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
|
/* 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/. */
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
SessionStore: "resource:///modules/sessionstore/SessionStore.sys.mjs",
});
/**
* A module that enables async flushes. Updates from frame scripts are
* throttled to be sent only once per second. If an action wants a tab's latest
* state without waiting for a second then it can request an async flush and
* wait until the frame scripts reported back. At this point the parent has the
* latest data and the action can continue.
*/
export var TabStateFlusher = Object.freeze({
/**
* Requests an async flush for the given browser. Returns a promise that will
* resolve when we heard back from the content process and the parent has
* all the latest data.
*/
flush(browser) {
return TabStateFlusherInternal.flush(browser);
},
/**
* Requests an async flush for all browsers of a given window. Returns a Promise
* that will resolve when we've heard back from all browsers.
*/
flushWindow(window) {
return TabStateFlusherInternal.flushWindow(window);
},
/**
* Resolves the flush request with the given flush ID.
*
* @param browser (<xul:browser>)
* The browser for which the flush is being resolved.
* @param flushID (int)
* The ID of the flush that was sent to the browser.
* @param success (bool, optional)
* Whether or not the flush succeeded.
* @param message (string, optional)
* An error message that will be sent to the Console in the
* event that a flush failed.
*/
resolve(browser, flushID, success = true, message = "") {
TabStateFlusherInternal.resolve(browser, flushID, success, message);
},
/**
* Resolves all active flush requests for a given browser. This should be
* used when the content process crashed or the final update message was
* seen. In those cases we can't guarantee to ever hear back from the frame
* script so we just resolve all requests instead of discarding them.
*
* @param browser (<xul:browser>)
* The browser for which all flushes are being resolved.
* @param success (bool, optional)
* Whether or not the flushes succeeded.
* @param message (string, optional)
* An error message that will be sent to the Console in the
* event that the flushes failed.
*/
resolveAll(browser, success = true, message = "") {
TabStateFlusherInternal.resolveAll(browser, success, message);
},
});
var TabStateFlusherInternal = {
// Stores the last request ID.
_lastRequestID: 0,
// A map storing all active requests per browser. A request is a
// triple of a map containing all flush requests, a promise that
// resolve when a request for a browser is canceled, and the
// function to call to cancel a reqeust.
_requests: new WeakMap(),
initEntry(entry) {
entry.perBrowserRequests = new Map();
entry.cancelPromise = new Promise(resolve => {
entry.cancel = resolve;
}).then(result => {
TabStateFlusherInternal.initEntry(entry);
return result;
});
return entry;
},
/**
* Requests an async flush for the given browser. Returns a promise that will
* resolve when we heard back from the content process and the parent has
* all the latest data.
*/
flush(browser) {
let id = ++this._lastRequestID;
let nativePromise = Promise.resolve();
if (browser && browser.frameLoader) {
/*
Request native listener to flush the tabState.
Resolves when flush is complete.
*/
nativePromise = browser.frameLoader.requestTabStateFlush();
}
if (!Services.appinfo.sessionHistoryInParent) {
/*
In the event that we have to trigger a process switch and thus change
browser remoteness, session store needs to register and track the new
browser window loaded and to have message manager listener registered
** before ** TabStateFlusher send "SessionStore:flush" message. This fixes
the race where we send the message before the message listener is
registered for it.
*/
lazy.SessionStore.ensureInitialized(browser.ownerGlobal);
let mm = browser.messageManager;
mm.sendAsyncMessage("SessionStore:flush", {
id,
epoch: lazy.SessionStore.getCurrentEpoch(browser),
});
}
// Retrieve active requests for given browser.
let permanentKey = browser.permanentKey;
let request = this._requests.get(permanentKey);
if (!request) {
// If we don't have any requests for this browser, create a new
// entry for browser.
request = this.initEntry({});
this._requests.set(permanentKey, request);
}
// Non-SHIP flushes resolve this after the "SessionStore:update" message. We
// don't use that message for SHIP, so it's fine to resolve the request
// immediately after the native promise resolves, since SessionStore will
// have processed all updates from this browser by that point.
let requestPromise = Promise.resolve();
if (!Services.appinfo.sessionHistoryInParent) {
requestPromise = new Promise(resolve => {
// Store resolve() so that we can resolve the promise later.
request.perBrowserRequests.set(id, resolve);
});
}
return Promise.race([
nativePromise.then(_ => requestPromise),
request.cancelPromise,
]);
},
/**
* Requests an async flush for all non-lazy browsers of a given window.
* Returns a Promise that will resolve when we've heard back from all browsers.
*/
flushWindow(window) {
let promises = [];
for (let browser of window.gBrowser.browsers) {
if (window.gBrowser.getTabForBrowser(browser).linkedPanel) {
promises.push(this.flush(browser));
}
}
return Promise.all(promises);
},
/**
* Resolves the flush request with the given flush ID.
*
* @param browser (<xul:browser>)
* The browser for which the flush is being resolved.
* @param flushID (int)
* The ID of the flush that was sent to the browser.
* @param success (bool, optional)
* Whether or not the flush succeeded.
* @param message (string, optional)
* An error message that will be sent to the Console in the
* event that a flush failed.
*/
resolve(browser, flushID, success = true, message = "") {
// Nothing to do if there are no pending flushes for the given browser.
if (!this._requests.has(browser.permanentKey)) {
return;
}
// Retrieve active requests for given browser.
let { perBrowserRequests } = this._requests.get(browser.permanentKey);
if (!perBrowserRequests.has(flushID)) {
return;
}
if (!success) {
console.error("Failed to flush browser: ", message);
}
// Resolve the request with the given id.
let resolve = perBrowserRequests.get(flushID);
perBrowserRequests.delete(flushID);
resolve(success);
},
/**
* Resolves all active flush requests for a given browser. This should be
* used when the content process crashed or the final update message was
* seen. In those cases we can't guarantee to ever hear back from the frame
* script so we just resolve all requests instead of discarding them.
*
* @param browser (<xul:browser>)
* The browser for which all flushes are being resolved.
* @param success (bool, optional)
* Whether or not the flushes succeeded.
* @param message (string, optional)
* An error message that will be sent to the Console in the
* event that the flushes failed.
*/
resolveAll(browser, success = true, message = "") {
// Nothing to do if there are no pending flushes for the given browser.
if (!this._requests.has(browser.permanentKey)) {
return;
}
// Retrieve the cancel function for a given browser.
let { cancel } = this._requests.get(browser.permanentKey);
if (!success) {
console.error("Failed to flush browser: ", message);
}
// Resolve all requests.
cancel(success);
},
};
|
