ClickHouse/dbms/src/Common/Collator.cpp
alexey-milovidov 35abae95c8 Allow to disable ICU (#711)
* Allow to disable ICU [#CLICKHOUSE-2].

* Addition to prev. revision [#CLICKHOUSE-2].

* Addition to prev. revision [#CLICKHOUSE-2].

* Addition to prev. revision [#CLICKHOUSE-2].
2017-04-19 04:06:29 +03:00

84 lines
2.0 KiB
C++

#include <Common/Collator.h>
#include <Common/config.h>
#if USE_ICU
#pragma GCC diagnostic push
#ifdef __APPLE__
#pragma GCC diagnostic ignored "-Wold-style-cast"
#endif
#include <unicode/ucol.h>
#pragma GCC diagnostic pop
#else
#pragma GCC diagnostic ignored "-Wunused-private-field"
#endif
#include <Common/Exception.h>
#include <IO/WriteHelpers.h>
#include <Poco/String.h>
namespace DB
{
namespace ErrorCodes
{
extern const int UNSUPPORTED_COLLATION_LOCALE;
extern const int COLLATION_COMPARISON_FAILED;
extern const int SUPPORT_IS_DISABLED;
}
}
Collator::Collator(const std::string & locale_) : locale(Poco::toLower(locale_))
{
#if USE_ICU
UErrorCode status = U_ZERO_ERROR;
collator = ucol_open(locale.c_str(), &status);
if (status != U_ZERO_ERROR)
{
ucol_close(collator);
throw DB::Exception("Unsupported collation locale: " + locale, DB::ErrorCodes::UNSUPPORTED_COLLATION_LOCALE);
}
#else
throw DB::Exception("Collations support is disabled, because ClickHouse was built without ICU library", DB::ErrorCodes::SUPPORT_IS_DISABLED);
#endif
}
Collator::~Collator()
{
#if USE_ICU
ucol_close(collator);
#endif
}
int Collator::compare(const char * str1, size_t length1, const char * str2, size_t length2) const
{
#if USE_ICU
UCharIterator iter1, iter2;
uiter_setUTF8(&iter1, str1, length1);
uiter_setUTF8(&iter2, str2, length2);
UErrorCode status = U_ZERO_ERROR;
UCollationResult compare_result = ucol_strcollIter(collator, &iter1, &iter2, &status);
if (status != U_ZERO_ERROR)
throw DB::Exception("ICU collation comparison failed with error code: " + DB::toString<int>(status),
DB::ErrorCodes::COLLATION_COMPARISON_FAILED);
/** Values of enum UCollationResult are equals to what exactly we need:
* UCOL_EQUAL = 0
* UCOL_GREATER = 1
* UCOL_LESS = -1
*/
return compare_result;
#else
return 0;
#endif
}
const std::string & Collator::getLocale() const
{
return locale;
}