Started implementation of function parsing

function.cpp

@@ -0,0 +1,57 @@
+#include "function.h"
+#include <string>
+#include <vector>
+
+struct t_parameter {
+    std::string name;
+    uint32_t    type;
+};
+
+struct t_function {
+    std::string name;
+    uint32_t    address;
+    uint32_t    type;
+    std::vector<t_parameter> parameters;
+};
+
+static std::vector<t_function> functions;
+static int current_function = -1;
+
+const bool function_register(const std::string name, const uint32_t address) {
+    for (auto f : functions) if (f.name == name) return false;
+    functions.push_back({name, address});
+    current_function = functions.size()-1;
+    return true;
+}
+
+void function_set_type(const uint32_t type) {
+    functions[current_function].type = type;
+}
+
+const int function_get_type() {
+    return functions[current_function].type;
+}
+
+const bool function_parameter_add(const std::string name, const uint32_t type) {
+    for (auto p : functions[current_function].parameters) if (p.name == name) return false;
+    functions[current_function].parameters.push_back({name, type});
+    return true;
+}
+
+const bool function_exists(const std::string name) {
+    for (auto f : functions) if (f.name == name) return true;
+    return false;
+}
+
+const uint32_t function_get_address(const std::string name) {
+    for (auto f : functions) if (f.name == name) return f.address;
+    return 0;
+}
+
+const int function_get_num_parameters() {
+    return functions[current_function].parameters.size();
+}
+
+const int function_get_parameter_type(const int index) {
+    return functions[current_function].parameters[index].type;
+}

function.h

@@ -5,8 +5,17 @@
 // Register a new function. Returns false if a function with the same name already exists
 const bool function_register(const std::string name, const uint32_t address);
 
-// Add a parameter to the last registered function
-void function_parameter_add(const std::string name, const int type);
+// Set the return type of the last searched function
+void function_set_type(const uint32_t type);
+
+// Get the return type of the last searched function or -1 if none
+const int function_get_type();
+
+// Add a parameter to the last registered function, returns false if there's a parameter already named like that
+const bool function_parameter_add(const std::string name, const uint32_t type);
+
+// Check if there's a function with that name
+const bool function_exists(const std::string name);
 
 
 // Retrieve the address of the specified function, or zero if there's no such function

parser.cpp

@@ -2,11 +2,13 @@
 #include "tokenizer.h"
 #include "scope.h"
 #include "types.h"
+#include "function.h"
 #include "error.h"
 #include <stdint.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <stack>
 
 #define MAX_CODE_SIZE			65536
 #define MAX_LABELS				256
@@ -417,6 +419,7 @@ static void parse_expression() {
 static bool identifier_exists(const std::string identifier) {
 	if (scope_variable_exists(identifier)) return true;
 	if (types_exist(identifier) != -1) return true;
+	if (function_exists(identifier)) return true;
 	return false;
 }
 
@@ -474,8 +477,7 @@ static void parse_var() {
 
 static void parse_struct() {
 	EXPECT(TOKEN_IDENTIFIER, "Expected identifier");
-	char struct_name[40];
-	strcpy(struct_name, tkn_get_string());
+	const std::string struct_name = tkn_get_string();
 	if (identifier_exists(struct_name)) HALT("Identifier already exists");
 	const int struct_num = types_add(struct_name);
 	tkn_next();
@@ -485,7 +487,6 @@ static void parse_struct() {
 		char member_name[40];
 		strcpy(member_name, tkn_get_string());
 		tkn_next(); EXPECT(TOKEN_AS, "Expected 'as'");
-		// TODO [RZC 04/05/2021] Implement support for arrays
 		tkn_next();
 		if (tkn_get_token() == TOKEN_ARRAY) {
 			tkn_next(); EXPECT(TOKEN_OF, "Expected 'of'");
@@ -495,8 +496,7 @@ static void parse_struct() {
 			tkn_next(); 
 		}
 		EXPECT(TOKEN_IDENTIFIER, "Expected type identifier");
-		char type_name[40];
-		strcpy(type_name, tkn_get_string());
+		const std::string type_name = tkn_get_string();
 		const int type_num = types_exist(type_name);
 		if (type_num == -1) HALT("Unknown type");
 		types_add_member(struct_num, member_name, type_num, member_length);
@@ -505,6 +505,51 @@ static void parse_struct() {
 	tkn_next();
 }
 
+static void parse_function() {
+	EXPECT(TOKEN_IDENTIFIER, "Expected identifier");
+	const std::string function_name = tkn_get_string();
+	if (identifier_exists(function_name)) HALT("Identifier already exists");
+	function_register(function_name, codepos);
+	tkn_next(); EXPECT(TOKEN_LPAR, "Expected '('");
+	tkn_next();
+	scope_open_local();
+	std::stack<uint32_t> addresses;
+	while (tkn_get_token() != TOKEN_RPAR) {
+		if (function_get_num_parameters() != 0) {
+			EXPECT(TOKEN_COMMA, "Expected ',' or ')'");
+			tkn_next();
+		}
+		EXPECT(TOKEN_IDENTIFIER, "Expected identifier");
+		const std::string param_name = tkn_get_string();
+		tkn_next(); EXPECT(TOKEN_AS, "Expected 'as'");
+		tkn_next(); EXPECT(TOKEN_IDENTIFIER, "Expected type identifier");
+		const std::string type_name = tkn_get_string();
+		const int type_num = types_exist(type_name);
+		if (type_num == -1) HALT("Unknown type");
+		if (!function_parameter_add(param_name, type_num)) HALT("Parameter name already used");
+		addresses.push(scope_declare_variable(param_name, type_num, 1));
+		tkn_next();
+	}
+	while (!addresses.empty()) {
+		emmit(OP_STL);
+		emmit_dw(addresses.top());
+		addresses.pop();
+	}
+	tkn_next();
+	if (tkn_get_token() == TOKEN_AS) {
+		tkn_next(); EXPECT(TOKEN_IDENTIFIER, "Expected type identifier");
+		const std::string type_name = tkn_get_string();
+		const int type_num = types_exist(type_name);
+		if (type_num == -1) HALT("Unknown type");
+		function_set_type(type_num);
+		tkn_next();
+	}
+	parse_statements();
+	scope_close_local();
+	EXPECT(TOKEN_END, "Expected statement or 'end'");
+	tkn_next();
+}
+
 /*static void parse_dim() {
 	EXPECT(TOKEN_IDENTIFIER, "Expected variable");
 	char varname[40];
@@ -703,12 +748,19 @@ static void parse_gosub() {
 	tkn_next();
 }*/
 
-/*
+
 static void parse_return() {
-	// TODO [RZC 27/04/2021] Falta afegir paràmetre de retorn
+	const int return_type = function_get_type();
+	if (return_type != -1) {
+		if (return_type == 0) {
+			parse_expression();
+		} else if (return_type == 1) {
+			// TODO [RZC 04/05/2021] Falta gestionar tipus string
+		}
+	}
 	emmit(OP_RET);
 }
-*/
+
 
 // XXX [RZC 27/04/2021] No hi ha labels
 /*static void parse_label() {
@@ -737,21 +789,16 @@ static void parse_call() {
 		}
 	}
 }
-
+*/
 static void parse_statements() {
 	while (!parser_finished) {
 		current_line = tkn_get_line();
 		switch (tkn_get_token()) {
 		case TOKEN_CONST:
 			tkn_next(); parse_const(); break;
-		case TOKEN_DIM:
-			tkn_next(); parse_dim(); break;
-		case TOKEN_LET:
-			tkn_next(); parse_let(); break;
-		case TOKEN_INC:
-			tkn_next(); parse_inc(); break;
-		case TOKEN_DEC:
-			tkn_next(); parse_dec(); break;
+		case TOKEN_VAR:
+			tkn_next(); parse_var(); break;
+/*
 		case TOKEN_IF:
 			tkn_next(); parse_if(); break;
 		case TOKEN_FOR:
@@ -760,23 +807,25 @@ static void parse_statements() {
 			tkn_next(); parse_break(); break;
 		case TOKEN_CONTINUE:
 			tkn_next(); parse_continue(); break;
+*/
 		case TOKEN_RETURN:
 			tkn_next(); parse_return(); break;
 		case TOKEN_REM:
 			tkn_next(); break;
 
+/*
 		case TOKEN_IDENTIFIER:
 			for (int i = 0; i < num_external_functions; i++) {
 				if (strcmp(external_functions[i].name, tkn_get_string()) == 0) { parse_call(); break; }
 			}
 			parse_let(); break;
+*/
 		default:
 			return;
 		}
 	}
 }
 
-*/
 static void parse_global_statements() {
 	while (!parser_finished) {
 		current_line = tkn_get_line();
@@ -787,8 +836,8 @@ static void parse_global_statements() {
 			tkn_next(); parse_var(); break;
 		case TOKEN_STRUCT:
 			tkn_next(); parse_struct(); break;
-		/*case TOKEN_FUNCTION:
-			tkn_next(); parse_function(); break;*/
+		case TOKEN_FUNCTION:
+			tkn_next(); parse_function(); break;
 		case TOKEN_REM:
 			tkn_next(); break;
 		case TOKEN_ENDFILE:

scope.cpp

@@ -30,6 +30,7 @@ const bool scope_is_local() {
 
 void scope_open_local() {
     are_we_inside_local = true;
+    blocks.push(0);
 }
 
 const int scope_close_local() {
@@ -37,6 +38,7 @@ const int scope_close_local() {
         // Malament, no havem tancat algún block. No se si es detectarà abans per altra part. Per ara anem a deixar este comentari.
     }
     const int return_value = local.total_size;
+    while (!blocks.empty()) blocks.pop();
     local.variables.clear();
     local.total_size = 0;
     are_we_inside_local = false;

test.vb

@@ -12,3 +12,8 @@ end
 
 var peiv as array of 2 triangle
 const perico as number = 4-peiv[1].a.x * peiv[0].c.y[2]
+
+function tarari(a as number, b as number) as number
+    var x as number
+end
+