removed temporary hack needed becauseof lacking symbol table, started to add function symbols for internal functions

3 files changed, 84 insertions, 32 deletions

diff --git a/minie/README b/minie/README
index 9ae9438..c8fe74e 100644
--- a/minie/README
+++ b/minie/README
@@ -19,4 +19,4 @@ test2: syntax error, no module definition
 test3: module definition lacking a module name
 test4: general expressions and variables
 test5: basic system input/output, import of pseudo module 'system'
-test6: string functions
+test6: string functions, internal function 'length'
diff --git a/minie/e2c.c b/minie/e2c.c
index 065c4a0..6c358a1 100644
--- a/minie/e2c.c
+++ b/minie/e2c.c
@@ -11,8 +11,9 @@ enum {
 	MAX_NUMBER_LEN = 9,
 	MAX_ERRMSG_LEN = 64,
 	MAX_STRING_LEN = 64,
+	MAX_SYMBOLS = 32,
 	MAX_RECORD_MEMBERS = 8,
-	MAX_SYMBOLS = 32
+	MAX_FUNCTION_PARAMETERS = 4
 };
 
 /* SCANNER */
@@ -414,7 +415,8 @@ typedef enum {
 	TYPE_BYTE,
 	TYPE_CHAR,
 	TYPE_ARRAY,
-	TYPE_RECORD
+	TYPE_RECORD,
+	TYPE_FUNCTION
 } BasicType;
 
 static BasicType strToBasicType( char *name )
@@ -443,11 +445,20 @@ typedef struct RecordType {
 	int len;
 } RecordType;
 
+typedef struct FunctionType {
+	BasicType params[MAX_FUNCTION_PARAMETERS];
+	int len;
+	int internal;
+} FunctionType;
+
 typedef struct Type {
 	BasicType type;
 	char name[MAX_IDENT_LEN];
-	ArrayType array;
-	RecordType record;
+	union {
+		ArrayType array;
+		RecordType record;
+		FunctionType function;
+	} details;
 } Type;
 
 static int nof_symbols = 0;
@@ -475,7 +486,21 @@ static Type get_symbol_type( char *name )
 		}
 	}
 	
-	Abort( "Could not determine type of symbol '%s'", name );
+	Abort( "Unknown symbol '%s'", name );
+}
+
+/* INTERNAL FUNCTIONS */
+
+static int length( char *name )
+{
+	Type type;
+	
+	type = get_symbol_type( name );
+	if( type.type == TYPE_ARRAY ) {
+		return type.details.array.len;
+	} else {
+		Abort( "length called on non-array variable '%s'", name );
+	}
 }
 
 /* PARSER */
@@ -483,7 +508,6 @@ static Type get_symbol_type( char *name )
 static char moduleName[MAX_IDENT_LEN+1];
 static char varName[MAX_IDENT_LEN+1];
 static Type lastType;
-static int isArray = 0;
 static char typeName[MAX_IDENT_LEN+1];
 static char procName[MAX_IDENT_LEN+1];
 
@@ -513,12 +537,26 @@ static void emit( char *s, ... )
 	va_end( args );
 }
 
-static void prologue( void )
+static void register_internal_functions( void )
 {
+	Type type;
+	
+	/* register compiler-internal functions */
+	type.type = TYPE_FUNCTION;
+	type.details.function.len = 1;
+	type.details.function.params[0] = TYPE_ARRAY;
+	type.details.function.internal = 1;
+	insert_symbol( type, "length" );
+}
+
+static void prologue( void )
+{	
 	emitLn( "/* generated with e2c */" );
 	emitLn( "#include <stdio.h>" );
 	emitLn( "#include <stdlib.h>" );
 	emitLn( "#include <string.h>" );
+	
+	register_internal_functions( );
 }
 
 static void init( void )
@@ -569,9 +607,12 @@ static void variableName( void )
 }
 
 static void expression( void );
+static void parameterList( void );
 
 static void factor( void )
 {
+	Type type;
+	
 	if( sym == S_plus ) {
 		sym = getSym( );
 	} else if( sym == S_minus ) {
@@ -585,17 +626,25 @@ static void factor( void )
 		emit( "\"%s\"", str );
 		sym = getSym( );
 	} else if( sym == S_ident ) {
-		/* TODO: hacky, the question is also, should this
-		 * be a keyword
-		 */
-		if( strcmp( ident, "true" ) == 0 ) {
-			emit( "1" );
-		} else if( strcmp( ident, "false" ) == 0 ) {
-			emit( "0" );
+		type = get_symbol_type( ident );
+		if( type.type == TYPE_FUNCTION ) {
+			emit( "%s( ", ident );
+			sym = getSym( );
+			parameterList( );
+			emit( " )" );
 		} else {
-			emit( "%s", ident );
+			/* TODO: hacky, the question is also, should this
+			 * be a keyword
+			 */
+			if( strcmp( ident, "true" ) == 0 ) {
+				emit( "1" );
+			} else if( strcmp( ident, "false" ) == 0 ) {
+				emit( "0" );
+			} else {
+				emit( "%s", ident );
+			}
+			sym = getSym( );
 		}
-		sym = getSym( );
 	} else if( sym == S_lparen ) {
 		emit( "(" );
 		sym = getSym( );
@@ -636,14 +685,14 @@ static void assignment( void )
 	/* precondition: ident is a variable and already parsed */
 	Expect( S_assign );
 	type = get_symbol_type( varName );
-	if( type.type == TYPE_ARRAY && type.array.type == TYPE_CHAR ) {
+	if( type.type == TYPE_ARRAY && type.details.array.type == TYPE_CHAR ) {
 		emit( "strncpy( %s, ", varName );
 	} else {
 		emit( "%s = ", varName );
 	}
 	expression( );
-	if( type.type == TYPE_ARRAY && type.array.type == TYPE_CHAR ) {
-		emit( ", %d )", type.array.len );
+	if( type.type == TYPE_ARRAY && type.details.array.type == TYPE_CHAR ) {
+		emit( ", %d )", type.details.array.len );
 	}
 	emitLn( ";" );
 }
@@ -683,14 +732,21 @@ static void doIf( void )
 
 static void parameterList( void )
 {
+	int n = 0;
+	
 	Expect( S_lparen );
 	if( sym == S_rparen ) {
+		if( strcmp( varName, "length" ) == 0 ) {
+			emit( "%d", length( varName ) );
+		}
 		sym = getSym( );
 		return;
 	}
 	/* TODO: no VAR parameters, strictly pass-by-value */
 	expression( );
+	n = 1;
 	while( sym == S_comma ) {
+		n++;
 		emit( ", " );
 		sym = getSym( );
 		/* TODO: no VAR parameters, strictly pass-by-value */
@@ -719,18 +775,16 @@ static void statement( void )
 			} else if( strcmp( varName, "system.halt" ) == 0 ) {
 				emit( "exit( " );
 			} else if( strcmp( varName, "system.readline" ) == 0 ) {
-				emit( "{ size_t _n = %d; fgets( (char *)&", num );
-			} else if( strcmp( varName, "length" ) == 0 ) {
-				emit( "255" );
+				/* TODO: check if parameter is an array of char,
+				 get length of the defined array and put it into the parameter
+				 of getline */
+				emit( "{ size_t _n = %d; fgets( (char *)&", 255 );
 			} else {
 				emit( "%s( ", varName );
 			}
 			parameterList( );
 			/* TODO: procedure call */
 			if( strcmp( varName, "system.readline" ) == 0 ) {
-				/* TODO: check if parameter is an array of char,
-				 get length of the defined array and put it into the parameter
-				 of getline */
 				emitLn( ", _n, stdin ); }" );
 			} else {
 				emitLn( ");" );
@@ -806,8 +860,8 @@ static void arrayType( void )
 		type( );
 		/* type is in ident */
 		lastType.type = TYPE_ARRAY;
-		lastType.array.type = strToBasicType( ident );
-		lastType.array.len = num;
+		lastType.details.array.type = strToBasicType( ident );
+		lastType.details.array.len = num;
 	} else {
 		Abort( "of' expected in array definition" );			
 	}
@@ -818,10 +872,8 @@ static void type( void )
 	identifier( );
 	if( sym == S_ident ) {
 		simpleType( );
-		isArray = 0;
 	} else if( sym == S_array ) {
 		arrayType( );
-		isArray = 1;
 	}
 }
 
@@ -832,7 +884,7 @@ static void variableDeclaration( void )
 	Expect( S_colon );
 	type( );
 	insert_symbol( lastType, varName );
-	if( isArray ) {
+	if( lastType.type == TYPE_ARRAY ) {
 		emitLn( "static %s %s[%d];", typeName, varName, num );
 	} else {
 		emitLn( "static %s %s;", typeName, varName );
diff --git a/minie/test6.e b/minie/test6.e
index 15e5969..42838ef 100644
--- a/minie/test6.e
+++ b/minie/test6.e
@@ -8,7 +8,7 @@ var
 	
 begin
 	system.readline( s );
-	len := len( s );
+	len := length( s );
 	system.writestring( "String: " );
 	system.writeline( s );
 	system.writestring( "Length: " );