37 lines
1.1 KiB
Go
37 lines
1.1 KiB
Go
// Copyright Terence J. Boldt (c)2021-2023
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// Use of this source code is governed by an MIT
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// license that can be found in the LICENSE file.
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// This file provides a file in memory
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package prodos
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// MemoryFile containts file data and size
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type MemoryFile struct {
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data []byte
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size int
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}
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// ReaderWriterAt is an interface for both ReaderAt and WriterAt combined
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type ReaderWriterAt interface {
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ReadAt(data []byte, offset int64) (int, error)
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WriteAt(data []byte, offset int64) (int, error)
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}
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// NewMemoryFile creates an in-memory file of the specified size in bytes
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func NewMemoryFile(size int) *MemoryFile {
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return &MemoryFile{make([]byte, size), size}
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}
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// WriteAt writes data to the specified offset in the file
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func (memoryFile *MemoryFile) WriteAt(data []byte, offset int64) (int, error) {
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copy(memoryFile.data[int(offset):], data)
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return len(data), nil
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}
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// ReadAt reads data from the specified offset in the file
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func (memoryFile *MemoryFile) ReadAt(data []byte, offset int64) (int, error) {
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copy(data, memoryFile.data[int(offset):])
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return len(data), nil
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}
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