RWops.hh

/*
  libSDL2pp - C++ bindings/wrapper for SDL2
  Copyright (C) 2014-2015 Dmitry Marakasov <amdmi3@amdmi3.ru>
 
  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.
 
  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:
 
  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
 
#ifndef SDL2PP_RWOPS_HH
#define SDL2PP_RWOPS_HH
 
#include <string>
 
#include <SDL_rwops.h>
#include <SDL2pp/Exception.hh>
#include <SDL2pp/Export.hh>
 
namespace SDL2pp {
 
class SDL2PP_EXPORT CustomRWops {
public:
    virtual ~CustomRWops() {}
 
    virtual Sint64 Size() = 0;
 
    virtual Sint64 Seek(Sint64 offset, int whence) = 0;
 
 
    virtual size_t Read(void* ptr, size_t size, size_t maxnum) = 0;
    virtual size_t Write(const void* ptr, size_t size, size_t num) = 0;
 
    virtual int Close() = 0;
};
 
class SDL2PP_EXPORT RWops {
protected:
    SDL_RWops* rwops_; 
 
private:
    static Sint64 StdSizeFuncWrapper(SDL_RWops* context);
    static Sint64 StdSeekFuncWrapper(SDL_RWops* context, Sint64 offset, int whence);
    static size_t StdReadFuncWrapper(SDL_RWops* context, void *ptr, size_t size, size_t maxnum);
    static size_t StdWriteFuncWrapper(SDL_RWops* context, const void *ptr, size_t size, size_t maxnum);
    static int StdCloseFuncWrapper(SDL_RWops* context);
 
    static Sint64 CustomSizeFuncWrapper(SDL_RWops* context);
    static Sint64 CustomSeekFuncWrapper(SDL_RWops* context, Sint64 offset, int whence);
    static size_t CustomReadFuncWrapper(SDL_RWops* context, void *ptr, size_t size, size_t maxnum);
    static size_t CustomWriteFuncWrapper(SDL_RWops* context, const void *ptr, size_t size, size_t maxnum);
    static int CustomCloseFuncWrapper(SDL_RWops* context);
 
    static RWops CheckedCreateStandardRWops(SDL_RWops* sdl_rwops, const char* errmsg);
 
public:
    static RWops FromFP(FILE* file, bool autoclose);
 
    static RWops FromConstMem(const void* mem, int size);
 
    static RWops FromMem(void* mem, int size);
 
    static RWops FromFile(const std::string& file, const std::string& mode = "rb");
 
    explicit RWops(SDL_RWops* rwops);
 
    RWops(RWops&& other) noexcept;
 
    RWops& operator=(RWops&& other) noexcept;
 
    RWops(const RWops&) = delete;
 
    RWops& operator=(const RWops&) = delete;
 
    template<class C>
    explicit RWops(C&& custom_rwops) {
        rwops_ = SDL_AllocRW();
        if (rwops_ == nullptr)
            throw Exception("SDL_AllocRW");
 
        rwops_->size = CustomSizeFuncWrapper;
        rwops_->seek = CustomSeekFuncWrapper;
        rwops_->read = CustomReadFuncWrapper;
        rwops_->write = CustomWriteFuncWrapper;
        rwops_->close = CustomCloseFuncWrapper;
        rwops_->type = 0x57524370; // "pCRW" for libSDLp[p] [C]ustom [RW]ops
        try {
            rwops_->hidden.unknown.data1 = static_cast<void*>(new C(std::move(custom_rwops)));
        } catch (...) {
            SDL_FreeRW(rwops_);
            throw;
        }
        rwops_->hidden.unknown.data2 = static_cast<void*>(this);
    }
 
    ~RWops();
 
    SDL_RWops* Get() const;
 
    int Close();
 
    size_t Read(void* ptr, size_t size, size_t maxnum);
 
    Sint64 Seek(Sint64 offset, int whence);
 
    size_t Write(const void* ptr, size_t size, size_t num);
 
    Sint64 Tell();
 
    Sint64 Size();
 
    Uint16 ReadBE16();
 
    Uint32 ReadBE32();
 
    Uint64 ReadBE64();
 
    Uint16 ReadLE16();
 
    Uint32 ReadLE32();
 
    Uint64 ReadLE64();
 
    size_t WriteBE16(Uint16 value);
 
    size_t WriteBE32(Uint32 value);
 
    size_t WriteBE64(Uint64 value);
 
    size_t WriteLE16(Uint16 value);
 
    size_t WriteLE32(Uint32 value);
 
    size_t WriteLE64(Uint64 value);
};
 
}
 
#endif