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/*

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 *  matiec - a compiler for the programming languages defined in IEC 61131-3

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 *

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 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant

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 *

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 *  This program is free software: you can redistribute it and/or modify

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 *  it under the terms of the GNU General Public License as published by

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 *  the Free Software Foundation, either version 3 of the License, or

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 *  (at your option) any later version.

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 *

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 *  This program is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  GNU General Public License for more details.

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 *

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 *  You should have received a copy of the GNU General Public License

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 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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/*

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 * An IEC 61131-3 compiler.

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 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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/* Search in a VAR* END_VAR declaration for the delcration of the specified variable instance. 

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 * Will return:

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 *     - the declaration itself (get_decl() )

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 *     - the type of declaration in which the variable was declared (get_vartype() )

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 *

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 * The variable instance may NOT be a member of a structure of a memeber

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 * of a structure of an element of an array of ...

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 *

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 * For example, considering the following 'variables':

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 *    window.points[1].coordinate.x

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 *    window.points[1].colour

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 *    offset[99]

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 *

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 *   passing a reference to 'points', 'points[1]', 'points[1].colour', 'colour'

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 *    ARE NOT ALLOWED!

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 *

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 * This class must only be passed the name of the variable that will appear

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 * in the variable declaration. In the above examples, this would be

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 *   'window.points[1].coordinate.x'

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 *   'window.points[1].coordinate'

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 *   'window.points[1]'

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 *   'window'

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 *   'window.points[1].colour'

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 *   'offset'

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 *   'offset[99]'

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 *

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 *

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 */

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/* Note: 

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 * Determining the declaration type of a specific variable instance (including

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 * function block instances) really means determining whether the variable was declared in a

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 *  VAR_INPUT

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 *  VAR_OUTPUT

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 *  VAR_IN_OUT

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 *  VAR

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 *  VAR_TEMP

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 *  VAR_EXTERNAL

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 *  VAR_GLOBAL

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 *  VAR <var_name> AT <location>   -> Located variable!

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 * 

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 */

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/* Note:

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 *  The current_type_decl that this class returns may reference the

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 * name of a type, or the type declaration itself!

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 * For an example of the first, consider a variable declared as ...

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 * x : AAA;

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 * where the AAA type is previously declared as whatever.

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 * For an example of the second, consider a variable declared as ...

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 * x : array of int [10];  ---->  is allowed

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 *

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 * If it is the first, we will return a reference to the name, if the second

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 * we return a reference to the declaration!!

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 */

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#include "absyntax_utils.hh"

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/**********************************************/

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/*  A small helper visitor class, that will   */

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/*  return the name of a variable, as it will */

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/*  appear in the variable declaration.       */

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/**********************************************/

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/*  For ex.:

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 *       VAR

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 *          A : int;

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 *          B : ARRAY [1..9] of int;

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 *          C : some_struct_t;

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 *       END_VAR

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 *

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 *          A    := 56;

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 *          B[8] := 99;

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 *          C.e  := 77;

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 *

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 *       Calling this visitor class with symbolic_variable_c instance referencing 'A' in

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 *       the line 'A := 56', will return the string "A".

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 *

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 *       Calling this visitor class with array_variable_c instance referencing 'B[8]' in

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 *       the line 'B[8] := 99', will return the string "B".

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 *

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 *       Calling this visitor class with array_variable_c instance referencing 'C.e' in

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 *       the line 'C.e := 77', will return the string "C".

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 */

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class get_var_name_c : public search_visitor_c {

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  private:

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    static get_var_name_c *singleton_instance_;

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  public:

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    get_var_name_c(void)  {};

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    ~get_var_name_c(void) {};

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    static token_c *get_name(symbol_c *symbol) {

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      if (NULL == singleton_instance_) singleton_instance_ = new get_var_name_c(); 

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      if (NULL == singleton_instance_) ERROR; 

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      return (token_c *)(symbol->accept(*singleton_instance_));

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    }

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  private:  

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    /*************************/

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    /* B.1 - Common elements */

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    /*************************/

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    /*******************************************/

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    /* B 1.1 - Letters, digits and identifiers */

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    /*******************************************/

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    // SYM_TOKEN(identifier_c)

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    void *visit(identifier_c *symbol);

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    /*********************/

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    /* B 1.4 - Variables */

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    /*********************/

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    // SYM_REF2(symbolic_variable_c, var_name, unused)

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    void *visit(symbolic_variable_c *symbol);

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    /********************************************/

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    /* B.1.4.1   Directly Represented Variables */

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    /********************************************/

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    // SYM_TOKEN(direct_variable_c)

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    // void *visit(direct_variable_c *symbol);

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    /*************************************/

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    /* B.1.4.2   Multi-element Variables */

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    /*************************************/

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    /*  subscripted_variable '[' subscript_list ']' */

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    // SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

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    void *visit(array_variable_c *symbol);

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    /* subscript_list ',' subscript */

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    // SYM_LIST(subscript_list_c)

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    // void *visit(subscript_list_c *symbol);

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    /*  record_variable '.' field_selector */

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    /*  WARNING: input and/or output variables of function blocks

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     *           may be accessed as fields of a tructured variable!

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     *           Code handling a structured_variable_c must take

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     *           this into account!

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     */

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    // SYM_REF2(structured_variable_c, record_variable, field_selector)

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    void *visit(structured_variable_c *symbol);

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};

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get_var_name_c *get_var_name_c::singleton_instance_ = NULL;

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/*************************/

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/* B.1 - Common elements */

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/*************************/

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/*******************************************/

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/* B 1.1 - Letters, digits and identifiers */

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/*******************************************/

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// SYM_TOKEN(identifier_c)

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void *get_var_name_c::visit(identifier_c *symbol) {return (void *)symbol;}

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/*********************/

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/* B 1.4 - Variables */

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/*********************/

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// SYM_REF2(symbolic_variable_c, var_name, unused)

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void *get_var_name_c::visit(symbolic_variable_c *symbol) {return symbol->var_name->accept(*this);}

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/********************************************/

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/* B.1.4.1   Directly Represented Variables */

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/********************************************/

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// SYM_TOKEN(direct_variable_c)

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/*************************************/

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/* B.1.4.2   Multi-element Variables */

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/*************************************/

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/*  subscripted_variable '[' subscript_list ']' */

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// SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

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void *get_var_name_c::visit(array_variable_c *symbol) {return symbol->subscripted_variable->accept(*this);}

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/* subscript_list ',' subscript */

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// SYM_LIST(subscript_list_c)

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/*  record_variable '.' field_selector */

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/*  WARNING: input and/or output variables of function blocks

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 *           may be accessed as fields of a tructured variable!

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 *           Code handling a structured_variable_c must take

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 *           this into account!

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 */

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// SYM_REF2(structured_variable_c, record_variable, field_selector)

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void *get_var_name_c::visit(structured_variable_c *symbol) {return symbol->record_variable->accept(*this);}

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search_var_instance_decl_c::search_var_instance_decl_c(symbol_c *search_scope) {

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  this->current_vartype = none_vt;

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  this->search_scope = search_scope;

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  this->search_name = NULL;

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  this->current_type_decl = NULL;

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  this->current_option = none_opt;

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}

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symbol_c *search_var_instance_decl_c::get_decl(symbol_c *variable) {

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  this->current_vartype = none_vt;

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  this->current_option  = none_opt;

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  this->search_name = get_var_name_c::get_name(variable);

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  return (symbol_c *)search_scope->accept(*this);

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}

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unsigned int search_var_instance_decl_c::get_vartype(symbol_c *variable) {

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  this->current_vartype = none_vt;

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  this->current_option  = none_opt;

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  this->search_name = get_var_name_c::get_name(variable);

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  search_scope->accept(*this);

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  return this->current_vartype;

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}

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unsigned int search_var_instance_decl_c::get_option(symbol_c *variable) {

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  this->current_vartype = none_vt;

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  this->current_option  = none_opt;

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  this->search_name = get_var_name_c::get_name(variable);

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  search_scope->accept(*this);

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  return this->current_option;

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}

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/***************************/

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/* B 0 - Programming Model */

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/***************************/

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void *search_var_instance_decl_c::visit(library_c *symbol) {

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  /* we do not want to search multiple declaration scopes,

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   * so we do not visit all the functions, function blocks, etc...

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   */

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  return NULL;

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}

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/******************************************/

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/* B 1.4.3 - Declaration & Initialization */

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/******************************************/

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/* edge -> The F_EDGE or R_EDGE directive */

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// SYM_REF2(edge_declaration_c, edge, var1_list)

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// TODO

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void *search_var_instance_decl_c::visit(constant_option_c *symbol) {

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  current_option = constant_opt;

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  return NULL;

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}

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void *search_var_instance_decl_c::visit(retain_option_c *symbol) {

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  current_option = retain_opt;

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  return NULL;

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}

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void *search_var_instance_decl_c::visit(non_retain_option_c *symbol) {

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  current_option = non_retain_opt;

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  return NULL;

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}

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void *search_var_instance_decl_c::visit(input_declarations_c *symbol) {

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  current_vartype = input_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

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  if (NULL != symbol->option)  

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    symbol->option->accept(*this);

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  void *res = symbol->input_declaration_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option  = none_opt;

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  }

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  return res;

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}

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/* VAR_OUTPUT [RETAIN | NON_RETAIN] var_init_decl_list END_VAR */

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/* option -> may be NULL ! */

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void *search_var_instance_decl_c::visit(output_declarations_c *symbol) {

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  current_vartype = output_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

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  if (NULL != symbol->option)

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    symbol->option->accept(*this);

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  void *res = symbol->var_init_decl_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option  = none_opt;

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  }

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  return res;

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}

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/*  VAR_IN_OUT var_declaration_list END_VAR */

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void *search_var_instance_decl_c::visit(input_output_declarations_c *symbol) {

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  current_vartype = inoutput_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

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  void *res = symbol->var_declaration_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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  }

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  return res;

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}

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/* ENO : BOOL */

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void *search_var_instance_decl_c::visit(eno_param_declaration_c *symbol) {

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  if (compare_identifiers(symbol->name, search_name) == 0)

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    return symbol->type;

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  return NULL;

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}

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/* VAR [CONSTANT] var_init_decl_list END_VAR */

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/* option -> may be NULL ! */

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/* helper symbol for input_declarations */

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void *search_var_instance_decl_c::visit(var_declarations_c *symbol) {

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  current_vartype = private_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

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  if (NULL != symbol->option)

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    symbol->option->accept(*this);

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  void *res = symbol->var_init_decl_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option = none_opt;

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  }

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  return res;

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}

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/*  VAR RETAIN var_init_decl_list END_VAR */

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void *search_var_instance_decl_c::visit(retentive_var_declarations_c *symbol) {

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  current_vartype = private_vt;

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  current_option  = retain_opt;

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  void *res = symbol->var_init_decl_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option = none_opt;

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  }

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  return res;

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}

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/*  VAR [CONSTANT|RETAIN|NON_RETAIN] located_var_decl_list END_VAR */

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/* option -> may be NULL ! */

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//SYM_REF2(located_var_declarations_c, option, located_var_decl_list)

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void *search_var_instance_decl_c::visit(located_var_declarations_c *symbol) {

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  current_vartype = located_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

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  if (NULL != symbol->option)

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    symbol->option->accept(*this);

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  void *res = symbol->located_var_decl_list->accept(*this);

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  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option  = none_opt;

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  }

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  return res;

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}

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/*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */

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/* option -> may be NULL ! */

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//SYM_REF2(external_var_declarations_c, option, external_declaration_list)

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void *search_var_instance_decl_c::visit(external_var_declarations_c *symbol) {

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  current_vartype = external_vt;

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  current_option  = none_opt; /* not really required. Just to make the code more readable */

   392

  if (NULL != symbol->option)

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    symbol->option->accept(*this);

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  void *res = symbol->external_declaration_list->accept(*this);

   395

  if (res == NULL) {

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    current_vartype = none_vt;

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    current_option = none_opt;

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  }

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  return res;

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}

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   402

/*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */

   403

/* option -> may be NULL ! */

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//SYM_REF2(global_var_declarations_c, option, global_var_decl_list)

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void *search_var_instance_decl_c::visit(global_var_declarations_c *symbol) {

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  current_vartype = global_vt;

   407

  current_option  = none_opt; /* not really required. Just to make the code more readable */

   408

  if (NULL != symbol->option)

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    symbol->option->accept(*this);

   410

  void *res = symbol->global_var_decl_list->accept(*this);

   411

  if (res == NULL) {

   412

    current_vartype = none_vt;

   413

    current_option = none_opt;

   414

  }

   415

  return res;

   416

}

   417

   418

/* var1_list is one of the following...

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 *    simple_spec_init_c *

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 *    subrange_spec_init_c *

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 *    enumerated_spec_init_c *

   422

 */

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// SYM_REF2(var1_init_decl_c, var1_list, spec_init)

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void *search_var_instance_decl_c::visit(var1_init_decl_c *symbol) {

   425

  current_type_decl = symbol->spec_init;

   426

  return symbol->var1_list->accept(*this);

   427

}

   428

   429

/* var1_list ',' variable_name */

   430

// SYM_LIST(var1_list_c)

   431

void *search_var_instance_decl_c::visit(var1_list_c *symbol) {

   432

  list_c *list = symbol;

   433

  for(int i = 0; i < list->n; i++) {

   434

    if (compare_identifiers(list->elements[i], search_name) == 0)

   435

   /* by now, current_type_decl should be != NULL */

   436

      return current_type_decl;

   437

  }

   438

  return NULL;

   439

}

   440

   441

/* name_list ':' function_block_type_name ASSIGN structure_initialization */

   442

/* structure_initialization -> may be NULL ! */

   443

void *search_var_instance_decl_c::visit(fb_name_decl_c *symbol) {

   444

  current_type_decl = symbol->function_block_type_name;

   445

  return symbol->fb_name_list->accept(*this);

   446

}

   447

   448

/* name_list ',' fb_name */

   449

void *search_var_instance_decl_c::visit(fb_name_list_c *symbol) {

   450

  list_c *list = symbol;

   451

  for(int i = 0; i < list->n; i++) {

   452

    if (compare_identifiers(list->elements[i], search_name) == 0)

   453

    /* by now, current_fb_declaration should be != NULL */

   454

      return current_type_decl;

   455

  }

   456

  return NULL;

   457

}

   458

   459

/* var1_list ':' array_spec_init */

   460

// SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)

   461

void *search_var_instance_decl_c::visit(array_var_init_decl_c *symbol) {

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  current_type_decl = symbol->array_spec_init;

   463

  return symbol->var1_list->accept(*this);

   464

}

   465

   466

/*  var1_list ':' initialized_structure */

   467

// SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)

   468

void *search_var_instance_decl_c::visit(structured_var_init_decl_c *symbol) {

   469

  current_type_decl = symbol->initialized_structure;

   470

  return symbol->var1_list->accept(*this);

   471

}

   472

   473

/*  var1_list ':' array_specification */

   474

// SYM_REF2(array_var_declaration_c, var1_list, array_specification)

   475

void *search_var_instance_decl_c::visit(array_var_declaration_c *symbol) {

   476

  current_type_decl = symbol->array_specification;

   477

  return symbol->var1_list->accept(*this);

   478

}

   479

   480

/*  var1_list ':' structure_type_name */

   481

// SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)

   482

void *search_var_instance_decl_c::visit(structured_var_declaration_c *symbol) {

   483

  current_type_decl = symbol->structure_type_name;

   484

  return symbol->var1_list->accept(*this);

   485

}

   486

   487

/*  [variable_name] location ':' located_var_spec_init */

   488

/* variable_name -> may be NULL ! */

   489

// SYM_REF4(located_var_decl_c, variable_name, location, located_var_spec_init, unused)

   490

// TODO!!

   491

   492

/*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */

   493

// SYM_REF2(external_declaration_c, global_var_name, specification)

   494

void *search_var_instance_decl_c::visit(external_declaration_c *symbol) {

   495

  if (compare_identifiers(symbol->global_var_name, search_name) == 0)

   496

      return symbol->specification;

   497

  return NULL;

   498

}

   499

   500

/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */

   501

/* type_specification ->may be NULL ! */

   502

// SYM_REF2(global_var_decl_c, global_var_spec, type_specification)

   503

void *search_var_instance_decl_c::visit(global_var_decl_c *symbol) {

   504

  if (symbol->type_specification != NULL) {

   505

    current_type_decl = symbol->type_specification;

   506

    return symbol->global_var_spec->accept(*this);

   507