_WCRTLINK int chsize( int handle, long size )
{
long curOffset, endOffset;
char buf[512];
long diff;
unsigned amount;
int retCode;
__handle_check( handle, -1 );
/*** Prepare to change the size ***/
_AccessFileH( handle );
curOffset = __lseek( handle, 0L, SEEK_CUR ); /* get current offset */
if( curOffset == -1 ) {
_ReleaseFileH( handle );
return( -1 );
}
endOffset = __lseek( handle, 0L, SEEK_END ); /* get file size */
if( endOffset == -1 ) {
_ReleaseFileH( handle );
return( -1 );
}
if( size > endOffset ) {
/*** Increase file size ***/
diff = size - endOffset; /* number of bytes to pad */
memset( buf, 0, 512 ); /* zero buffer */
do {
if( diff >= 512 ) {
amount = 512;
} else {
amount = (unsigned)diff;
}
retCode = write( handle, buf, amount );
if( retCode != amount ) {
__set_errno( ENOSPC );
retCode = -1;
break;
}
diff -= amount;
} while( diff != 0 );
if( retCode != -1 ) retCode = 0;
} else {
/*** Shrink file ***/
retCode = DosNewSize( handle, size );
if( retCode != 0 ) {
__set_errno_dos( retCode );
retCode = -1;
}
if( curOffset > size ) curOffset = size;
}
/*** Clean up and go home ***/
curOffset = __lseek( handle, curOffset, SEEK_SET );
if( curOffset == -1 ) retCode = -1;
_ReleaseFileH( handle );
return( retCode );
}
int _fast setfsize(int fd, long size)
{
return ((int)DosNewSize((HFILE)fd, (ULONG)size));
}
