Chris@16: /*=============================================================================
Chris@16:     Boost.Wave: A Standard compliant C++ preprocessor library
Chris@16: 
Chris@16:     http://www.boost.org/
Chris@16: 
Chris@16:     State machine detecting include guards in an included file. 
Chris@16:     This detects two forms of include guards:
Chris@16: 
Chris@16:         #ifndef INCLUDE_GUARD_MACRO
Chris@16:         #define INCLUDE_GUARD_MACRO
Chris@16:         ...
Chris@16:         #endif
Chris@16: 
Chris@16:     or
Chris@16: 
Chris@16:         if !defined(INCLUDE_GUARD_MACRO)
Chris@16:         #define INCLUDE_GUARD_MACRO
Chris@16:         ...
Chris@16:         #endif
Chris@16: 
Chris@16:     note, that the parenthesis are optional (i.e. !defined INCLUDE_GUARD_MACRO
Chris@16:     will work as well). The code allows for any whitespace, newline and single 
Chris@16:     '#' tokens before the #if/#ifndef and after the final #endif.
Chris@16: 
Chris@16:     Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under the Boost
Chris@16:     Software License, Version 1.0. (See accompanying file
Chris@16:     LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: =============================================================================*/
Chris@16: #if !defined(DETECT_INCLUDE_GUARDS_HK060304_INCLUDED)
Chris@16: #define DETECT_INCLUDE_GUARDS_HK060304_INCLUDED
Chris@16: 
Chris@16: #include <boost/wave/wave_config.hpp>
Chris@16: #include <boost/wave/token_ids.hpp>
Chris@16: 
Chris@16: // this must occur after all of the includes and before any code appears
Chris@16: #ifdef BOOST_HAS_ABI_HEADERS
Chris@16: #include BOOST_ABI_PREFIX
Chris@16: #endif
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: namespace boost {
Chris@16: namespace wave {
Chris@16: namespace cpplexer {
Chris@16: 
Chris@16: template <typename Token>
Chris@16: class include_guards
Chris@16: {
Chris@16: public:
Chris@16:     include_guards()
Chris@16:     :   state(&include_guards::state_0), detected_guards(false), 
Chris@16:         current_state(true), if_depth(0)
Chris@16:     {}
Chris@16: 
Chris@16:     Token& detect_guard(Token& t) 
Chris@16:         { return current_state ? (this->*state)(t) : t; }
Chris@16:     bool detected(std::string& guard_name_) const 
Chris@16:     {
Chris@16:         if (detected_guards) {
Chris@16:             guard_name_ = guard_name.c_str();
Chris@16:             return true;
Chris@16:         }
Chris@16:         return false; 
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     typedef Token& state_type(Token& t);
Chris@16:     state_type include_guards::* state;
Chris@16: 
Chris@16:     bool detected_guards;
Chris@16:     bool current_state;
Chris@16:     typename Token::string_type guard_name;
Chris@16:     int if_depth;
Chris@16: 
Chris@16:     state_type state_0, state_1, state_2, state_3, state_4, state_5;
Chris@16:     state_type state_1a, state_1b, state_1c, state_1d, state_1e;
Chris@16: 
Chris@16:     bool is_skippable(token_id id) const
Chris@16:     {
Chris@16:         return (T_POUND == BASE_TOKEN(id) || 
Chris@16:                 IS_CATEGORY(id, WhiteSpaceTokenType) ||
Chris@16:                 IS_CATEGORY(id, EOLTokenType));
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 0: beginning of a file, tries to recognize #ifndef or #if tokens
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_0(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_PP_IFNDEF == id)
Chris@16:         state = &include_guards::state_1;
Chris@16:     else if (T_PP_IF == id)
Chris@16:         state = &include_guards::state_1a;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1: found #ifndef, looking for T_IDENTIFIER
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_IDENTIFIER == id) {
Chris@16:         guard_name = t.get_value();
Chris@16:         state = &include_guards::state_2;
Chris@16:     }
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1a: found T_PP_IF, looking for T_NOT ("!")
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1a(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_NOT == BASE_TOKEN(id)) 
Chris@16:         state = &include_guards::state_1b;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1b: found T_NOT, looking for 'defined'
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1b(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_IDENTIFIER == id && t.get_value() == "defined") 
Chris@16:         state = &include_guards::state_1c;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1c: found 'defined', looking for (optional) T_LEFTPAREN
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1c(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_LEFTPAREN == id) 
Chris@16:         state = &include_guards::state_1d;
Chris@16:     else if (T_IDENTIFIER == id) {
Chris@16:         guard_name = t.get_value();
Chris@16:         state = &include_guards::state_2;
Chris@16:     }
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1d: found T_LEFTPAREN, looking for T_IDENTIFIER guard
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1d(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_IDENTIFIER == id) {
Chris@16:         guard_name = t.get_value();
Chris@16:         state = &include_guards::state_1e;
Chris@16:     }
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 1e: found T_IDENTIFIER guard, looking for T_RIGHTPAREN
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_1e(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_RIGHTPAREN == id) 
Chris@16:         state = &include_guards::state_2;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 2: found T_IDENTIFIER, looking for #define
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_2(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_PP_DEFINE == id) 
Chris@16:         state = &include_guards::state_3;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 3: found #define, looking for T_IDENTIFIER as recognized by state 1
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_3(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_IDENTIFIER == id && t.get_value() == guard_name)
Chris@16:         state = &include_guards::state_4;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 4: found guard T_IDENTIFIER, looking for #endif
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_4(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_PP_IF == id || T_PP_IFDEF == id || T_PP_IFNDEF == id)
Chris@16:         ++if_depth;
Chris@16:     else if (T_PP_ENDIF == id) {
Chris@16:         if (if_depth > 0)
Chris@16:             --if_depth;
Chris@16:         else
Chris@16:             state = &include_guards::state_5;
Chris@16:     }
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: //  state 5: found final #endif, looking for T_EOF
Chris@16: template <typename Token>
Chris@16: inline Token& 
Chris@16: include_guards<Token>::state_5(Token& t)
Chris@16: {
Chris@16:     token_id id = token_id(t);
Chris@16:     if (T_EOF == id) 
Chris@16:         detected_guards = current_state;
Chris@16:     else if (!is_skippable(id))
Chris@16:         current_state = false;
Chris@16:     return t;
Chris@16: }
Chris@16: 
Chris@16: ///////////////////////////////////////////////////////////////////////////////
Chris@16: }   // namespace cpplexer
Chris@16: }   // namespace wave
Chris@16: }   // namespace boost
Chris@16: 
Chris@16: // the suffix header occurs after all of the code
Chris@16: #ifdef BOOST_HAS_ABI_HEADERS
Chris@16: #include BOOST_ABI_SUFFIX
Chris@16: #endif
Chris@16: 
Chris@16: #endif // !DETECT_INCLUDE_GUARDS_HK060304_INCLUDED