Usenet 1994 October/usenetsourcesnewsgroupsinfomagicoctober1994disk2.iso/unix/volume18/mush6.4/part03/execute.c

C/C++ Source or Header | 1989-03-12 | 5.7 KB | 199 lines

/* execute.c     (c) copyright    10/28/86 (Dan Heller) */

#include "mush.h"
#ifdef BSD
#include <sys/wait.h>
#else
#ifndef SYSV
#include <wait.h>
#endif /* SYSV */
#endif /* BSD */

#ifdef lint
#include <sys/resource.h>
#endif /* lint */

execute(argv)
char **argv;
{
#ifdef SYSV
    int status;
#else
    union wait status;
#endif /* SYSV */
#ifdef SIGCONT
    SIGRET (*oldstop)(), (*oldcont)();
#endif /* SIGCONT */
    int pid;
    SIGRET (*oldint)(), (*oldquit)();

#ifdef SUNTOOL
    if (istool) {
    print("Editing letter...");

    panel_set(abort_item, PANEL_SHOW_ITEM, FALSE, 0);
    panel_set(send_item,  PANEL_SHOW_ITEM, FALSE, 0);
    panel_set(edit_item,  PANEL_SHOW_ITEM, FALSE, 0);
    win_setrect(tty_sw->ts_windowfd, &msg_rect);
    msg_rect.r_height = 0;
    win_setrect(msg_sw->ts_windowfd, &msg_rect);
    if ((exec_pid = ttysw_fork(tty_sw->ts_data, argv,
        &tty_sw->ts_io.tio_inputmask,
        &tty_sw->ts_io.tio_outputmask,
        &tty_sw->ts_io.tio_exceptmask)) == -1)
        error("%s failed", *argv), sigchldcatcher();
    Debug("tty pid = %d\n", exec_pid);
    return;
    }
#endif /* SUNTOOL */
    oldint = signal(SIGINT, SIG_IGN);
    oldquit = signal(SIGQUIT, SIG_IGN);
#ifdef SIGCONT
    oldstop = signal(SIGTSTP, SIG_DFL);
    oldcont = signal(SIGCONT, SIG_DFL);
#endif /* SIGCONT */
    turnon(glob_flags, IGN_SIGS);

    echo_on();
    if ((exec_pid = vfork()) == 0) {
    (void) signal(SIGINT, SIG_DFL);
    (void) signal(SIGQUIT, SIG_DFL);
    (void) signal(SIGPIPE, SIG_DFL);
    (void) closefileds(3);    /* close all descriptors above 2 */
    execvp(*argv, argv);
    if (errno == ENOENT)
        print("%s: command not found.\n", *argv);
    else
        error(*argv);
    _exit(-1);
    }
    /* parent's got to do something; sigchldcatcher will do waiting
     * if other forks die (sendmail), then this wait will catch them,
     * This loop will really get -1, cuz sigchldcatcher will catch all else.
     */
    while ((pid = wait(&status)) != -1 && pid != exec_pid)
    Debug("The exec loop caught a signal? (pid = %d)\n", pid);
    /* reset our ttymodes */
    echo_off();
    (void) signal(SIGINT, oldint);
    (void) signal(SIGQUIT, oldquit);
#ifdef SIGCONT
    (void) signal(SIGTSTP, oldstop);
    (void) signal(SIGCONT, oldcont);
#endif /* SIGCONT */
    turnoff(glob_flags, IGN_SIGS);
}

SIGRET
sigchldcatcher()
{
#ifdef SUNTOOL
    struct rect rect;
    extern FILE *ed_fp;
#endif /* SUNTOOL */
#ifdef SYSV
    int status;
#else
    union wait status;
#endif /* SYSV */
    int       pid;

#ifdef BSD
    /* The following SHOULDN'T be necessary, but it is!!! ttysw_fork()
     * returns the pid of the thing that it executes, but that's not the
     * pid that dies!  There are many procs that might die from ttysw_fork
     * one of them is the process, another is the tty, etc... other
     * procs that might die are sendmail, fortune, etc... tool_sigchld()
     * handles these, but we can't let it have control unless we KNOW the
     * editor is done.
     * so if what we catch is not the exec_pid from ttysw_fork(), then
     * send ourselves a sigchld to go thru this routine again.  mush -d
     */
    while ((pid = wait3(&status, WNOHANG, (struct rusage *)0)) > 0) {
    Debug("%d died...\n", pid);
    if (pid == exec_pid)
        break;
    }
#else
#ifndef SYSV
    while ((pid = wait2(&status, WNOHANG)) > 0 && pid != exec_pid)
    Debug("%d died...\n", pid);
#else /* SYSV */
    while ((pid = wait((int *)0)) > 0 && pid != exec_pid)
    Debug("%d died...\n", pid);
#endif /* SYSV */
#endif /* BSD */
#ifndef SUNTOOL
    }
#else /* SUNTOOL */
    if (pid != exec_pid || exec_pid <= 0) /* if the editor didn't die, return */
    return;
    /* editor died -- reset exec_pid so no one thinks we're running */
    exec_pid = 0;
    /* only the tool needs to continue from here.  Reset the win */
    if (istool < 1)
    return;
    tool_sigchld(tool);
    print("Editor done.");
    win_getrect(tty_sw->ts_windowfd, &msg_rect);
    if (msg_rect.r_height < 2 * l_height(curfont)) {
    print_more(" (well, something just happened)");
    return;
    }
    {
    extern char *edfile;
    if (!(ed_fp = fopen(edfile, "r+")))
        error("can't reopen %s", edfile);
    (void) fseek(ed_fp, 0L, 2);
    }
    /* I'd like to be able to just pw_rop the tty window onto the window
     * we're going to use now, but I can't access the data structure!
     *
     * pw_rop(msg_win, 0, 0, msg_rect.r_width, msg_rect.r_height, PIX_SRC,
     *        ((struct ??? *)(tty_sw->ts_data))->pr_pixrect, 0, 0);
     * So, instead, just clear the window and write the last N lines from the
     * end of the file into the window.
     */
    rect.r_top = rect.r_left = rect.r_height = 0;
    rect.r_width = msg_rect.r_width;
    win_setrect(tty_sw->ts_windowfd, &rect);
    win_setrect(msg_sw->ts_windowfd, &msg_rect);
    do_clear();
    /* read the last 2K bytes in the file -- search backwards for enough
     * carriage returns that will fill the window with the end of the letter
     * written so far and display the text.
     */
    {
    register long where = ftell(ed_fp);
    register int cr = 0, lines = msg_rect.r_height * l_height(curfont) - 3;
    char buf[2*BUFSIZ], *p;
    where = max(0, where-2*BUFSIZ);
    (void) fseek(ed_fp, where, L_SET);
    p = buf + read(fileno(ed_fp), buf, 2*BUFSIZ);
    *p = 0;
    while (cr < lines && p > buf)
        if (*--p == '\n')
        cr++;
    if (p > buf)
        while (*p != '\n')
        p++;
    Addstr(p);
    }
    panel_set(comp_item, PANEL_SHOW_ITEM, FALSE, 0);
    panel_set(send_item, PANEL_SHOW_ITEM, TRUE, 0);
    panel_set(edit_item, PANEL_SHOW_ITEM, TRUE, 0);
    panel_set(abort_item, PANEL_SHOW_ITEM, TRUE, 0);
    wprint("(continue editing letter.)\n");
    type_cursor(PIX_SRC);
}

SIGRET
sigtermcatcher()
{
    ttysw_done(tty_sw->ts_data);
    if (ison(glob_flags, IS_GETTING))
    rm_edfile(-1);
    cleanup(SIGTERM);
}
#endif /* SUNTOOL */