Category : C Source Code
Archive   : TIFTOOL.ZIP
Filename : VIO.C

/* vio.c - virtual pseudo-file i/o
*/

#include "aldtypes.h" /* for WORD, DWORD, LPSTR, etc */
#include "aldutils.h" /* for copy prototype */
#include "imtypes.h"

#include "stdio.h"
#include "dloc.h"
#include "vio.h"

#ifdef MACINTOSH
int fseek (FILE *, long, int);
int fread (char *, int, int, FILE *);
#endif

extern DWORD TiffStart;

/*************** LOCAL routines ***********************/


/******************** external routines **********************/

RC VRead (pD, pos, BytesToRead, lpBuf)
PDLOC pD; /* pointer to a structure that tells
* where to go for the information
*/
DWORD pos; /* byte position, with respect to the beginning
* of the "file", to start reading data from
*/
WORD BytesToRead;
LPSTR lpBuf; /* where to put the data */
{
register DLOC *pDloc = (DLOC *)pD;
RC err = SUCCESS;
int red;

/* DBMSG(("VRead: top. %u\n", BytesToRead)); */

if (pDloc->dlWhere == INFILE) {
if (err = fseek (pDloc->dlFp, (long) (pos+TiffStart), 0)) {
DBMSG(( "VRead: fseek error\n"));
DBMSG((" err=%u pos=%lu BytesToRead=%u\n",
err,pos,BytesToRead));
return err;
}
if ((red = fread (lpBuf, 1, BytesToRead, pDloc->dlFp)) == 0) {
DBMSG(( "VRead: fread error\n"));
DBMSG((" err=%u pos=%lu BytesToRead=%u\n",
err,pos,BytesToRead));
return -1;
}
/* ByteHexDump (BytesToRead, (LPBYTE)lpBuf); */

} else {
DBMSG(("VRead: bad dlWhere\n"));
err = -1;
}

cu0: /* DBMSG(("VRead: bottom\n")); */
return err;
}