Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/util/range.go


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// Copyright (c) 2014, Suryandaru Triandana <syndtr@gmail.com>
// All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package util

// Range is a key range.
type Range struct {
    // Start of the key range, include in the range.
    Start []byte

    // Limit of the key range, not include in the range.
    Limit []byte
}

// BytesPrefix returns key range that satisfy the given prefix.
// This only applicable for the standard 'bytes comparer'.
func BytesPrefix(prefix []byte) *Range {
    var limit []byte
    for i := len(prefix) - 1; i >= 0; i-- {
        c := prefix[i]
        if c < 0xff {
            limit = make([]byte, i+1)
            copy(limit, prefix)
            limit[i] = c + 1
            break
        }
    }
    return &Range{prefix, limit}
}