mgl_file_delegate_posix.h

[詳解]

// SPDX-License-Identifier: Zlib
/* ------------------------------------------------------------------------- */
/* ------------------------------------------------------------------------- */
 
#ifndef INCGUARD_MGL_FILE_DELEGATE_POSIX_H_1611110145
#define INCGUARD_MGL_FILE_DELEGATE_POSIX_H_1611110145
 
#include <mgl/mgl_environment.h>
#if defined(MGL_FILE_DELEGATE_ENABLE_POSIX)
 
#include <cstdio>
 
#include <mgl/file/mgl_file_delegate.h>
 
namespace MGL::File
{
class POSIXDelegate : public Delegate
{
public:
    static constexpr DelegateKey kDelegateKey = MakeDelegateKey("MGL-POSIX");
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    [[nodiscard]] bool IsManagedSystemNativeFile() const noexcept override
    {
        return true;    // 扱う
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    [[nodiscard]] bool IsWritable() const noexcept override
    {
        return true;    // 対応している
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    Result Mount([[maybe_unused]] SharedMountWork &mountWork, [[maybe_unused]] const PathView &path, [[maybe_unused]] MountAccessType accessType) noexcept override
    {
        return Result::Succeeded();    // このデリゲートはマウントワークを使用しないので何もせずに成功を返す
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    void Unmount([[maybe_unused]] SharedMountWork &mountWork) noexcept override
    {
    }
 
    AccessWorkPtr Open(Result &result, SharedMountWork &mountWork, const PathView &path, OpenMode mode) noexcept override;
    Result Close(AccessWork *work) noexcept override;
    size_t Read(AccessWork *work, Result &result, void *buffer, size_t size) noexcept override;
    size_t Write(AccessWork *work, Result &result, const void *buffer, size_t size) noexcept override;
    size_t Seek(AccessWork *work, Result &result, SeekType seekType, int32_t offset) noexcept override;
    size_t GetOffset(AccessWork *work, Result &result) const noexcept override;
    bool IsEOF(AccessWork *work, Result &result) const noexcept override;
    size_t GetSize(AccessWork *work, Result &result) const noexcept override;
    size_t GetSize(MountWork *mountWork, Result &result, const PathView &path) const noexcept override;
    Result MakeDirectory(MountWork *mountWork, const PathView &path) noexcept override;
    Result Move(MountWork *mountWork, const PathView &sourcePath, const PathView &destPath) noexcept override;
    Result Remove(MountWork *mountWork, const PathView &path) noexcept override;
    bool Exists(MountWork *mountWork, Result &result, const PathView &path) noexcept override;
 
    struct POSIXWork : public AccessWork
    {
        FILE *fp{nullptr};    
        size_t size{0};       
 
        POSIXWork(OpenMode mode) noexcept
            : AccessWork(mode, kDelegateKey)
        {
        }
    };
 
protected:
    static POSIXWork *GetWork(AccessWork *work, OpenMode mode = OpenMode::None) noexcept;
    [[nodiscard]] static const char *GetModeString(OpenMode mode) noexcept;
    [[nodiscard]] static Error GetError(int errorNumber) noexcept;
};
}    // namespace MGL::File
 
#endif    // MGL_FILE_DELEGATE_ENABLE_POSIX
#endif    // INCGUARD_MGL_FILE_DELEGATE_POSIX_H_1611110145
 
// vim: et ts=4 sw=4 sts=4