michael@0: function parseQuery(request, key) {
michael@0:   var params = request.queryString.split('&');
michael@0:   for (var j = 0; j < params.length; ++j) {
michael@0:     var p = params[j];
michael@0: 	if (p == key)
michael@0: 	  return true;
michael@0:     if (p.indexOf(key + "=") == 0)
michael@0: 	  return p.substring(key.length + 1);
michael@0: 	if (p.indexOf("=") < 0 && key == "")
michael@0: 	  return p;
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: function push32BE(array, input) {
michael@0:   array.push(String.fromCharCode((input >> 24) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 16) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 8) & 0xff));
michael@0:   array.push(String.fromCharCode((input) & 0xff));
michael@0: }
michael@0: 
michael@0: function push32LE(array, input) {
michael@0:   array.push(String.fromCharCode((input) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 8) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 16) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 24) & 0xff));
michael@0: }
michael@0: 
michael@0: function push16LE(array, input) {
michael@0:   array.push(String.fromCharCode((input) & 0xff));
michael@0:   array.push(String.fromCharCode((input >> 8) & 0xff));
michael@0: }
michael@0: 
michael@0: function buildWave(samples, sample_rate) {
michael@0:   const RIFF_MAGIC = 0x52494646;
michael@0:   const WAVE_MAGIC = 0x57415645;
michael@0:   const FRMT_MAGIC = 0x666d7420;
michael@0:   const DATA_MAGIC = 0x64617461;
michael@0:   const RIFF_SIZE = 44;
michael@0: 
michael@0:   var header = [];
michael@0:   push32BE(header, RIFF_MAGIC);
michael@0:   push32LE(header, RIFF_SIZE + samples.length * 2);
michael@0:   push32BE(header, WAVE_MAGIC);
michael@0:   push32BE(header, FRMT_MAGIC);
michael@0:   push32LE(header, 16);
michael@0:   push16LE(header, 1);
michael@0:   push16LE(header, 1);
michael@0:   push32LE(header, sample_rate);
michael@0:   push32LE(header, sample_rate);
michael@0:   push16LE(header, 2);
michael@0:   push16LE(header, 16);
michael@0:   push32BE(header, DATA_MAGIC);
michael@0:   push32LE(header, samples.length * 2);
michael@0:   for (var i = 0; i < samples.length; ++i) {
michael@0:     push16LE(header, samples[i], 2);
michael@0:   }
michael@0:   return header;
michael@0: }
michael@0: 
michael@0: const Ci = Components.interfaces;
michael@0: const CC = Components.Constructor;
michael@0: const Timer = CC("@mozilla.org/timer;1", "nsITimer", "initWithCallback");
michael@0: const BinaryOutputStream = CC("@mozilla.org/binaryoutputstream;1",
michael@0:                              "nsIBinaryOutputStream",
michael@0:                              "setOutputStream");
michael@0: 
michael@0: function poll(f) {
michael@0:   if (f()) {
michael@0:     return;
michael@0:   }
michael@0:   new Timer(function() { poll(f); }, 100, Ci.nsITimer.TYPE_ONE_SHOT);
michael@0: }
michael@0: 
michael@0: function handleRequest(request, response)
michael@0: {
michael@0:   var cancel = parseQuery(request, "cancelkey");
michael@0:   if (cancel) {
michael@0:     setState(cancel[1], "cancelled");
michael@0:     response.setStatusLine(request.httpVersion, 200, "OK");
michael@0:     response.write("Cancel approved!");
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   var samples = [];
michael@0:   for (var i = 0; i < 1000000; ++i) {
michael@0:     samples.push(0);
michael@0:   }
michael@0:   var bytes = buildWave(samples, 44100).join("");
michael@0: 
michael@0:   var key = parseQuery(request, "key");
michael@0:   response.setHeader("Content-Type", "audio/x-wav");
michael@0:   response.setHeader("Content-Length", ""+bytes.length, false);
michael@0: 
michael@0:   var out = new BinaryOutputStream(response.bodyOutputStream);
michael@0: 
michael@0:   var start = 0, end = bytes.length - 1;
michael@0:   if (request.hasHeader("Range"))
michael@0:   {
michael@0:     var rangeMatch = request.getHeader("Range").match(/^bytes=(\d+)?-(\d+)?$/);
michael@0: 
michael@0:     if (rangeMatch[1] !== undefined)
michael@0:       start = parseInt(rangeMatch[1], 10);
michael@0: 
michael@0:     if (rangeMatch[2] !== undefined)
michael@0:       end = parseInt(rangeMatch[2], 10);
michael@0: 
michael@0:     // No start given, so the end is really the count of bytes from the
michael@0:     // end of the file.
michael@0:     if (start === undefined)
michael@0:     {
michael@0:       start = Math.max(0, bytes.length - end);
michael@0:       end   = bytes.length - 1;
michael@0:     }
michael@0: 
michael@0:     // start and end are inclusive
michael@0:     if (end === undefined || end >= bytes.length)
michael@0:       end = bytes.length - 1;
michael@0: 
michael@0:     if (end < start)
michael@0:     {
michael@0:       response.setStatusLine(request.httpVersion, 200, "OK");
michael@0:       start = 0;
michael@0:       end = bytes.length - 1;
michael@0:     }
michael@0:     else
michael@0:     {
michael@0:       response.setStatusLine(request.httpVersion, 206, "Partial Content");
michael@0:       var contentRange = "bytes " + start + "-" + end + "/" + bytes.length;
michael@0:       response.setHeader("Content-Range", contentRange);
michael@0:     }
michael@0:   }
michael@0:   
michael@0:   if (start > 0) {
michael@0:     // Send all requested data
michael@0:     out.write(bytes.slice(start, end + 1), end + 1 - start);
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // Write the first 1.2M of the Wave file. We know the cache size is set to
michael@0:   // 100K so this will fill the cache and and cause a "suspend" event on
michael@0:   // the loading element.
michael@0:   out.write(bytes, 1200000);
michael@0: 
michael@0:   response.processAsync();
michael@0:   // Now wait for the message to cancel this response
michael@0:   poll(function() {
michael@0:     if (getState(key[1]) != "cancelled") {
michael@0:       return false;
michael@0:     }
michael@0:     response.finish();
michael@0:     return true;
michael@0:   });
michael@0: }