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-rw-r--r--tools/addon-sdk-1.12/lib/sdk/simple-storage.js237
1 files changed, 0 insertions, 237 deletions
diff --git a/tools/addon-sdk-1.12/lib/sdk/simple-storage.js b/tools/addon-sdk-1.12/lib/sdk/simple-storage.js
deleted file mode 100644
index 2b88cc1..0000000
--- a/tools/addon-sdk-1.12/lib/sdk/simple-storage.js
+++ /dev/null
@@ -1,237 +0,0 @@
-/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
- * vim:set ts=2 sw=2 sts=2 et filetype=javascript
- * 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";
-
-module.metadata = {
- "stability": "stable"
-};
-
-const { Cc, Ci } = require("chrome");
-const file = require("./io/file");
-const prefs = require("./preferences/service");
-const jpSelf = require("./self");
-const timer = require("./timers");
-const unload = require("./system/unload");
-const { emit, on, off } = require("./event/core");
-
-const WRITE_PERIOD_PREF = "extensions.addon-sdk.simple-storage.writePeriod";
-const WRITE_PERIOD_DEFAULT = 300000; // 5 minutes
-
-const QUOTA_PREF = "extensions.addon-sdk.simple-storage.quota";
-const QUOTA_DEFAULT = 5242880; // 5 MiB
-
-const JETPACK_DIR_BASENAME = "jetpack";
-
-Object.defineProperties(exports, {
- storage: {
- enumerable: true,
- get: function() { return manager.root; },
- set: function(value) { manager.root = value; }
- },
- quotaUsage: {
- get: function() { return manager.quotaUsage; }
- }
-});
-
-// A generic JSON store backed by a file on disk. This should be isolated
-// enough to move to its own module if need be...
-function JsonStore(options) {
- this.filename = options.filename;
- this.quota = options.quota;
- this.writePeriod = options.writePeriod;
- this.onOverQuota = options.onOverQuota;
- this.onWrite = options.onWrite;
-
- unload.ensure(this);
-
- this.writeTimer = timer.setInterval(this.write.bind(this),
- this.writePeriod);
-}
-
-JsonStore.prototype = {
- // The store's root.
- get root() {
- return this.isRootInited ? this._root : {};
- },
-
- // Performs some type checking.
- set root(val) {
- let types = ["array", "boolean", "null", "number", "object", "string"];
- if (types.indexOf(typeof(val)) < 0) {
- throw new Error("storage must be one of the following types: " +
- types.join(", "));
- }
- this._root = val;
- return val;
- },
-
- // True if the root has ever been set (either via the root setter or by the
- // backing file's having been read).
- get isRootInited() {
- return this._root !== undefined;
- },
-
- // Percentage of quota used, as a number [0, Inf). > 1 implies over quota.
- // Undefined if there is no quota.
- get quotaUsage() {
- return this.quota > 0 ?
- JSON.stringify(this.root).length / this.quota :
- undefined;
- },
-
- // Removes the backing file and all empty subdirectories.
- purge: function JsonStore_purge() {
- try {
- // This'll throw if the file doesn't exist.
- file.remove(this.filename);
- let parentPath = this.filename;
- do {
- parentPath = file.dirname(parentPath);
- // This'll throw if the dir isn't empty.
- file.rmdir(parentPath);
- } while (file.basename(parentPath) !== JETPACK_DIR_BASENAME);
- }
- catch (err) {}
- },
-
- // Initializes the root by reading the backing file.
- read: function JsonStore_read() {
- try {
- let str = file.read(this.filename);
-
- // Ideally we'd log the parse error with console.error(), but logged
- // errors cause tests to fail. Supporting "known" errors in the test
- // harness appears to be non-trivial. Maybe later.
- this.root = JSON.parse(str);
- }
- catch (err) {
- this.root = {};
- }
- },
-
- // If the store is under quota, writes the root to the backing file.
- // Otherwise quota observers are notified and nothing is written.
- write: function JsonStore_write() {
- if (this.quotaUsage > 1)
- this.onOverQuota(this);
- else
- this._write();
- },
-
- // Cleans up on unload. If unloading because of uninstall, the store is
- // purged; otherwise it's written.
- unload: function JsonStore_unload(reason) {
- timer.clearInterval(this.writeTimer);
- this.writeTimer = null;
-
- if (reason === "uninstall")
- this.purge();
- else
- this._write();
- },
-
- // True if the root is an empty object.
- get _isEmpty() {
- if (this.root && typeof(this.root) === "object") {
- let empty = true;
- for (let key in this.root) {
- empty = false;
- break;
- }
- return empty;
- }
- return false;
- },
-
- // Writes the root to the backing file, notifying write observers when
- // complete. If the store is over quota or if it's empty and the store has
- // never been written, nothing is written and write observers aren't notified.
- _write: function JsonStore__write() {
- // Don't write if the root is uninitialized or if the store is empty and the
- // backing file doesn't yet exist.
- if (!this.isRootInited || (this._isEmpty && !file.exists(this.filename)))
- return;
-
- // If the store is over quota, don't write. The current under-quota state
- // should persist.
- if (this.quotaUsage > 1)
- return;
-
- // Finally, write.
- let stream = file.open(this.filename, "w");
- try {
- stream.writeAsync(JSON.stringify(this.root), function writeAsync(err) {
- if (err)
- console.error("Error writing simple storage file: " + this.filename);
- else if (this.onWrite)
- this.onWrite(this);
- }.bind(this));
- }
- catch (err) {
- // writeAsync closes the stream after it's done, so only close on error.
- stream.close();
- }
- }
-};
-
-
-// This manages a JsonStore singleton and tailors its use to simple storage.
-// The root of the JsonStore is lazy-loaded: The backing file is only read the
-// first time the root's gotten.
-let manager = ({
- jsonStore: null,
-
- // The filename of the store, based on the profile dir and extension ID.
- get filename() {
- let storeFile = Cc["@mozilla.org/file/directory_service;1"].
- getService(Ci.nsIProperties).
- get("ProfD", Ci.nsIFile);
- storeFile.append(JETPACK_DIR_BASENAME);
- storeFile.append(jpSelf.id);
- storeFile.append("simple-storage");
- file.mkpath(storeFile.path);
- storeFile.append("store.json");
- return storeFile.path;
- },
-
- get quotaUsage() {
- return this.jsonStore.quotaUsage;
- },
-
- get root() {
- if (!this.jsonStore.isRootInited)
- this.jsonStore.read();
- return this.jsonStore.root;
- },
-
- set root(val) {
- return this.jsonStore.root = val;
- },
-
- unload: function manager_unload() {
- off(this);
- },
-
- new: function manager_constructor() {
- let manager = Object.create(this);
- unload.ensure(manager);
-
- manager.jsonStore = new JsonStore({
- filename: manager.filename,
- writePeriod: prefs.get(WRITE_PERIOD_PREF, WRITE_PERIOD_DEFAULT),
- quota: prefs.get(QUOTA_PREF, QUOTA_DEFAULT),
- onOverQuota: emit.bind(null, exports, "OverQuota")
- });
-
- return manager;
- }
-}).new();
-
-exports.on = on.bind(null, exports);
-exports.removeListener = function(type, listener) {
- off(exports, type, listener);
-};