ClickHouse/src/Functions/MultiMatchAllIndicesImpl.h
Alexey Milovidov 8b4a6a2416 Remove cruft
2021-10-28 02:10:39 +03:00

119 lines
3.9 KiB
C++

#pragma once
#include <base/types.h>
#include <Columns/ColumnString.h>
#include <DataTypes/DataTypesNumber.h>
#include "Regexps.h"
#include "config_functions.h"
#include <Common/config.h>
#if USE_HYPERSCAN
# include <hs.h>
#else
# include "MatchImpl.h"
#endif
namespace DB
{
namespace ErrorCodes
{
extern const int HYPERSCAN_CANNOT_SCAN_TEXT;
extern const int CANNOT_ALLOCATE_MEMORY;
extern const int NOT_IMPLEMENTED;
extern const int TOO_MANY_BYTES;
}
template <typename Name, typename Type, bool MultiSearchDistance>
struct MultiMatchAllIndicesImpl
{
using ResultType = Type;
static constexpr bool is_using_hyperscan = true;
/// Variable for understanding, if we used offsets for the output, most
/// likely to determine whether the function returns ColumnVector of ColumnArray.
static constexpr bool is_column_array = true;
static constexpr auto name = Name::name;
static auto getReturnType()
{
return std::make_shared<DataTypeArray>(std::make_shared<DataTypeUInt64>());
}
static void vectorConstant(
const ColumnString::Chars & haystack_data,
const ColumnString::Offsets & haystack_offsets,
const std::vector<StringRef> & needles,
PaddedPODArray<Type> & res,
PaddedPODArray<UInt64> & offsets)
{
vectorConstant(haystack_data, haystack_offsets, needles, res, offsets, std::nullopt);
}
static void vectorConstant(
const ColumnString::Chars & haystack_data,
const ColumnString::Offsets & haystack_offsets,
const std::vector<StringRef> & needles,
PaddedPODArray<Type> & res,
PaddedPODArray<UInt64> & offsets,
[[maybe_unused]] std::optional<UInt32> edit_distance)
{
offsets.resize(haystack_offsets.size());
#if USE_HYPERSCAN
const auto & hyperscan_regex = MultiRegexps::get</*SaveIndices=*/true, MultiSearchDistance>(needles, edit_distance);
hs_scratch_t * scratch = nullptr;
hs_error_t err = hs_clone_scratch(hyperscan_regex->getScratch(), &scratch);
if (err != HS_SUCCESS)
throw Exception("Could not clone scratch space for hyperscan", ErrorCodes::CANNOT_ALLOCATE_MEMORY);
MultiRegexps::ScratchPtr smart_scratch(scratch);
auto on_match = [](unsigned int id,
unsigned long long /* from */, // NOLINT
unsigned long long /* to */, // NOLINT
unsigned int /* flags */,
void * context) -> int
{
static_cast<PaddedPODArray<Type>*>(context)->push_back(id);
return 0;
};
const size_t haystack_offsets_size = haystack_offsets.size();
UInt64 offset = 0;
for (size_t i = 0; i < haystack_offsets_size; ++i)
{
UInt64 length = haystack_offsets[i] - offset - 1;
/// Hyperscan restriction.
if (length > std::numeric_limits<UInt32>::max())
throw Exception("Too long string to search", ErrorCodes::TOO_MANY_BYTES);
/// Scan, check, update the offsets array and the offset of haystack.
err = hs_scan(
hyperscan_regex->getDB(),
reinterpret_cast<const char *>(haystack_data.data()) + offset,
length,
0,
smart_scratch.get(),
on_match,
&res);
if (err != HS_SUCCESS)
throw Exception("Failed to scan with hyperscan", ErrorCodes::HYPERSCAN_CANNOT_SCAN_TEXT);
offsets[i] = res.size();
offset = haystack_offsets[i];
}
#else
(void)haystack_data;
(void)haystack_offsets;
(void)needles;
(void)res;
(void)offsets;
throw Exception(
"multi-search all indices is not implemented when hyperscan is off (is it x86 processor?)",
ErrorCodes::NOT_IMPLEMENTED);
#endif // USE_HYPERSCAN
}
};
}