syslogd: reduce data/bss usage. Code size is practically the same.

This commit is contained in:
Denis Vlasenko 2007-03-15 19:50:46 +00:00
parent bff32ce4d5
commit 5e892bae51

View File

@ -17,47 +17,107 @@
#include <paths.h>
#include <sys/un.h>
/* SYSLOG_NAMES defined to pull some extra junk from syslog.h */
/* SYSLOG_NAMES defined to pull some extra junk from syslog.h: */
/* prioritynames[] and facilitynames[]. uclibc pulls those in _rwdata_! :( */
#define SYSLOG_NAMES
#include <sys/syslog.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
/* Path for the file where all log messages are written */
static const char *logFilePath = "/var/log/messages";
static int logFD = -1;
// Semaphore operation structures
struct shbuf_ds {
int32_t size; // size of data written
int32_t head; // start of message list
int32_t tail; // end of message list
char data[1]; // data/messages
}; // shared memory pointer
struct globals {
const char *logFilePath;
int logFD;
/* This 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) */
#ifdef SYSLOGD_MARK
/* interval between marks in seconds */
static int markInterval = 20 * 60;
int markInterval;
#endif
/* level of messages to be locally logged */
static int logLevel = 8;
/* localhost's name */
static char localHostName[64];
int logLevel;
#if ENABLE_FEATURE_ROTATE_LOGFILE
/* max size of message file before being rotated */
static unsigned logFileSize = 200 * 1024;
unsigned logFileSize;
/* number of rotated message files */
static unsigned logFileRotate = 1;
static unsigned curFileSize;
static smallint isRegular;
unsigned logFileRotate;
unsigned curFileSize;
smallint isRegular;
#endif
#if ENABLE_FEATURE_REMOTE_LOG
#include <netinet/in.h>
/* udp socket for logging to remote host */
static int remoteFD = -1;
static len_and_sockaddr* remoteAddr;
int remoteFD;
len_and_sockaddr* remoteAddr;
#endif
#if ENABLE_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 shbuf_ds *shbuf;
#endif
time_t last_log_time;
/* localhost's name */
char localHostName[64];
}; /* struct globals */
static const struct globals init_globals = {
.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
// FIXME: hidden tail with lotsa zeroes is here....
};
#define G (*ptr_to_globals)
/* We are using bb_common_bufsiz1 for buffering: */
enum { MAX_READ = (BUFSIZ/6) & ~0xf };
/* We recv into RECVBUF... (size: MAX_READ ~== BUFSIZ/6) */
@ -109,7 +169,7 @@ enum {
USE_FEATURE_ROTATE_LOGFILE(,*opt_b) \
USE_FEATURE_REMOTE_LOG( ,*opt_R) \
USE_FEATURE_IPC_SYSLOG( ,*opt_C = NULL)
#define OPTION_PARAM &opt_m, &logFilePath, &opt_l \
#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( ,&opt_R) \
@ -119,68 +179,51 @@ enum {
/* 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
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/shm.h>
/* our shared key */
#define KEY_ID ((long)0x414e4547) /* "GENA" */
// Semaphore operation structures
static struct shbuf_ds {
int32_t size; // size of data written
int32_t head; // start of message list
int32_t tail; // end of message list
char data[1]; // data/messages
} *shbuf; // shared memory pointer
static int shmid = -1; // ipc shared memory id
static int s_semid = -1; // ipc semaphore id
static int shm_size = ((CONFIG_FEATURE_IPC_SYSLOG_BUFFER_SIZE)*1024); // default shm size
static void ipcsyslog_cleanup(void)
{
if (shmid != -1) {
shmdt(shbuf);
if (G.shmid != -1) {
shmdt(G.shbuf);
}
if (shmid != -1) {
shmctl(shmid, IPC_RMID, NULL);
if (G.shmid != -1) {
shmctl(G.shmid, IPC_RMID, NULL);
}
if (s_semid != -1) {
semctl(s_semid, 0, IPC_RMID, 0);
if (G.s_semid != -1) {
semctl(G.s_semid, 0, IPC_RMID, 0);
}
}
static void ipcsyslog_init(void)
{
if (DEBUG)
printf("shmget(%lx, %d,...)\n", KEY_ID, shm_size);
printf("shmget(%lx, %d,...)\n", KEY_ID, G.shm_size);
shmid = shmget(KEY_ID, shm_size, IPC_CREAT | 1023);
if (shmid == -1) {
G.shmid = shmget(KEY_ID, G.shm_size, IPC_CREAT | 1023);
if (G.shmid == -1) {
bb_perror_msg_and_die("shmget");
}
shbuf = shmat(shmid, NULL, 0);
if (!shbuf) {
G.shbuf = shmat(G.shmid, NULL, 0);
if (!G.shbuf) {
bb_perror_msg_and_die("shmat");
}
shbuf->size = shm_size - offsetof(struct shbuf_ds, data);
shbuf->head = shbuf->tail = 0;
G.shbuf->size = G.shm_size - offsetof(struct shbuf_ds, data);
G.shbuf->head = G.shbuf->tail = 0;
// we'll trust the OS to set initial semval to 0 (let's hope)
s_semid = semget(KEY_ID, 2, IPC_CREAT | IPC_EXCL | 1023);
if (s_semid == -1) {
G.s_semid = semget(KEY_ID, 2, IPC_CREAT | IPC_EXCL | 1023);
if (G.s_semid == -1) {
if (errno == EEXIST) {
s_semid = semget(KEY_ID, 2, 0);
if (s_semid != -1)
G.s_semid = semget(KEY_ID, 2, 0);
if (G.s_semid != -1)
return;
}
bb_perror_msg_and_die("semget");
@ -190,14 +233,10 @@ static void ipcsyslog_init(void)
/* Write message to shared mem buffer */
static void log_to_shmem(const char *msg, int len)
{
/* Why libc insists on these being rw? */
static struct sembuf SMwup[1] = { {1, -1, IPC_NOWAIT} };
static struct sembuf SMwdn[3] = { {0, 0}, {1, 0}, {1, +1} };
int old_tail, new_tail;
char *c;
if (semop(s_semid, SMwdn, 3) == -1) {
if (semop(G.s_semid, G.SMwdn, 3) == -1) {
bb_perror_msg_and_die("SMwdn");
}
@ -212,53 +251,53 @@ static void log_to_shmem(const char *msg, int len)
*/
len++; /* length with NUL included */
again:
old_tail = shbuf->tail;
old_tail = G.shbuf->tail;
new_tail = old_tail + len;
if (new_tail < shbuf->size) {
if (new_tail < G.shbuf->size) {
/* No need to move head if shbuf->head <= old_tail,
* else... */
if (old_tail < shbuf->head && shbuf->head <= new_tail) {
if (old_tail < G.shbuf->head && G.shbuf->head <= new_tail) {
/* ...need to move head forward */
c = memchr(shbuf->data + new_tail, '\0',
shbuf->size - new_tail);
c = memchr(G.shbuf->data + new_tail, '\0',
G.shbuf->size - new_tail);
if (!c) /* no NUL ahead of us, wrap around */
c = memchr(shbuf->data, '\0', old_tail);
c = memchr(G.shbuf->data, '\0', old_tail);
if (!c) { /* still nothing? point to this msg... */
shbuf->head = old_tail;
G.shbuf->head = old_tail;
} else {
/* convert pointer to offset + skip NUL */
shbuf->head = c - shbuf->data + 1;
G.shbuf->head = c - G.shbuf->data + 1;
}
}
/* store message, set new tail */
memcpy(shbuf->data + old_tail, msg, len);
shbuf->tail = new_tail;
memcpy(G.shbuf->data + old_tail, msg, len);
G.shbuf->tail = new_tail;
} else {
/* we need to break up the message and wrap it around */
/* k == available buffer space ahead of old tail */
int k = shbuf->size - old_tail - 1;
if (shbuf->head > old_tail) {
int k = G.shbuf->size - old_tail - 1;
if (G.shbuf->head > old_tail) {
/* we are going to overwrite head, need to
* move it out of the way */
c = memchr(shbuf->data, '\0', old_tail);
c = memchr(G.shbuf->data, '\0', old_tail);
if (!c) { /* nothing? point to this msg... */
shbuf->head = old_tail;
G.shbuf->head = old_tail;
} else { /* convert pointer to offset + skip NUL */
shbuf->head = c - shbuf->data + 1;
G.shbuf->head = c - G.shbuf->data + 1;
}
}
/* copy what fits to the end of buffer, and repeat */
memcpy(shbuf->data + old_tail, msg, k);
memcpy(G.shbuf->data + old_tail, msg, k);
msg += k;
len -= k;
shbuf->tail = 0;
G.shbuf->tail = 0;
goto again;
}
if (semop(s_semid, SMwup, 1) == -1) {
if (semop(G.s_semid, G.SMwup, 1) == -1) {
bb_perror_msg_and_die("SMwup");
}
if (DEBUG)
printf("head:%d tail:%d\n", shbuf->head, shbuf->tail);
printf("head:%d tail:%d\n", G.shbuf->head, G.shbuf->tail);
}
#else
void ipcsyslog_cleanup(void);
@ -270,29 +309,28 @@ void log_to_shmem(const char *msg);
/* Print a message to the log file. */
static void log_locally(char *msg)
{
static time_t last;
struct flock fl;
int len = strlen(msg);
#if ENABLE_FEATURE_IPC_SYSLOG
if ((option_mask32 & OPT_circularlog) && shbuf) {
if ((option_mask32 & OPT_circularlog) && G.shbuf) {
log_to_shmem(msg, len);
return;
}
#endif
if (logFD >= 0) {
if (G.logFD >= 0) {
time_t cur;
time(&cur);
if (last != cur) {
last = cur; /* reopen log file every second */
close(logFD);
if (G.last_log_time != cur) {
G.last_log_time = cur; /* reopen log file every second */
close(G.logFD);
goto reopen;
}
} else {
reopen:
logFD = device_open(logFilePath, O_WRONLY | O_CREAT
G.logFD = device_open(G.logFilePath, O_WRONLY | O_CREAT
| O_NOCTTY | O_APPEND | O_NONBLOCK);
if (logFD < 0) {
if (G.logFD < 0) {
/* cannot open logfile? - print to /dev/console then */
int fd = device_open(_PATH_CONSOLE, O_WRONLY | O_NOCTTY | O_NONBLOCK);
if (fd < 0)
@ -306,9 +344,9 @@ static void log_locally(char *msg)
{
struct stat statf;
isRegular = (fstat(logFD, &statf) == 0 && (statf.st_mode & S_IFREG));
G.isRegular = (fstat(G.logFD, &statf) == 0 && (statf.st_mode & S_IFREG));
/* bug (mostly harmless): can wrap around if file > 4gb */
curFileSize = statf.st_size;
G.curFileSize = statf.st_size;
}
#endif
}
@ -317,36 +355,36 @@ static void log_locally(char *msg)
fl.l_start = 0;
fl.l_len = 1;
fl.l_type = F_WRLCK;
fcntl(logFD, F_SETLKW, &fl);
fcntl(G.logFD, F_SETLKW, &fl);
#if ENABLE_FEATURE_ROTATE_LOGFILE
if (logFileSize && isRegular && curFileSize > logFileSize) {
if (logFileRotate) { /* always 0..99 */
int i = strlen(logFilePath) + 3 + 1;
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 = logFileRotate - 1;
i = G.logFileRotate - 1;
/* rename: f.8 -> f.9; f.7 -> f.8; ... */
while (1) {
sprintf(newFile, "%s.%d", logFilePath, i);
sprintf(newFile, "%s.%d", G.logFilePath, i);
if (i == 0) break;
sprintf(oldFile, "%s.%d", logFilePath, --i);
sprintf(oldFile, "%s.%d", G.logFilePath, --i);
rename(oldFile, newFile);
}
/* newFile == "f.0" now */
rename(logFilePath, newFile);
rename(G.logFilePath, newFile);
fl.l_type = F_UNLCK;
fcntl(logFD, F_SETLKW, &fl);
close(logFD);
fcntl(G.logFD, F_SETLKW, &fl);
close(G.logFD);
goto reopen;
}
ftruncate(logFD, 0);
ftruncate(G.logFD, 0);
}
curFileSize +=
G.curFileSize +=
#endif
full_write(logFD, msg, len);
full_write(G.logFD, msg, len);
fl.l_type = F_UNLCK;
fcntl(logFD, F_SETLKW, &fl);
fcntl(G.logFD, F_SETLKW, &fl);
}
static void parse_fac_prio_20(int pri, char *res20)
@ -397,13 +435,13 @@ static void timestamp_and_log(int pri, char *msg, int len)
/* Log message locally (to file or shared mem) */
if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) {
if (LOG_PRI(pri) < logLevel) {
if (LOG_PRI(pri) < G.logLevel) {
if (option_mask32 & OPT_small)
sprintf(PRINTBUF, "%s %s\n", timestamp, msg);
else {
char res[20];
parse_fac_prio_20(pri, res);
sprintf(PRINTBUF, "%s %s %s %s\n", timestamp, localHostName, res, msg);
sprintf(PRINTBUF, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
}
log_locally(PRINTBUF);
}
@ -456,9 +494,9 @@ static void quit_signal(int sig)
#ifdef SYSLOGD_MARK
static void do_mark(int sig)
{
if (markInterval) {
if (G.markInterval) {
timestamp_and_log(LOG_SYSLOG | LOG_INFO, (char*)"-- MARK --", 0);
alarm(markInterval);
alarm(G.markInterval);
}
}
#endif
@ -482,7 +520,7 @@ static void do_syslogd(void)
#endif
#ifdef SYSLOGD_MARK
signal(SIGALRM, do_mark);
alarm(markInterval);
alarm(G.markInterval);
#endif
memset(&sunx, 0, sizeof(sunx));
@ -541,14 +579,14 @@ static void do_syslogd(void)
#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 (remoteAddr) {
if (-1 == remoteFD) {
remoteFD = socket(remoteAddr->sa.sa_family, SOCK_DGRAM, 0);
if (G.remoteAddr) {
if (-1 == G.remoteFD) {
G.remoteFD = socket(G.remoteAddr->sa.sa_family, SOCK_DGRAM, 0);
}
if (-1 != remoteFD) {
if (-1 != G.remoteFD) {
/* send message to remote logger, ignore possible error */
sendto(remoteFD, RECVBUF, i, MSG_DONTWAIT,
&remoteAddr->sa, remoteAddr->len);
sendto(G.remoteFD, RECVBUF, i, MSG_DONTWAIT,
&G.remoteAddr->sa, G.remoteAddr->len);
}
}
#endif
@ -564,33 +602,36 @@ int syslogd_main(int argc, char **argv)
char OPTION_DECL;
char *p;
PTR_TO_GLOBALS = xzalloc(sizeof(G));
memcpy(ptr_to_globals, &init_globals, sizeof(init_globals));
/* do normal option parsing */
opt_complementary = "=0"; /* no non-option params */
getopt32(argc, argv, OPTION_STR, OPTION_PARAM);
#ifdef SYSLOGD_MARK
if (option_mask32 & OPT_mark) // -m
markInterval = xatou_range(opt_m, 0, INT_MAX/60) * 60;
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
logLevel = xatou_range(opt_l, 1, 8);
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
logFileSize = xatou_range(opt_s, 0, INT_MAX/1024) * 1024;
G.logFileSize = xatou_range(opt_s, 0, INT_MAX/1024) * 1024;
if (option_mask32 & OPT_rotatecnt) // -b
logFileRotate = xatou_range(opt_b, 0, 99);
G.logFileRotate = xatou_range(opt_b, 0, 99);
#endif
#if ENABLE_FEATURE_REMOTE_LOG
if (option_mask32 & OPT_remotelog) { // -R
remoteAddr = xhost2sockaddr(opt_R, 514);
G.remoteAddr = xhost2sockaddr(opt_R, 514);
}
//if (option_mask32 & OPT_locallog) // -L
#endif
#if ENABLE_FEATURE_IPC_SYSLOG
if (opt_C) // -Cn
shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;
G.shm_size = xatoul_range(opt_C, 4, INT_MAX/1024) * 1024;
#endif
/* If they have not specified remote logging, then log locally */
@ -598,8 +639,8 @@ int syslogd_main(int argc, char **argv)
option_mask32 |= OPT_locallog;
/* Store away localhost's name before the fork */
gethostname(localHostName, sizeof(localHostName));
p = strchr(localHostName, '.');
gethostname(G.localHostName, sizeof(G.localHostName));
p = strchr(G.localHostName, '.');
if (p) {
*p = '\0';
}