From fa9f360626f91ca9fd6945aace8c90c9ec4bf077 Mon Sep 17 00:00:00 2001
From: Anicka Bernathova <anicka@anicka.net>
Date: Fri, 4 Jul 2008 20:42:19 +0200
Subject: [PATCH] parsing conditions

---
 cond.y | 217 +++++++++++++++++++++++++++++++++++++++++++++++++--------
 lex.c  |  10 +--
 2 files changed, 192 insertions(+), 35 deletions(-)

diff --git a/cond.y b/cond.y
index 6473557..34af263 100644
--- a/cond.y
+++ b/cond.y
@@ -4,64 +4,226 @@
 #include <string.h>
 #include <pcre.h>
 
+#include "lex.h"
+
 #define OVECCOUNT 3
 
 int yylex (void);
 void yyerror (char const *);
 
 int regex_cmp(char* s, char* r);
+struct tree* tree_malloc(int type);
+
+struct tree {
+	enum {
+		ST_IF,
+		ST_COND,
+		ST_BLOCK,
+		ST_ASS,
+		ST_LEAF,
+		ST_EMPTY
+	} st;
+	union {
+		struct {
+			struct tree* c;
+			struct tree* i;
+			struct tree* e; 
+		} tif;
+
+		struct {
+			int op;	
+			struct tree* left;
+			struct tree* right;
+		} cond;
+
+		struct {
+			struct tree* head;
+			struct tree* tail;
+		} block;
+
+		struct {
+			struct tree* left;
+			struct tree* right;
+		} ass;
+
+		struct {
+			enum {
+				L_VAR,
+				L_CONST,
+				L_NUM
+			} type;
+			union {
+				char* s;
+				int n;
+			} value;
+		} leaf;
+
+	} pt;
+};
 
 %}
 
 %union {
-	int b;	
 	int n;
 	char* str;
+	struct tree* tr;	
 }
 
 %token <str> CONST
 %token <n> NUM
 %token <str> VAR
-%token KW_IF KW_ELSE KW_PIPE KW_MAIL KW_COPY
-%token '(' ')' '{' '}'
+%token KW_PIPE KW_MAIL KW_COPY
+%token '(' ')' '{' '}' ';'
+%left KW_ELSE
+%left KW_IF
 %left ARROW
-%left EQ NEQ GE LE '<' '>' RE NRE
+%left <n> EQ NEQ GE LE '<' '>' RE NRE
 %left '+' '-' 
 %left '*' '/'
-%left '|' '&' '^'
-%left '!'
-%left '=' 
-%type <b> boo
+%left <n> '|'
+%left <n> '^'
+%left <n> '&'
+%left <n> '!'
+%left '='
+%type <tr> input 
+%type <tr> command 
+%type <tr> next 
+%type <tr> ass 
+%type <tr> ass_right 
+%type <tr> cif
+%type <tr> cond
+%type <n> rop 
 
 %%
-input:	/* empty */
-	| input line
+input:	/* empty */	{ $$ = NULL }
+	| command input { 	$$ = tree_malloc(ST_BLOCK); 
+				$$->pt.block.head = $1;
+				$$->pt.block.tail = $2; 
+			} 
+;
+
+command:	 ';' { $$ = tree_malloc(ST_EMPTY); }
+		| '{' command next '}' 	{
+						$$ = tree_malloc(ST_BLOCK); 
+						$$->pt.block.head = $2;
+						$$->pt.block.tail = $3; 
+					}
+		| '{' '}' { $$ = NULL }
+		| cif { $$ = $1 }
+		| ass ';' { $$ = $1}
+		
+ 	
+;
+
+next:	/* empty */ {$$ = NULL}
+	| command
+	
+
+;
+
+cif:	KW_IF cond command KW_ELSE command 	{ 
+					$$ = tree_malloc(ST_IF);
+					$$->pt.tif.c = $2;
+					$$->pt.tif.i = $3;
+					$$->pt.tif.e = $5;
+				}
+	| KW_IF cond command 	{ 
+					$$ = tree_malloc(ST_IF);
+					$$->pt.tif.c = $2;
+					$$->pt.tif.i = $3;
+					$$->pt.tif.e = NULL;
+				}
 ;
 
-line:	'\n'
-	| boo '\n'	 	{ printf("%s\n",$1?"true":"false"); }
-	| error '\n' 		{ yyerrok; }
+cond:	'!' cond {
+				$$ = tree_malloc(ST_COND);
+				$$->pt.cond.left = $2;	
+				$$->pt.cond.right = NULL;	
+				$$->pt.cond.op = $1;	
+
+		}
+	| cond '|' cond {
+				$$ = tree_malloc(ST_COND);
+				$$->pt.cond.left = $1;	
+				$$->pt.cond.right = $3;	
+				$$->pt.cond.op = $2;	
+
+			}
+	| cond '&' cond {
+				$$ = tree_malloc(ST_COND);
+				$$->pt.cond.left = $1;	
+				$$->pt.cond.right = $3;	
+				$$->pt.cond.op = $2;	
+
+			}
+	| cond '^' cond {
+				$$ = tree_malloc(ST_COND);
+				$$->pt.cond.left = $1;	
+				$$->pt.cond.right = $3;	
+				$$->pt.cond.op = $2;	
+
+			}
+	| '(' cond ')' { $$ = $2; }
+	| ass_right rop ass_right 	{
+						$$ = tree_malloc(ST_COND);
+						$$->pt.cond.left = $1;	
+						$$->pt.cond.right = $3;	
+						$$->pt.cond.op = $2;	
+					}
 ;
 
-boo:	 CONST EQ CONST 	{ $$ = ! strcmp($1, $3); }
-	| CONST NEQ CONST 	{ $$ = !! strcmp($1, $3); }
-	| CONST RE CONST	{ $$ = regex_cmp($1,$3) >= 0 }
-	| CONST NRE CONST	{ $$ = regex_cmp($1,$3) < 0 }
-	| NUM EQ NUM		{ $$ = $1 == $3 }
-	| NUM NEQ NUM		{ $$ = $1 != $3 }
-	| NUM GE NUM		{ $$ = $1 >= $3 }
-	| NUM LE NUM		{ $$ = $1 <= $3 }
-	| NUM '>' NUM		{ $$ = $1 > $3 }
-	| NUM '<' NUM		{ $$ = $1 < $3 }
-	| boo '|' boo 		{ $$ = $1 || $3 }
-	| boo '&' boo		{ $$ = $1 && $3 }
-	| boo '^' boo		{ $$ = ($1 || $3) && !($1 && $3) }
-	| '!' boo		{ $$ = ! $2 }
+rop:	'>'
+	| '<'
+	| EQ
+	| NEQ
+	| LE
+	| GE
+	| RE
+	| NRE
 ;
 
+ass:
+	VAR '=' ass_right	{
+					$$ = tree_malloc(ST_ASS);
+
+					$$->pt.ass.left = tree_malloc(ST_LEAF);
+					$$->pt.ass.left->pt.leaf.type = L_VAR;
+					$$->pt.ass.left->pt.leaf.value.s = $1;
+
+					$$->pt.ass.right = $3;
+				}
 ;
+
+ass_right:	NUM 	{ 
+				$$ = tree_malloc(ST_LEAF);
+				$$->pt.leaf.type = L_NUM;
+				$$->pt.leaf.value.n = $1;
+			}
+		| VAR 	{
+				$$ = tree_malloc(ST_LEAF);
+				$$->pt.leaf.type = L_VAR;
+				$$->pt.leaf.value.s = $1;
+			}
+		| CONST {
+				$$ = tree_malloc(ST_LEAF);
+				$$->pt.leaf.type = L_CONST;
+				$$->pt.leaf.value.s = $1;
+			}
+
+;
+
 %%
 
+struct tree* 
+tree_malloc(int type)
+{
+	struct tree* temp;
+	temp = xmalloc(sizeof (struct tree));
+	temp->st=type;
+
+	return temp;
+}
+
 int 
 regex_cmp(char* s, char* r)
 {
@@ -75,7 +237,6 @@ regex_cmp(char* s, char* r)
 		return -1;
 	
 	int res = pcre_exec(brum,NULL,s,strlen(s),0,0,ovector,OVECCOUNT);
-	
 	pcre_free(brum);
 
 	return res;
diff --git a/lex.c b/lex.c
index 4ee876d..ba892db 100644
--- a/lex.c
+++ b/lex.c
@@ -115,18 +115,13 @@ is_alpha(int c)
 int
 yylex(void)
 {
-	int c, nl = 0;
+	int c;
 	
 	while ((c = getchar ()) == ' ' || c == '\t' || c =='\n'){
-		if (c == '\n'){
-			nl = 1;
+		if (c == '\n')
 			line++;
-		}
 	}
 	
-	if (nl)
-		return '\n';
-	
 	if (c == EOF)
 		return 0;
 	
@@ -158,6 +153,7 @@ yylex(void)
 		case '<':
 		case '>':
 		case '=':
+		case ';':
 			return c;
 		
 		case '"':
-- 
2.39.5