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-rw-r--r--vendor/github.com/unknwon/com/string.go253
1 files changed, 253 insertions, 0 deletions
diff --git a/vendor/github.com/unknwon/com/string.go b/vendor/github.com/unknwon/com/string.go
new file mode 100644
index 0000000000..7080d174a8
--- /dev/null
+++ b/vendor/github.com/unknwon/com/string.go
@@ -0,0 +1,253 @@
+// Copyright 2013 com authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"): you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations
+// under the License.
+
+package com
+
+import (
+ "bytes"
+ "crypto/aes"
+ "crypto/cipher"
+ "crypto/rand"
+ "errors"
+ r "math/rand"
+ "strconv"
+ "strings"
+ "time"
+ "unicode"
+ "unicode/utf8"
+)
+
+// AESGCMEncrypt encrypts plaintext with the given key using AES in GCM mode.
+func AESGCMEncrypt(key, plaintext []byte) ([]byte, error) {
+ block, err := aes.NewCipher(key)
+ if err != nil {
+ return nil, err
+ }
+
+ gcm, err := cipher.NewGCM(block)
+ if err != nil {
+ return nil, err
+ }
+
+ nonce := make([]byte, gcm.NonceSize())
+ if _, err := rand.Read(nonce); err != nil {
+ return nil, err
+ }
+
+ ciphertext := gcm.Seal(nil, nonce, plaintext, nil)
+ return append(nonce, ciphertext...), nil
+}
+
+// AESGCMDecrypt decrypts ciphertext with the given key using AES in GCM mode.
+func AESGCMDecrypt(key, ciphertext []byte) ([]byte, error) {
+ block, err := aes.NewCipher(key)
+ if err != nil {
+ return nil, err
+ }
+
+ gcm, err := cipher.NewGCM(block)
+ if err != nil {
+ return nil, err
+ }
+
+ size := gcm.NonceSize()
+ if len(ciphertext)-size <= 0 {
+ return nil, errors.New("Ciphertext is empty")
+ }
+
+ nonce := ciphertext[:size]
+ ciphertext = ciphertext[size:]
+
+ plainText, err := gcm.Open(nil, nonce, ciphertext, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ return plainText, nil
+}
+
+// IsLetter returns true if the 'l' is an English letter.
+func IsLetter(l uint8) bool {
+ n := (l | 0x20) - 'a'
+ if n >= 0 && n < 26 {
+ return true
+ }
+ return false
+}
+
+// Expand replaces {k} in template with match[k] or subs[atoi(k)] if k is not in match.
+func Expand(template string, match map[string]string, subs ...string) string {
+ var p []byte
+ var i int
+ for {
+ i = strings.Index(template, "{")
+ if i < 0 {
+ break
+ }
+ p = append(p, template[:i]...)
+ template = template[i+1:]
+ i = strings.Index(template, "}")
+ if s, ok := match[template[:i]]; ok {
+ p = append(p, s...)
+ } else {
+ j, _ := strconv.Atoi(template[:i])
+ if j >= len(subs) {
+ p = append(p, []byte("Missing")...)
+ } else {
+ p = append(p, subs[j]...)
+ }
+ }
+ template = template[i+1:]
+ }
+ p = append(p, template...)
+ return string(p)
+}
+
+// Reverse s string, support unicode
+func Reverse(s string) string {
+ n := len(s)
+ runes := make([]rune, n)
+ for _, rune := range s {
+ n--
+ runes[n] = rune
+ }
+ return string(runes[n:])
+}
+
+// RandomCreateBytes generate random []byte by specify chars.
+func RandomCreateBytes(n int, alphabets ...byte) []byte {
+ const alphanum = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+ var bytes = make([]byte, n)
+ var randby bool
+ if num, err := rand.Read(bytes); num != n || err != nil {
+ r.Seed(time.Now().UnixNano())
+ randby = true
+ }
+ for i, b := range bytes {
+ if len(alphabets) == 0 {
+ if randby {
+ bytes[i] = alphanum[r.Intn(len(alphanum))]
+ } else {
+ bytes[i] = alphanum[b%byte(len(alphanum))]
+ }
+ } else {
+ if randby {
+ bytes[i] = alphabets[r.Intn(len(alphabets))]
+ } else {
+ bytes[i] = alphabets[b%byte(len(alphabets))]
+ }
+ }
+ }
+ return bytes
+}
+
+// ToSnakeCase can convert all upper case characters in a string to
+// underscore format.
+//
+// Some samples.
+// "FirstName" => "first_name"
+// "HTTPServer" => "http_server"
+// "NoHTTPS" => "no_https"
+// "GO_PATH" => "go_path"
+// "GO PATH" => "go_path" // space is converted to underscore.
+// "GO-PATH" => "go_path" // hyphen is converted to underscore.
+//
+// From https://github.com/huandu/xstrings
+func ToSnakeCase(str string) string {
+ if len(str) == 0 {
+ return ""
+ }
+
+ buf := &bytes.Buffer{}
+ var prev, r0, r1 rune
+ var size int
+
+ r0 = '_'
+
+ for len(str) > 0 {
+ prev = r0
+ r0, size = utf8.DecodeRuneInString(str)
+ str = str[size:]
+
+ switch {
+ case r0 == utf8.RuneError:
+ buf.WriteByte(byte(str[0]))
+
+ case unicode.IsUpper(r0):
+ if prev != '_' {
+ buf.WriteRune('_')
+ }
+
+ buf.WriteRune(unicode.ToLower(r0))
+
+ if len(str) == 0 {
+ break
+ }
+
+ r0, size = utf8.DecodeRuneInString(str)
+ str = str[size:]
+
+ if !unicode.IsUpper(r0) {
+ buf.WriteRune(r0)
+ break
+ }
+
+ // find next non-upper-case character and insert `_` properly.
+ // it's designed to convert `HTTPServer` to `http_server`.
+ // if there are more than 2 adjacent upper case characters in a word,
+ // treat them as an abbreviation plus a normal word.
+ for len(str) > 0 {
+ r1 = r0
+ r0, size = utf8.DecodeRuneInString(str)
+ str = str[size:]
+
+ if r0 == utf8.RuneError {
+ buf.WriteRune(unicode.ToLower(r1))
+ buf.WriteByte(byte(str[0]))
+ break
+ }
+
+ if !unicode.IsUpper(r0) {
+ if r0 == '_' || r0 == ' ' || r0 == '-' {
+ r0 = '_'
+
+ buf.WriteRune(unicode.ToLower(r1))
+ } else {
+ buf.WriteRune('_')
+ buf.WriteRune(unicode.ToLower(r1))
+ buf.WriteRune(r0)
+ }
+
+ break
+ }
+
+ buf.WriteRune(unicode.ToLower(r1))
+ }
+
+ if len(str) == 0 || r0 == '_' {
+ buf.WriteRune(unicode.ToLower(r0))
+ break
+ }
+
+ default:
+ if r0 == ' ' || r0 == '-' {
+ r0 = '_'
+ }
+
+ buf.WriteRune(r0)
+ }
+ }
+
+ return buf.String()
+}