busybox/sysklogd/syslogd.c

/* vi: set sw=4 ts=4: */
/*
 * Mini syslogd implementation for busybox
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Copyright (C) 2000 by Karl M. Hegbloom <karlheg@debian.org>
 *
 * "circular buffer" Copyright (C) 2001 by Gennady Feldman <gfeldman@gena01.com>
 *
 * Maintainer: Gennady Feldman <gfeldman@gena01.com> as of Mar 12, 2001
 *
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 */

/*
 * Done in syslogd_and_logger.c:
#include "libbb.h"
#define SYSLOG_NAMES
#define SYSLOG_NAMES_CONST
#include <syslog.h>
*/

#include <paths.h>
#include <sys/un.h>
#include <sys/uio.h>

#if ENABLE_FEATURE_REMOTE_LOG
#include <netinet/in.h>
#endif

#if ENABLE_FEATURE_IPC_SYSLOG
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/shm.h>
#endif


#define DEBUG 0

/* MARK code is not very useful, is bloat, and broken:
 * can deadlock if alarmed to make MARK while writing to IPC buffer
 * (semaphores are down but do_mark routine tries to down them again) */
#undef SYSLOGD_MARK

enum {
	MAX_READ = 256,
	DNS_WAIT_SEC = 2 * 60,
};

/* Semaphore operation structures */
struct shbuf_ds {
	int32_t size;   /* size of data - 1 */
	int32_t tail;   /* end of message list */
	char data[1];   /* data/messages */
};

/* Allows us to have smaller initializer. Ugly. */
#define GLOBALS \
	const char *logFilePath;                \
	int logFD;                              \
	/* interval between marks in seconds */ \
	/*int markInterval;*/                   \
	/* level of messages to be logged */    \
	int logLevel;                           \
USE_FEATURE_ROTATE_LOGFILE( \
	/* max size of file before rotation */  \
	unsigned logFileSize;                   \
	/* number of rotated message files */   \
	unsigned logFileRotate;                 \
	unsigned curFileSize;                   \
	smallint isRegular;                     \
) \
USE_FEATURE_REMOTE_LOG( \
	/* udp socket for remote logging */     \
	int remoteFD;                           \
	len_and_sockaddr* remoteAddr;           \
) \
USE_FEATURE_IPC_SYSLOG( \
	int shmid; /* ipc shared memory id */   \
	int s_semid; /* ipc semaphore id */     \
	int shm_size;                           \
	struct sembuf SMwup[1];                 \
	struct sembuf SMwdn[3];                 \
)

struct init_globals {
	GLOBALS
};

struct globals {
	GLOBALS

#if ENABLE_FEATURE_REMOTE_LOG
	unsigned last_dns_resolve;
	char *remoteAddrStr;
#endif

#if ENABLE_FEATURE_IPC_SYSLOG
	struct shbuf_ds *shbuf;
#endif
	time_t last_log_time;
	/* localhost's name. We print only first 64 chars */
	char *hostname;

	/* We recv into recvbuf... */
	char recvbuf[MAX_READ * (1 + ENABLE_FEATURE_SYSLOGD_DUP)];
	/* ...then copy to parsebuf, escaping control chars */
	/* (can grow x2 max) */
	char parsebuf[MAX_READ*2];
	/* ...then sprintf into printbuf, adding timestamp (15 chars),
	 * host (64), fac.prio (20) to the message */
	/* (growth by: 15 + 64 + 20 + delims = ~110) */
	char printbuf[MAX_READ*2 + 128];
};

static const struct init_globals init_data = {
	.logFilePath = "/var/log/messages",
	.logFD = -1,
#ifdef SYSLOGD_MARK
	.markInterval = 20 * 60,
#endif
	.logLevel = 8,
#if ENABLE_FEATURE_ROTATE_LOGFILE
	.logFileSize = 200 * 1024,
	.logFileRotate = 1,
#endif
#if ENABLE_FEATURE_REMOTE_LOG
	.remoteFD = -1,
#endif
#if ENABLE_FEATURE_IPC_SYSLOG
	.shmid = -1,
	.s_semid = -1,
	.shm_size = ((CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE)*1024), // default shm size
	.SMwup = { {1, -1, IPC_NOWAIT} },
	.SMwdn = { {0, 0}, {1, 0}, {1, +1} },
#endif
};

#define G (*ptr_to_globals)
#define INIT_G() do { \
	SET_PTR_TO_GLOBALS(memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data))); \
} while (0)


/* Options */
enum {
	OPTBIT_mark = 0, // -m
	OPTBIT_nofork, // -n
	OPTBIT_outfile, // -O
	OPTBIT_loglevel, // -l
	OPTBIT_small, // -S
	USE_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize   ,)	// -s
	USE_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt  ,)	// -b
	USE_FEATURE_REMOTE_LOG(    OPTBIT_remote     ,)	// -R
	USE_FEATURE_REMOTE_LOG(    OPTBIT_locallog   ,)	// -L
	USE_FEATURE_IPC_SYSLOG(    OPTBIT_circularlog,)	// -C
	USE_FEATURE_SYSLOGD_DUP(   OPTBIT_dup        ,)	// -D

	OPT_mark        = 1 << OPTBIT_mark    ,
	OPT_nofork      = 1 << OPTBIT_nofork  ,
	OPT_outfile     = 1 << OPTBIT_outfile ,
	OPT_loglevel    = 1 << OPTBIT_loglevel,
	OPT_small       = 1 << OPTBIT_small   ,
	OPT_filesize    = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize   )) + 0,
	OPT_rotatecnt   = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt  )) + 0,
	OPT_remotelog   = USE_FEATURE_REMOTE_LOG(    (1 << OPTBIT_remote     )) + 0,
	OPT_locallog    = USE_FEATURE_REMOTE_LOG(    (1 << OPTBIT_locallog   )) + 0,
	OPT_circularlog = USE_FEATURE_IPC_SYSLOG(    (1 << OPTBIT_circularlog)) + 0,
	OPT_dup         = USE_FEATURE_SYSLOGD_DUP(   (1 << OPTBIT_dup        )) + 0,
};
#define OPTION_STR "m:nO:l:S" \
	USE_FEATURE_ROTATE_LOGFILE("s:" ) \
	USE_FEATURE_ROTATE_LOGFILE("b:" ) \
	USE_FEATURE_REMOTE_LOG(    "R:" ) \
	USE_FEATURE_REMOTE_LOG(    "L"  ) \
	USE_FEATURE_IPC_SYSLOG(    "C::") \
	USE_FEATURE_SYSLOGD_DUP(   "D"  )
#define OPTION_DECL *opt_m, *opt_l \
	USE_FEATURE_ROTATE_LOGFILE(,*opt_s) \
	USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \
	USE_FEATURE_IPC_SYSLOG(    ,*opt_C = NULL)
#define OPTION_PARAM &opt_m, &G.logFilePath, &opt_l \
	USE_FEATURE_ROTATE_LOGFILE(,&opt_s) \
	USE_FEATURE_ROTATE_LOGFILE(,&opt_b) \
	USE_FEATURE_REMOTE_LOG(    ,&G.remoteAddrStr) \
	USE_FEATURE_IPC_SYSLOG(    ,&opt_C)


/* circular buffer variables/structures */
#if ENABLE_FEATURE_IPC_SYSLOG

#if CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE < 4
#error Sorry, you must set the syslogd buffer size to at least 4KB.
#error Please check CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE
#endif

/* our shared key (syslogd.c and logread.c must be in sync) */
enum { KEY_ID = 0x414e4547 }; /* "GENA" */

static void ipcsyslog_cleanup(void)
{
	if (G.shmid != -1) {
		shmdt(G.shbuf);
	}
	if (G.shmid != -1) {
		shmctl(G.shmid, IPC_RMID, NULL);
	}
	if (G.s_semid != -1) {
		semctl(G.s_semid, 0, IPC_RMID, 0);
	}
}

static void ipcsyslog_init(void)
{
	if (DEBUG)
		printf("shmget(%x, %d,...)\n", (int)KEY_ID, G.shm_size);

	G.shmid = shmget(KEY_ID, G.shm_size, IPC_CREAT | 0644);
	if (G.shmid == -1) {
		bb_perror_msg_and_die("shmget");
	}

	G.shbuf = shmat(G.shmid, NULL, 0);
	if (G.shbuf == (void*) -1L) { /* shmat has bizarre error return */
		bb_perror_msg_and_die("shmat");
	}

	memset(G.shbuf, 0, G.shm_size);
	G.shbuf->size = G.shm_size - offsetof(struct shbuf_ds, data) - 1;
	/*G.shbuf->tail = 0;*/

	// we'll trust the OS to set initial semval to 0 (let's hope)
	G.s_semid = semget(KEY_ID, 2, IPC_CREAT | IPC_EXCL | 1023);
	if (G.s_semid == -1) {
		if (errno == EEXIST) {
			G.s_semid = semget(KEY_ID, 2, 0);
			if (G.s_semid != -1)
				return;
		}
		bb_perror_msg_and_die("semget");
	}
}

/* Write message to shared mem buffer */
static void log_to_shmem(const char *msg, int len)
{
	int old_tail, new_tail;

	if (semop(G.s_semid, G.SMwdn, 3) == -1) {
		bb_perror_msg_and_die("SMwdn");
	}

	/* Circular Buffer Algorithm:
	 * --------------------------
	 * tail == position where to store next syslog message.
	 * tail's max value is (shbuf->size - 1)
	 * Last byte of buffer is never used and remains NUL.
	 */
	len++; /* length with NUL included */
 again:
	old_tail = G.shbuf->tail;
	new_tail = old_tail + len;
	if (new_tail < G.shbuf->size) {
		/* store message, set new tail */
		memcpy(G.shbuf->data + old_tail, msg, len);
		G.shbuf->tail = new_tail;
	} else {
		/* k == available buffer space ahead of old tail */
		int k = G.shbuf->size - old_tail;
		/* copy what fits to the end of buffer, and repeat */
		memcpy(G.shbuf->data + old_tail, msg, k);
		msg += k;
		len -= k;
		G.shbuf->tail = 0;
		goto again;
	}
	if (semop(G.s_semid, G.SMwup, 1) == -1) {
		bb_perror_msg_and_die("SMwup");
	}
	if (DEBUG)
		printf("tail:%d\n", G.shbuf->tail);
}
#else
void ipcsyslog_cleanup(void);
void ipcsyslog_init(void);
void log_to_shmem(const char *msg);
#endif /* FEATURE_IPC_SYSLOG */


/* Print a message to the log file. */
static void log_locally(time_t now, char *msg)
{
	struct flock fl;
	int len = strlen(msg);

#if ENABLE_FEATURE_IPC_SYSLOG
	if ((option_mask32 & OPT_circularlog) && G.shbuf) {
		log_to_shmem(msg, len);
		return;
	}
#endif
	if (G.logFD >= 0) {
		/* Reopen log file every second. This allows admin
		 * to delete the file and not worry about restarting us.
		 * This costs almost nothing since it happens
		 * _at most_ once a second.
		 */
		if (!now)
			now = time(NULL);
		if (G.last_log_time != now) {
			G.last_log_time = now;
			close(G.logFD);
			goto reopen;
		}
	} else {
 reopen:
		G.logFD = open(G.logFilePath, O_WRONLY | O_CREAT
					| O_NOCTTY | O_APPEND | O_NONBLOCK,
					0666);
		if (G.logFD < 0) {
			/* cannot open logfile? - print to /dev/console then */
			int fd = device_open(DEV_CONSOLE, O_WRONLY | O_NOCTTY | O_NONBLOCK);
			if (fd < 0)
				fd = 2; /* then stderr, dammit */
			full_write(fd, msg, len);
			if (fd != 2)
				close(fd);
			return;
		}
#if ENABLE_FEATURE_ROTATE_LOGFILE
		{
			struct stat statf;
			G.isRegular = (fstat(G.logFD, &statf) == 0 && S_ISREG(statf.st_mode));
			/* bug (mostly harmless): can wrap around if file > 4gb */
			G.curFileSize = statf.st_size;
		}
#endif
	}

	fl.l_whence = SEEK_SET;
	fl.l_start = 0;
	fl.l_len = 1;
	fl.l_type = F_WRLCK;
	fcntl(G.logFD, F_SETLKW, &fl);

#if ENABLE_FEATURE_ROTATE_LOGFILE
	if (G.logFileSize && G.isRegular && G.curFileSize > G.logFileSize) {
		if (G.logFileRotate) { /* always 0..99 */
			int i = strlen(G.logFilePath) + 3 + 1;
			char oldFile[i];
			char newFile[i];
			i = G.logFileRotate - 1;
			/* rename: f.8 -> f.9; f.7 -> f.8; ... */
			while (1) {
				sprintf(newFile, "%s.%d", G.logFilePath, i);
				if (i == 0) break;
				sprintf(oldFile, "%s.%d", G.logFilePath, --i);
				/* ignore errors - file might be missing */
				rename(oldFile, newFile);
			}
			/* newFile == "f.0" now */
			rename(G.logFilePath, newFile);
			fl.l_type = F_UNLCK;
			fcntl(G.logFD, F_SETLKW, &fl);
			close(G.logFD);
			goto reopen;
		}
		ftruncate(G.logFD, 0);
	}
	G.curFileSize +=
#endif
			full_write(G.logFD, msg, len);
	fl.l_type = F_UNLCK;
	fcntl(G.logFD, F_SETLKW, &fl);
}

static void parse_fac_prio_20(int pri, char *res20)
{
	const CODE *c_pri, *c_fac;

	if (pri != 0) {
		c_fac = facilitynames;
		while (c_fac->c_name) {
			if (c_fac->c_val != (LOG_FAC(pri) << 3)) {
				c_fac++;
				continue;
			}
			/* facility is found, look for prio */
			c_pri = prioritynames;
			while (c_pri->c_name) {
				if (c_pri->c_val != LOG_PRI(pri)) {
					c_pri++;
					continue;
				}
				snprintf(res20, 20, "%s.%s",
						c_fac->c_name, c_pri->c_name);
				return;
			}
			/* prio not found, bail out */
			break;
		}
		snprintf(res20, 20, "<%d>", pri);
	}
}

/* len parameter is used only for "is there a timestamp?" check.
 * NB: some callers cheat and supply len==0 when they know
 * that there is no timestamp, short-circuiting the test. */
static void timestamp_and_log(int pri, char *msg, int len)
{
	char *timestamp;
	time_t now;

	if (len < 16 || msg[3] != ' ' || msg[6] != ' '
	 || msg[9] != ':' || msg[12] != ':' || msg[15] != ' '
	) {
		time(&now);
		timestamp = ctime(&now) + 4; /* skip day of week */
	} else {
		now = 0;
		timestamp = msg;
		msg += 16;
	}
	timestamp[15] = '\0';

	if (option_mask32 & OPT_small)
		sprintf(G.printbuf, "%s %s\n", timestamp, msg);
	else {
		char res[20];
		parse_fac_prio_20(pri, res);
		sprintf(G.printbuf, "%s %.64s %s %s\n", timestamp, G.hostname, res, msg);
	}

	/* Log message locally (to file or shared mem) */
	log_locally(now, G.printbuf);
}

static void timestamp_and_log_internal(const char *msg)
{
	if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_locallog))
		return;
	timestamp_and_log(LOG_SYSLOG | LOG_INFO, (char*)msg, 0);
}

/* tmpbuf[len] is a NUL byte (set by caller), but there can be other,
 * embedded NULs. Split messages on each of these NULs, parse prio,
 * escape control chars and log each locally. */
static void split_escape_and_log(char *tmpbuf, int len)
{
	char *p = tmpbuf;

	tmpbuf += len;
	while (p < tmpbuf) {
		char c;
		char *q = G.parsebuf;
		int pri = (LOG_USER | LOG_NOTICE);

		if (*p == '<') {
			/* Parse the magic priority number */
			pri = bb_strtou(p + 1, &p, 10);
			if (*p == '>')
				p++;
			if (pri & ~(LOG_FACMASK | LOG_PRIMASK))
				pri = (LOG_USER | LOG_NOTICE);
		}

		while ((c = *p++)) {
			if (c == '\n')
				c = ' ';
			if (!(c & ~0x1f) && c != '\t') {
				*q++ = '^';
				c += '@'; /* ^@, ^A, ^B... */
			}
			*q++ = c;
		}
		*q = '\0';

		/* Now log it */
		if (LOG_PRI(pri) < G.logLevel)
			timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
	}
}

static void quit_signal(int sig)
{
	timestamp_and_log_internal("syslogd exiting");
	puts("syslogd exiting");
	if (ENABLE_FEATURE_IPC_SYSLOG)
		ipcsyslog_cleanup();
	kill_myself_with_sig(sig);
}

#ifdef SYSLOGD_MARK
static void do_mark(int sig)
{
	if (G.markInterval) {
		timestamp_and_log_internal("-- MARK --");
		alarm(G.markInterval);
	}
}
#endif

/* Don't inline: prevent struct sockaddr_un to take up space on stack
 * permanently */
static NOINLINE int create_socket(void)
{
	struct sockaddr_un sunx;
	int sock_fd;
	char *dev_log_name;

	memset(&sunx, 0, sizeof(sunx));
	sunx.sun_family = AF_UNIX;

	/* Unlink old /dev/log or object it points to. */
	/* (if it exists, bind will fail) */
	strcpy(sunx.sun_path, "/dev/log");
	dev_log_name = xmalloc_follow_symlinks("/dev/log");
	if (dev_log_name) {
		safe_strncpy(sunx.sun_path, dev_log_name, sizeof(sunx.sun_path));
		free(dev_log_name);
	}
	unlink(sunx.sun_path);

	sock_fd = xsocket(AF_UNIX, SOCK_DGRAM, 0);
	xbind(sock_fd, (struct sockaddr *) &sunx, sizeof(sunx));
	chmod("/dev/log", 0666);

	return sock_fd;
}

#if ENABLE_FEATURE_REMOTE_LOG
static int try_to_resolve_remote(void)
{
	if (!G.remoteAddr) {
		unsigned now = monotonic_sec();

		/* Don't resolve name too often - DNS timeouts can be big */
		if ((now - G.last_dns_resolve) < DNS_WAIT_SEC)
			return -1;
		G.last_dns_resolve = now;
		G.remoteAddr = host2sockaddr(G.remoteAddrStr, 514);
		if (!G.remoteAddr)
			return -1;
	}
	return socket(G.remoteAddr->u.sa.sa_family, SOCK_DGRAM, 0);
}
#endif

static void do_syslogd(void) NORETURN;
static void do_syslogd(void)
{
	int sock_fd;
#if ENABLE_FEATURE_SYSLOGD_DUP
	int last_sz = -1;
	char *last_buf;
	char *recvbuf = G.recvbuf;
#else
#define recvbuf (G.recvbuf)
#endif

	/* Set up signal handlers */
	bb_signals(0
		+ (1 << SIGINT)
		+ (1 << SIGTERM)
		+ (1 << SIGQUIT)
		, quit_signal);
	signal(SIGHUP, SIG_IGN);
	/* signal(SIGCHLD, SIG_IGN); - why? */
#ifdef SYSLOGD_MARK
	signal(SIGALRM, do_mark);
	alarm(G.markInterval);
#endif
	sock_fd = create_socket();

	if (ENABLE_FEATURE_IPC_SYSLOG && (option_mask32 & OPT_circularlog)) {
		ipcsyslog_init();
	}

	timestamp_and_log_internal("syslogd started: BusyBox v" BB_VER);

	for (;;) {
		ssize_t sz;

#if ENABLE_FEATURE_SYSLOGD_DUP
		last_buf = recvbuf;
		if (recvbuf == G.recvbuf)
			recvbuf = G.recvbuf + MAX_READ;
		else
			recvbuf = G.recvbuf;
#endif
 read_again:
		sz = safe_read(sock_fd, recvbuf, MAX_READ - 1);
		if (sz < 0)
			bb_perror_msg_and_die("read from /dev/log");

		/* Drop trailing '\n' and NULs (typically there is one NUL) */
		while (1) {
			if (sz == 0)
				goto read_again;
			/* man 3 syslog says: "A trailing newline is added when needed".
			 * However, neither glibc nor uclibc do this:
			 * syslog(prio, "test")   sends "test\0" to /dev/log,
			 * syslog(prio, "test\n") sends "test\n\0".
			 * IOW: newline is passed verbatim!
			 * I take it to mean that it's syslogd's job
			 * to make those look identical in the log files. */
			if (recvbuf[sz-1] != '\0' && recvbuf[sz-1] != '\n')
				break;
			sz--;
		}
#if ENABLE_FEATURE_SYSLOGD_DUP
		if ((option_mask32 & OPT_dup) && (sz == last_sz))
			if (memcmp(last_buf, recvbuf, sz) == 0)
				continue;
		last_sz = sz;
#endif
#if ENABLE_FEATURE_REMOTE_LOG
		/* We are not modifying log messages in any way before send */
		/* Remote site cannot trust _us_ anyway and need to do validation again */
		if (G.remoteAddrStr) {
			if (-1 == G.remoteFD) {
				G.remoteFD = try_to_resolve_remote();
				if (-1 == G.remoteFD)
					goto no_luck;
			}
			/* Stock syslogd sends it '\n'-terminated
			 * over network, mimic that */
			recvbuf[sz] = '\n';
			/* send message to remote logger, ignore possible error */
			/* TODO: on some errors, close and set G.remoteFD to -1
			 * so that DNS resolution and connect is retried? */
			sendto(G.remoteFD, recvbuf, sz+1, MSG_DONTWAIT,
				    &G.remoteAddr->u.sa, G.remoteAddr->len);
 no_luck: ;
		}
#endif
		if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) {
			recvbuf[sz] = '\0'; /* ensure it *is* NUL terminated */
			split_escape_and_log(recvbuf, sz);
		}
	} /* for (;;) */
#undef recvbuf
}

int syslogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int syslogd_main(int argc UNUSED_PARAM, char **argv)
{
	char OPTION_DECL;

	INIT_G();
#if ENABLE_FEATURE_REMOTE_LOG
	G.last_dns_resolve = monotonic_sec() - DNS_WAIT_SEC - 1;
#endif

	/* do normal option parsing */
	opt_complementary = "=0"; /* no non-option params */
	getopt32(argv, OPTION_STR, OPTION_PARAM);
#ifdef SYSLOGD_MARK
	if (option_mask32 & OPT_mark) // -m
		G.markInterval = xatou_range(opt_m, 0, INT_MAX/60) * 60;
#endif
	//if (option_mask32 & OPT_nofork) // -n
	//if (option_mask32 & OPT_outfile) // -O
	if (option_mask32 & OPT_loglevel) // -l
		G.logLevel = xatou_range(opt_l, 1, 8);
	//if (option_mask32 & OPT_small) // -S
#if ENABLE_FEATURE_ROTATE_LOGFILE
	if (option_mask32 & OPT_filesize) // -s
		G.logFileSize = xatou_range(opt_s, 0, INT_MAX/1024) * 1024;
	if (option_mask32 & OPT_rotatecnt) // -b
		G.logFileRotate = xatou_range(opt_b, 0, 99);
#endif
#if ENABLE_FEATURE_IPC_SYSLOG
	if (opt_C) // -Cn
		G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;
#endif

	/* If they have not specified remote logging, then log locally */
	if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_remotelog))
		option_mask32 |= OPT_locallog;

	/* Store away localhost's name before the fork */
	G.hostname = safe_gethostname();
	*strchrnul(G.hostname, '.') = '\0';

	if (!(option_mask32 & OPT_nofork)) {
		bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
	}
	umask(0);
	write_pidfile("/var/run/syslogd.pid");
	do_syslogd();
	/* return EXIT_SUCCESS; */
}

/* Clean up. Needed because we are included from syslogd_and_logger.c */
#undef G
#undef GLOBALS
#undef INIT_G
#undef OPTION_STR
#undef OPTION_DECL
#undef OPTION_PARAM
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Mini syslogd implementation for busybox
4	*
5	* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
6	*
7	* Copyright (C) 2000 by Karl M. Hegbloom <karlheg@debian.org>
8	*
9	* "circular buffer" Copyright (C) 2001 by Gennady Feldman <gfeldman@gena01.com>
10	*
11	* Maintainer: Gennady Feldman <gfeldman@gena01.com> as of Mar 12, 2001
12	*
13	* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
14	*/
15
16	/*
17	* Done in syslogd_and_logger.c:
18	#include "libbb.h"
19	#define SYSLOG_NAMES
20	#define SYSLOG_NAMES_CONST
21	#include <syslog.h>
22	*/
23
24	#include <paths.h>
25	#include <sys/un.h>
26	#include <sys/uio.h>
27
28	#if ENABLE_FEATURE_REMOTE_LOG
29	#include <netinet/in.h>
30	#endif
31
32	#if ENABLE_FEATURE_IPC_SYSLOG
33	#include <sys/ipc.h>
34	#include <sys/sem.h>
35	#include <sys/shm.h>
36	#endif
37
38
39	#define DEBUG 0
40
41	/* MARK code is not very useful, is bloat, and broken:
42	* can deadlock if alarmed to make MARK while writing to IPC buffer
43	* (semaphores are down but do_mark routine tries to down them again) */
44	#undef SYSLOGD_MARK
45
46	enum {
47	MAX_READ = 256,
48	DNS_WAIT_SEC = 2 * 60,
49	};
50
51	/* Semaphore operation structures */
52	struct shbuf_ds {
53	int32_t size; /* size of data - 1 */
54	int32_t tail; /* end of message list */
55	char data[1]; /* data/messages */
56	};
57
58	/* Allows us to have smaller initializer. Ugly. */
59	#define GLOBALS \
60	const char *logFilePath; \
61	int logFD; \
62	/* interval between marks in seconds */ \
63	/int markInterval;/ \
64	/* level of messages to be logged */ \
65	int logLevel; \
66	USE_FEATURE_ROTATE_LOGFILE( \
67	/* max size of file before rotation */ \
68	unsigned logFileSize; \
69	/* number of rotated message files */ \
70	unsigned logFileRotate; \
71	unsigned curFileSize; \
72	smallint isRegular; \
73	) \
74	USE_FEATURE_REMOTE_LOG( \
75	/* udp socket for remote logging */ \
76	int remoteFD; \
77	len_and_sockaddr* remoteAddr; \
78	) \
79	USE_FEATURE_IPC_SYSLOG( \
80	int shmid; /* ipc shared memory id */ \
81	int s_semid; /* ipc semaphore id */ \
82	int shm_size; \
83	struct sembuf SMwup[1]; \
84	struct sembuf SMwdn[3]; \
85	)
86
87	struct init_globals {
88	GLOBALS
89	};
90
91	struct globals {
92	GLOBALS
93
94	#if ENABLE_FEATURE_REMOTE_LOG
95	unsigned last_dns_resolve;
96	char *remoteAddrStr;
97	#endif
98
99	#if ENABLE_FEATURE_IPC_SYSLOG
100	struct shbuf_ds *shbuf;
101	#endif
102	time_t last_log_time;
103	/* localhost's name. We print only first 64 chars */
104	char *hostname;
105
106	/* We recv into recvbuf... */
107	char recvbuf[MAX_READ * (1 + ENABLE_FEATURE_SYSLOGD_DUP)];
108	/* ...then copy to parsebuf, escaping control chars */
109	/* (can grow x2 max) */
110	char parsebuf[MAX_READ*2];
111	/* ...then sprintf into printbuf, adding timestamp (15 chars),
112	* host (64), fac.prio (20) to the message */
113	/* (growth by: 15 + 64 + 20 + delims = ~110) */
114	char printbuf[MAX_READ*2 + 128];
115	};
116
117	static const struct init_globals init_data = {
118	.logFilePath = "/var/log/messages",
119	.logFD = -1,
120	#ifdef SYSLOGD_MARK
121	.markInterval = 20 * 60,
122	#endif
123	.logLevel = 8,
124	#if ENABLE_FEATURE_ROTATE_LOGFILE
125	.logFileSize = 200 * 1024,
126	.logFileRotate = 1,
127	#endif
128	#if ENABLE_FEATURE_REMOTE_LOG
129	.remoteFD = -1,
130	#endif
131	#if ENABLE_FEATURE_IPC_SYSLOG
132	.shmid = -1,
133	.s_semid = -1,
134	.shm_size = ((CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE)*1024), // default shm size
135	.SMwup = { {1, -1, IPC_NOWAIT} },
136	.SMwdn = { {0, 0}, {1, 0}, {1, +1} },
137	#endif
138	};
139
140	#define G (*ptr_to_globals)
141	#define INIT_G() do { \
142	SET_PTR_TO_GLOBALS(memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data))); \
143	} while (0)
144
145
146	/* Options */
147	enum {
148	OPTBIT_mark = 0, // -m
149	OPTBIT_nofork, // -n
150	OPTBIT_outfile, // -O
151	OPTBIT_loglevel, // -l
152	OPTBIT_small, // -S
153	USE_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize ,) // -s
154	USE_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt ,) // -b
155	USE_FEATURE_REMOTE_LOG( OPTBIT_remote ,) // -R
156	USE_FEATURE_REMOTE_LOG( OPTBIT_locallog ,) // -L
157	USE_FEATURE_IPC_SYSLOG( OPTBIT_circularlog,) // -C
158	USE_FEATURE_SYSLOGD_DUP( OPTBIT_dup ,) // -D
159
160	OPT_mark = 1 << OPTBIT_mark ,
161	OPT_nofork = 1 << OPTBIT_nofork ,
162	OPT_outfile = 1 << OPTBIT_outfile ,
163	OPT_loglevel = 1 << OPTBIT_loglevel,
164	OPT_small = 1 << OPTBIT_small ,
165	OPT_filesize = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize )) + 0,
166	OPT_rotatecnt = USE_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt )) + 0,
167	OPT_remotelog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_remote )) + 0,
168	OPT_locallog = USE_FEATURE_REMOTE_LOG( (1 << OPTBIT_locallog )) + 0,
169	OPT_circularlog = USE_FEATURE_IPC_SYSLOG( (1 << OPTBIT_circularlog)) + 0,
170	OPT_dup = USE_FEATURE_SYSLOGD_DUP( (1 << OPTBIT_dup )) + 0,
171	};
172	#define OPTION_STR "m:nO:l:S" \
173	USE_FEATURE_ROTATE_LOGFILE("s:" ) \
174	USE_FEATURE_ROTATE_LOGFILE("b:" ) \
175	USE_FEATURE_REMOTE_LOG( "R:" ) \
176	USE_FEATURE_REMOTE_LOG( "L" ) \
177	USE_FEATURE_IPC_SYSLOG( "C::") \
178	USE_FEATURE_SYSLOGD_DUP( "D" )
179	#define OPTION_DECL opt_m, opt_l \
180	USE_FEATURE_ROTATE_LOGFILE(,*opt_s) \
181	USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \
182	USE_FEATURE_IPC_SYSLOG( ,*opt_C = NULL)
183	#define OPTION_PARAM &opt_m, &G.logFilePath, &opt_l \
184	USE_FEATURE_ROTATE_LOGFILE(,&opt_s) \
185	USE_FEATURE_ROTATE_LOGFILE(,&opt_b) \
186	USE_FEATURE_REMOTE_LOG( ,&G.remoteAddrStr) \
187	USE_FEATURE_IPC_SYSLOG( ,&opt_C)
188
189
190	/* circular buffer variables/structures */
191	#if ENABLE_FEATURE_IPC_SYSLOG
192
193	#if CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE < 4
194	#error Sorry, you must set the syslogd buffer size to at least 4KB.
195	#error Please check CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE
196	#endif
197
198	/* our shared key (syslogd.c and logread.c must be in sync) */
199	enum { KEY_ID = 0x414e4547 }; /* "GENA" */
200
201	static void ipcsyslog_cleanup(void)
202	{
203	if (G.shmid != -1) {
204	shmdt(G.shbuf);
205	}
206	if (G.shmid != -1) {
207	shmctl(G.shmid, IPC_RMID, NULL);
208	}
209	if (G.s_semid != -1) {
210	semctl(G.s_semid, 0, IPC_RMID, 0);
211	}
212	}
213
214	static void ipcsyslog_init(void)
215	{
216	if (DEBUG)
217	printf("shmget(%x, %d,...)\n", (int)KEY_ID, G.shm_size);
218
219	G.shmid = shmget(KEY_ID, G.shm_size, IPC_CREAT \| 0644);
220	if (G.shmid == -1) {
221	bb_perror_msg_and_die("shmget");
222	}
223
224	G.shbuf = shmat(G.shmid, NULL, 0);
225	if (G.shbuf == (void) -1L) { / shmat has bizarre error return */
226	bb_perror_msg_and_die("shmat");
227	}
228
229	memset(G.shbuf, 0, G.shm_size);
230	G.shbuf->size = G.shm_size - offsetof(struct shbuf_ds, data) - 1;
231	/G.shbuf->tail = 0;/
232
233	// we'll trust the OS to set initial semval to 0 (let's hope)
234	G.s_semid = semget(KEY_ID, 2, IPC_CREAT \| IPC_EXCL \| 1023);
235	if (G.s_semid == -1) {
236	if (errno == EEXIST) {
237	G.s_semid = semget(KEY_ID, 2, 0);
238	if (G.s_semid != -1)
239	return;
240	}
241	bb_perror_msg_and_die("semget");
242	}
243	}
244
245	/* Write message to shared mem buffer */
246	static void log_to_shmem(const char *msg, int len)
247	{
248	int old_tail, new_tail;
249
250	if (semop(G.s_semid, G.SMwdn, 3) == -1) {
251	bb_perror_msg_and_die("SMwdn");
252	}
253
254	/* Circular Buffer Algorithm:
255	* --------------------------
256	* tail == position where to store next syslog message.
257	* tail's max value is (shbuf->size - 1)
258	* Last byte of buffer is never used and remains NUL.
259	*/
260	len++; /* length with NUL included */
261	again:
262	old_tail = G.shbuf->tail;
263	new_tail = old_tail + len;
264	if (new_tail < G.shbuf->size) {
265	/* store message, set new tail */
266	memcpy(G.shbuf->data + old_tail, msg, len);
267	G.shbuf->tail = new_tail;
268	} else {
269	/* k == available buffer space ahead of old tail */
270	int k = G.shbuf->size - old_tail;
271	/* copy what fits to the end of buffer, and repeat */
272	memcpy(G.shbuf->data + old_tail, msg, k);
273	msg += k;
274	len -= k;
275	G.shbuf->tail = 0;
276	goto again;
277	}
278	if (semop(G.s_semid, G.SMwup, 1) == -1) {
279	bb_perror_msg_and_die("SMwup");
280	}
281	if (DEBUG)
282	printf("tail:%d\n", G.shbuf->tail);
283	}
284	#else
285	void ipcsyslog_cleanup(void);
286	void ipcsyslog_init(void);
287	void log_to_shmem(const char *msg);
288	#endif /* FEATURE_IPC_SYSLOG */
289
290
291	/* Print a message to the log file. */
292	static void log_locally(time_t now, char *msg)
293	{
294	struct flock fl;
295	int len = strlen(msg);
296
297	#if ENABLE_FEATURE_IPC_SYSLOG
298	if ((option_mask32 & OPT_circularlog) && G.shbuf) {
299	log_to_shmem(msg, len);
300	return;
301	}
302	#endif
303	if (G.logFD >= 0) {
304	/* Reopen log file every second. This allows admin
305	* to delete the file and not worry about restarting us.
306	* This costs almost nothing since it happens
307	* _at most_ once a second.
308	*/
309	if (!now)
310	now = time(NULL);
311	if (G.last_log_time != now) {
312	G.last_log_time = now;
313	close(G.logFD);
314	goto reopen;
315	}
316	} else {
317	reopen:
318	G.logFD = open(G.logFilePath, O_WRONLY \| O_CREAT
319	\| O_NOCTTY \| O_APPEND \| O_NONBLOCK,
320	0666);
321	if (G.logFD < 0) {
322	/* cannot open logfile? - print to /dev/console then */
323	int fd = device_open(DEV_CONSOLE, O_WRONLY \| O_NOCTTY \| O_NONBLOCK);
324	if (fd < 0)
325	fd = 2; /* then stderr, dammit */
326	full_write(fd, msg, len);
327	if (fd != 2)
328	close(fd);
329	return;
330	}
331	#if ENABLE_FEATURE_ROTATE_LOGFILE
332	{
333	struct stat statf;
334	G.isRegular = (fstat(G.logFD, &statf) == 0 && S_ISREG(statf.st_mode));
335	/* bug (mostly harmless): can wrap around if file > 4gb */
336	G.curFileSize = statf.st_size;
337	}
338	#endif
339	}
340
341	fl.l_whence = SEEK_SET;
342	fl.l_start = 0;
343	fl.l_len = 1;
344	fl.l_type = F_WRLCK;
345	fcntl(G.logFD, F_SETLKW, &fl);
346
347	#if ENABLE_FEATURE_ROTATE_LOGFILE
348	if (G.logFileSize && G.isRegular && G.curFileSize > G.logFileSize) {
349	if (G.logFileRotate) { /* always 0..99 */
350	int i = strlen(G.logFilePath) + 3 + 1;
351	char oldFile[i];
352	char newFile[i];
353	i = G.logFileRotate - 1;
354	/* rename: f.8 -> f.9; f.7 -> f.8; ... */
355	while (1) {
356	sprintf(newFile, "%s.%d", G.logFilePath, i);
357	if (i == 0) break;
358	sprintf(oldFile, "%s.%d", G.logFilePath, --i);
359	/* ignore errors - file might be missing */
360	rename(oldFile, newFile);
361	}
362	/* newFile == "f.0" now */
363	rename(G.logFilePath, newFile);
364	fl.l_type = F_UNLCK;
365	fcntl(G.logFD, F_SETLKW, &fl);
366	close(G.logFD);
367	goto reopen;
368	}
369	ftruncate(G.logFD, 0);
370	}
371	G.curFileSize +=
372	#endif
373	full_write(G.logFD, msg, len);
374	fl.l_type = F_UNLCK;
375	fcntl(G.logFD, F_SETLKW, &fl);
376	}
377
378	static void parse_fac_prio_20(int pri, char *res20)
379	{
380	const CODE c_pri, c_fac;
381
382	if (pri != 0) {
383	c_fac = facilitynames;
384	while (c_fac->c_name) {
385	if (c_fac->c_val != (LOG_FAC(pri) << 3)) {
386	c_fac++;
387	continue;
388	}
389	/* facility is found, look for prio */
390	c_pri = prioritynames;
391	while (c_pri->c_name) {
392	if (c_pri->c_val != LOG_PRI(pri)) {
393	c_pri++;
394	continue;
395	}
396	snprintf(res20, 20, "%s.%s",
397	c_fac->c_name, c_pri->c_name);
398	return;
399	}
400	/* prio not found, bail out */
401	break;
402	}
403	snprintf(res20, 20, "<%d>", pri);
404	}
405	}
406
407	/* len parameter is used only for "is there a timestamp?" check.
408	* NB: some callers cheat and supply len==0 when they know
409	* that there is no timestamp, short-circuiting the test. */
410	static void timestamp_and_log(int pri, char *msg, int len)
411	{
412	char *timestamp;
413	time_t now;
414
415	if (len < 16 \|\| msg[3] != ' ' \|\| msg[6] != ' '
416	\|\| msg[9] != ':' \|\| msg[12] != ':' \|\| msg[15] != ' '
417	) {
418	time(&now);
419	timestamp = ctime(&now) + 4; /* skip day of week */
420	} else {
421	now = 0;
422	timestamp = msg;
423	msg += 16;
424	}
425	timestamp[15] = '\0';
426
427	if (option_mask32 & OPT_small)
428	sprintf(G.printbuf, "%s %s\n", timestamp, msg);
429	else {
430	char res[20];
431	parse_fac_prio_20(pri, res);
432	sprintf(G.printbuf, "%s %.64s %s %s\n", timestamp, G.hostname, res, msg);
433	}
434
435	/* Log message locally (to file or shared mem) */
436	log_locally(now, G.printbuf);
437	}
438
439	static void timestamp_and_log_internal(const char *msg)
440	{
441	if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_locallog))
442	return;
443	timestamp_and_log(LOG_SYSLOG \| LOG_INFO, (char*)msg, 0);
444	}
445
446	/* tmpbuf[len] is a NUL byte (set by caller), but there can be other,
447	* embedded NULs. Split messages on each of these NULs, parse prio,
448	* escape control chars and log each locally. */
449	static void split_escape_and_log(char *tmpbuf, int len)
450	{
451	char *p = tmpbuf;
452
453	tmpbuf += len;
454	while (p < tmpbuf) {
455	char c;
456	char *q = G.parsebuf;
457	int pri = (LOG_USER \| LOG_NOTICE);
458
459	if (*p == '<') {
460	/* Parse the magic priority number */
461	pri = bb_strtou(p + 1, &p, 10);
462	if (*p == '>')
463	p++;
464	if (pri & ~(LOG_FACMASK \| LOG_PRIMASK))
465	pri = (LOG_USER \| LOG_NOTICE);
466	}
467
468	while ((c = *p++)) {
469	if (c == '\n')
470	c = ' ';
471	if (!(c & ~0x1f) && c != '\t') {
472	*q++ = '^';
473	c += '@'; /* ^@, ^A, ^B... */
474	}
475	*q++ = c;
476	}
477	*q = '\0';
478
479	/* Now log it */
480	if (LOG_PRI(pri) < G.logLevel)
481	timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
482	}
483	}
484
485	static void quit_signal(int sig)
486	{
487	timestamp_and_log_internal("syslogd exiting");
488	puts("syslogd exiting");
489	if (ENABLE_FEATURE_IPC_SYSLOG)
490	ipcsyslog_cleanup();
491	kill_myself_with_sig(sig);
492	}
493
494	#ifdef SYSLOGD_MARK
495	static void do_mark(int sig)
496	{
497	if (G.markInterval) {
498	timestamp_and_log_internal("-- MARK --");
499	alarm(G.markInterval);
500	}
501	}
502	#endif
503
504	/* Don't inline: prevent struct sockaddr_un to take up space on stack
505	* permanently */
506	static NOINLINE int create_socket(void)
507	{
508	struct sockaddr_un sunx;
509	int sock_fd;
510	char *dev_log_name;
511
512	memset(&sunx, 0, sizeof(sunx));
513	sunx.sun_family = AF_UNIX;
514
515	/* Unlink old /dev/log or object it points to. */
516	/* (if it exists, bind will fail) */
517	strcpy(sunx.sun_path, "/dev/log");
518	dev_log_name = xmalloc_follow_symlinks("/dev/log");
519	if (dev_log_name) {
520	safe_strncpy(sunx.sun_path, dev_log_name, sizeof(sunx.sun_path));
521	free(dev_log_name);
522	}
523	unlink(sunx.sun_path);
524
525	sock_fd = xsocket(AF_UNIX, SOCK_DGRAM, 0);
526	xbind(sock_fd, (struct sockaddr *) &sunx, sizeof(sunx));
527	chmod("/dev/log", 0666);
528
529	return sock_fd;
530	}
531
532	#if ENABLE_FEATURE_REMOTE_LOG
533	static int try_to_resolve_remote(void)
534	{
535	if (!G.remoteAddr) {
536	unsigned now = monotonic_sec();
537
538	/* Don't resolve name too often - DNS timeouts can be big */
539	if ((now - G.last_dns_resolve) < DNS_WAIT_SEC)
540	return -1;
541	G.last_dns_resolve = now;
542	G.remoteAddr = host2sockaddr(G.remoteAddrStr, 514);
543	if (!G.remoteAddr)
544	return -1;
545	}
546	return socket(G.remoteAddr->u.sa.sa_family, SOCK_DGRAM, 0);
547	}
548	#endif
549
550	static void do_syslogd(void) NORETURN;
551	static void do_syslogd(void)
552	{
553	int sock_fd;
554	#if ENABLE_FEATURE_SYSLOGD_DUP
555	int last_sz = -1;
556	char *last_buf;
557	char *recvbuf = G.recvbuf;
558	#else
559	#define recvbuf (G.recvbuf)
560	#endif
561
562	/* Set up signal handlers */
563	bb_signals(0
564	+ (1 << SIGINT)
565	+ (1 << SIGTERM)
566	+ (1 << SIGQUIT)
567	, quit_signal);
568	signal(SIGHUP, SIG_IGN);
569	/* signal(SIGCHLD, SIG_IGN); - why? */
570	#ifdef SYSLOGD_MARK
571	signal(SIGALRM, do_mark);
572	alarm(G.markInterval);
573	#endif
574	sock_fd = create_socket();
575
576	if (ENABLE_FEATURE_IPC_SYSLOG && (option_mask32 & OPT_circularlog)) {
577	ipcsyslog_init();
578	}
579
580	timestamp_and_log_internal("syslogd started: BusyBox v" BB_VER);
581
582	for (;;) {
583	ssize_t sz;
584
585	#if ENABLE_FEATURE_SYSLOGD_DUP
586	last_buf = recvbuf;
587	if (recvbuf == G.recvbuf)
588	recvbuf = G.recvbuf + MAX_READ;
589	else
590	recvbuf = G.recvbuf;
591	#endif
592	read_again:
593	sz = safe_read(sock_fd, recvbuf, MAX_READ - 1);
594	if (sz < 0)
595	bb_perror_msg_and_die("read from /dev/log");
596
597	/* Drop trailing '\n' and NULs (typically there is one NUL) */
598	while (1) {
599	if (sz == 0)
600	goto read_again;
601	/* man 3 syslog says: "A trailing newline is added when needed".
602	* However, neither glibc nor uclibc do this:
603	* syslog(prio, "test") sends "test\0" to /dev/log,
604	* syslog(prio, "test\n") sends "test\n\0".
605	* IOW: newline is passed verbatim!
606	* I take it to mean that it's syslogd's job
607	* to make those look identical in the log files. */
608	if (recvbuf[sz-1] != '\0' && recvbuf[sz-1] != '\n')
609	break;
610	sz--;
611	}
612	#if ENABLE_FEATURE_SYSLOGD_DUP
613	if ((option_mask32 & OPT_dup) && (sz == last_sz))
614	if (memcmp(last_buf, recvbuf, sz) == 0)
615	continue;
616	last_sz = sz;
617	#endif
618	#if ENABLE_FEATURE_REMOTE_LOG
619	/* We are not modifying log messages in any way before send */
620	/* Remote site cannot trust _us_ anyway and need to do validation again */
621	if (G.remoteAddrStr) {
622	if (-1 == G.remoteFD) {
623	G.remoteFD = try_to_resolve_remote();
624	if (-1 == G.remoteFD)
625	goto no_luck;
626	}
627	/* Stock syslogd sends it '\n'-terminated
628	* over network, mimic that */
629	recvbuf[sz] = '\n';
630	/* send message to remote logger, ignore possible error */
631	/* TODO: on some errors, close and set G.remoteFD to -1
632	* so that DNS resolution and connect is retried? */
633	sendto(G.remoteFD, recvbuf, sz+1, MSG_DONTWAIT,
634	&G.remoteAddr->u.sa, G.remoteAddr->len);
635	no_luck: ;
636	}
637	#endif
638	if (!ENABLE_FEATURE_REMOTE_LOG \|\| (option_mask32 & OPT_locallog)) {
639	recvbuf[sz] = '\0'; /* ensure it is NUL terminated */
640	split_escape_and_log(recvbuf, sz);
641	}
642	} /* for (;;) */
643	#undef recvbuf
644	}
645
646	int syslogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
647	int syslogd_main(int argc UNUSED_PARAM, char **argv)
648	{
649	char OPTION_DECL;
650
651	INIT_G();
652	#if ENABLE_FEATURE_REMOTE_LOG
653	G.last_dns_resolve = monotonic_sec() - DNS_WAIT_SEC - 1;
654	#endif
655
656	/* do normal option parsing */
657	opt_complementary = "=0"; /* no non-option params */
658	getopt32(argv, OPTION_STR, OPTION_PARAM);
659	#ifdef SYSLOGD_MARK
660	if (option_mask32 & OPT_mark) // -m
661	G.markInterval = xatou_range(opt_m, 0, INT_MAX/60) * 60;
662	#endif
663	//if (option_mask32 & OPT_nofork) // -n
664	//if (option_mask32 & OPT_outfile) // -O
665	if (option_mask32 & OPT_loglevel) // -l
666	G.logLevel = xatou_range(opt_l, 1, 8);
667	//if (option_mask32 & OPT_small) // -S
668	#if ENABLE_FEATURE_ROTATE_LOGFILE
669	if (option_mask32 & OPT_filesize) // -s
670	G.logFileSize = xatou_range(opt_s, 0, INT_MAX/1024) * 1024;
671	if (option_mask32 & OPT_rotatecnt) // -b
672	G.logFileRotate = xatou_range(opt_b, 0, 99);
673	#endif
674	#if ENABLE_FEATURE_IPC_SYSLOG
675	if (opt_C) // -Cn
676	G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;
677	#endif
678
679	/* If they have not specified remote logging, then log locally */
680	if (ENABLE_FEATURE_REMOTE_LOG && !(option_mask32 & OPT_remotelog))
681	option_mask32 \|= OPT_locallog;
682
683	/* Store away localhost's name before the fork */
684	G.hostname = safe_gethostname();
685	*strchrnul(G.hostname, '.') = '\0';
686
687	if (!(option_mask32 & OPT_nofork)) {
688	bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
689	}
690	umask(0);
691	write_pidfile("/var/run/syslogd.pid");
692	do_syslogd();
693	/* return EXIT_SUCCESS; */
694	}
695
696	/* Clean up. Needed because we are included from syslogd_and_logger.c */
697	#undef G
698	#undef GLOBALS
699	#undef INIT_G
700	#undef OPTION_STR
701	#undef OPTION_DECL
702	#undef OPTION_PARAM