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/* ----------------------------------------------------------------------- *
*
* Copyright 2004-2008 H. Peter Anvin - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* searchdir.c
*
* Search a FAT directory for a particular pre-mangled filename.
* Copies the directory entry into direntry and returns the starting cluster
* if found; returns -2 on not found, -1 on error, 0 on empty file.
*/
#include <string.h>
#include "libfatint.h"
int32_t libfat_searchdir(struct libfat_filesystem *fs, int32_t dirclust,
const void *name, struct libfat_direntry *direntry)
{
struct fat_dirent *dep;
int nent;
libfat_sector_t s = libfat_clustertosector(fs, dirclust);
while (1) {
if (s == 0)
return -2; /* Not found */
else if (s == (libfat_sector_t) - 1)
return -1; /* Error */
dep = libfat_get_sector(fs, s);
if (!dep)
return -1; /* Read error */
for (nent = 0; nent < LIBFAT_SECTOR_SIZE;
nent += sizeof(struct fat_dirent)) {
if (!memcmp(dep->name, name, 11)) {
if (direntry) {
memcpy(direntry->entry, dep, sizeof(*dep));
direntry->sector = s;
direntry->offset = nent;
}
if (read32(&dep->size) == 0)
return 0; /* An empty file has no clusters */
else
return read16(&dep->clustlo) +
(read16(&dep->clusthi) << 16);
}
if (dep->name[0] == 0)
return -2; /* Hit high water mark */
dep++;
}
s = libfat_nextsector(fs, s);
}
}
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