1 files changed, 82 insertions, 0 deletions
diff --git a/maildrop/recipe.h b/maildrop/recipe.h
new file mode 100644
index 0000000..7b84c2c
--- /dev/null
+++ b/maildrop/recipe.h
@@ -0,0 +1,82 @@
+#ifndef recipe_h
+#define	recipe_h
+
+
+#include	"config.h"
+#include	"recipenode.h"
+#include	"token.h"
+
+class Lexer;
+class Token;
+
+//////////////////////////////////////////////////////////////////////////
+//
+// Class Recipe - parsed structure of a recipe file.
+// This class reads tokens from the Lexer class, and arranges them in a
+// logical structure that represents the recipe file.  The Recipe object
+// maints a list of RecipeNode objects, which roughly represent individual
+// statements, and elements of a recipe file.  There is more or less a
+// one-to-one relationship between Tokens and Recipenodes.  Usually one
+// RecipeNode is created for each token - but not always.  The RecipeNode
+// objects are automatically created by the Recipe object when ParseRecipe()
+// is called to translate the tokens returned by the Lexer class into
+// the RecipeNode structure.  When the Recipe object is destroyed, it
+// automatically destroys all RecipeNode objects it has allocated.
+// The RecipeNode objects are created using a simple recursive-descent
+// parser.
+//
+// The ExecuteRecipe() function actually starts the ball rolling by
+// calling the Evaluate() function of the first RecipeNode object in the
+// structure.
+//
+//////////////////////////////////////////////////////////////////////////
+
+
+#include	"../dbobj.h"
+
+class Recipe {
+
+	RecipeNode *firstNode, *lastNode;	// All nodes in this recipe.
+	RecipeNode *topNode;			// Topmost node.
+
+	RecipeNode *alloc(RecipeNode::RecipeNodeType);
+
+	Lexer	*lex;
+	Token	cur_tok;
+
+public:
+	Recipe();
+	~Recipe();
+
+	int ParseRecipe(Lexer &);
+	void ExecuteRecipe();
+	void errmsg(RecipeNode &, const char *);
+
+#ifdef	DbObj
+	DbObj	gdbm_file;
+#endif
+
+private:
+	// This is, essentially, a recursive-descent parser that builds
+	// the RecipeNode tree.
+	RecipeNode *ParseExpr()
+		{
+			return (ParseAssign());
+		}
+	RecipeNode *ParseAssign();
+	RecipeNode *ParseLogicalOr();
+	RecipeNode *ParseLogicalAnd();
+	RecipeNode *ParseComparison();
+	RecipeNode *ParseBitwiseOr();
+	RecipeNode *ParseBitwiseAnd();
+	RecipeNode *ParseAddSub();
+	RecipeNode *ParseMultDiv();
+	RecipeNode *ParseStrRegExp();
+	RecipeNode *ParseStatementList();
+	RecipeNode *ParseStatement();
+	RecipeNode *ParseSubStatement();
+	RecipeNode *ParseString();
+	RecipeNode *ParseElement();
+} ;
+
+#endif