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-rw-r--r--vendor/gopkg.in/gcfg.v1/scanner/errors.go121
-rw-r--r--vendor/gopkg.in/gcfg.v1/scanner/scanner.go342
2 files changed, 463 insertions, 0 deletions
diff --git a/vendor/gopkg.in/gcfg.v1/scanner/errors.go b/vendor/gopkg.in/gcfg.v1/scanner/errors.go
new file mode 100644
index 00000000..1a3c0f65
--- /dev/null
+++ b/vendor/gopkg.in/gcfg.v1/scanner/errors.go
@@ -0,0 +1,121 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package scanner
+
+import (
+ "fmt"
+ "io"
+ "sort"
+)
+
+import (
+ "gopkg.in/gcfg.v1/token"
+)
+
+// In an ErrorList, an error is represented by an *Error.
+// The position Pos, if valid, points to the beginning of
+// the offending token, and the error condition is described
+// by Msg.
+//
+type Error struct {
+ Pos token.Position
+ Msg string
+}
+
+// Error implements the error interface.
+func (e Error) Error() string {
+ if e.Pos.Filename != "" || e.Pos.IsValid() {
+ // don't print "<unknown position>"
+ // TODO(gri) reconsider the semantics of Position.IsValid
+ return e.Pos.String() + ": " + e.Msg
+ }
+ return e.Msg
+}
+
+// ErrorList is a list of *Errors.
+// The zero value for an ErrorList is an empty ErrorList ready to use.
+//
+type ErrorList []*Error
+
+// Add adds an Error with given position and error message to an ErrorList.
+func (p *ErrorList) Add(pos token.Position, msg string) {
+ *p = append(*p, &Error{pos, msg})
+}
+
+// Reset resets an ErrorList to no errors.
+func (p *ErrorList) Reset() { *p = (*p)[0:0] }
+
+// ErrorList implements the sort Interface.
+func (p ErrorList) Len() int { return len(p) }
+func (p ErrorList) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
+
+func (p ErrorList) Less(i, j int) bool {
+ e := &p[i].Pos
+ f := &p[j].Pos
+ if e.Filename < f.Filename {
+ return true
+ }
+ if e.Filename == f.Filename {
+ return e.Offset < f.Offset
+ }
+ return false
+}
+
+// Sort sorts an ErrorList. *Error entries are sorted by position,
+// other errors are sorted by error message, and before any *Error
+// entry.
+//
+func (p ErrorList) Sort() {
+ sort.Sort(p)
+}
+
+// RemoveMultiples sorts an ErrorList and removes all but the first error per line.
+func (p *ErrorList) RemoveMultiples() {
+ sort.Sort(p)
+ var last token.Position // initial last.Line is != any legal error line
+ i := 0
+ for _, e := range *p {
+ if e.Pos.Filename != last.Filename || e.Pos.Line != last.Line {
+ last = e.Pos
+ (*p)[i] = e
+ i++
+ }
+ }
+ (*p) = (*p)[0:i]
+}
+
+// An ErrorList implements the error interface.
+func (p ErrorList) Error() string {
+ switch len(p) {
+ case 0:
+ return "no errors"
+ case 1:
+ return p[0].Error()
+ }
+ return fmt.Sprintf("%s (and %d more errors)", p[0], len(p)-1)
+}
+
+// Err returns an error equivalent to this error list.
+// If the list is empty, Err returns nil.
+func (p ErrorList) Err() error {
+ if len(p) == 0 {
+ return nil
+ }
+ return p
+}
+
+// PrintError is a utility function that prints a list of errors to w,
+// one error per line, if the err parameter is an ErrorList. Otherwise
+// it prints the err string.
+//
+func PrintError(w io.Writer, err error) {
+ if list, ok := err.(ErrorList); ok {
+ for _, e := range list {
+ fmt.Fprintf(w, "%s\n", e)
+ }
+ } else if err != nil {
+ fmt.Fprintf(w, "%s\n", err)
+ }
+}
diff --git a/vendor/gopkg.in/gcfg.v1/scanner/scanner.go b/vendor/gopkg.in/gcfg.v1/scanner/scanner.go
new file mode 100644
index 00000000..bbbdbf53
--- /dev/null
+++ b/vendor/gopkg.in/gcfg.v1/scanner/scanner.go
@@ -0,0 +1,342 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package scanner implements a scanner for gcfg configuration text.
+// It takes a []byte as source which can then be tokenized
+// through repeated calls to the Scan method.
+//
+// Note that the API for the scanner package may change to accommodate new
+// features or implementation changes in gcfg.
+//
+package scanner
+
+import (
+ "fmt"
+ "path/filepath"
+ "unicode"
+ "unicode/utf8"
+)
+
+import (
+ "gopkg.in/gcfg.v1/token"
+)
+
+// An ErrorHandler may be provided to Scanner.Init. If a syntax error is
+// encountered and a handler was installed, the handler is called with a
+// position and an error message. The position points to the beginning of
+// the offending token.
+//
+type ErrorHandler func(pos token.Position, msg string)
+
+// A Scanner holds the scanner's internal state while processing
+// a given text. It can be allocated as part of another data
+// structure but must be initialized via Init before use.
+//
+type Scanner struct {
+ // immutable state
+ file *token.File // source file handle
+ dir string // directory portion of file.Name()
+ src []byte // source
+ err ErrorHandler // error reporting; or nil
+ mode Mode // scanning mode
+
+ // scanning state
+ ch rune // current character
+ offset int // character offset
+ rdOffset int // reading offset (position after current character)
+ lineOffset int // current line offset
+ nextVal bool // next token is expected to be a value
+
+ // public state - ok to modify
+ ErrorCount int // number of errors encountered
+}
+
+// Read the next Unicode char into s.ch.
+// s.ch < 0 means end-of-file.
+//
+func (s *Scanner) next() {
+ if s.rdOffset < len(s.src) {
+ s.offset = s.rdOffset
+ if s.ch == '\n' {
+ s.lineOffset = s.offset
+ s.file.AddLine(s.offset)
+ }
+ r, w := rune(s.src[s.rdOffset]), 1
+ switch {
+ case r == 0:
+ s.error(s.offset, "illegal character NUL")
+ case r >= 0x80:
+ // not ASCII
+ r, w = utf8.DecodeRune(s.src[s.rdOffset:])
+ if r == utf8.RuneError && w == 1 {
+ s.error(s.offset, "illegal UTF-8 encoding")
+ }
+ }
+ s.rdOffset += w
+ s.ch = r
+ } else {
+ s.offset = len(s.src)
+ if s.ch == '\n' {
+ s.lineOffset = s.offset
+ s.file.AddLine(s.offset)
+ }
+ s.ch = -1 // eof
+ }
+}
+
+// A mode value is a set of flags (or 0).
+// They control scanner behavior.
+//
+type Mode uint
+
+const (
+ ScanComments Mode = 1 << iota // return comments as COMMENT tokens
+)
+
+// Init prepares the scanner s to tokenize the text src by setting the
+// scanner at the beginning of src. The scanner uses the file set file
+// for position information and it adds line information for each line.
+// It is ok to re-use the same file when re-scanning the same file as
+// line information which is already present is ignored. Init causes a
+// panic if the file size does not match the src size.
+//
+// Calls to Scan will invoke the error handler err if they encounter a
+// syntax error and err is not nil. Also, for each error encountered,
+// the Scanner field ErrorCount is incremented by one. The mode parameter
+// determines how comments are handled.
+//
+// Note that Init may call err if there is an error in the first character
+// of the file.
+//
+func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
+ // Explicitly initialize all fields since a scanner may be reused.
+ if file.Size() != len(src) {
+ panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
+ }
+ s.file = file
+ s.dir, _ = filepath.Split(file.Name())
+ s.src = src
+ s.err = err
+ s.mode = mode
+
+ s.ch = ' '
+ s.offset = 0
+ s.rdOffset = 0
+ s.lineOffset = 0
+ s.ErrorCount = 0
+ s.nextVal = false
+
+ s.next()
+}
+
+func (s *Scanner) error(offs int, msg string) {
+ if s.err != nil {
+ s.err(s.file.Position(s.file.Pos(offs)), msg)
+ }
+ s.ErrorCount++
+}
+
+func (s *Scanner) scanComment() string {
+ // initial [;#] already consumed
+ offs := s.offset - 1 // position of initial [;#]
+
+ for s.ch != '\n' && s.ch >= 0 {
+ s.next()
+ }
+ return string(s.src[offs:s.offset])
+}
+
+func isLetter(ch rune) bool {
+ return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch >= 0x80 && unicode.IsLetter(ch)
+}
+
+func isDigit(ch rune) bool {
+ return '0' <= ch && ch <= '9' || ch >= 0x80 && unicode.IsDigit(ch)
+}
+
+func (s *Scanner) scanIdentifier() string {
+ offs := s.offset
+ for isLetter(s.ch) || isDigit(s.ch) || s.ch == '-' {
+ s.next()
+ }
+ return string(s.src[offs:s.offset])
+}
+
+func (s *Scanner) scanEscape(val bool) {
+ offs := s.offset
+ ch := s.ch
+ s.next() // always make progress
+ switch ch {
+ case '\\', '"':
+ // ok
+ case 'n', 't':
+ if val {
+ break // ok
+ }
+ fallthrough
+ default:
+ s.error(offs, "unknown escape sequence")
+ }
+}
+
+func (s *Scanner) scanString() string {
+ // '"' opening already consumed
+ offs := s.offset - 1
+
+ for s.ch != '"' {
+ ch := s.ch
+ s.next()
+ if ch == '\n' || ch < 0 {
+ s.error(offs, "string not terminated")
+ break
+ }
+ if ch == '\\' {
+ s.scanEscape(false)
+ }
+ }
+
+ s.next()
+
+ return string(s.src[offs:s.offset])
+}
+
+func stripCR(b []byte) []byte {
+ c := make([]byte, len(b))
+ i := 0
+ for _, ch := range b {
+ if ch != '\r' {
+ c[i] = ch
+ i++
+ }
+ }
+ return c[:i]
+}
+
+func (s *Scanner) scanValString() string {
+ offs := s.offset
+
+ hasCR := false
+ end := offs
+ inQuote := false
+loop:
+ for inQuote || s.ch >= 0 && s.ch != '\n' && s.ch != ';' && s.ch != '#' {
+ ch := s.ch
+ s.next()
+ switch {
+ case inQuote && ch == '\\':
+ s.scanEscape(true)
+ case !inQuote && ch == '\\':
+ if s.ch == '\r' {
+ hasCR = true
+ s.next()
+ }
+ if s.ch != '\n' {
+ s.error(offs, "unquoted '\\' must be followed by new line")
+ break loop
+ }
+ s.next()
+ case ch == '"':
+ inQuote = !inQuote
+ case ch == '\r':
+ hasCR = true
+ case ch < 0 || inQuote && ch == '\n':
+ s.error(offs, "string not terminated")
+ break loop
+ }
+ if inQuote || !isWhiteSpace(ch) {
+ end = s.offset
+ }
+ }
+
+ lit := s.src[offs:end]
+ if hasCR {
+ lit = stripCR(lit)
+ }
+
+ return string(lit)
+}
+
+func isWhiteSpace(ch rune) bool {
+ return ch == ' ' || ch == '\t' || ch == '\r'
+}
+
+func (s *Scanner) skipWhitespace() {
+ for isWhiteSpace(s.ch) {
+ s.next()
+ }
+}
+
+// Scan scans the next token and returns the token position, the token,
+// and its literal string if applicable. The source end is indicated by
+// token.EOF.
+//
+// If the returned token is a literal (token.IDENT, token.STRING) or
+// token.COMMENT, the literal string has the corresponding value.
+//
+// If the returned token is token.ILLEGAL, the literal string is the
+// offending character.
+//
+// In all other cases, Scan returns an empty literal string.
+//
+// For more tolerant parsing, Scan will return a valid token if
+// possible even if a syntax error was encountered. Thus, even
+// if the resulting token sequence contains no illegal tokens,
+// a client may not assume that no error occurred. Instead it
+// must check the scanner's ErrorCount or the number of calls
+// of the error handler, if there was one installed.
+//
+// Scan adds line information to the file added to the file
+// set with Init. Token positions are relative to that file
+// and thus relative to the file set.
+//
+func (s *Scanner) Scan() (pos token.Pos, tok token.Token, lit string) {
+scanAgain:
+ s.skipWhitespace()
+
+ // current token start
+ pos = s.file.Pos(s.offset)
+
+ // determine token value
+ switch ch := s.ch; {
+ case s.nextVal:
+ lit = s.scanValString()
+ tok = token.STRING
+ s.nextVal = false
+ case isLetter(ch):
+ lit = s.scanIdentifier()
+ tok = token.IDENT
+ default:
+ s.next() // always make progress
+ switch ch {
+ case -1:
+ tok = token.EOF
+ case '\n':
+ tok = token.EOL
+ case '"':
+ tok = token.STRING
+ lit = s.scanString()
+ case '[':
+ tok = token.LBRACK
+ case ']':
+ tok = token.RBRACK
+ case ';', '#':
+ // comment
+ lit = s.scanComment()
+ if s.mode&ScanComments == 0 {
+ // skip comment
+ goto scanAgain
+ }
+ tok = token.COMMENT
+ case '=':
+ tok = token.ASSIGN
+ s.nextVal = true
+ default:
+ s.error(s.file.Offset(pos), fmt.Sprintf("illegal character %#U", ch))
+ tok = token.ILLEGAL
+ lit = string(ch)
+ }
+ }
+
+ return
+}