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-rw-r--r--vendor/github.com/rs/zerolog/internal/json/string.go149
1 files changed, 149 insertions, 0 deletions
diff --git a/vendor/github.com/rs/zerolog/internal/json/string.go b/vendor/github.com/rs/zerolog/internal/json/string.go
new file mode 100644
index 00000000..fd7770f2
--- /dev/null
+++ b/vendor/github.com/rs/zerolog/internal/json/string.go
@@ -0,0 +1,149 @@
+package json
+
+import (
+ "fmt"
+ "unicode/utf8"
+)
+
+const hex = "0123456789abcdef"
+
+var noEscapeTable = [256]bool{}
+
+func init() {
+ for i := 0; i <= 0x7e; i++ {
+ noEscapeTable[i] = i >= 0x20 && i != '\\' && i != '"'
+ }
+}
+
+// AppendStrings encodes the input strings to json and
+// appends the encoded string list to the input byte slice.
+func (e Encoder) AppendStrings(dst []byte, vals []string) []byte {
+ if len(vals) == 0 {
+ return append(dst, '[', ']')
+ }
+ dst = append(dst, '[')
+ dst = e.AppendString(dst, vals[0])
+ if len(vals) > 1 {
+ for _, val := range vals[1:] {
+ dst = e.AppendString(append(dst, ','), val)
+ }
+ }
+ dst = append(dst, ']')
+ return dst
+}
+
+// AppendString encodes the input string to json and appends
+// the encoded string to the input byte slice.
+//
+// The operation loops though each byte in the string looking
+// for characters that need json or utf8 encoding. If the string
+// does not need encoding, then the string is appended in its
+// entirety to the byte slice.
+// If we encounter a byte that does need encoding, switch up
+// the operation and perform a byte-by-byte read-encode-append.
+func (Encoder) AppendString(dst []byte, s string) []byte {
+ // Start with a double quote.
+ dst = append(dst, '"')
+ // Loop through each character in the string.
+ for i := 0; i < len(s); i++ {
+ // Check if the character needs encoding. Control characters, slashes,
+ // and the double quote need json encoding. Bytes above the ascii
+ // boundary needs utf8 encoding.
+ if !noEscapeTable[s[i]] {
+ // We encountered a character that needs to be encoded. Switch
+ // to complex version of the algorithm.
+ dst = appendStringComplex(dst, s, i)
+ return append(dst, '"')
+ }
+ }
+ // The string has no need for encoding and therefore is directly
+ // appended to the byte slice.
+ dst = append(dst, s...)
+ // End with a double quote
+ return append(dst, '"')
+}
+
+// AppendStringers encodes the provided Stringer list to json and
+// appends the encoded Stringer list to the input byte slice.
+func (e Encoder) AppendStringers(dst []byte, vals []fmt.Stringer) []byte {
+ if len(vals) == 0 {
+ return append(dst, '[', ']')
+ }
+ dst = append(dst, '[')
+ dst = e.AppendStringer(dst, vals[0])
+ if len(vals) > 1 {
+ for _, val := range vals[1:] {
+ dst = e.AppendStringer(append(dst, ','), val)
+ }
+ }
+ return append(dst, ']')
+}
+
+// AppendStringer encodes the input Stringer to json and appends the
+// encoded Stringer value to the input byte slice.
+func (e Encoder) AppendStringer(dst []byte, val fmt.Stringer) []byte {
+ if val == nil {
+ return e.AppendInterface(dst, nil)
+ }
+ return e.AppendString(dst, val.String())
+}
+
+//// appendStringComplex is used by appendString to take over an in
+// progress JSON string encoding that encountered a character that needs
+// to be encoded.
+func appendStringComplex(dst []byte, s string, i int) []byte {
+ start := 0
+ for i < len(s) {
+ b := s[i]
+ if b >= utf8.RuneSelf {
+ r, size := utf8.DecodeRuneInString(s[i:])
+ if r == utf8.RuneError && size == 1 {
+ // In case of error, first append previous simple characters to
+ // the byte slice if any and append a replacement character code
+ // in place of the invalid sequence.
+ if start < i {
+ dst = append(dst, s[start:i]...)
+ }
+ dst = append(dst, `\ufffd`...)
+ i += size
+ start = i
+ continue
+ }
+ i += size
+ continue
+ }
+ if noEscapeTable[b] {
+ i++
+ continue
+ }
+ // We encountered a character that needs to be encoded.
+ // Let's append the previous simple characters to the byte slice
+ // and switch our operation to read and encode the remainder
+ // characters byte-by-byte.
+ if start < i {
+ dst = append(dst, s[start:i]...)
+ }
+ switch b {
+ case '"', '\\':
+ dst = append(dst, '\\', b)
+ case '\b':
+ dst = append(dst, '\\', 'b')
+ case '\f':
+ dst = append(dst, '\\', 'f')
+ case '\n':
+ dst = append(dst, '\\', 'n')
+ case '\r':
+ dst = append(dst, '\\', 'r')
+ case '\t':
+ dst = append(dst, '\\', 't')
+ default:
+ dst = append(dst, '\\', 'u', '0', '0', hex[b>>4], hex[b&0xF])
+ }
+ i++
+ start = i
+ }
+ if start < len(s) {
+ dst = append(dst, s[start:]...)
+ }
+ return dst
+}