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// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// 'Software'), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
var cares = process.binding('cares_wrap'),
net = require('net'),
isIp = net.isIP;
function errnoException(errorno, syscall) {
// TODO make this more compatible with ErrnoException from src/node.cc
// Once all of Node is using this function the ErrnoException from
// src/node.cc should be removed.
// For backwards compatibility. libuv returns ENOENT on NXDOMAIN.
if (errorno == 'ENOENT') {
errorno = 'ENOTFOUND';
}
var e = new Error(syscall + ' ' + errorno);
e.errno = e.code = errorno;
e.syscall = syscall;
return e;
}
// c-ares invokes a callback either synchronously or asynchronously,
// but the dns API should always invoke a callback asynchronously.
//
// This function makes sure that the callback is invoked asynchronously.
// It returns a function that invokes the callback within nextTick().
//
// To avoid invoking unnecessary nextTick(), `immediately` property of
// returned function should be set to true after c-ares returned.
//
// Usage:
//
// function someAPI(callback) {
// callback = makeAsync(callback);
// channel.someAPI(..., callback);
// callback.immediately = true;
// }
function makeAsync(callback) {
if (typeof callback !== 'function') {
return callback;
}
return function asyncCallback() {
if (asyncCallback.immediately) {
// The API already returned, we can invoke the callback immediately.
callback.apply(null, arguments);
} else {
var args = arguments;
process.nextTick(function() {
callback.apply(null, args);
});
}
};
}
// Easy DNS A/AAAA look up
// lookup(domain, [family,] callback)
exports.lookup = function(domain, family, callback) {
// parse arguments
if (arguments.length === 2) {
callback = family;
family = 0;
} else if (!family) {
family = 0;
} else {
family = +family;
if (family !== 4 && family !== 6) {
throw new Error('invalid argument: `family` must be 4 or 6');
}
}
callback = makeAsync(callback);
if (!domain) {
callback(null, null, family === 6 ? 6 : 4);
return {};
}
// Hack required for Windows because Win7 removed the
// localhost entry from c:\WINDOWS\system32\drivers\etc\hosts
// See http://daniel.haxx.se/blog/2011/02/21/localhost-hack-on-windows/
// TODO Remove this once c-ares handles this problem.
if (process.platform == 'win32' && domain == 'localhost') {
callback(null, '127.0.0.1', 4);
return {};
}
var matchedFamily = net.isIP(domain);
if (matchedFamily) {
callback(null, domain, matchedFamily);
return {};
}
function onanswer(addresses) {
if (addresses) {
if (family) {
callback(null, addresses[0], family);
} else {
callback(null, addresses[0], addresses[0].indexOf(':') >= 0 ? 6 : 4);
}
} else {
callback(errnoException(process._errno, 'getaddrinfo'));
}
}
var wrap = cares.getaddrinfo(domain, family);
if (!wrap) {
throw errnoException(process._errno, 'getaddrinfo');
}
wrap.oncomplete = onanswer;
callback.immediately = true;
return wrap;
};
function resolver(bindingName) {
var binding = cares[bindingName];
return function query(name, callback) {
function onanswer(status, result) {
if (!status) {
callback(null, result);
} else {
callback(errnoException(process._errno, bindingName));
}
}
callback = makeAsync(callback);
var wrap = binding(name, onanswer);
if (!wrap) {
throw errnoException(process._errno, bindingName);
}
callback.immediately = true;
return wrap;
}
}
var resolveMap = {};
exports.resolve4 = resolveMap.A = resolver('queryA');
exports.resolve6 = resolveMap.AAAA = resolver('queryAaaa');
exports.resolveCname = resolveMap.CNAME = resolver('queryCname');
exports.resolveMx = resolveMap.MX = resolver('queryMx');
exports.resolveNs = resolveMap.NS = resolver('queryNs');
exports.resolveTxt = resolveMap.TXT = resolver('queryTxt');
exports.resolveSrv = resolveMap.SRV = resolver('querySrv');
exports.resolveNaptr = resolveMap.NAPTR = resolver('queryNaptr');
exports.reverse = resolveMap.PTR = resolver('getHostByAddr');
exports.resolve = function(domain, type_, callback_) {
var resolver, callback;
if (typeof type_ == 'string') {
resolver = resolveMap[type_];
callback = callback_;
} else {
resolver = exports.resolve4;
callback = type_;
}
if (typeof resolver === 'function') {
return resolver(domain, callback);
} else {
throw new Error('Unknown type "' + type_ + '"');
}
};
exports.getServers = function() {
return cares.getServers();
};
exports.setServers = function(servers) {
// cache the original servers because in the event of an error setting the
// servers cares won't have any servers available for resolution
var orig = cares.getServers();
var newSet = [];
servers.forEach(function(serv) {
var ver = isIp(serv);
if (ver)
return newSet.push([ver, serv]);
var match = serv.match(/\[(.*)\](:\d+)?/);
// we have an IPv6 in brackets
if (match) {
ver = isIp(match[1]);
if (ver)
return newSet.push([ver, match[1]]);
}
var s = serv.split(/:\d+$/)[0];
ver = isIp(s);
if (ver)
return newSet.push([ver, s]);
throw new Error('IP address is not properly formatted: ' + serv);
});
var r = cares.setServers(newSet);
if (r) {
// reset the servers to the old servers, because ares probably unset them
cares.setServers(orig.join(','));
var err = cares.strerror(r);
throw new Error('c-ares failed to set servers: "' + err +
'" [' + servers + ']');
}
};
// ERROR CODES
exports.NODATA = 'ENODATA';
exports.FORMERR = 'EFORMERR';
exports.SERVFAIL = 'ESERVFAIL';
exports.NOTFOUND = 'ENOTFOUND';
exports.NOTIMP = 'ENOTIMP';
exports.REFUSED = 'EREFUSED';
exports.BADQUERY = 'EBADQUERY';
exports.ADNAME = 'EADNAME';
exports.BADFAMILY = 'EBADFAMILY';
exports.BADRESP = 'EBADRESP';
exports.CONNREFUSED = 'ECONNREFUSED';
exports.TIMEOUT = 'ETIMEOUT';
exports.EOF = 'EOF';
exports.FILE = 'EFILE';
exports.NOMEM = 'ENOMEM';
exports.DESTRUCTION = 'EDESTRUCTION';
exports.BADSTR = 'EBADSTR';
exports.BADFLAGS = 'EBADFLAGS';
exports.NONAME = 'ENONAME';
exports.BADHINTS = 'EBADHINTS';
exports.NOTINITIALIZED = 'ENOTINITIALIZED';
exports.LOADIPHLPAPI = 'ELOADIPHLPAPI';
exports.ADDRGETNETWORKPARAMS = 'EADDRGETNETWORKPARAMS';
exports.CANCELLED = 'ECANCELLED';