From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 15 Oct 2020 15:41:33 +0000 (+0300)
Subject: Initial commit
X-Git-Tag: v0.1.0^0
X-Git-Url: http://www.git.cypherpunks.ru/?p=gorecfile.git;a=commitdiff_plain;h=d2a8c845d659ec5b5dbda5e9c5207e7f09269c50

Initial commit
---

d2a8c845d659ec5b5dbda5e9c5207e7f09269c50
diff --git a/README b/README
new file mode 100644
index 0000000..8489c68
--- /dev/null
+++ b/README
@@ -0,0 +1 @@
+GNU recutils'es recfile parser on pure Go.
diff --git a/cmd/gorecsel/main.go b/cmd/gorecsel/main.go
new file mode 100644
index 0000000..13844c6
--- /dev/null
+++ b/cmd/gorecsel/main.go
@@ -0,0 +1,31 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+
+	"go.cypherpunks.ru/recfile"
+)
+
+func main() {
+	r := recfile.NewReader(os.Stdin)
+	n := 0
+	for {
+		fields, err := r.Next()
+		if err != nil {
+			if err == io.EOF {
+				return
+			}
+			panic(err)
+		}
+		if n > 0 {
+			fmt.Println("")
+		}
+		fmt.Println("Record:", n)
+		for _, field := range fields {
+			fmt.Printf("%s: %s\n", field.Name, field.Value)
+		}
+		n++
+	}
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..a605297
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module go.cypherpunks.ru/recfile
+
+go 1.14
diff --git a/r.go b/r.go
new file mode 100644
index 0000000..3614171
--- /dev/null
+++ b/r.go
@@ -0,0 +1,125 @@
+/*
+recfile -- GNU recutils'es recfiles parser on pure Go
+Copyright (C) 2020 Sergey Matveev <stargrave@stargrave.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, version 3 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package recfile
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"regexp"
+	"strings"
+)
+
+type Reader struct {
+	scanner *bufio.Scanner
+}
+
+func NewReader(r io.Reader) *Reader {
+	return &Reader{bufio.NewScanner(r)}
+}
+
+type Field struct {
+	Name  string
+	Value string
+}
+
+var KeyValRe = regexp.MustCompile(`([a-zA-Z%][a-zA-Z0-9_]*):\s*(.*)$`)
+
+func (r *Reader) Next() ([]Field, error) {
+	fields := make([]Field, 0, 1)
+	var text string
+	var name string
+	var line string
+	lines := make([]string, 0)
+	continuation := false
+	var err error
+	for {
+		if !r.scanner.Scan() {
+			if err := r.scanner.Err(); err != nil {
+				return fields, err
+			}
+			err = io.EOF
+			break
+		}
+		text = r.scanner.Text()
+
+		if continuation {
+			if text[len(text)-1] == '\\' {
+				lines = append(lines, text[:len(text)-1])
+			} else {
+				lines = append(lines, text)
+				fields = append(fields, Field{name, strings.Join(lines, "")})
+				lines = make([]string, 0)
+				continuation = false
+			}
+			continue
+		}
+
+		if len(text) > 0 && text[0] == '#' {
+			continue
+		}
+
+		if len(text) > 0 && text[0] == '+' {
+			lines = append(lines, "\n")
+			if len(text) > 1 {
+				if text[1] == ' ' {
+					lines = append(lines, text[2:])
+				} else {
+					lines = append(lines, text[1:])
+				}
+			}
+			continue
+		}
+
+		if len(lines) > 0 {
+			fields = append(fields, Field{name, strings.Join(lines, "")})
+			lines = make([]string, 0)
+		}
+
+		if text == "" {
+			break
+		}
+
+		matches := KeyValRe.FindStringSubmatch(text)
+		if len(matches) == 0 {
+			return fields, errors.New("invalid field format")
+		}
+		name = matches[1]
+		line = matches[2]
+
+		if len(line) > 0 && line[len(line)-1] == '\\' {
+			continuation = true
+			lines = append(lines, line[:len(line)-1])
+		} else {
+			lines = append(lines, line)
+		}
+	}
+	if continuation {
+		return fields, errors.New("left continuation")
+	}
+	if len(lines) > 0 {
+		fields = append(fields, Field{name, strings.Join(lines, "")})
+	}
+	if len(fields) == 0 {
+		if err == nil {
+			return r.Next()
+		}
+		return fields, err
+	}
+	return fields, nil
+}