mirror of
https://github.com/aptly-dev/aptly.git
synced 2026-05-06 22:18:28 +00:00
Andrey Smirnov
82 lines
2.0 KiB
Go
82 lines
2.0 KiB
Go
// Copyright (c) 2011 Mikkel Krautz
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// The use of this source code is goverened by a BSD-style
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// license that can be found in the LICENSE-file.
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// Package ar implements reading and writing of ar archives.
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// It supports reading archives in the GNU and BSD formats, but
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// only supports writing in the BSD format.
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package ar
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import "errors"
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// A Header represents a single file header in an ar archive.
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type Header struct {
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Name string
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Mode int64
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Uid int
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Gid int
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Size int64
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Mtime int64
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}
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var (
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globalHeader = "!<arch>\n"
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bsdLongFileNamePrefix = "#1/"
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fileHeaderMagic = "`\n"
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)
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var (
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ErrMissingGlobalHeader = errors.New("ar: missing global header")
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ErrFileHeader = errors.New("ar: invalid ar file header")
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ErrWriteAfterClose = errors.New("ar: write after close")
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ErrWriteTooLong = errors.New("ar: write too long")
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)
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type skippingWriter struct{}
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func (sw skippingWriter) Write(buf []byte) (int, error) {
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return len(buf), nil
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}
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// nulTerminated returns a nul terminated string read from buf.
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func nulTerminated(buf []byte) string {
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for i := 0; i < len(buf); i++ {
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if buf[i] == 0 {
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return string(buf[0:i])
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}
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}
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return string(buf)
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}
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// gnuArString reads a linefeed terminated string from buf.
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// If a linefeed character is not found in buf, the function
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// returns an error.
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func gnuArString(buf []byte) (string, error) {
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for i := 0; i < len(buf); i++ {
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if buf[i] == '\n' {
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return string(buf[:i]), nil
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}
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}
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return "", errors.New("ar: missing linefeed in parsing ar string")
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}
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// arString reads a whitespace terminated string from the string in.
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func arString(in string) string {
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for i, rune := range in {
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if rune == ' ' || rune == '\t' {
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return in[:i]
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}
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}
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return in
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}
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// Encode a string to the whitespace-padded format used in the ar header.
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func encodeArString(in string, total int) string {
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remain := total - len(in)
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var spaces []byte
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for i := 0; i < remain; i++ {
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spaces = append(spaces, ' ')
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}
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return in + string(spaces)
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}
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