summaryrefslogtreecommitdiffstats
path: root/toolkit/mozapps/extensions/ChromeManifestParser.jsm
blob: 63f1db785aaa5b95b707cd670b310d6b10032de8 (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
/* 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 = ["ChromeManifestParser"];

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

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

const MSG_JAR_FLUSH = "AddonJarFlush";


/**
 * Sends local and remote notifications to flush a JAR file cache entry
 *
 * @param aJarFile
 *        The ZIP/XPI/JAR file as a nsIFile
 */
function flushJarCache(aJarFile) {
  Services.obs.notifyObservers(aJarFile, "flush-cache-entry", null);
  Cc["@mozilla.org/globalmessagemanager;1"].getService(Ci.nsIMessageBroadcaster)
    .broadcastAsyncMessage(MSG_JAR_FLUSH, aJarFile.path);
}


/**
 * Parses chrome manifest files.
 */
this.ChromeManifestParser = {

  /**
   * Reads and parses a chrome manifest file located at a specified URI, and all
   * secondary manifests it references.
   *
   * @param  aURI
   *         A nsIURI pointing to a chrome manifest.
   *         Typically a file: or jar: URI.
   * @return Array of objects describing each manifest instruction, in the form:
   *         { type: instruction-type, baseURI: string-uri, args: [arguments] }
   **/
  parseSync: function(aURI) {
    function parseLine(aLine) {
      let line = aLine.trim();
      if (line.length == 0 || line.charAt(0) == '#')
        return;
      let tokens = line.split(/\s+/);
      let type = tokens.shift();
      if (type == "manifest") {
        let uri = NetUtil.newURI(tokens.shift(), null, aURI);
        data = data.concat(this.parseSync(uri));
      } else {
        data.push({type: type, baseURI: baseURI, args: tokens});
      }
    }

    let contents = "";
    try {
      if (aURI.scheme == "jar")
        contents = this._readFromJar(aURI);
      else
        contents = this._readFromFile(aURI);
    } catch (e) {
      // Silently fail.
    }

    if (!contents)
      return [];

    let baseURI = NetUtil.newURI(".", null, aURI).spec;

    let data = [];
    let lines = contents.split("\n");
    lines.forEach(parseLine.bind(this));
    return data;
  },

  _readFromJar: function(aURI) {
    let data = "";
    let entries = [];
    let readers = [];

    try {
      // Deconstrict URI, which can be nested jar: URIs.
      let uri = aURI.clone();
      while (uri instanceof Ci.nsIJARURI) {
        entries.push(uri.JAREntry);
        uri = uri.JARFile;
      }

      // Open the base jar.
      let reader = Cc["@mozilla.org/libjar/zip-reader;1"].
                   createInstance(Ci.nsIZipReader);
      reader.open(uri.QueryInterface(Ci.nsIFileURL).file);
      readers.push(reader);

      // Open the nested jars.
      for (let i = entries.length - 1; i > 0; i--) {
        let innerReader = Cc["@mozilla.org/libjar/zip-reader;1"].
                          createInstance(Ci.nsIZipReader);
        innerReader.openInner(reader, entries[i]);
        readers.push(innerReader);
        reader = innerReader;
      }

      // First entry is the actual file we want to read.
      let zis = reader.getInputStream(entries[0]);
      data = NetUtil.readInputStreamToString(zis, zis.available());
    }
    finally {
      // Close readers in reverse order.
      for (let i = readers.length - 1; i >= 0; i--) {
        readers[i].close();
        flushJarCache(readers[i].file);
      }
    }

    return data;
  },

  _readFromFile: function(aURI) {
    let file = aURI.QueryInterface(Ci.nsIFileURL).file;
    if (!file.exists() || !file.isFile())
      return "";

    let data = "";
    let fis = Cc["@mozilla.org/network/file-input-stream;1"].
              createInstance(Ci.nsIFileInputStream);
    try {
      fis.init(file, -1, -1, false);
      data = NetUtil.readInputStreamToString(fis, fis.available());
    } finally {
      fis.close();
    }
    return data;
  },

  /**
  * Detects if there were any instructions of a specified type in a given
  * chrome manifest.
  *
  * @param  aManifest
  *         Manifest data, as returned by ChromeManifestParser.parseSync().
  * @param  aType
  *         Instruction type to filter by.
  * @return True if any matching instructions were found in the manifest.
  */
  hasType: function(aManifest, aType) {
    return aManifest.some(entry => entry.type == aType);
  }
};