rclone/vendor/github.com/json-iterator/go/stream_str.go

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2020-06-27 16:45:12 +02:00
package jsoniter
import (
"unicode/utf8"
)
// htmlSafeSet holds the value true if the ASCII character with the given
// array position can be safely represented inside a JSON string, embedded
// inside of HTML <script> tags, without any additional escaping.
//
// All values are true except for the ASCII control characters (0-31), the
// double quote ("), the backslash character ("\"), HTML opening and closing
// tags ("<" and ">"), and the ampersand ("&").
var htmlSafeSet = [utf8.RuneSelf]bool{
' ': true,
'!': true,
'"': false,
'#': true,
'$': true,
'%': true,
'&': false,
'\'': true,
'(': true,
')': true,
'*': true,
'+': true,
',': true,
'-': true,
'.': true,
'/': true,
'0': true,
'1': true,
'2': true,
'3': true,
'4': true,
'5': true,
'6': true,
'7': true,
'8': true,
'9': true,
':': true,
';': true,
'<': false,
'=': true,
'>': false,
'?': true,
'@': true,
'A': true,
'B': true,
'C': true,
'D': true,
'E': true,
'F': true,
'G': true,
'H': true,
'I': true,
'J': true,
'K': true,
'L': true,
'M': true,
'N': true,
'O': true,
'P': true,
'Q': true,
'R': true,
'S': true,
'T': true,
'U': true,
'V': true,
'W': true,
'X': true,
'Y': true,
'Z': true,
'[': true,
'\\': false,
']': true,
'^': true,
'_': true,
'`': true,
'a': true,
'b': true,
'c': true,
'd': true,
'e': true,
'f': true,
'g': true,
'h': true,
'i': true,
'j': true,
'k': true,
'l': true,
'm': true,
'n': true,
'o': true,
'p': true,
'q': true,
'r': true,
's': true,
't': true,
'u': true,
'v': true,
'w': true,
'x': true,
'y': true,
'z': true,
'{': true,
'|': true,
'}': true,
'~': true,
'\u007f': true,
}
// safeSet holds the value true if the ASCII character with the given array
// position can be represented inside a JSON string without any further
// escaping.
//
// All values are true except for the ASCII control characters (0-31), the
// double quote ("), and the backslash character ("\").
var safeSet = [utf8.RuneSelf]bool{
' ': true,
'!': true,
'"': false,
'#': true,
'$': true,
'%': true,
'&': true,
'\'': true,
'(': true,
')': true,
'*': true,
'+': true,
',': true,
'-': true,
'.': true,
'/': true,
'0': true,
'1': true,
'2': true,
'3': true,
'4': true,
'5': true,
'6': true,
'7': true,
'8': true,
'9': true,
':': true,
';': true,
'<': true,
'=': true,
'>': true,
'?': true,
'@': true,
'A': true,
'B': true,
'C': true,
'D': true,
'E': true,
'F': true,
'G': true,
'H': true,
'I': true,
'J': true,
'K': true,
'L': true,
'M': true,
'N': true,
'O': true,
'P': true,
'Q': true,
'R': true,
'S': true,
'T': true,
'U': true,
'V': true,
'W': true,
'X': true,
'Y': true,
'Z': true,
'[': true,
'\\': false,
']': true,
'^': true,
'_': true,
'`': true,
'a': true,
'b': true,
'c': true,
'd': true,
'e': true,
'f': true,
'g': true,
'h': true,
'i': true,
'j': true,
'k': true,
'l': true,
'm': true,
'n': true,
'o': true,
'p': true,
'q': true,
'r': true,
's': true,
't': true,
'u': true,
'v': true,
'w': true,
'x': true,
'y': true,
'z': true,
'{': true,
'|': true,
'}': true,
'~': true,
'\u007f': true,
}
var hex = "0123456789abcdef"
// WriteStringWithHTMLEscaped write string to stream with html special characters escaped
func (stream *Stream) WriteStringWithHTMLEscaped(s string) {
valLen := len(s)
stream.buf = append(stream.buf, '"')
// write string, the fast path, without utf8 and escape support
i := 0
for ; i < valLen; i++ {
c := s[i]
if c < utf8.RuneSelf && htmlSafeSet[c] {
stream.buf = append(stream.buf, c)
} else {
break
}
}
if i == valLen {
stream.buf = append(stream.buf, '"')
return
}
writeStringSlowPathWithHTMLEscaped(stream, i, s, valLen)
}
func writeStringSlowPathWithHTMLEscaped(stream *Stream, i int, s string, valLen int) {
start := i
// for the remaining parts, we process them char by char
for i < valLen {
if b := s[i]; b < utf8.RuneSelf {
if htmlSafeSet[b] {
i++
continue
}
if start < i {
stream.WriteRaw(s[start:i])
}
switch b {
case '\\', '"':
stream.writeTwoBytes('\\', b)
case '\n':
stream.writeTwoBytes('\\', 'n')
case '\r':
stream.writeTwoBytes('\\', 'r')
case '\t':
stream.writeTwoBytes('\\', 't')
default:
// This encodes bytes < 0x20 except for \t, \n and \r.
// If escapeHTML is set, it also escapes <, >, and &
// because they can lead to security holes when
// user-controlled strings are rendered into JSON
// and served to some browsers.
stream.WriteRaw(`\u00`)
stream.writeTwoBytes(hex[b>>4], hex[b&0xF])
}
i++
start = i
continue
}
c, size := utf8.DecodeRuneInString(s[i:])
if c == utf8.RuneError && size == 1 {
if start < i {
stream.WriteRaw(s[start:i])
}
stream.WriteRaw(`\ufffd`)
i++
start = i
continue
}
// U+2028 is LINE SEPARATOR.
// U+2029 is PARAGRAPH SEPARATOR.
// They are both technically valid characters in JSON strings,
// but don't work in JSONP, which has to be evaluated as JavaScript,
// and can lead to security holes there. It is valid JSON to
// escape them, so we do so unconditionally.
// See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
if c == '\u2028' || c == '\u2029' {
if start < i {
stream.WriteRaw(s[start:i])
}
stream.WriteRaw(`\u202`)
stream.writeByte(hex[c&0xF])
i += size
start = i
continue
}
i += size
}
if start < len(s) {
stream.WriteRaw(s[start:])
}
stream.writeByte('"')
}
// WriteString write string to stream without html escape
func (stream *Stream) WriteString(s string) {
valLen := len(s)
stream.buf = append(stream.buf, '"')
// write string, the fast path, without utf8 and escape support
i := 0
for ; i < valLen; i++ {
c := s[i]
if c > 31 && c != '"' && c != '\\' {
stream.buf = append(stream.buf, c)
} else {
break
}
}
if i == valLen {
stream.buf = append(stream.buf, '"')
return
}
writeStringSlowPath(stream, i, s, valLen)
}
func writeStringSlowPath(stream *Stream, i int, s string, valLen int) {
start := i
// for the remaining parts, we process them char by char
for i < valLen {
if b := s[i]; b < utf8.RuneSelf {
if safeSet[b] {
i++
continue
}
if start < i {
stream.WriteRaw(s[start:i])
}
switch b {
case '\\', '"':
stream.writeTwoBytes('\\', b)
case '\n':
stream.writeTwoBytes('\\', 'n')
case '\r':
stream.writeTwoBytes('\\', 'r')
case '\t':
stream.writeTwoBytes('\\', 't')
default:
// This encodes bytes < 0x20 except for \t, \n and \r.
// If escapeHTML is set, it also escapes <, >, and &
// because they can lead to security holes when
// user-controlled strings are rendered into JSON
// and served to some browsers.
stream.WriteRaw(`\u00`)
stream.writeTwoBytes(hex[b>>4], hex[b&0xF])
}
i++
start = i
continue
}
i++
continue
}
if start < len(s) {
stream.WriteRaw(s[start:])
}
stream.writeByte('"')
}