0ad/source/lib/file/io/io.h
2010-02-08 16:23:39 +00:00

56 lines
2.4 KiB
C

/* Copyright (c) 2010 Wildfire Games
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* IO manager: splits requests into asynchronously issued blocks,
* thus simplifying caching and enabling periodic callbacks.
*/
#ifndef INCLUDED_IO
#define INCLUDED_IO
#include "lib/file/file.h"
// memory will be allocated from the heap, not the (limited) file cache.
// this makes sense for write buffers that are never used again,
// because we avoid having to displace some other cached items.
LIB_API shared_ptr<u8> io_Allocate(size_t size, off_t ofs = 0);
/**
* called after a block IO has completed.
*
* @return INFO::CB_CONTINUE to continue; any other value will cause the
* IO splitter to abort immediately and return that.
*
* this is useful for user progress notification or processing data while
* waiting for the next I/O to complete (without the complexity of threads).
**/
typedef LibError (*IoCallback)(uintptr_t cbData, const u8* block, size_t blockSize);
LIB_API LibError io_Scan(const PFile& file, off_t ofs, off_t size, IoCallback cb, uintptr_t cbData);
LIB_API LibError io_Read(const PFile& file, off_t ofs, u8* alignedBuf, off_t size, u8*& data);
LIB_API LibError io_WriteAligned(const PFile& file, off_t alignedOfs, const u8* alignedData, off_t size);
LIB_API LibError io_ReadAligned(const PFile& file, off_t alignedOfs, u8* alignedBuf, off_t size);
#endif // #ifndef INCLUDED_IO