/*
* (c) 2003 Mario de Sousa
*
* Offered to the public under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
* Public License for more details.
*
* This code is made available on the understanding that it will not be
* used in safety-critical situations without a full and competent review.
*/
/*
* An IEC 61131-3 IL and ST compiler.
*
* Based on the
* FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
*
*/
/* Determine the data type of a specific variable instance, including
* function block instances.
* A reference to the relevant variable declaration is returned.
* The variable instance may NOT be a member of a structure of a memeber
* of a structure of an element of an array of ...
*
* example:
* window.points[1].coordinate.x
* window.points[1].colour
* etc... ARE NOT ALLOWED!
*
* This class must only be passed the name of the variable that will appear
* in the variable declaration. In the above examples, this would be
* 'window' !!
*
*
* If you need to pass a complete name of a variable instance (such as
* 'window.points[1].coordinate.x') use the search_varfb_instance_type_c instead!
*/
/* Note that current_type_decl that this class returns may reference the
* name of a type, or the type declaration itself!
* For an example of the first, consider a variable declared as ...
* x : AAA;
* where the AAA type is previously declared as whatever.
* For an example of the second, consider a variable declared as ...
* x : array of int [10]; ----> is allowed
*
* If it is the first, we will return a reference to the name, if the second
* we return a reference to the declaration!!
*/
class search_var_instance_decl_c: public search_visitor_c {
private:
symbol_c *search_scope;
symbol_c *search_name;
symbol_c *current_type_decl;
/* variable used to store the type of variable currently being processed... */
/* Will contain a single value of generate_c_vardecl_c::XXXX_vt */
unsigned int current_vartype;
public:
search_var_instance_decl_c(symbol_c *search_scope) {
this->current_vartype = none_vt;
this->search_scope = search_scope;
this->search_name = NULL;
this->current_type_decl = NULL;
}
symbol_c *get_decl(symbol_c *variable_instance_name) {
this->search_name = variable_instance_name;
return (symbol_c *)search_scope->accept(*this);
}
unsigned int get_vartype() {
return current_vartype;
}
public:
/* the types of variables that need to be processed... */
static const unsigned int none_vt = 0x0000;
static const unsigned int input_vt = 0x0001; // VAR_INPUT
static const unsigned int output_vt = 0x0002; // VAR_OUTPUT
static const unsigned int inoutput_vt = 0x0004; // VAR_IN_OUT
static const unsigned int private_vt = 0x0008; // VAR
static const unsigned int temp_vt = 0x0010; // VAR_TEMP
static const unsigned int external_vt = 0x0020; // VAR_EXTERNAL
static const unsigned int global_vt = 0x0040; // VAR_GLOBAL
static const unsigned int located_vt = 0x0080; // VAR <var_name> AT <location>
/***************************/
/* B 0 - Programming Model */
/***************************/
void *visit(library_c *symbol) {
/* we do not want to search multiple declaration scopes,
* so we do not visit all the functions, fucntion blocks, etc...
*/
return NULL;
}
/******************************************/
/* B 1.4.3 - Declaration & Initialisation */
/******************************************/
/* edge -> The F_EDGE or R_EDGE directive */
// SYM_REF2(edge_declaration_c, edge, var1_list)
// TODO
void *visit(input_declarations_c *symbol) {
current_vartype = input_vt;
void *res = symbol->input_declaration_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* VAR_OUTPUT [RETAIN | NON_RETAIN] var_init_decl_list END_VAR */
/* option -> may be NULL ! */
void *visit(output_declarations_c *symbol) {
current_vartype = output_vt;
void *res = symbol->var_init_decl_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* VAR_IN_OUT var_declaration_list END_VAR */
void *visit(input_output_declarations_c *symbol) {
current_vartype = inoutput_vt;
void *res = symbol->var_declaration_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* VAR [CONSTANT] var_init_decl_list END_VAR */
/* option -> may be NULL ! */
/* helper symbol for input_declarations */
void *visit(var_declarations_c *symbol) {
current_vartype = private_vt;
void *res = symbol->var_init_decl_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* VAR RETAIN var_init_decl_list END_VAR */
void *visit(retentive_var_declarations_c *symbol) {
current_vartype = private_vt;
void *res = symbol->var_init_decl_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* VAR [CONSTANT|RETAIN|NON_RETAIN] located_var_decl_list END_VAR */
/* option -> may be NULL ! */
//SYM_REF2(located_var_declarations_c, option, located_var_decl_list)
void *visit(located_var_declarations_c *symbol) {
current_vartype = located_vt;
void *res = symbol->located_var_decl_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */
/* option -> may be NULL ! */
//SYM_REF2(external_var_declarations_c, option, external_declaration_list)
void *visit(external_var_declarations_c *symbol) {
current_vartype = external_vt;
void *res = symbol->external_declaration_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */
/* option -> may be NULL ! */
//SYM_REF2(global_var_declarations_c, option, global_var_decl_list)
void *visit(global_var_declarations_c *symbol) {
current_vartype = global_vt;
void *res = symbol->global_var_decl_list->accept(*this);
if (res == NULL) {
current_vartype = none_vt;
}
return res;
}
/* var1_list is one of the following...
* simple_spec_init_c *
* subrange_spec_init_c *
* enumerated_spec_init_c *
*/
// SYM_REF2(var1_init_decl_c, var1_list, spec_init)
void *visit(var1_init_decl_c *symbol) {
current_type_decl = symbol->spec_init;
return symbol->var1_list->accept(*this);
}
/* var1_list ',' variable_name */
// SYM_LIST(var1_list_c)
void *visit(var1_list_c *symbol) {
list_c *list = symbol;
for(int i = 0; i < list->n; i++) {
if (compare_identifiers(list->elements[i], search_name) == 0)
/* by now, current_type_decl should be != NULL */
return current_type_decl;
}
return NULL;
}
/* name_list ':' function_block_type_name ASSIGN structure_initialization */
/* structure_initialization -> may be NULL ! */
void *visit(fb_name_decl_c *symbol) {
current_type_decl = symbol->function_block_type_name;
return symbol->fb_name_list->accept(*this);
}
/* name_list ',' fb_name */
void *visit(fb_name_list_c *symbol) {
list_c *list = symbol;
for(int i = 0; i < list->n; i++) {
if (compare_identifiers(list->elements[i], search_name) == 0)
/* by now, current_fb_declaration should be != NULL */
return current_type_decl;
}
return NULL;
}
/* var1_list ':' array_spec_init */
// SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)
void *visit(array_var_init_decl_c *symbol) {
current_type_decl = symbol->array_spec_init;
return symbol->var1_list->accept(*this);
}
/* var1_list ':' initialized_structure */
// SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
void *visit(structured_var_init_decl_c *symbol) {
current_type_decl = symbol->initialized_structure;
return symbol->var1_list->accept(*this);
}
/* var1_list ':' array_specification */
// SYM_REF2(array_var_declaration_c, var1_list, array_specification)
void *visit(array_var_declaration_c *symbol) {
current_type_decl = symbol->array_specification;
return symbol->var1_list->accept(*this);
}
/* var1_list ':' structure_type_name */
// SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
void *visit(structured_var_declaration_c *symbol) {
current_type_decl = symbol->structure_type_name;
return symbol->var1_list->accept(*this);
}
/* [variable_name] location ':' located_var_spec_init */
/* variable_name -> may be NULL ! */
// SYM_REF4(located_var_decl_c, variable_name, location, located_var_spec_init, unused)
// TODO!!
/* global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
// SYM_REF2(external_declaration_c, global_var_name, specification)
void *visit(external_declaration_c *symbol) {
if (compare_identifiers(symbol->global_var_name, search_name) == 0)
return symbol->specification;
return NULL;
}
/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
/* type_specification ->may be NULL ! */
// SYM_REF2(global_var_decl_c, global_var_spec, type_specification)
void *visit(global_var_decl_c *symbol) {
if (symbol->type_specification != NULL) {
current_type_decl = symbol->type_specification;
return symbol->global_var_spec->accept(*this);
}
else
return NULL;
}
/*| global_var_name location */
//SYM_REF2(global_var_spec_c, global_var_name, location)
void *visit(global_var_spec_c *symbol) {
if (symbol->global_var_name != NULL && compare_identifiers(symbol->global_var_name, search_name) == 0)
return current_type_decl;
else
return symbol->location->accept(*this);
}
/*| global_var_list ',' global_var_name */
//SYM_LIST(global_var_list_c)
void *visit(global_var_list_c *symbol) {
list_c *list = symbol;
for(int i = 0; i < list->n; i++) {
if (compare_identifiers(list->elements[i], search_name) == 0)
/* by now, current_type_decl should be != NULL */
return current_type_decl;
}
return NULL;
}
/* [variable_name] location ':' located_var_spec_init */
/* variable_name -> may be NULL ! */
//SYM_REF4(located_var_decl_c, variable_name, location, located_var_spec_init, unused)
void *visit(located_var_decl_c *symbol) {
if (symbol->variable_name != NULL && compare_identifiers(symbol->variable_name, search_name) == 0) {
return symbol->located_var_spec_init;
}
else
return NULL;
}
/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
/* type_specification ->may be NULL ! */
// SYM_REF2(global_var_decl_c, global_var_spec, type_specification)
// TODO!!
/*| global_var_name location */
// SYM_REF2(global_var_spec_c, global_var_name, location)
// TODO!!
/* AT direct_variable */
// SYM_REF2(location_c, direct_variable, unused)
// TODO!!
/*| global_var_list ',' global_var_name */
// SYM_LIST(global_var_list_c)
// TODO!!
/* var1_list ':' single_byte_string_spec */
// SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)
void *visit(single_byte_string_var_declaration_c *symbol) {
current_type_decl = symbol->single_byte_string_spec;
return symbol->var1_list->accept(*this);
}
/* STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */
/* integer ->may be NULL ! */
/* single_byte_character_string ->may be NULL ! */
// SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)
// TODO!!
/* var1_list ':' double_byte_string_spec */
// SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)
void *visit(double_byte_string_var_declaration_c *symbol) {
current_type_decl = symbol->double_byte_string_spec;
return symbol->var1_list->accept(*this);
}
/* WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */
/* integer ->may be NULL ! */
/* double_byte_character_string ->may be NULL ! */
// SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)
// TODO!!
/* variable_name incompl_location ':' var_spec */
// SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)
// TODO!!
/* AT incompl_location_token */
// SYM_TOKEN(incompl_location_c)
// TODO!!
/**************************************/
/* B.1.5 - Program organization units */
/**************************************/
/***********************/
/* B 1.5.1 - Functions */
/***********************/
// SYM_REF4(function_declaration_c, derived_function_name, type_name, var_declarations_list, function_body)
void *visit(function_declaration_c *symbol) {
/* functions have a variable named after themselves, to store
* the variable that will be returned!!
*/
if (compare_identifiers(symbol->derived_function_name, search_name) == 0)
return symbol->type_name;
/* no need to search through all the body, so we only
* visit the variable declarations...!
*/
return symbol->var_declarations_list->accept(*this);
}
/*****************************/
/* B 1.5.2 - Function Blocks */
/*****************************/
void *visit(function_block_declaration_c *symbol) {
/* no need to search through all the body, so we only
* visit the variable declarations...!
*/
return symbol->var_declarations->accept(*this);
}
/**********************/
/* B 1.5.3 - Programs */
/**********************/
void *visit(program_declaration_c *symbol) {
/* no need to search through all the body, so we only
* visit the variable declarations...!
*/
return symbol->var_declarations->accept(*this);
}
/********************************/
/* B 1.7 Configuration elements */
/********************************/
/*
CONFIGURATION configuration_name
optional_global_var_declarations
(resource_declaration_list | single_resource_declaration)
optional_access_declarations
optional_instance_specific_initializations
END_CONFIGURATION
*/
/*
SYM_REF6(configuration_declaration_c, configuration_name, global_var_declarations, resource_declarations, access_declarations, instance_specific_initializations, unused)
*/
void *visit(configuration_declaration_c *symbol) {
/* no need to search through all the configuration, so we only
* visit the global variable declarations...!
*/
if (symbol->global_var_declarations != NULL)
return symbol->global_var_declarations->accept(*this);
else
return NULL;
}
/*
RESOURCE resource_name ON resource_type_name
optional_global_var_declarations
single_resource_declaration
END_RESOURCE
*/
// SYM_REF4(resource_declaration_c, resource_name, resource_type_name, global_var_declarations, resource_declaration)
void *visit(resource_declaration_c *symbol) {
/* no need to search through all the resource, so we only
* visit the global variable declarations...!
*/
if (symbol->global_var_declarations != NULL)
return symbol->global_var_declarations->accept(*this);
else
return NULL;
}
/* task_configuration_list program_configuration_list */
// SYM_REF2(single_resource_declaration_c, task_configuration_list, program_configuration_list)
void *visit(single_resource_declaration_c *symbol) {
/* no need to search through all the resource,
* and there is no global variable declarations...!
*/
return NULL;
}
#if 0
/*********************/
/* B 1.4 - Variables */
/*********************/
SYM_REF2(symbolic_variable_c, var_name, unused)
/********************************************/
/* B.1.4.1 Directly Represented Variables */
/********************************************/
SYM_TOKEN(direct_variable_c)
/*************************************/
/* B.1.4.2 Multi-element Variables */
/*************************************/
/* subscripted_variable '[' subscript_list ']' */
SYM_REF2(array_variable_c, subscripted_variable, subscript_list)
/* subscript_list ',' subscript */
SYM_LIST(subscript_list_c)
/* record_variable '.' field_selector */
/* WARNING: input and/or output variables of function blocks
* may be accessed as fields of a tructured variable!
* Code handling a structured_variable_c must take
* this into account!
*/
SYM_REF2(structured_variable_c, record_variable, field_selector)
#endif
};