shaka-packager/base/i18n/string_search.cc

81 lines
2.7 KiB
C++

// Copyright (c) 2011 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.
#include "base/i18n/string_search.h"
#include "base/logging.h"
#include "third_party/icu/source/i18n/unicode/usearch.h"
namespace base {
namespace i18n {
FixedPatternStringSearchIgnoringCaseAndAccents::
FixedPatternStringSearchIgnoringCaseAndAccents(const string16& find_this)
: find_this_(find_this) {
// usearch_open requires a valid string argument to be searched, even if we
// want to set it by usearch_setText afterwards. So, supplying a dummy text.
const string16& dummy = find_this_;
UErrorCode status = U_ZERO_ERROR;
search_ = usearch_open(find_this_.data(), find_this_.size(),
dummy.data(), dummy.size(),
uloc_getDefault(),
NULL, // breakiter
&status);
if (U_SUCCESS(status)) {
UCollator* collator = usearch_getCollator(search_);
ucol_setStrength(collator, UCOL_PRIMARY);
usearch_reset(search_);
}
}
FixedPatternStringSearchIgnoringCaseAndAccents::
~FixedPatternStringSearchIgnoringCaseAndAccents() {
if (search_)
usearch_close(search_);
}
bool FixedPatternStringSearchIgnoringCaseAndAccents::Search(
const string16& in_this, size_t* match_index, size_t* match_length) {
UErrorCode status = U_ZERO_ERROR;
usearch_setText(search_, in_this.data(), in_this.size(), &status);
// Default to basic substring search if usearch fails. According to
// http://icu-project.org/apiref/icu4c/usearch_8h.html, usearch_open will fail
// if either |find_this| or |in_this| are empty. In either case basic
// substring search will give the correct return value.
if (!U_SUCCESS(status)) {
size_t index = in_this.find(find_this_);
if (index == string16::npos) {
return false;
} else {
if (match_index)
*match_index = index;
if (match_length)
*match_length = find_this_.size();
return true;
}
}
int32_t index = usearch_first(search_, &status);
if (!U_SUCCESS(status) || index == USEARCH_DONE)
return false;
if (match_index)
*match_index = static_cast<size_t>(index);
if (match_length)
*match_length = static_cast<size_t>(usearch_getMatchedLength(search_));
return true;
}
bool StringSearchIgnoringCaseAndAccents(const string16& find_this,
const string16& in_this,
size_t* match_index,
size_t* match_length) {
return FixedPatternStringSearchIgnoringCaseAndAccents(find_this).Search(
in_this, match_index, match_length);
}
} // namespace i18n
} // namespace base