Create separate extetnd.c file for handling extensions / %extend

This is just a simple code refactor, moving and function renaming to
remove the %extend code out of the parser into its own file now
 that it isn't just used in the parser.

Source/Swig/extend.c

@@ -0,0 +1,141 @@
+/* -----------------------------------------------------------------------------
+ * This file is part of SWIG, which is licensed as a whole under version 3 
+ * (or any later version) of the GNU General Public License. Some additional
+ * terms also apply to certain portions of SWIG. The full details of the SWIG
+ * license and copyrights can be found in the LICENSE and COPYRIGHT files
+ * included with the SWIG source code as distributed by the SWIG developers
+ * and at http://www.swig.org/legal.html.
+ *
+ * extend.c
+ *
+ * Extensions support (%extend)
+ * ----------------------------------------------------------------------------- */
+
+#include "swig.h"
+#include "cparse.h"
+
+static Hash *extendhash = 0;     /* Hash table of added methods */
+
+/* -----------------------------------------------------------------------------
+ * Swig_extend_hash()
+ *
+ * Access the extend hash
+ * ----------------------------------------------------------------------------- */
+Hash *Swig_extend_hash(void) {
+  if (!extendhash)
+    extendhash = NewHash();
+  return extendhash;
+}
+
+/* -----------------------------------------------------------------------------
+ * Swig_extend_merge()
+ *
+ * Extension merge.  This function is used to handle the %extend directive
+ * when it appears before a class definition.   To handle this, the %extend
+ * actually needs to take precedence.  Therefore, we will selectively nuke symbols
+ * from the current symbol table, replacing them with the added methods.
+ * ----------------------------------------------------------------------------- */
+
+void Swig_extend_merge(Node *cls, Node *am) {
+  Node *n;
+  Node *csym;
+
+  n = firstChild(am);
+  while (n) {
+    String *symname;
+    if (Strcmp(nodeType(n),"constructor") == 0) {
+      symname = Getattr(n,"sym:name");
+      if (symname) {
+	if (Strcmp(symname,Getattr(n,"name")) == 0) {
+	  /* If the name and the sym:name of a constructor are the same,
+             then it hasn't been renamed.  However---the name of the class
+             itself might have been renamed so we need to do a consistency
+             check here */
+	  if (Getattr(cls,"sym:name")) {
+	    Setattr(n,"sym:name", Getattr(cls,"sym:name"));
+	  }
+	}
+      } 
+    }
+
+    symname = Getattr(n,"sym:name");
+    DohIncref(symname);
+    if ((symname) && (!Getattr(n,"error"))) {
+      /* Remove node from its symbol table */
+      Swig_symbol_remove(n);
+      csym = Swig_symbol_add(symname,n);
+      if (csym != n) {
+	/* Conflict with previous definition.  Nuke previous definition */
+	String *e = NewStringEmpty();
+	String *en = NewStringEmpty();
+	String *ec = NewStringEmpty();
+	Printf(ec,"Identifier '%s' redefined by %%extend (ignored),",symname);
+	Printf(en,"%%extend definition of '%s'.",symname);
+	SWIG_WARN_NODE_BEGIN(n);
+	Swig_warning(WARN_PARSE_REDEFINED,Getfile(csym),Getline(csym),"%s\n",ec);
+	Swig_warning(WARN_PARSE_REDEFINED,Getfile(n),Getline(n),"%s\n",en);
+	SWIG_WARN_NODE_END(n);
+	Printf(e,"%s:%d:%s\n%s:%d:%s\n",Getfile(csym),Getline(csym),ec, 
+	       Getfile(n),Getline(n),en);
+	Setattr(csym,"error",e);
+	Delete(e);
+	Delete(en);
+	Delete(ec);
+	Swig_symbol_remove(csym);              /* Remove class definition */
+	Swig_symbol_add(symname,n);            /* Insert extend definition */
+      }
+    }
+    n = nextSibling(n);
+  }
+}
+
+/* -----------------------------------------------------------------------------
+ * Swig_extend_append_previous()
+ * ----------------------------------------------------------------------------- */
+
+void Swig_extend_append_previous(Node *cls, Node *am) {
+  Node *n, *ne;
+  Node *pe = 0;
+  Node *ae = 0;
+
+  if (!am) return;
+  
+  n = firstChild(am);
+  while (n) {
+    ne = nextSibling(n);
+    set_nextSibling(n,0);
+    /* typemaps and fragments need to be prepended */
+    if (((Cmp(nodeType(n),"typemap") == 0) || (Cmp(nodeType(n),"fragment") == 0)))  {
+      if (!pe) pe = new_node("extend");
+      appendChild(pe, n);
+    } else {
+      if (!ae) ae = new_node("extend");
+      appendChild(ae, n);
+    }    
+    n = ne;
+  }
+  if (pe) prependChild(cls,pe);
+  if (ae) appendChild(cls,ae);
+}
+ 
+
+/* -----------------------------------------------------------------------------
+ * Swig_extend_unused_check()
+ *
+ * Check for unused %extend.  Special case, don't report unused
+ * extensions for templates
+ * ----------------------------------------------------------------------------- */
+ 
+void Swig_extend_unused_check(void) {
+  Iterator ki;
+
+  if (!extendhash) return;
+  for (ki = First(extendhash); ki.key; ki = Next(ki)) {
+    if (!Strchr(ki.key,'<')) {
+      SWIG_WARN_NODE_BEGIN(ki.item);
+      Swig_warning(WARN_PARSE_EXTEND_UNDEF,Getfile(ki.item), Getline(ki.item), "%%extend defined for an undeclared class %s.\n", SwigType_namestr(ki.key));
+      SWIG_WARN_NODE_END(ki.item);
+    }
+  }
+}
+

Source/Swig/swig.h

@@ -420,6 +420,13 @@ extern int        ParmList_is_compactdefargs(ParmList *p);
   extern void Swig_fragment_emit(String *name);
   extern void Swig_fragment_clear(String *section);
 
+/* --- Extension support --- */
+
+  extern Hash *Swig_extend_hash(void);
+  extern void Swig_extend_merge(Node *cls, Node *am);
+  extern void Swig_extend_append_previous(Node *cls, Node *am);
+  extern void Swig_extend_unused_check(void);
+
 /* hacks defined in C++ ! */
   extern int Swig_director_mode(void);
   extern int Swig_director_protected_mode(void);