sysvinit/showconsole-1.10.dif

--- Makefile
+++ Makefile	2010-05-28 14:15:39.662925024 +0000
@@ -62,7 +62,7 @@ TODO	=	showconsole blogd blogger isseria
 all: $(TODO)
 
 libconsole.o:	libconsole.c libconsole.h
-	$(CC) $(CFLAGS) $(CLOOP) -c $< -pthread
+	$(CC) $(CFLAGS) $(CLOOP) -D_REENTRANT -c $< -pthread
 
 libblogger.o:	libblogger.c libblogger.h
 	$(CC) $(CFLAGS) $(CLOOP) -c $<
@@ -74,7 +74,7 @@ showconsole:	showconsole.c libconsole.o
 	$(CC) $(CFLAGS) $(CLOOP) -o $@ $^ -Wl,--as-needed -pthread
 
 blogd:	blogd.c libconsole.o
-	$(CC) $(CFLAGS) $(CLOOP) -o $@ $^ -Wl,--as-needed -lutil -pthread
+	$(CC) $(CFLAGS) $(CLOOP) -D_REENTRANT -o $@ $^ -Wl,--as-needed -lutil -pthread
 
 blogger:	blogger.c libblogger.a
 	$(CC) $(CFLAGS) $(CLOOP) -o $@ $^
--- blogd.8
+++ blogd.8	2010-05-04 09:57:15.679656772 +0000
@@ -58,6 +58,13 @@ that now it is able to write on
 which means that the file system is
 mounted read/write and the kernel
 messages are written to that file.
+.TP
+.B SIGSYS
+says
+.B blogd
+that it should stop writing to disk but
+continue to repeat messages to the old
+devices of the system console.
 \."
 .SH BUGS
 .B blogd
--- blogd.c
+++ blogd.c	2010-05-28 14:31:23.748444849 +0000
@@ -24,6 +24,7 @@
 #include <errno.h>
 #include <paths.h>
 #include "libconsole.h"
+extern volatile sig_atomic_t nsigsys;
 
 /*
  * Internal logger
@@ -102,11 +103,22 @@ static struct sigaction saved_sighup;
 static struct sigaction saved_sigint;
 static struct sigaction saved_sigquit;
 static struct sigaction saved_sigterm;
+static struct sigaction saved_sigsys;
 static volatile sig_atomic_t signaled = 0;
 
 static void sighandle(int sig)
 {
-    signaled = sig;
+    if (nsigsys && (sig == SIGTERM))
+	return;
+    signaled = (volatile sig_atomic_t)sig;
+}
+
+/*
+ * Stop writing logs to disk, only repeat messages
+ */
+static void sigsys(int sig)
+{
+    nsigsys = (volatile sig_atomic_t)sig;
 }
 
 static void set_signal(int sig, struct sigaction *old, sighandler_t handler)
@@ -116,7 +128,7 @@ static void set_signal(int sig, struct s
 	    break;
     } while (errno == EINTR);
 
-    if (old->sa_handler != handler) {
+    if (old && old->sa_handler != handler) {
 	struct sigaction new;
 	sigset_t sigset;
 
@@ -143,7 +155,7 @@ static void reset_signal(int sig, struct
 	    break;
     } while (errno == EINTR);
 
-    if (old->sa_handler == cur.sa_handler) {
+    if (old && old->sa_handler == cur.sa_handler) {
 	do {
 	    if (sigaction(sig, old, NULL) == 0)
 		break;
@@ -320,6 +332,7 @@ int main(int argc, char *argv[])
     if (ioctl(pts, TIOCCONS, NULL) < 0)
 	error("can not set console device to %s: %s\n", ptsname, strerror(errno));
 
+    nsigsys = 0;
     set_signal(SIGTTIN, &saved_sigttin, SIG_IGN);
     set_signal(SIGTTOU, &saved_sigttou, SIG_IGN);
     set_signal(SIGTSTP, &saved_sigtstp, SIG_IGN);
@@ -327,9 +340,11 @@ int main(int argc, char *argv[])
     set_signal(SIGINT,  &saved_sigint,  sighandle);
     set_signal(SIGQUIT, &saved_sigquit, sighandle);
     set_signal(SIGTERM, &saved_sigterm, sighandle);
+    set_signal(SIGSYS,  &saved_sigsys,  sigsys);
     (void)siginterrupt(SIGINT,  0);
     (void)siginterrupt(SIGQUIT, 0);
     (void)siginterrupt(SIGTERM, 0);
+    (void)siginterrupt(SIGSYS,  0);
 
     switch ((pid = fork())) {
     case 0:
@@ -364,11 +379,22 @@ int main(int argc, char *argv[])
 	fflush(stdout);
 	exit(0);
     }
-    pidfile();
-    prepareIO(reconnect, pgrp, 0, 1, fd2);
+
+    prepareIO(reconnect, pidfile, pgrp, 0, 1, fd2);
     while (!signaled)
 	safeIO();
 
+    (void)tcdrain(1);
+    (void)tcdrain(2);
+    if (fd2 > 0)
+	(void)tcdrain(fd2);
+
+    errno = 0;
+    if ((fd = open("/dev/console", O_RDWR|O_NOCTTY)) >= 0) {
+	(void)ioctl(fd, TIOCCONS, NULL);	/* Restore old console mapping */
+	close(fd);
+    }
+
     if (!cntrtty)
 	kill(ppid, SIGSTOP);
     closeIO();
@@ -394,6 +420,7 @@ int main(int argc, char *argv[])
     reset_signal(SIGINT,  &saved_sigint);
     reset_signal(SIGQUIT, &saved_sigquit);
     reset_signal(SIGTERM, &saved_sigterm);
+    reset_signal(SIGSYS,  &saved_sigsys);
 
     return 0;
 }
--- libconsole.c
+++ libconsole.c	2010-05-28 13:57:01.458924791 +0000
@@ -155,7 +155,7 @@ out:
 /*
  * Arg used: safe out
  */
-static void (*vc_reconnect)(int fd) = NULL;
+static void (*vc_reconnect)(int fd);
 static inline void safeout (int fd, const char *ptr, size_t s)
 {
     int saveerr = errno;
@@ -291,6 +291,7 @@ static int fdfifo  = -1;
 /*
  * Signal control for writing on log file
  */
+volatile sig_atomic_t nsigsys = 0;
 static volatile sig_atomic_t nsigio = -1;
 static sigset_t save_oldset;
 
@@ -382,7 +383,7 @@ xout:
 static inline void writelog(void)
 {
     if (!flog)
-	goto xout;;
+	goto xout;
     clearerr(flog);
     lock(&llock);
     while (avail > 0) {
@@ -715,6 +716,7 @@ static void *action(void *dummy)
     sigaddset(&sigset, SIGINT);
     sigaddset(&sigset, SIGQUIT);
     sigaddset(&sigset, SIGTERM);
+    sigaddset(&sigset, SIGSYS);
     (void)pthread_sigmask(SIG_BLOCK, &sigset, &save_oldset);
 
     lock(&ljoin);
@@ -739,11 +741,13 @@ static void *action(void *dummy)
  * Prepare I/O
  */
 static const char *fifo_name = _PATH_BLOG_FIFO;
+static void (*vr_access)(void);
 static pid_t pgroup = -1;
 
-void prepareIO(void (*rfunc)(int), const pid_t pgrp, const int in, const int out, const int second)
+void prepareIO(void (*rfunc)(int), void (*pfunc)(void), const pid_t pgrp, const int in, const int out, const int second)
 {
     vc_reconnect = rfunc;
+    vr_access = pfunc;
     pgroup  = pgrp;
     fdread  = in;
     fdwrite = out;
@@ -871,6 +875,10 @@ void safeIO (void)
 		error("Can not open %s: %s\n", BOOT_LOGFILE, STRERR);
 	    goto skip;
 	}
+	if (vr_access) {
+	    (*vr_access)();
+	    vr_access = NULL;
+	}
 	if ((flog = fdopen (log, "a")) == NULL)
 		error("Can not open %s: %s\n", BOOT_LOGFILE, STRERR);
 
@@ -915,6 +923,15 @@ skip:
 	pthread_setschedparam(pthread_self(), policy, &param);
 	pthread_setschedparam(lthread, policy, &param);
     }
+
+    if (nsigsys) {  /* Stop writing logs to disk, only repeat messages */
+	if (flog)
+	    closeIO();
+	if (nsigio < 0) {
+	    nsigio = SIGIO;
+	    (void)signal(SIGIO, SIG_IGN);
+	}
+    }
 }
 
 /*
@@ -926,11 +943,9 @@ void closeIO(void)
     int n = 240;
 
     /* Maybe we've catched a signal, therefore */
-    if (flog) {
-	fflush(flog);			/* Clear out stdio buffers   */
-	fdatasync(fileno(flog));
-    } else
+    if (!flog && !nsigsys)
 	warn("no message logging because /var file system is not accessible\n");
+
     (void)tcdrain(fdwrite);		/* Hold in sync with console */
     if (fdsec > 0)
 	(void)tcdrain(fdsec);		/* Hold in sync with second console */
@@ -949,9 +964,8 @@ void closeIO(void)
 	timeout.tv_usec = 25*1000;
 
     	more_input(&timeout, 1);
+	(void)tcdrain(fdread);
 
-	if (!flog)
-	    break;
     } while (timeout.tv_sec || timeout.tv_usec);
 
     if (running) {
--- libconsole.h
+++ libconsole.h	2009-12-21 14:54:41.299449887 +0000
@@ -2,6 +2,6 @@ extern void pushd(const char * path);
 extern void popd(void);
 extern char * fetchtty(const pid_t pid, const pid_t ppid, unsigned int *mjmi);
 extern char * secondtty(char * compare);
-extern void prepareIO(void (*rfunc)(int), const pid_t pgrp, const int in, const int out, const int second);
+extern void prepareIO(void (*rfunc)(int), void (*pfunc)(void), const pid_t pgrp, const int in, const int out, const int second);
 extern void safeIO (void);
 extern void closeIO(void);