[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/sysklogd/syslogd.c b/ap/app/busybox/src/sysklogd/syslogd.c
new file mode 100644
index 0000000..3fe3f53
--- /dev/null
+++ b/ap/app/busybox/src/sysklogd/syslogd.c
@@ -0,0 +1,1059 @@
+/* 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 GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//usage:#define syslogd_trivial_usage
+//usage:       "[OPTIONS]"
+//usage:#define syslogd_full_usage "\n\n"
+//usage:       "System logging utility\n"
+//usage:	IF_NOT_FEATURE_SYSLOGD_CFG(
+//usage:       "(this version of syslogd ignores /etc/syslog.conf)\n"
+//usage:	)
+//usage:     "\n	-n		Run in foreground"
+//usage:     "\n	-O FILE		Log to FILE (default:/var/log/messages)"
+//usage:     "\n	-l N		Log only messages more urgent than prio N (1-8)"
+//usage:     "\n	-S		Smaller output"
+//usage:	IF_FEATURE_ROTATE_LOGFILE(
+//usage:     "\n	-s SIZE		Max size (KB) before rotation (default:200KB, 0=off)"
+//usage:     "\n	-b N		N rotated logs to keep (default:1, max=99, 0=purge)"
+//usage:	)
+//usage:	IF_FEATURE_REMOTE_LOG(
+//usage:     "\n	-R HOST[:PORT]	Log to IP or hostname on PORT (default PORT=514/UDP)"
+//usage:     "\n	-L		Log locally and via network (default is network only if -R)"
+//usage:	)
+//usage:	IF_FEATURE_SYSLOGD_DUP(
+//usage:     "\n	-D		Drop duplicates"
+//usage:	)
+//usage:	IF_FEATURE_IPC_SYSLOG(
+/* NB: -Csize shouldn't have space (because size is optional) */
+//usage:     "\n	-C[size_kb]	Log to shared mem buffer (use logread to read it)"
+//usage:	)
+//usage:	IF_FEATURE_SYSLOGD_CFG(
+//usage:     "\n	-f FILE		Use FILE as config (default:/etc/syslog.conf)"
+//usage:	)
+/* //usage:  "\n	-m MIN		Minutes between MARK lines (default:20, 0=off)" */
+//usage:	IF_FEATURE_KMSG_SYSLOG(
+//usage:     "\n	-K		Log to kernel printk buffer (use dmesg to read it)"
+//usage:	)
+//usage:
+//usage:#define syslogd_example_usage
+//usage:       "$ syslogd -R masterlog:514\n"
+//usage:       "$ syslogd -R 192.168.1.1:601\n"
+
+/*
+ * Done in syslogd_and_logger.c:
+#include "libbb.h"
+#define SYSLOG_NAMES
+#define SYSLOG_NAMES_CONST
+#include <syslog.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
+
+/* Write locking does not seem to be useful either */
+#undef SYSLOGD_WRLOCK
+
+enum {
+	MAX_READ = CONFIG_FEATURE_SYSLOGD_READ_BUFFER_SIZE,
+	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 */
+};
+
+#if ENABLE_FEATURE_REMOTE_LOG
+typedef struct {
+	int remoteFD;
+	unsigned last_dns_resolve;
+	len_and_sockaddr *remoteAddr;
+	const char *remoteHostname;
+} remoteHost_t;
+#endif
+
+typedef struct logFile_t {
+	const char *path;
+	int fd;
+#if ENABLE_FEATURE_ROTATE_LOGFILE
+	unsigned size;
+	uint8_t isRegular;
+#endif
+} logFile_t;
+
+#if ENABLE_FEATURE_SYSLOGD_CFG
+typedef struct logRule_t {
+	uint8_t enabled_facility_priomap[LOG_NFACILITIES];
+	struct logFile_t *file;
+	struct logRule_t *next;
+} logRule_t;
+#endif
+
+/* Allows us to have smaller initializer. Ugly. */
+#define GLOBALS \
+	logFile_t logFile;                      \
+	/* interval between marks in seconds */ \
+	/*int markInterval;*/                   \
+	/* level of messages to be logged */    \
+	int logLevel;                           \
+IF_FEATURE_ROTATE_LOGFILE( \
+	/* max size of file before rotation */  \
+	unsigned logFileSize;                   \
+	/* number of rotated message files */   \
+	unsigned logFileRotate;                 \
+) \
+IF_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];                 \
+) \
+IF_FEATURE_SYSLOGD_CFG( \
+	logRule_t *log_rules; \
+) \
+IF_FEATURE_KMSG_SYSLOG( \
+	int kmsgfd; \
+	int primask; \
+)
+
+struct init_globals {
+	GLOBALS
+};
+
+struct globals {
+	GLOBALS
+
+#if ENABLE_FEATURE_REMOTE_LOG
+	llist_t *remoteHosts;
+#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 = {
+	.logFile = {
+		.path = "/var/log/messages",
+		.fd = -1,
+	},
+#ifdef SYSLOGD_MARK
+	.markInterval = 20 * 60,
+#endif
+	.logLevel = 8,
+#if ENABLE_FEATURE_ROTATE_LOGFILE
+	.logFileSize = 200 * 1024,
+	.logFileRotate = 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
+	IF_FEATURE_ROTATE_LOGFILE(OPTBIT_filesize   ,)	// -s
+	IF_FEATURE_ROTATE_LOGFILE(OPTBIT_rotatecnt  ,)	// -b
+	IF_FEATURE_REMOTE_LOG(    OPTBIT_remotelog  ,)	// -R
+	IF_FEATURE_REMOTE_LOG(    OPTBIT_locallog   ,)	// -L
+	IF_FEATURE_IPC_SYSLOG(    OPTBIT_circularlog,)	// -C
+	IF_FEATURE_SYSLOGD_DUP(   OPTBIT_dup        ,)	// -D
+	IF_FEATURE_SYSLOGD_CFG(   OPTBIT_cfg        ,)	// -f
+	IF_FEATURE_KMSG_SYSLOG(   OPTBIT_kmsg       ,)	// -K
+
+	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    = IF_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_filesize   )) + 0,
+	OPT_rotatecnt   = IF_FEATURE_ROTATE_LOGFILE((1 << OPTBIT_rotatecnt  )) + 0,
+	OPT_remotelog   = IF_FEATURE_REMOTE_LOG(    (1 << OPTBIT_remotelog  )) + 0,
+	OPT_locallog    = IF_FEATURE_REMOTE_LOG(    (1 << OPTBIT_locallog   )) + 0,
+	OPT_circularlog = IF_FEATURE_IPC_SYSLOG(    (1 << OPTBIT_circularlog)) + 0,
+	OPT_dup         = IF_FEATURE_SYSLOGD_DUP(   (1 << OPTBIT_dup        )) + 0,
+	OPT_cfg         = IF_FEATURE_SYSLOGD_CFG(   (1 << OPTBIT_cfg        )) + 0,
+	OPT_kmsg        = IF_FEATURE_KMSG_SYSLOG(   (1 << OPTBIT_kmsg       )) + 0,
+
+};
+#define OPTION_STR "m:nO:l:S" \
+	IF_FEATURE_ROTATE_LOGFILE("s:" ) \
+	IF_FEATURE_ROTATE_LOGFILE("b:" ) \
+	IF_FEATURE_REMOTE_LOG(    "R:" ) \
+	IF_FEATURE_REMOTE_LOG(    "L"  ) \
+	IF_FEATURE_IPC_SYSLOG(    "C::") \
+	IF_FEATURE_SYSLOGD_DUP(   "D"  ) \
+	IF_FEATURE_SYSLOGD_CFG(   "f:" ) \
+	IF_FEATURE_KMSG_SYSLOG(   "K"  )
+#define OPTION_DECL *opt_m, *opt_l \
+	IF_FEATURE_ROTATE_LOGFILE(,*opt_s) \
+	IF_FEATURE_ROTATE_LOGFILE(,*opt_b) \
+	IF_FEATURE_IPC_SYSLOG(    ,*opt_C = NULL) \
+	IF_FEATURE_SYSLOGD_CFG(   ,*opt_f = NULL)
+#define OPTION_PARAM &opt_m, &(G.logFile.path), &opt_l \
+	IF_FEATURE_ROTATE_LOGFILE(,&opt_s) \
+	IF_FEATURE_ROTATE_LOGFILE(,&opt_b) \
+	IF_FEATURE_REMOTE_LOG(    ,&remoteAddrList) \
+	IF_FEATURE_IPC_SYSLOG(    ,&opt_C) \
+	IF_FEATURE_SYSLOGD_CFG(   ,&opt_f)
+
+
+#if ENABLE_FEATURE_SYSLOGD_CFG
+static const CODE* find_by_name(char *name, const CODE* c_set)
+{
+	for (; c_set->c_name; c_set++) {
+		if (strcmp(name, c_set->c_name) == 0)
+			return c_set;
+	}
+	return NULL;
+}
+#endif
+static const CODE* find_by_val(int val, const CODE* c_set)
+{
+	for (; c_set->c_name; c_set++) {
+		if (c_set->c_val == val)
+			return c_set;
+	}
+	return NULL;
+}
+
+#if ENABLE_FEATURE_SYSLOGD_CFG
+static void parse_syslogdcfg(const char *file)
+{
+	char *t;
+	logRule_t **pp_rule;
+	/* tok[0] set of selectors */
+	/* tok[1] file name */
+	/* tok[2] has to be NULL */
+	char *tok[3];
+	parser_t *parser;
+
+	parser = config_open2(file ? file : "/etc/syslog.conf",
+				file ? xfopen_for_read : fopen_for_read);
+	if (!parser)
+		/* didn't find default /etc/syslog.conf */
+		/* proceed as if we built busybox without config support */
+		return;
+
+	/* use ptr to ptr to avoid checking whether head was initialized */
+	pp_rule = &G.log_rules;
+	/* iterate through lines of config, skipping comments */
+	while (config_read(parser, tok, 3, 2, "# \t", PARSE_NORMAL | PARSE_MIN_DIE)) {
+		char *cur_selector;
+		logRule_t *cur_rule;
+
+		/* unexpected trailing token? */
+		if (tok[2])
+			goto cfgerr;
+
+		cur_rule = *pp_rule = xzalloc(sizeof(*cur_rule));
+
+		cur_selector = tok[0];
+		/* iterate through selectors: "kern.info;kern.!err;..." */
+		do {
+			const CODE *code;
+			char *next_selector;
+			uint8_t negated_prio; /* "kern.!err" */
+			uint8_t single_prio;  /* "kern.=err" */
+			uint32_t facmap; /* bitmap of enabled facilities */
+			uint8_t primap;  /* bitmap of enabled priorities */
+			unsigned i;
+
+			next_selector = strchr(cur_selector, ';');
+			if (next_selector)
+				*next_selector++ = '\0';
+
+			t = strchr(cur_selector, '.');
+			if (!t)
+				goto cfgerr;
+			*t++ = '\0'; /* separate facility from priority */
+
+			negated_prio = 0;
+			single_prio = 0;
+			if (*t == '!') {
+				negated_prio = 1;
+				++t;
+			}
+			if (*t == '=') {
+				single_prio = 1;
+				++t;
+			}
+
+			/* parse priority */
+			if (*t == '*')
+				primap = 0xff; /* all 8 log levels enabled */
+			else {
+				uint8_t priority;
+				code = find_by_name(t, prioritynames);
+				if (!code)
+					goto cfgerr;
+				primap = 0;
+				priority = code->c_val;
+				if (priority == INTERNAL_NOPRI) {
+					/* ensure we take "enabled_facility_priomap[fac] &= 0" branch below */
+					negated_prio = 1;
+				} else {
+					priority = 1 << priority;
+					do {
+						primap |= priority;
+						if (single_prio)
+							break;
+						priority >>= 1;
+					} while (priority);
+					if (negated_prio)
+						primap = ~primap;
+				}
+			}
+
+			/* parse facility */
+			if (*cur_selector == '*')
+				facmap = (1<<LOG_NFACILITIES) - 1;
+			else {
+				char *next_facility;
+				facmap = 0;
+				t = cur_selector;
+				/* iterate through facilities: "kern,daemon.<priospec>" */
+				do {
+					next_facility = strchr(t, ',');
+					if (next_facility)
+						*next_facility++ = '\0';
+					code = find_by_name(t, facilitynames);
+					if (!code)
+						goto cfgerr;
+					/* "mark" is not a real facility, skip it */
+					if (code->c_val != INTERNAL_MARK)
+						facmap |= 1<<(LOG_FAC(code->c_val));
+					t = next_facility;
+				} while (t);
+			}
+
+			/* merge result with previous selectors */
+			for (i = 0; i < LOG_NFACILITIES; ++i) {
+				if (!(facmap & (1<<i)))
+					continue;
+				if (negated_prio)
+					cur_rule->enabled_facility_priomap[i] &= primap;
+				else
+					cur_rule->enabled_facility_priomap[i] |= primap;
+			}
+
+			cur_selector = next_selector;
+		} while (cur_selector);
+
+		/* check whether current file name was mentioned in previous rules or
+		 * as global logfile (G.logFile).
+		 */
+		if (strcmp(G.logFile.path, tok[1]) == 0) {
+			cur_rule->file = &G.logFile;
+			goto found;
+		}
+		/* temporarily use cur_rule as iterator, but *pp_rule still points
+		 * to currently processing rule entry.
+		 * NOTE: *pp_rule points to the current (and last in the list) rule.
+		 */
+		for (cur_rule = G.log_rules; cur_rule != *pp_rule; cur_rule = cur_rule->next) {
+			if (strcmp(cur_rule->file->path, tok[1]) == 0) {
+				/* found - reuse the same file structure */
+				(*pp_rule)->file = cur_rule->file;
+				cur_rule = *pp_rule;
+				goto found;
+			}
+		}
+		cur_rule->file = xzalloc(sizeof(*cur_rule->file));
+		cur_rule->file->fd = -1;
+		cur_rule->file->path = xstrdup(tok[1]);
+ found:
+		pp_rule = &cur_rule->next;
+	}
+	config_close(parser);
+	return;
+
+ cfgerr:
+	bb_error_msg_and_die("error in '%s' at line %d",
+			file ? file : "/etc/syslog.conf",
+			parser->lineno);
+}
+#endif
+
+/* 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 old_tail, new_tail;
+	int len;
+
+	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 = strlen(msg) + 1; /* 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
+static void ipcsyslog_cleanup(void) {}
+static void ipcsyslog_init(void) {}
+void log_to_shmem(const char *msg);
+#endif /* FEATURE_IPC_SYSLOG */
+
+#if ENABLE_FEATURE_KMSG_SYSLOG
+static void kmsg_init(void)
+{
+	G.kmsgfd = xopen("/dev/kmsg", O_WRONLY);
+
+	/*
+	 * kernel < 3.5 expects single char printk KERN_* priority prefix,
+	 * from 3.5 onwards the full syslog facility/priority format is supported
+	 */
+	if (get_linux_version_code() < KERNEL_VERSION(3,5,0))
+		G.primask = LOG_PRIMASK;
+	else
+		G.primask = -1;
+}
+
+static void kmsg_cleanup(void)
+{
+	if (ENABLE_FEATURE_CLEAN_UP)
+		close(G.kmsgfd);
+}
+
+/* Write message to /dev/kmsg */
+static void log_to_kmsg(int pri, const char *msg)
+{
+	/*
+	 * kernel < 3.5 expects single char printk KERN_* priority prefix,
+	 * from 3.5 onwards the full syslog facility/priority format is supported
+	 */
+	pri &= G.primask;
+
+	write(G.kmsgfd, G.printbuf, sprintf(G.printbuf, "<%d>%s\n", pri, msg));
+}
+#else
+static void kmsg_init(void) {}
+static void kmsg_cleanup(void) {}
+static void log_to_kmsg(int pri UNUSED_PARAM, const char *msg UNUSED_PARAM) {}
+#endif /* FEATURE_KMSG_SYSLOG */
+
+/* Print a message to the log file. */
+static void log_locally(time_t now, char *msg, logFile_t *log_file)
+{
+#ifdef SYSLOGD_WRLOCK
+	struct flock fl;
+#endif
+	int len = strlen(msg);
+
+	if (log_file->fd >= 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(log_file->fd);
+			goto reopen;
+		}
+	} else {
+ reopen:
+		log_file->fd = open(log_file->path, O_WRONLY | O_CREAT
+					| O_NOCTTY | O_APPEND | O_NONBLOCK,
+					0666);
+		if (log_file->fd < 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;
+			log_file->isRegular = (fstat(log_file->fd, &statf) == 0 && S_ISREG(statf.st_mode));
+			/* bug (mostly harmless): can wrap around if file > 4gb */
+			log_file->size = statf.st_size;
+		}
+#endif
+	}
+
+#ifdef SYSLOGD_WRLOCK
+	fl.l_whence = SEEK_SET;
+	fl.l_start = 0;
+	fl.l_len = 1;
+	fl.l_type = F_WRLCK;
+	fcntl(log_file->fd, F_SETLKW, &fl);
+#endif
+
+#if ENABLE_FEATURE_ROTATE_LOGFILE
+	if (G.logFileSize && log_file->isRegular && log_file->size > G.logFileSize) {
+		if (G.logFileRotate) { /* always 0..99 */
+			int i = strlen(log_file->path) + 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", log_file->path, i);
+				if (i == 0) break;
+				sprintf(oldFile, "%s.%d", log_file->path, --i);
+				/* ignore errors - file might be missing */
+				rename(oldFile, newFile);
+			}
+			/* newFile == "f.0" now */
+			rename(log_file->path, newFile);
+			/* Incredibly, if F and F.0 are hardlinks, POSIX
+			 * _demands_ that rename returns 0 but does not
+			 * remove F!!!
+			 * (hardlinked F/F.0 pair was observed after
+			 * power failure during rename()).
+			 * Ensure old file is gone:
+			 */
+			unlink(log_file->path);
+#ifdef SYSLOGD_WRLOCK
+			fl.l_type = F_UNLCK;
+			fcntl(log_file->fd, F_SETLKW, &fl);
+#endif
+			close(log_file->fd);
+			goto reopen;
+		}
+		ftruncate(log_file->fd, 0);
+	}
+	log_file->size +=
+#endif
+			full_write(log_file->fd, msg, len);
+#ifdef SYSLOGD_WRLOCK
+	fl.l_type = F_UNLCK;
+	fcntl(log_file->fd, F_SETLKW, &fl);
+#endif
+}
+
+static void parse_fac_prio_20(int pri, char *res20)
+{
+	const CODE *c_pri, *c_fac;
+
+	c_fac = find_by_val(LOG_FAC(pri) << 3, facilitynames);
+	if (c_fac) {
+		c_pri = find_by_val(LOG_PRI(pri), prioritynames);
+		if (c_pri) {
+			snprintf(res20, 20, "%s.%s", c_fac->c_name, c_pri->c_name);
+			return;
+		}
+	}
+	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;
+
+	/* Jan 18 00:11:22 msg... */
+	/* 01234567890123456 */
+	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_kmsg) {
+		log_to_kmsg(pri, msg);
+		return;
+	}
+
+	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) */
+#if ENABLE_FEATURE_SYSLOGD_CFG
+	{
+		bool match = 0;
+		logRule_t *rule;
+		uint8_t facility = LOG_FAC(pri);
+		uint8_t prio_bit = 1 << LOG_PRI(pri);
+
+		for (rule = G.log_rules; rule; rule = rule->next) {
+			if (rule->enabled_facility_priomap[facility] & prio_bit) {
+				log_locally(now, G.printbuf, rule->file);
+				match = 1;
+			}
+		}
+		if (match)
+			return;
+	}
+#endif
+	if (LOG_PRI(pri) < G.logLevel) {
+#if ENABLE_FEATURE_IPC_SYSLOG
+		if ((option_mask32 & OPT_circularlog) && G.shbuf) {
+			log_to_shmem(G.printbuf);
+			return;
+		}
+#endif
+		log_locally(now, G.printbuf, &G.logFile);
+	}
+}
+
+static void timestamp_and_log_internal(const char *msg)
+{
+	/* -L, or no -R */
+	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 */
+		timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
+	}
+}
+
+#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;
+
+#if ENABLE_FEATURE_SYSTEMD
+	if (sd_listen_fds() == 1)
+		return SD_LISTEN_FDS_START;
+#endif
+
+	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(remoteHost_t *rh)
+{
+	if (!rh->remoteAddr) {
+		unsigned now = monotonic_sec();
+
+		/* Don't resolve name too often - DNS timeouts can be big */
+		if ((now - rh->last_dns_resolve) < DNS_WAIT_SEC)
+			return -1;
+		rh->last_dns_resolve = now;
+		rh->remoteAddr = host2sockaddr(rh->remoteHostname, 514);
+		if (!rh->remoteAddr)
+			return -1;
+	}
+	return xsocket(rh->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_REMOTE_LOG
+	llist_t *item;
+#endif
+#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 (so that they interrupt read()) */
+	signal_no_SA_RESTART_empty_mask(SIGTERM, record_signo);
+	signal_no_SA_RESTART_empty_mask(SIGINT, record_signo);
+	//signal_no_SA_RESTART_empty_mask(SIGQUIT, record_signo);
+	signal(SIGHUP, SIG_IGN);
+#ifdef SYSLOGD_MARK
+	signal(SIGALRM, do_mark);
+	alarm(G.markInterval);
+#endif
+	sock_fd = create_socket();
+
+	if (option_mask32 & OPT_circularlog)
+		ipcsyslog_init();
+
+	if (option_mask32 & OPT_kmsg)
+		kmsg_init();
+
+	timestamp_and_log_internal("syslogd started: BusyBox v" BB_VER);
+
+	while (!bb_got_signal) {
+		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 = read(sock_fd, recvbuf, MAX_READ - 1);
+		if (sz < 0) {
+			if (!bb_got_signal)
+				bb_perror_msg("read from /dev/log");
+			break;
+		}
+
+		/* 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
+		/* Stock syslogd sends it '\n'-terminated
+		 * over network, mimic that */
+		recvbuf[sz] = '\n';
+
+		/* We are not modifying log messages in any way before send */
+		/* Remote site cannot trust _us_ anyway and need to do validation again */
+		for (item = G.remoteHosts; item != NULL; item = item->link) {
+			remoteHost_t *rh = (remoteHost_t *)item->data;
+
+			if (rh->remoteFD == -1) {
+				rh->remoteFD = try_to_resolve_remote(rh);
+				if (rh->remoteFD == -1)
+					continue;
+			}
+
+			/* Send message to remote logger.
+			 * On some errors, close and set remoteFD to -1
+			 * so that DNS resolution is retried.
+			 */
+			if (sendto(rh->remoteFD, recvbuf, sz+1,
+					MSG_DONTWAIT | MSG_NOSIGNAL,
+					&(rh->remoteAddr->u.sa), rh->remoteAddr->len) == -1
+			) {
+				switch (errno) {
+				case ECONNRESET:
+				case ENOTCONN: /* paranoia */
+				case EPIPE:
+					close(rh->remoteFD);
+					rh->remoteFD = -1;
+					free(rh->remoteAddr);
+					rh->remoteAddr = NULL;
+				}
+			}
+		}
+#endif
+		if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) {
+			recvbuf[sz] = '\0'; /* ensure it *is* NUL terminated */
+			split_escape_and_log(recvbuf, sz);
+		}
+	} /* while (!bb_got_signal) */
+
+	timestamp_and_log_internal("syslogd exiting");
+	puts("syslogd exiting");
+	remove_pidfile(CONFIG_PID_FILE_PATH "/syslogd.pid");
+	ipcsyslog_cleanup();
+	if (option_mask32 & OPT_kmsg)
+		kmsg_cleanup();
+	kill_myself_with_sig(bb_got_signal);
+#undef recvbuf
+}
+
+int syslogd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int syslogd_main(int argc UNUSED_PARAM, char **argv)
+{
+	int opts;
+	char OPTION_DECL;
+#if ENABLE_FEATURE_REMOTE_LOG
+	llist_t *remoteAddrList = NULL;
+#endif
+
+	INIT_G();
+
+	/* No non-option params, -R can occur multiple times */
+	opt_complementary = "=0" IF_FEATURE_REMOTE_LOG(":R::");
+	opts = getopt32(argv, OPTION_STR, OPTION_PARAM);
+#if ENABLE_FEATURE_REMOTE_LOG
+	while (remoteAddrList) {
+		remoteHost_t *rh = xzalloc(sizeof(*rh));
+		rh->remoteHostname = llist_pop(&remoteAddrList);
+		rh->remoteFD = -1;
+		rh->last_dns_resolve = monotonic_sec() - DNS_WAIT_SEC - 1;
+		llist_add_to(&G.remoteHosts, rh);
+	}
+#endif
+
+#ifdef SYSLOGD_MARK
+	if (opts & OPT_mark) // -m
+		G.markInterval = xatou_range(opt_m, 0, INT_MAX/60) * 60;
+#endif
+	//if (opts & OPT_nofork) // -n
+	//if (opts & OPT_outfile) // -O
+	if (opts & OPT_loglevel) // -l
+		G.logLevel = xatou_range(opt_l, 1, 8);
+	//if (opts & OPT_small) // -S
+#if ENABLE_FEATURE_ROTATE_LOGFILE
+	if (opts & OPT_filesize) // -s
+		G.logFileSize = xatou_range(opt_s, 0, INT_MAX/1024) * 1024;
+	if (opts & 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 && !(opts & OPT_remotelog)) // -R
+		option_mask32 |= OPT_locallog;
+#if ENABLE_FEATURE_SYSLOGD_CFG
+	parse_syslogdcfg(opt_f);
+#endif
+
+	/* Store away localhost's name before the fork */
+	G.hostname = safe_gethostname();
+	*strchrnul(G.hostname, '.') = '\0';
+
+	if (!(opts & OPT_nofork)) {
+		bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
+	}
+
+	//umask(0); - why??
+	write_pidfile(CONFIG_PID_FILE_PATH "/syslogd.pid");
+
+	do_syslogd();
+	/* return EXIT_SUCCESS; */
+}
+
+/* Clean up. Needed because we are included from syslogd_and_logger.c */
+#undef DEBUG
+#undef SYSLOGD_MARK
+#undef SYSLOGD_WRLOCK
+#undef G
+#undef GLOBALS
+#undef INIT_G
+#undef OPTION_STR
+#undef OPTION_DECL
+#undef OPTION_PARAM