root/lang/objective-cplusplus/i3/trunk/src/os-windows/fakecygpty.c @ 35128

/*
 * Fake cygwin pty   --  fakecygpty --
 *
 *        Copyright (C) 2005 Kyotaro Horiguchi <horiguti@meaodwy.org>
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either versions 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with fiber, see the file COPYING.  If not, write to the Free
 * Software Foundation Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*
 * HISTORY
 * -------
 *
 *    09 Jun, 2005 : Version 1.0.0 - first release.
 *    15 Jun, 2005 : Version 1.0.1 - bug fix and change coding style.
 */

/*
 * COMPILATION
 * -------
 * gcc -o fakecygpty.exe fakecygpty.c
 *
 */

#ifndef __CYGWIN__
/* Interix */
#define _ALL_SOURCE
#endif

#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <termios.h>
#include <unistd.h>

#define BUFSIZE          1024   /* size of communication buffer */

/* global variables */
int child_pid;          /* pid of child proces  */
int masterfd;           /* fd of pty served to child process */

/* Create pty and fork/exec target process */
/* This function sets child_pid and masterfd */
void exec_target(char* argv[]) {
    int fd;
    int pid;

    masterfd = open ("/dev/ptmx", O_RDWR);
    if (masterfd < 0) {
        perror("Cannot open pseudo tty");
        exit (1);
    }

    pid = fork ();
    if (pid < 0) {
        perror ("Failed to fork");
        return;
    }

    if (pid == 0) {
        int slave;

        setsid();

        slave = open (ptsname (masterfd), O_RDWR);
        if (slave < 0) {
            perror ("Failed to open slave fd");
            exit (1);
        }

        for (fd = 0 ; fd < 3 ; fd++) {
            if (slave != fd) {
                if (dup2 (slave, fd) < 0) {
                    perror ("Failed to dup2");
                    exit (1);
                }
            }
            fcntl (fd, F_SETFD, 0);
        }

        if (slave > 2) {
            close (slave);
        }

        execvp (argv[0], argv);

        fprintf (stderr, "Failed to execute \"%s\".", argv[0]);
        perror ("execvp");
        exit (1);
    }

    child_pid = pid;

    return;
}

struct termios oldtm;

void setup_tty_attributes (void) {
    struct termios tm;

    if (tcgetattr (masterfd, &tm) == 0) {
        /* Inhibit echo when executed under emacs/windows environment */
        if (! isatty (0)) {
            tm.c_iflag |= IGNCR;
            tm.c_lflag &= ~ECHO;
        }
        tcsetattr (masterfd, TCSANOW, &tm);
    }

    if (tcgetattr (0, &oldtm) == 0) {
        tm = oldtm;
        tm.c_iflag &= ~(ICRNL | IXON | IXOFF);
        tm.c_iflag |= IGNBRK;
        tm.c_lflag &= ~(ICANON | ECHO | ISIG | ECHOE);
        tcsetattr (0, TCSANOW, &tm);
    }
}

void restore_tty_attributes (void) {
    tcsetattr (0, TCSANOW, &oldtm);
}

#ifdef __CYGWIN__
/* Signal handler for convert SIGINT into ^C on pty */
/* This seems not able to be done within cygwin POSIX framework */
#include <windows.h>
BOOL WINAPI ctrl_handler(DWORD e) {
    switch (e) {
    case CTRL_C_EVENT:
        write (masterfd, "\003", 1);
        return TRUE;

    case CTRL_CLOSE_EVENT:
        kill (child_pid, SIGKILL);
        return FALSE;
    }
    return FALSE;
}
#endif

int main (int argc, char* argv[]) {
    fd_set sel, sel0;
    int status;

    if (argc < 2) {
        fprintf (stderr, "Unable to get argv[1].\n");
        exit (1);
    }

#ifdef __CYGWIN__
    /* SIGINT and SIGBREAK are indistinctive under cygwin environment. */
    /* Using Win32API to handle SIGINT.                              */
    SetConsoleCtrlHandler (ctrl_handler, TRUE);
#endif

    exec_target (argv + 1);

    setup_tty_attributes ();

    FD_ZERO (&sel0);
    FD_SET (masterfd, &sel0);
    FD_SET (0, &sel0);

    /* communication loop */
    while (1) {
        char buf[BUFSIZE];
        int ret;

        sel = sel0;
        if (select (FD_SETSIZE, &sel, NULL, NULL, NULL) <= 0) {
            break;
        }

        if (FD_ISSET (masterfd, &sel)) {
            ret = read (masterfd, buf, BUFSIZE);
            if (ret > 0) {
                write (1, buf, ret);
            } else {
                break;
            }
        } else if (FD_ISSET (0, &sel)) {
            ret = read (0, buf, BUFSIZE);
            if (ret > 0) {
                write (masterfd, buf, ret);
            } else {
                FD_CLR (0, &sel0);
                close (masterfd);
            }
        }
    }

    restore_tty_attributes ();

    kill (child_pid, SIGKILL);
    waitpid (child_pid, &status, 0);
    return status;
}