diff options
Diffstat (limited to 'sysklogd/syslogd.c')
| -rw-r--r-- | sysklogd/syslogd.c | 63 |
1 files changed, 35 insertions, 28 deletions
diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c index 7edce7a0a..fbb85338a 100644 --- a/sysklogd/syslogd.c +++ b/sysklogd/syslogd.c @@ -56,13 +56,23 @@ static int remoteFD = -1; static struct sockaddr_in remoteAddr; #endif - -/* NB: we may need 2x this amount on stack... */ -enum { MAX_READ = 1024 }; - - -/* options */ -/* Correct regardless of combination of CONFIG_xxx */ +/* We are using bb_common_bufsiz1 for buffering: */ +enum { MAX_READ = (BUFSIZ/6) & ~0xf }; +/* We recv into this... (size: MAX_READ ~== BUFSIZ/6) */ +#define RECVBUF bb_common_bufsiz1 +/* ...then copy here, escaping control chars */ +/* (can grow x2 + 1 max ~== BUFSIZ/3) */ +#define PARSEBUF (bb_common_bufsiz1 + MAX_READ) +/* ...then sprintf into this, adding timestamp (15 chars), + * host (64), fac.prio (20) to the message */ +/* (growth by: 15 + 64 + 20 + delims = ~110) */ +#define PRINTBUF (bb_common_bufsiz1 + 3*MAX_READ + 0x10) +/* totals: BUFSIZ/6 + BUFSIZ/3 + BUFSIZ/3 = BUFSIZ - BUFSIZ/6 + * -- we have BUFSIZ/6 extra at the ent of PRINTBUF + * which covers needed ~110 extra bytes (and much more) */ + + +/* Options */ enum { OPTBIT_mark = 0, // -m OPTBIT_nofork, // -n @@ -175,11 +185,12 @@ static void ipcsyslog_init(void) } } -/* write message to buffer */ +/* Write message to shared mem buffer */ static void log_to_shmem(const char *msg, int len) { - static /*const*/ struct sembuf SMwup[1] = { {1, -1, IPC_NOWAIT} }; - static /*const*/ struct sembuf SMwdn[3] = { {0, 0}, {1, 0}, {1, +1} }; + /* 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; @@ -362,9 +373,9 @@ static void parse_fac_prio_20(int pri, char *res20) } } -/* len parameter is used only for "is there a timestamp?" check +/* len parameter is used only for "is there a timestamp?" check. * NB: some callers cheat and supply 0 when they know - * that there is no timestamp, short-cutting the test */ + * that there is no timestamp, short-cutting the test. */ static void timestamp_and_log(int pri, char *msg, int len) { time_t now; @@ -385,31 +396,29 @@ static void timestamp_and_log(int pri, char *msg, int len) if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) { if (LOG_PRI(pri) < logLevel) { if (option_mask32 & OPT_small) - msg = xasprintf("%s %s\n", timestamp, msg); + sprintf(PRINTBUF, "%s %s\n", timestamp, msg); else { char res[20]; parse_fac_prio_20(pri, res); - msg = xasprintf("%s %s %s %s\n", timestamp, localHostName, res, msg); + sprintf(PRINTBUF, "%s %s %s %s\n", timestamp, localHostName, res, msg); } - log_locally(msg); - free(msg); + log_locally(PRINTBUF); } } } static void split_escape_and_log(char *tmpbuf, int len) { - char line[len * 2 + 1]; /* gcc' cheap alloca */ char *p = tmpbuf; tmpbuf += len; while (p < tmpbuf) { char c; - char *q = line; + char *q = PARSEBUF; int pri = (LOG_USER | LOG_NOTICE); if (*p == '<') { - /* Parse the magic priority number. */ + /* Parse the magic priority number */ pri = bb_strtou(p + 1, &p, 10); if (*p == '>') p++; if (pri & ~(LOG_FACMASK | LOG_PRIMASK)) { @@ -427,8 +436,8 @@ static void split_escape_and_log(char *tmpbuf, int len) *q++ = c; } *q = '\0'; - /* now log it */ - timestamp_and_log(pri, line, q - line); + /* Now log it */ + timestamp_and_log(pri, PARSEBUF, q - PARSEBUF); } } @@ -509,11 +518,10 @@ static void do_syslogd(void) if (FD_ISSET(sock_fd, &fds)) { int i; -#define tmpbuf bb_common_bufsiz1 - i = recv(sock_fd, tmpbuf, MAX_READ, 0); + i = recv(sock_fd, RECVBUF, MAX_READ - 1, 0); if (i <= 0) bb_perror_msg_and_die("UNIX socket error"); - /* TODO: maybe supress duplicates? */ + /* TODO: maybe suppress duplicates? */ #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 */ @@ -523,15 +531,14 @@ static void do_syslogd(void) } if (-1 != remoteFD) { /* send message to remote logger, ignore possible error */ - sendto(remoteFD, tmpbuf, i, MSG_DONTWAIT, + sendto(remoteFD, RECVBUF, i, MSG_DONTWAIT, (struct sockaddr *) &remoteAddr, sizeof(remoteAddr)); } } #endif - tmpbuf[i] = '\0'; - split_escape_and_log(tmpbuf, i); -#undef tmpbuf + RECVBUF[i] = '\0'; + split_escape_and_log(RECVBUF, i); } /* FD_ISSET() */ } /* for */ } |