gtsocial-umbx

quote.go (2331B)

---

 package shellquote
 
 import (
 	"bytes"
 	"strings"
 	"unicode/utf8"
 )
 
 // Join quotes each argument and joins them with a space.
 // If passed to /bin/sh, the resulting string will be split back into the
 // original arguments.
 func Join(args ...string) string {
 	var buf bytes.Buffer
 	for i, arg := range args {
 		if i != 0 {
 			buf.WriteByte(' ')
 		}
 		quote(arg, &buf)
 	}
 	return buf.String()
 }
 
 const (
 	specialChars      = "\\'\"`${[|&;<>()*?!"
 	extraSpecialChars = " \t\n"
 	prefixChars       = "~"
 )
 
 func quote(word string, buf *bytes.Buffer) {
 	// We want to try to produce a "nice" output. As such, we will
 	// backslash-escape most characters, but if we encounter a space, or if we
 	// encounter an extra-special char (which doesn't work with
 	// backslash-escaping) we switch over to quoting the whole word. We do this
 	// with a space because it's typically easier for people to read multi-word
 	// arguments when quoted with a space rather than with ugly backslashes
 	// everywhere.
 	origLen := buf.Len()
 
 	if len(word) == 0 {
 		// oops, no content
 		buf.WriteString("''")
 		return
 	}
 
 	cur, prev := word, word
 	atStart := true
 	for len(cur) > 0 {
 		c, l := utf8.DecodeRuneInString(cur)
 		cur = cur[l:]
 		if strings.ContainsRune(specialChars, c) || (atStart && strings.ContainsRune(prefixChars, c)) {
 			// copy the non-special chars up to this point
 			if len(cur) < len(prev) {
 				buf.WriteString(prev[0 : len(prev)-len(cur)-l])
 			}
 			buf.WriteByte('\\')
 			buf.WriteRune(c)
 			prev = cur
 		} else if strings.ContainsRune(extraSpecialChars, c) {
 			// start over in quote mode
 			buf.Truncate(origLen)
 			goto quote
 		}
 		atStart = false
 	}
 	if len(prev) > 0 {
 		buf.WriteString(prev)
 	}
 	return
 
 quote:
 	// quote mode
 	// Use single-quotes, but if we find a single-quote in the word, we need
 	// to terminate the string, emit an escaped quote, and start the string up
 	// again
 	inQuote := false
 	for len(word) > 0 {
 		i := strings.IndexRune(word, '\'')
 		if i == -1 {
 			break
 		}
 		if i > 0 {
 			if !inQuote {
 				buf.WriteByte('\'')
 				inQuote = true
 			}
 			buf.WriteString(word[0:i])
 		}
 		word = word[i+1:]
 		if inQuote {
 			buf.WriteByte('\'')
 			inQuote = false
 		}
 		buf.WriteString("\\'")
 	}
 	if len(word) > 0 {
 		if !inQuote {
 			buf.WriteByte('\'')
 		}
 		buf.WriteString(word)
 		buf.WriteByte('\'')
 	}
 }