equalfile

README

About Equalfile

Equalfile is a pure Go package for comparing files.

Install

Recipe with Modules (since Go 1.11)

Clone outside of GOPATH:

git clone https://github.com/udhos/equalfile
cd equalfile

Install example application 'equal':

go install ./equal

Run example application:

~/go/bin/equal

Recipe without Modules (before Go 1.11)

Set up GOPATH as usual:

export GOPATH=$HOME/go
mkdir $GOPATH

Get equalfile package:

go get github.com/udhos/equalfile

Install example application 'equal':

go install github.com/udhos/equalfile/equal

Run example application:

$GOPATH/bin/equal

Usage

Add the import path:

import "github.com/udhos/equalfile"

See: equalfile GoDoc API

Example Application

See example application: equal source code

Documentation

Overview

Package equalfile provides facilities for comparing files.

Equalfile is similar to Python's filecmp:

import filecmp
if filecmp.cmp(filename1, filename2, shallow=False):

Comparing only two files

In single mode, equalfile compares files byte-by-byte.

import "github.com/udhos/equalfile"
// ...
cmp := equalfile.New(nil, equalfile.Options{}) // compare using single mode
equal, err := cmp.CompareFile("file1", "file2")

Comparing multiple files

In multiple mode, equalfile records files hashes in order to speedup repeated comparisons. You must provide the hashing function.

import "crypto/sha256"
import "github.com/udhos/equalfile"
// ...
cmp := equalfile.NewMultiple(nil, equalfile.Options{}, sha256.New(), true) // enable multiple mode
equal, err := cmp.CompareFile("file1", "file2")

Index

• type Cmp
  • func New(buf []byte, options Options) *Cmp
  • func NewMultiple(buf []byte, options Options, h hash.Hash, compareOnMatch bool) *Cmp
  • func (c *Cmp) CompareFile(path1, path2 string) (bool, error)
  • func (c *Cmp) CompareReader(r1, r2 io.Reader) (bool, error)
• type Options

Types

type Cmp

type Cmp struct {
	Opt Options
	// contains filtered or unexported fields
}

func New

func New(buf []byte, options Options) *Cmp

New creates Cmp for single comparison mode.

func NewMultiple

func NewMultiple(buf []byte, options Options, h hash.Hash, compareOnMatch bool) *Cmp

New creates Cmp for multiple comparison mode.

func (*Cmp) CompareFile

func (c *Cmp) CompareFile(path1, path2 string) (bool, error)

CompareFile verifies that files with names path1, path2 have same contents.

func (*Cmp) CompareReader

func (c *Cmp) CompareReader(r1, r2 io.Reader) (bool, error)

CompareReader verifies that two readers provide same content.

type Options

type Options struct {
	Debug         bool  // enable debugging to stdout
	ForceFileRead bool  // prevent shortcut at filesystem level (link, pathname, etc)
	MaxSize       int64 // prevent forever reading from an infinite reader
}