gitweb - printer.go

     1  package main
     2  
     3  import (
     4  	"io"
     5  
     6  	"vimagination.zapto.org/memio"
     7  	"vimagination.zapto.org/parser"
     8  	"vimagination.zapto.org/rwcount"
     9  )
    10  
    11  const (
    12  	TokenUnknown parser.TokenType = iota
    13  	TokenComment
    14  )
    15  
    16  type Tokens struct {
    17  	Unknown, Comment parser.TokenType
    18  }
    19  
    20  var tokens = Tokens{
    21  	Unknown: TokenUnknown,
    22  	Comment: TokenComment,
    23  }
    24  
    25  func handleTemplate(file *File, w io.Writer, ch <-chan parser.Token, err chan<- error) {
    26  	err <- config.prettyTemplate.Execute(w, struct {
    27  		*File
    28  		Tokens     <-chan parser.Token
    29  		TokenTypes *Tokens
    30  	}{
    31  		File:       file,
    32  		Tokens:     ch,
    33  		TokenTypes: &tokens,
    34  	})
    35  }
    36  
    37  func prettify(file *File, w io.Writer, r io.Reader, tf parser.TokenFunc) (int64, error) {
    38  	if tf == nil {
    39  		return io.Copy(w, r)
    40  	}
    41  	c := make(chan parser.Token)
    42  	e := make(chan error)
    43  	go handleTemplate(file, w, c, e)
    44  	var (
    45  		rw rwcount.Reader
    46  		p  parser.Parser
    47  	)
    48  	if lr, ok := r.(*memio.LimitedBuffer); ok {
    49  		rw.Count = int64(len(*lr))
    50  		p = parser.New(parser.NewByteTokeniser(*lr))
    51  	} else {
    52  		rw.Reader = r
    53  		p = parser.New(parser.NewReaderTokeniser(&rw))
    54  	}
    55  	p.TokeniserState(tf)
    56  	for {
    57  		tk, err := p.GetToken()
    58  		if err != nil {
    59  			close(c)
    60  			<-e
    61  			return rw.Count, err
    62  		}
    63  		if tk.Type == parser.TokenDone {
    64  			close(c)
    65  			break
    66  		}
    67  		select {
    68  		case c <- tk:
    69  		case err := <-e:
    70  			return rw.Count, err
    71  		}
    72  	}
    73  	if err := <-e; err != nil {
    74  		return rw.Count, err
    75  	}
    76  	if rw.Err == io.EOF {
    77  		rw.Err = nil
    78  	}
    79  	return rw.Count, rw.Err
    80  }
    81