consolidate.go

// consolidate a LaTeX top-level source file into a single file in preparation
// for running through pandoc to generate an ePub.
package main

/*
   Copyright (c) 2012 Kyle Isom <kyle@tyrfingr.is>

   Permission to use, copy, modify, and distribute this software for any
   purpose with or without fee is hereby granted, provided that the 
   above copyright notice and this permission notice appear in all 
   copies.

   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL 
   WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED 
   WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE 
   AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
   DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA
   OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 
   TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 
   PERFORMANCE OF THIS SOFTWARE.
*/

import (
	"bufio"
	"flag"
	"fmt"
	"io"
	"io/ioutil"
	"os"
	"regexp"
)

var inFileName, outFileName string
var includeFile = regexp.MustCompile("^\\s*\\\\input{(.*)}$")
var endNewline = regexp.MustCompile("\n$")

func main() {
	outFN := flag.String("o", "gopherref_c.tex", "output file name")
	inFN := flag.String("i", "gopherref.tex", "input file name")
	flag.Parse()
	outFileName = *outFN
	inFileName = *inFN

	inFile, err := os.Open(inFileName)
	if err != nil {
		fmt.Println("[!] couldn't open ", inFileName)
		os.Exit(1)
	}

	buf := bufio.NewReader(inFile)

	fullLine := []byte{}
	for {
		line, isPrefix, err := buf.ReadLine()

		if err == io.EOF {
			break
		} else if err != nil {
			fmt.Printf("[!] unrecoverable error reading %s: %s\n",
				inFileName, err.Error())
			os.Exit(1)
		}
		fullLine = append(fullLine, line...)
		if isPrefix {
			continue
		}
		if includeFile.Match(fullLine) {
			includeFile := includeFile.ReplaceAll(fullLine, []byte("$1.tex"))
			fullLine, err = ioutil.ReadFile(string(includeFile))
			if err != nil {
				fmt.Printf("[!] unrecoverable error reading %s: %s\n",
					inFileName, err.Error())
				os.Exit(1)
			}

		}
                appendFile(outFileName, fullLine)
		fullLine = []byte{}
	}
}

func appendFile(fileName string, line []byte) {
	file, err := os.OpenFile(fileName, os.O_WRONLY|os.O_APPEND, 0600)
	if err != nil && os.IsNotExist(err) {
		file, err = os.Create(fileName)
	}

	if err != nil {
		fmt.Printf("[+] unrecoverable error writing %s: %s\n",
			fileName, err.Error())
	}
	defer file.Close()

	_, err = file.Write(line)
	if err != nil {
		fmt.Printf("[+] unrecoverable error writing %s: %s\n",
			fileName, err.Error())
	}
}