1 /*

     2  *  matiec - a compiler for the programming languages defined in IEC 61131-3

     3  *

     4  *  Copyright (C) 2012  Mario de Sousa (msousa@fe.up.pt)

     5  *

     6  *  This program is free software: you can redistribute it and/or modify

     7  *  it under the terms of the GNU General Public License as published by

     8  *  the Free Software Foundation, either version 3 of the License, or

     9  *  (at your option) any later version.

    10  *

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

    12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of

    13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    14  *  GNU General Public License for more details.

    15  *

    16  *  You should have received a copy of the GNU General Public License

    17  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

    18  *

    19  *

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

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

    22  */

    23 

    24 /*

    25  * An IEC 61131-3 compiler.

    26  *

    27  * Based on the

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

    29  *

    30  */

    31 

    32 

    33 /*

    34  *  Search for a specific label in an IL list. 

    35  *

    36  *  when instantiated, must be given a pointer to one of the following

    37  *     - function_declaration_c

    38  *     - function_block_declaration_c

    39  *     - program_declaration_c

    40  *     - instruction_list_c

    41  *

    42  * which is where all calls to search for a specific label will look for said label.

    43  */

    44 

    45 

    46 

    47 #include "absyntax_utils.hh"

    48 

    49 

    50 

    51 /* set to 1 to see debug info during execution */

    52 static int debug = 0;

    53 

    54 search_il_label_c::search_il_label_c(symbol_c *search_scope) {

    55   this->search_scope = search_scope;

    56   this->search_label = NULL;

    57 }

    58 

    59 search_il_label_c::~search_il_label_c(void) {

    60 }

    61 

    62 

    63 il_instruction_c *search_il_label_c::find_label(const char *label) {

    64   return find_label(new identifier_c(label));

    65 }

    66 

    67 

    68 il_instruction_c *search_il_label_c::find_label(symbol_c *label) {

    69   search_label = label;

    70   il_instruction_c *res = (il_instruction_c *)search_scope->accept(*this);

    71   search_label = NULL;

    72   return res;

    73 }

    74 

    75 

    76 /****************************************/

    77 /* B.2 - Language IL (Instruction List) */

    78 /****************************************/

    79 /***********************************/

    80 /* B 2.1 Instructions and Operands */

    81 /***********************************/

    82 

    83 /* | label ':' [il_incomplete_instruction] eol_list */

    84 // SYM_REF2(il_instruction_c, label, il_instruction)

    85 // void *visit(instruction_list_c *symbol);

    86 void *search_il_label_c::visit(il_instruction_c *symbol) {

    87 // printf("search_il_label_c::visit(il_instruction_c *symbol): searching for %s\n", ((identifier_c *)search_label)->value);

    88 	if (NULL != symbol->label)

    89 		if (compare_identifiers(search_label, symbol->label) == 0)

    90 			return symbol;

    91 

    92 	return NULL;

    93 }

    94 

    95 

    96 

    97