--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/absyntax_utils/function_param_iterator.hh Mon Jun 01 21:08:44 2009 +0200
@@ -0,0 +1,322 @@
+/*
+ * (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)
+ *
+ */
+
+
+/*
+ * Function parameter iterator.
+ * Iterate through the in/out parameters of a function declaration.
+ * Function blocks are also suported.
+ *
+ * This is part of the 4th stage that generates
+ * a c++ source program equivalent to the IL and ST
+ * code.
+ */
+
+/* Given a function_declaration_c, iterate through each
+ * function in/out/inout parameter, returning the name
+ * of each parameter...function_param_iterator_c
+ */
+
+
+#include "../absyntax/visitor.hh"
+
+
+class function_param_iterator_c : public null_visitor_c {
+ public:
+ /* A type to specify the type of parameter.
+ * VAR_INPUT => direction_in
+ * VAR_OUTPUT => direction_out
+ * VAR_IN_OUT => direction_inout
+ * VAR_EXTERNAL => direction_extref
+ *
+ * Note that VAR_EXTERNAL declares variables that are in reality references
+ * to global variables. This is used only inside programs!
+ * These references to external variables must be correctly initialised to refer
+ * to the correct global variable. Note that the user may define which variable is to be
+ * referenced in a CONFIGURATION, and that different instantiations of a program
+ * may have the same external variable reference diffenrent global variables!
+ * The references must therefore be correctly initialised when the program instance
+ * is created. This may be done by the PROGRAM class constructor since the ST and IL
+ * languages do not allow the VAR_EXTERNAL reference to change at runtime
+ * for a specific instance.
+ *
+ * We therefore need to call a PROGRAM class constructor with the variables
+ * that should be refernced by the VAR_EXTERNAL variables. The direction_extref will
+ * be used to identify these parameters!
+ */
+ typedef enum {direction_in, direction_out, direction_inout, direction_extref} param_direction_t ;
+
+
+ private:
+ /* a pointer to the function_block_declaration_c
+ * or function_declaration_c currently being analysed.
+ */
+ symbol_c *f_decl;
+ int next_param, param_count;
+ identifier_c *current_param_name;
+ symbol_c *current_param_type;
+ symbol_c *current_param_default_value;
+ param_direction_t current_param_direction;
+ bool en_declared;
+ bool eno_declared;
+
+ private:
+ void* handle_param_list(list_c *list);
+ void* handle_single_param(symbol_c *var_name);
+
+ void* iterate_list(list_c *list);
+
+ public:
+ /* start off at the first parameter once again... */
+ void reset(void);
+
+ /* initialise the iterator object.
+ * We must be given a reference to the function declaration
+ * that will be analysed...
+ */
+ function_param_iterator_c(function_declaration_c *f_decl);
+
+ /* initialise the iterator object.
+ * We must be given a reference to the function block declaration
+ * that will be analysed...
+ */
+ function_param_iterator_c(function_block_declaration_c *fb_decl);
+
+ /* initialise the iterator object.
+ * We must be given a reference to the program declaration
+ * that will be analysed...
+ */
+ function_param_iterator_c(program_declaration_c *p_decl);
+
+ /* Skip to the next parameter. After object creation,
+ * the object references on parameter _before_ the first, so
+ * this function must be called once to get the object to
+ * reference the first parameter...
+ *
+ * Returns the parameter's name!
+ */
+ identifier_c *next(void);
+
+ identifier_c *declare_en_param(void);
+
+ identifier_c *declare_eno_param(void);
+
+ /* Returns the currently referenced parameter's default value,
+ * or NULL if none is specified in the function declrataion itself.
+ */
+ symbol_c *default_value(void);
+
+ /* Returns the currently referenced parameter's type name. */
+ symbol_c *param_type(void);
+
+ /* Returns the currently referenced parameter's data passing direction.
+ * i.e. VAR_INPUT, VAR_OUTPUT or VAR_INOUT
+ */
+ param_direction_t param_direction(void);
+
+ private:
+ /******************************************/
+ /* B 1.4.3 - Declaration & Initialisation */
+ /******************************************/
+ void *visit(input_declarations_c *symbol);
+
+ void *visit(input_declaration_list_c *symbol);
+
+ void *visit(edge_declaration_c *symbol);
+ void *visit(en_param_declaration_c *symbol);
+ /* 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);
+
+ /* var1_list ':' initialized_structure */
+ //SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
+ void *visit(structured_var_init_decl_c *symbol);
+
+#if 0
+/* name_list ':' function_block_type_name ASSIGN structure_initialization */
+/* structure_initialization -> may be NULL ! */
+SYM_REF4(fb_name_decl_c, fb_name_list, function_block_type_name, structure_initialization, unused)
+
+/* name_list ',' fb_name */
+SYM_LIST(fb_name_list_c)
+#endif
+
+ void *visit(output_declarations_c *symbol);
+ void *visit(eno_param_declaration_c *symbol);
+ void *visit(input_output_declarations_c *symbol);
+ void *visit(var_declaration_list_c *symbol);
+
+
+ /* var1_list ':' array_specification */
+ //SYM_REF2(array_var_declaration_c, var1_list, array_specification)
+ void *visit(array_var_declaration_c *symbol);
+
+ /* var1_list ':' structure_type_name */
+ //SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
+ void *visit(structured_var_declaration_c *symbol);
+
+ /* VAR [CONSTANT] var_init_decl_list END_VAR */
+ void *visit(var_declarations_c *symbol);
+
+#if 0
+/* VAR RETAIN var_init_decl_list END_VAR */
+SYM_REF2(retentive_var_declarations_c, var_init_decl_list, unused)
+
+/* 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)
+
+/* helper symbol for located_var_declarations */
+/* located_var_decl_list located_var_decl ';' */
+SYM_LIST(located_var_decl_list_c)
+
+/* [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)
+#endif
+
+ /*| 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);
+
+ /* helper symbol for external_var_declarations */
+ /*| external_declaration_list external_declaration';' */
+ // SYM_LIST(external_declaration_list_c)
+ void *visit(external_declaration_list_c *symbol);
+
+ /* 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 0
+/*| 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)
+
+/* helper symbol for global_var_declarations */
+/*| global_var_decl_list global_var_decl ';' */
+SYM_LIST(global_var_decl_list_c)
+
+/*| 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)
+
+/*| global_var_name location */
+SYM_REF2(global_var_spec_c, global_var_name, location)
+
+/* AT direct_variable */
+SYM_REF2(location_c, direct_variable, unused)
+
+/*| global_var_list ',' global_var_name */
+SYM_LIST(global_var_list_c)
+
+/* var1_list ':' single_byte_string_spec */
+SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)
+
+/* 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)
+
+/* var1_list ':' double_byte_string_spec */
+SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)
+
+/* 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)
+
+/*| VAR [RETAIN|NON_RETAIN] incompl_located_var_decl_list END_VAR */
+/* option ->may be NULL ! */
+SYM_REF2(incompl_located_var_declarations_c, option, incompl_located_var_decl_list)
+
+/* helper symbol for incompl_located_var_declarations */
+/*| incompl_located_var_decl_list incompl_located_var_decl ';' */
+SYM_LIST(incompl_located_var_decl_list_c)
+
+/* variable_name incompl_location ':' var_spec */
+SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)
+
+/* AT incompl_location_token */
+SYM_TOKEN(incompl_location_c)
+#endif
+
+
+ void *visit(var1_init_decl_c *symbol);
+ void *visit(var1_list_c *symbol);
+ void *visit(var_init_decl_list_c *symbol);
+
+
+ /***********************/
+ /* B 1.5.1 - Functions */
+ /***********************/
+ void *visit(function_declaration_c *symbol);
+ /* intermediate helper symbol for function_declaration */
+ void *visit(var_declarations_list_c *symbol);
+ void *visit(function_var_decls_c *symbol);
+
+
+ /*****************************/
+ /* B 1.5.2 - Function Blocks */
+ /*****************************/
+ /* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
+ void *visit(function_block_declaration_c *symbol);
+
+ /* intermediate helper symbol for function_declaration */
+ /* { io_var_declarations | other_var_declarations } */
+ /*
+ * NOTE: we re-use the var_declarations_list_c
+ */
+
+ /* VAR_TEMP temp_var_decl_list END_VAR */
+ void *visit(temp_var_decls_c *symbol);
+ void *visit(temp_var_decls_list_c *symbol);
+
+ /* VAR NON_RETAIN var_init_decl_list END_VAR */
+ void *visit(non_retentive_var_decls_c *symbol);
+
+
+ /**********************/
+ /* B 1.5.3 - Programs */
+ /**********************/
+ /* PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */
+ // SYM_REF4(program_declaration_c, program_type_name, var_declarations, function_block_body, unused)
+ void *visit(program_declaration_c *symbol);
+
+ /* intermediate helper symbol for program_declaration_c */
+ /* { io_var_declarations | other_var_declarations } */
+ /*
+ * NOTE: we re-use the var_declarations_list_c
+ */
+
+}; // function_param_iterator_c
+
+
+
+
+
+
+