1 /*

     2  * (c) 2003 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  * Seperation of type specification and default value constructs

    27  * (for e.g. simple_spec_init_c), into a type specificiation part,

    28  * and a default value part.

    29  */

    30 

    31 #include "spec_init_separator.hh"

    32 

    33 //#define DEBUG

    34 #ifdef DEBUG

    35 #define TRACE(classname) printf("\n____%s____\n",classname);

    36 #else

    37 #define TRACE(classname)

    38 #endif

    39 

    40 #define ERROR error_exit(__FILE__,__LINE__)

    41 /* function defined in main.cc */

    42 extern void error_exit(const char *file_name, int line_no);

    43 

    44 

    45 spec_init_sperator_c *spec_init_sperator_c::get_class_instance(void) {

    46   if (NULL == class_instance)

    47     class_instance = new spec_init_sperator_c();

    48 

    49   if (NULL == class_instance)

    50     ERROR;

    51 

    52   return class_instance;

    53 }

    54 

    55  /* the only two public functions... */

    56 symbol_c *spec_init_sperator_c::get_spec(symbol_c *spec_init) {

    57    search_what = search_spec;

    58    return (symbol_c *)spec_init->accept(*get_class_instance());

    59 }

    60 

    61 symbol_c *spec_init_sperator_c::get_init(symbol_c *spec_init) {

    62    search_what = search_init;

    63    return (symbol_c *)spec_init->accept(*get_class_instance());

    64 }

    65 

    66 /*******************************************/

    67 /* B 1.1 - Letters, digits and identifiers */

    68 /*******************************************/

    69 // SYM_TOKEN(identifier_c)

    70 void *spec_init_sperator_c::visit(identifier_c *symbol) {

    71   TRACE("spec_init_sperator_c::identifier_c");

    72   switch (search_what) {

    73     /* if we ever get called sith a simple identifier_c, then it must be a previously declared type... */

    74     case search_spec: return symbol;

    75     case search_init: return NULL;

    76   }

    77   ERROR; /* should never occur */

    78   return NULL;

    79 }

    80 

    81 

    82 /********************************/

    83 /* B 1.3.3 - Derived data types */

    84 /********************************/

    85 

    86 /* simple_specification ASSIGN constant */

    87 void *spec_init_sperator_c::visit(simple_spec_init_c *symbol) {

    88   TRACE("spec_init_sperator_c::simple_spec_init_c");

    89   switch (search_what) {

    90     case search_spec: return symbol->simple_specification;

    91     case search_init: return symbol->constant;

    92   }

    93   ERROR; /* should never occur */

    94   return NULL;

    95 }

    96 

    97 /* subrange_specification ASSIGN signed_integer */

    98 void *spec_init_sperator_c::visit(subrange_spec_init_c *symbol) {

    99   TRACE("spec_init_sperator_c::subrange_spec_init_c");

   100   switch (search_what) {

   101     case search_spec: return symbol->subrange_specification->accept(*this);

   102     case search_init: return symbol->signed_integer;

   103   }

   104   ERROR; /* should never occur */

   105   return NULL;

   106 }

   107 

   108 /*  integer_type_name '(' subrange')' */

   109 void *spec_init_sperator_c::visit(subrange_specification_c *symbol) {

   110   TRACE("spec_init_sperator_c::subrange_specification_c");

   111   switch (search_what) {

   112     case search_spec: return symbol->integer_type_name;

   113     case search_init: return NULL; /* should never occur */

   114   }

   115   ERROR; /* should never occur */

   116   return NULL;

   117 }

   118 

   119 /* array_specification [ASSIGN array_initialization} */

   120 /* array_initialization may be NULL ! */

   121 void *spec_init_sperator_c::visit(array_spec_init_c *symbol) {

   122   TRACE("spec_init_sperator_c::array_spec_init_c");

   123   switch (search_what) {

   124     case search_spec: return symbol->array_specification;

   125     case search_init: return symbol->array_initialization;

   126   }

   127   return NULL;

   128 }

   129 

   130 /* enumerated_specification ASSIGN enumerated_value */

   131 void *spec_init_sperator_c::visit(enumerated_spec_init_c *symbol) {

   132   TRACE("spec_init_sperator_c::enumerated_spec_init_c");

   133   switch (search_what) {

   134     case search_spec: return symbol->enumerated_specification;

   135     case search_init: return symbol->enumerated_value;

   136   }

   137   ERROR; /* should never occur */

   138   return NULL;

   139 }

   140 

   141 /* structure_type_name ASSIGN structure_initialization */

   142 /* structure_initialization may be NULL ! */

   143 //SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)

   144 void *spec_init_sperator_c::visit(initialized_structure_c *symbol) {

   145   TRACE("spec_init_sperator_c::initialized_structure_c");

   146   switch (search_what) {

   147     case search_spec: return symbol->structure_type_name;

   148     case search_init: return symbol->structure_initialization;

   149   }

   150   ERROR; /* should never occur */

   151   return NULL;

   152 }

   153 

   154 

   155 /******************************************/

   156 /* B 1.4.3 - Declaration & Initialisation */

   157 /******************************************/

   158 

   159 /* fb_name_list ':' function_block_type_name ASSIGN structure_initialization */

   160 /* structure_initialization -> may be NULL ! */

   161 void *spec_init_sperator_c::visit(fb_name_decl_c *symbol) {

   162   TRACE("spec_init_sperator_c::fb_name_decl_c");

   163   switch (search_what) {

   164     case search_spec: return symbol->function_block_type_name;

   165     case search_init: return symbol->structure_initialization;

   166   }

   167   ERROR; /* should never occur */

   168   return NULL;

   169 }

   170 

   171 spec_init_sperator_c *spec_init_sperator_c ::class_instance = NULL;

   172 spec_init_sperator_c::search_what_t spec_init_sperator_c::search_what;