Clean up the parser.

3 files changed, 100 insertions, 142 deletions

diff --git a/LuaSL/src/LuaSL_LSL_tree.c b/LuaSL/src/LuaSL_LSL_tree.c
index 78da8e7..7ea5d67 100644
--- a/LuaSL/src/LuaSL_LSL_tree.c
+++ b/LuaSL/src/LuaSL_LSL_tree.c
@@ -1,63 +1,85 @@
 /*
  * Implementation of functions used to build the abstract syntax tree.
  */
- 
-#include "LuaSL_LSL_tree.h"
+
+#include "LuaSL_parser_param.h"
+#include "LuaSL_yaccer.tab.h"
 #include <stdlib.h>
- 
+
 /**
  * @brief Allocates space for expression
  * @return The expression or NULL if not enough memory
  */
-static SExpression* allocateExpression()
+static SExpression* newExpression(EOperationType type, SExpression *left, SExpression *right, int value)
 {
-        SExpression* b = malloc(sizeof *b);
- 
-        if( b == NULL ) return NULL;
- 
-        b->type = eVALUE;
-        b->value = 0;
- 
-        b->left = NULL;
-        b->right = NULL;
- 
-        return b;
+    SExpression* b = malloc(sizeof *b);
+
+    if (b == NULL) return NULL;
+
+    b->type = type;
+    b->value = value;
+    b->left = left;
+    b->right = right;
+
+    return b;
 }
- 
+
 SExpression* createNumber(int value)
 {
-        SExpression* b = allocateExpression();
- 
-        if( b == NULL ) return NULL;
- 
-        b->type = eVALUE;
-        b->value = value;
- 
-        return b;
+    return newExpression(eVALUE, NULL, NULL, value);
 }
- 
-SExpression *createOperation( 
-                        EOperationType type,
-                        SExpression *left,
-                        SExpression *right)
+
+SExpression *createOperation(EOperationType type, SExpression *left, SExpression *right)
 {
-        SExpression* b = allocateExpression();
- 
-        if( b == NULL ) return NULL;
- 
-        b->type = type;
-        b->left = left;
-        b->right = right;
- 
-        return b;
+    return newExpression(type, left, right, 0);
 }
- 
+
+int evaluate(SExpression *e)
+{
+    switch(e->type)
+    {
+        case eVALUE:
+            return e->value;
+        case eMULTIPLY:
+            return evaluate(e->left) * evaluate(e->right);
+        case ePLUS:
+            return evaluate(e->left) + evaluate(e->right);
+        default:
+            // shouldn't be here
+            return 0;
+    }
+}
+
 void deleteExpression(SExpression *b)
 {
-        if (b == NULL) return;
- 
-        deleteExpression(b->left);
-        deleteExpression(b->right);
- 
-        free(b);
+    if (b == NULL) return;
+
+    deleteExpression(b->left);
+    deleteExpression(b->right);
+
+    free(b);
+}
+
+SExpression *getAST(const char *expr)
+{
+    SParserParam p;
+    YY_BUFFER_STATE state;
+
+    p.expression = NULL;
+    if (yylex_init(&(p.scanner)))
+        return NULL;
+
+    state = yy_scan_string(expr, p.scanner);
+    if (yyparse(&p))
+        return NULL;
+
+    yy_delete_buffer(state, p.scanner);
+    yylex_destroy(p.scanner);
+    return p.expression;
+}
+
+int yyerror(const char *msg)
+{
+    fprintf(stderr,"Error:%s\n",msg); return 0;
 }
+
diff --git a/LuaSL/src/LuaSL_LSL_tree.h b/LuaSL/src/LuaSL_LSL_tree.h
index 6d89672..71d372e 100644
--- a/LuaSL/src/LuaSL_LSL_tree.h
+++ b/LuaSL/src/LuaSL_LSL_tree.h
@@ -3,7 +3,7 @@
  */
 #ifndef __EXPRESSION_H__
 #define __EXPRESSION_H__
- 
+
 /**
  * @brief The operation type
  */
@@ -12,27 +12,27 @@ typedef enum tagEOperationType
     eVALUE,
     eMULTIPLY,
     ePLUS
-}EOperationType;
- 
+} EOperationType;
+
 /**
  * @brief The expression structure
  */
 typedef struct tagSExpression
 {
-        EOperationType type;///< type of operation
- 
-        int value;///< valid only when type is eVALUE
-        struct tagSExpression* left; ///< left side of the tree
-        struct tagSExpression* right;///< right side of the tree
-}SExpression;
- 
+    EOperationType type;///< type of operation
+
+    int value;///< valid only when type is eVALUE
+    struct tagSExpression* left; ///< left side of the tree
+    struct tagSExpression* right;///< right side of the tree
+} SExpression;
+
 /**
  * @brief It creates an identifier
  * @param value The number value
  * @return The expression or NULL in case of no memory
  */
 SExpression* createNumber(int value);
- 
+
 /**
  * @brief It creates an operation
  * @param type The operation type
@@ -40,16 +40,20 @@ SExpression* createNumber(int value);
  * @param right The right operand
  * @return The expression or NULL in case of no memory
  */
-SExpression* createOperation(
-                        EOperationType type,
-                        SExpression *left,
-                        SExpression *right);
- 
+SExpression* createOperation(EOperationType type, SExpression *left, SExpression *right);
+
 /**
  * @brief Deletes a expression
  * @param b The expression
  */
 void deleteExpression(SExpression *b);
- 
+
+SExpression *getAST(const char *expr);
+
+int evaluate(SExpression *e);
+
+int yyerror(const char *msg);
+int yyparse(void *param);
+
 #endif // __EXPRESSION_H__
 
diff --git a/LuaSL/src/LuaSL_parser.c b/LuaSL/src/LuaSL_parser.c
index 9e1d3ca..c6026e2 100644
--- a/LuaSL/src/LuaSL_parser.c
+++ b/LuaSL/src/LuaSL_parser.c
@@ -1,86 +1,18 @@
-#include "LuaSL_parser_param.h"
-#include "LuaSL_yaccer.tab.h"
- 
- 
-int yyparse(void *param);
- 
-static int initParserParam(SParserParam* param)
-{
-        int ret = 0;
- 
-        ret = yylex_init(&param->scanner);
-        param->expression = NULL;
- 
-        return ret;
-}
- 
-static int destroyParserParam(SParserParam* param)
-{
-        return yylex_destroy(param->scanner);
-}
- 
-SExpression *getAST(const char *expr)
-{
-        SParserParam p;
-        YY_BUFFER_STATE state;
- 
-        if ( initParserParam(&p) )
-        {
-                // couldn't initialize
-                return NULL;
-        }
- 
-        state = yy_scan_string(expr, p.scanner);
- 
-        if ( yyparse(&p) )
-        {
-                // error parsing
-                return NULL;
-        }
- 
-        yy_delete_buffer(state, p.scanner);
- 
-        destroyParserParam(&p);
- 
-        return p.expression;
-}
- 
-int evaluate(SExpression *e)
-{
-        switch(e->type)
-        {
-                case eVALUE:
-                        return e->value;
-                case eMULTIPLY:
-                        return evaluate(e->left) * evaluate(e->right);
-                case ePLUS:
-                        return evaluate(e->left) + evaluate(e->right);
-                default:
-                        // shouldn't be here
-                        return 0;
-        }
-}
+#include "LuaSL_LSL_tree.h"
+#include <stdio.h>
 
-int yyerror(const char *msg)
-{
-        fprintf(stderr,"Error:%s\n",msg); return 0;
-}
 
 int main(void)
 {
-        SExpression *e = NULL;
-        char test[]=" 4 + 2*10 + 3*( 5 + 1 )";
-        int result = 0;
- 
-        e = getAST(test);
- 
-        result = evaluate(e);
- 
-        printf("Result of '%s' is %d\n", test, result);
- 
-        deleteExpression(e);
- 
-        return 0;
-}
+    char test[]=" 4 + 2*10 + 3*( 5 + 1 )";
+    SExpression *e = NULL;
+    int result = 0;
+
+    e = getAST(test);
+    result = evaluate(e);
+    printf("Result of '%s' is %d\n", test, result);
+    deleteExpression(e);
 
+    return 0;
+}