1

/*

     2

 * (c) 2007 Mario de Sousa

     3

 *

     4

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

     5

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

     6

 * License, or (at your option) any later version.

     7

 *

     8

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

     9

 * WITHOUT ANY WARRANTY; without even the implied warranty of

    10

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

    11

 * Public License for more details.

    12

 *

    13

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

    14

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

    15

 */

    16

    17

/*

    18

 * An IEC 61131-3 IL and ST compiler.

    19

 *

    20

 * Based on the

    21

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

    22

 *

    23

 */

    24

    25

    26

/*

    27

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

    28

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

    29

 */

    30

    31

    32

    33

// #include "stage1_2.hh"

    34

#include "iec.y.hh"

    35

#include "stage1_2_priv.hh"

    36

    37

    38

    39

    40

    41

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

    42

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

    43

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

    44

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

    45

 * Note that flex accesses and updates this global variable

    46

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

    47

 * directive...

    48

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

    49

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

    50

 * file being parsed.

    51

 */

    52

const char *current_filename = NULL;

    53

    54

    55

    56

    57

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

    58

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

    59

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

    60

    61

static int goto_body_state__ = 0;

    62

    63

void cmd_goto_body_state(void) {goto_body_state__ = 1;}

    64

int  get_goto_body_state(void) {return goto_body_state__;}

    65

void rst_goto_body_state(void) {goto_body_state__ = 0;}

    66

    67

    68

    69

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

    70

/* The global symbol tables...   */

    71

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

    72

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

    73

 *       through the function get_identifier_token()

    74

 */

    75

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

    76

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

    77

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

    78

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

    79

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

    80

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

    81

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

    82

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

    83

 */ 

    84

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

    85

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

    86

 *       <fb_name , fb_decl>

    87

 *       <type_name , type_decl>

    88

 *       <program_name , program_decl>

    89

 *       <configuration_name , configuration_decl>

    90

 */

    91

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

    92

    93

/* A symbol table to store the declared variables of

    94

 * the function currently being parsed...

    95

 */

    96

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

    97

    98

    99

/* Function only called from within flex!

   100

 *

   101

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

   102

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

   103

 * symbol found.

   104

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

   105

 * does it continue searching in the library elements

   106

 */

   107

int get_identifier_token(const char *identifier_str) {

   108

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

   109

  int token_id;

   110

   111

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

   112

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

   113

      return identifier_token;

   114

  return token_id;

   115

}

   116

   117

   118

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

   119

/* Utility Functions... */

   120

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

   121

   122

/*

   123

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

   124

 */

   125

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

   126

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

   127

   128

  if (!res)

   129

    return NULL;

   130

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

   131

}

   132

   133

/*

   134

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

   135

 */

   136

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

   137

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

   138

   139

  if (!res)

   140

    return NULL;

   141

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

   142

}

   143

   144

   145

   146

   147

   148

   149

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

   150

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

   151

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

   152

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

   153

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

   154

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

   155

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

   156

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

   157

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

   158

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

   159

   160

   161

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

   162

   163

   164

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

   165

  return stage1_2__(filename, includedir, tree_root_ref);

   166

}

   167