[BusyBox] Syslogd, klogd, "Circular Buffer" patch.
Gennady Feldman
gena01 at cachier.com
Wed Mar 7 19:32:02 UTC 2001
Here is my current patch which has a rather extensive change list:
- new klogd module
- new logread module (to read "Circular buffer)
- single threaded syslogd (somewhat cleaned up)
P.S. Let me know if I missed something or did something really stupid.
G.F.
-------------- next part --------------
Index: Config.h
===================================================================
RCS file: /var/cvs/busybox/Config.h,v
retrieving revision 1.46
diff -u -r1.46 Config.h
--- Config.h 2001/03/06 00:48:59 1.46
+++ Config.h 2001/03/07 19:10:15
@@ -37,47 +37,48 @@
+#define BB_KLOGD
//#define BB_LENGTH
@@ -200,6 +201,9 @@
// enable syslogd -R remotehost
#define BB_FEATURE_REMOTE_LOG
//
+// enable syslogd -C
+//#define BB_FEATURE_IPC_SYSLOG
+//
//Simple tail implementation (2.34k vs 3k for the full one).
//Both provide 'tail -f', but this cuts out -c, -q, -s, and -v.
#define BB_FEATURE_SIMPLE_TAIL
@@ -412,6 +416,12 @@
#if defined BB_INSMOD || defined BB_LSMOD
#if ! defined BB_FEATURE_NEW_MODULE_INTERFACE && ! defined BB_FEATURE_OLD_MODULE_INTERFACE
#define BB_FEATURE_NEW_MODULE_INTERFACE
+#endif
+#endif
+//
+#ifdef BB_SYSLOGD
+#if defined BB_FEATURE_IPC_SYSLOG
+#define BB_LOGREAD
#endif
#endif
//
Index: applets.h
===================================================================
RCS file: /var/cvs/busybox/applets.h,v
retrieving revision 1.16
diff -u -r1.16 applets.h
--- applets.h 2001/03/02 19:08:50 1.16
+++ applets.h 2001/03/07 19:10:16
@@ -191,6 +191,9 @@
#ifdef BB_KILLALL
APPLET(killall, kill_main, _BB_DIR_USR_BIN)
#endif
+#ifdef BB_KLOGD
+ APPLET(klogd, klogd_main, _BB_DIR_SBIN)
+#endif
#ifdef BB_LENGTH
APPLET(length, length_main, _BB_DIR_USR_BIN)
#endif
@@ -214,6 +217,9 @@
#endif
#ifdef BB_LOGNAME
APPLET(logname, logname_main, _BB_DIR_USR_BIN)
+#endif
+#ifdef BB_LOGREAD
+ APPLET(logread, logread_main, _BB_DIR_SBIN)
#endif
#ifdef BB_LS
APPLET(ls, ls_main, _BB_DIR_BIN)
Index: busybox.h
===================================================================
RCS file: /var/cvs/busybox/busybox.h,v
retrieving revision 1.33
diff -u -r1.33 busybox.h
--- busybox.h 2001/03/01 18:51:33 1.33
+++ busybox.h 2001/03/07 19:10:17
@@ -204,6 +204,11 @@
#define RB_POWER_OFF 0x4321fedc
#endif
+#if defined(BB_KLOGD) || defined(BB_LOGGER)
+void syslog_msg_with_name(const char *name, int facility, int pri, const char *msg);
+void syslog_msg(int facility, int pri, const char *msg);
+#endif
+
/* Include our own copy of struct sysinfo to avoid binary compatability
* problems with Linux 2.4, which changed things. Grumble, grumble. */
struct sysinfo {
Index: logger.c
===================================================================
RCS file: /var/cvs/busybox/logger.c,v
retrieving revision 1.30
diff -u -r1.30 logger.c
--- logger.c 2001/02/20 06:14:07 1.30
+++ logger.c 2001/03/07 19:10:17
@@ -148,9 +148,10 @@
message[strlen(message)-1] = '\0';
}
- openlog(name, option, (pri | LOG_FACMASK));
+ /*openlog(name, option, (pri | LOG_FACMASK));
syslog(pri, "%s", message);
- closelog();
+ closelog();*/
+ syslog_msg_with_name(name,(pri | LOG_FACMASK),pri,message);
return EXIT_SUCCESS;
}
Index: syslogd.c
===================================================================
RCS file: /var/cvs/busybox/syslogd.c,v
retrieving revision 1.58
diff -u -r1.58 syslogd.c
--- syslogd.c 2001/02/20 06:14:08 1.58
+++ syslogd.c 2001/03/07 19:10:18
@@ -7,6 +7,8 @@
*
+ * Copyright (C) 2001 by Gennady Feldman <gfeldman at mail.com>
+ * Changes:
+ * Added "circular buffer" code.
+ * Cleanup to use one thread instead of doing fork().
+ *
* Copyright (C) 2000 by Karl M. Hegbloom <karlheg at debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
@@ -40,25 +42,8 @@
#include <sys/un.h>
#include <sys/param.h>
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
-#include <sys/syscall.h>
-#include <linux/unistd.h>
-typedef unsigned int socklen_t;
-
-#ifndef __alpha__
-# define __NR_klogctl __NR_syslog
-static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
-#else /* __alpha__ */
-#define klogctl syslog
-#endif
-
-#else
-# include <sys/klog.h>
-#endif
#include "busybox.h"
-
-
/* SYSLOG_NAMES defined to pull some extra junk from syslog.h */
#define SYSLOG_NAMES
#include <sys/syslog.h>
@@ -91,6 +76,184 @@
static int local_logging = FALSE;
#endif
+/* circular buffer variables/structures */
+#ifdef BB_FEATURE_IPC_SYSLOG
+
+#include <sys/ipc.h>
+#include <sys/sem.h>
+#include <sys/shm.h>
+
+/* our shared key */
+static const long KEY_ID = 0x414e4547; /*"GENA"*/
+
+// Semaphore operation structures
+static struct shbuf_ds {
+ int size; // size of data written
+ int head; // start of message list
+ int tail; // end of message list
+ char data[1]; // data/messages
+} *buf = NULL; // shared memory pointer
+
+static struct sembuf SMwup[1] = {{1, -1, IPC_NOWAIT}}; // set SMwup
+static struct sembuf SMwdn[3] = {{0, 0}, {1, 0}, {1, +1}}; // set SMwdn
+
+static int shmid = -1; // ipc shared memory id
+static int s_semid = -1; // ipc semaphore id
+int data_size = 16000; // data size
+int shm_size = 16000 + sizeof(*buf); // our buffer size
+static int circular_logging = FALSE;
+
+/*
+ * sem_up - up()'s a semaphore.
+ */
+static inline void sem_up(int semid)
+{
+ if ( semop(semid, SMwup, 1) == -1 )
+ perror_msg_and_die("semop[SMwup]");
+}
+
+/*
+ * sem_down - down()'s a semaphore
+ */
+static inline void sem_down(int semid)
+{
+ if ( semop(semid, SMwdn, 2) == -1 )
+ perror_msg_and_die("semop[SMwdn]");
+}
+
+
+void ipcsyslog_cleanup(void){
+ printf("Exiting Syslogd!\n");
+ if (shmid != -1)
+ shmdt(buf);
+
+ if (shmid != -1)
+ shmctl(shmid, IPC_RMID, NULL);
+ if (s_semid != -1)
+ semctl(s_semid, 0, IPC_RMID, 0);
+}
+
+void ipcsyslog_init(void){
+ if (buf == NULL){
+ if ((shmid = shmget(KEY_ID, shm_size, IPC_CREAT | 1023)) == -1)
+ perror_msg_and_die("shmget");
+
+
+ if ((buf = shmat(shmid, NULL, 0)) == NULL)
+ perror_msg_and_die("shmat");
+
+
+ buf->size=data_size;
+ buf->head=buf->tail=0;
+
+ // we'll trust the OS to set initial semval to 0 (let's hope)
+ if ((s_semid = semget(KEY_ID, 2, IPC_CREAT | IPC_EXCL | 1023)) == -1){
+ if (errno == EEXIST){
+ if ((s_semid = semget(KEY_ID, 2, 0)) == -1)
+ perror_msg_and_die("semget");
+ }else
+ perror_msg_and_die("semget");
+ }
+ }else{
+ printf("Buffer already allocated just grab the semaphore?");
+ }
+}
+
+/* write message to buffer */
+void circ_message(const char *msg){
+ int l=strlen(msg)+1; /* count the whole message w/ '\0' included */
+
+ sem_down(s_semid);
+
+ /*
+ * Circular Buffer Algorithm:
+ * --------------------------
+ *
+ * Start-off w/ empty buffer of specific size SHM_SIZ
+ * Start filling it up w/ messages. I use '\0' as separator to break up messages.
+ * This is also very handy since we can do printf on message.
+ *
+ * Once the buffer is full we need to get rid of the first message in buffer and
+ * insert the new message. (Note: if the message being added is >1 message then
+ * we will need to "remove" >1 old message from the buffer). The way this is done
+ * is the following:
+ * When we reach the end of the buffer we set a mark and start from the beginning.
+ * Now what about the beginning and end of the buffer? Well we have the "head"
+ * index/pointer which is the starting point for the messages and we have "tail"
+ * index/pointer which is the ending point for the messages. When we "display" the
+ * messages we start from the beginning and continue until we reach "tail". If we
+ * reach end of buffer, then we just start from the beginning (offset 0). "head" and
+ * "tail" are actually offsets from the beginning of the buffer.
+ *
+ * Note: This algorithm uses Linux IPC mechanism w/ shared memory and semaphores to provide
+ * a threasafe way of handling shared memory operations.
+ */
+ if ( (buf->tail + l) < buf->size ){
+ /* before we append the message we need to check the HEAD so that we won't
+ overwrite any of the message that we still need and adjust HEAD to point
+ to the next message! */
+ if ( buf->tail < buf->head){
+ if ( (buf->tail + l) >= buf->head ){
+ /* we need to move the HEAD to point to the next message
+ * Theoretically we have enough room to add the whole message to the
+ * buffer, because of the first outer IF statement, so we don't have
+ * to worry about overflows here!
+ */
+ int k= buf->tail + l - buf->head; /* we need to know how many bytes
+ we are overwriting to make
+ enough room */
+ char *c=memchr(buf->data+buf->head + k,'\0',buf->size - (buf->head + k));
+ if (c != NULL) {/* do a sanity check just in case! */
+ buf->head = c - buf->data + 1; /* we need to convert pointer to
+ offset + skip the '\0' since
+ we need to point to the beginning
+ of the next message */
+ /* Note: HEAD is only used to "retrieve" messages, it's not used
+ when writing messages into our buffer */
+ }else{ /* show an error message to know we messed up? */
+ printf("Weird! Can't find the terminator token??? \n");
+ buf->head=0;
+ }
+ }
+ } /* in other cases no overflows have been done yet, so we don't care! */
+
+ /* we should be ok to append the message now */
+ strncpy(buf->data + buf->tail,msg,l); /* append our message */
+ buf->tail+=l; /* count full message w/ '\0' terminating char */
+ }else{
+ /* we need to break up the message and "circle" it around */
+ char *c;
+ int k=buf->tail + l - buf->size; /* count # of bytes we don't fit */
+
+ /* We need to move HEAD! This is always the case since we are going
+ * to "circle" the message.
+ */
+ c=memchr(buf->data + k ,'\0', buf->size - k);
+
+ if (c != NULL) /* if we don't have '\0'??? weird!!! */{
+ /* move head pointer*/
+ buf->head=c-buf->data+1;
+
+ /* now write the first part of the message */
+ strncpy(buf->data + buf->tail, msg, l - k - 1);
+
+ /* ALWAYS terminate end of buffer w/ '\0' */
+ buf->data[buf->size-1]='\0';
+
+ /* now write out the rest of the string to the beginning of the buffer */
+ strcpy(buf->data, &msg[l-k-1]);
+
+ /* we need to place the TAIL at the end of the message */
+ buf->tail = k + 1;
+ }else{
+ printf("Weird! Can't find the terminator token from the beginning??? \n");
+ buf->head = buf->tail = 0; /* reset buffer, since it's probably corrupted */
+ }
+
+ }
+ sem_up(s_semid);
+}
+#endif
/* Note: There is also a function called "message()" in init.c */
/* Print a message to the log file. */
static void message (char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
@@ -104,6 +267,16 @@
fl.l_start = 0;
fl.l_len = 1;
+#ifdef BB_FEATURE_IPC_SYSLOG
+ if ((circular_logging == TRUE) && (buf != NULL)){
+ char b[1024];
+ va_start (arguments, fmt);
+ vsprintf (b, fmt, arguments);
+ va_end (arguments);
+ circ_message(b);
+
+ }else
+#endif
if ((fd = device_open (logFilePath,
O_WRONLY | O_CREAT | O_NOCTTY | O_APPEND |
O_NONBLOCK)) >= 0) {
@@ -197,6 +370,10 @@
{
logMessage(0, "System log daemon exiting.");
unlink(lfile);
+#ifdef BB_FEATURE_IPC_SYSLOG
+ ipcsyslog_cleanup();
+#endif
+
exit(TRUE);
}
@@ -340,7 +517,7 @@
init_RemoteLog();
}
#endif
-
+
logMessage (0, "syslogd started: BusyBox v" BB_VER " (" BB_BT ")");
for (;;) {
@@ -362,113 +539,26 @@
--n_ready;
if (fd == sock_fd) {
-
int conn;
- pid_t pid;
+ //printf("New Connection request.\n");
if ((conn = accept (sock_fd, (struct sockaddr *) &sunx, &addrLength)) < 0) {
perror_msg_and_die ("accept error");
}
-
- pid = fork();
-
- if (pid < 0) {
- perror ("syslogd: fork");
- close (conn);
- continue;
- }
-
- if (pid == 0) {
- serveConnection (conn);
- close (conn);
- exit( TRUE);
- }
- close (conn);
- }
- }
- }
- }
-}
-
-#ifdef BB_FEATURE_KLOGD
-
-static void klogd_signal(int sig)
-{
- klogctl(7, NULL, 0);
- klogctl(0, 0, 0);
- logMessage(0, "Kernel log daemon exiting.");
- exit(TRUE);
+
+ FD_SET(conn, &fds);
+ //printf("conn: %i, set_size: %i\n",conn,FD_SETSIZE);
+ }else{
+ //printf("Serving connection: %i\n",fd);
+ serveConnection (fd);
+ close (fd);
+ FD_CLR(fd, &fds);
+ } /* fd == sock_fd */
+ }/* FD_ISSET() */
+ }/* for */
+ } /* for main loop */
}
-static void doKlogd (void) __attribute__ ((noreturn));
-static void doKlogd (void)
-{
- int priority = LOG_INFO;
- char log_buffer[4096];
- int i, n, lastc;
- char *start;
-
- /* Set up sig handlers */
- signal(SIGINT, klogd_signal);
- signal(SIGKILL, klogd_signal);
- signal(SIGTERM, klogd_signal);
- signal(SIGHUP, SIG_IGN);
-
-#ifdef BB_FEATURE_REMOTE_LOG
- if (doRemoteLog == TRUE){
- init_RemoteLog();
- }
-#endif
-
- logMessage(0, "klogd started: "
- "BusyBox v" BB_VER " (" BB_BT ")");
-
- /* "Open the log. Currently a NOP." */
- klogctl(1, NULL, 0);
-
- while (1) {
- /* Use kernel syscalls */
- memset(log_buffer, '\0', sizeof(log_buffer));
- n = klogctl(2, log_buffer, sizeof(log_buffer));
- if (n < 0) {
- char message[80];
-
- if (errno == EINTR)
- continue;
- snprintf(message, 79, "klogd: Error return from sys_sycall: " \
- "%d - %s.\n", errno, strerror(errno));
- logMessage(LOG_SYSLOG | LOG_ERR, message);
- exit(1);
- }
-
- /* klogctl buffer parsing modelled after code in dmesg.c */
- start=&log_buffer[0];
- lastc='\0';
- for (i=0; i<n; i++) {
- if (lastc == '\0' && log_buffer[i] == '<') {
- priority = 0;
- i++;
- while (isdigit(log_buffer[i])) {
- priority = priority*10+(log_buffer[i]-'0');
- i++;
- }
- if (log_buffer[i] == '>') i++;
- start = &log_buffer[i];
- }
- if (log_buffer[i] == '\n') {
- log_buffer[i] = '\0'; /* zero terminate this message */
- logMessage(LOG_KERN | priority, start);
- start = &log_buffer[i+1];
- priority = LOG_INFO;
- }
- lastc = log_buffer[i];
- }
- }
-
-}
-
-#endif
-
static void daemon_init (char **argv, char *dz, void fn (void))
{
setsid();
@@ -480,16 +570,13 @@
extern int syslogd_main(int argc, char **argv)
{
- int opt, pid, klogd_pid;
+ int opt, pid;
int doFork = TRUE;
-#ifdef BB_FEATURE_KLOGD
- int startKlogd = TRUE;
-#endif
char *p;
/* do normal option parsing */
- while ((opt = getopt(argc, argv, "m:nKO:R:L")) > 0) {
+ while ((opt = getopt(argc, argv, "m:nO:R:LC")) > 0) {
switch (opt) {
case 'm':
MarkInterval = atoi(optarg) * 60;
@@ -497,11 +584,6 @@
case 'n':
doFork = FALSE;
break;
-#ifdef BB_FEATURE_KLOGD
- case 'K':
- startKlogd = FALSE;
- break;
-#endif
case 'O':
logFilePath = strdup(optarg);
break;
@@ -518,6 +600,11 @@
local_logging = TRUE;
break;
#endif
+#ifdef BB_FEATURE_IPC_SYSLOG
+ case 'C':
+ circular_logging = TRUE;
+ break;
+#endif
default:
show_usage();
}
@@ -529,6 +616,7 @@
local_logging = TRUE;
#endif
+
/* Store away localhost's name before the fork */
gethostname(LocalHostName, sizeof(LocalHostName));
if ((p = strchr(LocalHostName, '.'))) {
@@ -537,13 +625,9 @@
umask(0);
-#ifdef BB_FEATURE_KLOGD
- /* Start up the klogd process */
- if (startKlogd == TRUE) {
- klogd_pid = fork();
- if (klogd_pid == 0) {
- daemon_init (argv, "klogd", doKlogd);
- }
+#ifdef BB_FEATURE_IPC_SYSLOG
+ if (circular_logging == TRUE ){
+ ipcsyslog_init();
}
#endif
Index: usage.h
===================================================================
RCS file: /var/cvs/busybox/usage.h,v
retrieving revision 1.14
diff -u -r1.14 usage.h
--- usage.h 2001/03/02 19:08:50 1.14
+++ usage.h 2001/03/07 19:13:29
@@ -451,6 +451,13 @@
"Options:\n" \
"\t-l\tList all signal names and numbers."
+#define klogd_trivial_usage \
+ "-n"
+#define klogd_full_usage \
+ "Kernel logger.\n"\
+ "Options:\n"\
+ "\t-n\tRun as a foreground process."
+
#define length_trivial_usage \
"STRING"
#define length_full_usage \
@@ -496,6 +503,12 @@
#define logname_full_usage \
"Print the name of the current user."
+#define logread_trivial_usage \
+ ""
+
+#define logread_full_usage \
+ "Shows the messages from syslogd (using circular buffer)."
+
#ifdef BB_FEATURE_LS_TIMESTAMPS
#define USAGE_LS_TIMESTAMPS(a) a
#else
@@ -896,11 +909,6 @@
"Write all buffered filesystem blocks to disk."
-#ifdef BB_FEATURE_KLOGD
- #define USAGE_KLOGD(a) a
-#else
- #define USAGE_KLOGD(a)
-#endif
#ifdef BB_FEATURE_REMOTE_LOG
#define USAGE_REMOTE_LOG(a) a
#else
@@ -909,12 +917,11 @@
#define syslogd_trivial_usage \
"[OPTION]..."
#define syslogd_full_usage \
- "Linux system and kernel (provides klogd) logging utility.\n" \
- "Note that this version of syslogd/klogd ignores /etc/syslog.conf.\n\n" \
+ "Linux system and kernel logging utility.\n" \
+ "Note that this version of syslogd ignores /etc/syslog.conf.\n\n" \
"Options:\n" \
"\t-m NUM\t\tInterval between MARK lines (default=20min, 0=off)\n" \
"\t-n\t\tRun as a foreground process\n" \
- USAGE_KLOGD("\t-K\t\tDo not start up the klogd process\n") \
"\t-O FILE\t\tUse an alternate log file (default=/var/log/messages)" \
USAGE_REMOTE_LOG( \
"\n\t-R HOST[:PORT]\tLog to IP or hostname on PORT (default PORT=514/UDP)\n" \
Index: utility.c
===================================================================
RCS file: /var/cvs/busybox/utility.c,v
retrieving revision 1.216
diff -u -r1.216 utility.c
--- utility.c 2001/03/06 19:35:58 1.216
+++ utility.c 2001/03/07 19:13:31
@@ -77,6 +77,10 @@
# endif
#endif
+#if defined(BB_KLOGD) || defined(BB_LOGGER)
+#include <syslog.h>
+#endif
+
static struct BB_applet *applet_using;
extern void show_usage(void)
@@ -1847,6 +1851,20 @@
if (s[len-1] == '\n')
s[len-1] = '\0';
+}
+#endif
+
+#if defined(BB_KLOGD) || defined(BB_LOGGER)
+void syslog_msg_with_name(const char *name, int facility, int pri, const char *msg)
+{
+ openlog(name, 0, facility);
+ syslog(pri, "%s", msg);
+ closelog();
+}
+
+void syslog_msg(int facility, int pri, const char *msg)
+{
+ syslog_msg_with_name(applet_using->name, facility, pri, msg);
}
#endif
-------------- next part --------------
/* vi: set sw=4 ts=4: */
/*
* circular buffer syslog implementation for busybox
*
* Copyright (C) 2000 by Gennady Feldman <gfeldman at cachier.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/types.h>
#include <sys/sem.h>
#include <sys/shm.h>
#include <signal.h>
#include <setjmp.h>
#include "busybox.h"
static const long KEY_ID = 0x414e4547; /*"GENA"*/
static struct shbuf_ds {
int size; // size of data written
int head; // start of message list
int tail; // end of message list
char data[1]; // data/messages
} *buf = NULL; // shared memory pointer
// Semaphore operation structures
static struct sembuf SMrup[1] = {{0, -1, IPC_NOWAIT | SEM_UNDO}}; // set SMrup
static struct sembuf SMrdn[2] = {{1, 0}, {0, +1, SEM_UNDO}}; // set SMrdn
static int shmid = -1; // ipc shared memory id
static int semid = -1; // ipc semaphore id
static jmp_buf jmp_env;
static void error_exit(const char *str);
static void interrupted(int sig);
/*
* sem_up - up()'s a semaphore.
*/
static inline void sem_up(int semid)
{
if ( semop(semid, SMrup, 1) == -1 )
error_exit("semop[SMrup]");
}
/*
* sem_down - down()'s a semaphore
*/
static inline void sem_down(int semid)
{
if ( semop(semid, SMrdn, 2) == -1 )
error_exit("semop[SMrdn]");
}
extern int logread_main(int argc, char **argv)
{
int i;
/* no options, no getopt */
if (argc > 1)
show_usage();
// handle intrrupt signal
if (setjmp(jmp_env)) goto output_end;
// attempt to redefine ^C signal
signal(SIGINT, interrupted);
if ( (shmid = shmget(KEY_ID, 0, 0)) == -1)
error_exit("Can't find circular buffer");
// Attach shared memory to our char*
if ( (buf = shmat(shmid, NULL, SHM_RDONLY)) == NULL)
error_exit("Can't get access to circular buffer from syslogd");
if ( (semid = semget(KEY_ID, 0, 0)) == -1)
error_exit("Can't get access to semaphone(s) for circular buffer from syslogd");
sem_down(semid);
// Read Memory
i=buf->head;
//printf("head: %i tail: %i size: %i\n",buf->head,buf->tail,buf->size);
if (buf->head == buf->tail) {
printf("<empty syslog>\n");
}
while ( i != buf->tail) {
printf("%s", buf->data+i);
i+= strlen(buf->data+i) + 1;
if (i >= buf->size )
i=0;
}
sem_up(semid);
output_end:
if (shmid != -1)
shmdt(buf);
return EXIT_SUCCESS;
}
static void interrupted(int sig){
signal(SIGINT, SIG_IGN);
longjmp(jmp_env, 1);
}
static void error_exit(const char *str){
perror(str);
//release all acquired resources
if (shmid != -1)
shmdt(buf);
exit(1);
}
-------------- next part --------------
/* vi: set sw=4 ts=4: */
/*
* Mini klogd implementation for busybox
*
* Copyright (C) 2001 by Gennady Feldman <gfeldman at cachier.com>.
* Changes: Made this a standalone busybox module which uses standalone
* syslog() client interface.
*
* Copyright (C) 1999,2000,2001 by Lineo, inc.
* Written by Erik Andersen <andersen at lineo.com>, <andersee at debian.org>
*
* Copyright (C) 2000 by Karl M. Hegbloom <karlheg at debian.org>
*
* "circular buffer" Copyright (C) 2000 by Gennady Feldman <gfeldman at mail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <signal.h> /* for our signal() handlers */
#include <string.h> /* strncpy() */
#include <errno.h> /* errno and friends */
#include <unistd.h>
#include <ctype.h>
#include <sys/syslog.h>
#if ! defined __GLIBC__ && ! defined __UCLIBC__
#include <sys/syscall.h>
#include <linux/unistd.h>
typedef unsigned int socklen_t;
#ifndef __alpha__
# define __NR_klogctl __NR_syslog
static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
#else /* __alpha__ */
#define klogctl syslog
#endif
#else
# include <sys/klog.h>
#endif
#include "busybox.h"
static void klogd_signal(int sig)
{
klogctl(7, NULL, 0);
klogctl(0, 0, 0);
//logMessage(0, "Kernel log daemon exiting.");
syslog_msg(LOG_DAEMON, 0, "Kernel log daemon exiting.");
exit(TRUE);
}
static void doKlogd (void) __attribute__ ((noreturn));
static void doKlogd (void)
{
int priority = LOG_INFO;
char log_buffer[4096];
int i, n, lastc;
char *start;
/* Set up sig handlers */
signal(SIGINT, klogd_signal);
signal(SIGKILL, klogd_signal);
signal(SIGTERM, klogd_signal);
signal(SIGHUP, SIG_IGN);
/* "Open the log. Currently a NOP." */
klogctl(1, NULL, 0);
syslog_msg(LOG_DAEMON, 0, "klogd started: BusyBox v" BB_VER " (" BB_BT ")");
while (1) {
/* Use kernel syscalls */
memset(log_buffer, '\0', sizeof(log_buffer));
n = klogctl(2, log_buffer, sizeof(log_buffer));
if (n < 0) {
char message[80];
if (errno == EINTR)
continue;
snprintf(message, 79, "klogd: Error return from sys_sycall: %d - %s.\n",
errno, strerror(errno));
syslog_msg(LOG_DAEMON, LOG_SYSLOG | LOG_ERR, message);
exit(1);
}
/* klogctl buffer parsing modelled after code in dmesg.c */
start=&log_buffer[0];
lastc='\0';
for (i=0; i<n; i++) {
if (lastc == '\0' && log_buffer[i] == '<') {
priority = 0;
i++;
while (isdigit(log_buffer[i])) {
priority = priority*10+(log_buffer[i]-'0');
i++;
}
if (log_buffer[i] == '>') i++;
start = &log_buffer[i];
}
if (log_buffer[i] == '\n') {
log_buffer[i] = '\0'; /* zero terminate this message */
syslog_msg(LOG_DAEMON, LOG_KERN | priority, start);
start = &log_buffer[i+1];
priority = LOG_INFO;
}
lastc = log_buffer[i];
}
}
}
static void daemon_init (char **argv, char *dz, void fn (void))
{
setsid(); /* start a new session? */
strncpy(argv[0], dz, strlen(argv[0]));
fn();
exit(0);
}
extern int klogd_main(int argc, char **argv)
{
/* no options, no getopt */
int opt, pid;
int doFork = TRUE;
/* do normal option parsing */
while ((opt = getopt(argc, argv, "n")) > 0) {
switch (opt) {
case 'n':
doFork = FALSE;
break;
default:
show_usage();
}
}
if (doFork == TRUE) {
pid = fork();
if (pid < 0)
exit(pid);
else if (pid == 0) {
daemon_init (argv, "klogd", doKlogd);
}
} else {
doKlogd();
}
return EXIT_SUCCESS;
}
/*
Local Variables
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/
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