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/*

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 * (c) 2007 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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/*

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 * This file contains the code that calls the stage 1 (lexical anayser) 

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 * and stage 2 (syntax parser) during the first pass.

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 */

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/* file with declaration of absyntax classes... */

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#include "../absyntax/absyntax.hh"

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// #include "stage1_2.hh"

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#include "iec.y.hh"

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#include "stage1_2_priv.hh"

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

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/* The name of the file being parsed. */

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

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/* The name of the file currently being parsed...

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 * Note that flex accesses and updates this global variable

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 * apropriately whenever it comes across an (*#include <filename> *)

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 * directive...

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 * ... and bison will use it when producing error messages.

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 * Note that bison also sets this variable correctly to the first

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 * file being parsed.

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 */

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const char *current_filename = NULL;

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

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/* Controlling the entry to the st_il_state in flex. */

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

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static int goto_body_state__ = 0;

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void cmd_goto_body_state(void) {goto_body_state__ = 1;}

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int  get_goto_body_state(void) {return goto_body_state__;}

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void rst_goto_body_state(void) {goto_body_state__ = 0;}

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

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/* The global symbol tables...   */

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

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/* NOTE: only accessed indirectly by the lexical parser (flex)

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 *       through the function get_identifier_token()

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 */

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/* NOTE: BOGUS_TOKEN_ID is defined in the bison generated file iec.y.hh.

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 *       We need this constant defined before we can declare the symbol tables.

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 *       However, we cannot #include "iec.y.hh" in this file (stage1_2_priv.hh) directly

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 *       because of the way bison ver. 3.2 is copying all declarations in the prologue

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 *       of iec.y to the iec.y.hh file (including an #include stage1_2_priv.hh).

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 *       So, if we were to include "iec.y.hh" here, we would get a circular include.

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 *       All this means that whoever includes this file (stage1_2_priv.hh) will need

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 *       to take care to first inlcude iec.y.hh !!

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 */ 

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/* A symbol table to store all the library elements */

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/* e.g.: <function_name , function_decl>

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 *       <fb_name , fb_decl>

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 *       <type_name , type_decl>

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 *       <program_name , program_decl>

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 *       <configuration_name , configuration_decl>

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 */

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/* static */ symtable_c<int, BOGUS_TOKEN_ID> library_element_symtable;

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/* A symbol table to store the declared variables of

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 * the function currently being parsed...

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 */

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/* static */ symtable_c<int, BOGUS_TOKEN_ID> variable_name_symtable;

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/* Function only called from within flex!

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 *

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 * search for a symbol in either of the two symbol tables

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 * declared above, and return the token id of the first

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 * symbol found.

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 * Searches first in the variables, and only if not found

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 * does it continue searching in the library elements

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 */

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int get_identifier_token(const char *identifier_str) {

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//  std::cout << "get_identifier_token(" << identifier_str << "): \n";

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  int token_id;

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  if ((token_id = variable_name_symtable.find_value(identifier_str)) == variable_name_symtable.end_value())

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    if ((token_id = library_element_symtable.find_value(identifier_str)) == library_element_symtable.end_value())

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      return identifier_token;

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  return token_id;

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}

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

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/* Utility Functions... */

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

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/*

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 * Join two strings together. Allocate space with malloc(3).

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 */

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char *strdup2(const char *a, const char *b) {

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  char *res = (char *)malloc(strlen(a) + strlen(b) + 1);

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  if (!res)

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    return NULL;

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  return strcat(strcpy(res, a), b);  /* safe, actually */

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}

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/*

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 * Join three strings together. Allocate space with malloc(3).

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 */

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char *strdup3(const char *a, const char *b, const char *c) {

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  char *res = (char *)malloc(strlen(a) + strlen(b) + strlen(c) + 1);

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  if (!res)

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    return NULL;

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  return strcat(strcat(strcpy(res, a), b), c);  /* safe, actually */

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}

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

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

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

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

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

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

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

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

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

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

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int stage1_2__(const char *filename, const char *includedir, symbol_c **tree_root_ref);

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int stage1_2(const char *filename, const char *includedir, symbol_c **tree_root_ref) {

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  return stage1_2__(filename, includedir, tree_root_ref);

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}

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