ml
63 lines
1.4 KiB
Go
63 lines
1.4 KiB
Go
package resource
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import (
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"bytes"
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"io"
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)
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// Block is one set of bytes stored in a resource.
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// The interpretation of the bytes is dependent on the content type of the resource.
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type Block []byte
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// Blocks is a list of blocks in memory.
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type Blocks struct {
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data [][]byte
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}
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// BlocksFrom returns a blocks instance from given data.
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func BlocksFrom(data [][]byte) Blocks {
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return Blocks{data: data}
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}
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// BlockCount returns the number of available blocks.
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func (blocks Blocks) BlockCount() int {
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return len(blocks.data)
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}
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// BlockRaw returns the raw byte slice stored in the identified block.
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func (blocks Blocks) BlockRaw(index int) ([]byte, error) {
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available := len(blocks.data)
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if (index < 0) || (index >= available) {
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return nil, ErrBlockNotFound(index, available)
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}
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return blocks.data[index], nil
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}
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// Block returns the reader for the identified block.
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// Each call returns a new reader instance.
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func (blocks Blocks) Block(index int) (io.Reader, error) {
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raw, err := blocks.BlockRaw(index)
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if err != nil {
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return nil, err
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}
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return bytes.NewBuffer(raw), nil
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}
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// Set the data of all the blocks.
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func (blocks *Blocks) Set(data [][]byte) {
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blocks.data = data
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}
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// SetBlock sets the data of the identified block.
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func (blocks *Blocks) SetBlock(index int, data []byte) {
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if index < 0 {
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return
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}
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if index >= len(blocks.data) {
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newData := make([][]byte, index+1)
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copy(newData, blocks.data)
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blocks.data = newData
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}
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blocks.data[index] = data
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}
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