diff options
Diffstat (limited to 'vendor/github.com/kballard/go-shellquote/unquote.go')
-rw-r--r-- | vendor/github.com/kballard/go-shellquote/unquote.go | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/vendor/github.com/kballard/go-shellquote/unquote.go b/vendor/github.com/kballard/go-shellquote/unquote.go new file mode 100644 index 00000000..b1b13da9 --- /dev/null +++ b/vendor/github.com/kballard/go-shellquote/unquote.go @@ -0,0 +1,156 @@ +package shellquote + +import ( + "bytes" + "errors" + "strings" + "unicode/utf8" +) + +var ( + UnterminatedSingleQuoteError = errors.New("Unterminated single-quoted string") + UnterminatedDoubleQuoteError = errors.New("Unterminated double-quoted string") + UnterminatedEscapeError = errors.New("Unterminated backslash-escape") +) + +var ( + splitChars = " \n\t" + singleChar = '\'' + doubleChar = '"' + escapeChar = '\\' + doubleEscapeChars = "$`\"\n\\" +) + +// Split splits a string according to /bin/sh's word-splitting rules. It +// supports backslash-escapes, single-quotes, and double-quotes. Notably it does +// not support the $'' style of quoting. It also doesn't attempt to perform any +// other sort of expansion, including brace expansion, shell expansion, or +// pathname expansion. +// +// If the given input has an unterminated quoted string or ends in a +// backslash-escape, one of UnterminatedSingleQuoteError, +// UnterminatedDoubleQuoteError, or UnterminatedEscapeError is returned. +func Split(input string) (words []string, err error) { + var buf bytes.Buffer + words = make([]string, 0) + + for len(input) > 0 { + // skip any splitChars at the start + c, l := utf8.DecodeRuneInString(input) + if strings.ContainsRune(splitChars, c) { + input = input[l:] + continue + } else if c == escapeChar { + // Look ahead for escaped newline so we can skip over it + next := input[l:] + if len(next) == 0 { + err = UnterminatedEscapeError + return + } + c2, l2 := utf8.DecodeRuneInString(next) + if c2 == '\n' { + input = next[l2:] + continue + } + } + + var word string + word, input, err = splitWord(input, &buf) + if err != nil { + return + } + words = append(words, word) + } + return +} + +func splitWord(input string, buf *bytes.Buffer) (word string, remainder string, err error) { + buf.Reset() + +raw: + { + cur := input + for len(cur) > 0 { + c, l := utf8.DecodeRuneInString(cur) + cur = cur[l:] + if c == singleChar { + buf.WriteString(input[0 : len(input)-len(cur)-l]) + input = cur + goto single + } else if c == doubleChar { + buf.WriteString(input[0 : len(input)-len(cur)-l]) + input = cur + goto double + } else if c == escapeChar { + buf.WriteString(input[0 : len(input)-len(cur)-l]) + input = cur + goto escape + } else if strings.ContainsRune(splitChars, c) { + buf.WriteString(input[0 : len(input)-len(cur)-l]) + return buf.String(), cur, nil + } + } + if len(input) > 0 { + buf.WriteString(input) + input = "" + } + goto done + } + +escape: + { + if len(input) == 0 { + return "", "", UnterminatedEscapeError + } + c, l := utf8.DecodeRuneInString(input) + if c == '\n' { + // a backslash-escaped newline is elided from the output entirely + } else { + buf.WriteString(input[:l]) + } + input = input[l:] + } + goto raw + +single: + { + i := strings.IndexRune(input, singleChar) + if i == -1 { + return "", "", UnterminatedSingleQuoteError + } + buf.WriteString(input[0:i]) + input = input[i+1:] + goto raw + } + +double: + { + cur := input + for len(cur) > 0 { + c, l := utf8.DecodeRuneInString(cur) + cur = cur[l:] + if c == doubleChar { + buf.WriteString(input[0 : len(input)-len(cur)-l]) + input = cur + goto raw + } else if c == escapeChar { + // bash only supports certain escapes in double-quoted strings + c2, l2 := utf8.DecodeRuneInString(cur) + cur = cur[l2:] + if strings.ContainsRune(doubleEscapeChars, c2) { + buf.WriteString(input[0 : len(input)-len(cur)-l-l2]) + if c2 == '\n' { + // newline is special, skip the backslash entirely + } else { + buf.WriteRune(c2) + } + input = cur + } + } + } + return "", "", UnterminatedDoubleQuoteError + } + +done: + return buf.String(), input, nil +} |