usyslogd - microsyslogd that has a hard-coded configuration (read from

/dev/klog and write to /var/log/messages). It's written so that more
sources and outputs could be added easily though.

commands/simple/Makefile

@@ -187,6 +187,7 @@ ALL	= \
 	update \
 	uud \
 	uue \
+	usyslogd \
 	vol \
 	wc \
 	which \
@@ -792,6 +793,10 @@ uud:	uud.c
 	$(CCLD) -o $@ $?
 	@install -S 4kw $@
 
+usyslogd:	usyslogd.c
+	$(CCLD) -o $@ $?
+	@install -S 4kw $@
+
 uue:	uue.c
 	$(CCLD) -o $@ $?
 	@install -S 4kw $@
@@ -1010,6 +1015,7 @@ install:	\
 		/usr/bin/uudecode \
 	/usr/bin/uue \
 		/usr/bin/uuencode \
+	/usr/bin/usyslogd \
 	/usr/bin/vol \
 	/usr/bin/wc \
 	/usr/bin/which \
@@ -1532,6 +1538,9 @@ install:	\
 /usr/bin/uudecode:	/usr/bin/uud
 	install -l $? $@
 
+/usr/bin/usyslogd:	usyslogd
+	install -cs -o bin $? $@
+
 /usr/bin/uue:	uue
 	install -cs -o bin $? $@
 

commands/simple/usyslogd.c

@@ -0,0 +1,105 @@
+/* Microsyslogd that does basic syslogging.
+ */
+
+#include <stdio.h>
+#include <sys/select.h>
+#include <sys/utsname.h>
+#include <sys/types.h>
+#include <time.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+
+char *nodename;
+
+void logline(FILE *outfp, char *proc, char *line)
+{
+	time_t now;
+	struct tm *tm;
+	char *d, *s;
+	time(&now);
+	tm = localtime(&now);
+	d=asctime(tm);
+
+	/* Trim off year and newline. */
+	if((s=strrchr(d, ' ')))
+		*s = '\0';
+	fprintf(outfp, "%s %s kernel: %s\n", d, nodename, line);
+}
+
+void copy(int in_fd, FILE *outfp)
+{
+	static char linebuf[5*1024];
+	int l, acc = 0;
+	while((l=read(in_fd, linebuf, sizeof(linebuf)-2)) > 0) {
+		char *b, *eol;
+		int i;
+		acc += l;
+		for(i = 0; i < l; i++)
+			if(linebuf[i] == '\0')
+				linebuf[i] = ' ';
+		if(linebuf[l-1] == '\n') l--;
+		linebuf[l] = '\n';
+		linebuf[l+1] = '\0';
+		b = linebuf;
+		while(eol = strchr(b, '\n')) {
+			*eol = '\0';
+			logline(outfp, "kernel", b);
+			b = eol+1;
+		}
+	}
+
+	/* Nothing sensible happened? Avoid busy-looping. */
+	if(!acc) sleep(1);
+
+	return;
+}
+
+int
+main(int argc, char *argv[])
+{
+	int config_fd, klog_fd, n, maxfd;
+	char *nn;
+	FILE *logfp;
+	struct utsname utsname;
+
+	if(uname(&utsname) < 0) {
+		perror("uname");
+		return 1;
+	}
+
+	nodename = utsname.nodename;
+	if((nn=strchr(nodename, '.')))
+		*nn = '\0';
+
+	if((klog_fd = open("/dev/klog", O_NONBLOCK | O_RDONLY)) < 0) {
+		perror("/dev/klog");
+		return 1;
+	}
+
+	if(!(logfp = fopen("/var/log/messages", "a"))) {
+		perror("/var/log/messages");
+		return 1;
+	}
+
+	maxfd = klog_fd;
+
+	while(1) {
+		fd_set fds;
+		FD_ZERO(&fds);
+		FD_SET(klog_fd, &fds);
+		n = select(maxfd+1, &fds, NULL, NULL, NULL);
+		if(n <= 0) {
+			sleep(1);
+			continue;
+		}
+		if(FD_ISSET(klog_fd, &fds)) {
+			copy(klog_fd, logfp);
+		}
+		fflush(logfp);
+	}
+
+	return 0;
+}
+