scummvm/backends/plugins/elf/elf-loader.h
2011-08-07 13:53:33 +02:00

105 lines
3.1 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef BACKENDS_PLUGINS_ELF_LOADER_H
#define BACKENDS_PLUGINS_ELF_LOADER_H
#include "common/scummsys.h"
#if defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER)
#include <stddef.h>
#include "backends/plugins/elf/elf32.h"
#include "backends/plugins/dynamic-plugin.h"
#include "common/stream.h"
/**
* DLObject
*
* Class that most directly handles operations on a plugin file
* (opening it for reading, loading/unloading it in memory, finding a specific symbol in the file, etc.)
* Subclasses have the same functionality, but implementations specific to different processors/platforms.
*/
class DLObject {
protected:
Common::SeekableReadStream *_file;
byte *_segment;
Elf32_Sym *_symtab;
char *_strtab;
uint32 _segmentSize;
ptrdiff_t _segmentOffset;
uint32 _segmentVMA;
uint32 _symbol_cnt;
int32 _symtab_sect;
void *_dtors_start, *_dtors_end;
virtual void unload();
bool load();
bool readElfHeader(Elf32_Ehdr *ehdr);
bool readProgramHeaders(Elf32_Ehdr *ehdr, Elf32_Phdr *phdr, Elf32_Half num);
virtual bool loadSegment(Elf32_Phdr *phdr);
Elf32_Shdr *loadSectionHeaders(Elf32_Ehdr *ehdr);
int findSymbolTableSection(Elf32_Ehdr *ehdr, Elf32_Shdr *shdr);
int loadSymbolTable(Elf32_Ehdr *ehdr, Elf32_Shdr *shdr);
bool loadStringTable(Elf32_Shdr *shdr);
virtual void relocateSymbols(ptrdiff_t offset);
// architecture specific
/**
* Follow the instruction of a relocation section.
*
* @param fileOffset Offset into the File
* @param size Size of relocation section
* @param relSegment Base address of relocated segment in memory (memory offset)
*/
virtual bool relocate(Elf32_Off offset, Elf32_Word size, byte *relSegment) = 0;
virtual bool relocateRels(Elf32_Ehdr *ehdr, Elf32_Shdr *shdr) = 0;
// platform specific
virtual void flushDataCache(void *ptr, uint32 len) const = 0;
public:
DLObject();
virtual ~DLObject();
/**
* Test the size of the plugin in memory using the memory manager.
* @param path Path of file
*/
void trackSize(const char *path);
bool open(const char *path);
bool close();
void *symbol(const char *name);
void discardSymtab();
};
#endif /* defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) */
#endif /* BACKENDS_PLUGINS_ELF_LOADER_H */