/* Copyright (C) 1981,1982 by Manx Software Systems.
   Copyright (C) 1982  Thomas Fenwick.
   Copyright (c) 1985 Allen Holub.

   Manx Software Systems is in no way responsible for this program.
   These portions may be reproduced for personal, non-profit use,
   only.  All other use is prohibited.  You should replace the croot in
   libc.lib with this module.  This posting includes a couple of
   minor hacks by wse */

#include "fcntl.h"
#include "errno.h"
#include "io.h"

#define MAXARGS 128
#define MAXBUF 128
#define LOADERSIZE 49
#define DEF_FCB 0x5c
#define FCBSIZE 36
#define NULL 0
#define QUOTE 0x22
#define CBUF    ((char *)0x80)
#define CBUFEND (char *)(0x80+128-LOADERSIZE)

#define srchfirst(fcb) (bdos (0x11, (fcb)) & 0xff)
#define srchnext(fcb) (bdos (0x12, (fcb)) & 0xff)
#define bdosopen(fcb)  (bdos (0x0f, (fcb)) & 0xff)
#define isalnum(c) (c >= 0x20 && c <= 0x7e)
int badfd(), noper();

/*
 * channel table: relates fd's to devices
 */
struct channel  chantab[] = {
         {
                2, 0, 1, 0, noper, 2    }
        ,
        {
                0, 2, 1, 0, noper, 2    }
        ,
        {
                0, 2, 1, 0, noper, 2    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
        {
                0, 0, 0, 0, badfd, 0    }
        ,
};

static char *Argv[MAXARGS];
static char Argbuf[MAXBUF];
static int Argc;

static int Doingpipe = 0;
static char *Cmdtail;

char *Pipe_in = "$PIPE.IN\0\0\0\0";
char *Pipe_out = "$PIPE.OUT\0\0\0";

Croot()
{
        register char *cp, *fname;
        register int k;

        clear (Argbuf, MAXBUF, (char) 32);
        blockmv(Argbuf, (char *)0x81, 127);
        clear (CBUF, MAXBUF, (char) 32);
        Argbuf[*CBUF & 0x7f] = 0;
        Argv[0] = "";
        cp = Argbuf;
        Argc = 1;
        while (Argc < MAXARGS)
        {
                while (*cp == ' ' || *cp == '\t')
                        ++cp;
                if (*cp == 0)
                {
                        break;
                }
                else if (*cp == '|')
                {
                        Doingpipe = 1;
                        Cmdtail = ++cp;
                        fname = Pipe_out;
                        k = 1;
                        goto redir2;
                }
                else if (*cp == '>')
                {               /* redirect output */
                        k = 1;
                        goto redirect;
                }
                else if (*cp == '<')
                {  /* redirect input */
                        k = 0;
redirect:
                        while (*++cp == ' ' || *cp == '\t')
                                ;
                        fname = cp;
                        while (*++cp)
                        {
                                if (*cp == ' ' || *cp == '\t')
                                {
                                        *cp++ = 0;
                                        break;
                                }
                        }
redir2:

                        close(k);
                        if (k)
                                k = creat(fname, 0666);
                        else
                                k = open(fname, O_RDONLY);
                        if (k == -1)
                        {
                                strcpy
                                (0x80, "Can't open file for redirection: ");
                                strcat(0x80, fname);
                                strcat(0x80, "\n");
                                write(2, 0x80, strlen(0x80));
                                exit(10);
                        }
                        if (Doingpipe)
                                break;
                }
                else if (*cp == QUOTE)
                {
                        Argv[Argc++] == ++cp;
                        while (*cp && (*cp != '"'))
                        {
                                cp++;
                        }
                        *cp++ = 0;
                }
                else if (haswild (cp))
                {
                        Argc += do_wild (cp, Argv + Argc, MAXARGS - Argc - 1);
                                goto skippast;
                        }
                                else
                                {
                                        Argv[Argc++] = cp;
skippast:
                                        while (*++cp)
                                        {
                                                if (*cp == ' ' || *cp == '\t')
                                                {
                                                        *cp++ = 0;
                                                        break;
                                                }
                                        }
                                }
                }
                exit(main(Argc,Argv));
        }

        exit(code)
        {
                register char *tailp, *src, *dest;
                static char buff[MAXARGS];

                clear (buff, MAXARGS, NULL);
                closall_();
                unlink (Pipe_in);
                if ( code )
                        unlink("A:$$$.SUB");
#ifdef DEBUG
                perr ("\r\nFirst Cmdtail = ");
                perr (Cmdtail);
                perr ("\r\n");
#endif
                if (Doingpipe)
                {
                        rename (Pipe_out, Pipe_in);
                        while (*Cmdtail == ' ')
                                Cmdtail++;
                        tailp = Cmdtail;
                        while (*tailp && *tailp != ' ')
                                tailp++;
                        if (*tailp)
                                *tailp++ = '\0';
                        sprintf (buff, "%s < %s", tailp, Pipe_in);
#ifdef DEBUG
                        perr ("\r\nnext Cmdtail = ");
                        perr (Cmdtail);
                        perr ("\r\n");
                        perr ("\r\nbuff = ");
                        perr (buff);
                        perr ("\r\n");
#endif
                        execl (Cmdtail, buff);
                        perr ("Couldn't open file at end of pipe: ");
                        perr (Cmdtail);
                        perr (".COM");
                        unlink ("A:$$$.SUB");
                        unlink ("$$$.SUB");
                }
                boot_();
        }

        execl (name, args)

        char *name, *args;

        {
                register char *cp, *dest, **argp;

                sprintf (CBUF, "%s.%s", name, "COM");
                initfcb ((char *) CBUF, (char *) DEF_FCB);
#ifdef DEBUG
                perr ("\r\nargs: ");
                perr (args);
                perr ("\r\n");
#endif
                if (bdosopen (DEF_FCB) == 0xff)
                        return (0);
                dest = CBUF + 1;
                for (argp = &args; *argp && dest < CBUFEND; argp++)
                {
                        for (cp = *argp;
                            *cp && dest < CBUFEND;
                            *dest++ = *cp++);
                        *dest++ = ' ';
                }
                *dest = '\0';
                *CBUF = (int) dest - (int) CBUF;
#ifdef DEBUG
                perr ("\r\nCBUF: ");
                perr (CBUF);
                perr ("\r\n");
#endif
                loadldr();

        }


        perr (str)

        char *str;

        {
                while (*str)
                        bdos (2, *str++);
        }

        badfd()
        {
                errno = EBADF;
                return -1;
        }

        noper()
        {
                return 0;
        }


        initfcb (filename, fcb)

        char *filename, *fcb;

        {
                register char *fp;
                register int i;

                for (i = FCBSIZE, fp = fcb; --i > 0; *fp++ = 0)
                        ;
                if (*filename && filename[1] == ':')
                {
                        *fcb = (char) (toupper (*filename) - 'A' + 1);
                        filename += 2;
                }
                expand_name (fcb, filename);
        }

        expand_name (dest, src)

        char *dest, *src;

        {
                register char *dot, *end, i;

                dot = ++dest;
                for (i = 11; --i >= 0;)
                        *dot++ = *(src) ? ' ' : '?';
                dot = &dest[8];
                end = &dest[10];
                while (*src && *src != ' ')
                {
                        if (*src == '*')
                        {
                                if (dest < dot)
                                {
                                        while (dest < dot)
                                                *dest++ = '?';
                                }
                                else
                                {
                                        while (dest <= end)
                                                *dest++ = '?';
                                }
                        }
                        else if (*src == '.')
                                dest = dot;
                        else
                                *dest++ = *src;
                        src++;
                }
        }

        int do_wild (fname, argv, maxarg)

                char *fname, **argv;
                int maxarg;

        {
                register char *dest, *src;
                register unsigned int tmp;
                register int i, argc = 0;
                extern char *alloc();

                initfcb ((char *) fname, (char *) DEF_FCB);
                if ((tmp = srchfirst (DEF_FCB)) != 0xff)
                {
                        do
                        {
                                if ((dest = fname = alloc (13)) == 0)
                                {
                                        perr ("Not enough memory to expand wildcard");
                                        exit (1);
                                }
                                src = ((char *) ((tmp << 5) + 0x80)) + 1;
                                if (*(fname + 1) == ':')
                                {
                                        *dest++ = *fname;
                                        *dest++ = ':';
                                }
                                for (i = 1; i <= 11; i++)
                                {
                                        if ((*src & 0x7f) != ' ')
                                                *dest++ = *src++;
                                        else
                                                src++;
                                        if (i == 8)
                                        {
                                                if ((*src & 0x7f) == ' ')
                                                        break;
                                                else
                                                        *dest++ = '.';
                                        }
                                }
                                *dest = '\0';
                                argv[argc++] = fname;
                                tmp = srchnext (DEF_FCB);
                        }
                                while ((tmp != 0xff) && (argc < maxarg));
                }
                return (argc);
        }

                haswild (str)

                char *str;

        {
                register int c;

                do
                {
                        c = *str++;
                        if (c == '*' || c == '?')
                                return (1);
                }
                        while (c && c != ' ');
                return (0);
        }