sys/arch/i386/stand/lib/dosfile.c

   1 /*      $NetBSD: dosfile.c,v 1.16 2013/10/20 21:06:37 christos Exp $     */
   2
   3 /*
   4  * Copyright (c) 1996
   5  *      Matthias Drochner.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  *
  27  */
  28
  29 /*
  30  * DOS filesystem for libsa
  31  * standalone - uses no device, works only with DOS running
  32  * needs lowlevel parts from dos_file.S
  33  */
  34
  35 #include <lib/libsa/stand.h>
  36
  37 #include "diskbuf.h"
  38 #include "dosfile.h"
  39
  40 extern int dosopen(const char *);
  41 extern void dosclose(int);
  42 extern int dosread(int, char *, int);
  43 extern int dosseek(int, int, int);
  44
  45 struct dosfile {
  46         int doshandle, off;
  47 };
  48
  49 extern int doserrno;    /* in dos_file.S */
  50
  51 static int dos2errno(void);
  52
  53 static int
  54 dos2errno(void)
  55 {
  56         int err;
  57
  58         switch (doserrno) {
  59             case 1:
  60             case 4:
  61             case 12:
  62             default:
  63                 err = EIO;
  64             case 2:
  65             case 3:
  66                 err = ENOENT;
  67             case 5:
  68                 err = EPERM;
  69             case 6:
  70                 err = EINVAL;
  71         }
  72         return err;
  73 }
  74
  75 __compactcall int
  76 dos_open(const char *path, struct open_file *f)
  77 {
  78         struct dosfile *df;
  79
  80         df = (struct dosfile *) alloc(sizeof(*df));
  81         if (!df)
  82                 return -1;
  83
  84         df->off = 0;
  85         df->doshandle = dosopen(path);
  86         if (df->doshandle < 0) {
  87 #ifdef DEBUG
  88                 printf("DOS error %d\n", doserrno);
  89 #endif
  90                 dealloc(df, sizeof(*df));
  91                 return dos2errno();
  92         }
  93         f->f_fsdata = (void *) df;
  94         return 0;
  95 }
  96
  97 __compactcall int
  98 dos_read(struct open_file *f, void *addr, size_t size, size_t *resid)
  99 {
 100         struct dosfile *df;
 101         int             got;
 102         static int      tc = 0;
 103
 104         df = (struct dosfile *) f->f_fsdata;
 105
 106         if (!(tc++ % 4))
 107                 twiddle();
 108
 109         if ((unsigned long) addr >= 0x10000) {
 110                 u_int           lsize = size;
 111
 112                 while (lsize > 0) {
 113                         u_int           tsize;
 114                         size_t          tgot;
 115                         char            *p = addr;
 116
 117                         tsize = lsize;
 118
 119                         if (tsize > DISKBUFSIZE)
 120                                 tsize = DISKBUFSIZE;
 121
 122                         alloc_diskbuf(dos_read);
 123
 124                         tgot = dosread(df->doshandle, diskbufp, tsize);
 125                         if (tgot < 0) {
 126 #ifdef DEBUG
 127                                 printf("DOS error %d\n", doserrno);
 128 #endif
 129                                 return dos2errno();
 130                         }
 131                         memcpy(p, diskbufp, tgot);
 132
 133                         p += tgot;
 134                         lsize -= tgot;
 135
 136                         if (tgot != tsize)
 137                                 break;  /* EOF */
 138                 }
 139                 got = size - lsize;
 140         } else {
 141                 got = dosread(df->doshandle, addr, size);
 142
 143                 if (got < 0) {
 144 #ifdef DEBUG
 145                         printf("DOS error %d\n", doserrno);
 146 #endif
 147                         return dos2errno();
 148                 }
 149         }
 150
 151         df->off += got;
 152         size -= got;
 153
 154         if (resid)
 155                 *resid = size;
 156         return 0;
 157 }
 158
 159 __compactcall int
 160 dos_close(struct open_file *f)
 161 {
 162         struct dosfile *df;
 163         df = (struct dosfile *) f->f_fsdata;
 164
 165         dosclose(df->doshandle);
 166
 167         if (df)
 168                 dealloc(df, sizeof(*df));
 169         return 0;
 170 }
 171
 172 __compactcall int
 173 dos_write(struct open_file *f, void *start, size_t size, size_t *resid)
 174 {
 175         return EROFS;
 176 }
 177
 178 __compactcall int
 179 dos_stat(struct open_file *f, struct stat *sb)
 180 {
 181         sb->st_mode = 0444;
 182         sb->st_nlink = 1;
 183         sb->st_uid = 0;
 184         sb->st_gid = 0;
 185         sb->st_size = -1;
 186         return 0;
 187 }
 188
 189 __compactcall off_t
 190 dos_seek(struct open_file *f, off_t offset, int where)
 191 {
 192         struct dosfile *df;
 193         int             doswhence, res;
 194 #ifdef DOS_CHECK
 195         int             checkoffs;
 196 #endif
 197         df = (struct dosfile *) f->f_fsdata;
 198
 199         switch (where) {
 200         case SEEK_SET:
 201                 doswhence = 0;
 202 #ifdef DOS_CHECK
 203                 checkoffs = offset;     /* don't trust DOS */
 204 #endif
 205                 break;
 206         case SEEK_CUR:
 207                 doswhence = 1;
 208 #ifdef DOS_CHECK
 209                 checkoffs = df->off + offset;
 210 #endif
 211                 break;
 212         case SEEK_END:
 213                 doswhence = 2;
 214 #ifdef DOS_CHECK
 215                 checkoffs = -1; /* we dont know len */
 216 #endif
 217                 break;
 218         default:
 219                 errno = EOFFSET;
 220                 return -1;
 221         }
 222         res = dosseek(df->doshandle, offset, doswhence);
 223         if (res == -1) {
 224                 errno = dos2errno();
 225                 return -1;
 226         }
 227 #ifdef DOS_CHECK
 228         if ((checkoffs != -1) && (res != checkoffs)) {
 229                 printf("dosfile: unexpected seek result (%d+%d(%d)=%d)\n",
 230                        df->off, offset, where, res);
 231                 errno = EOFFSET;
 232                 return -1;
 233         }
 234 #endif
 235         df->off = res;
 236         return res;
 237 }