usr.bin/vi/interrupt.h

/*-
 * Copyright (c) 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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.
 *
 *      @(#)interrupt.h 8.1 (Berkeley) 1/9/94
 */

/*
 * Macros to declare the variables and then turn on and off interrupts.
 */
#define DECLARE_INTERRUPTS                                              \
        struct sigaction __act, __oact;                                 \
        struct termios __nterm, __term;                                 \
        u_int __istate;                                                 \
        int __isig, __termreset

/*
 * Search, global, and substitute interruptions.
 *
 * ISIG turns on VINTR, VQUIT and VSUSP.  We want VINTR to interrupt the
 * search, so we install a handler.  VQUIT is ignored by main() because
 * nvi never wants to catch it.  A handler for VSUSP should have been
 * installed by the screen code.
 */
#define SET_UP_INTERRUPTS(handler) {                                    \
        if (F_ISSET(sp->gp, G_ISFROMTTY)) {                             \
                __act.sa_handler = handler;                             \
                sigemptyset(&__act.sa_mask);                            \
                __act.sa_flags = 0;                                     \
                if (__isig = !sigaction(SIGINT, &__act, &__oact)) {     \
                        __termreset = 0;                                \
                        __istate = F_ISSET(sp, S_INTERRUPTIBLE);        \
                        F_CLR(sp, S_INTERRUPTED);                       \
                        F_SET(sp, S_INTERRUPTIBLE);                     \
                        if (tcgetattr(STDIN_FILENO, &__term)) {         \
                                rval = 1;                               \
                                msgq(sp, M_SYSERR, "tcgetattr");        \
                                goto interrupt_err;                     \
                        }                                               \
                        __nterm = __term;                               \
                        __nterm.c_lflag |= ISIG;                        \
                        if (tcsetattr(STDIN_FILENO,                     \
                            TCSANOW | TCSASOFT, &__nterm)) {            \
                                rval = 1;                               \
                                msgq(sp, M_SYSERR, "tcsetattr");        \
                                goto interrupt_err;                     \
                        }                                               \
                        __termreset = 1;                                \
                }                                                       \
        }                                                               \
}

#define TEAR_DOWN_INTERRUPTS {                                          \
        if (F_ISSET(sp->gp, G_ISFROMTTY) && __isig) {                   \
                if (sigaction(SIGINT, &__oact, NULL)) {                 \
                        rval = 1;                                       \
                        msgq(sp, M_SYSERR, "signal");                   \
                }                                                       \
                if (__termreset && tcsetattr(STDIN_FILENO,              \
                    TCSANOW | TCSASOFT, &__term)) {                     \
                        rval = 1;                                       \
                        msgq(sp, M_SYSERR, "tcsetattr");                \
                }                                                       \
                F_CLR(sp, S_INTERRUPTED);                               \
                if (!__istate)                                          \
                        F_CLR(sp, S_INTERRUPTIBLE);                     \
        }                                                               \
}