Additions to %types so that a user can specify the code to go into the casting / conversion function

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@10222 626c5289-ae23-0410-ae9c-e8d60b6d4f22

CHANGES.current

@@ -1,6 +1,37 @@
 Version 1.3.34 (in progress)
 ============================
 
+01/31/2008: wsfulton
+            Additions to the %types directive. Now the conversion / casting code can be
+            overridden to some custom code in the %types directive, like so:
+
+              %types(fromtype = totype) %{
+                ... code to convert fromtype to totype and return ...
+              %}
+
+            The special variable $from will be replaced by the name of the parameter of the
+            type being converted from. The code must return the totype cast to void *. Example:
+
+              class Time;
+              class Date;
+              Date &Time::dateFromTime();
+
+              %types(Time = Date) %{
+                Time *t = (Time *)$from;
+                Date &d = t->dateFromTime();
+                return (void *) &d;
+              %}
+
+            resulting in the conversion / casting code looking something like:
+
+              static void *_p_TimeTo_p_Date(void *x) {
+                Time *t = (Time *)x;
+                Date &d = t->dateFromTime();
+                return (void *) &d;
+              }
+
+            This is advanced usage, please use only if you understand the runtime type system.
+
 01/30/2008: mgossage
 	    Small update to documentation in Typemaps.html, to warn about use of local 
 	    variables in typemaps for multiple types.
@@ -26,7 +57,7 @@ Version 1.3.34 (in progress)
             containers should be faster.
 
 01/18/2008: wsfulton
-	    Add 'directorinattributes' and 'directoroutattributes' typemap attributes
+	    [C#] Add 'directorinattributes' and 'directoroutattributes' typemap attributes
             for the imtype typemap. These should contain C# attributes which will
             be generated into the C# director delegate methods.
 

Source/CParse/parser.y

@@ -1804,10 +1804,6 @@ except_directive : EXCEPT LPAREN ID RPAREN LBRACE {
 	       }
                ;
 
-/* ------------------------------------------------------------
-   %fragment(name,location) { ... }
-   ------------------------------------------------------------ */
-
 /* fragment keyword arguments */
 stringtype    : string LBRACE parm RBRACE {		 
                  $$ = NewHash();
@@ -1825,6 +1821,14 @@ fname         : string {
               }
               ;
 
+/* ------------------------------------------------------------
+   %fragment(name, section) %{ ... %}
+   %fragment("name" {type}, "section") %{ ... %}
+   %fragment("name", "section", fragment="fragment1", fragment="fragment2") %{ ... %}
+   Also as above but using { ... }
+   %fragment("name");
+   ------------------------------------------------------------ */
+
 fragment_directive: FRAGMENT LPAREN fname COMMA kwargs RPAREN HBLOCK {
                    Hash *p = $5;
 		   $$ = new_node("fragment");
@@ -2502,11 +2506,14 @@ typemap_parm   : type typemap_parameter_declarator {
 
 /* ------------------------------------------------------------
    %types(parmlist); 
+   %types(parmlist) %{ ... %}
    ------------------------------------------------------------ */
 
-types_directive : TYPES LPAREN parms RPAREN SEMI {
+types_directive : TYPES LPAREN parms RPAREN stringbracesemi {
                    $$ = new_node("types");
 		   Setattr($$,"parms",$3);
+                   if ($5)
+		     Setattr($$,"convcode",NewString($5));
                }
                ;
 

Source/Modules/lang.cxx

@@ -776,6 +776,7 @@ int Language::typemapcopyDirective(Node *n) {
 
 int Language::typesDirective(Node *n) {
   Parm *parms = Getattr(n, "parms");
+  String *convcode = Getattr(n, "convcode"); /* optional user supplied conversion code for custom casting */
   while (parms) {
     SwigType *t = Getattr(parms, "type");
     String *v = Getattr(parms, "value");
@@ -783,7 +784,7 @@ int Language::typesDirective(Node *n) {
       SwigType_remember(t);
     } else {
       if (SwigType_issimple(t)) {
-	SwigType_inherit(t, v, 0);
+	SwigType_inherit(t, v, 0, convcode);
       }
     }
     parms = nextSibling(parms);

Source/Modules/typepass.cxx

@@ -205,7 +205,7 @@ class TypePass:private Dispatcher {
 		Setmeta(bname, "already_warned", "1");
 	      }
 	    }
-	    SwigType_inherit(clsname, bname, cast);
+	    SwigType_inherit(clsname, bname, cast, 0);
 	  }
 	}
       }
@@ -225,7 +225,7 @@ class TypePass:private Dispatcher {
       String *bname = Getattr(n, "name");
       Node *bclass = n;		/* Getattr(n,"class"); */
       Hash *scopes = Getattr(bclass, "typescope");
-      SwigType_inherit(clsname, bname, cast);
+      SwigType_inherit(clsname, bname, cast, 0);
       if (!importmode) {
 	String *btype = Copy(bname);
 	SwigType_add_pointer(btype);

Source/Swig/typesys.c

@@ -1649,12 +1649,18 @@ String *SwigType_clientdata_collect(String *ms) {
  * from them.
  *
  * subclass is a hash that maps base-classes to all of the classes derived from them.
+ *
+ * derived - name of derived class
+ * base - name of base class
+ * cast - additional casting code when casting from derived to base
+ * conversioncode - if set, overrides the default code in the function when casting
+ *                from derived to base
  * ----------------------------------------------------------------------------- */
 
 static Hash *subclass = 0;
 static Hash *conversions = 0;
 
-void SwigType_inherit(String *derived, String *base, String *cast) {
+void SwigType_inherit(String *derived, String *base, String *cast, String *conversioncode) {
   Hash *h;
   String *dd = 0;
   String *bb = 0;
@@ -1685,7 +1691,13 @@ void SwigType_inherit(String *derived, String *base, String *cast) {
     Delete(h);
   }
   if (!Getattr(h, derived)) {
-    Setattr(h, derived, cast ? cast : (void *) "");
+    Hash *c = NewHash();
+    if (cast)
+      Setattr(c, "cast", cast);
+    if (conversioncode)
+      Setattr(c, "convcode", conversioncode);
+    Setattr(h, derived, c);
+    Delete(c);
   }
 
   Delete(dd);
@@ -1781,8 +1793,20 @@ void SwigType_inherit_equiv(File *out) {
 	String *convname = NewStringf("%sTo%s", mprefix, mkey);
 	String *lkey = SwigType_lstr(rk.key, 0);
 	String *lprefix = SwigType_lstr(prefix, 0);
-	Printf(out, "static void *%s(void *x) {\n", convname);
-	Printf(out, "    return (void *)((%s) %s ((%s) x));\n", lkey, Getattr(sub, bk.key), lprefix);
+        Hash *subhash = Getattr(sub, bk.key);
+        String *convcode = Getattr(subhash, "convcode");
+	Printf(out, "static void *%s(void *x) {", convname);
+        if (convcode) {
+          String *fn = Copy(convcode);
+          Replaceall(fn, "$from", "x");
+          Printf(out, "%s", fn);
+        } else {
+          String *cast = Getattr(subhash, "cast");
+          Printf(out, "\n    return (void *)((%s) ", lkey);
+          if (cast)
+            Printf(out, "%s", cast);
+          Printf(out, " ((%s) x));\n", lprefix);
+        }
 	Printf(out, "}\n");
 	Setattr(conversions, ckey, convname);
 	Delete(ckey);