summaryrefslogtreecommitdiffstats
path: root/toolkit/components/thumbnails/PageThumbs.worker.js
blob: eedf88130ed009d9b197b47086405ed9a6df83f9 (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
/* 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/. */

/**
 * A worker dedicated for the I/O component of PageThumbs storage.
 */

"use strict";

/* import-globals-from /toolkit/components/workerloader/require.js */
importScripts("resource://gre/modules/workers/require.js");

var PromiseWorker = require("resource://gre/modules/workers/PromiseWorker.js");

var worker = new PromiseWorker.AbstractWorker();
worker.dispatch = function (method, args = []) {
  return Agent[method](...args);
};
worker.postMessage = function (message, ...transfers) {
  self.postMessage(message, ...transfers);
};
worker.close = function () {
  self.close();
};

self.addEventListener("message", msg => worker.handleMessage(msg));
self.addEventListener("unhandledrejection", function (error) {
  throw error.reason;
});

var Agent = {
  // Checks if the specified file exists and has an age less than as
  // specifed (in seconds).
  async isFileRecent(path, maxAge) {
    try {
      let stat = await IOUtils.stat(path);
      let maxDate = new Date();
      maxDate.setSeconds(maxDate.getSeconds() - maxAge);
      return stat.lastModified > maxDate;
    } catch (ex) {
      if (!(ex instanceof DOMException)) {
        throw ex;
      }
      // file doesn't exist (or can't be stat'd) - must be stale.
      return false;
    }
  },

  async remove(path) {
    try {
      await IOUtils.remove(path);
      return true;
    } catch (e) {
      return false;
    }
  },

  async expireFilesInDirectory(path, filesToKeep, minChunkSize) {
    let entries = await this.getFileEntriesInDirectory(path, filesToKeep);
    let limit = Math.max(minChunkSize, Math.round(entries.length / 2));

    for (let entry of entries) {
      await this.remove(entry);

      // Check if we reached the limit of files to remove.
      if (--limit <= 0) {
        break;
      }
    }

    return true;
  },

  async getFileEntriesInDirectory(path, skipFiles) {
    let children = await IOUtils.getChildren(path);
    let skip = new Set(skipFiles);

    let entries = [];
    for (let entry of children) {
      let stat = await IOUtils.stat(entry);
      if (stat.type === "regular" && !skip.has(PathUtils.filename(entry))) {
        entries.push(entry);
      }
    }
    return entries;
  },

  async moveOrDeleteAllThumbnails(pathFrom, pathTo) {
    await IOUtils.makeDirectory(pathTo);
    if (pathFrom == pathTo) {
      return true;
    }
    let children = await IOUtils.getChildren(pathFrom);
    for (let entry of children) {
      let stat = await IOUtils.stat(entry);
      if (stat.type !== "regular") {
        continue;
      }

      let fileName = PathUtils.filename(entry);
      let from = PathUtils.join(pathFrom, fileName);
      let to = PathUtils.join(pathTo, fileName);

      try {
        await IOUtils.move(from, to, { noOverwrite: true });
      } catch (e) {
        await IOUtils.remove(from);
      }
    }

    try {
      await IOUtils.remove(pathFrom, { recursive: true });
    } catch (e) {
      // This could fail if there's something in
      // the folder we're not permitted to remove.
    }

    return true;
  },

  writeAtomic(path, buffer, options) {
    return IOUtils.write(path, buffer, options);
  },

  makeDir(path, options) {
    return IOUtils.makeDirectory(path, options);
  },

  copy(source, dest, options) {
    return IOUtils.copy(source, dest, options);
  },

  async wipe(path) {
    let children = await IOUtils.getChildren(path);
    try {
      await Promise.all(children.map(entry => IOUtils.remove(entry)));
    } catch (ex) {
      // If a file cannot be removed, we should still continue.
      // This can happen at least for any of the following reasons:
      // - access denied;
      // - file has been removed recently during a previous wipe
      //  and the file system has not flushed that yet (yes, this
      //  can happen under Windows);
      // - file has been removed by the user or another process.
    }
  },

  exists(path) {
    return IOUtils.exists(path);
  },
};