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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) 2009-2011  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 20011-2012 Manuele Conti (manuele.conti@sirius-es.it)

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 *  Copyright (C) 20011-2012 Matteo Facchinetti (matteo.facchinetti@sirius-es.it)

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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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 */

    25

    26

/*

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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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/*

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 *  Fill candidate list of data types for all symbols

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 */

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#include "print_datatypes_error.hh"

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#include <typeinfo>

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#include <list>

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#include <string>

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#include <string.h>

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#include <strings.h>

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/* A small helper class, to transform elementary data type to string.

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 * this allows us to generate more relevant error messages...

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 */

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class elementary_type_c: public null_visitor_c {

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  elementary_type_c(void) {};

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  ~elementary_type_c(void) {};

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  private:

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    /* singleton class! */

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    static elementary_type_c *singleton;

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  public:

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    static const char * to_string(symbol_c *symbol) {

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      if (NULL == singleton)    singleton = new elementary_type_c;

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      if (NULL == singleton)    ERROR;

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      const char *res           = (const char *)symbol->accept(*singleton);

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      if (NULL == res)          ERROR;

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      return res;

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    }

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    69

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

    70

    /* B 1.3.1 - Elementary Data Types */

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

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    void *visit(time_type_name_c *symbol)        {return (void *)"TIME";        };

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    void *visit(bool_type_name_c *symbol)        {return (void *)"BOOL";        };

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    void *visit(sint_type_name_c *symbol)        {return (void *)"SINT";        };

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    void *visit(int_type_name_c *symbol)         {return (void *)"INT";         };

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    void *visit(dint_type_name_c *symbol)        {return (void *)"DINT";        };

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    void *visit(lint_type_name_c *symbol)        {return (void *)"LINT";        };

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    void *visit(usint_type_name_c *symbol)       {return (void *)"USINT";       };

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    void *visit(uint_type_name_c *symbol)        {return (void *)"UINT";        };

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    void *visit(udint_type_name_c *symbol)       {return (void *)"UDINT";       };

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    void *visit(ulint_type_name_c *symbol)       {return (void *)"ULINT";       };

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    void *visit(real_type_name_c *symbol)        {return (void *)"REAL";        };

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    void *visit(lreal_type_name_c *symbol)       {return (void *)"LREAL";       };

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    void *visit(date_type_name_c *symbol)        {return (void *)"DATE";        };

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    void *visit(tod_type_name_c *symbol)         {return (void *)"TOD";         };

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    void *visit(dt_type_name_c *symbol)          {return (void *)"DT";          };

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    void *visit(byte_type_name_c *symbol)        {return (void *)"BYTE";        };

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    void *visit(word_type_name_c *symbol)        {return (void *)"WORD";        };

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    void *visit(lword_type_name_c *symbol)       {return (void *)"LWORD";       };

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    void *visit(dword_type_name_c *symbol)       {return (void *)"DWORD";       };

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    void *visit(string_type_name_c *symbol)      {return (void *)"STRING";      };

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    void *visit(wstring_type_name_c *symbol)     {return (void *)"WSTRING";     };

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    void *visit(safetime_type_name_c *symbol)    {return (void *)"SAFETIME";    };

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    void *visit(safebool_type_name_c *symbol)    {return (void *)"SAFEBOOL";    };

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    void *visit(safesint_type_name_c *symbol)    {return (void *)"SAFESINT";    };

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    void *visit(safeint_type_name_c *symbol)     {return (void *)"SAFEINT";     };

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    void *visit(safedint_type_name_c *symbol)    {return (void *)"SAFEDINT";    };

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    void *visit(safelint_type_name_c *symbol)    {return (void *)"SAFELINT";    };

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    void *visit(safeusint_type_name_c *symbol)   {return (void *)"SAFEUSINT";   };

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    void *visit(safeuint_type_name_c *symbol)    {return (void *)"SAFEUINT";    };

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    void *visit(safeudint_type_name_c *symbol)   {return (void *)"SAFEUDINT";   };

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    void *visit(safeulint_type_name_c *symbol)   {return (void *)"SAFEULINT";   };

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    void *visit(safereal_type_name_c *symbol)    {return (void *)"SAFEREAL";    };

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    void *visit(safelreal_type_name_c *symbol)   {return (void *)"SAFELREAL";   };

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    void *visit(safedate_type_name_c *symbol)    {return (void *)"SAFEDATE";    };

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    void *visit(safetod_type_name_c *symbol)     {return (void *)"SAFETOD";     };

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    void *visit(safedt_type_name_c *symbol)      {return (void *)"SAFEDT";      };

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    void *visit(safebyte_type_name_c *symbol)    {return (void *)"SAFEBYTE";    };

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    void *visit(safeword_type_name_c *symbol)    {return (void *)"SAFEWORD";    };

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    void *visit(safelword_type_name_c *symbol)   {return (void *)"SAFELWORD";   };

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    void *visit(safedword_type_name_c *symbol)   {return (void *)"SAFEDWORD";   };

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    void *visit(safestring_type_name_c *symbol)  {return (void *)"SAFESTRING";  };

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    void *visit(safewstring_type_name_c *symbol) {return (void *)"SAFEWSTRING"; };

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};

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elementary_type_c *elementary_type_c::singleton = NULL;

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#define FIRST_(symbol1, symbol2) (((symbol1)->first_order < (symbol2)->first_order)   ? (symbol1) : (symbol2))

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#define  LAST_(symbol1, symbol2) (((symbol1)->last_order  > (symbol2)->last_order)    ? (symbol1) : (symbol2))

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#define STAGE3_ERROR(error_level, symbol1, symbol2, ...) {                                                                  \

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  if (current_display_error_level >= error_level) {                                                                         \

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    fprintf(stderr, "%s:%d-%d..%d-%d: error : ",                                                                            \

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            FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\

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                                                 LAST_(symbol1,symbol2) ->last_line,  LAST_(symbol1,symbol2) ->last_column);\

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    fprintf(stderr, __VA_ARGS__);                                                                                           \

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    fprintf(stderr, "\n");                                                                                                  \

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    il_error = true;                                                                                                        \

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    error_found = true;                                                                                                     \

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  }                                                                                                                         \

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}  

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   139

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/* set to 1 to see debug info during execution */

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static int debug = 0;

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print_datatypes_error_c::print_datatypes_error_c(symbol_c *ignore) {

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	error_found = false;

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	current_display_error_level = error_level_default;

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}

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   148

print_datatypes_error_c::~print_datatypes_error_c(void) {

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}

   150

   151

int print_datatypes_error_c::get_error_found() {

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	return error_found;

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}

   154

   155

/* a helper function... */

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symbol_c *print_datatypes_error_c::base_type(symbol_c *symbol) {

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	/* NOTE: symbol == NULL is valid. It will occur when, for e.g., an undefined/undeclared symbolic_variable is used

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	 *       in the code.

   159

	 */

   160

	if (symbol == NULL) return NULL;

   161

	return (symbol_c *)symbol->accept(search_base_type);

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}

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

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/* B 1.2 - Constants */

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

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

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/* B 1.2.1 - Numeric Literals */

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

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void *print_datatypes_error_c::visit(real_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_REAL data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

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	}

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	return NULL;

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}

   178

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void *print_datatypes_error_c::visit(integer_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   182

	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

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	}

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	return NULL;

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}

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void *print_datatypes_error_c::visit(neg_real_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_REAL data type.");

   191

	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

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	}

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	return NULL;

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}

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   197

void *print_datatypes_error_c::visit(neg_integer_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   200

	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   202

	}

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	return NULL;

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}

   205

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void *print_datatypes_error_c::visit(binary_integer_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

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	}

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	return NULL;

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}

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void *print_datatypes_error_c::visit(octal_integer_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

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	}

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	return NULL;

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}

   223

   224

void *print_datatypes_error_c::visit(hex_integer_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   227

	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

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	}

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	return NULL;

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}

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   233

void *print_datatypes_error_c::visit(integer_literal_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

   236

	} else if (NULL == symbol->datatype) {

   237

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   238

	}

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	return NULL;

   240

}

   241

   242

void *print_datatypes_error_c::visit(real_literal_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

   247

	}

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	return NULL;

   249

}

   250

   251

void *print_datatypes_error_c::visit(bit_string_literal_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

   254

	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_BIT data type not valid in this location.");

   256

	}

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	return NULL;

   258

}

   259

   260

void *print_datatypes_error_c::visit(boolean_literal_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for %s data type.", elementary_type_c::to_string(symbol->type));

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

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	}

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	return NULL;

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}

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void *print_datatypes_error_c::visit(boolean_true_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for ANY_BOOL data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

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	}

   275

	return NULL;

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}

   277

   278

void *print_datatypes_error_c::visit(boolean_false_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for ANY_BOOL data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

   283

	}

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	return NULL;

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}

   286

   287

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

   288

/* B.1.2.2   Character Strings */

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

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void *print_datatypes_error_c::visit(double_byte_character_string_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for WSTRING data type.");

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	} else if (NULL == symbol->datatype) {

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		STAGE3_ERROR(4, symbol, symbol, "WSTRING data type not valid in this location.");

   295

	}

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	return NULL;

   297

}

   298

   299

void *print_datatypes_error_c::visit(single_byte_character_string_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for STRING data type.");

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	} else if (NULL == symbol->datatype) {

   303

		STAGE3_ERROR(4, symbol, symbol, "STRING data type not valid in this location.");

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	}

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	return NULL;

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}

   307

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

   309

/* B 1.2.3 - Time Literals */

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

   311

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

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/* B 1.2.3.1 - Duration */

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

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void *print_datatypes_error_c::visit(duration_c *symbol) {

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	if (symbol->candidate_datatypes.size() == 0) {

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		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for TIME data type.");

   317

	} else if (NULL == symbol->datatype) {

   318

		STAGE3_ERROR(4, symbol, symbol, "TIME data type not valid in this location.");

   319

	}

   320

	return NULL;

   321

}

   322

   323

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

   324

/* B 1.2.3.2 - Time of day and Date */

   325

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

   326

void *print_datatypes_error_c::visit(time_of_day_c *symbol) {

   327

	if (symbol->candidate_datatypes.size() == 0) {

   328

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for TOD data type.");

   329

	} else if (NULL == symbol->datatype) {

   330

		STAGE3_ERROR(4, symbol, symbol, "TOD data type not valid in this location.");

   331

	}

   332

	return NULL;

   333

}

   334

   335

void *print_datatypes_error_c::visit(date_c *symbol) {

   336

	if (symbol->candidate_datatypes.size() == 0) {

   337

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for DATE data type.");

   338

	} else if (NULL == symbol->datatype) {

   339

		STAGE3_ERROR(4, symbol, symbol, "DATE data type not valid in this location.");

   340

	}

   341

	return NULL;

   342

}

   343

   344

void *print_datatypes_error_c::visit(date_and_time_c *symbol) {

   345

	if (symbol->candidate_datatypes.size() == 0) {

   346

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for DT data type.");

   347

	} else if (NULL == symbol->datatype) {

   348

		STAGE3_ERROR(4, symbol, symbol, "DT data type not valid in this location.");

   349

	}

   350

	return NULL;

   351

}

   352

   353

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

   354

/* B 1.3 - Data types */

   355

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

   356

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

   357

/* B 1.3.3 - Derived data types */

   358

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

   359

void *print_datatypes_error_c::visit(data_type_declaration_c *symbol) {

   360

	// TODO !!!

   361

	/* for the moment we must return NULL so semantic analysis of remaining code is not interrupted! */

   362

	return NULL;

   363

}

   364

   365

void *print_datatypes_error_c::visit(enumerated_value_c *symbol) {

   366

	if (symbol->candidate_datatypes.size() == 0)

   367

		STAGE3_ERROR(0, symbol, symbol, "Ambiguous enumerate value or Variable not declared in this scope.");

   368

	return NULL;

   369

}

   370

   371

   372

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

   373

/* B 1.4 - Variables */

   374

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

   375

void *print_datatypes_error_c::visit(symbolic_variable_c *symbol) {

   376

	if (symbol->candidate_datatypes.size() == 0)

   377

		STAGE3_ERROR(0, symbol, symbol, "Variable not declared in this scope.");

   378

	return NULL;

   379

}

   380

   381

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

   382

/* B 1.4.1 - Directly Represented Variables */

   383

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

   384

void *print_datatypes_error_c::visit(direct_variable_c *symbol) {

   385

	if (symbol->candidate_datatypes.size() == 0)

   386

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for located variable data type.");

   387

	return NULL;

   388

}

   389

   390

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

   391

/* B 1.4.2 - Multi-element variables */

   392

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

   393

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

   394

// SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   395

void *print_datatypes_error_c::visit(array_variable_c *symbol) {

   396

	if (symbol->candidate_datatypes.size() == 0)

   397

		STAGE3_ERROR(0, symbol, symbol, "Array variable not declared in this scope.");

   398

   399

	/* recursively call the subscript list to print any errors in the expressions used in the subscript...*/

   400

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

   401

	return NULL;

   402

}

   403

   404

/* subscript_list ',' subscript */

   405

// SYM_LIST(subscript_list_c)

   406

/* NOTE: we inherit from iterator visitor, so we do not need to implement this method... */

   407

#if 0

   408

void *print_datatypes_error_c::visit(subscript_list_c *symbol) {

   409

}

   410

#endif

   411

   412

   413

/*  record_variable '.' field_selector */

   414

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

   415

 *           may be accessed as fields of a structured variable!

   416

 *           Code handling a structured_variable_c must take

   417

 *           this into account!

   418

 */

   419

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   420

/* NOTE: We do not recursively determine the data types of each field_selector in fill_candidate_datatypes_c,

   421

 * so it does not make sense to recursively visit all the field_selectors to print out error messages. 

   422

 * Maybe in the future, if we find the need to print out more detailed error messages, we might do it that way. For now, we don't!

   423

 */

   424

void *print_datatypes_error_c::visit(structured_variable_c *symbol) {

   425

	if (symbol->candidate_datatypes.size() == 0)

   426

		STAGE3_ERROR(0, symbol, symbol, "Structure variable not declared in this scope.");

   427

	return NULL;

   428

}

   429

   430

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

   431

/* B 1.5 Program organization units */

   432

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

   433

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

   434

/* B 1.5.1 Functions */

   435

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

   436

void *print_datatypes_error_c::visit(function_declaration_c *symbol) {

   437

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   438

	/* We do not check for data type errors in variable declarations, Skip this for now... */

   439

// 	symbol->var_declarations_list->accept(*this);

   440

	if (debug) printf("Print error data types list in body of function %s\n", ((token_c *)(symbol->derived_function_name))->value);

   441

	il_parenthesis_level = 0;

   442

	il_error = false;

   443

	prev_il_instruction = NULL;

   444

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

   445

	prev_il_instruction = NULL;

   446

	delete search_varfb_instance_type;

   447

	search_varfb_instance_type = NULL;

   448

	return NULL;

   449

}

   450

   451

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

   452

/* B 1.5.2 Function blocks */

   453

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

   454

void *print_datatypes_error_c::visit(function_block_declaration_c *symbol) {

   455

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   456

	/* We do not check for data type errors in variable declarations, Skip this for now... */

   457

// 	symbol->var_declarations->accept(*this);

   458

	if (debug) printf("Print error data types list in body of FB %s\n", ((token_c *)(symbol->fblock_name))->value);

   459

	il_parenthesis_level = 0;

   460

	il_error = false;

   461

	prev_il_instruction = NULL;

   462

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

   463

	prev_il_instruction = NULL;

   464

	delete search_varfb_instance_type;

   465

	search_varfb_instance_type = NULL;

   466

	return NULL;

   467

}

   468

   469

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

   470

/* B 1.5.3 - Programs */

   471

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

   472

void *print_datatypes_error_c::visit(program_declaration_c *symbol) {

   473

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   474

	/* We do not check for data type errors in variable declarations, Skip this for now... */

   475

// 	symbol->var_declarations->accept(*this);

   476

	if (debug) printf("Print error data types list in body of program %s\n", ((token_c *)(symbol->program_type_name))->value);

   477

	il_parenthesis_level = 0;

   478

	il_error = false;

   479

	prev_il_instruction = NULL;

   480

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

   481

	prev_il_instruction = NULL;

   482

	delete search_varfb_instance_type;

   483

	search_varfb_instance_type = NULL;

   484

	return NULL;

   485

}

   486

   487

   488

   489

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

   490

/* B 1.7 Configuration elements */

   491

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

   492

void *print_datatypes_error_c::visit(configuration_declaration_c *symbol) {

   493

#if 0

   494

	// TODO !!!

   495

	/* for the moment we must return NULL so semantic analysis of remaining code is not interrupted! */

   496

#endif

   497

	return NULL;

   498

}

   499

   500

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

   501

/* B.2 - Language IL (Instruction List) */

   502

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

   503

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

   504

/* B 2.1 Instructions and Operands */

   505

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

   506

// void *visit(instruction_list_c *symbol);

   507

void *print_datatypes_error_c::visit(il_simple_operation_c *symbol) {

   508

	il_operand = symbol->il_operand;

   509

	if (NULL != symbol->il_operand) {

   510

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

   511

	}

   512

	/* recursive call to see whether data types are compatible */

   513

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

   514

	il_operand = NULL;

   515

	return NULL;

   516

}