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#include "sysincludes.h"
#include "msdos.h"
#include "stream.h"
#include "mtools.h"
#include "file.h"
#include "vfat.h"
#include "fs.h"
/* #define DEBUG */
/*
* Read a directory entry into caller supplied buffer
*/
struct directory *dir_read(Stream_t *Dir,
struct directory *dir,
int num,
struct vfat_state *v)
{
if(force_read(Dir, (char *) dir, num * MDIR_SIZE, MDIR_SIZE) !=
MDIR_SIZE)
return NULL;
if (v && (dir->attr == 0x0f) && dir->name[0] != DELMARK) {
struct vfat_subentry *vse;
unsigned char id, last_flag;
char *c;
vse = (struct vfat_subentry *) dir;
id = vse->id & VSE_MASK;
last_flag = (vse->id & VSE_LAST);
if (id > MAX_VFAT_SUBENTRIES) {
fprintf(stderr, "dir_read: invalid VSE ID %d at %d.\n",
id, num);
return dir;
}
/* 950819: This code enforced finding the VSEs in order. Well, Win95
* likes to write them in *reverse* order for some bizarre reason! So
* we pretty much have to tolerate them coming in any possible order.
* So skip this check, we'll do without it (What does this do, Alain?).
*
* 950820: Totally rearranged code to tolerate any order but to warn if
* they are not in reverse order like Win95 uses.
*
* 950909: Tolerate any order. We recognize new chains by mismatching
* checksums. In the event that the checksums match, new entries silently
* overwrite old entries of the same id. This should accept all valid
* entries, but may fail to reject invalid entries in some rare cases.
*/
/* bad checksum, begin new chain */
if(v->sum != vse->sum) {
clear_vfat(v);
v->sum = vse->sum;
}
#ifdef DEBUG
if(v->status & (1 << (id-1)))
fprintf(stderr,
"dir_read: duplicate VSE %d\n", vse->id);
#endif
v->status |= 1 << (id-1);
if(last_flag)
v->subentries = id;
#ifdef DEBUG
if (id > v->subentries)
/* simple test to detect entries preceding
* the "last" entry (really the first) */
fprintf(stderr,
"dir_read: new VSE %d sans LAST flag\n",
vse->id);
#endif
c = &(v->name[VSE_NAMELEN * (id-1)]);
c += unicode_read(vse->text1, c, VSE1SIZE);
c += unicode_read(vse->text2, c, VSE2SIZE);
c += unicode_read(vse->text3, c, VSE3SIZE);
#ifdef DEBUG
printf("Read VSE %d at %d, subentries=%d, = (%13s).\n",
id,num,v->subentries,&(v->name[VSE_NAMELEN * (id-1)]));
#endif
if (last_flag)
*c = '\0'; /* Null terminate long name */
}
return dir;
}
/*
* Make a subdirectory grow in length. Only subdirectories (not root)
* may grow. Returns a 0 on success, 1 on failure (disk full), or -1
* on error.
*/
int dir_grow(Stream_t *Dir, int size)
{
Stream_t *Stream = GetFs(Dir);
DeclareThis(FsPublic_t);
int ret;
int buflen;
char *buffer;
buflen = This->cluster_size * This->sector_size;
if(! (buffer=malloc(buflen)) ){
perror("dir_grow: malloc");
return -1;
}
memset((char *) buffer, '\0', buflen);
ret = force_write(Dir, buffer, size * MDIR_SIZE, buflen);
if(ret < buflen)
return -1;
return 0;
}
void dir_write(Stream_t *Dir, int num, struct directory *dir)
{
force_write(Dir, (char *) dir, num * MDIR_SIZE, MDIR_SIZE);
}
/*
* Make a directory entry. Builds a directory entry based on the
* name, attribute, starting cluster number, and size. Returns a pointer
* to a static directory structure.
*/
struct directory *mk_entry(const char *filename, char attr,
unsigned int fat, size_t size, long date,
struct directory *ndir)
{
struct tm *now;
time_t date2 = date;
unsigned char hour, min_hi, min_low, sec;
unsigned char year, month_hi, month_low, day;
now = localtime(&date2);
strncpy(ndir->name, filename, 8);
strncpy(ndir->ext, filename + 8, 3);
ndir->attr = attr;
ndir->ctime_ms = 0;
hour = now->tm_hour << 3;
min_hi = now->tm_min >> 3;
min_low = now->tm_min << 5;
sec = now->tm_sec / 2;
ndir->ctime[1] = ndir->time[1] = hour + min_hi;
ndir->ctime[0] = ndir->time[0] = min_low + sec;
year = (now->tm_year - 80) << 1;
month_hi = (now->tm_mon + 1) >> 3;
month_low = (now->tm_mon + 1) << 5;
day = now->tm_mday;
ndir -> adate[1] = ndir->cdate[1] = ndir->date[1] = year + month_hi;
ndir -> adate[0] = ndir->cdate[0] = ndir->date[0] = month_low + day;
set_word(ndir->start, fat & 0xffff);
set_word(ndir->startHi, fat >> 16);
set_dword(ndir->size, size);
return ndir;
}
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