emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

syslogd: start using bb_common_bufsiz1 instead of stack/malloc

Browse Source 
logger: optimize, also use bb_common_bufsiz1 (~40 bytes)
tested to eat arbitrarily-sized input at high speed - ok
This commit is contained in:
Denis Vlasenko
2007-01-04 21:22:11 +00:00
parent b893497151
commit a0e2a0a192
3 changed files with 61 additions and 70 deletions
Download Patch File Download Diff File Expand all files Collapse all files

59
sysklogd/syslogd.c
View File

@ -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 };
/* 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 */
/* Correct regardless of combination of CONFIG_xxx */
/* 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 */
}