[RELEASE] flxutils-0.1.23v0.1.23

7 files changed, 198 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 2e46b2d..91e58f4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -63,3 +63,7 @@
  - wdd now also does a 'stat("/")' which is useful in case of broken NFSROOT.
  - a new deployment script for wdd
 
+2004/08/06
+ - now 'wdd' supports checks of arbitrary file lists and gets a man page.
+ - lcdwrite and lcdtee sources have been brought back
+
diff --git a/lcd/Makefile b/lcd/Makefile
new file mode 100644
index 0000000..06e0926
--- /dev/null
+++ b/lcd/Makefile
@@ -0,0 +1,9 @@
+OBJS=lcdwrite lcdtee
+include ../include/rules.make
+CFLAGS+=-fomit-frame-pointer
+
+%:	%.c
+	$(CC) $(LDFLAGS) $(CFLAGS) -o $@ $<
+	strip -R .comment -R .note $@
+	objdump -h $@ | grep -q '\.data[ ]*00000000' && strip -R .data $@ || true
+	sstrip $@
diff --git a/lcd/lcdtee.c b/lcd/lcdtee.c
new file mode 100644
index 0000000..2cab2ef
--- /dev/null
+++ b/lcd/lcdtee.c
@@ -0,0 +1,21 @@
+/* simply write all args to /dev/lcd, and don't complain if it doesn't work */
+#include <sys/fcntl.h>
+
+main(int argc, char **argv) {
+  int fd;
+  char buf[1024];
+  int len;
+
+  fd = open("/dev/lcd", O_WRONLY);
+
+  while ((len = read(0, buf, sizeof(buf))) > 0) {
+		write(1, buf, len);
+		if (fd > 0)
+			write(fd, buf, len);
+  }
+
+  if (fd > 0)
+	close(fd);
+  return 0;
+}
+
diff --git a/lcd/lcdwrite.c b/lcd/lcdwrite.c
new file mode 100644
index 0000000..5f86c46
--- /dev/null
+++ b/lcd/lcdwrite.c
@@ -0,0 +1,34 @@
+/* simply write all args to /dev/lcd, and don't complain if it doesn't work */
+#include <sys/fcntl.h>
+
+main(int argc, char **argv) {
+  int fd;
+  char buf[1024];
+  int len;
+
+
+  if ((fd = open("/dev/lcd", O_WRONLY)) == -1)
+	return 0;
+
+
+  if (--argc == 0) {
+	while ((len = read(0, buf, sizeof(buf))) > 0)
+		write(fd, buf, len);
+  }
+  else {
+	argv++;
+
+	while (argc--) {
+		len = strlen(*argv);
+		if (argc) /* still other args */
+			argv[0][len++]=' '; /* add a delimitor */
+		else
+			argv[0][len++]='\n'; /* end with a newline */
+		write(fd, *argv, len);
+		argv++;
+	}
+  }
+  close(fd);
+  return 0;
+}
+
diff --git a/remount/remountw b/remount/remountw
deleted file mode 120000
index 5bc7a05..0000000
--- a/remount/remountw
+++ /dev/null
@@ -1 +0,0 @@
-remountr
\ No newline at end of file
diff --git a/wd/wdd.8 b/wd/wdd.8
new file mode 100644
index 0000000..9d56386
--- /dev/null
+++ b/wd/wdd.8
@@ -0,0 +1,85 @@
+.TH wdd "8" "August 2004" "wdd (flxutils) 0.1.23"  "Simple Watchdog Daemon"
+.SH NAME
+wdd - Simple Watchdog Daemon
+.SH SYNOPSIS
+.B wdd [file]...
+.SH DESCRIPTION
+Wdd is a simple daemon which periodically pings the watchdog attached
+to /dev/watchdog to keep it alive, and parallely performs a series of
+system health checks to ensure everything is working correctly. If it
+detects an error, it exits so that the watchdog driver doesn't receive
+its keep-alives anymore and the system will quickly reboot. It is
+particularly targetted at remotely managed systems where accessibility
+is a prior concern.
+
+As a bonus, it's really tiny, it consumes between 12 and 20 kB of
+memory on x86.
+
+It can optionnally take a list of files in arguments. These files will
+be checked upon startup, and all those which are accessible will be
+periodically checked (one file per second) and the daemon will exit
+as soon as it cannot access any of them. This is particularly useful
+on \fB/dev\fP, \fB/var\fP, \fB/tmp\fP, \fB/proc\fP and more generally
+any remotely mounted file-system (including \fB/\fP in case of NFS
+root). As a special case, all files which are not accessible at
+startup are removed from the tests and get their first character
+rewritten with a '\fB!\fP' in the argument list, so that they become
+easily identifiable with \fBps\fP.
+
+.SH SYSTEM CHECKS
+System checks are performed in this order :
+.LP
+.TP
+\- Opening of \fB/dev/watchdog\fP if it was not previously open ;
+.TP
+\- Allocation then release of 4 kB of memory to check that the VM
+subsystem is still operating, and to give the daemon a chance to die
+under Out-of-Memory conditions (OOM) ;
+.TP
+\- Fork a child and wait for its immediate death. This ensures that the
+system still has free PIDs and some memory, can schedule, and can
+deliver signals.
+.TP
+\- File access on the next file in the argument list. Once the last one
+has been checked, the check loops back to the first one. If no
+argument was given, a test is performed on \fB/\fP to ensure that the
+VFS still works and that an eventual NFS root is still accessible.
+.TP
+\- The daemon then pauses one second before starting the checks again.
+
+.SH FILES
+.TP
+\fB/sbin/wdd\fP
+.br
+The daemon itself
+
+.SH EXAMPLES
+.LP
+.TP
+\fBnice -n 10 /sbin/wdd\fP
+.br
+Starts the daemon with a +10 renice value, and checks the
+accessibility of the root directory every second. Launching it with
+\fBnice\fP is recommended since it makes it more sensible to fork
+bombs because it soon will not get enough time slices to ping the
+driver.
+.TP
+\fBwdd / /dev/watchdog /proc/version /var/run /tmp/.
+.br
+Periodically checks all of these existing entries. This ensures that
+\fB/\fP is always reachable, that \fB/dev\fP has not been wiped out
+nor experienced a mount or unmount, that \fB/proc\fP is mounted, that
+\fB/var\fP is mounted and has not been wiped out, and that \fB/tmp\fP
+either is mounted or is a symbolic link to a valid directory. 
+
+.SH BUGS
+.LP
+.TP
+The daemon cannot renice itself, for this you need the 'nice' command.
+.TP
+There's absolutely no output, neither debug nor error.
+
+.SH SEE ALSO
+\fIDocumentation/watchdog-api.txt\fP in the Linux kernel sources.
+.SH AUTHORS
+Willy Tarreau <willy@meta-x.org>
diff --git a/wd/wdd.c b/wd/wdd.c
index d521881..8481529 100644
--- a/wd/wdd.c
+++ b/wd/wdd.c
@@ -44,25 +44,51 @@ static inline void try_fork() {
 
 
 /*
- * This function checks if the system can access its root FS
- * In case of failure, we exit so that the watchdog device
- * notices it and can reboot.
+ * This function checks if the system can stat a given directory entry on the
+ * VFS. In case of failure, we either report the problem, or exit so that the
+ * watchdog device notices it and can reboot.
  */
-static inline void try_stat() {
+static inline int try_stat(const char *file, int do_exit) {
     void *heap;
+    int ret;
 
     heap = (void*)sbrk(NULL);
     if (brk(heap + sizeof (struct stat)))
 	exit(1);
     memset(heap, 0, sizeof (struct stat));
-    if (stat(root_str, heap) == -1)
-	exit(1);
+    ret =  stat(file, heap);
     if (brk(heap))
 	exit(1);
+
+    if (ret == -1) {
+	if (do_exit)
+	    exit(1);
+	else
+	    return 0;
+    }
+    return 1;
 }
 
-int main (void) {
+int main (int argc, char **argv) {
     int dev;
+    int curr_file;
+
+    if (argc > 1) {
+	/* we'll do a quick check on all the arguments to
+	 * ensure that they are valid at load time, and avoid
+	 * an accidental start of the watchdog which could be
+	 * a disaster in case of a file name error.
+	 */
+	for (curr_file = 1; curr_file < argc; ) {
+	    if (try_stat(argv[curr_file], 0))
+		curr_file++;
+	    else {
+		/* remove this file from the list, and make it noticeable from 'ps' */
+		*argv[curr_file] = '!';
+		argv[curr_file] = argv[--argc];
+	    }
+	}
+    }
 
     if (fork() > 0)
 	return 0;
@@ -70,6 +96,8 @@ int main (void) {
 	close(dev);
     chdir(root_str);
     setsid();
+
+    curr_file = 1; /* start with first file in the list */
     /* let's try indefinitely to open the watchdog device */
     /* note that dev is -1 now ;-) */
     while (1) {
@@ -82,7 +110,16 @@ int main (void) {
 	}
 	try_malloc();
 	try_fork();
-	try_stat();
+
+	if (argc > 1) {
+	    try_stat(argv[curr_file], 1);
+	    curr_file++;
+	    if (curr_file >= argc)
+		curr_file = 1;
+	} else {
+	    try_stat(root_str, 1);
+	}
+
 	/* avoid a fast loop */
 	sleep(1);
     }