PTY: let closed master cause EOF on slave

This puts PTY on par with e.g. rs232 as well as behavior documented
for other OSes.  It is not a fix for an issue in userland, though.

- add a (minimal) test case to test77;
- fix a few other minor issues in test77.

Change-Id: I89c000921ee69dd9f5713665349c1ab1ad1dc2cc

diff --git a/minix/drivers/tty/pty/pty.c b/minix/drivers/tty/pty/pty.c
index 6fc49bc30920f1471fffdb2bf1e52cc2d59d340d..031d6082dc42bd235fd2b1a010cea4f3d62a0eb3 100644 (file)
--- a/minix/drivers/tty/pty/pty.c
+++ b/minix/drivers/tty/pty/pty.c
@@ -126,6 +126,7 @@ static int pty_master_close(devminor_t minor)
        pp->state = 0;
   } else {
        pp->state |= PTY_CLOSED;
+       tp->tty_termios.c_ospeed = B0; /* cause EOF on slave side */
        sigchar(tp, SIGHUP, 1);
   }
 

diff --git a/minix/tests/test77.c b/minix/tests/test77.c
index 2b8c68d095e04828a16ca6594af99a2832114b2d..fe0afcbc08504694bab148d7ab43e049d0b357db 100644 (file)
--- a/minix/tests/test77.c
+++ b/minix/tests/test77.c
@@ -20,7 +20,7 @@ static int sighups;           /* number of SIGHUP signals received */
 /*
  * Signal handler for SIGHUP and SIGUSR1.
  */
-void
+static void
 signal_handler(int sig)
 {
        if (sig == SIGHUP)
@@ -311,9 +311,28 @@ test77c(void)
        if (write(slavefd, &c, sizeof(c)) >= 0) e(18);
        if (errno != EIO) e(19);
 
-       if (close(slavefd) < 0) e(20);
+       /* Reads from the slave should return EOF if the master is gone. */
+       if (read(slavefd, &c, sizeof(c)) != 0) e(20);
+
+       if (close(slavefd) < 0) e(21);
+
+       if (sigaction(SIGHUP, &oact, NULL) < 0) e(22);
+}
+
+/*
+ * Wait for a child process to terminate.  Return 0 if the child exited without
+ * errors, -1 otherwise.
+ */
+static int
+waitchild(void)
+{
+       int status;
+
+       if (wait(&status) <= 0) return -1;
+       if (!WIFEXITED(status)) return -1;
+       if (WEXITSTATUS(status) != 0) return -1;
 
-       if (sigaction(SIGHUP, &oact, NULL) < 0) e(21);
+       return 0;
 }
 
 /*
@@ -348,14 +367,14 @@ test77d(void)
                if (open("/dev/tty", O_RDWR) >= 0) e(4);
                if (errno != ENXIO) e(5);
 
-               exit(0);
+               exit(errct);
        case -1:
                e(6);
        default:
                break;
        }
 
-       if (wait(NULL) <= 0) e(7);
+       if (waitchild() < 0) e(7);
 
        if (close(masterfd) < 0) e(8);
 
@@ -373,14 +392,14 @@ test77d(void)
 
                if (open("/dev/tty", O_RDWR) < 0) e(12);
 
-               exit(0);
+               exit(errct);
        case -1:
                e(13);
        default:
                break;
        }
 
-       if (wait(NULL) <= 0) e(14);
+       if (waitchild() < 0) e(14);
 
        if (close(masterfd) < 0) e(15);
 }
@@ -441,7 +460,7 @@ test77e(void)
 
                if (sighups != 1) e(9);
 
-               exit(0);
+               exit(errct);
        case -1:
                e(10);
        default:
@@ -455,7 +474,7 @@ test77e(void)
        /* Closing the master should now raise a SIGHUP signal in the child. */
        if (close(masterfd) < 0) e(12);
 
-       if (wait(NULL) <= 0) e(13);
+       if (waitchild() < 0) e(13);
 
        if (sigprocmask(SIG_SETMASK, &oset, NULL) < 0) e(14);