X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=daemon.c;h=bb75478adae6f639b314fa7aa98a7ad2c3501e72;hp=46eb8f19196acfe37f280eb6650223437acdbf1b;hb=98e61f7563ae284e058ce6251b89626ab6254ff7;hpb=10aa048801a707c80776f606d50a3bbb7c4a9192;ds=inline diff --git a/daemon.c b/daemon.c index 46eb8f19..bb75478a 100644 --- a/daemon.c +++ b/daemon.c @@ -1,22 +1,10 @@ /* - * Copyright (C) 1997-2006 Andre Noll + * Copyright (C) 1997-2008 Andre Noll * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. + * Licensed under the GPL v2. For licencing details see COPYING. */ -/** \file daemon.c some helpers for programs that detach from the console */ +/** \file daemon.c Some helpers for programs that detach from the console. */ #include "para.h" #include "daemon.h" #include @@ -28,53 +16,61 @@ #include "string.h" /** - * 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. * - * \sa fork(2), setsid(2), dup(2) + * \sa fork(2), setsid(2), dup(2). */ void daemon_init(void) { pid_t pid; int null; - 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) + PARA_INFO_LOG("daemonizing\n"); + pid = fork(); + if (pid < 0) + goto err; + if (pid) exit(EXIT_SUCCESS); /* parent exits */ - /* child */ - setsid(); /* become session leader */ - chdir("/"); + /* become session leader */ + if (setsid() < 0) + goto err; + if (chdir("/") < 0) + goto err; umask(0); - null = open("/dev/null", O_RDONLY); 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; +err: + PARA_EMERG_LOG("fatal: %s\n", strerror(errno)); + exit(EXIT_FAILURE); } /** - * fopen() a file in append mode + * fopen() the given file in append mode. * - * \param logfile_name the name of the file to open + * \param logfile_name The name of the file to open. * - * Either calls exit() or returns a valid file handle. + * \return Either calls exit() or returns a valid file handle. */ FILE *open_log(const char *logfile_name) { FILE *logfile; - if (!logfile_name) - return NULL; - if (!(logfile = fopen(logfile_name, "a"))) { - PARA_EMERG_LOG("can not open %s, uid: %d\n", logfile_name, - getuid()); + assert(logfile_name); + logfile = fopen(logfile_name, "a"); + if (!logfile) { + PARA_EMERG_LOG("can not open %s: %s\n", logfile_name, + strerror(errno)); exit(EXIT_FAILURE); } setlinebuf(logfile); @@ -82,22 +78,22 @@ FILE *open_log(const char *logfile_name) } /** - * close the log file of the daemon + * Close the log file of the daemon. * - * \param logfile the log file handle + * \param logfile The log file handle. * - * It's OK to call this with logfile == NULL + * It's OK to call this with logfile == \p NULL. */ void close_log(FILE* logfile) { if (!logfile) return; - PARA_INFO_LOG("%s", "closing logfile\n"); + PARA_INFO_LOG("closing logfile\n"); fclose(logfile); } /** - * log the startup message containing the paraslash version + * Log the startup message containing the paraslash version. */ void log_welcome(const char *whoami, int loglevel) { @@ -107,10 +103,10 @@ void log_welcome(const char *whoami, int loglevel) } /** - * 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 @@ -130,66 +126,71 @@ 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("%s", "dropping root privileges\n"); + PARA_INFO_LOG("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/get the server uptime + * Set/get the server uptime. * - * \param set_or_get chose one of the two modes + * \param set_or_get Chose one of the two modes. * * 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. + * set_or_get equal to \p UPTIME_GET return the uptime. + + * \return Zero if called with \a set_or_get equal to \p UPTIME_SET, the number + * of seconds ellapsed since the last reset otherwise. * - * \sa time(2), difftime(3) + * \sa time(2), difftime(3). */ time_t server_uptime(enum uptime set_or_get) { static time_t startuptime; time_t now; + double diff; if (set_or_get == UPTIME_SET) { time(&startuptime); return 0; } time(&now); - return (time_t) difftime(now, startuptime); + diff = difftime(now, startuptime); + return (time_t) diff; } /** - * construct string containing uptime + * Construct string containing uptime. * - * The format of the returned string is "days:hours:minutes" + * \return A dynamically allocated string of the form "days:hours:minutes". * - * \sa server_uptime + * \sa server_uptime. */ __malloc char *uptime_str(void) { - time_t t = server_uptime(UPTIME_GET); + long t = server_uptime(UPTIME_GET); return make_message("%li:%02li:%02li", t / 86400, (t / 3600) % 24, (t / 60) % 60); }