Godeps

Godeps/_workspace/src/gopkg.in/gcfg.v1/read.go

@@ -0,0 +1,188 @@
+package gcfg
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+)
+
+import (
+	"gopkg.in/gcfg.v1/scanner"
+	"gopkg.in/gcfg.v1/token"
+)
+
+var unescape = map[rune]rune{'\\': '\\', '"': '"', 'n': '\n', 't': '\t'}
+
+// no error: invalid literals should be caught by scanner
+func unquote(s string) string {
+	u, q, esc := make([]rune, 0, len(s)), false, false
+	for _, c := range s {
+		if esc {
+			uc, ok := unescape[c]
+			switch {
+			case ok:
+				u = append(u, uc)
+				fallthrough
+			case !q && c == '\n':
+				esc = false
+				continue
+			}
+			panic("invalid escape sequence")
+		}
+		switch c {
+		case '"':
+			q = !q
+		case '\\':
+			esc = true
+		default:
+			u = append(u, c)
+		}
+	}
+	if q {
+		panic("missing end quote")
+	}
+	if esc {
+		panic("invalid escape sequence")
+	}
+	return string(u)
+}
+
+func readInto(config interface{}, fset *token.FileSet, file *token.File, src []byte) error {
+	var s scanner.Scanner
+	var errs scanner.ErrorList
+	s.Init(file, src, func(p token.Position, m string) { errs.Add(p, m) }, 0)
+	sect, sectsub := "", ""
+	pos, tok, lit := s.Scan()
+	errfn := func(msg string) error {
+		return fmt.Errorf("%s: %s", fset.Position(pos), msg)
+	}
+	for {
+		if errs.Len() > 0 {
+			return errs.Err()
+		}
+		switch tok {
+		case token.EOF:
+			return nil
+		case token.EOL, token.COMMENT:
+			pos, tok, lit = s.Scan()
+		case token.LBRACK:
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				return errs.Err()
+			}
+			if tok != token.IDENT {
+				return errfn("expected section name")
+			}
+			sect, sectsub = lit, ""
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				return errs.Err()
+			}
+			if tok == token.STRING {
+				sectsub = unquote(lit)
+				if sectsub == "" {
+					return errfn("empty subsection name")
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					return errs.Err()
+				}
+			}
+			if tok != token.RBRACK {
+				if sectsub == "" {
+					return errfn("expected subsection name or right bracket")
+				}
+				return errfn("expected right bracket")
+			}
+			pos, tok, lit = s.Scan()
+			if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+				return errfn("expected EOL, EOF, or comment")
+			}
+			// If a section/subsection header was found, ensure a
+			// container object is created, even if there are no
+			// variables further down.
+			err := set(config, sect, sectsub, "", true, "")
+			if err != nil {
+				return err
+			}
+		case token.IDENT:
+			if sect == "" {
+				return errfn("expected section header")
+			}
+			n := lit
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				return errs.Err()
+			}
+			blank, v := tok == token.EOF || tok == token.EOL || tok == token.COMMENT, ""
+			if !blank {
+				if tok != token.ASSIGN {
+					return errfn("expected '='")
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					return errs.Err()
+				}
+				if tok != token.STRING {
+					return errfn("expected value")
+				}
+				v = unquote(lit)
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					return errs.Err()
+				}
+				if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+					return errfn("expected EOL, EOF, or comment")
+				}
+			}
+			err := set(config, sect, sectsub, n, blank, v)
+			if err != nil {
+				return err
+			}
+		default:
+			if sect == "" {
+				return errfn("expected section header")
+			}
+			return errfn("expected section header or variable declaration")
+		}
+	}
+	panic("never reached")
+}
+
+// ReadInto reads gcfg formatted data from reader and sets the values into the
+// corresponding fields in config.
+func ReadInto(config interface{}, reader io.Reader) error {
+	src, err := ioutil.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile("", fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}
+
+// ReadStringInto reads gcfg formatted data from str and sets the values into
+// the corresponding fields in config.
+func ReadStringInto(config interface{}, str string) error {
+	r := strings.NewReader(str)
+	return ReadInto(config, r)
+}
+
+// ReadFileInto reads gcfg formatted data from the file filename and sets the
+// values into the corresponding fields in config.
+func ReadFileInto(config interface{}, filename string) error {
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	src, err := ioutil.ReadAll(f)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile(filename, fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}