summaryrefslogtreecommitdiffstats
path: root/browser/components/sessionstore/SessionHistory.jsm
blob: 3d28d87db870a7c807cc417564cdfbbd348b18cf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */

"use strict";

this.EXPORTED_SYMBOLS = ["SessionHistory"];

const Cu = Components.utils;
const Cc = Components.classes;
const Ci = Components.interfaces;

Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");

XPCOMUtils.defineLazyModuleGetter(this, "Utils",
  "resource://gre/modules/sessionstore/Utils.jsm");

function debug(msg) {
  Services.console.logStringMessage("SessionHistory: " + msg);
}

/**
 * The external API exported by this module.
 */
this.SessionHistory = Object.freeze({
  isEmpty: function (docShell) {
    return SessionHistoryInternal.isEmpty(docShell);
  },

  collect: function (docShell) {
    return SessionHistoryInternal.collect(docShell);
  },

  restore: function (docShell, tabData) {
    SessionHistoryInternal.restore(docShell, tabData);
  }
});

/**
 * The internal API for the SessionHistory module.
 */
var SessionHistoryInternal = {
  /**
   * Returns whether the given docShell's session history is empty.
   *
   * @param docShell
   *        The docShell that owns the session history.
   */
  isEmpty: function (docShell) {
    let webNavigation = docShell.QueryInterface(Ci.nsIWebNavigation);
    let history = webNavigation.sessionHistory;
    if (!webNavigation.currentURI) {
      return true;
    }
    let uri = webNavigation.currentURI.spec;
    return uri == "about:blank" && history.count == 0;
  },

  /**
   * Collects session history data for a given docShell.
   *
   * @param docShell
   *        The docShell that owns the session history.
   */
  collect: function (docShell) {
    let loadContext = docShell.QueryInterface(Ci.nsILoadContext);
    let webNavigation = docShell.QueryInterface(Ci.nsIWebNavigation);
    let history = webNavigation.sessionHistory.QueryInterface(Ci.nsISHistoryInternal);

    let data = {entries: [], userContextId: loadContext.originAttributes.userContextId };

    if (history && history.count > 0) {
      // Loop over the transaction linked list directly so we can get the
      // persist property for each transaction.
      for (let txn = history.rootTransaction; txn; txn = txn.next) {
        let entry = this.serializeEntry(txn.sHEntry);
        entry.persist = txn.persist;
        data.entries.push(entry);
      }

      // Ensure the index isn't out of bounds if an exception was thrown above.
      data.index = Math.min(history.index + 1, data.entries.length);
    }

    // If either the session history isn't available yet or doesn't have any
    // valid entries, make sure we at least include the current page.
    if (data.entries.length == 0) {
      let uri = webNavigation.currentURI.spec;
      let body = webNavigation.document.body;
      // We landed here because the history is inaccessible or there are no
      // history entries. In that case we should at least record the docShell's
      // current URL as a single history entry. If the URL is not about:blank
      // or it's a blank tab that was modified (like a custom newtab page),
      // record it. For about:blank we explicitly want an empty array without
      // an 'index' property to denote that there are no history entries.
      if (uri != "about:blank" || (body && body.hasChildNodes())) {
        data.entries.push({
          url: uri,
          triggeringPrincipal_base64: Utils.SERIALIZED_SYSTEMPRINCIPAL
        });
        data.index = 1;
      }
    }

    return data;
  },

  /**
   * Get an object that is a serialized representation of a History entry.
   *
   * @param shEntry
   *        nsISHEntry instance
   * @return object
   */
  serializeEntry: function (shEntry) {
    let entry = { url: shEntry.URI.spec };

    // Save some bytes and don't include the title property
    // if that's identical to the current entry's URL.
    if (shEntry.title && shEntry.title != entry.url) {
      entry.title = shEntry.title;
    }
    if (shEntry.isSubFrame) {
      entry.subframe = true;
    }

    entry.charset = shEntry.URI.originCharset;

    let cacheKey = shEntry.cacheKey;
    if (cacheKey && cacheKey instanceof Ci.nsISupportsPRUint32 &&
        cacheKey.data != 0) {
      // XXXbz would be better to have cache keys implement
      // nsISerializable or something.
      entry.cacheKey = cacheKey.data;
    }
    entry.ID = shEntry.ID;
    entry.docshellID = shEntry.docshellID;

    // We will include the property only if it's truthy to save a couple of
    // bytes when the resulting object is stringified and saved to disk.
    if (shEntry.referrerURI) {
      entry.referrer = shEntry.referrerURI.spec;
      entry.referrerPolicy = shEntry.referrerPolicy;
    }

    if (shEntry.originalURI) {
      entry.originalURI = shEntry.originalURI.spec;
    }

    if (shEntry.loadReplace) {
      entry.loadReplace = shEntry.loadReplace;
    }

    if (shEntry.srcdocData)
      entry.srcdocData = shEntry.srcdocData;

    if (shEntry.isSrcdocEntry)
      entry.isSrcdocEntry = shEntry.isSrcdocEntry;

    if (shEntry.baseURI)
      entry.baseURI = shEntry.baseURI.spec;

    if (shEntry.contentType)
      entry.contentType = shEntry.contentType;

    if (shEntry.scrollRestorationIsManual) {
      entry.scrollRestorationIsManual = true;
    } else {
      let x = {}, y = {};
      shEntry.getScrollPosition(x, y);
      if (x.value != 0 || y.value != 0)
        entry.scroll = x.value + "," + y.value;
    }

    // Collect triggeringPrincipal data for the current history entry.
    // Please note that before Bug 1297338 there was no concept of a
    // principalToInherit. To remain backward/forward compatible we
    // serialize the principalToInherit as triggeringPrincipal_b64.
    // Once principalToInherit is well established (within FF55)
    // we can update this code, remove triggeringPrincipal_b64 and
    // just keep triggeringPrincipal_base64 as well as
    // principalToInherit_base64;  see Bug 1301666.
    if (shEntry.principalToInherit) {
      try {
        let principalToInherit = Utils.serializePrincipal(shEntry.principalToInherit);
        if (principalToInherit) {
          entry.triggeringPrincipal_b64 = principalToInherit;
          entry.principalToInherit_base64 = principalToInherit;
        }
      } catch (e) {
        debug(e);
      }
    }

    if (shEntry.triggeringPrincipal) {
      try {
        let triggeringPrincipal = Utils.serializePrincipal(shEntry.triggeringPrincipal);
        if (triggeringPrincipal) {
          entry.triggeringPrincipal_base64 = triggeringPrincipal;
        }
      } catch (e) {
        debug(e);
      }
    }

    entry.docIdentifier = shEntry.BFCacheEntry.ID;

    if (shEntry.stateData != null) {
      entry.structuredCloneState = shEntry.stateData.getDataAsBase64();
      entry.structuredCloneVersion = shEntry.stateData.formatVersion;
    }

    if (!(shEntry instanceof Ci.nsISHContainer)) {
      return entry;
    }

    if (shEntry.childCount > 0 && !shEntry.hasDynamicallyAddedChild()) {
      let children = [];
      for (let i = 0; i < shEntry.childCount; i++) {
        let child = shEntry.GetChildAt(i);

        if (child) {
          // Don't try to restore framesets containing wyciwyg URLs.
          // (cf. bug 424689 and bug 450595)
          if (child.URI.schemeIs("wyciwyg")) {
            children.length = 0;
            break;
          }

          children.push(this.serializeEntry(child));
        }
      }

      if (children.length) {
        entry.children = children;
      }
    }

    return entry;
  },

  /**
   * Restores session history data for a given docShell.
   *
   * @param docShell
   *        The docShell that owns the session history.
   * @param tabData
   *        The tabdata including all history entries.
   */
  restore: function (docShell, tabData) {
    let webNavigation = docShell.QueryInterface(Ci.nsIWebNavigation);
    let history = webNavigation.sessionHistory;
    if (history.count > 0) {
      history.PurgeHistory(history.count);
    }
    history.QueryInterface(Ci.nsISHistoryInternal);

    let idMap = { used: {} };
    let docIdentMap = {};
    for (let i = 0; i < tabData.entries.length; i++) {
      let entry = tabData.entries[i];
      //XXXzpao Wallpaper patch for bug 514751
      if (!entry.url)
        continue;
      let persist = "persist" in entry ? entry.persist : true;
      history.addEntry(this.deserializeEntry(entry, idMap, docIdentMap), persist);
    }

    // Select the right history entry.
    let index = tabData.index - 1;
    if (index < history.count && history.index != index) {
      history.getEntryAtIndex(index, true);
    }
  },

  /**
   * Expands serialized history data into a session-history-entry instance.
   *
   * @param entry
   *        Object containing serialized history data for a URL
   * @param idMap
   *        Hash for ensuring unique frame IDs
   * @param docIdentMap
   *        Hash to ensure reuse of BFCache entries
   * @returns nsISHEntry
   */
  deserializeEntry: function (entry, idMap, docIdentMap) {

    var shEntry = Cc["@mozilla.org/browser/session-history-entry;1"].
                  createInstance(Ci.nsISHEntry);

    shEntry.setURI(Utils.makeURI(entry.url, entry.charset));
    shEntry.setTitle(entry.title || entry.url);
    if (entry.subframe)
      shEntry.setIsSubFrame(entry.subframe || false);
    shEntry.loadType = Ci.nsIDocShellLoadInfo.loadHistory;
    if (entry.contentType)
      shEntry.contentType = entry.contentType;
    if (entry.referrer) {
      shEntry.referrerURI = Utils.makeURI(entry.referrer);
      shEntry.referrerPolicy = entry.referrerPolicy;
    }
    if (entry.originalURI) {
      shEntry.originalURI = Utils.makeURI(entry.originalURI);
    }
    if (entry.loadReplace) {
      shEntry.loadReplace = entry.loadReplace;
    }
    if (entry.isSrcdocEntry)
      shEntry.srcdocData = entry.srcdocData;
    if (entry.baseURI)
      shEntry.baseURI = Utils.makeURI(entry.baseURI);

    if (entry.cacheKey) {
      var cacheKey = Cc["@mozilla.org/supports-PRUint32;1"].
                     createInstance(Ci.nsISupportsPRUint32);
      cacheKey.data = entry.cacheKey;
      shEntry.cacheKey = cacheKey;
    }

    if (entry.ID) {
      // get a new unique ID for this frame (since the one from the last
      // start might already be in use)
      var id = idMap[entry.ID] || 0;
      if (!id) {
        for (id = Date.now(); id in idMap.used; id++);
        idMap[entry.ID] = id;
        idMap.used[id] = true;
      }
      shEntry.ID = id;
    }

    if (entry.docshellID)
      shEntry.docshellID = entry.docshellID;

    if (entry.structuredCloneState && entry.structuredCloneVersion) {
      shEntry.stateData =
        Cc["@mozilla.org/docshell/structured-clone-container;1"].
        createInstance(Ci.nsIStructuredCloneContainer);

      shEntry.stateData.initFromBase64(entry.structuredCloneState,
                                       entry.structuredCloneVersion);
    }

    if (entry.scrollRestorationIsManual) {
      shEntry.scrollRestorationIsManual = true;
    } else if (entry.scroll) {
      var scrollPos = (entry.scroll || "0,0").split(",");
      scrollPos = [parseInt(scrollPos[0]) || 0, parseInt(scrollPos[1]) || 0];
      shEntry.setScrollPosition(scrollPos[0], scrollPos[1]);
    }

    let childDocIdents = {};
    if (entry.docIdentifier) {
      // If we have a serialized document identifier, try to find an SHEntry
      // which matches that doc identifier and adopt that SHEntry's
      // BFCacheEntry.  If we don't find a match, insert shEntry as the match
      // for the document identifier.
      let matchingEntry = docIdentMap[entry.docIdentifier];
      if (!matchingEntry) {
        matchingEntry = {shEntry: shEntry, childDocIdents: childDocIdents};
        docIdentMap[entry.docIdentifier] = matchingEntry;
      }
      else {
        shEntry.adoptBFCacheEntry(matchingEntry.shEntry);
        childDocIdents = matchingEntry.childDocIdents;
      }
    }

    // The field entry.owner_b64 got renamed to entry.triggeringPricipal_b64 in
    // Bug 1286472. To remain backward compatible we still have to support that
    // field for a few cycles before we can remove it within Bug 1289785.
    if (entry.owner_b64) {
      entry.triggeringPricipal_b64 = entry.owner_b64;
      delete entry.owner_b64;
    }

    // Before introducing the concept of principalToInherit we only had
    // a triggeringPrincipal within every entry which basically is the
    // equivalent of the new principalToInherit. To avoid compatibility
    // issues, we first check if the entry has entries for
    // triggeringPrincipal_base64 and principalToInherit_base64. If not
    // we fall back to using the principalToInherit (which is stored
    // as triggeringPrincipal_b64) as the triggeringPrincipal and
    // the principalToInherit.
    // FF55 will remove the triggeringPrincipal_b64, see Bug 1301666.
    if (entry.triggeringPrincipal_base64 || entry.principalToInherit_base64) {
      if (entry.triggeringPrincipal_base64) {
        shEntry.triggeringPrincipal =
          Utils.deserializePrincipal(entry.triggeringPrincipal_base64);
      }
      if (entry.principalToInherit_base64) {
        shEntry.principalToInherit =
          Utils.deserializePrincipal(entry.principalToInherit_base64);
      }
    } else if (entry.triggeringPrincipal_b64) {
      shEntry.triggeringPrincipal = Utils.deserializePrincipal(entry.triggeringPrincipal_b64);
      shEntry.principalToInherit = shEntry.triggeringPrincipal;
    }

    if (entry.children && shEntry instanceof Ci.nsISHContainer) {
      for (var i = 0; i < entry.children.length; i++) {
        //XXXzpao Wallpaper patch for bug 514751
        if (!entry.children[i].url)
          continue;

        // We're getting sessionrestore.js files with a cycle in the
        // doc-identifier graph, likely due to bug 698656.  (That is, we have
        // an entry where doc identifier A is an ancestor of doc identifier B,
        // and another entry where doc identifier B is an ancestor of A.)
        //
        // If we were to respect these doc identifiers, we'd create a cycle in
        // the SHEntries themselves, which causes the docshell to loop forever
        // when it looks for the root SHEntry.
        //
        // So as a hack to fix this, we restrict the scope of a doc identifier
        // to be a node's siblings and cousins, and pass childDocIdents, not
        // aDocIdents, to _deserializeHistoryEntry.  That is, we say that two
        // SHEntries with the same doc identifier have the same document iff
        // they have the same parent or their parents have the same document.

        shEntry.AddChild(this.deserializeEntry(entry.children[i], idMap,
                                               childDocIdents), i);
      }
    }

    return shEntry;
  },

};