BSD 4_4 release

[unix-history] / usr / src / lib / libcurses / tstp.c

diff --git a/usr/src/lib/libcurses/tstp.c b/usr/src/lib/libcurses/tstp.c
index fb9f0d8..a7670d0 100644 (file)
--- a/usr/src/lib/libcurses/tstp.c
+++ b/usr/src/lib/libcurses/tstp.c
@@ -1,47 +1,123 @@
 /*
 /*

- * Copyright (c) 1981 Regents of the University of California.
- * All rights reserved.
+ * Copyright (c) 1981, 1993
+ *     The Regents of the University of California.  All rights reserved.

  *
  *

- * %sccs.include.redist.c%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *     This product includes software developed by the University of
+ *     California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.

  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static char sccsid[] = "@(#)tstp.c     5.7 (Berkeley) %G%";
+static char sccsid[] = "@(#)tstp.c     8.1 (Berkeley) 6/7/93";

 #endif /* not lint */
 
 #endif /* not lint */
 

-# include      <signal.h>
+#include <curses.h>
+#include <errno.h>
+#include <signal.h>
+#include <termios.h>
+#include <unistd.h>

 
 

-# include      "curses.ext"

 
 /*
 
 /*

- * handle stop and start signals
- *
- * @(#)tstp.c  5.7 (Berkeley) %G%
+ * stop_signal_handler --
+ *     Handle stop signals.

  */
 void
  */
 void

-tstp() {
-
-# ifdef SIGTSTP
-
-       SGTTY   tty;
-       int     omask;
-# ifdef DEBUG
-       if (outf)
-               fflush(outf);
-# endif
-       tty = _tty;
-       mvcur(0, COLS - 1, LINES - 1, 0);
+__stop_signal_handler(signo)
+       int signo;
+{
+       struct termios save;
+       sigset_t oset, set;
+
+       /* Get the current terminal state (which the user may have changed). */
+       if (tcgetattr(STDIN_FILENO, &save))
+               return;
+
+       /*
+        * Block every signal we can get our hands on.  This is because
+        * applications have timers going off that want to repaint the
+        * screen.
+        */
+       (void)sigfillset(&set);
+       (void)sigprocmask(SIG_BLOCK, &set, &oset);
+       
+       /*
+        * End the window, which also resets the terminal state to the
+        * original modes.
+        */

        endwin();
        endwin();

-       fflush(stdout);
-       /* reset signal handler so kill below stops us */
-       signal(SIGTSTP, SIG_DFL);
-#define        mask(s) (1 << ((s)-1))
-       omask = sigsetmask(sigblock(0) &~ mask(SIGTSTP));
-       kill(0, SIGTSTP);
-       sigblock(mask(SIGTSTP));
-       signal(SIGTSTP, tstp);
-       _tty = tty;
-       ioctl(_tty_ch, TIOCSETP, &_tty);
+
+       /* Unblock SIGTSTP. */
+       (void)sigemptyset(&set);
+       (void)sigaddset(&set, SIGTSTP);
+       (void)sigprocmask(SIG_UNBLOCK, &set, NULL);
+
+       /* Stop ourselves. */
+       __restore_stophandler();
+       (void)kill(0, SIGTSTP);
+
+       /* Time passes ... */
+
+       /* Reset the curses SIGTSTP signal handler. */
+       __set_stophandler();
+
+       /* save the new "default" terminal state */
+       (void)tcgetattr(STDIN_FILENO, &__orig_termios);
+
+       /* Reset the terminal state to the mode just before we stopped. */
+       (void)tcsetattr(STDIN_FILENO, __tcaction ?
+           TCSASOFT | TCSADRAIN : TCSADRAIN, &save);
+
+       /* Restart the screen. */
+       __startwin();
+
+       /* Repaint the screen. */

        wrefresh(curscr);
        wrefresh(curscr);

-# endif        SIGTSTP
+
+       /* Reset the signals. */
+       (void)sigprocmask(SIG_SETMASK, &oset, NULL);
+}
+
+static void (*otstpfn)() = SIG_DFL;
+
+/*
+ * Set the TSTP handler.
+ */
+void
+__set_stophandler()
+{
+       otstpfn = signal(SIGTSTP, __stop_signal_handler);
+}
+
+/*
+ * Restore the TSTP handler.
+ */
+void
+__restore_stophandler()
+{
+       (void)signal(SIGTSTP, otstpfn);

 }
 }