/*
* Initiate a compare operation on a disk.
*/
static enum dpio_status DPDiskIOCompare(UNIT *uptr)
{
struct dpio_unit *iou = (struct dpio_unit *)uptr->up7;
uint16 numcy = ((uptr->flags & UNIT_854) != 0) ? DP_854CY : DP_853CY;
uint32 lba = DPLBA(iou);
int i;
if (iou->cylinder >= numcy)
return DPIO_ADDRERR;
/*
* Report any error in the underlying container infrastructure as an
* address error.
*/
if (sim_fseeko(uptr->fileref, lba * DP_NUMBY, SEEK_SET) ||
(sim_fread(iou->buf, sizeof(uint16), DP_NUMWD, uptr->fileref) != DP_NUMWD))
return DPIO_ADDRERR;
for (i = 0; i < DP_NUMWD; i++) {
if (iou->buf[i] != LoadFromMem(iou->CWA))
return DPIO_MISMATCH;
iou->CWA++;
if (iou->CWA == iou->LWA) {
DPDiskIOIncSector(iou);
return DPIO_DONE;
}
}
DPDiskIOIncSector(iou);
return DPIO_MORE;
}
/*
* Initiate a write operation on a disk.
*/
static enum dpio_status DPDiskIOWrite(UNIT *uptr)
{
struct dpio_unit *iou = (struct dpio_unit *)uptr->up7;
uint16 numcy = ((uptr->flags & UNIT_854) != 0) ? DP_854CY : DP_853CY;
uint32 lba = DPLBA(iou);
t_bool fill = FALSE;
int i;
if (iou->cylinder >= numcy)
return DPIO_ADDRERR;
for (i = 0; i < DP_NUMWD; i++) {
if (!fill) {
iou->buf[i] = LoadFromMem(iou->CWA);
iou->CWA++;
if (iou->CWA == iou->LWA)
fill = TRUE;
} else iou->buf[i] = 0;
}
/*
* Report any error in the underlying container infrastructure as an
* address error.
*/
if (sim_fseeko(uptr->fileref, lba * DP_NUMBY, SEEK_SET) ||
(sim_fwrite(iou->buf, sizeof(uint16), DP_NUMWD, uptr->fileref) != DP_NUMWD))
return DPIO_ADDRERR;
DPDiskIOIncSector(iou);
return fill ? DPIO_DONE : DPIO_MORE;
}
t_offset sim_fsize_ex (FILE *fp)
{
t_offset pos, sz;
if (fp == NULL)
return 0;
pos = sim_ftell (fp);
sim_fseek (fp, 0, SEEK_END);
sz = sim_ftell (fp);
sim_fseeko (fp, pos, SEEK_SET);
return sz;
}
/* Utility function to set the image type for a unit to the correct value.
* Prints an error message in case a CPT image is presented and returns
* SCPE_OPENERR in this case. Otherwise the return value is SCPE_OK
*/
t_stat assignDiskType(UNIT *uptr) {
t_stat result = SCPE_OK;
char header[4];
t_offset pos = sim_ftell(uptr->fileref);
sim_fseek(uptr->fileref, (t_addr)0, SEEK_SET);
if (fgets(header, 4, uptr->fileref) == NULL)
uptr->u3 = IMAGE_TYPE_DSK;
else if (strncmp(header, "IMD", 3) == 0)
uptr->u3 = IMAGE_TYPE_IMD;
else if(strncmp(header, "CPT", 3) == 0) {
sim_printf("CPT images not yet supported.\n");
uptr->u3 = IMAGE_TYPE_CPT;
result = SCPE_OPENERR;
}
else
uptr->u3 = IMAGE_TYPE_DSK;
sim_fseeko(uptr->fileref, pos, SEEK_SET);
return result;
}
int sim_fseek (FILE *st, t_addr offset, int whence)
{
return sim_fseeko (st, (t_offset)offset, whence);
}
