Beginnings of an implementation of a type object

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@156 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Source/Swig/Makefile.in

@@ -16,7 +16,7 @@
 #
 #----------------------------------------------------------------
 
-SRCS          = types.c scanner.c include.c getopt.c misc.c super.c
+SRCS          = types.c scanner.c include.c getopt.c misc.c super.c type.c
 OBJS          = $(SRCS:.c=.o)
 INTERFACE     = swig.i
 WRAPFILE      = $(INTERFACE:.i=_wrap.c)

Source/Swig/type.c

@@ -0,0 +1,163 @@
+/* ------------------------------------------------------------------------- 
+ * type.c
+ *
+ *     Definition of a DOH type to represent a C type.  The interface
+ *     to this DOH type is fairly simple, but its implementation is
+ *     complex, as it uses a tree structure internally to cache
+ *     already-represented types and avoid the need to allocate an
+ *     entire DOH object every time a type object is created.
+ * 
+ * Author(s) : Dustin Mitchell (djmitche@cs.uchicago.edu)
+ *
+ * Copyright (C) 1999-2000.  The University of Chicago
+ * See the file LICENSE for information on usage and redistribution.	
+ * ------------------------------------------------------------------------- */
+
+#include "doh.h"
+#include "swig.h"
+
+static char cvstag[] = "$Header$";
+
+/* =========================================================================
+ * implementation overview
+ * ========================================================================= */
+
+/* Public appearance
+
+   To the public, types appear as a chain of constructors, e.g.
+
+   t = Pointer(Pointer(Array(Pointer(Char()))))
+
+   where each of the constructors can have some attributes (const /
+   volatile, array size, etc.)
+
+   The 'parent' of a type is the argument to the outermost constructor
+   used in the creation of that type.  Thus the parent of t is
+
+   tp = Pointer(Array(Pointer(Char())))
+
+
+   Internal representation
+
+   In order to save space, we store all of our types in a large tree.
+   Because types are constructed from the innermost constructor out
+   (e.g. 'Char()' would be the first call in the example above), we
+   put the base types (e.g. Char, Int, UInt) at the base of this tree,
+   and build from there.  Thus we would find 't', above, by beginning
+   at the root of the tree and following the path Char, Pointer,
+   Array, Pointer, Pointer.  If we were to construct a type
+
+   t2 = Array(Pointer(Char()))
+
+   we would first walk from our root via the path Char, Pointer,
+   Array, and then return a pointer to that node.  To construct
+
+   t3 = Pointer(Pointer(Char()))
+
+   we would walk from our root via the path Char, Pointer, Pointer,
+   where we create the final node.
+
+   Fortunately, when we refer to the 'parent' of a type, it is also
+   that type's parent in our tree.  Similarly, the 'children' of a
+   given type are not visible to the user, but are all the types
+   defined by application of further constructors to the given
+   type. */
+
+
+/* =========================================================================
+ * constants for internal use
+ * ========================================================================= */
+
+/* Base types
+
+   Base types have no parent (with one exception; see *), and can be
+   const or volatile.  Width specifies the length in bits of an
+   integral type, and the length in bits of the mantissa of a Float.
+   Exp_width specifies the width of the exponent in a float type.
+   Name specifies the name of a Name type, as well as the optional tag
+   for an Enum or Struct.  Attributes specifies the indirect
+   attributes of a type.  For Enums, this is the optional list of
+   defined names and their values.  For Structs, this is an optional
+   list of the types and names of the members.
+
+   (*) If a Name's underlying type is known, then its child field
+   points to that type. */
+   
+#define Swig_Type_Int 1
+#define Swig_Type_UInt 2
+#define Swig_Type_Float 3
+#define Swig_Type_Void 4
+#define Swig_Type_Char 5
+#define Swig_Type_Name 6
+#define Swig_Type_Enum 7
+#define Swig_Type_Struct 8
+
+/* Constructors
+
+   Constructors have a parent.  Further, Arrays may have their size
+   expression in 'attributes', and Functions have the types and names
+   of their arguments in 'attributes'.  A Pointer may be const or
+   volatile (which characteristic more accurately applies to its
+   child, although this is a matter of interpretation). */
+
+#define Swig_Type_Array 11
+#define Swig_Type_Function 12
+#define Swig_Type_Pointer 13
+
+/* Subtypes 
+
+   A Struct may either be a Struct or a Union -- since SWIG handles
+   them similarly, this is considered a subtype. */
+
+#define Swig_Subtype_Struct 81
+#define Swig_Subtype_Union 82
+
+/* =========================================================================
+ * structure definitions
+ * ========================================================================= */
+
+typedef struct Swig_Type_tag
+{
+   short type, subtype;
+   DOH *name, *attributes;
+} Swig_Type_tag;
+
+typedef DOH *Swig_Type_children;
+
+typedef struct Swig_Type_node
+{
+   Swig_Type_tag type;
+   struct Swig_Type_node *parent;
+   Swig_Type_hash children;
+} Swig_Type_node;
+
+/* =========================================================================
+ * static variables
+ * ========================================================================= */
+
+/* shorthand */
+#define ROOT Swig_Type_root
+static Swig_Type_children Swig_Type_root;
+
+/* =========================================================================
+ * utility function prototypes
+ * ========================================================================= */
+
+/* Take one step down into the children, creating a new node if
+   necessary. */
+static Swig_Type_node *
+Swig_Type_step(Swig_Type_hash children, Swig_Type_tag *tag);
+
+/* Functions to support hashing on Swig_Type_tag objects */
+
+/* =========================================================================
+ * utility functions
+ * ========================================================================= */
+
+/* -------------------------------------------------------------------------
+ * static Swig_Type_node *
+ * Swig_Type_step(Swig_Type_hash children, Swig_Type_tag *tag);
+ * -------------------------------------------------------------------------
+ * Take a step down the tree, creating a new node if necessary, and
+ * return a pointer to the node we arrive at.
+ * -------------------------------------------------------------------------