1
0
mirror of https://github.com/cc65/cc65.git synced 2024-12-24 11:31:31 +00:00
cc65/libsrc/cbm/cbm_dir.c
uz 2f87dbc27e Allow a third, optional filename argument for cbm_opendir.
git-svn-id: svn://svn.cc65.org/cc65/trunk@5683 b7a2c559-68d2-44c3-8de9-860c34a00d81
2012-06-04 18:32:38 +00:00

188 lines
5.3 KiB
C

/* This is a very simplified version of the POSIX opendir(), */
/* readdir(), and closedir() -- for Commodore computers. */
/* Created by Josef Soucek, 2003. E-mail: josef.soucek@ct.cz */
/* 2003-01-21 -- Version 0.1 */
/* 2009-10-10 -- Version 0.3 */
/* 2011-04-07 -- Version 0.4, groepaz */
/* 2011-04-14 -- Version 0.5, Greg King */
/* Tested with floppy-drive and IDE64 devices. */
/* Not tested with messed (buggy) directory listings. */
/* Limits filenames to 16 chars. (VICE supports more */
/* in directory listings). */
#include <stdarg.h>
#include <cbm.h>
#include <errno.h>
/* Opens directory listing. Returns 0 if opening directory was successful;
** otherwise, an error-code corresponding to cbm_open(). As an optional
** argument, the name of the directory may be passed to the function. If
** no explicit name is specified, "$" is used.
*/
unsigned char cbm_opendir (unsigned char lfn, unsigned char device, ...)
{
va_list ap;
const char* name = "$";
/* The name used in cbm_open may optionally be passed */
if (__argsize__ == 4) {
va_start (ap, device);
name = va_arg (ap, const char*);
va_end (ap);
}
/* Open the directory */
if (cbm_open (lfn, device, CBM_READ, name) == 0) {
if ((_oserror = cbm_k_chkin (lfn)) == 0) {
/* Ignore start address */
cbm_k_basin();
cbm_k_basin();
cbm_k_clrch();
if (cbm_k_readst()) {
cbm_close(lfn);
_oserror = 4; /* directory cannot be read */
}
}
}
return _oserror;
}
/* Reads one directory line into cbm_dirent structure.
** Returns 0 if reading directory-line was successful.
** Returns non-zero if reading directory failed, or no more file-names to read.
** Returns 2 on last line. Then, l_dirent->size = the number of "blocks free."
*/
unsigned char __fastcall__ cbm_readdir (unsigned char lfn, register struct cbm_dirent* l_dirent)
{
unsigned char byte, i = 0;
unsigned char is_header = 0;
unsigned char rv = 1;
if (!cbm_k_chkin(lfn)) {
if (!cbm_k_readst()) {
/* skip 2 bytes, next-BASIC-line pointer */
cbm_k_basin();
cbm_k_basin();
/* File-size or drive/partition number */
l_dirent->size = cbm_k_basin() | (cbm_k_basin() << 8);
byte = cbm_k_basin();
switch (byte) {
/* "B" BLOCKS FREE. */
case 'b':
/* Read until end; careless callers might call us again. */
while (!cbm_k_readst()) {
cbm_k_basin();
}
rv = 2; /* EOF */
goto ret_val;
/* Reverse-text shows when this is the directory header. */
case 0x12: /* RVS_ON */
is_header = 1;
}
while (byte != '\"') {
/* prevent endless loop */
if (cbm_k_readst()) {
rv = 3;
goto ret_val;
}
byte = cbm_k_basin();
}
while ((byte = cbm_k_basin()) != '\"') {
/* prevent endless loop */
if (cbm_k_readst()) {
rv = 4;
goto ret_val;
}
if (i < sizeof (l_dirent->name) - 1) {
l_dirent->name[i] = byte;
++i;
}
}
l_dirent->name[i] = '\0';
if (is_header) {
l_dirent->type = CBM_T_HEADER;
/* Get the disk-format code. */
i = 6;
do {
l_dirent->access = byte = cbm_k_basin();
} while (--i != 0);
} else {
/* Go to the file-type column. */
while ((byte = cbm_k_basin()) == ' ') {
/* prevent endless loop */
if (cbm_k_readst()) {
rv = 5;
goto ret_val;
}
}
l_dirent->access = CBM_A_RW;
/* "Splat" files shouldn't be read. */
if (byte == '*') {
l_dirent->access = CBM_A_WO;
byte = cbm_k_basin();
}
/* Determine the file type */
l_dirent->type = _cbm_filetype (byte);
/* Notice whether it's a directory or a deleted file. */
if (cbm_k_basin() == 'i' && byte == 'd') {
l_dirent->type = CBM_T_DIR;
}
cbm_k_basin();
/* Locked files shouldn't be written. */
if ((byte = cbm_k_basin()) == '<') {
l_dirent->access = (l_dirent->access == CBM_A_WO)
? 0 : CBM_A_RO;
}
}
/* Read to the end of the line. */
while (byte != 0) {
/* prevent endless loop */
if (cbm_k_readst()) {
rv = 6;
goto ret_val;
}
byte = cbm_k_basin();
}
rv = 0;
goto ret_val;
}
}
ret_val:
cbm_k_clrch();
return rv;
}
void __fastcall__ cbm_closedir (unsigned char lfn)
{
cbm_close(lfn);
}