more work on parameter lists, added string parser

2 files changed, 108 insertions, 17 deletions

diff --git a/minie/README b/minie/README
index 28cae32..384afaf 100644
--- a/minie/README
+++ b/minie/README
@@ -6,4 +6,4 @@ gcc -g -O0 -Wall -pedantic -std=c89 -o e2c e2c.c
 
 ./e2c < test4.e > test4.c && gcc -o test4 test4.c && ./test4
 
-
+./e2c < ec.e
diff --git a/minie/e2c.c b/minie/e2c.c
index 869c65c..d2274bf 100644
--- a/minie/e2c.c
+++ b/minie/e2c.c
@@ -2,27 +2,31 @@
 #include <string.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <assert.h>
 
 enum {
 	MAX_IDENT_LEN = 16,
 	MAX_NUMBER_LEN = 9,
-	MAX_ERRMSG_LEN = 64
+	MAX_ERRMSG_LEN = 64,
+	MAX_STRING_LEN = 64
 };
 
 static int look;
 static int row;
 static int col;
+static int num;
+static char str[MAX_STRING_LEN+1];
 static char ident[MAX_IDENT_LEN+1];
 static char moduleName[MAX_IDENT_LEN+1];
 static char varName[MAX_IDENT_LEN+1];
 static char typeName[MAX_IDENT_LEN+1];
 static char procName[MAX_IDENT_LEN+1];
-static int num;
 
 typedef enum {
 	S_char = 0,
 	S_ident,
 	S_number,
+	S_string,
 	S_module,
 	S_begin,
 	S_end,
@@ -32,6 +36,7 @@ typedef enum {
 	S_if,
 	S_do,
 	S_else,
+	S_dot,
 	S_comma,
 	S_semicolon,
 	S_colon,
@@ -49,6 +54,7 @@ char *symname[S_eof+1] = {
 	"char",
 	"ident",
 	"nunber",
+	"string",
 	"module",
 	"begin",
 	"end",
@@ -58,6 +64,7 @@ char *symname[S_eof+1] = {
 	"if",
 	"do",
 	"else",
+	".",
 	",",
 	";",
 	":",
@@ -126,6 +133,22 @@ static int isDigit( int c )
 	return 0;
 }
 
+static int isCharacter( int c )
+{
+	if( isAlpha( c ) ) return 1;
+	if( isDigit( c ) ) return 1;
+	switch( c ) {
+		case ' ':
+		case '[':
+		case ']':
+		/* TODO: allow more characters as we go along */
+			return 1;
+		default:
+			return 0;
+	}
+	return 0;
+}
+
 static void skipWhite( void )
 {	
 	while( isWhite( look ) ) {
@@ -133,7 +156,7 @@ static void skipWhite( void )
 	}
 }
 
-static void identifier( )
+static void identifier( void )
 {
 	int n = 0;
 	if( isAlpha( look ) ) {
@@ -147,13 +170,13 @@ static void identifier( )
 		}
 		ident[n] = '\0';
 		if( n == MAX_IDENT_LEN ) {
-			Abort( "Identifier exceeded maximal length" );
+			Abort( "Identifier exceeds maximal length" );
 		}
 		sym = S_ident;
 	}
 }
 
-static void number( )
+static void number( void )
 {
 	int n = 0;
 	if( isDigit( look ) ) {
@@ -171,10 +194,34 @@ static void number( )
 	}
 }
 
-static Symbol getSym( )
+static void string( void )
+{
+	int n = 0;
+	look = getChar( );
+	while( look != '"' && isCharacter( look ) && n < MAX_STRING_LEN ) {
+		str[n] = look;
+		n++;
+		look = getChar( );
+	}
+	str[n] = '\0';
+	if( n == MAX_STRING_LEN ) {
+		Abort( "String constant exceeds maximal length" );
+	}
+	if( look != '"' ) {
+		Abort( "Unterminated string or illegal character in string" );
+	}
+	sym = S_string;
+	assert( look == '"' );
+	look = getChar( );
+}
+
+
+static Symbol getSym( void )
 {
 	skipWhite( );
+	num = 0;
 	ident[0] = '\0';
+	str[0] = '\0';
 	switch( look ) {
 		case '0':
 		case '1':
@@ -283,6 +330,9 @@ static Symbol getSym( )
 		case 'Z':
 			identifier( );
 			return S_ident;
+		case '"':
+			string( );
+			return S_string;
 		case ':':
 			look = getChar( );
 			if( look == '=' ) {
@@ -293,6 +343,9 @@ static Symbol getSym( )
 		case ';':
 			look = getChar( );
 			return S_semicolon;
+		case '.':
+			look = getChar( );
+			return S_dot;
 		case ',':
 			look = getChar( );
 			return S_comma;
@@ -370,6 +423,26 @@ static void epilogue( void )
 	emitLn( "}" );
 }
 
+static void qualident( void )
+{
+	identifier( );
+	if( sym == S_ident ) {
+		strncpy( varName, ident, MAX_IDENT_LEN );
+		varName[MAX_IDENT_LEN-1] = '\0';
+	}
+	sym = getSym( );
+	if( sym == S_dot ) {
+		sym = getSym( );
+		if( sym == S_ident ) {
+			strncat( varName, ".", MAX_IDENT_LEN );
+			varName[MAX_IDENT_LEN-1] = '\0';
+			strncat( varName, ident, MAX_IDENT_LEN );
+			varName[MAX_IDENT_LEN-1] = '\0';
+			sym = getSym( );
+		}
+	}
+}
+
 static void variableName( void )
 {
 	identifier( );
@@ -392,6 +465,9 @@ static void factor( void )
 	if( sym == S_number ) {
 		emit( "%d", num );		
 		sym = getSym( );
+	} else if( sym == S_string ) {
+		emit( "\"%s\"", str );
+		sym = getSym( );
 	} else if( sym == S_ident ) {
 		/* TODO: hacky */
 		if( strcmp( ident, "true" ) == 0 ) {
@@ -437,9 +513,7 @@ static void expression( void )
 
 static void assignment( void )
 {
-	/* qualident is variableName( ) and has been read already */
-	variableName( );
-	sym = getSym( );
+	/* precondition: ident is a variable and already parsed */
 	Expect( S_assign );
 	emit( "%s = ", varName );
 	expression( );
@@ -479,6 +553,23 @@ static void doIf( void )
 	emitLn( "}" );
 }
 
+static void parameterList( void )
+{
+	Expect( S_lparen );
+	if( sym == S_rparen ) {
+		return;
+	}
+	/* TODO: no VAR parameters, strictly pass-by-value */
+	expression( );
+	sym = getSym( );
+	while( sym == S_comma ) {
+		sym = getSym( );
+		/* TODO: no VAR parameters, strictly pass-by-value */
+		expression( );
+	}
+	Expect( S_rparen );
+}
+
 static void statement( void )
 {	
 	if( sym == S_if ) {
@@ -488,17 +579,17 @@ static void statement( void )
 	} else if( sym == S_end || sym == S_else ) {
 		return;
 	} else if( sym == S_ident ) {
-		assignment( );
+		qualident( );
+		if( sym == S_lparen ) {
+			parameterList( );
+			/* TODO: procedure call */
+		} else {
+			assignment( );
+		}
 	} else {
 		Abort( "Illegal statement" );
 	}
 }
-/*
-QualifiedIdentifier	= Identifier [ "." Identifier ];
-ParameterList		= "(" ")" .
-ProdecureCall		= QualifiedIdentifier ParameterList .
-Statement		= Assignment | IfStatement | ProcedureCall .
-*/
 
 static void statementSequence( void )
 {