CnC_Remastered_Collection/REDALERT/CSTRAW.CPP

98 lines
5.5 KiB
C++

//
// Copyright 2020 Electronic Arts Inc.
//
// TiberianDawn.DLL and RedAlert.dll and corresponding source code is free
// software: you can redistribute it and/or modify it under the terms of
// the GNU General Public License as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
// TiberianDawn.DLL and RedAlert.dll and corresponding source code is distributed
// in the hope that it will be useful, but with permitted additional restrictions
// under Section 7 of the GPL. See the GNU General Public License in LICENSE.TXT
// distributed with this program. You should have received a copy of the
// GNU General Public License along with permitted additional restrictions
// with this program. If not, see https://github.com/electronicarts/CnC_Remastered_Collection
/* $Header: /CounterStrike/CSTRAW.CPP 1 3/03/97 10:24a Joe_bostic $ */
/***********************************************************************************************
*** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S ***
***********************************************************************************************
* *
* Project Name : Command & Conquer *
* *
* File Name : CSTRAW.CPP *
* *
* Programmer : Joe L. Bostic *
* *
* Start Date : 11/10/96 *
* *
* Last Update : November 10, 1996 [JLB] *
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* CacheStraw::Get -- Fetch data from the data source. *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#include "cstraw.h"
#include <string.h>
/***********************************************************************************************
* CacheStraw::Get -- Fetch data from the data source. *
* *
* This will supply the data quantity requested. It performs a regulating influence on the *
* data requests passed through it. The data is requested from the next straw in the *
* chain such that the data stream is requested in chunks. This serves to lessen the *
* impact of multiple small data requests. *
* *
* INPUT: source -- Pointer to the buffer to hold the data. *
* *
* slen -- The number of data bytes requested. *
* *
* OUTPUT: Returns with the number of data bytes stored into the buffer specified. If this *
* number is less than that requested, it indicates that the data source has been *
* exhausted. *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 11/10/1996 JLB : Created. *
*=============================================================================================*/
int CacheStraw::Get(void * source, int slen)
{
int total = 0;
if (Is_Valid() && source != NULL && slen > 0) {
/*
** Keep processing the data request until there is no more data to supply or the request
** has been fulfilled.
*/
while (slen > 0) {
/*
** First try to fetch the data from data previously loaded into the buffer.
*/
if (Length > 0) {
int tocopy = (Length < slen) ? Length : slen;
memmove(source, ((char *)BufferPtr.Get_Buffer()) + Index, tocopy);
slen -= tocopy;
Index += tocopy;
total += tocopy;
Length -= tocopy;
source = (char*)source + tocopy;
}
if (slen == 0) break;
/*
** Since there is more to be fulfilled yet the holding buffer is empty,
** refill the buffer with a fresh block of data from the source.
*/
Length = Straw::Get(BufferPtr, BufferPtr.Get_Size());
Index = 0;
if (Length == 0) break;
}
}
return(total);
}