current_time) +__malloc char *daemon_get_uptime_str(const struct timeval *current_time) { - long t = get_server_uptime(current_time); + long t = daemon_get_uptime(current_time); return make_message("%li:%02li:%02li", t / 86400, (t / 3600) % 24, (t / 60) % 60); } @@ -339,7 +382,7 @@ __malloc char *get_server_uptime_str(const struct timeval *current_time) * \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; @@ -359,7 +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];