summaryrefslogtreecommitdiff
path: root/chromium/third_party/blink/renderer/modules/filesystem/dom_file_path.cc
blob: d1ca3514469ca70338fb6ba0be46da7171d01814 (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
/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "third_party/blink/renderer/modules/filesystem/dom_file_path.h"

#include "third_party/blink/renderer/platform/wtf/text/cstring.h"
#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"

namespace blink {

const char DOMFilePath::kSeparator = '/';
const char DOMFilePath::kRoot[] = "/";

String DOMFilePath::Append(const String& base, const String& components) {
  return EnsureDirectoryPath(base) + components;
}

String DOMFilePath::EnsureDirectoryPath(const String& path) {
  if (!DOMFilePath::EndsWithSeparator(path))
    return path + DOMFilePath::kSeparator;
  return path;
}

String DOMFilePath::GetName(const String& path) {
  int index = path.ReverseFind(DOMFilePath::kSeparator);
  if (index != -1)
    return path.Substring(index + 1);
  return path;
}

String DOMFilePath::GetDirectory(const String& path) {
  int index = path.ReverseFind(DOMFilePath::kSeparator);
  if (!index)
    return DOMFilePath::kRoot;
  if (index != -1)
    return path.Substring(0, index);
  return ".";
}

bool DOMFilePath::IsParentOf(const String& parent, const String& may_be_child) {
  DCHECK(DOMFilePath::IsAbsolute(parent));
  DCHECK(DOMFilePath::IsAbsolute(may_be_child));
  if (parent == DOMFilePath::kRoot && may_be_child != DOMFilePath::kRoot)
    return true;
  if (parent.length() >= may_be_child.length() ||
      !may_be_child.StartsWithIgnoringCase(parent))
    return false;
  if (may_be_child[parent.length()] != DOMFilePath::kSeparator)
    return false;
  return true;
}

String DOMFilePath::RemoveExtraParentReferences(const String& path) {
  DCHECK(DOMFilePath::IsAbsolute(path));
  Vector<String> components;
  Vector<String> canonicalized;
  path.Split(DOMFilePath::kSeparator, components);
  for (const auto& component : components) {
    if (component == ".")
      continue;
    if (component == "..") {
      if (canonicalized.size() > 0)
        canonicalized.pop_back();
      continue;
    }
    canonicalized.push_back(component);
  }
  if (canonicalized.IsEmpty())
    return DOMFilePath::kRoot;
  StringBuilder result;
  for (const auto& component : canonicalized) {
    result.Append(DOMFilePath::kSeparator);
    result.Append(component);
  }
  return result.ToString();
}

bool DOMFilePath::IsValidPath(const String& path) {
  if (path.IsEmpty() || path == DOMFilePath::kRoot)
    return true;

  // Embedded NULs are not allowed.
  if (path.find(static_cast<UChar>(0)) != WTF::kNotFound)
    return false;

  // While not [yet] restricted by the spec, '\\' complicates implementation for
  // Chromium.
  if (path.find('\\') != WTF::kNotFound)
    return false;

  // This method is only called on fully-evaluated absolute paths. Any sign of
  // ".." or "." is likely an attempt to break out of the sandbox.
  Vector<String> components;
  path.Split(DOMFilePath::kSeparator, components);
  return std::none_of(components.begin(), components.end(),
                      [](const String& component) {
                        return component == "." || component == "..";
                      });
}

bool DOMFilePath::IsValidName(const String& name) {
  if (name.IsEmpty())
    return true;
  // '/' is not allowed in name.
  if (name.Contains('/'))
    return false;
  return IsValidPath(name);
}

}  // namespace blink