Windows NT 4.0 source code leak
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4.9 KiB

/*****************************************************************************
*
* COPYRIGHT 1993 - COLORADO MEMORY SYSTEMS, INC.
* ALL RIGHTS RESERVED.
*
******************************************************************************
*
* FILE: \SE\DRIVER\DEVICE\JUMBO\SRC\0X11002.C
*
* FUNCTION: cqd_CalcPosition
*
* PURPOSE: Calculate the desired tape position from the Logical
* Sector Number in the I/O Request.
*
* HISTORY:
* $Log: J:\se.vcs\driver\q117cd\src\0x11002.c $
*
* Rev 1.7 21 Jan 1994 18:21:24 KEVINKES
* Fixed compiler warnings.
*
* Rev 1.6 18 Jan 1994 16:21:14 KEVINKES
* Updated debug code.
*
* Rev 1.5 13 Jan 1994 13:51:48 KEVINKES
* Added divide by zero checking.
*
* Rev 1.4 30 Nov 1993 14:57:12 KEVINKES
* Removed the while loops from the calculations.
*
* Rev 1.3 23 Nov 1993 18:45:12 KEVINKES
* Modified CHECKED_DUMP calls for debugging over the serial port.
*
* Rev 1.2 22 Nov 1993 15:49:48 KEVINKES
* Changed CheckedDump to KDI_CHECKED_DUMP.
*
* Rev 1.1 08 Nov 1993 13:58:38 KEVINKES
* Removed bit-field structures, changed enumerated types to defines,
* changed all defines to uppercase, and changed kdi_wt2ticks to
* kdi_wt_004ms.
*
* Rev 1.0 18 Oct 1993 17:21:04 KEVINKES
* Initial Revision.
*
*****************************************************************************/
#define FCT_ID 0x11002
#include "include\public\adi_api.h"
#include "include\public\frb_api.h"
#include "include\private\kdi_pub.h"
#include "include\private\cqd_pub.h"
#include "q117cd\include\cqd_defs.h"
#include "q117cd\include\cqd_strc.h"
#include "q117cd\include\cqd_hdr.h"
/*endinclude*/
dStatus cqd_CalcPosition
(
/* INPUT PARAMETERS: */
CqdContextPtr cqd_context,
dUDWord block,
dUDWord number
/* UPDATE PARAMETERS: */
/* OUTPUT PARAMETERS: */
)
/* COMMENTS: *****************************************************************
*
* DEFINITIONS: *************************************************************/
{
/* DATA: ********************************************************************/
dStatus status=DONT_PANIC; /* dStatus or error condition.*/
dUDWord log_sect;
/* CODE: ********************************************************************/
/* First check if the desired sector is a legal one, i.e. is less */
/* than the maximum number of sectors on the tape. */
kdi_CheckedDump(
QIC117STOP,
"q117i: requested block %08x\n",
block );
if (block >= cqd_context->floppy_tape_parms.log_sectors) {
return kdi_Error(ERR_BAD_REQUEST, FCT_ID, ERR_SEQ_1);
}
/* Now we need to determine the sector ID information so that we */
/* can properly program the FDC. The ID information required is the */
/* head, cylinder, and sector numbers. The head number is calculated */
/* as log_sect / (floppy sectors per floppy side). This calculation */
/* is done in the while loop which also determines the logical floppy */
/* sector on the floppy side. The cylinder number (d_FTK) and the */
/* sector number (d_sect) are calculated last as (logical floppy sector) */
/* / (floppy sectors per floppy cylinder). */
log_sect = block;
cqd_context->rd_wr_op.d_head = 0;
if (cqd_context->floppy_tape_parms.fsect_fside != 0) {
cqd_context->rd_wr_op.d_head =
(dUByte)(log_sect / cqd_context->floppy_tape_parms.fsect_fside);
log_sect = log_sect % cqd_context->floppy_tape_parms.fsect_fside;
} else {
return kdi_Error(ERR_UNKNOWN_TAPE_LENGTH, FCT_ID, ERR_SEQ_1);
}
cqd_context->rd_wr_op.d_ftk = (dUByte)(log_sect / FSC_FTK);
/* fast log_sect % 128 */
cqd_context->rd_wr_op.d_sect = (dUByte)((log_sect % FSC_FTK) + 1);
cqd_context->rd_wr_op.s_sect = (dUByte)cqd_context->rd_wr_op.d_sect;
/* Next, we need the tape positioning data. This is the data that */
/* we need to find out where, physically, on the tape we need to be. */
/* The tape track is determined first as */
/* (logical sector number) / (floppy sectors per tape track). The */
/* remainder from this calculation is the absolute sector number */
/* on the tape track. Lastly, the physical segment is determined by */
/* dividing the physical sector number by the number of sectors per */
/* segment. */
log_sect = block;
cqd_context->rd_wr_op.d_track = 0;
if (cqd_context->floppy_tape_parms.fsect_ttrack != 0) {
cqd_context->rd_wr_op.d_track =
(dUWord)(log_sect / cqd_context->floppy_tape_parms.fsect_ttrack);
log_sect = log_sect % cqd_context->floppy_tape_parms.fsect_ttrack;
} else {
return kdi_Error(ERR_UNKNOWN_TAPE_LENGTH, FCT_ID, ERR_SEQ_2);
}
cqd_context->rd_wr_op.d_segment = log_sect / FSC_SEG;
/* Finally, if the IO Request requests a read that will cross a segment */
/* boundary then an error is returned. */
if ((((cqd_context->rd_wr_op.d_sect - 1) & SEGMENT_MASK) + number) >
cqd_context->floppy_tape_parms.fsect_seg) {
return kdi_Error(ERR_BAD_REQUEST, FCT_ID, ERR_SEQ_2);
}
return status;
}