insrec.c

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	insrec.c (file)
 *
 *	File management
 *	Insert/Add/Delete records.
 */

#include "fileio.h"
#include "diskio.h"

LOCAL ER changeRecordCount( OFCB *ofcb, W rtype, W diff );
LOCAL WER changeFileReferenceCount( FID fid, W diff, FsInfo *fsinfo );
LOCAL ER checkLINK( LINK *lnk, FsInfo *fsinfo );
LOCAL ER appendRecord( RCB **rcb, OFCB *ofcb, W type, UH subtype, LINK *lnk );
LOCAL ER insertRecord( RCB **rcb, OFCB *ofcb, W type, UH subtype, LINK *lnk );
LOCAL WER deleteRecord( FD *fd, RCB *rcb, OFCB *ofcb );

#define TSD_FRC_VAL_255	255
#define TSD_FPR_VAL_32	32
#define TSD_FRC_VAL_M1	(-1)
#define TSD_DRD_VAL_M1	(-1)

/*
 * Update the total number of records.
 *	Increase/Decrease the total number of records of the file header by diff.
 *	In the case of the link record, increase/decrease the number of included links as well.
 */
LOCAL ER changeRecordCount( OFCB *ofcb, W rtype, W diff )
{
	FsInfo		*fsinfo = ofcb->fsinfo;
	DfFileHeader	*fh;
	H		nlnk;
	ID		mid;
	ER		err;

	/* Map the file header. */
	fh = fmpMapDskAdr(ofcb->fhead, sizeof(DfFileHeader),
					ofcb, &mid, fsinfo);
	if ( fh == NULL ) {
		err = (ER)mid;
		goto err_ret;
	}

	/* Update the total number of records. */
	ofcb->nrec += diff;
	fh->nrec = (W)fmpConvEndianW((UW)ofcb->nrec, fsinfo);

	if ( isLinkRecord(rtype) != 0 ) {
		/* Update the number of included links. */
		nlnk = (H)fmpConvEndianH((UH)fh->nlnk, fsinfo) + (H)diff;
		fh->nlnk = (H)fmpConvEndianH((UH)nlnk, fsinfo);
	}

	fmpUnmapDisk(mid, MD_WRITE);
	err = fmpCheckDiskError(ofcb, fsinfo);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("changeRecordCount err = %d\n", err));
	return err;
}

/*
 * Update the file reference count.
 *	Increase/Decrease the reference count of the file ID table by diff.
 *	Return the updated reference count.
 */
LOCAL WER changeFileReferenceCount( FID fid, W diff, FsInfo *fsinfo )
{
	W		refcnt;
	DfFileID	*fidt, f;
	DfFileHeader	*fh = NULL;
	ID		mid, mid2;
	ER		err;

	/* Map the file ID table. */
	fidt = fmpMapFileID(fid, &mid, fsinfo);
	if ( fidt == NULL ) {
		err = (ER)mid;
		goto err_ret1;
	}

	if ( fidt->w == 0U ) {
		/* File does not exist. */
		err = E_NOEXS;
		goto err_ret2;
	}

	f = fmpConvEndianFileID(*fidt, fsinfo);
	refcnt = (W)f.s.refcnt;

	if ( ((refcnt == TSD_FRC_VAL_255) || ((refcnt + diff) >= TSD_FRC_VAL_255))
	  && (fsinfo->diskform >= DiskForm_B) ) {
		/* Map the file header. */
		fh = fmpMapDskAdr(fmpLBlkToDAdr(f.s.blkadr, fsinfo),
			sizeof(DfFileHeader), MAP_FSTSK, &mid2, fsinfo);
		if ( fh == NULL ) {
			err = (ER)mid2;
			goto err_ret2;
		}

		if ( refcnt == TSD_FRC_VAL_255 ) {
			/* File reference count in STDFS extended format (>=255) */
			refcnt = (W)fmpConvEndianW((UW)fh->refcnt, fsinfo);
		}
	}

	refcnt += diff;

	if ( (refcnt < 0)
	  || ((refcnt > TSD_FRC_VAL_255) && (fsinfo->diskform == DiskForm_A)) ) {
		/* The reference count overflowed. */
		err = E_LIMIT;
		goto err_ret3;
	}

	if ( fh != NULL ) {
		/* File the reference count in STDFS extended format (>=255) */
		fh->refcnt = (W)fmpConvEndianW(( refcnt >= TSD_FRC_VAL_255 )? (UW)refcnt: 0,
								fsinfo);

		fmpUnmapDisk(mid2, MD_WRITE);
	}

	/* Update the file reference count */
	f.s.refcnt = (UB)(( refcnt >= TSD_FRC_VAL_255 )? TSD_FRC_VAL_255: refcnt);
	*fidt = fmpConvEndianFileID(f, fsinfo);

	fmpUnmapDisk(mid, MD_WRITE);
	err = fmpCheckDiskError(NULL, fsinfo);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	return refcnt;

err_ret3:
	fmpUnmapDisk(mid2, MD_RDONLY);
err_ret2:
	fmpUnmapDisk(mid, MD_RDONLY);
err_ret1:
	DEBUG_PRINT(("changeFileReferenceCount err = %d\n", err));
	return err;
}

/*
 * Check the contents of LINK.
 * If correct, up the reference count.
 */
LOCAL ER checkLINK( LINK *lnk, FsInfo *fsinfo )
{
	ER		err;

	/* Check the file system. */
	if ( tc_strncmp(lnk->fs_name, fsinfo->fsName, FsNameLen) != 0 ) {
		/* The file system is different. */
		err = E_REC;
		goto err_ret;
	}

	/* Up the file reference count. */
	err = changeFileReferenceCount(lnk->f_id, +1, fsinfo);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("checkLINK err = %d\n", err));
	return err;
}

/*
 * Add the record.
 *	Add new record just before the end record.
 *	Return the RCB of the added new record to *rcb.
 */
LOCAL ER appendRecord( RCB **rcb, OFCB *ofcb, W type, UH subtype, LINK *lnk )
{
	RIdx		ri;
	RCB		*newrcb;
	DfRecordIndex	*ridx;
	ER		err;

	/* Locate ri at the last record index. */
	err = fmpOpenRIdx(&ri, LAST_RIdx, ofcb);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	ridx = fmpGetRIdx(&ri);
	if ( ridx == NULL ) {
		goto err_ret3;
	}

	/* Whether the current location is an unused record index. */
	if ( !((ridx->type[0] == 0) && (ridx->type[1] == 0)) ) {
		/* It is used. */

		RCB *currcb = prevRCB(EndRCB(ofcb));
		err = fmpSetRCB(currcb, ofcb);
		if ( err < E_OK ) {
			goto err_ret2;
		}

		/* Add the record index. */
		ridx = fmpAppendRIdx(&ri, currcb);
		if ( ridx == NULL ) {
			goto err_ret3;
		}
	}

	/* Add the new RCB just before the end record. */
	err = fmpNewRCB(EndRCB(ofcb));
	if ( err < E_OK ) {
		goto err_ret2;
	}

	/* Initialize the record index. */
	err = fmpSetRIdx(&ri, type, subtype, lnk);
	if ( err < E_OK ) {
		goto err_ret2;
	}

	err = fmpCloseRIdx(&ri);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	/* Update the total number of records of the file header. */
	err = changeRecordCount(ofcb, type, +1);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	/* Initialize the added RCB. */
	newrcb = prevRCB(EndRCB(ofcb));
	err = fmpSetRCB(newrcb, ofcb);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	*rcb = newrcb;
	return E_OK;

err_ret3:
	err = fmpGetRIdxError(&ri);
err_ret2:
	(void)fmpCloseRIdx(&ri);
err_ret1:
	DEBUG_PRINT(("appendRecord err = %d\n", err));
	return err;
}

/*
 * Insert the record.
 *	Insert the new record just before *rcb.
 *	*rcb must not be the end record.
 *	Return the RCB of the inserted new record to *rcb.
 */
LOCAL ER insertRecord( RCB **rcb, OFCB *ofcb, W type, UH subtype, LINK *lnk )
{
	RIdx		ri;
	RCB		*currcb = *rcb;
	RCB		*newrcb;
	DfRecordIndex	*ridx;
	ER		err;

	/* Locate ri at the first record index of currcb. */
	err = fmpOpenRIdx(&ri, &currcb->idxadr, ofcb);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	ridx = fmpGetRIdx(&ri);
	if ( ridx == NULL ) {
		goto err_ret3;
	}

	/* Insert the record index. */
	ridx = fmpInsertRIdx(&ri, currcb);
	if ( ridx == NULL ) {
		goto err_ret3;
	}

	/* Insert the new RCB just before currcb. */
	err = fmpNewRCB(currcb);
	if ( err < E_OK ) {
		goto err_ret2;
	}

	/* Increase the record numbers after currcb by 1. */
	fmpIncRNoRCB(currcb, ofcb);

	/* Initialize the record index. */
	err = fmpSetRIdx(&ri, type, subtype, lnk);
	if ( err < E_OK ) {
		goto err_ret2;
	}

	err = fmpCloseRIdx(&ri);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	/* Update the total number of records of the file header. */
	err = changeRecordCount(ofcb, type, +1);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	/* Initialize the inserted RCB. */
	newrcb = prevRCB(currcb);
	err = fmpSetRCB(newrcb, ofcb);
	if ( err < E_OK ) {
		goto err_ret1;
	}

	*rcb = newrcb;
	return E_OK;

err_ret3:
	err = fmpGetRIdxError(&ri);
err_ret2:
	(void)fmpCloseRIdx(&ri);
err_ret1:
	DEBUG_PRINT(("insertRecord err = %d\n", err));
	return err;
}

/*
 * Insert the record.
 */
EXPORT void fmpInsertRecord( FmCmdPkt *pkt )
{
	FM_INS_REC_PARA	*cmdPara = (FM_INS_REC_PARA*)pkt->cmd.para;
	FD		*fd;
	OFCB		*ofcb;
	RCB		*rcb;
	ER		err, error = E_OK;

	/* Obtain FD and OFCB. */
	fd = getFDp(cmdPara->fd);
	ofcb = fd->ofcb;

	/* Check the open mode. */
	err = fmpCheckFileOpenMode(fd, F_WRITE);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Parameter check */
	if ( !((cmdPara->type >= 0) && (cmdPara->type < TSD_FPR_VAL_32))
	   || (cmdPara->size < 0) ) {
		err = E_PAR;
		goto err_ret;
	}

	if ( isLinkRecord(cmdPara->type) != 0 ) {
		/* Check when the link record is inserted. */
		if ( ((UW)cmdPara->size != sizeof(LINK))
		  || (cmdPara->buf == NULL) ) {
			err = E_PAR;
			goto err_ret;
		}

		err = CheckSpaceR(cmdPara->buf, sizeof(LINK));
		if ( err < E_OK ) {
			goto err_ret;
		}

		/* Check the contents of LINK. */
		err = checkLINK((LINK*)cmdPara->buf, ofcb->fsinfo);
		if ( err < E_OK ) {
			goto err_ret;
		}
	}

	/* Obtain the current record. */
	rcb = fd->crcb;
	if ( !isEndRCB(rcb, ofcb) ) {
		err = fmpSetRCB(rcb, ofcb);
		if ( err < E_OK ) {
			goto err_ret;
		}

		/* Insert the record. */
		err = insertRecord(&rcb, ofcb,
			cmdPara->type, cmdPara->subtype, (LINK*)cmdPara->buf);
		if ( err < E_OK ) {
			goto err_ret;
		}
	} else {
		/* Add the record. */
		err = appendRecord(&rcb, ofcb,
			cmdPara->type, cmdPara->subtype, (LINK*)cmdPara->buf);
		if ( err < E_OK ) {
			goto err_ret;
		}
	}

	if ( isDataRecord(cmdPara->type) && (cmdPara->size > 0) ) {

		/* Write the data record. */
		err = fmpWriteDataRecord(rcb, ofcb,
			0, cmdPara->buf, cmdPara->size, cmdPara->units);
		if ( err < E_OK ) {
			if ( err != E_NODSK ) {
				goto err_ret;
			}
			error = err;
		}
	}

	/* Update the time stamp. */
	err = fmpSetTimeStamp(ofcb, F_WRITE);