go-ethereum/vendor/github.com/syndtr/goleveldb/leveldb/comparer/comparer.go
Péter Szilágyi 289b30715d Godeps, vendor: convert dependency management to trash (#3198)
This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.
2016-10-28 19:05:01 +02:00

58 lines
2.1 KiB
Go

// Copyright (c) 2012, 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 comparer provides interface and implementation for ordering
// sets of data.
package comparer
// BasicComparer is the interface that wraps the basic Compare method.
type BasicComparer interface {
// Compare returns -1, 0, or +1 depending on whether a is 'less than',
// 'equal to' or 'greater than' b. The two arguments can only be 'equal'
// if their contents are exactly equal. Furthermore, the empty slice
// must be 'less than' any non-empty slice.
Compare(a, b []byte) int
}
// Comparer defines a total ordering over the space of []byte keys: a 'less
// than' relationship.
type Comparer interface {
BasicComparer
// Name returns name of the comparer.
//
// The Level-DB on-disk format stores the comparer name, and opening a
// database with a different comparer from the one it was created with
// will result in an error.
//
// An implementation to a new name whenever the comparer implementation
// changes in a way that will cause the relative ordering of any two keys
// to change.
//
// Names starting with "leveldb." are reserved and should not be used
// by any users of this package.
Name() string
// Bellow are advanced functions used used to reduce the space requirements
// for internal data structures such as index blocks.
// Separator appends a sequence of bytes x to dst such that a <= x && x < b,
// where 'less than' is consistent with Compare. An implementation should
// return nil if x equal to a.
//
// Either contents of a or b should not by any means modified. Doing so
// may cause corruption on the internal state.
Separator(dst, a, b []byte) []byte
// Successor appends a sequence of bytes x to dst such that x >= b, where
// 'less than' is consistent with Compare. An implementation should return
// nil if x equal to b.
//
// Contents of b should not by any means modified. Doing so may cause
// corruption on the internal state.
Successor(dst, b []byte) []byte
}