Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/103.lha/Spawn/x_main.c

C/C++ Source or Header | 1986-11-21 | 4.4 KB | 196 lines

/* x_main.c - self spawning startup code:
 *   from CLI - spawns a new process and returns to CLI
 *   from spawned process - runs normally except no stdio files opened
 *   from Workbench - runs normally
 */

/*    (notes from _main.c)
 *    This is common startup code for both the CLI and the WorkBench.
 *    When called from the WorkBench, argc is 0 and argv points to a
 *    WBStartup type of structure.
 */
/* _main.c is Copyright (C) 1986,1987 by Manx Software Systems, Inc. */


#include <fcntl.h>
#include <exec/alerts.h>
#include <exec/memory.h>
#include <libraries/dosextens.h>
#include <workbench/startup.h>
#include <functions.h>


/* some statics are given values (even if 0) to prevent them from being
   placed into udata and zeroed by crt0 */

extern long _savsp, _stkbase;

extern int errno;

extern int _argc, _arg_len;
extern char **_argv, *_arg_lin;
extern struct WBStartup *WBenchMsg;

extern struct _dev *_devtab;
extern short _numdev;

static long seg=0;
static char clistart;

_main(alen, aptr)
long alen;
char *aptr;
{
    register struct Process *pp, *_FindTask();
    void *_OpenLibrary(), *_GetMsg(), *_AllocMem();
    long _Input(), _Output(), _Open();
    static int t_argc=0, t_arg_len=0;
    static char **t_argv=0, *t_arg_lin=0;
    static BPTR t_cdir=0;

    if ((_devtab = _AllocMem(_numdev*(long)sizeof(struct _dev),
                                                    MEMF_CLEAR)) == 0) {
        Alert(AG_NoMemory, 0L);
#asm
        move.l    __savsp,sp        ;get back original stack pointer
        rts                        ;and exit
#endasm
    }

    _devtab[0].mode = O_RDONLY;
    _devtab[1].mode = _devtab[2].mode = O_WRONLY;

    _stkbase = _savsp - *((long *)_savsp+1) + 8;
    *(long *)_stkbase = 0x4d414e58L;

    pp = _FindTask(0L);
    if (pp->pr_CLI) {
        struct CommandLineInterface *cli = (struct CommandLineInterface *) ((long)pp->pr_CLI << 2);
        long *bcpl;
        void *tmpdosbase;

        seg = cli->cli_Module;

        if ((tmpdosbase = OpenLibrary("dos.library", 33L)) == 0) {      /* v1.1 compatibility */
            bcpl = (long *)*((long *)*((long *)*((long *)*((long *) _savsp+2)+1)-3)-3)+107;
            if (seg != *bcpl) _exit (1);
        }
        else {
            CloseLibrary(tmpdosbase);
            bcpl = 0;
        }

        /*      bcpl = (long *)*((long *)*((long *)*((long *)*((long *)pp->pr_ReturnAddr+1)+1)-3)-3)+106;   old stuff */

        _cli_parse(pp, alen, aptr);
        _devtab[0].mode |= O_STDIO;        /* shouldn't close if CLI */
        _devtab[1].mode |= O_STDIO;

        t_arg_lin = _arg_lin;
        t_arg_len = _arg_len;
        t_argv = _argv;
        t_argc = _argc;
        if (pp->pr_CurrentDir) t_cdir = DupLock (pp->pr_CurrentDir);
        clistart = 1;

        _Forbid();        /* prevent starting new task until this one goes away (uses common data) */
        if (CreateProc (_argv[0], 0L, seg, cli->cli_DefaultStack * 4)) {
            _arg_lin = 0;        /* prevent freeing these */
            if (bcpl) *bcpl = 0;
            cli->cli_Module = 0;
        }

        _exit(0);
    }

    if (t_argc) {
        _arg_lin = t_arg_lin;
        _arg_len = t_arg_len;
        _argc = t_argc;
        _argv = t_argv;
        _CurrentDir (t_cdir);
    }
    else {
        _WaitPort(&pp->pr_MsgPort);
        WBenchMsg = _GetMsg(&pp->pr_MsgPort);
        if (WBenchMsg->sm_ArgList)
            _CurrentDir(WBenchMsg->sm_ArgList->wa_Lock);
        _wb_parse(pp, WBenchMsg);
        _argv = (char **)WBenchMsg;
    }
    _devtab[0].fd = _Input();
    if (_devtab[1].fd = _Output())
        _devtab[2].fd = _Open("*", MODE_OLDFILE);
    main(_argc, _argv);
    exit(0);
}


extern void *MathBase, *MathTransBase, *MathIeeeDoubBasBase;
void (*_cln)();

_exit(code)
{
    long ret = code;
    register int fd;

    if (_devtab) {
        for (fd = 0 ; fd < _numdev ; fd++)
            close(fd);
        _FreeMem(_devtab, _numdev*(long)sizeof(struct _dev));
    }
    if (_cln)
        (*_cln)();
    if (MathTransBase)
        _CloseLibrary(MathTransBase);
    if (MathBase)
        _CloseLibrary(MathBase);
    if (MathIeeeDoubBasBase)
        _CloseLibrary(MathIeeeDoubBasBase);
    {
#asm
    mc68881
    move.l    4,a6                ;get ExecBase
    btst.b    #4,$129(a6)            ;check for 68881 flag in AttnFlags
    beq        1$                    ;skip if not
    move.l    a5,-(sp)
    lea        2$,a5
    jsr        -30(a6)             ;do it in supervisor mode
    move.l    (sp)+,a5
    bra        1$
2$
    clr.l    -(sp)
    frestore (sp)+                ;reset the ffp stuff
    rte                            ;and return
1$
#endasm
    }
    if (WBenchMsg == 0) {
        if (_arg_lin) {
            _FreeMem(_arg_lin, (long)_arg_len);
            _FreeMem(_argv, (long)(_argc+1)*sizeof(*_argv));
        }
        if (!clistart) {
            BPTR oldcdir = CurrentDir(NULL);

            if (oldcdir) UnLock(oldcdir);

            _Forbid();

            if (seg) UnLoadSeg (seg);
        }
    }
    else {
        _Forbid();
        _ReplyMsg(WBenchMsg);
    }
    {
#asm
        move.l    -4(a5),d0        ;pick up return exit code
        move.l    __savsp#,sp        ;get back original stack pointer
        rts                        ;and exit
#endasm
    }
}