web/xynt/xynt-http-streaming.js

   1 function globst() {
   2     this.st = -1;
   3     this.st_loc = -1;
   4     this.st_loc_new = -1;
   5     this.comms  = new Array;
   6 }
   7
   8 globst.prototype = {
   9     st: -1,
  10     st_loc: -1,
  11     st_loc_new: -1,
  12     comms: null,
  13     sleep_hd: null,
  14
  15     sleep: function(delay) {
  16         st.st_loc_new++;
  17
  18         this.sleep_hdl = setTimeout(function(obj){ if (obj.st_loc_new > obj.st_loc) { obj.st_loc++; obj.sleep_hdl = null; }},
  19                                    delay, this);
  20     },
  21
  22     abort: function() {
  23         if (this.sleep_hdl != null) {
  24             clearTimeout(this.sleep_hdl);
  25             this.sleep_hdl = null;
  26         }
  27     }
  28 }
  29
  30 function http_streaming(win, cons)
  31 {
  32     this.console = cons;
  33     this.win = win;
  34     this.doc = win.document;
  35     this.keepalive_old = -1;
  36     this.keepalive_new = -1;
  37     this.gst = new globst();
  38     this.cmdproc = function(com){eval(com);}
  39 }
  40
  41 http_streaming.prototype = {
  42     console:           null,
  43     win:               null,
  44     doc:               null,
  45     ifra:              null,
  46     page:              null,
  47     watchdog_hdl:      null,
  48     keepalive_old:    -1,
  49     keepalive_new:    -1,
  50     keepalives_equal:  0,
  51     keepalives_eq_max: 6,
  52     watchdog_timeout:  100,
  53     watchdog_ct:       0,
  54     watchdog_checktm:  20,
  55     watchable:         false,
  56     gst:               null,
  57     restart_n:         0,
  58     cmdproc:           null,
  59     comm_match:        /_*@BEGIN@(.*?)@END@/g,
  60     comm_clean:        /_*@BEGIN@(.*?)@END@/,
  61     ctx_old:           "",
  62     ctx_old_len:       0,
  63     // ctx_new:           "",
  64     ctx_new_len:       0,
  65     stream:            "",
  66
  67     start: function(page) {
  68         this.log("http_streaming:start restart: "+this.restart_n);
  69         this.keepalives_equal = 0;
  70         this.ifra = this.doc.createElement("iframe");
  71         this.ifra.style.visibility = "hidden";
  72         this.doc.body.appendChild(this.ifra);
  73         if (page != null)
  74             this.page = page;
  75         // this.log(this.ifra);
  76         this.ifra.contentWindow.location.href = this.page;
  77         this.watchdog_ct  = 0;
  78         this.watchdog_hdl = setTimeout(function(obj) { obj.log("tout1"); obj.watchdog(); }, this.watchdog_timeout, this);
  79     },
  80
  81     watchdog: function () {
  82         var i, again;
  83         var comm_newpart, comm_len, comm_arr;
  84
  85         // WATCHDOGING THE CONNECTION
  86         if ( (this.watchdog_ct % this.watchdog_checktm) == 0 || !this.watchable) {
  87             this.log("hs::watchdog: start, cur equal times: "+this.keepalives_equal);
  88             if (!this.watchable) {
  89                 do {
  90                     if (typeof(this.ifra.contentWindow.http_streaming) == 'undefined')
  91                         break;
  92                     /*
  93                       on IE7 the the window frame scope is cleaned after the href is set, so we wait
  94                       for a well know variable value before assign this object value to it (OO is a passion)
  95                     */
  96                     if (this.ifra.contentWindow.http_streaming == "ready") {
  97                         this.ifra.contentWindow.http_streaming = this;
  98                         this.watchable = true;
  99                         this.log("hs::watchdog: watchable = yes");
 100                     }
 101                 } while (false);
 102             }
 103             this.log("hs::watchdog: this.keepalive_old: "+this.keepalive_old+" this.keepalive_new: "+this.keepalive_new);
 104             if (this.keepalive_old == this.keepalive_new) {
 105                 this.keepalives_equal++;
 106             }
 107             else {
 108                 this.keepalive_old = this.keepalive_new;
 109                 this.keepalives_equal = 0;
 110             }
 111
 112             if (this.keepalives_equal > this.keepalives_eq_max) {
 113                 this.log("hs::watchdog: MAX ACHIEVED "+this.keepalives_equal);
 114                 this.reload();
 115                 return;
 116             }
 117         }
 118
 119         // PICK COMMANDS FROM STREAM
 120         do {
 121             // CHECK: maybe again here isn't needed
 122             again = 0;
 123             if (typeof(this.ifra.contentWindow.ctx_new) == 'undefined')
 124                 break;
 125             if (this.ifra.contentWindow.ctx_new.length == this.ctx_old_len) {
 126                 // this.ctx_new = this.ctx_old = "";
 127                 // FIXME find a more robust clean method
 128                 break;
 129             }
 130             this.log("new: "+ this.ifra.contentWindow.ctx_new.length + "  old: "+this.ctx_old_len);
 131             this.keepalive_new++;
 132             for (i = this.ctx_old_len ; i < this.ifra.contentWindow.ctx_new.length ; i++) {
 133                 if (this.ifra.contentWindow.ctx_new[i] != '_')
 134                     break;
 135             }
 136             if (i == this.ifra.contentWindow.ctx_new.length) {
 137                 this.ctx_old_len = i;
 138                 break;
 139             }
 140             comm_newpart = this.ifra.contentWindow.ctx_new.substr(this.ctx_old_len);
 141             comm_len = 0;
 142             comm_arr = comm_newpart.match(this.comm_match);
 143
 144             if (comm_arr) {
 145                 for (i = 0 ; i < comm_arr.length ; i++) {
 146                     var temp = comm_arr[i].replace(this.comm_clean,"$1").split("|");
 147
 148                     this.gst.comms = this.gst.comms.concat(temp);
 149                     // XX alert("COMM_ARR["+i+"]: "+comm_arr[i]+"  LEN:"+comm_arr[i].length);
 150                     comm_len += comm_arr[i].length;
 151                 }
 152                 this.ctx_old += comm_newpart.substr(0,comm_len);
 153                 again = 1;
 154             }
 155             this.ctx_old_len = this.ctx_old.length;
 156         } while (again);
 157
 158
 159
 160         // EXECUTION OF STREAM COMMANDS
 161         do {
 162             again = 0;
 163             //MOP ?? xhrrestart = 0;
 164             if (this.gst.st_loc < this.gst.st_loc_new) {
 165                 // there is some slow actions running
 166                 break;
 167             }
 168             else if (this.gst.comms.length > 0) {
 169                 var singlecomm;
 170
 171                 singlecomm = this.gst.comms.shift();
 172                 // alert("EXE"+gugu);
 173                 // $("xhrdeltalog").innerHTML = "EVALL: "+singlecomm.replace("<", "&lt;", "g"); +"<br>";
 174                 //xx this.hbit("+");
 175
 176                 this.cmdproc(singlecomm);
 177                 again = 1;
 178             }
 179         } while (again);
 180
 181
 182         this.watchdog_ct++;
 183         this.watchdog_hdl = setTimeout(function(obj) { /* obj.log("tout2"); */ obj.watchdog(); }, this.watchdog_timeout, this);
 184         return;
 185     },
 186
 187     keepalive: function (s) {
 188         this.log("hs::keepalive");
 189         if (s != null) {
 190             this.log(s);
 191             this.ifra.contentWindow.ctx_new += "@BEGIN@"+s+"@END@";
 192         }
 193         else {
 194             this.ifra.contentWindow.ctx_new += "_";
 195         }
 196         // this.keepalive_new++;
 197     },
 198
 199     abort: function () {
 200         this.gst.abort();
 201         if (this.watchdog_hdl != null) {
 202             clearTimeout(this.watchdog_hdl);
 203             this.watchdog_hdl = null;
 204         }
 205
 206         this.restart_n++;
 207         this.log("hs::reload");
 208         this.watchable = false;
 209         if (this.ifra != null) {
 210             this.doc.body.removeChild(this.ifra);
 211             delete this.ifra;
 212             this.ifra = null;
 213         }
 214         this.ctx_old = "";
 215         this.ctx_old_len = 0;
 216     },
 217
 218     reload: function () {
 219         this.abort();
 220         this.start(null);
 221     },
 222
 223     log: function (s) {
 224         if (this.console != null) {
 225             return (this.console.log(s));
 226         }
 227     }
 228 }