text: // 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.
  
  // Query String Utilities
  
  var QueryString = exports;
  
  
  function charCode(c) {
    return c.charCodeAt(0);
  }
  
  
  // a safe fast alternative to decodeURIComponent
  QueryString.unescapeBuffer = function(s, decodeSpaces) {
    var out = new Buffer(s.length);
    var state = 'CHAR'; // states: CHAR, HEX0, HEX1
    var n, m, hexchar;
  
    for (var inIndex = 0, outIndex = 0; inIndex <= s.length; inIndex++) {
      var c = s.charCodeAt(inIndex);
      switch (state) {
        case 'CHAR':
          switch (c) {
            case charCode('%'):
              n = 0;
              m = 0;
              state = 'HEX0';
              break;
            case charCode('+'):
              if (decodeSpaces) c = charCode(' ');
              // pass thru
            default:
              out[outIndex++] = c;
              break;
          }
          break;
  
        case 'HEX0':
          state = 'HEX1';
          hexchar = c;
          if (charCode('0') <= c && c <= charCode('9')) {
            n = c - charCode('0');
          } else if (charCode('a') <= c && c <= charCode('f')) {
            n = c - charCode('a') + 10;
          } else if (charCode('A') <= c && c <= charCode('F')) {
            n = c - charCode('A') + 10;
          } else {
            out[outIndex++] = charCode('%');
            out[outIndex++] = c;
            state = 'CHAR';
            break;
          }
          break;
  
        case 'HEX1':
          state = 'CHAR';
          if (charCode('0') <= c && c <= charCode('9')) {
            m = c - charCode('0');
          } else if (charCode('a') <= c && c <= charCode('f')) {
            m = c - charCode('a') + 10;
          } else if (charCode('A') <= c && c <= charCode('F')) {
            m = c - charCode('A') + 10;
          } else {
            out[outIndex++] = charCode('%');
            out[outIndex++] = hexchar;
            out[outIndex++] = c;
            break;
          }
          out[outIndex++] = 16 * n + m;
          break;
      }
    }
  
    // TODO support returning arbitrary buffers.
  
    return out.slice(0, outIndex - 1);
  };
  
  
  QueryString.unescape = function(s, decodeSpaces) {
    return QueryString.unescapeBuffer(s, decodeSpaces).toString();
  };
  
  
  QueryString.escape = function(str) {
    return encodeURIComponent(str);
  };
  
  var stringifyPrimitive = function(v) {
    switch (typeof v) {
      case 'string':
        return v;
  
      case 'boolean':
        return v ? 'true' : 'false';
  
      case 'number':
        return isFinite(v) ? v : '';
  
      default:
        return '';
    }
  };
  
  
  QueryString.stringify = QueryString.encode = function(obj, sep, eq, name) {
    sep = sep || '&';
    eq = eq || '=';
    obj = (obj === null) ? undefined : obj;
  
    switch (typeof obj) {
      case 'object':
        return Object.keys(obj).map(function(k) {
          if (Array.isArray(obj[k])) {
            return obj[k].map(function(v) {
              return QueryString.escape(stringifyPrimitive(k)) +
                     eq +
                     QueryString.escape(stringifyPrimitive(v));
            }).join(sep);
          } else {
            return QueryString.escape(stringifyPrimitive(k)) +
                   eq +
                   QueryString.escape(stringifyPrimitive(obj[k]));
          }
        }).join(sep);
  
      default:
        if (!name) return '';
        return QueryString.escape(stringifyPrimitive(name)) + eq +
               QueryString.escape(stringifyPrimitive(obj));
    }
  };
  
  // Parse a key=val string.
  QueryString.parse = QueryString.decode = function(qs, sep, eq) {
    sep = sep || '&';
    eq = eq || '=';
    var obj = {};
  
    if (typeof qs !== 'string' || qs.length === 0) {
      return obj;
    }
  
    qs.split(sep).forEach(function(kvp) {
      var x = kvp.split(eq);
      var k = QueryString.unescape(x[0], true);
      var v = QueryString.unescape(x.slice(1).join(eq), true);
  
      if (!(k in obj)) {
        obj[k] = v;
      } else if (!Array.isArray(obj[k])) {
        obj[k] = [obj[k], v];
      } else {
        obj[k].push(v);
      }
    });
  
    return obj;
  };