git.sur5r.net Git - cc65/blob - libsrc/cbm/cbm_dir.c

   1 /* This is very simplified version of POSIX opendir(), readdir() and closedir() */
   2 /* for Commodore computers.                                                     */
   3 /* Created by Josef Soucek, 2003    E-mail:josef.soucek@ct.cz                   */
   4
   5 /* Version 0.1 - 21.1.2003 */
   6 /* Tested with floppy drive and IDE64 devices                                   */
   7 /* Not tested with messed (buggy) directory listing                             */
   8 /* Limits filenames to 16 chars (VICE supports more in directory listing)       */
   9
  10
  11
  12 #include <cbm.h>
  13
  14
  15
  16 unsigned char __fastcall__ cbm_opendir (unsigned char lfn, unsigned char device)
  17 {
  18     unsigned char status;
  19     if ((status = cbm_open (lfn, device, CBM_READ, "$")) == 0) {
  20         if (cbm_k_chkin (lfn) == 0) {
  21             if (cbm_k_basin () == 0x01) {         /* Start address */
  22                 if (cbm_k_basin () == 0x04) {
  23                     cbm_k_clrch ();
  24                     return 0;
  25                 }
  26             } else {
  27                 cbm_close (lfn);
  28                 cbm_k_clrch ();
  29                 return 2;
  30             }
  31         }
  32     }
  33     return status;
  34 }
  35
  36
  37
  38 unsigned char __fastcall__ cbm_readdir (unsigned char lfn, register struct cbm_dirent* l_dirent)
  39 {
  40     unsigned char byte, i;
  41     unsigned char rv;
  42     unsigned char is_header;
  43     static const unsigned char types[] = {
  44         CBM_T_OTHER, CBM_T_OTHER, CBM_T_CBM,   CBM_T_DIR,   /* a b c d */
  45         CBM_T_OTHER, CBM_T_OTHER, CBM_T_OTHER, CBM_T_OTHER, /* e f g h */
  46         CBM_T_OTHER, CBM_T_OTHER, CBM_T_OTHER, CBM_T_OTHER, /* i j k l */
  47         CBM_T_OTHER, CBM_T_OTHER, CBM_T_OTHER, CBM_T_PRG,   /* m n o p */
  48         CBM_T_OTHER, CBM_T_REL,   CBM_T_SEQ,   CBM_T_OTHER, /* q r s t */
  49         CBM_T_USR,   CBM_T_VRP                              /* u v     */
  50     };
  51
  52     rv = 1;
  53     is_header = 0;
  54
  55     if (!cbm_k_chkin(lfn)) {
  56         if (!cbm_k_readst()) {
  57             /* skip 2 bytes, next basic line pointer */
  58             cbm_k_basin();
  59             cbm_k_basin();
  60
  61             /* File-size */
  62             l_dirent->size = cbm_k_basin() | ((cbm_k_basin()) << 8);
  63
  64             byte = cbm_k_basin();
  65
  66             /* "B" BLOCKS FREE. */
  67             if (byte == 'b') {
  68                 /* Read until end, careless callers may call us again */
  69                 while (!cbm_k_readst()) {
  70                     cbm_k_basin();
  71                 }
  72                 rv = 2; /* EOF */
  73                 goto ret_val;
  74             }
  75
  76             /* reverse text shows that this is the directory header */
  77             if (byte == 0x12) { /* RVS_ON */
  78                 is_header = 1;
  79             }
  80
  81             while (byte != '\"') {
  82                 byte = cbm_k_basin();
  83                 /* prevent endless loop */
  84                 if (cbm_k_readst()) {
  85                     rv = 3;
  86                     goto ret_val;
  87                 }
  88             }
  89
  90             i = 0;
  91             while ((byte = cbm_k_basin()) != '\"') {
  92                 /* prevent endless loop */
  93                 if (cbm_k_readst()) {
  94                     rv = 4;
  95                     goto ret_val;
  96                 }
  97
  98                 if (i < sizeof (l_dirent->name) - 1) {
  99                     l_dirent->name[i] = byte;
 100                     ++i;
 101                 }
 102             }
 103             l_dirent->name[i] = '\0';
 104
 105             while ((byte = cbm_k_basin()) == ' ') {
 106                 /* prevent endless loop */
 107                 if (cbm_k_readst()) {
 108                     rv = 5;
 109                     goto ret_val;
 110                 }
 111             }
 112
 113             if (is_header) {
 114                 l_dirent->type = CBM_T_HEADER;
 115             } else {
 116                 if (byte >= 'a' && byte < 'a' + sizeof(types)) {
 117                     l_dirent->type = types[byte - 'a'];
 118                 } else {
 119                     l_dirent->type = CBM_T_OTHER;
 120                 }
 121
 122                 cbm_k_basin();
 123                 cbm_k_basin();
 124
 125                 byte = cbm_k_basin();
 126
 127                 l_dirent->access = (byte == 0x3C)? CBM_A_RO : CBM_A_RW;
 128             }
 129
 130             /* read to end of line */
 131             while (byte != 0) {
 132                 byte = cbm_k_basin();
 133                 /* prevent endless loop */
 134                 if (cbm_k_readst()) {
 135                     rv = 6;
 136                     goto ret_val;
 137                 }
 138             }
 139
 140             rv = 0;
 141             goto ret_val;
 142         }
 143     }
 144
 145 ret_val:
 146     cbm_k_clrch();
 147     return rv;
 148 }
 149
 150
 151 void __fastcall__ cbm_closedir( unsigned char lfn)
 152 {
 153     cbm_close(lfn);
 154 }
 155
 156