jonathan@comp.vuw.ac.nz (Jonathan) (10/06/88)
Enclosed are fixes for two Amoeba problems. They are applicable to
either 1.3b or 1.3c. I mailed these to Dr. Tanenbaum months ago; it
seems he never got them.
Client3.c as posted never worked for me; the context diff below
fixes the bogus parentheses.
Master.c misbehaves chronically if for some reason the exec in its
child fails. It produced an error message, the child exited, and
then master creates a new child whose exec fails...
The error messages came so rapidly I couldn't do *anything*, and had
to cycle the power. The replacement master.c avoids the problem by
waiting after a failed exec.
Enjoy - Jonathan.
#! /bin/sh
# This is a shell archive, meaning:
# 1. Remove everything above the #! /bin/sh line.
# 2. Save the resulting text in a file.
# 3. Execute the file with /bin/sh (not csh) to create the files:
# client3.c.cdif
# master.c
# master.c~
# This archive created: Thu Oct 6 13:28:50 1988
# By: Jonathan ()
export PATH; PATH=/bin:$PATH
echo shar: extracting "'client3.c.cdif'" '(791 characters)'
if test -f 'client3.c.cdif'
then
echo shar: will not over-write existing file "'client3.c.cdif'"
else
sed 's/^X//' << \SHAR_EOF > 'client3.c.cdif'
X*** client3.c.orig Wed Aug 24 20:58:45 1988
X--- client3.c Wed Aug 24 21:54:13 1988
X***************
X*** 140,146 ****
X if (n < 0) {errno = EIO; return(ER);}
X if (hdr2.h_extra != 0) errno = hdr2.h_extra;
X pos[fd] += hdr2.h_status; /* advance file position */
X! return(hdr2.h_status);
X }
X
X
X--- 140,146 ----
X if (n < 0) {errno = EIO; return(ER);}
X if (hdr2.h_extra != 0) errno = hdr2.h_extra;
X pos[fd] += hdr2.h_status; /* advance file position */
X! return((int) hdr2.h_status);
X }
X
X
X***************
X*** 225,231 ****
X }
X
X do {
X! if ((n=read(fd1, b, 1024) < 0)) {
X printf("Cannot read %s\n", argv[1]);
X exit(1);
X }
X--- 225,231 ----
X }
X
X do {
X! if ((n=read(fd1, b, 1024)) < 0) {
X printf("Cannot read %s\n", argv[1]);
X exit(1);
X }
SHAR_EOF
if test 791 -ne "`wc -c < 'client3.c.cdif'`"
then
echo shar: error transmitting "'client3.c.cdif'" '(should have been 791 characters)'
fi
fi # end of overwriting check
echo shar: extracting "'master.c'" '(1454 characters)'
if test -f 'master.c'
then
echo shar: will not over-write existing file "'master.c'"
else
sed 's/^X//' << \SHAR_EOF > 'master.c'
X#include <signal.h>
X
Xchar console[] = "/dev/tty0"; /* no "/dev/console" on Minix */
X
Xrun(uid, gid, argv)
Xchar **argv;
X{
X int status;
X
X for (;;)
X#ifdef DEBUG
X sleep (2);
X#endif DEBUG
X switch (fork()) {
X default:
X return;
X case 0:
X if ((status = setgid(gid)) < 0)
X perror ("setting gid");
X if ((status = setuid(uid)) < 0)
X perror ("setting uid");
X/*
X execvp(*argv, argv);
X*/
X execv(*argv, argv);
X perror("master: exec'ing");
X printf("can't execute %s\n", *argv);
X/*
X kill(getppid(), SIGTERM);
X*/
X /* If the exec failed, don't try it again
X * immediately. Give the kernel
X * a chance to do something else
X */
X sleep (5);
X _exit(1);
X case -1:
X sleep(10);
X }
X}
X
Xmain(argc, argv)
Xchar **argv;
X{
X register n, uid, gid;
X
X /* Minix can't do this
X setpgrp(getpid(), getpid());
X */
X if (argc < 4) {
X prints("Usage: master # uid gid command args ...\n");
X return(1);
X }
X n = atoi(argv[1]);
X if (n < 1 || n > 20) {
X prints("Bad count.\n");
X return(1);
X }
X signal(SIGHUP, SIG_IGN);
X signal(SIGINT, SIG_IGN);
X signal(SIGQUIT, SIG_IGN);
X
X/* Put the program into the background. */
X switch (fork()) {
X case 0:
X break;
X case -1:
X perror(argv[0]);
X return 1;
X default:
X return 0;
X }
X uid = atoi(argv[2]);
X gid = atoi(argv[3]);
X
X/* Start n copies of the program. */
X do
X run(uid, gid, &argv[4]);
X while (--n);
X
X/* Replace each one that dies. */
X while (wait((int *) 0) > 0)
X run(uid, gid, &argv[4]);
X return(0);
X}
SHAR_EOF
if test 1454 -ne "`wc -c < 'master.c'`"
then
echo shar: error transmitting "'master.c'" '(should have been 1454 characters)'
fi
fi # end of overwriting check
echo shar: extracting "'master.c~'" '(1423 characters)'
if test -f 'master.c~'
then
echo shar: will not over-write existing file "'master.c~'"
else
sed 's/^X//' << \SHAR_EOF > 'master.c~'
X#include <signal.h>
X
Xchar console[] = "/dev/console";
X
Xrun(uid, gid, argv)
Xchar **argv;
X{
X int status;
X
X for (;;)
X#ifdef DEBUG
X sleep (2);
X#endif DEBUG
X switch (fork()) {
X default:
X return;
X case 0:
X if ((status = setgid(gid)) < 0)
X perror ("setting gid");
X if ((status = setuid(uid)) < 0)
X perror ("setting uid");
X/*
X execvp(*argv, argv);
X*/
X execv(*argv, argv);
X perror("master: exec'ing");
X printf("can't execute %s\n", *argv);
X/*
X kill(getppid(), SIGTERM);
X*/
X /* If the exec failed, don't try it again
X * immediately. Give the kernel
X * a chance to do something else
X */
X sleep (5);
X _exit(1);
X case -1:
X sleep(10);
X }
X}
X
Xmain(argc, argv)
Xchar **argv;
X{
X register n, uid, gid;
X
X /* Minix can't do this
X setpgrp(getpid(), getpid());
X */
X if (argc < 4) {
X prints("Usage: master # uid gid command args ...\n");
X return(1);
X }
X n = atoi(argv[1]);
X if (n < 1 || n > 20) {
X prints("Bad count.\n");
X return(1);
X }
X signal(SIGHUP, SIG_IGN);
X signal(SIGINT, SIG_IGN);
X signal(SIGQUIT, SIG_IGN);
X
X/* Put the program into the background. */
X switch (fork()) {
X case 0:
X break;
X case -1:
X perror(argv[0]);
X return 1;
X default:
X return 0;
X }
X uid = atoi(argv[2]);
X gid = atoi(argv[3]);
X
X/* Start n copies of the program. */
X do
X run(uid, gid, &argv[4]);
X while (--n);
X
X/* Replace each one that dies. */
X while (wait((int *) 0) > 0)
X run(uid, gid, &argv[4]);
X return(0);
X}
SHAR_EOF
if test 1423 -ne "`wc -c < 'master.c~'`"
then
echo shar: error transmitting "'master.c~'" '(should have been 1423 characters)'
fi
fi # end of overwriting check
# End of shell archive
exit 0
--
-----------------------------------------------------------------------------
sane mailers: jonathan@comp.vuw.ac.nz | Industrial democracy:
UUCP path: ...!uunet!vuwcomp!jonathan | One factory, one vote!