Introduce regexpQuoteMeta function to properly handle regexp special chars in TRIM #3714

This commit is contained in:
Ivan Blinkov 2018-12-13 15:58:00 +03:00
parent 034265f044
commit 180311b42b
6 changed files with 138 additions and 2 deletions

View File

@ -0,0 +1,112 @@
#include <Common/config.h>
#include <Columns/ColumnConst.h>
#include <Columns/ColumnString.h>
#include <DataTypes/DataTypeString.h>
#include <Functions/FunctionFactory.h>
#include <Functions/FunctionHelpers.h>
#include <Functions/GatherUtils/Algorithms.h>
#include <IO/WriteHelpers.h>
#include <re2/re2.h>
#include <re2/stringpiece.h>
#if USE_RE2_ST
#include <re2_st/re2.h> // Y_IGNORE
#else
#define re2_st re2
#endif
namespace DB
{
using namespace GatherUtils;
namespace ErrorCodes
{
extern const int ILLEGAL_COLUMN;
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
}
class FunctionRegexpQuoteMeta : public IFunction
{
public:
static constexpr auto name = "regexpQuoteMeta";
static FunctionPtr create(const Context &)
{
return std::make_shared<FunctionRegexpQuoteMeta>();
}
String getName() const override
{
return name;
}
size_t getNumberOfArguments() const override
{
return 1;
}
bool useDefaultImplementationForConstants() const override
{
return true;
}
DataTypePtr getReturnTypeImpl(const ColumnsWithTypeAndName & arguments) const override
{
if (!WhichDataType(arguments[0].type).isString())
throw Exception(
"Illegal type " + arguments[0].type->getName() + " of 1 argument of function " + getName() + ". Must be String.",
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return std::make_shared<DataTypeString>();
}
void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t input_rows_count) override
{
const ColumnPtr column_string = block.getByPosition(arguments[0]).column;
const ColumnString * input = checkAndGetColumn<ColumnString>(column_string.get());
if (!input)
throw Exception(
"Illegal column " + block.getByPosition(arguments[0]).column->getName() + " of first argument of function " + getName(),
ErrorCodes::ILLEGAL_COLUMN);
auto dst_column = ColumnString::create();
auto & dst_data = dst_column->getChars();
auto & dst_offsets = dst_column->getOffsets();
dst_data.resize(input->getChars().size() * input->size());
dst_offsets.resize(input_rows_count);
const ColumnString::Offsets & src_offsets = input->getOffsets();
auto source = reinterpret_cast<const char *>(input->getChars().data());
auto dst = reinterpret_cast<char *>(dst_data.data());
auto dst_pos = dst;
size_t src_offset_prev = 0;
for (size_t row = 0; row < input_rows_count; ++row)
{
size_t srclen = src_offsets[row] - src_offset_prev - 1;
re2_st::StringPiece unquoted(source, srclen);
const auto & quoted = re2_st::RE2::QuoteMeta(unquoted);
std::memcpy(dst_pos, quoted.data(), quoted.size());
source += srclen + 1;
dst_pos += quoted.size() + 1;
dst_offsets[row] = dst_pos - dst;
src_offset_prev = src_offsets[row];
}
dst_data.resize(dst_pos - dst);
block.getByPosition(result).column = std::move(dst_column);
}
};
}

View File

@ -0,0 +1,10 @@
#include <Functions/FunctionRegexpQuoteMeta.h>
#include <Functions/FunctionFactory.h>
namespace DB
{
void registerFunctionRegexpQuoteMeta(FunctionFactory & factory)
{
factory.registerFunction<FunctionRegexpQuoteMeta>();
}
}

View File

@ -21,6 +21,7 @@ void registerFunctionSubstringUTF8(FunctionFactory &);
void registerFunctionAppendTrailingCharIfAbsent(FunctionFactory &);
void registerFunctionStartsWith(FunctionFactory &);
void registerFunctionEndsWith(FunctionFactory &);
void registerFunctionRegexpQuoteMeta(FunctionFactory &);
#if USE_BASE64
void registerFunctionBase64Encode(FunctionFactory &);
@ -46,6 +47,7 @@ void registerFunctionsString(FunctionFactory & factory)
registerFunctionAppendTrailingCharIfAbsent(factory);
registerFunctionStartsWith(factory);
registerFunctionEndsWith(factory);
registerFunctionRegexpQuoteMeta(factory);
#if USE_BASE64
registerFunctionBase64Encode(factory);
registerFunctionBase64Decode(factory);

View File

@ -444,10 +444,20 @@ bool ParserTrimExpression::parseImpl(Pos & pos, ASTPtr & node, Expected & expect
if (char_override)
{
if (!ParserExpression().parse(pos, to_remove, expected)) /// TODO: wrap in RE2::QuoteMeta call
if (!ParserExpression().parse(pos, to_remove, expected))
return false;
if (!ParserKeyword("FROM").ignore(pos, expected))
return false;
auto quote_meta_func_node = std::make_shared<ASTFunction>();
auto quote_meta_list_args = std::make_shared<ASTExpressionList>();
quote_meta_list_args->children = {to_remove};
quote_meta_func_node->name = "regexpQuoteMeta";
quote_meta_func_node->arguments = std::move(quote_meta_list_args);
quote_meta_func_node->children.push_back(quote_meta_func_node->arguments);
to_remove = std::move(quote_meta_func_node);
}
}
@ -463,9 +473,9 @@ bool ParserTrimExpression::parseImpl(Pos & pos, ASTPtr & node, Expected & expect
/// Convert to regexp replace function call
auto pattern_func_node = std::make_shared<ASTFunction>();
if (char_override)
{
auto pattern_func_node = std::make_shared<ASTFunction>();
auto pattern_list_args = std::make_shared<ASTExpressionList>();
if (trim_left && trim_right)
{

View File

@ -17,3 +17,4 @@ foo
xxfoo
fooabba
fooabbafoo
foo*

View File

@ -19,3 +19,4 @@ select RTRIM(' foo ');
select trim(TRAILING 'x' FROM 'xxfooxx');
select Trim(LEADING 'ab' FROM 'abbafooabba');
select TRIM(both 'ab' FROM 'abbafooabbafooabba');
select trim(LEADING '*[]{}|\\' FROM '\\|[[[}}}*foo*');