From 5e892bae51a1f4414006a70f37d87b339e943cba Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Thu, 15 Mar 2007 19:50:46 +0000 Subject: [PATCH] syslogd: reduce data/bss usage. Code size is practically the same. --- sysklogd/syslogd.c | 299 ++++++++++++++++++++++++++------------------- 1 file changed, 170 insertions(+), 129 deletions(-) diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c index 53cb4ba5e..8ae75c974 100644 --- a/sysklogd/syslogd.c +++ b/sysklogd/syslogd.c @@ -17,47 +17,107 @@ #include #include -/* 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 #include -#define DEBUG 0 - -/* Path for the file where all log messages are written */ -static const char *logFilePath = "/var/log/messages"; -static int logFD = -1; - -/* 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; +#if ENABLE_FEATURE_REMOTE_LOG +#include #endif -/* level of messages to be locally logged */ -static int logLevel = 8; +#if ENABLE_FEATURE_IPC_SYSLOG +#include +#include +#include +#endif -/* localhost's name */ -static char localHostName[64]; + +#define DEBUG 0 + +// 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 */ + int markInterval; +#endif + + /* level of messages to be locally logged */ + int logLevel; #if ENABLE_FEATURE_ROTATE_LOGFILE -/* max size of message file before being rotated */ -static unsigned logFileSize = 200 * 1024; -/* number of rotated message files */ -static unsigned logFileRotate = 1; -static unsigned curFileSize; -static smallint isRegular; + /* max size of message file before being rotated */ + unsigned logFileSize; + /* number of rotated message files */ + unsigned logFileRotate; + unsigned curFileSize; + smallint isRegular; #endif #if ENABLE_FEATURE_REMOTE_LOG -#include -/* udp socket for logging to remote host */ -static int remoteFD = -1; -static len_and_sockaddr* remoteAddr; + /* udp socket for logging to remote host */ + 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 -#include -#include - /* 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'; }