app.js

#!/usr/bin/env node

// Copyright (c) 2012, Matt Godbolt
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions are met:
// 
//     * Redistributions of source code must retain the above copyright notice, 
//       this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright 
//       notice, this list of conditions and the following disclaimer in the 
//       documentation and/or other materials provided with the distribution.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
// POSSIBILITY OF SUCH DAMAGE.

var nopt = require('nopt'),
    os = require('os'),
    props = require('./lib/properties'),
    querystring = require('querystring'),
    connect = require('connect'),
    child_process = require('child_process'),
    temp = require('temp'),
    path = require('path'),
    async = require('async'),
    fs = require('fs');

var opts = nopt({
        'env': [String],
        'rootDir': [String]});

var propHierarchy = [
    'defaults', 
    opts.env || 'dev',
    os.hostname()];

var rootDir = opts.rootDir || './etc';

props.initialize(rootDir + '/config', propHierarchy);

var port = props.get('gcc-explorer', 'port', 10240);

function checkOptions(options) {
    var okOptions = new RegExp(props.get('gcc-options', 'whitelistRe', '.*'));
    var badOptions = new RegExp(props.get('gcc-options', 'blacklistRe'));
    var error = [];
    options.forEach(function(option) {
        if (!option.match(okOptions) || option.match(badOptions)) {
            error.push(option);
        }
    });
    if (error.length > 0) return "Bad options: " + error.join(", ");
    return null;
}

function checkSource(source) {
    var re = /^\s*#include(_next)?\s+["<"](\/|.*\.\.)/;
    var failed = [];
    source.split('\n').forEach(function(line, index) {
        if (line.match(re)) {
            failed.push("<stdin>:" + (index + 1) + ":1: no absolute or relative includes please");
        }
    });
    if (failed.length > 0) return failed.join("\n");
    return null;
}

function compile(req, res) {
    var source = req.body.source;
    var compiler = req.body.compiler;
    if (getCompilerExecutables().indexOf(compiler) < 0) {
        return res.end(JSON.stringify({code: -1, stderr: "bad compiler " + compiler}));
    }
    var options = req.body.options.split(' ').filter(function(x){return x!=""});
    var optionsErr = checkOptions(options);
    if (optionsErr) {
        return res.end(JSON.stringify({code: -1, stderr: optionsErr}));
    }
    var sourceErr = checkSource(source);
    if (sourceErr) {
        return res.end(JSON.stringify({code: -1, stderr: sourceErr}));
    }
    temp.mkdir('gcc-explorer-compiler', function(err, dirPath) {
        if (err) {
            return res.end(JSON.stringify({code: -1, stderr: "Unable to open temp file: " + err}));
        }
        var outputFilename = path.join(dirPath, 'output.S');
        options = options.concat([ '-x', 'c++', '-o', outputFilename, '-S', '-']);
        var child = child_process.spawn(
            compiler,
            options
            );
        var stdout = "";
        var stderr = "";
        var timeout = setTimeout(function() {
            child.kill();
            stderr += "\nKilled - processing time exceeded";
        }, props.get("gcc-explorer", "compileTimeoutMs", 100));
        child.stdout.on('data', function (data) { stdout += data; });
        child.stderr.on('data', function (data) { stderr += data; });
        child.on('exit', function (code) {
            clearTimeout(timeout);
            child_process.exec('cat "' + outputFilename + '" | c++filt', function(err, filt_stdout, filt_stderr) {
                var data = filt_stdout;
                if (err) {
                    data = '<No output>';
                }

                res.end(JSON.stringify({
                    stdout: stdout,
                    stderr: stderr,
                    asm: data,
                    code: code }));
                fs.unlink(outputFilename, function() { fs.rmdir(dirPath); });
            });
        });
        child.stdin.write(source);
        child.stdin.end();
    });
}

function loadSources() {
    var sourcesDir = "lib/sources";
    var sources = fs.readdirSync(sourcesDir)
        .filter(function(file) { return file.match(/.*\.js$/); })
        .map(function(file) { return require("./" + path.join(sourcesDir, file)); });
    return sources;
}

var fileSources = loadSources();
var sourceToHandler = {};
fileSources.forEach(function(source) { sourceToHandler[source.urlpart] = source; });

function compareOn(key) {
    return function(xObj, yObj) {
        var x = xObj[key];
        var y = yObj[key];
        if (x < y) return -1;
        if (x > y) return 1;
        return 0;
    };
}

function getSources(req, res) {
    var sources = fileSources.map(function(source) { 
        return {name: source.name, urlpart: source.urlpart};
    });
    res.end(JSON.stringify(sources.sort(compareOn("name"))));
}

function getSource(req, res, next) {
    var bits = req.url.split("/");
    var handler = sourceToHandler[bits[1]];
    if (!handler) {
        next();
        return;
    }
    var action = bits[2];
    if (action == "list") action = handler.list;
    else if (action == "load") action = handler.load;
    else if (action == "save") action = handler.save;
    else action = null;
    if (action == null) {
        next();
        return;
    }
    action.apply(handler, bits.slice(3).concat(function(err, response) {
        if (err) {
            res.end(JSON.stringify({err: err}));
        } else {
            res.end(JSON.stringify(response));
        }}));
}

function getCompilerExecutables() {
    return props.get("gcc-explorer", "compilers", "/usr/bin/g++").split(":");
}

function getCompilers(req, res) {
    async.map(getCompilerExecutables(),
        function (compiler, callback) {
            fs.stat(compiler, function(err, result) {
                if (err) {
                    callback(null, null);
                } else {
                    child_process.exec(compiler + ' --version', function(err, output) {
                        if (err) {
                            callback(null, null);
                        } else {
                            callback(null, {exe: compiler, version: output.split('\n')[0]});
                        }
                    });
                }
            });
        },
        function (err, all) {
            all = all.filter(function(x){return x!=null;});
            res.end(JSON.stringify(all));
        }
    );
}

// WebServer.
var webServer = connect();
webServer
    .use(connect.logger())
    .use(connect.favicon('static/favicon.ico'))
    .use(connect.static('static'))
    .use(connect.bodyParser())
    .use('/sources', getSources)
    .use('/source', getSource)
    .use('/compilers', getCompilers)
    .use('/compile', compile);


// GO!
console.log("=======================================");
console.log("Listening on http://" + os.hostname() + ":" + port + "/");
console.log("=======================================");
webServer.listen(port);