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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// specific language governing permissions and limitations
// under the License.

#ifndef IMPALA_UTIL_SYMBOLS_UTIL_H
#define IMPALA_UTIL_SYMBOLS_UTIL_H

#include <string>
#include "runtime/types.h"

namespace impala {

/// Utility class to manipulate c++/IR symbols, mangling and demangling names.
class SymbolsUtil {
 public:
  /// Returns true if this symbol is mangled.
  static bool IsMangled(const std::string& symbol);

  /// Returns the demangled string. The name is assumed to be a mangled string using the
  /// gcc/llvm convention.
  /// Returns the original input if it cannot be demangled.
  static std::string Demangle(const std::string& name);

  /// Returns the fully-qualified function name of 'symbol' (i.e. it strips the arguments
  /// but retains any namespace and class names). 'symbol' may be mangled or unmangled.
  /// Returns the original input if it cannot be demangled.
  /// Example: "impala::foo(int arg1)" => "impala::foo"
  static std::string DemangleNoArgs(const std::string& symbol);

  /// Returns the function name of 'symbol' (i.e., it strips the arguments and any
  /// namespace/class qualifiers). 'symbol' may be mangled or unmangled.
  /// Returns the original input if it cannot be demangled.
  /// Example: "impala::foo(int arg1)" => "foo"
  static std::string DemangleNameOnly(const std::string& symbol);

  /// Mangles fn_name with 'arg_types' to the function signature for user functions.
  /// This maps types to AnyVal* and automatically adds the FunctionContext*
  /// as the first argument.
  /// The fn_name must be fully qualified. i.e namespace::class::fn.
  /// if 'has_var_args' is true, the last argument in arg_types can be variable.
  /// if 'ret_argument' is non-null, it is added as a last return argument.
  /// TODO: this is not a general mangling function and that is more difficult to
  /// do. Find a library to do this.
  /// There is no place we require this to be perfect, if we can't do this right,
  /// the user will need to specify the full mangled string.
  static std::string MangleUserFunction(const std::string& fn_name,
      const std::vector<ColumnType>& arg_types, bool has_var_args = false,
      ColumnType* ret_argument = NULL);

  /// Mangles fn_name assuming arguments
  /// (impala_udf::FunctionContext*, impala_udf::FunctionContext::FunctionStateScope).
  static std::string ManglePrepareOrCloseFunction(const std::string& fn_name);
};

}

#endif