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authorRaúl Benencia <raul@thousandeyes.com>2018-04-13 16:30:31 -0700
committerRaúl Benencia <raul@thousandeyes.com>2018-05-11 15:02:34 -0700
commit77c172b823b64ebface655681ab0749b9d2f7081 (patch)
tree09c13e626eb95ae1d33e76ed683172eab1ab6c96 /vendor/github.com/go-logfmt/logfmt/jsonstring.go
First public commit
Diffstat (limited to 'vendor/github.com/go-logfmt/logfmt/jsonstring.go')
-rw-r--r--vendor/github.com/go-logfmt/logfmt/jsonstring.go277
1 files changed, 277 insertions, 0 deletions
diff --git a/vendor/github.com/go-logfmt/logfmt/jsonstring.go b/vendor/github.com/go-logfmt/logfmt/jsonstring.go
new file mode 100644
index 0000000..030ac85
--- /dev/null
+++ b/vendor/github.com/go-logfmt/logfmt/jsonstring.go
@@ -0,0 +1,277 @@
+package logfmt
+
+import (
+ "bytes"
+ "io"
+ "strconv"
+ "sync"
+ "unicode"
+ "unicode/utf16"
+ "unicode/utf8"
+)
+
+// Taken from Go's encoding/json and modified for use here.
+
+// Copyright 2010 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.
+
+var hex = "0123456789abcdef"
+
+var bufferPool = sync.Pool{
+ New: func() interface{} {
+ return &bytes.Buffer{}
+ },
+}
+
+func getBuffer() *bytes.Buffer {
+ return bufferPool.Get().(*bytes.Buffer)
+}
+
+func poolBuffer(buf *bytes.Buffer) {
+ buf.Reset()
+ bufferPool.Put(buf)
+}
+
+// NOTE: keep in sync with writeQuotedBytes below.
+func writeQuotedString(w io.Writer, s string) (int, error) {
+ buf := getBuffer()
+ buf.WriteByte('"')
+ start := 0
+ for i := 0; i < len(s); {
+ if b := s[i]; b < utf8.RuneSelf {
+ if 0x20 <= b && b != '\\' && b != '"' {
+ i++
+ continue
+ }
+ if start < i {
+ buf.WriteString(s[start:i])
+ }
+ switch b {
+ case '\\', '"':
+ buf.WriteByte('\\')
+ buf.WriteByte(b)
+ case '\n':
+ buf.WriteByte('\\')
+ buf.WriteByte('n')
+ case '\r':
+ buf.WriteByte('\\')
+ buf.WriteByte('r')
+ case '\t':
+ buf.WriteByte('\\')
+ buf.WriteByte('t')
+ default:
+ // This encodes bytes < 0x20 except for \n, \r, and \t.
+ buf.WriteString(`\u00`)
+ buf.WriteByte(hex[b>>4])
+ buf.WriteByte(hex[b&0xF])
+ }
+ i++
+ start = i
+ continue
+ }
+ c, size := utf8.DecodeRuneInString(s[i:])
+ if c == utf8.RuneError {
+ if start < i {
+ buf.WriteString(s[start:i])
+ }
+ buf.WriteString(`\ufffd`)
+ i += size
+ start = i
+ continue
+ }
+ i += size
+ }
+ if start < len(s) {
+ buf.WriteString(s[start:])
+ }
+ buf.WriteByte('"')
+ n, err := w.Write(buf.Bytes())
+ poolBuffer(buf)
+ return n, err
+}
+
+// NOTE: keep in sync with writeQuoteString above.
+func writeQuotedBytes(w io.Writer, s []byte) (int, error) {
+ buf := getBuffer()
+ buf.WriteByte('"')
+ start := 0
+ for i := 0; i < len(s); {
+ if b := s[i]; b < utf8.RuneSelf {
+ if 0x20 <= b && b != '\\' && b != '"' {
+ i++
+ continue
+ }
+ if start < i {
+ buf.Write(s[start:i])
+ }
+ switch b {
+ case '\\', '"':
+ buf.WriteByte('\\')
+ buf.WriteByte(b)
+ case '\n':
+ buf.WriteByte('\\')
+ buf.WriteByte('n')
+ case '\r':
+ buf.WriteByte('\\')
+ buf.WriteByte('r')
+ case '\t':
+ buf.WriteByte('\\')
+ buf.WriteByte('t')
+ default:
+ // This encodes bytes < 0x20 except for \n, \r, and \t.
+ buf.WriteString(`\u00`)
+ buf.WriteByte(hex[b>>4])
+ buf.WriteByte(hex[b&0xF])
+ }
+ i++
+ start = i
+ continue
+ }
+ c, size := utf8.DecodeRune(s[i:])
+ if c == utf8.RuneError {
+ if start < i {
+ buf.Write(s[start:i])
+ }
+ buf.WriteString(`\ufffd`)
+ i += size
+ start = i
+ continue
+ }
+ i += size
+ }
+ if start < len(s) {
+ buf.Write(s[start:])
+ }
+ buf.WriteByte('"')
+ n, err := w.Write(buf.Bytes())
+ poolBuffer(buf)
+ return n, err
+}
+
+// getu4 decodes \uXXXX from the beginning of s, returning the hex value,
+// or it returns -1.
+func getu4(s []byte) rune {
+ if len(s) < 6 || s[0] != '\\' || s[1] != 'u' {
+ return -1
+ }
+ r, err := strconv.ParseUint(string(s[2:6]), 16, 64)
+ if err != nil {
+ return -1
+ }
+ return rune(r)
+}
+
+func unquoteBytes(s []byte) (t []byte, ok bool) {
+ if len(s) < 2 || s[0] != '"' || s[len(s)-1] != '"' {
+ return
+ }
+ s = s[1 : len(s)-1]
+
+ // Check for unusual characters. If there are none,
+ // then no unquoting is needed, so return a slice of the
+ // original bytes.
+ r := 0
+ for r < len(s) {
+ c := s[r]
+ if c == '\\' || c == '"' || c < ' ' {
+ break
+ }
+ if c < utf8.RuneSelf {
+ r++
+ continue
+ }
+ rr, size := utf8.DecodeRune(s[r:])
+ if rr == utf8.RuneError {
+ break
+ }
+ r += size
+ }
+ if r == len(s) {
+ return s, true
+ }
+
+ b := make([]byte, len(s)+2*utf8.UTFMax)
+ w := copy(b, s[0:r])
+ for r < len(s) {
+ // Out of room? Can only happen if s is full of
+ // malformed UTF-8 and we're replacing each
+ // byte with RuneError.
+ if w >= len(b)-2*utf8.UTFMax {
+ nb := make([]byte, (len(b)+utf8.UTFMax)*2)
+ copy(nb, b[0:w])
+ b = nb
+ }
+ switch c := s[r]; {
+ case c == '\\':
+ r++
+ if r >= len(s) {
+ return
+ }
+ switch s[r] {
+ default:
+ return
+ case '"', '\\', '/', '\'':
+ b[w] = s[r]
+ r++
+ w++
+ case 'b':
+ b[w] = '\b'
+ r++
+ w++
+ case 'f':
+ b[w] = '\f'
+ r++
+ w++
+ case 'n':
+ b[w] = '\n'
+ r++
+ w++
+ case 'r':
+ b[w] = '\r'
+ r++
+ w++
+ case 't':
+ b[w] = '\t'
+ r++
+ w++
+ case 'u':
+ r--
+ rr := getu4(s[r:])
+ if rr < 0 {
+ return
+ }
+ r += 6
+ if utf16.IsSurrogate(rr) {
+ rr1 := getu4(s[r:])
+ if dec := utf16.DecodeRune(rr, rr1); dec != unicode.ReplacementChar {
+ // A valid pair; consume.
+ r += 6
+ w += utf8.EncodeRune(b[w:], dec)
+ break
+ }
+ // Invalid surrogate; fall back to replacement rune.
+ rr = unicode.ReplacementChar
+ }
+ w += utf8.EncodeRune(b[w:], rr)
+ }
+
+ // Quote, control characters are invalid.
+ case c == '"', c < ' ':
+ return
+
+ // ASCII
+ case c < utf8.RuneSelf:
+ b[w] = c
+ r++
+ w++
+
+ // Coerce to well-formed UTF-8.
+ default:
+ rr, size := utf8.DecodeRune(s[r:])
+ r += size
+ w += utf8.EncodeRune(b[w:], rr)
+ }
+ }
+ return b[0:w], true
+}
nihil fit ex nihilo