X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=daemon.c;h=e47639bc42864cc4881d5992bb567e902f4752ac;hb=349d14071d64971a86d2af092cb09ccbc4989afb;hp=666b0a5c645cbc0f34b3347a3e021355a6444193;hpb=471684761a2039bbc89aa1e3c33c62de6bef86cf;p=paraslash.git diff --git a/daemon.c b/daemon.c index 666b0a5c..e47639bc 100644 --- a/daemon.c +++ b/daemon.c @@ -1,104 +1,285 @@ -/* - * Copyright (C) 1997-2006 Andre Noll - * - * Licensed under the GPL v2. For licencing details see COPYING. - */ +/* Copyright (C) 1997 Andre Noll , see file COPYING. */ -/** \file daemon.c some helpers for programs that detach from the console */ -#include "para.h" -#include "daemon.h" -#include +/** \file daemon.c Some helpers for programs that detach from the console. */ -/* getgrnam() */ -#include +#include +#include +#include /* getgrnam() */ #include +#include +#include +#include "para.h" +#include "daemon.h" #include "string.h" +#include "color.h" + +/** The internal state of the daemon. */ +struct daemon { + /** See \ref daemon_flags. */ + unsigned flags; + /** Set by \ref daemon_set_logfile(). */ + 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. */ + FILE *logfile; + /** Used by para_log() if \p DF_LOG_HOSTNAME is set. */ + char *hostname; + /** Used for colored log messages. */ + char log_colors[NUM_LOGLEVELS][COLOR_MAXLEN]; +}; + +static struct daemon the_daemon, *me = &the_daemon; + +static void daemon_set_default_log_colors(void) +{ + int i; + static const char *default_log_colors[NUM_LOGLEVELS] = { + [LL_DEBUG] = "normal", + [LL_INFO] = "normal", + [LL_NOTICE] = "normal", + [LL_WARNING] = "yellow", + [LL_ERROR] = "red", + [LL_CRIT] = "magenta bold", + [LL_EMERG] = "red bold", + }; + 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 Must be of the form "ll:[fg [bg]] [attr]". + */ +void daemon_set_log_color_or_die(const char *arg) +{ + char *p = strchr(arg, ':'); + int ret, ll; + + if (!p) + goto err; + ret = get_loglevel_by_name(arg); + if (ret < 0) + goto err; + ll = ret; + p++; + color_parse_or_die(p, me->log_colors[ll]); + return; +err: + 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(const char *logfile_name) +{ + free(me->logfile_name); + me->logfile_name = NULL; + if (logfile_name) + me->logfile_name = para_strdup(logfile_name); +} + +/** + * Suppress log messages with severity lower than the given loglevel. + * + * \param loglevel The smallest level that should be logged. + */ +void daemon_set_loglevel(const char *loglevel) +{ + int ret = get_loglevel_by_name(loglevel); + + assert(ret >= 0); + me->loglevel = ret; +} + +/** + * Set one of the daemon config flags. + * + * \param flag The flag to set. + * + * \sa \ref daemon_flags. + */ +void daemon_set_flag(unsigned flag) +{ + me->flags |= flag; +} + +static bool daemon_test_flag(unsigned flag) +{ + return me->flags & flag; +} /** - * do the usual stuff to become a daemon + * 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, a pipe is created prior to the fork() and the parent tries to + * read a single byte from the reading end of the pipe. The child is supposed + * to write to the writing end of the pipe after it completed its setup + * procedure successfully. This behaviour is useful to let the parent process + * die with an error if the child process aborts early, since in this case the + * read() will return non-positive. + * + * \return This function either succeeds or calls exit(3). If parent_waits is + * true, the return value is the file descriptor of the writing end of the + * pipe. Otherwise the function returns zero. + * + * \sa fork(2), setsid(2), dup(2), pause(2). */ -void daemon_init(void) +int daemonize(bool parent_waits) { pid_t pid; - int null; + int null, pipe_fd[2]; - PARA_INFO_LOG("%s", "daemonizing\n"); - if ((pid = fork()) < 0) { - PARA_EMERG_LOG("%s", "failed to init daemon\n"); - exit(EXIT_FAILURE); - } else if (pid) - exit(EXIT_SUCCESS); /* parent exits */ - /* child */ - setsid(); /* become session leader */ - chdir("/"); - umask(0); - - null = open("/dev/null", O_RDONLY); + if (parent_waits && pipe(pipe_fd) < 0) + goto err; + PARA_INFO_LOG("subsequent log messages go to %s\n", me->logfile_name? + me->logfile_name : "/dev/null"); + pid = fork(); + if (pid < 0) + goto err; + if (pid) { /* parent exits */ + if (parent_waits) { + char c; + close(pipe_fd[1]); + exit(read(pipe_fd[0], &c, 1) <= 0? + EXIT_FAILURE : EXIT_SUCCESS); + } + exit(EXIT_SUCCESS); + } + if (parent_waits) + close(pipe_fd[0]); + /* become session leader */ + if (setsid() < 0) + goto err; + if (chdir("/") < 0) + goto err; + null = open("/dev/null", O_RDWR); if (null < 0) - exit(EXIT_FAILURE); - dup2(null, STDIN_FILENO); - dup2(null, STDOUT_FILENO); - dup2(null, STDERR_FILENO); + goto err; + if (dup2(null, STDIN_FILENO) < 0) + goto err; + if (dup2(null, STDOUT_FILENO) < 0) + goto err; + if (dup2(null, STDERR_FILENO) < 0) + goto err; close(null); + return parent_waits? pipe_fd[1] : 0; +err: + PARA_EMERG_LOG("fatal: %s\n", strerror(errno)); + exit(EXIT_FAILURE); } /** - * fopen() a file in append mode - * - * \param logfile_name the name of the file to open - * - * Either calls exit() or returns a valid file handle. + * Close the log file of the daemon. */ -FILE *open_log(const char *logfile_name) +void daemon_close_log(void) { - FILE *logfile; + if (!me->logfile) + return; + PARA_INFO_LOG("closing logfile\n"); + fclose(me->logfile); + me->logfile = NULL; +} - if (!logfile_name) - return NULL; - if (!(logfile = fopen(logfile_name, "a"))) { - PARA_EMERG_LOG("can not open %s, uid: %d\n", logfile_name, - getuid()); +/** + * fopen() the logfile in append mode. + * + * \return Either succeeds or exits. + */ +void daemon_open_log_or_die(void) +{ + daemon_close_log(); + if (!me->logfile_name) + return; + me->logfile = fopen(me->logfile_name, "a"); + if (!me->logfile) { + PARA_EMERG_LOG("can not open %s: %s\n", me->logfile_name, + strerror(errno)); exit(EXIT_FAILURE); } - setlinebuf(logfile); - return logfile; + /* equivalent to setlinebuf(), but portable */ + setvbuf(me->logfile, NULL, _IOLBF, 0); } /** - * close the log file of the daemon + * Log the startup message containing the paraslash version. * - * \param logfile the log file handle + * \param name The name of the executable. * - * It's OK to call this with logfile == NULL + * 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 close_log(FILE* logfile) +void daemon_log_welcome(const char *name) { - if (!logfile) - return; - PARA_INFO_LOG("%s", "closing logfile\n"); - fclose(logfile); + PARA_INFO_LOG("welcome to para_%s-" PACKAGE_VERSION " \n", name); } /** - * log the startup message containing the paraslash version + * 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 log_welcome(const char *whoami, int loglevel) +void daemon_set_priority(int prio) { - PARA_INFO_LOG("welcome to %s " PACKAGE_VERSION " ("BUILD_DATE")\n", - whoami); - PARA_DEBUG_LOG("using loglevel %d\n", loglevel); + if (setpriority(PRIO_PROCESS, 0, prio) < 0) + PARA_WARNING_LOG("could not set priority to %d: %s\n", prio, + strerror(errno)); } /** - * give up superuser privileges + * Give up superuser privileges. * - * \param username the user to switch to - * \param groupname the group to switch to + * \param username The user to switch to. + * \param groupname The group to switch to. * * This function returns immediately if not invoked with EUID zero. Otherwise, * it tries to obtain the GID of \a groupname and the UID of \a username. On @@ -108,7 +289,7 @@ void log_welcome(const char *whoami, int loglevel) * * \sa getpwnam(3), getuid(2), setuid(2), getgrnam(2), setgid(2) */ -void para_drop_privileges(const char *username, const char *groupname) +void daemon_drop_privileges_or_die(const char *username, const char *groupname) { struct passwd *p; char *tmp; @@ -118,68 +299,136 @@ void para_drop_privileges(const char *username, const char *groupname) if (groupname) { struct group *g = getgrnam(groupname); if (!g) { - PARA_EMERG_LOG("failed to get group %s\n", groupname); + PARA_EMERG_LOG("failed to get group %s: %s\n", + groupname, strerror(errno)); exit(EXIT_FAILURE); } if (setgid(g->gr_gid) < 0) { - PARA_EMERG_LOG("failed to set group id %d (%s)\n", - g->gr_gid, strerror(errno)); + PARA_EMERG_LOG("failed to set group id %d: %s\n", + (int)g->gr_gid, strerror(errno)); exit(EXIT_FAILURE); } } if (!username) { - PARA_EMERG_LOG("%s", "root privileges, but no user option given\n"); + PARA_EMERG_LOG("root privileges, but no user option given\n"); exit(EXIT_FAILURE); } tmp = para_strdup(username); p = getpwnam(tmp); free(tmp); if (!p) { - PARA_EMERG_LOG("%s", "no such user\n"); + PARA_EMERG_LOG("%s: no such user\n", username); + exit(EXIT_FAILURE); + } + PARA_INFO_LOG("dropping root privileges\n"); + if (setuid(p->pw_uid) < 0) { + PARA_EMERG_LOG("failed to set effective user ID (%s)", + strerror(errno)); exit(EXIT_FAILURE); } - PARA_INFO_LOG("%s", "dropping root privileges\n"); - setuid(p->pw_uid); - PARA_DEBUG_LOG("uid: %d, euid: %d\n", getuid(), geteuid()); + PARA_DEBUG_LOG("uid: %d, euid: %d\n", (int)getuid(), (int)geteuid()); +} + +/** + * Set the startup 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), \ref daemon_get_uptime(), \ref daemon_get_uptime_str(). + */ +void daemon_set_start_time(void) +{ + time(&me->startuptime); } /** - * set/get the server uptime + * Get the uptime. * - * \param set_or_get chose one of the two modes + * \param current_time The current time. * - * 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 number of seconds ellapsed - * since the last reset. + * The \a current_time pointer may be \p NULL. In this case the function + * obtains the current time from the system. * - * \sa time(2), difftime(3) + * \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) { - static time_t startuptime; - time_t now; - double diff; + time_t t; - if (set_or_get == UPTIME_SET) { - time(&startuptime); - return 0; - } - time(&now); - diff = difftime(now, 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. * - * The format of the returned string is "days:hours:minutes" + * \param current_time See a \ref daemon_get_uptime(). * - * \sa server_uptime + * \return A dynamically allocated string of the form "days:hours:minutes". */ -__malloc char *uptime_str(void) +__malloc char *daemon_get_uptime_str(const struct timeval *current_time) { - time_t 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); } + +/** + * The log function for para_server and para_audiod. + * + * \param ll The log level. + * \param fmt The format string describing the log message. + */ +__printf_2_3 void daemon_log(int ll, const char* fmt,...) +{ + va_list argp; + FILE *fp; + struct tm *tm; + char *color; + bool log_time = daemon_test_flag(DF_LOG_TIME), log_timing = + daemon_test_flag(DF_LOG_TIMING); + + ll = PARA_MIN(ll, NUM_LOGLEVELS - 1); + ll = PARA_MAX(ll, LL_DEBUG); + if (ll < me->loglevel) + return; + + fp = me->logfile? me->logfile : stderr; + color = daemon_test_flag(DF_COLOR_LOG)? me->log_colors[ll] : NULL; + if (color) + fprintf(fp, "%s", color); + if (log_time || log_timing) { + struct timeval tv; + clock_get_realtime(&tv); + if (daemon_test_flag(DF_LOG_TIME)) { /* print date and time */ + time_t t1 = tv.tv_sec; + char str[100]; + tm = localtime(&t1); + strftime(str, sizeof(str), "%b %d %H:%M:%S", tm); + fprintf(fp, "%s%s", str, log_timing? ":" : " "); + } + if (log_timing) /* print milliseconds */ + fprintf(fp, "%04lu ", (long unsigned)tv.tv_usec / 1000); + } + if (daemon_test_flag(DF_LOG_HOSTNAME)) { + if (!me->hostname) + me->hostname = para_hostname(); + fprintf(fp, "%s ", me->hostname); + } + if (daemon_test_flag(DF_LOG_LL)) /* log loglevel */ + fprintf(fp, "(%d) ", ll); + if (daemon_test_flag(DF_LOG_PID)) { /* log pid */ + pid_t mypid = getpid(); + fprintf(fp, "(%d) ", (int)mypid); + } + va_start(argp, fmt); + vfprintf(fp, fmt, argp); + va_end(argp); + if (color) + fprintf(fp, "%s", COLOR_RESET); +}