git.sur5r.net Git - cc65/blob - libsrc/apple2/opendir.c

   1 /*****************************************************************************/
   2 /*                                                                           */
   3 /*                                opendir.h                                  */
   4 /*                                                                           */
   5 /*                             Open a directory                              */
   6 /*                                                                           */
   7 /*                                                                           */
   8 /*                                                                           */
   9 /* (C) 2005  Oliver Schmidt, <ol.sc@web.de>                                  */
  10 /*                                                                           */
  11 /*                                                                           */
  12 /* This software is provided 'as-is', without any expressed or implied       */
  13 /* warranty.  In no event will the authors be held liable for any damages    */
  14 /* arising from the use of this software.                                    */
  15 /*                                                                           */
  16 /* Permission is granted to anyone to use this software for any purpose,     */
  17 /* including commercial applications, and to alter it and redistribute it    */
  18 /* freely, subject to the following restrictions:                            */
  19 /*                                                                           */
  20 /* 1. The origin of this software must not be misrepresented; you must not   */
  21 /*    claim that you wrote the original software. If you use this software   */
  22 /*    in a product, an acknowledgment in the product documentation would be  */
  23 /*    appreciated but is not required.                                       */
  24 /* 2. Altered source versions must be plainly marked as such, and must not   */
  25 /*    be misrepresented as being the original software.                      */
  26 /* 3. This notice may not be removed or altered from any source              */
  27 /*    distribution.                                                          */
  28 /*                                                                           */
  29 /*****************************************************************************/
  30
  31
  32
  33 #include <stddef.h>
  34 #include <stdlib.h>
  35 #include <stdio.h>
  36 #include <unistd.h>
  37 #include <fcntl.h>
  38 #include <errno.h>
  39 #include <dirent.h>
  40 #include "dir.h"
  41
  42
  43
  44 /*****************************************************************************/
  45 /*                                   Data                                    */
  46 /*****************************************************************************/
  47
  48
  49
  50 extern char _cwd[FILENAME_MAX];
  51
  52
  53
  54 /*****************************************************************************/
  55 /*                                   Code                                    */
  56 /*****************************************************************************/
  57
  58
  59
  60 DIR* __fastcall__ opendir (register const char* name)
  61 {
  62     register DIR* dir;
  63
  64     /* Alloc DIR */
  65     if ((dir = malloc (sizeof (*dir))) == NULL) {
  66
  67         /* May not have been done by malloc() */
  68         _directerrno (ENOMEM);
  69
  70         /* Return failure */
  71         return NULL;
  72     }
  73
  74     /* Interpret dot as current working directory */
  75     if (*name == '.') {
  76         name = _cwd;
  77     }
  78
  79     /* Open directory file */
  80     if ((dir->fd = open (name, O_RDONLY)) != -1) {
  81
  82         /* Read directory key block */
  83         if (read (dir->fd,
  84                   dir->block.bytes,
  85                   sizeof (dir->block)) == sizeof (dir->block)) {
  86
  87             /* Get directory entry infos from directory header */
  88             dir->entry_length      = dir->block.bytes[0x23];
  89             dir->entries_per_block = dir->block.bytes[0x24];
  90
  91             /* Skip directory header entry */
  92             dir->current_entry = 1;
  93
  94             /* Return success */
  95             return dir;
  96         }
  97
  98         /* EOF: Most probably no directory file at all */
  99         if (_oserror == 0) {
 100             _directerrno (EINVAL);
 101         }
 102
 103         /* Cleanup directory file */
 104         close (dir->fd);
 105     }
 106
 107     /* Cleanup DIR */
 108     free (dir);
 109
 110     /* Return failure */
 111     return NULL;
 112 }