Separate out some more ICU from base and into base/i18n....

base/file_util_icu.cc

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// File utilities that use the ICU library go in this file.  Functions using ICU
-// are separated from the other functions to prevent ICU being pulled in by the
-// linker if there is a false dependency.
-//
-// (The VS2005 linker finds such a false dependency and adds ~300K of ICU to
-// chrome.exe if this code lives in file_util.cc, even though none of this code
-// is called.)
-
-#include "base/file_util.h"
-
-#include "base/singleton.h"
-#include "base/string_util.h"
-#include "unicode/uniset.h"
-
-namespace {
-class IllegalCharacters {
- public:
-  bool contains(UChar32 ucs4) {
-    return !!set->contains(ucs4);
-  }
-
-  bool containsNone(const string16 &s) {
-    return !!set->containsNone(icu::UnicodeString(s.c_str(), s.size()));
-  }
-
- private:
-  friend class Singleton<IllegalCharacters>;
-  friend struct DefaultSingletonTraits<IllegalCharacters>;
-
-  IllegalCharacters();
-  ~IllegalCharacters() { }
-
-  scoped_ptr<icu::UnicodeSet> set;
-
-  DISALLOW_COPY_AND_ASSIGN(IllegalCharacters);
-};
-
-IllegalCharacters::IllegalCharacters() {
-  UErrorCode status = U_ZERO_ERROR;
-  // Control characters, formatting characters, non-characters, and
-  // some printable ASCII characters regarded as dangerous ('"*/:<>?\\').
-  // See  http://blogs.msdn.com/michkap/archive/2006/11/03/941420.aspx
-  // and http://msdn2.microsoft.com/en-us/library/Aa365247.aspx
-  // TODO(jungshik): Revisit the set. ZWJ and ZWNJ are excluded because they
-  // are legitimate in Arabic and some S/SE Asian scripts. However, when used
-  // elsewhere, they can be confusing/problematic.
-  // Also, consider wrapping the set with our Singleton class to create and
-  // freeze it only once. Note that there's a trade-off between memory and
-  // speed.
-#if defined(WCHAR_T_IS_UTF16)
-  set.reset(new icu::UnicodeSet(icu::UnicodeString(
-      L"[[\"*/:<>?\\\\|][:Cc:][:Cf:] - [\u200c\u200d]]"), status));
-#else
-  set.reset(new icu::UnicodeSet(UNICODE_STRING_SIMPLE(
-      "[[\"*/:<>?\\\\|][:Cc:][:Cf:] - [\\u200c\\u200d]]").unescape(),
-      status));
-#endif
-  DCHECK(U_SUCCESS(status));
-  // Add non-characters. If this becomes a performance bottleneck by
-  // any chance, do not add these to |set| and change IsFilenameLegal()
-  // to check |ucs4 & 0xFFFEu == 0xFFFEu|, in addiition to calling
-  // containsNone().
-  set->add(0xFDD0, 0xFDEF);
-  for (int i = 0; i <= 0x10; ++i) {
-    int plane_base = 0x10000 * i;
-    set->add(plane_base + 0xFFFE, plane_base + 0xFFFF);
-  }
-  set->freeze();
-}
-
-}  // namespace
-
-namespace file_util {
-
-bool IsFilenameLegal(const string16& file_name) {
-  return Singleton<IllegalCharacters>()->containsNone(file_name);
-}
-
-void ReplaceIllegalCharacters(std::wstring* file_name, int replace_char) {
-  DCHECK(file_name);
-
-  DCHECK(!(Singleton<IllegalCharacters>()->contains(replace_char)) &&
-         replace_char < 0x10000);
-
-  // Remove leading and trailing whitespace.
-  TrimWhitespace(*file_name, TRIM_ALL, file_name);
-
-  if (IsFilenameLegal(WideToUTF16(*file_name)))
-    return;
-
-  std::wstring::size_type i = 0;
-  std::wstring::size_type length = file_name->size();
-  const wchar_t* wstr = file_name->data();
-#if defined(WCHAR_T_IS_UTF16)
-  // Using |span| method of UnicodeSet might speed things up a bit, but
-  // it's not likely to matter here.
-  std::wstring temp;
-  temp.reserve(length);
-  while (i < length) {
-    UChar32 ucs4;
-    std::wstring::size_type prev = i;
-    U16_NEXT(wstr, i, length, ucs4);
-    if (Singleton<IllegalCharacters>()->contains(ucs4)) {
-      temp.push_back(replace_char);
-    } else if (ucs4 < 0x10000) {
-      temp.push_back(ucs4);
-    } else {
-      temp.push_back(wstr[prev]);
-      temp.push_back(wstr[prev + 1]);
-    }
-  }
-  file_name->swap(temp);
-#elif defined(WCHAR_T_IS_UTF32)
-  while (i < length) {
-    if (Singleton<IllegalCharacters>()->contains(wstr[i])) {
-      (*file_name)[i] = replace_char;
-    }
-    ++i;
-  }
-#else
-#error wchar_t* should be either UTF-16 or UTF-32
-#endif
-}
-
-}  // namespace