From 738520bbdbe9ced7ce8fc4bb493353d6e289ce92e723c2ef6667dbf59dc7adab Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Sat, 12 Aug 2023 12:17:32 +0300
Subject: [PATCH 1/1] Initial commit

---
 go.mod        |  3 ++
 netrc.go      | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++
 netrc_test.go | 53 +++++++++++++++++++++++++++++
 3 files changed, 148 insertions(+)
 create mode 100644 go.mod
 create mode 100644 netrc.go
 create mode 100644 netrc_test.go

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..b191185
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module go.cypherpunks.ru/netrc
+
+go 1.20
diff --git a/netrc.go b/netrc.go
new file mode 100644
index 0000000..53521d2
--- /dev/null
+++ b/netrc.go
@@ -0,0 +1,92 @@
+// netrc -- parse .netrc file
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// netrc library parses .netrc file. It is copy-paste of
+// golang.org/x/tools/cmd/auth/netrcauth.
+//
+// See https://www.gnu.org/software/inetutils/manual/html_node/The-_002enetrc-file.html
+// for documentation on the .netrc format.
+package netrc
+
+import (
+	"os"
+	"path"
+	"strings"
+)
+
+type Line struct {
+	Machine  string
+	Login    string
+	Password string
+}
+
+func Parse(data string) []Line {
+	var nrc []Line
+	var l Line
+	inMacro := false
+	for _, line := range strings.Split(data, "\n") {
+		if inMacro {
+			if line == "" {
+				inMacro = false
+			}
+			continue
+		}
+		f := strings.Fields(line)
+		i := 0
+		for ; i < len(f)-1; i += 2 {
+			// Reset at each "machine" token.
+			// "The auto-login process searches the .netrc file for a machine token
+			// that matches […]. Once a match is made, the subsequent .netrc tokens
+			// are processed, stopping when the end of file is reached or another
+			// machine or a default token is encountered."
+			switch f[i] {
+			case "machine":
+				l = Line{Machine: f[i+1]}
+			case "default":
+				break
+			case "login":
+				l.Login = f[i+1]
+			case "password":
+				l.Password = f[i+1]
+			case "macdef":
+				// "A macro is defined with the specified name; its contents begin with
+				// the next .netrc line and continue until a null line (consecutive
+				// new-line characters) is encountered."
+				inMacro = true
+			}
+			if l.Machine != "" && l.Login != "" && l.Password != "" {
+				nrc = append(nrc, l)
+				l = Line{}
+			}
+		}
+		if i < len(f) && f[i] == "default" {
+			// "There can be only one default token, and it must be after all machine tokens."
+			break
+		}
+	}
+	return nrc
+}
+
+func Path() (netrc string) {
+	p, ok := os.LookupEnv("NETRC")
+	if ok {
+		return p
+	}
+	homeDir, _ := os.UserHomeDir()
+	return path.Join(homeDir, ".netrc")
+}
+
+func Find(host string) (login string, password string) {
+	data, err := os.ReadFile(Path())
+	if err != nil {
+		return "", ""
+	}
+	for _, l := range Parse(string(data)) {
+		if l.Machine == host {
+			return l.Login, l.Password
+		}
+	}
+	return "", ""
+}
diff --git a/netrc_test.go b/netrc_test.go
new file mode 100644
index 0000000..7fe98c2
--- /dev/null
+++ b/netrc_test.go
@@ -0,0 +1,53 @@
+package netrc
+
+import (
+	"reflect"
+	"testing"
+)
+
+var testNetrc = `
+machine incomplete
+password none
+
+machine api.github.com
+  login user
+  password pwd
+
+machine incomlete.host
+  login justlogin
+
+machine test.host
+login user2
+password pwd2
+
+machine oneline login user3 password pwd3
+
+machine ignore.host macdef ignore
+  login nobody
+  password nothing
+
+machine hasmacro.too macdef ignore-next-lines login user4 password pwd4
+  login nobody
+  password nothing
+
+default
+login anonymous
+password gopher@golang.org
+
+machine after.default
+login oops
+password too-late-in-file
+`
+
+func TestParse(t *testing.T) {
+	lines := Parse(testNetrc)
+	want := []Line{
+		{"api.github.com", "user", "pwd"},
+		{"test.host", "user2", "pwd2"},
+		{"oneline", "user3", "pwd3"},
+		{"hasmacro.too", "user4", "pwd4"},
+	}
+	if !reflect.DeepEqual(lines, want) {
+		t.Errorf("have %q\nwant %q", lines, want)
+	}
+}
-- 
2.44.0