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/*

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 * (c) 2003 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

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 * as published by the Free Software Foundation; either version 2 of the

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 * License, or (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, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

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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 IL and ST 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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    25

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/*

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 * Conversion of basic abstract syntax constructs.

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 *

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 * This is part of the 4th stage that generates

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 * a c++ source program equivalent to the IL and ST

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 * code.

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 */

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//#include <stdio.h>  /* required for NULL */

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//#include <string>

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//#include <iostream>

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//#include "../../util/symtable.hh"

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    45

//#include "generate_c.hh"

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#include <string.h>

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typedef struct

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{

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  symbol_c *param_value;

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  symbol_c *param_type;

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  function_param_iterator_c::param_direction_t param_direction;

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} FUNCTION_PARAM;

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#define ADD_PARAM_LIST(value, type, direction)\

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  param = new FUNCTION_PARAM;\

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  param->param_value = value;\

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  param->param_type = type;\

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  param->param_direction = direction;\

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  param_list.push_back(*param);

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class generate_c_base_c: public iterator_visitor_c {

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  protected:

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    stage4out_c &s4o;

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  private:

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    /* Unlike programs that are mapped onto C++ classes, Function Blocks are mapped onto a data structure type

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     * and a separate function conatining the code. This function is passed a pointer to an instance of the data

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     * structure. This means that the code inside the functions must insert a pointer to the data structure whenever

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     * it wishes to access a Function Block variable.

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     * The variable_prefix_ variable will contain the correct string which needs to be prefixed to all variable accesses.

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     * This string is set with the set_variable_prefix() member function.

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     */

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    const char *variable_prefix_;

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  public:

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    generate_c_base_c(stage4out_c *s4o_ptr): s4o(*s4o_ptr) {variable_prefix_ = NULL;}

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    ~generate_c_base_c(void) {}

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    void set_variable_prefix(const char *variable_prefix) {variable_prefix_ = variable_prefix;}

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    const char *get_variable_prefix(void) {return variable_prefix_;}

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    bool is_variable_prefix_null(void) {return variable_prefix_ == NULL;}

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    void print_variable_prefix(void) {

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      if (variable_prefix_ != NULL)

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        s4o.print(variable_prefix_);

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    }

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    void *print_token(token_c *token, int offset = 0) {

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      return s4o.printupper((token->value)+offset);

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    }

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    void *print_literal(symbol_c *type, symbol_c *value) {

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      s4o.print("__");

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      type->accept(*this);

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      s4o.print("_LITERAL(");

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      value->accept(*this);

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      s4o.print(")");

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      return NULL;

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    }

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    void *print_striped_token(token_c *token, int offset = 0) {

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      std::string str = "";

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      for (unsigned int i = offset; i < strlen(token->value); i++)

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        if (token->value[i] != '_')

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          str += token->value[i];

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      return s4o.printupper(str);

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    }

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    void *print_striped_binary_token(token_c *token, unsigned int offset = 0) {

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      /* convert the binary value to hexadecimal format... */

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      unsigned char value, bit_mult;

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      unsigned int i;

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      int total_bits;

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      char str[2] = {'A', '\0'};  /* since the s4o object is not prepared to print out one character at a time... */

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      s4o.print("0x");

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      total_bits = 0;

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      for (i = offset; i < strlen(token->value); i++)

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        if (token->value[i] != '_')

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	  total_bits++;

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      value = 0;

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      bit_mult = (unsigned char)1 << (((total_bits+3)%4)+1);

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      for (i = offset; i < strlen(token->value); i++) {

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        if (token->value[i] != '_') {

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	  bit_mult /= 2;

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	  value += bit_mult * ((token->value[i] == '0')? 0:1);

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	  if (bit_mult == 1) {

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	    str[0] = (value <= 9)? (char)'0' + value : (char)'A' + value;

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	    s4o.print(str);

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            bit_mult = 0x10;

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            value = 0;

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	  }

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	}

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      }

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      return NULL;

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    }

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    void *print_list(list_c *list,

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		     std::string pre_elem_str = "",

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		     std::string inter_elem_str = "",

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		     std::string post_elem_str = "",

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		     visitor_c *visitor = NULL) {

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      if (visitor == NULL) visitor = this;

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      if (list->n > 0) {

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//std::cout << "generate_c_base_c::print_list(n = " << list->n << ")   000\n";

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        s4o.print(pre_elem_str);

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        list->elements[0]->accept(*visitor);

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      }

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      for(int i = 1; i < list->n; i++) {

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//std::cout << "generate_c_base_c::print_list   " << i << "\n";

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        s4o.print(inter_elem_str);

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        list->elements[i]->accept(*visitor);

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      }

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      if (list->n > 0)

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        s4o.print(post_elem_str);

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      return NULL;

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    }

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    void *print_binary_expression(symbol_c *l_exp,

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				  symbol_c *r_exp,

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				  const char *operation) {

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      s4o.print("(");

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      l_exp->accept(*this);

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      s4o.print(operation);

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      r_exp->accept(*this);

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      s4o.print(")");

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      return NULL;

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    }

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    void *print_unary_expression(symbol_c *exp,

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				 const char *operation) {

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      s4o.print(operation);

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      s4o.print("(");

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      exp->accept(*this);

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      s4o.print(")");

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      return NULL;

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    }

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    void *print_binary_function(const char *function,

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          symbol_c *l_exp,

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				  symbol_c *r_exp) {

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      s4o.print(function);

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      s4o.print("(");

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      l_exp->accept(*this);

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      s4o.print(", ");

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      r_exp->accept(*this);

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      s4o.print(")");

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      return NULL;

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   	}

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    void *print_compare_function(const char *function,

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          symbol_c *compare_type,

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          symbol_c *l_exp,

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          symbol_c *r_exp) {

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      s4o.print(function);

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      compare_type->accept(*this);

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      s4o.print("(__BOOL_LITERAL(TRUE), NULL, 2, ");

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      l_exp->accept(*this);

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      s4o.print(", ");

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      r_exp->accept(*this);

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      s4o.print(")");

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      return NULL;

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    }

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

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/* 2.1.6 - Pragmas */

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

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    /* Do not use print_token() as it will change everything into uppercase */

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    void *visit(pragma_c *symbol) {return s4o.print(symbol->value);}

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

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/* B 0 - Programming Model */

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

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  /* leave for derived classes... */

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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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    void *visit(identifier_c *symbol) {return print_token(symbol);}

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

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/* B 1.2 - Constants */

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

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  /* originally empty... */

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

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/* B 1.2.1 - Numeric Literals */

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

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    void *visit(real_c *symbol) {return print_striped_token(symbol);}

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    void *visit(integer_c *symbol) {return print_striped_token(symbol);}

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    void *visit(binary_integer_c *symbol) {return print_striped_binary_token(symbol, 2);}

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    void *visit(octal_integer_c *symbol) {s4o.print("0"); return print_striped_token(symbol, 2);}

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    void *visit(hex_integer_c *symbol) {s4o.print("0x"); return print_striped_token(symbol, 3);}

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    void *visit(integer_literal_c *symbol) {return print_literal(symbol->type, symbol->value);}

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    void *visit(real_literal_c *symbol) {return print_literal(symbol->type, symbol->value);}

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    void *visit(bit_string_literal_c *symbol) {return print_literal(symbol->type, symbol->value);}

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    /* helper class for boolean_literal_c */

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    void *visit(boolean_true_c *symbol) {s4o.print("TRUE"); return NULL;}

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    void *visit(boolean_false_c *symbol) {s4o.print("FALSE"); return NULL;}

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    void *visit(neg_expression_c *symbol) {

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      s4o.print("-");

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

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      return NULL;

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    }

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

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/* B.1.2.2   Character Strings */

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

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    void *visit(double_byte_character_string_c *symbol) {

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      // TO DO ...

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      ERROR;

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      return print_token(symbol);

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    }

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   301

    void *visit(single_byte_character_string_c *symbol) {

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      std::string str = "";

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      unsigned int count = 0; 

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      str += '"';

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      /* we ignore the first and last bytes, they will be the character ' */

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      for (unsigned int i = 1; i < strlen(symbol->value) - 1; i++) {

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        char c = symbol->value[i];

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        if ((c == '\\') || (c == '"'))

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          {str += '\\'; str += c; count ++; continue;}

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        if (c != '$')

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          {str += c; count++; continue;}

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        /* this should be safe, since the code has passed the syntax parser!! */

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        c = symbol->value[++i];

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        switch (c) {

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          case '$':

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          case '\'':

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            {str += c; count++; continue;}

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          case 'L':

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          case 'l':

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            {str += "\x0A"; /* LF */; count++; continue;}

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          case 'N':

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          case 'n':

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            {str += "\\x0A"; /* NL */; count++; continue;}

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          case 'P':

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          case 'p':

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            {str += "\\f"; /* FF */; count++; continue;}

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          case 'R':

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          case 'r':

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            {str += "\\r"; /* CR */; count++; continue;}

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          case 'T':

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          case 't':

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            {str += "\\t"; /* tab */; count++; continue;}

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          default: {

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            if (isxdigit(c)) {

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              /* this should be safe, since the code has passed the syntax parser!! */

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	      char c2 = symbol->value[++i];

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	      if (isxdigit(c2)) {

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	        str += '\\'; str += 'x'; str += c; str += c2;

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	        count++; continue;

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	      }

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	    }

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          }

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          /* otherwise we have an invalid string!! */

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          /* This should not have got through the syntax parser! */

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          ERROR;

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        } /* switch() */

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      } /* for() */

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      str += '"';

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      s4o.print("(STRING){");

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      s4o.print_integer(count); 

   352

      s4o.print(",");

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      s4o.print(str);

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      s4o.print("}");

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      return NULL;

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    }

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

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/* B 1.2.3 - Time Literals */

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

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

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/* B 1.2.3.1 - Duration */

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

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/* The following output is actually the parameters to the constructor of the TIME class! */

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/* SYM_REF0(neg_time_c) */

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void *visit(neg_time_c *symbol) {s4o.print("-1"); /* negative time value */; return NULL;}

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/* SYM_REF2(duration_c, neg, interval) */

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void *visit(duration_c *symbol) {

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  TRACE("duration_c");

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  s4o.print("__time_to_timespec(");

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  if (NULL == symbol->neg)

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    s4o.print("1");  /* positive time value */

   378

  else

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    symbol->neg->accept(*this);  /* this will print '-1'   :-) */

   380

   381

  s4o.print(", ");

   382

   383

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

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  if (typeid(*symbol->interval) == typeid(hours_c)) {s4o.print(", 0");}

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  if (typeid(*symbol->interval) == typeid(minutes_c)) {s4o.print(", 0, 0");}

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  if (typeid(*symbol->interval) == typeid(seconds_c)) {s4o.print(", 0, 0, 0");}

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  if (typeid(*symbol->interval) == typeid(milliseconds_c)) {s4o.print(", 0, 0, 0, 0");}

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  s4o.print(")");

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  return NULL;

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}

   391

   392

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/* SYM_TOKEN(fixed_point_c) */

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void *visit(fixed_point_c *symbol) {return print_token(symbol);}

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/* SYM_REF2(days_c, days, hours) */

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void *visit(days_c *symbol) {

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  TRACE("days_c");

   400

  if (NULL == symbol->hours)

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    s4o.print("0, 0, 0, 0");  /* milliseconds, seconds, minutes, hours */

   402

  else

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

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   405

  s4o.print(", ");

   406

   407

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

   408

  return NULL;

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}

   410

   411

   412

/* SYM_REF2(hours_c, hours, minutes) */

   413

void *visit(hours_c *symbol) {

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  TRACE("hours_c");

   415

  if (NULL == symbol->minutes)

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    s4o.print("0, 0, 0");  /* milliseconds, seconds, minutes */

   417

  else

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

   419

   420

  s4o.print(", ");

   421

   422

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

   423

  return NULL;

   424

}

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/* SYM_REF2(minutes_c, minutes, seconds) */

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void *visit(minutes_c *symbol) {

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  TRACE("minutes_c");

   430

  if (NULL == symbol->seconds)

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    s4o.print("0, 0");  /* milliseconds, seconds */

   432

  else

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

   434

   435

  s4o.print(", ");

   436

   437

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

   438

  return NULL;

   439

}

   440

   441

   442

/* SYM_REF2(seconds_c, seconds, milliseconds) */

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void *visit(seconds_c *symbol) {

   444

  TRACE("seconds_c");

   445

  if (NULL == symbol->milliseconds)

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    s4o.print("0");  /* milliseconds */

   447

  else

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

   449

   450

  s4o.print(", ");

   451

   452

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

   453

  return NULL;

   454

}

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/* SYM_REF2(milliseconds_c, milliseconds, unused) */

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void *visit(milliseconds_c *symbol) {

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  TRACE("milliseconds_c");

   460

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

   461

  return NULL;

   462

}

   463

   464

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

   465

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

   466

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

   467

   468

/* SYM_REF2(time_of_day_c, daytime, unused) */

   469

void *visit(time_of_day_c *symbol) {

   470

  TRACE("time_of_day_c");

   471

  s4o.print("__tod_to_timespec(");

   472

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

   473

  s4o.print(")");

   474

  return NULL;

   475

}

   476

   477

   478

/* SYM_REF4(daytime_c, day_hour, day_minute, day_second, unused) */

   479

void *visit(daytime_c *symbol) {

   480

  TRACE("daytime_c");

   481

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

   482

  s4o.print(", ");

   483

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

   484

  s4o.print(", ");

   485

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

   486

  return NULL;

   487

}

   488

   489

   490

/* SYM_REF2(date_c, date_literal, unused) */

   491

void *visit(date_c *symbol) {

   492

  TRACE("date_c");

   493

  s4o.print("__date_to_timespec(");

   494

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

   495

  s4o.print(")");

   496

  return NULL;

   497

}

   498

   499

   500

/* SYM_REF4(date_literal_c, year, month, day, unused) */

   501

void *visit(date_literal_c *symbol) {

   502

  TRACE("date_literal_c");

   503

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

   504

  s4o.print(", ");

   505

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

   506

  s4o.print(", ");

   507

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

   508

  return NULL;

   509

}

   510

   511

   512

/* SYM_REF2(date_and_time_c, date_literal, daytime) */

   513

void *visit(date_and_time_c *symbol) {

   514

  TRACE("date_and_time_c");

   515

  s4o.print("__dt_to_timespec(");

   516

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

   517

  s4o.print(", ");

   518

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

   519

  s4o.print(")");

   520

  return NULL;

   521

}

   522

   523

   524

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

   525

/* B.1.3 - Data types */

   526