1.1 --- a/src/main.c	Sun Mar 15 13:48:04 2015 +0200
     1.2 +++ b/src/main.c	Mon Mar 16 00:13:54 2015 +0200
     1.3 @@ -12,11 +12,16 @@
     1.4  };
     1.5  
     1.6  void init(void);
     1.7 +void program(void);
     1.8 +void block(void);
     1.9 +void doif(void);
    1.10 +void dowhile(void);
    1.11 +void condition(void);
    1.12  void expression(void);
    1.13  void assignment(void);
    1.14  void term(void);
    1.15  void factor(void);
    1.16 -void ident();
    1.17 +void ident(void);
    1.18  void add(void);
    1.19  void sub(void);
    1.20  void mul(void);
    1.21 @@ -33,6 +38,10 @@
    1.22  void emitln(const char *fmt, ...);
    1.23  int is_addsub(char c);
    1.24  int add_symbol(char c, int type);
    1.25 +int newlabel(void);
    1.26 +const char *labelstr(int lb);
    1.27 +void postlabel(int lb);
    1.28 +void other(void);
    1.29  
    1.30  FILE *infile, *outfile;
    1.31  char look;
    1.32 @@ -60,10 +69,7 @@
    1.33  	/* output prologue */
    1.34  	fputs(prologue, outfile);
    1.35  
    1.36 -	assignment();
    1.37 -	if(look != '\n') {
    1.38 -		expected("newline");
    1.39 -	}
    1.40 +	program();
    1.41  
    1.42  	/* output epilogue */
    1.43  	fputs(epilogue, outfile);
    1.44 @@ -86,6 +92,84 @@
    1.45  	skip_white();
    1.46  }
    1.47  
    1.48 +void program(void)
    1.49 +{
    1.50 +	block();
    1.51 +	if(look != 'e') {
    1.52 +		expected("End");
    1.53 +	}
    1.54 +	emitln("# END");
    1.55 +}
    1.56 +
    1.57 +void other(void)
    1.58 +{
    1.59 +	emitln("%c", get_name());
    1.60 +}
    1.61 +
    1.62 +void block(void)
    1.63 +{
    1.64 +	while(look != 'e' && look != 'l') {
    1.65 +		switch(look) {
    1.66 +		case 'i':
    1.67 +			doif();
    1.68 +			break;
    1.69 +
    1.70 +		case 'w':
    1.71 +			dowhile();
    1.72 +			break;
    1.73 +
    1.74 +		default:
    1.75 +			other();
    1.76 +			break;
    1.77 +		}
    1.78 +	}
    1.79 +}
    1.80 +
    1.81 +void doif(void)
    1.82 +{
    1.83 +	int lb1, lb2;
    1.84 +
    1.85 +	match('i');
    1.86 +	condition();
    1.87 +
    1.88 +	lb1 = newlabel();
    1.89 +	lb2 = lb1;
    1.90 +
    1.91 +	emitln("jz %s", labelstr(lb1));
    1.92 +	block();
    1.93 +
    1.94 +	if(look == 'l') {
    1.95 +		match('l');
    1.96 +		lb2 = newlabel();
    1.97 +		emitln("jmp %s", labelstr(lb2));
    1.98 +		postlabel(lb1);
    1.99 +		block();
   1.100 +	}
   1.101 +	match('e');
   1.102 +	postlabel(lb2);
   1.103 +}
   1.104 +
   1.105 +void dowhile(void)
   1.106 +{
   1.107 +	int lbtop, lbend;
   1.108 +
   1.109 +	match('w');
   1.110 +	lbtop = newlabel();
   1.111 +	lbend = newlabel();
   1.112 +	postlabel(lbtop);
   1.113 +	condition();
   1.114 +	emitln("jz %s", labelstr(lbend));
   1.115 +	block();
   1.116 +	match('e');
   1.117 +	emitln("jmp %s", labelstr(lbtop));
   1.118 +	postlabel(lbend);
   1.119 +}
   1.120 +
   1.121 +void condition(void)
   1.122 +{
   1.123 +	emitln("<condition>");
   1.124 +}
   1.125 +
   1.126  void expression(void)
   1.127  {
   1.128  	if(is_addsub(look)) {
   1.129 @@ -149,7 +233,7 @@
   1.130  	}
   1.131  }
   1.132  
   1.133 -void ident()
   1.134 +void ident(void)
   1.135  {
   1.136  	char name = get_name();
   1.137  	if(look == '(') {
   1.138 @@ -320,3 +404,21 @@
   1.139  	symlist = sym;
   1.140  	return 0;
   1.141  }
   1.142 +
   1.143 +int newlabel(void)
   1.144 +{
   1.145 +	static int n;
   1.146 +	return n++;
   1.147 +}
   1.148 +
   1.149 +const char *labelstr(int lb)
   1.150 +{
   1.151 +	static char buf[16];
   1.152 +	sprintf(buf, "L%02d", lb);
   1.153 +	return buf;
   1.154 +}
   1.155 +
   1.156 +void postlabel(int lb)
   1.157 +{
   1.158 +	fprintf(outfile, "%s:\n", labelstr(lb));
   1.159 +}