lnxinit.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 196 行

/****************************************************************************
*
*                            Open Watcom Project
*
*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
*  ========================================================================
*
*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
*    Public License version 1.0 (the 'License'). You may not use this file
*    except in compliance with the License. BY USING THIS FILE YOU AGREE TO
*    ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
*    provided with the Original Code and Modifications, and is also
*    available at www.sybase.com/developer/opensource.
*
*    The Original Code and all software distributed under the License are
*    distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
*    EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
*    ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
*    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
*    NON-INFRINGEMENT. Please see the License for the specific language
*    governing rights and limitations under the License.
*
*  ========================================================================
*
* Description:  Linux initialization support routines for wd
*
****************************************************************************/


#include "dbgdefn.h"
#include <string.h>
#include <stddef.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>

int                     _8087 = 0;
int                     _real87 = 0;


extern void     DebugMain( void );
extern void     DebugFini( void );
extern char     *StrCopy( char *, char * );

extern int      DbgConHandle; /* Debugger console file handle */
extern char     **_argv;
extern int      _argc;

#ifndef __WATCOMC__
extern char     **environ;
#endif

static char             *CmdStart;
static volatile bool    BrkPending;
static unsigned         NumArgs;

/* following are to stop the C library from hauling in stuff we don't want */
void (*__abort)();
void __sigabort() {}

static void BrkHandler( int signo )
{
    signo = signo;
    BrkPending = 1;
}

void GUImain( void )
{
    struct sigaction sa;

    CmdStart = _argv[1];
    NumArgs = _argc - 1;

    /*
       This is so that the debugger can be made set UID root to get ring 1 access
       for the parallel trap file, without being a security hole.
    */
    setegid( getgid() );
    seteuid( getuid() );
    sa.sa_flags = SA_RESTART;
    sa.sa_handler = BrkHandler;
    sigaction( SIGINT, &sa, NULL );
    DebugMain();
}


int GUISysInit( int param )
{
    param=param;
    return( 1 );
}

void GUISysFini( void  )
{
    DebugFini();
}

void WndCleanUp()
{
}

char *GetCmdArg( int num )
{
    char    *cmd;

    if( num >= NumArgs || CmdStart == NULL ) return( NULL );
    for( cmd = CmdStart; num != 0; --num ) {
        cmd += strlen( cmd ) + 1;
    }
    return( cmd );
}

void SetCmdArgStart( int num, char *ptr )
{
    NumArgs -= num;
    if( ptr != NULL && *ptr == NULLCHAR ) ++ptr;
    CmdStart = (char *)ptr;
}

void KillDebugger()
{
    exit( 0 );
}

void GrabHandlers()
{
}

void RestoreHandlers()
{
}

bool TBreak()
{
    bool    ret;

    ret = BrkPending;
    BrkPending = 0;
    return( ret );
}

long _fork( char *cmd, unsigned len )
{
    char    buff[256];
    const char    *argv[4];
    char    *shell;
    pid_t   pid;
    
    shell = getenv( "SHELL" );
    if( shell == NULL ) shell = "/bin/sh";

    argv[0] = shell;
    if( len != 0 ) {
        argv[1] = "-c";
        memcpy( buff, cmd, len );
        buff[len] = NULLCHAR;
        argv[2] = buff;
        argv[3] = NULL;
    } else {
        argv[1] = NULL;
    }
    fcntl( DbgConHandle, F_SETFD, 0 );
    if ((pid = fork()) == 0) {
            /* make sure STDIN/STDOUT/STDERR are connected to a terminal */
            dup2( DbgConHandle, 0 );
            dup2( DbgConHandle, 1 );
            dup2( DbgConHandle, 2 );
            close( DbgConHandle );
            setsid(); 
            execve(shell, argv, (const char **)environ);
            exit( 1 );
    } else {
            fcntl( DbgConHandle, F_SETFD, (int)FD_CLOEXEC );
            if( pid == -1 ) return( 0xffff0000 | errno );
            do {
            } while( waitpid( pid, NULL, 0 ) == -1 && errno == EINTR );
    }
    return 0;
}

void SysSetMemLimit()
{
}

bool SysGUI()
{
    return( FALSE );
}