third_party/WebKit/Source/modules/filesystem/DirectoryReader.cpp

   1 /*
   2  * Copyright (C) 2010 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "config.h"
  32 #include "modules/filesystem/DirectoryReader.h"
  33
  34 #include "core/fileapi/FileError.h"
  35 #include "modules/filesystem/EntriesCallback.h"
  36 #include "modules/filesystem/Entry.h"
  37 #include "modules/filesystem/ErrorCallback.h"
  38
  39 namespace blink {
  40
  41 class DirectoryReader::EntriesCallbackHelper final : public EntriesCallback {
  42 public:
  43     explicit EntriesCallbackHelper(DirectoryReader* reader)
  44         : m_reader(reader)
  45     {
  46     }
  47
  48     void handleEvent(const EntryHeapVector& entries) override
  49     {
  50         m_reader->addEntries(entries);
  51     }
  52
  53     DEFINE_INLINE_VIRTUAL_TRACE()
  54     {
  55         visitor->trace(m_reader);
  56         EntriesCallback::trace(visitor);
  57     }
  58
  59 private:
  60     // FIXME: This Member keeps the reader alive until all of the readDirectory results are received. crbug.com/350285
  61     Member<DirectoryReader> m_reader;
  62 };
  63
  64 class DirectoryReader::ErrorCallbackHelper final : public ErrorCallback {
  65 public:
  66     explicit ErrorCallbackHelper(DirectoryReader* reader)
  67         : m_reader(reader)
  68     {
  69     }
  70
  71     void handleEvent(FileError* error) override
  72     {
  73         m_reader->onError(error);
  74     }
  75
  76     DEFINE_INLINE_VIRTUAL_TRACE()
  77     {
  78         visitor->trace(m_reader);
  79         ErrorCallback::trace(visitor);
  80     }
  81
  82 private:
  83     Member<DirectoryReader> m_reader;
  84 };
  85
  86 DirectoryReader::DirectoryReader(DOMFileSystemBase* fileSystem, const String& fullPath)
  87     : DirectoryReaderBase(fileSystem, fullPath)
  88     , m_isReading(false)
  89 {
  90 }
  91
  92 DirectoryReader::~DirectoryReader()
  93 {
  94 }
  95
  96 void DirectoryReader::readEntries(EntriesCallback* entriesCallback, ErrorCallback* errorCallback)
  97 {
  98     if (!m_isReading) {
  99         m_isReading = true;
 100         filesystem()->readDirectory(this, m_fullPath, new EntriesCallbackHelper(this), new ErrorCallbackHelper(this));
 101     }
 102
 103     if (m_error) {
 104         filesystem()->scheduleCallback(errorCallback, m_error);
 105         return;
 106     }
 107
 108     if (m_entriesCallback) {
 109         // Non-null m_entriesCallback means multiple readEntries() calls are made concurrently. We don't allow doing it.
 110         filesystem()->scheduleCallback(errorCallback, FileError::create(FileError::INVALID_STATE_ERR));
 111         return;
 112     }
 113
 114     if (!m_hasMoreEntries || !m_entries.isEmpty()) {
 115         filesystem()->scheduleCallback(entriesCallback, m_entries);
 116         m_entries.clear();
 117         return;
 118     }
 119
 120     m_entriesCallback = entriesCallback;
 121     m_errorCallback = errorCallback;
 122 }
 123
 124 void DirectoryReader::addEntries(const EntryHeapVector& entries)
 125 {
 126     m_entries.appendVector(entries);
 127     m_errorCallback = nullptr;
 128     if (m_entriesCallback) {
 129         EntriesCallback* entriesCallback = m_entriesCallback.release();
 130         EntryHeapVector entries;
 131         entries.swap(m_entries);
 132         entriesCallback->handleEvent(entries);
 133     }
 134 }
 135
 136 void DirectoryReader::onError(FileError* error)
 137 {
 138     m_error = error;
 139     m_entriesCallback = nullptr;
 140     if (m_errorCallback) {
 141         ErrorCallback* errorCallback = m_errorCallback.release();
 142         errorCallback->handleEvent(error);
 143     }
 144 }
 145
 146 DEFINE_TRACE(DirectoryReader)
 147 {
 148     visitor->trace(m_entries);
 149     visitor->trace(m_error);
 150     visitor->trace(m_entriesCallback);
 151     visitor->trace(m_errorCallback);
 152     DirectoryReaderBase::trace(visitor);
 153 }
 154
 155 }