68 lines
1.5 KiB
C
68 lines
1.5 KiB
C
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//----------------------------------------------------------------------
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// This software is part of the OpenBeOS distribution and is covered
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// by the OpenBeOS license.
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//---------------------------------------------------------------------
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/*!
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\file OffsetFile.h
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OffsetFile interface declaration.
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*/
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#ifndef _OFFSET_FILE_H
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#define _OFFSET_FILE_H
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#include <DataIO.h>
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#include <File.h>
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namespace BPrivate {
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namespace Storage {
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/*!
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\class OffsetFile
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\brief Provides access to a file skipping a certain amount of bytes at
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the beginning.
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This class implements the BPositionIO interface to provide access to the
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data of a file past a certain offset. This is very handy e.g. for dealing
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with resources, as they always reside at the end of a file, but may start
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at arbitrary offsets.
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\author <a href='mailto:bonefish@users.sf.net'>Ingo Weinhold</a>
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\version 0.0.0
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*/
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class OffsetFile : public BPositionIO {
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public:
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OffsetFile();
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OffsetFile(BFile *file, off_t offset);
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virtual ~OffsetFile();
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status_t SetTo(BFile *file, off_t offset);
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void Unset();
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status_t InitCheck() const;
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BFile *File() const;
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ssize_t ReadAt(off_t pos, void *buffer, size_t size);
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ssize_t WriteAt(off_t pos, const void *buffer,
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size_t size);
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off_t Seek(off_t position, uint32 seekMode);
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off_t Position() const;
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status_t SetSize(off_t size);
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status_t GetSize(off_t *size);
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off_t Offset() const;
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private:
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BFile* fFile;
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off_t fOffset;
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off_t fCurrentPosition;
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};
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}; // namespace Storage
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}; // namespace BPrivate
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#endif // _OFFSET_FILE_H
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