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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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 *

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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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#include <string.h>

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#include <stdlib.h>

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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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/* whether we are suporting safe extensions           */

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/* as defined in PLCopen - Technical Committee 5      */

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/* Safety Software Technical Specification,           */

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/* Part 1: Concepts and Function Blocks,              */

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/* Version 1.0 – Official Release                     */

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

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bool safe_extensions_ = false;

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bool get_opt_safe_extensions() {return safe_extensions_;}

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

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/* Controlling the entry to the body_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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/* Controlling the entry to the sfc_qualifier_state in flex. */

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

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static int goto_sfc_qualifier_state__ = 0;

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void cmd_goto_sfc_qualifier_state(void) {goto_sfc_qualifier_state__ = 1;}

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int  get_goto_sfc_qualifier_state(void) {return goto_sfc_qualifier_state__;}

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void rst_goto_sfc_qualifier_state(void) {goto_sfc_qualifier_state__ = 0;}

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

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

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

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static int goto_sfc_priority_state__ = 0;

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void cmd_goto_sfc_priority_state(void) {goto_sfc_priority_state__ = 1;}

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int  get_goto_sfc_priority_state(void) {return goto_sfc_priority_state__;}

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void rst_goto_sfc_priority_state(void) {goto_sfc_priority_state__ = 0;}

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

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

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

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static int goto_task_init_state__ = 0;

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void cmd_goto_task_init_state(void) {goto_task_init_state__ = 1;}

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int  get_goto_task_init_state(void) {return goto_task_init_state__;}

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void rst_goto_task_init_state(void) {goto_task_init_state__ = 0;}

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

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/* Returning to state in flex previously pushed onto the stack. */

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

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static int pop_state__ = 0;

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void cmd_pop_state(void) {pop_state__ = 1;}

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int  get_pop_state(void) {return pop_state__;}

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void rst_pop_state(void) {pop_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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/* A symbol table to store the declared direct 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> direct_variable_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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/* Function only called from within flex!

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 *

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 * search for a symbol in direct variables symbol table

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

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 * symbol found.

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 */

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int get_direct_variable_token(const char *direct_variable_str) {

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  int token_id;

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  if ((token_id = direct_variable_symtable.find_value(direct_variable_str)) == direct_variable_symtable.end_value())

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    return direct_variable_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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/* Tracking Functions... */

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

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extern tracking_t* current_tracking;

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/*--------------------------------------------------------------------

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 * GetNextChar

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 * 

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 * reads a character from input for flex

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 *------------------------------------------------------------------*/

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int GetNextChar(char *b, int maxBuffer) {

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  char *p;

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  if (  current_tracking->eof  )

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    return 0;

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  while (  current_tracking->currentChar >= current_tracking->lineLength  ) {

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    current_tracking->currentChar = 0;

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    current_tracking->currentTokenStart = 1;

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    current_tracking->eof = false;

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    p = fgets(current_tracking->buffer, MAX_BUFFER_LENGTH, current_tracking->in_file);

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    if (  p == NULL  ) {

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      if (  ferror(current_tracking->in_file)  )

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        return 0;

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      current_tracking->eof = true;

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      return 0;

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    }

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    current_tracking->lineNumber++;

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    current_tracking->lineLength = strlen(current_tracking->buffer);

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  }

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  b[0] = current_tracking->buffer[current_tracking->currentChar];

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  if (b[0] == ' ' || b[0] == '\t')

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    current_tracking->currentTokenStart++;

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  current_tracking->currentChar++;

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  return b[0]==0?0:1;

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}

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tracking_t* GetNewTracking(FILE* in_file) {

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  tracking_t* new_env = new tracking_t;

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  new_env->eof = 0;

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  new_env->lineNumber = 0;

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  new_env->currentChar = 0;

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  new_env->lineLength = 0;

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  new_env->currentTokenStart = 0;

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  new_env->buffer = (char*)malloc(MAX_BUFFER_LENGTH);

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  new_env->in_file = in_file;

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  return new_env;

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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 stage2__(const char *filename, 

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             const char *includedir,     /* Include directory, where included files will be searched for... */

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             symbol_c **tree_root_ref,

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             bool full_token_loc         /* error messages specify full token location */

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            );

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int stage1_2(const char *filename, symbol_c **tree_root_ref, stage1_2_options_t options) {

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      /* NOTE: we only call stage2 (bison - syntax analysis) directly, as stage 2 will itself call stage1 (flex - lexical analysis)

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       *       automatically as needed

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       */

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      /* NOTE: Since we do not call stage1__ (flex) directly, we cannot directly pass any parameters to that function either.

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       *       In this case, we use callback functions, i.e. stage1__ (i.e. flex) will call functions defined in this file

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       *       whenever it needs info/parameters coming from stage1_2().

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       *       These callback functions will get their data from local (to this file) global variables...

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       *       We now set those variables...

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       */

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  safe_extensions_ = options.safe_extensions;

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  return stage2__(filename, options.includedir, tree_root_ref, options.full_token_loc);

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}

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