/*
- * Copyright (C) 1997-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 1997-2008 Andre Noll <maan@systemlinux.org>
*
* 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 <pwd.h>
#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);
}
/**
- * 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)
{
}
/**
- * 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
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)
{
}
/**
- * 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);
}