/trunk/Source/Modules/go.cxx

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/* -----------------------------------------------------------------------------
 * See the LICENSE file for information on copyright, usage and redistribution
 * of SWIG, and the README file for authors - http://www.swig.org/release.html.
 *
 * go.cxx
 *
 * Go language module for SWIG.
 * ----------------------------------------------------------------------------- */

char cvsroot_go_cxx[] = "$Id";

#include "swigmod.h"
#include "cparse.h"
#include <ctype.h>

#ifdef HAVE_GCCGO_46
 #define GCCGO_46_DEFAULT true
#else
 #define GCCGO_46_DEFAULT false
#endif

class GO:public Language {
  static const char *const usage;

  // Go package name.
  String *package;
  // Flag for generating gccgo output.
  bool gccgo_flag;
  // Flag for generating gccgo 4.6 output.
  bool gccgo_46_flag;
  // Prefix to use with gccgo.
  String *go_prefix;
  // Name of shared library to import.
  String *soname;
  // Size in bits of the C type "long".
  int long_type_size;

  /* Output files */
  File *f_c_begin;
  File *f_go_begin;
  File *f_gc_begin;

  /* Output fragments */
  File *f_c_runtime;
  File *f_c_header;
  File *f_c_wrappers;
  File *f_c_init;
  File *f_c_directors;
  File *f_c_directors_h;
  File *f_go_runtime;
  File *f_go_header;
  File *f_go_wrappers;
  File *f_gc_runtime;
  File *f_gc_header;
  File *f_gc_wrappers;

  // True if we imported a module.
  bool saw_import;
  // If not NULL, name of import package being processed.
  String *imported_package;
  // Build interface methods while handling a class.  This is only
  // non-NULL when we are handling methods.
  String *interfaces;
  // The class node while handling a class.  This is only non-NULL
  // when we are handling methods.
  Node *class_node;
  // The class name while handling a class.  This is only non-NULL
  // when we are handling methods.  This is the name of the class as
  // SWIG sees it.
  String *class_name;
  // The receiver name while handling a class.  This is only non-NULL
  // when we are handling methods.  This is the name of the class
  // as run through goCPointerType.
  String *class_receiver;
  // A hash table of method names that we have seen when processing a
  // class.  This lets us detect base class methods that we don't want
  // to use.
  Hash *class_methods;
  // True when we are generating the wrapper functions for a variable.
  bool making_variable_wrappers;
  // True when working with a static member function.
  bool is_static_member_function;
  // A hash table of types that we have seen but which may not have
  // been defined.  The index is a SwigType.
  Hash *undefined_types;
  // A hash table of classes which were defined.  The index is a Go
  // type name.
  Hash *defined_types;

public:
  GO():package(NULL),
     gccgo_flag(false),
     gccgo_46_flag(GCCGO_46_DEFAULT),
     go_prefix(NULL),
     soname(NULL),
     long_type_size(32),
     f_c_begin(NULL),
     f_go_begin(NULL),
     f_gc_begin(NULL),
     f_c_runtime(NULL),
     f_c_header(NULL),
     f_c_wrappers(NULL),
     f_c_init(NULL),
     f_c_directors(NULL),
     f_c_directors_h(NULL),
     f_go_runtime(NULL),
     f_go_header(NULL),
     f_go_wrappers(NULL),
     f_gc_runtime(NULL),
     f_gc_header(NULL),
     f_gc_wrappers(NULL),
     saw_import(false),
     imported_package(NULL),
     interfaces(NULL),
     class_node(NULL),
     class_name(NULL),
     class_receiver(NULL),
     class_methods(NULL),
     making_variable_wrappers(false),
     is_static_member_function(false),
     undefined_types(NULL),
     defined_types(NULL) {
    director_multiple_inheritance = 1;
    director_language = 1;
    director_prot_ctor_code = NewString("_swig_gopanic(\"accessing abstract class or protected constructor\");");
  }

private:
  /* ------------------------------------------------------------
   * main()
   * ------------------------------------------------------------ */
  virtual void main(int argc, char *argv[]) {

    SWIG_library_directory("go");

    // Process command line options.
    for (int i = 1; i < argc; i++) {
      if (argv[i]) {
	if (strcmp(argv[i], "-package") == 0) {
	  if (argv[i + 1]) {
	    package = NewString(argv[i + 1]);
	    Swig_mark_arg(i);
	    Swig_mark_arg(i + 1);
	    i++;
	  } else {
	    Swig_arg_error();
	  }
	} else if (strcmp(argv[i], "-gccgo") == 0) {
	  Swig_mark_arg(i);
	  gccgo_flag = true;
	} else if (strcmp(argv[i], "-gccgo-46") == 0) {
	  Swig_mark_arg(i);
	  gccgo_46_flag = true;
	} else if (strcmp(argv[i], "-no-gccgo-46") == 0) {
	  Swig_mark_arg(i);
	  gccgo_46_flag = false;
	} else if (strcmp(argv[i], "-go-prefix") == 0) {
	  if (argv[i + 1]) {
	    go_prefix = NewString(argv[i + 1]);
	    Swig_mark_arg(i);
	    Swig_mark_arg(i + 1);
	    i++;
	  } else {
	    Swig_arg_error();
	  }
	} else if (strcmp(argv[i], "-soname") == 0) {
	  if (argv[i + 1]) {
	    soname = NewString(argv[i + 1]);
	    Swig_mark_arg(i);
	    Swig_mark_arg(i + 1);
	    i++;
	  } else {
	    Swig_arg_error();
	  }
	} else if (strcmp(argv[i], "-longsize") == 0) {
	  if (argv[i + 1]) {
	    long_type_size = atoi(argv[i + 1]);
	    if (long_type_size != 32 && long_type_size != 64) {
	      Printf(stderr, "-longsize not 32 or 64\n");
	      Swig_arg_error();
	    }
	    Swig_mark_arg(i);
	    Swig_mark_arg(i + 1);
	    ++i;
	  } else {
	    Swig_arg_error();
	  }
	} else if (strcmp(argv[i], "-help") == 0) {
	  Printf(stdout, "%s\n", usage);
	}
      }
    }

    if (gccgo_flag && !go_prefix) {
      go_prefix = NewString("go");
    }

    // Add preprocessor symbol to parser.
    Preprocessor_define("SWIGGO 1", 0);

    if (gccgo_flag) {
      Preprocessor_define("SWIGGO_GCCGO 1", 0);
    }

    if (long_type_size == 32) {
      Preprocessor_define("SWIGGO_LONG_TYPE_SIZE 32", 0);
    } else {
      Preprocessor_define("SWIGGO_LONG_TYPE_SIZE 64", 0);
    }

    // Add typemap definitions.
    SWIG_typemap_lang("go");
    SWIG_config_file("go.swg");

    allow_overloading();
  }

  /* ---------------------------------------------------------------------
   * top()
   *
   * For 6g/8g, we are going to create the following files:
   *
   * 1) A .c or .cxx file compiled with gcc.  This file will contain
   *    function wrappers.  Each wrapper will take a pointer to a
   *    struct holding the arguments, unpack them, and call the real
   *    function.
   *
   * 2) A .go file which defines the Go form of all types, and which
   *    defines Go function wrappers.  Each wrapper will call the C
   *    function wrapper in the second file.
   *
   * 3) A .c file compiled with 6c/8c.  This file will define
   *    Go-callable C function wrappers.  Each wrapper will use
   *    cgocall to call the function wrappers in the first file.
   *
   * When generating code for gccgo, we don't need the third file, and
   * the function wrappers in the first file have a different form.
   *
   * --------------------------------------------------------------------- */

  virtual int top(Node *n) {
    Node *optionsnode = Getattr(Getattr(n, "module"), "options");
    if (optionsnode) {
      if (Getattr(optionsnode, "directors")) {
	allow_directors();
      }
      if (Getattr(optionsnode, "dirprot")) {
	allow_dirprot();
      }
      allow_allprotected(GetFlag(optionsnode, "allprotected"));
    }

    String *module = Getattr(n, "name");
    if (!package) {
      package = Copy(module);
    }
    if (!soname) {
      soname = Copy(package);
      Append(soname, ".so");
    }

    // Get filenames.

    String *c_filename = Getattr(n, "outfile");
    String *c_filename_h = Getattr(n, "outfile_h");

    String *go_filename = NewString("");
    Printf(go_filename, "%s%s.go", SWIG_output_directory(), module);

    String *gc_filename = NULL;
    if (!gccgo_flag) {
      gc_filename = NewString("");
      Printf(gc_filename, "%s%s_gc.c", SWIG_output_directory(), module);
    }

    // Open files.

    f_c_begin = NewFile(c_filename, "w", SWIG_output_files());
    if (!f_c_begin) {
      FileErrorDisplay(c_filename);
      SWIG_exit(EXIT_FAILURE);
    }

    if (directorsEnabled()) {
      if (!c_filename_h) {
	Printf(stderr, "Unable to determine outfile_h\n");
	SWIG_exit(EXIT_FAILURE);
      }
      f_c_directors_h = NewFile(c_filename_h, "w", SWIG_output_files());
      if (!f_c_directors_h) {
	FileErrorDisplay(c_filename_h);
	SWIG_exit(EXIT_FAILURE);
      }
    }

    f_go_begin = NewFile(go_filename, "w", SWIG_output_files());
    if (!f_go_begin) {
      FileErrorDisplay(go_filename);
      SWIG_exit(EXIT_FAILURE);
    }

    if (!gccgo_flag) {
      f_gc_begin = NewFile(gc_filename, "w", SWIG_output_files());
      if (!f_gc_begin) {
	FileErrorDisplay(gc_filename);
	SWIG_exit(EXIT_FAILURE);
      }
    }

    f_c_runtime = NewString("");
    f_c_header = NewString("");
    f_c_wrappers = NewString("");
    f_c_init = NewString("");
    f_c_directors = NewString("");
    f_go_runtime = NewString("");
    f_go_header = NewString("");
    f_go_wrappers = NewString("");
    if (!gccgo_flag) {
      f_gc_runtime = NewString("");
      f_gc_header = NewString("");
      f_gc_wrappers = NewString("");
    }

    Swig_register_filebyname("begin", f_c_begin);
    Swig_register_filebyname("runtime", f_c_runtime);
    Swig_register_filebyname("header", f_c_header);
    Swig_register_filebyname("wrapper", f_c_wrappers);
    Swig_register_filebyname("init", f_c_init);
    Swig_register_filebyname("director", f_c_directors);
    Swig_register_filebyname("director_h", f_c_directors_h);
    Swig_register_filebyname("go_begin", f_go_begin);
    Swig_register_filebyname("go_runtime", f_go_runtime);
    Swig_register_filebyname("go_header", f_go_header);
    Swig_register_filebyname("go_wrapper", f_go_wrappers);
    if (!gccgo_flag) {
      Swig_register_filebyname("gc_begin", f_gc_begin);
      Swig_register_filebyname("gc_runtime", f_gc_runtime);
      Swig_register_filebyname("gc_header", f_gc_header);
      Swig_register_filebyname("gc_wrapper", f_gc_wrappers);
    }

    Swig_banner(f_c_begin);

    if (directorsEnabled()) {
      Printf(f_c_runtime, "#define SWIG_DIRECTORS\n");

      Swig_banner(f_c_directors_h);
      Printf(f_c_directors_h, "#ifndef SWIG_%s_WRAP_H_\n", module);
      Printf(f_c_directors_h, "#define SWIG_%s_WRAP_H_\n\n", module);

      Printf(f_c_directors, "\n// C++ director class methods.\n");
      Printf(f_c_directors, "#include \"%s\"\n\n", Swig_file_filename(c_filename_h));
    }

    Swig_banner(f_go_begin);

    if (!gccgo_flag) {
      Swig_banner(f_gc_begin);
      Printf(f_gc_begin, "\n/* This file should be compiled with 6c/8c.  */\n");
      Printf(f_gc_begin, "#pragma dynimport _ _ \"%s\"\n", soname);
    }

    // Output module initialization code.

    Printf(f_go_begin, "\npackage %s\n\n", package);

    // All the C++ wrappers should be extern "C".

    Printv(f_c_wrappers, "#ifdef __cplusplus\n", "extern \"C\" {\n", "#endif\n\n", NULL);

    // Set up the hash table for types not defined by SWIG.

    undefined_types = NewHash();
    defined_types = NewHash();

    // Emit code.

    Language::top(n);

    // Write out definitions for the types not defined by SWIG.

    Printv(f_go_wrappers, "\n", NULL);
    for (Iterator p = First(undefined_types); p.key; p = Next(p)) {
      String *ty = goType(NULL, p.key);
      if (!Getattr(defined_types, ty)) {
	String *cp = goCPointerType(p.key, false);
	if (!Getattr(defined_types, cp)) {
	  Printv(f_go_wrappers, "type ", cp, " uintptr\n", NULL);
	  Printv(f_go_wrappers, "type ", ty, " interface {\n", NULL);
	  Printv(f_go_wrappers, "\tSwigcptr() uintptr;\n", NULL);
	  Printv(f_go_wrappers, "}\n", NULL);
	  Printv(f_go_wrappers, "func (p ", cp, ") Swigcptr() uintptr {\n", NULL);
	  Printv(f_go_wrappers, "\treturn uintptr(p)\n", NULL);
	  Printv(f_go_wrappers, "}\n\n", NULL);
	}
	Delete(cp);
      }
      Delete(ty);
    }
    Delete(undefined_types);
    Delete(defined_types);

    /* Write and cleanup */

    Dump(f_c_header, f_c_runtime);

    if (directorsEnabled()) {
      Printf(f_c_directors_h, "#endif\n");
      Close(f_c_directors_h);
      Delete(f_c_directors_h);
      f_c_directors_h = NULL;

      Dump(f_c_directors, f_c_runtime);
      Close(f_c_directors);
      Delete(f_c_directors);
      f_c_directors = NULL;
    }

    // End the extern "C".
    Printv(f_c_wrappers, "#ifdef __cplusplus\n", "}\n", "#endif\n\n", NULL);

    Dump(f_c_runtime, f_c_begin);
    Dump(f_c_wrappers, f_c_begin);
    Dump(f_c_init, f_c_begin);
    Dump(f_go_header, f_go_begin);
    Dump(f_go_runtime, f_go_begin);
    Dump(f_go_wrappers, f_go_begin);
    if (!gccgo_flag) {
      Dump(f_gc_header, f_gc_begin);
      Dump(f_gc_runtime, f_gc_begin);
      Dump(f_gc_wrappers, f_gc_begin);
    }

    Delete(f_c_runtime);
    Delete(f_c_header);
    Delete(f_c_wrappers);
    Delete(f_c_init);
    Delete(f_go_runtime);
    Delete(f_go_header);
    Delete(f_go_wrappers);
    if (!gccgo_flag) {
      Delete(f_gc_runtime);
      Delete(f_gc_header);
      Delete(f_gc_wrappers);
    }

    Close(f_c_begin);
    Delete(f_c_begin);
    Close(f_go_begin);
    Delete(f_go_begin);
    if (!gccgo_flag) {
      Close(f_gc_begin);
      Delete(f_gc_begin);
    }

    return SWIG_OK;
  }

  /* ------------------------------------------------------------
   * importDirective()
   *
   * Handle a SWIG import statement by generating a Go import
   * statement.
   * ------------------------------------------------------------ */

  virtual int importDirective(Node *n) {
    String *hold_import = imported_package;
    String *modname = Getattr(n, "module");
    if (modname) {
      Printv(f_go_begin, "import \"", modname, "\"\n", NULL);
      imported_package = modname;
      saw_import = true;
    }
    int r = Language::importDirective(n);
    imported_package = hold_import;
    return r;
  }

  /* ----------------------------------------------------------------------
   * functionWrapper()
   *
   * Implement a function.
   * ---------------------------------------------------------------------- */

  virtual int functionWrapper(Node *n) {
    if (GetFlag(n, "feature:ignore")) {
      return SWIG_OK;
    }

    // We don't need explicit calls.
    if (GetFlag(n, "explicitcall")) {
      return SWIG_OK;
    }

    String *name = Getattr(n, "sym:name");
    String *nodetype = Getattr(n, "nodeType");
    bool is_static = is_static_member_function || isStatic(n);
    bool is_friend = isFriend(n);
    bool is_ctor_dtor = false;

    SwigType *result = Getattr(n, "type");

    // For some reason SWIG changs the "type" value during the call to
    // functionWrapper.  We need to remember the type for possible
    // overload processing.
    Setattr(n, "go:type", Copy(result));

    String *go_name;

    String *r1 = NULL;
    if (making_variable_wrappers) {
      // Change the name of the variable setter and getter functions
      // to be more Go like.

      bool is_set = Strcmp(Char(name) + Len(name) - 4, "_set") == 0;
      assert(is_set || Strcmp(Char(name) + Len(name) - 4, "_get") == 0);

      // Start with Set or Get.
      go_name = NewString(is_set ? "Set" : "Get");

      // If this is a static variable, put in the class name,
      // capitalized.
      if (is_static && class_name) {
	String *ccn = exportedName(class_name);
	Append(go_name, ccn);
	Delete(ccn);
      }

      // Add the rest of the name, capitalized, dropping the _set or
      // _get.
      String *c1 = removeClassname(name);
      String *c2 = exportedName(c1);
      char *p = Char(c2);
      int len = Len(p);
      for (int i = 0; i < len - 4; ++i) {
	Putc(p[i], go_name);
      }
      Delete(c2);
      Delete(c1);

      if (!checkIgnoredParameters(n, go_name)) {
	Delete(go_name);
	return SWIG_NOWRAP;
      }
    } else if (Cmp(nodetype, "constructor") == 0) {
      is_ctor_dtor = true;

      // Change the name of a constructor to be more Go like.  Change
      // new_ to New, and capitalize the class name.
      assert(Strncmp(name, "new_", 4) == 0);
      String *c1 = NewString(Char(name) + 4);
      String *c2 = exportedName(c1);
      go_name = NewString("New");
      Append(go_name, c2);
      Delete(c2);
      Delete(c1);

      if (Swig_methodclass(n) && Swig_directorclass(n)
	  && Strcmp(Char(Getattr(n, "wrap:action")), director_prot_ctor_code) != 0) {
	// The core SWIG code skips the first parameter when
	// generating the $nondirector_new string.  Recreate the
	// action in this case.  But don't it if we are using the
	// special code for an abstract class.
	String *call = Swig_cppconstructor_call(getClassType(),
						Getattr(n, "parms"));
	SwigType *type = Copy(getClassType());
	SwigType_add_pointer(type);
	String *cres = Swig_cresult(type, Swig_cresult_name(), call);
	Setattr(n, "wrap:action", cres);
      }
    } else if (Cmp(nodetype, "destructor") == 0) {
      // No need to emit protected destructors.
      if (!is_public(n)) {
	return SWIG_OK;
      }

      is_ctor_dtor = true;

      // Change the name of a destructor to be more Go like.  Change
      // delete_ to Delete and capitalize the class name.
      assert(Strncmp(name, "delete_", 7) == 0);
      String *c1 = NewString(Char(name) + 7);
      String *c2 = exportedName(c1);
      go_name = NewString("Delete");
      Append(go_name, c2);
      Delete(c2);
      Delete(c1);

      result = NewString("void");
      r1 = result;
    } else {
      if (!checkFunctionVisibility(n, NULL)) {
	return SWIG_OK;
      }

      go_name = buildGoName(name, is_static, is_friend);

      if (!checkIgnoredParameters(n, go_name)) {
	Delete(go_name);
	return SWIG_NOWRAP;
      }
    }

    String *overname = NULL;
    if (Getattr(n, "sym:overloaded")) {
      overname = Getattr(n, "sym:overname");
    } else {
      String *scope;
      if (!class_name || is_static || is_ctor_dtor) {
	scope = NULL;
      } else {
	scope = NewString("swiggoscope.");
	Append(scope, class_name);
      }
      if (!checkNameConflict(go_name, n, scope)) {
	Delete(go_name);
	return SWIG_NOWRAP;
      }
    }

    String *wname = Swig_name_wrapper(name);
    if (overname) {
      Append(wname, overname);
    }
    Setattr(n, "wrap:name", wname);

    ParmList *parms = Getattr(n, "parms");
    Setattr(n, "wrap:parms", parms);

    int r = makeWrappers(n, name, go_name, overname, wname, NULL, parms, result, is_static);
    if (r != SWIG_OK) {
      return r;
    }

    if (Getattr(n, "sym:overloaded") && !Getattr(n, "sym:nextSibling")) {
      String *scope ;
      if (!class_name || is_static || is_ctor_dtor) {
	scope = NULL;
      } else {
	scope = NewString("swiggoscope.");
	Append(scope, class_name);
      }
      if (!checkNameConflict(go_name, n, scope)) {
	Delete(go_name);
	return SWIG_NOWRAP;
      }

      String *receiver = class_receiver;
      if (is_static || is_ctor_dtor) {
	receiver = NULL;
      }
      r = makeDispatchFunction(n, go_name, receiver, is_static, NULL, false);
      if (r != SWIG_OK) {
	return r;
      }
    }

    Delete(wname);
    Delete(go_name);
    Delete(r1);

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * staticmemberfunctionHandler()
   *
   * For some reason the language code removes the "storage" attribute
   * for a static function before calling functionWrapper, which means
   * that we have no way of knowing whether a function is static or
   * not.  That makes no sense in the Go context.  Here we note that a
   * function is static.
   * ---------------------------------------------------------------------- */

  int staticmemberfunctionHandler(Node *n) {
    assert(!is_static_member_function);
    is_static_member_function = true;
    int r = Language::staticmemberfunctionHandler(n);
    is_static_member_function = false;
    return r;
  }

  /* ----------------------------------------------------------------------
   * makeWrappers()
   *
   * Write out the various function wrappers.
   * n: The function we are emitting.
   * name: The function name.
   * go_name: The name of the function in Go.
   * overname: The overload string for overloaded function.
   * wname: The SWIG wrapped name--the name of the C function.
   * base: A list of the names of base classes, in the case where this
   *       is is a vritual method not defined in the current class.
   * parms: The parameters.
   * result: The result type.
   * is_static: Whether this is a static method or member.
   * ---------------------------------------------------------------------- */

  int makeWrappers(Node *n, String *name, String *go_name, String *overname, String *wname, List *base, ParmList *parms, SwigType *result, bool is_static) {

    assert(result);

    bool needs_wrapper;
    int r = goFunctionWrapper(n, name, go_name, overname, wname, base, parms, result, is_static, &needs_wrapper);
    if (r != SWIG_OK) {
      return r;
    }

    if (!gccgo_flag) {
      r = gcFunctionWrapper(n, name, go_name, overname, wname, parms, result, is_static, needs_wrapper);
      if (r != SWIG_OK) {
	return r;
      }
      r = gccFunctionWrapper(n, base, wname, parms, result);
      if (r != SWIG_OK) {
	return r;
      }
    } else {
      r = gccgoFunctionWrapper(n, base, wname, parms, result);
      if (r != SWIG_OK) {
	return r;
      }
    }

    if (class_methods) {
      Setattr(class_methods, Getattr(n, "name"), NewString(""));
    }

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * goFunctionWrapper()
   *
   * Write out a function wrapper in Go.  When not implementing a
   * method, the actual code is all in C; here we just declare the C
   * function.  When implementing a method, we have to call the C
   * function, because it will have a different name.  If base is not
   * NULL, then we are being called to forward a virtual method to a
   * base class.
   * ---------------------------------------------------------------------- */

  int goFunctionWrapper(Node *n, String *name, String *go_name, String *overname, String *wname, List *base, ParmList *parms, SwigType *result, bool is_static, bool *p_needs_wrapper) {
    Wrapper *dummy = NewWrapper();
    emit_attach_parmmaps(parms, dummy);
    Swig_typemap_attach_parms("default", parms, dummy);
    Swig_typemap_attach_parms("gotype", parms, dummy);
    int parm_count = emit_num_arguments(parms);
    int required_count = emit_num_required(parms);

    String *receiver = class_receiver;
    if (receiver && is_static) {
      receiver = NULL;
    }

    String *nodetype = Getattr(n, "nodeType");
    bool is_constructor = Cmp(nodetype, "constructor") == 0;
    bool is_destructor = Cmp(nodetype, "destructor") == 0;
    if (is_constructor || is_destructor) {
      assert(class_receiver);
      assert(!base);
      receiver = NULL;
    }

    bool add_to_interface = (interfaces && !is_constructor && !is_destructor && !is_static && !overname && checkFunctionVisibility(n, NULL));

    bool needs_wrapper = (gccgo_flag || receiver || is_constructor || is_destructor || parm_count > required_count);

    // See whether any of the function parameters are represented by
    // interface values When calling the C++ code, we need to convert
    // back to a uintptr.
    if (!needs_wrapper) {
      Parm *p = parms;
      for (int i = 0; i < parm_count; ++i) {
	p = getParm(p);
	String *ty = Getattr(p, "type");
	if (goTypeIsInterface(p, ty)) {
	  needs_wrapper = true;
	  break;
	}
	p = nextParm(p);
      }
    }
    if (goTypeIsInterface(n, result)) {
      needs_wrapper = true;
    }

    *p_needs_wrapper = needs_wrapper;

    // If this is a method, first declare the C function we will call.
    // If we do not need a wrapper, then we will only be writing a
    // declaration.
    String *wrapper_name = NULL;
    if (needs_wrapper) {
      wrapper_name = buildGoWrapperName(name, overname);

      if (gccgo_flag && !gccgo_46_flag) {
	Printv(f_go_wrappers, "//extern ", go_prefix, "_", wname, "\n", NULL);
      }

      Printv(f_go_wrappers, "func ", wrapper_name, "(", NULL);
      if (parm_count > required_count) {
	Printv(f_go_wrappers, "int", NULL);
      }
      Parm *p = getParm(parms);
      Swig_cparm_name(p, 0);
      int i = 0;
      if (is_destructor) {
	if (parm_count > required_count) {
	  Printv(f_go_wrappers, ", ", NULL);
	}
	Printv(f_go_wrappers, "uintptr", NULL);
	++i;
	p = nextParm(p);
      } else if (receiver && (base || !is_constructor)) {
	if (parm_count > required_count) {
	  Printv(f_go_wrappers, ", ", NULL);
	}
	Printv(f_go_wrappers, receiver, NULL);
	if (!base) {
	  ++i;
	  p = nextParm(p);
	}
      }
      for (; i < parm_count; ++i) {
	p = getParm(p);
	// Give the parameter a name we will use below.
	Swig_cparm_name(p, i);
	if (i > 0 || (base && receiver) || parm_count > required_count) {
	  Printv(f_go_wrappers, ", ", NULL);
	}
	String *tm = goWrapperType(p, Getattr(p, "type"), false);
	Printv(f_go_wrappers, tm, NULL);
	Delete(tm);
	p = nextParm(p);
      }
      Printv(f_go_wrappers, ")", NULL);
      if (is_constructor) {
	Printv(f_go_wrappers, " ", class_receiver, NULL);
      } else {
	if (SwigType_type(result) != T_VOID) {
	  String *tm = goWrapperType(n, result, true);
	  Printv(f_go_wrappers, " ", tm, NULL);
	  Delete(tm);
	}
      }

      if (gccgo_flag && gccgo_46_flag) {
	Printv(f_go_wrappers, " __asm__ (\"", go_prefix, "_", wname, "\")", NULL);
      }

      Printv(f_go_wrappers, "\n\n", NULL);
    }

    // Start defining the Go function.

    if (!needs_wrapper && gccgo_flag && !gccgo_46_flag) {
      Printv(f_go_wrappers, "//extern ", go_prefix, "_", wname, "\n", NULL);
    }

    Printv(f_go_wrappers, "func ", NULL);

    Parm *p = parms;
    int pi = 0;

    // Add the receiver if this is a method.
    if (receiver) {
      Printv(f_go_wrappers, "(", NULL);
      if (base && receiver) {
	Printv(f_go_wrappers, "_swig_base", NULL);
      } else {
	Printv(f_go_wrappers, Getattr(p, "lname"), NULL);
	p = nextParm(p);
	++pi;
      }
      Printv(f_go_wrappers, " ", receiver, ") ", NULL);
    }

    Printv(f_go_wrappers, go_name, NULL);
    if (overname) {
      Printv(f_go_wrappers, overname, NULL);
    }
    Printv(f_go_wrappers, "(", NULL);

    // If we are doing methods, add this function to the interface.
    if (add_to_interface) {
      Printv(interfaces, "\t", go_name, "(", NULL);
    }

    // Write out the parameters to both the function definition and
    // the interface.

    String *parm_print = NewString("");

    for (; pi < parm_count; ++pi) {
      p = getParm(p);
      if (pi == 0 && is_destructor) {
	String *cl = exportedName(class_name);
	Printv(parm_print, Getattr(p, "lname"), " ", cl, NULL);
	Delete(cl);
      } else {
	if (pi > (receiver && !base ? 1 : 0)) {
	  Printv(parm_print, ", ", NULL);
	}
	if (pi >= required_count) {
	  Printv(parm_print, "_swig_args ...interface{}", NULL);
	  break;
	}
	if (needs_wrapper) {
	  Printv(parm_print, Getattr(p, "lname"), " ", NULL);
	}
	String *tm = goType(p, Getattr(p, "type"));
	Printv(parm_print, tm, NULL);
	Delete(tm);
      }
      p = nextParm(p);
    }

    Printv(parm_print, ")", NULL);

    // Write out the result type.
    if (is_constructor) {
      String *cl = exportedName(class_name);
      Printv(parm_print, " ", cl, NULL);
      Delete(cl);
    } else {
      if (SwigType_type(result) != T_VOID) {
	String *tm = goType(n, result);
	Printv(parm_print, " ", tm, NULL);
	Delete(tm);
      }
    }

    Printv(f_go_wrappers, parm_print, NULL);
    if (add_to_interface) {
      Printv(interfaces, parm_print, "\n", NULL);
    }

    // If this is a wrapper, we need to actually call the C function.
    if (needs_wrapper) {
      Printv(f_go_wrappers, " {\n", NULL);

      if (parm_count > required_count) {
	Parm *p = parms;
	int i;
	for (i = 0; i < required_count; ++i) {
	  p = getParm(p);
	  p = nextParm(p);
	}
	for (; i < parm_count; ++i) {
	  p = getParm(p);
	  String *tm = goType(p, Getattr(p, "type"));
	  Printv(f_go_wrappers, "\tvar ", Getattr(p, "lname"), " ", tm, "\n", NULL);
	  Printf(f_go_wrappers, "\tif len(_swig_args) > %d {\n", i - required_count);
	  Printf(f_go_wrappers, "\t\t%s = _swig_args[%d].(%s)\n", Getattr(p, "lname"), i - required_count, tm);
	  Printv(f_go_wrappers, "\t}\n", NULL);
	  Delete(tm);
	  p = nextParm(p);
	}
      }

      if (gccgo_flag && !gccgo_46_flag) {
	Printv(f_go_wrappers, "\tsyscall.Entersyscall()\n", NULL);
	Printv(f_go_wrappers, "\tdefer syscall.Exitsyscall()\n", NULL);
      }

      Printv(f_go_wrappers, "\t", NULL);
      if (SwigType_type(result) != T_VOID) {
	Printv(f_go_wrappers, "return ", NULL);
      }

      Printv(f_go_wrappers, wrapper_name, "(", NULL);

      if (parm_count > required_count) {
	Printv(f_go_wrappers, "len(_swig_args)", NULL);
      }

      if (base && receiver) {
	if (parm_count > required_count) {
	  Printv(f_go_wrappers, ", ", NULL);
	}
	Printv(f_go_wrappers, "_swig_base", NULL);
      }

      Parm *p = parms;
      for (int i = 0; i < parm_count; ++i) {
	p = getParm(p);
	if (i > 0 || (base && receiver)
	    || parm_count > required_count) {
	  Printv(f_go_wrappers, ", ", NULL);
	}
	Printv(f_go_wrappers, Getattr(p, "lname"), NULL);

	// If this is a destructor, then the C function expects the
	// C++ value, and we have the interface.  We need to get the
	// C++ value.  The same is true for a type represented as an
	// interface.
	if ((i == 0 && is_destructor) || ((i > 0 || !receiver || base || is_constructor) && goTypeIsInterface(p, Getattr(p, "type")))) {
	  Printv(f_go_wrappers, ".Swigcptr()", NULL);
	}

	p = nextParm(p);
      }
      Printv(f_go_wrappers, ")\n", NULL);
      Printv(f_go_wrappers, "}\n", NULL);
    } else {
      if (gccgo_flag && gccgo_46_flag) {
	Printv(f_go_wrappers, " __asm__ (\"", go_prefix, "_", wname, "\")\n", NULL);
      }
    }

    Printv(f_go_wrappers, "\n", NULL);

    Delete(wrapper_name);
    DelWrapper(dummy);

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * gcFunctionWrapper()
   *
   * This is used for 6g/8g, not for gccgo.  Write out the function
   * wrapper which will be compiled with 6c/8c.
   * ---------------------------------------------------------------------- */

  int gcFunctionWrapper(Node *n, String *name, String *go_name, String *overname, String *wname, ParmList *parms, SwigType *result, bool is_static, bool needs_wrapper) {
    Wrapper *f = NewWrapper();

    Printv(f->def, "#pragma dynimport ", wname, " ", wname, " \"\"\n", NULL);
    Printv(f->def, "extern void (*", wname, ")(void*);\n", NULL);
    Printv(f->def, "static void (*x", wname, ")(void*) = ", wname, ";\n", NULL);
    Printv(f->def, "\n", NULL);
    Printv(f->def, "void\n", NULL);

    Wrapper *dummy = NewWrapper();
    emit_attach_parmmaps(parms, dummy);
    Swig_typemap_attach_parms("default", parms, dummy);
    Swig_typemap_attach_parms("gosize", parms, dummy);
    int parm_count = emit_num_arguments(parms);
    int required_count = emit_num_required(parms);

    String *parm_size = NewString("");

    if (parm_count > required_count) {
      Append(parm_size, "SWIG_PARM_SIZE");
    }

    if (class_receiver && !is_static) {
      if (Len(parm_size) > 0) {
	Append(parm_size, " + ");
      }
      Append(parm_size, "SWIG_PARM_SIZE");
    }

    Parm *p = parms;
    for (int i = 0; i < parm_count; ++i) {
      p = getParm(p);
      addGcTypeSize(p, Getattr(p, "type"), parm_size);
      p = nextParm(p);
    }

    if (SwigType_type(result) != T_VOID) {
      addGcTypeSize(n, result, parm_size);
    }

    if (Len(parm_size) == 0) {
      Append(parm_size, "1");
    }

    String *fn_name;
    if (!needs_wrapper) {
      fn_name = Copy(go_name);
      if (overname) {
	Append(fn_name, overname);
      }
    } else {
      fn_name = buildGoWrapperName(name, overname);
    }

    // \xc2\xb7 is UTF-8 for U+00B7 which is Unicode 'Middle Dot'
    Printv(f->def, "\xc2\xb7", fn_name, "(struct { uint8 x[", parm_size, "];} p)", NULL);

    Delete(fn_name);
    Delete(parm_size);

    Printv(f->code, "{\n", NULL);
    Printv(f->code, "\truntime\xc2\xb7" "cgocall(x", wname, ", &p);\n", NULL);
    Printv(f->code, "}\n", NULL);
    Printv(f->code, "\n", NULL);

    Wrapper_print(f, f_gc_wrappers);

    DelWrapper(f);
    DelWrapper(dummy);

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * getGcTypeSize()
   *
   * Return the size to use when passing a type from 6g/8g to 6c/8c.
   * ---------------------------------------------------------------------- */

  String *addGcTypeSize(Node *n, SwigType *type, String *orig) {
    if (Len(orig) > 0) {
      Append(orig, " + ");
    }

    String *go = goType(n, type);
    if (Cmp(go, "string") == 0) {
      // A string has a pointer and a length.
      Append(orig, "(2 * SWIG_PARM_SIZE)");
    } else if (Strncmp(go, "[]", 2) == 0) {
      // A slice has a pointer, a length, and a capacity.  The
      // length and capacity are always 4 bytes.
      Append(orig, "(SWIG_PARM_SIZE + 8)");
    } else if (Strcmp(go, "float64") == 0) {
      Append(orig, "8");
    } else if (Strcmp(go, "complex64") == 0) {
      Append(orig, "8");
    } else if (Strcmp(go, "complex128") == 0) {
      Append(orig, "16");
    } else {
      Append(orig, "SWIG_PARM_SIZE");
    }

    return orig;
  }

  /* ----------------------------------------------------------------------
   * gccFunctionWrapper()
   *
   * This is used for 6g/8g, not for gccgo.  Write out the function
   * wrapper which will be compiled with gcc.  If the base parameter
   * is not NULL, this is calls the base class method rather than
   * executing the SWIG wrapper code.
   * ---------------------------------------------------------------------- */

  int gccFunctionWrapper(Node *n, List *base, String *wname, ParmList *parms, SwigType *result) {
    Wrapper *f = NewWrapper();

    Swig_save("gccFunctionWrapper", n, "parms", NULL);

    Parm *base_parm = NULL;
    if (base && !isStatic(n)) {
      SwigType *base_type = Copy(getClassType());
      SwigType_add_pointer(base_type);
      base_parm = NewParm(base_type, NewString("arg1"), n);
      set_nextSibling(base_parm, parms);
      parms = base_parm;
    }

    emit_parameter_variables(parms, f);
    emit_attach_parmmaps(parms, f);
    int parm_count = emit_num_arguments(parms);
    int required_count = emit_num_required(parms);

    emit_return_variable(n, result, f);

    // Start the function definition.

    Printv(f->def, "void\n", wname, "(void *swig_v)\n", "{\n", NULL);

    // The single function parameter is a pointer to the real argument
    // values.  Define the structure that it points to.

    Printv(f->code, "\tstruct swigargs {\n", NULL);

    if (parm_count > required_count) {
      Printv(f->code, "\t\tint _swig_optargc;\n", NULL);
    }

    Parm *p = parms;
    for (int i = 0; i < parm_count; ++i) {
      p = getParm(p);
      String *ln = Getattr(p, "lname");
      SwigType *pt = Getattr(p, "type");
      String *ct = gcCTypeForGoValue(p, pt, ln);
      Printv(f->code, "\t\t\t", ct, ";\n", NULL);
      Delete(ct);
      p = nextParm(p);
    }
    if (SwigType_type(result) != T_VOID) {
      Printv(f->code, "\t\tlong : 0;\n", NULL);
      String *ln = NewString(Swig_cresult_name());
      String *ct = gcCTypeForGoValue(n, result, ln);
      Delete(ln);
      Printv(f->code, "\t\t", ct, ";\n", NULL);
      Delete(ct);
    }
    Printv(f->code, "\t} *swig_a = (struct swigargs *) swig_v;\n", NULL);

    Printv(f->code, "\n", NULL);

    // Copy the input arguments out of the structure into the
    // parameter variables.

    p = parms;
    for (int i = 0; i < parm_count; ++i) {
      p = getParm(p);

      String *tm = Getattr(p, "tmap:in");
      if (!tm) {
	Swig_warning(WARN_TYPEMAP_IN_UNDEF, input_file, line_number, "Unable to use type %s as a function argument\n", SwigType_str(Getattr(p, "type"), 0));
      } else {
	String *ln = Getattr(p, "lname");
	String *input = NewString("");
	Printv(input, "swig_a->", ln, NULL);
	Replaceall(tm, "$input", input);
	Setattr(p, "emit:input", input);
	if (i < required_count) {
	  Printv(f->code, "\t", tm, "\n", NULL);
	} else {
	  Printf(f->code, "\tif (swig_a->_swig_optargc > %d) {\n", i - required_count);
	  Printv(f->code, "\t\t", tm, "\n", NULL);
	  Printv(f->code, "\t}\n", NULL);
	}
      }
      p = nextParm(p);
    }

    Printv(f->code, "\n", NULL);

    // Do the real work of the function.

    checkConstraints(parms, f);

    emitGoAction(n, base, parms, result, f);

    argout(parms, f);

    cleanupFunction(n, f, parms);

    Printv(f->code, "}\n", NULL);

    Wrapper_print(f, f_c_wrappers);

    Swig_restore(n);

    DelWrapper(f);
    Delete(base_parm);

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * gccgoFunctionWrapper()
   *
   * This is used for gccgo, not 6g/8g.  Write out the function
   * wrapper which will be compiled with gcc.  If the base parameter
   * is not NULL, this is calls the base class method rather than
   * executing the SWIG wrapper code.
   * ---------------------------------------------------------------------- */

  int gccgoFunctionWrapper(Node *n, List *base, String *wname, ParmList *parms, SwigType *result) {
    Wrapper *f = NewWrapper();

    Swig_save("gccgoFunctionWrapper", n, "parms", NULL);

    Parm *base_parm = NULL;
    if (base && !isStatic(n)) {
      SwigType *base_type = Copy(getClassType());
      SwigType_add_pointer(base_type);
      base_parm = NewParm(base_type, NewString("arg1"), n);
      set_nextSibling(base_parm, parms);
      parms = base_parm;
    }

    emit_parameter_variables(parms, f);
    emit_attach_parmmaps(parms, f);
    int parm_count = emit_num_arguments(parms);
    int required_count = emit_num_required(parms);

    emit_return_variable(n, result, f);

    // Start the function definition.

    String *fnname = NewString("");
    Printv(fnname, go_prefix, "_", wname, "(", NULL);

    if (parm_count > required_count) {
      Printv(fnname, "int _swig_optargc", NULL);
    }

    Parm *p = parms;
    for (int i = 0; i < parm_count; ++i) {
      p = getParm(p);
      SwigType *pt = Copy(Getattr(p, "type"));
      if (SwigType_isarray(pt)) {
	SwigType_del_array(pt);
	SwigType_add_pointer(pt);
      }
      String *pn = NewString("g");
      Append(pn, Getattr(p, "lname"));
      String *ct = gccgoCTypeForGoValue(p, pt, pn);
      if (i > 0 || parm_count > required_count) {
	Printv(fnname, ", ", NULL);
      }
      Printv(fnname, ct, NULL);
      Delete(ct);
      Delete(pn);
      Delete(pt);
      p = nextParm(p);
    }

    Printv(fnname, ")", NULL);

    if (SwigType_type(result) == T_VOID) {
      Printv(f->def, "void ", fnname, NULL);
    } else {
      String *ct = gccgoCTypeForGoValue(n, result, fnname);
      Printv(f->def, ct, NULL);
      Delete(ct);
    }

    Printv(f->def, " {\n", NULL);

    Delete(fnname);

    if (SwigType_type(result) != T_VOID) {
      String *ln = NewString("go_result");
      String *ct = gccgoCTypeForGoValue(n, result, ln);
      Wrapper_add_local(f, "go_result", ct);
      Delete(ct);
      Delete(ln);
    }

    // Copy the parameters into the variables which hold their values,
    // applying appropriate transformations.

    p = parms;
    for (int i = 0; i < parm_count; ++i) {
      p = getParm(p);

      String *tm = Getattr(p, "tmap:in");
      if (!tm) {
	Swig_warning(WARN_TYPEMAP_IN_UNDEF, input_file, line_number,
		     "Unable to use type %s as a function argument\n", SwigType_str(Getattr(p, "type"), 0));
      } else {
	String *ln = Getattr(p, "lname");
	String *pn = NewString("g");
	Append(pn, ln);
	Replaceall(tm, "$input", pn);
	Setattr(p, "emit:input", pn);
	if (i < required_count) {
	  Printv(f->code, "  ", tm, "\n", NULL);
	} else {
	  Printf(f->code, "  if (_swig_optargc > %d) {\n", i - required_count);
	  Printv(f->code, "    ", tm, "\n", NULL);
	  Printv(f->code, "  }\n", NULL);
	}
      }

      p = nextParm(p);
    }

    Printv(f->code, "\n", NULL);

    // Do the real work of the function.

    checkConstraints(parms, f);

    emitGoAction(n, base, parms, result, f);

    argout(parms, f);

    cleanupFunction(n, f, parms);

    if (SwigType_type(result) != T_VOID) {
      Printv(f->code, "  return go_result;\n", NULL);
    }

    Printv(f->code, "}\n", NULL);

    Wrapper_print(f, f_c_wrappers);

    Swig_restore(n);

    DelWrapper(f);
    Delete(base_parm);

    return SWIG_OK;
  }

  /* -----------------------------------------------------------------------
   * checkConstraints()
   *
   * Check parameter constraints if any.  This is used for the C/C++
   * function.  This assumes that each parameter has an "emit:input"
   * property with the name to use to refer to that parameter.
   * ----------------------------------------------------------------------- */

  void checkConstraints(ParmList *parms, Wrapper *f) {
    Parm *p = parms;
    while (p) {
      String *tm = Getattr(p, "tmap:check");
      if (!tm) {
	p = nextSibling(p);
      } else {
	Replaceall(tm, "$input", Getattr(p, "emit:input"));
	Printv(f->code, tm, "\n\n", NULL);
	p = Getattr(p, "tmap:check:next");
      }
    }
  }

  /* -----------------------------------------------------------------------
   * getGoAction()
   *
   * Get the action of the function.  This is used for C/C++ function.
   * ----------------------------------------------------------------------- */

  void emitGoAction(Node *n, List *base, ParmList *parms, SwigType *result, Wrapper *f) {
    String *actioncode;
    if (!base || isStatic(n)) {
      Swig_director_emit_dynamic_cast(n, f);
      actioncode = emit_action(n);
    } else {
      // Call the base class method.
      actioncode = NewString("");

      String *current = NewString("");
      if (!gccgo_flag) {
	Printv(current, "swig_a->", NULL);
      }
      Printv(current, Getattr(parms, "lname"), NULL);

      int vc = 0;
      for (Iterator bi = First(base); bi.item; bi = Next(bi)) {
	Printf(actioncode, "  %s *swig_b%d = (%s *)%s;\n", bi.item, vc, bi.item, current);
	Delete(current);
	current = NewString("");
	Printf(current, "swig_b%d", vc);
	++vc;
      }

      String *code = Copy(Getattr(n, "wrap:action"));
      Replaceall(code, Getattr(parms, "lname"), current);
      Printv(actioncode, code, "\n", NULL);
    }

    Swig_save("emitGoAction", n, "type", "tmap:out", NULL);

    Setattr(n, "type", result);

    String *tm = Swig_typemap_lookup_out("out", n, Swig_cresult_name(), f, actioncode);
    if (!tm) {
      Swig_warning(WARN_TYPEMAP_OUT_UNDEF, input_file, line_number, "Unable to use return type %s\n", SwigType_str(result, 0));
    } else {
      if (!gccgo_flag) {
	static const String *swig_a_result = NewStringf("swig_a->%s", Swig_cresult_name());
	Replaceall(tm, "$result", swig_a_result);
      } else {
	Replaceall(tm, "$result", "go_result");
      }
      if (GetFlag(n, "feature:new")) {
	Replaceall(tm, "$owner", "1");
      } else {
	Replaceall(tm, "$owner", "0");
      }
      Printv(f->code, tm, "\n", NULL);
      Delete(tm);
    }

    Swig_restore(n);
  }

  /* -----------------------------------------------------------------------
   * argout()
   *
   * Handle argument output code if any.  This is used for the C/C++
   * function.  This assumes that each parameter has an "emit:input"
   * property with the name to use to refer to that parameter.
   * ----------------------------------------------------------------------- */

  void argout(ParmList *parms, Wrapper *f) {
    Parm *p = parms;
    while (p) {
      String *tm = Getattr(p, "tmap:argout");
      if (!tm) {
	p = nextSibling(p);
      } else {
	Replaceall(tm, "$result", Swig_cresult_name());
	Replaceall(tm, "$input", Getattr(p, "emit:input"));
	Printv(f->code, tm, "\n", NULL);
	p = Getattr(p, "tmap:argout:next");
      }
    }
  }

  /* -----------------------------------------------------------------------
   * freearg()
   *
   * Handle argument cleanup code if any.  This is used for the C/C++
   * function.  This assumes that each parameter has an "emit:input"
   * property with the name to use to refer to that parameter.
   * ----------------------------------------------------------------------- */

  String *freearg(ParmList *parms) {
    String *ret = NewString("");
    Parm *p = parms;
    while (p) {
      String *tm = Getattr(p, "tmap:freearg");
      if (!tm) {
	p = nextSibling(p);
      } else {
	Replaceall(tm, "$input", Getattr(p, "emit:input"));
	Printv(ret, tm, "\n", NULL);
	p = Getattr(p, "tmap:freearg:next");
      }
    }
    return ret;
  }

  /* -----------------------------------------------------------------------
   * cleanupFunction()
   *
   * Final function cleanup code.
   * ----------------------------------------------------------------------- */

  void cleanupFunction(Node *n, Wrapper *f, ParmList *parms) {
    String *cleanup = freearg(parms);
    Printv(f->code, cleanup, NULL);

    if (GetFlag(n, "feature:new")) {
      String *tm = Swig_typemap_lookup("newfree", n, Swig_cresult_name(), 0);
      if (tm) {
	Replaceall(tm, "$source", Swig_cresult_name());
	Printv(f->code, tm, "\n", NULL);
	Delete(tm);
      }
    }

    Replaceall(f->code, "$cleanup", cleanup);
    Delete(cleanup);

    Replaceall(f->code, "$symname", Getattr(n, "sym:name"));
  }

  /* -----------------------------------------------------------------------
   * variableHandler()
   *
   * This exists just to set the making_variable_wrappers flag.
   * ----------------------------------------------------------------------- */

  virtual int variableHandler(Node *n) {
    assert(!making_variable_wrappers);
    making_variable_wrappers = true;
    int r = Language::variableHandler(n);
    making_variable_wrappers = false;
    return r;
  }

  /* -----------------------------------------------------------------------
   * constantWrapper()
   *
   * Product a const declaration.
   * ------------------------------------------------------------------------ */

  virtual int constantWrapper(Node *n) {
    SwigType *type = Getattr(n, "type");

    if (!SwigType_issimple(type) && SwigType_type(type) != T_STRING) {
      return goComplexConstant(n, type);
    }

    if (Getattr(n, "storage") && Strcmp(Getattr(n, "storage"), "static") == 0) {
      return goComplexConstant(n, type);
    }

    String *go_name = buildGoName(Getattr(n, "sym:name"), false, false);

    String *tm = goType(n, type);
    String *value = Getattr(n, "value");

    String *copy = NULL;
    if (SwigType_type(type) == T_BOOL) {
      if (Cmp(value, "true") != 0 && Cmp(value, "false") != 0) {
	return goComplexConstant(n, type);
      }
    } else if (SwigType_type(type) == T_STRING || SwigType_type(type) == T_CHAR) {
      // Backslash sequences are somewhat different in Go and C/C++.
      if (Strchr(value, '\\') != 0) {
	return goComplexConstant(n, type);
      }
    } else {
      // Accept a 0x prefix, and strip combinations of u and l
      // suffixes.  Otherwise accept digits, decimal point, and
      // exponentiation.  Treat anything else as too complicated to
      // handle as a Go constant.
      char *p = Char(value);
      int len = strlen(p);
      bool need_copy = false;
      while (len > 0) {
	char c = p[len - 1];
	if (c != 'l' && c != 'L' && c != 'u' && c != 'U') {
	  break;
	}
	--len;
	need_copy = true;
      }
      bool is_hex = false;
      int i = 0;
      if (p[0] == '0' && (p[1] == 'x' || p[1] == 'X')) {
	i = 2;
	is_hex = true;
      }
      for (; i < len; ++i) {
	switch (p[i]) {
	case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9':
	  break;
	case 'a': case 'b': case 'c': case 'd': case 'f': case 'A': case 'B': case 'C': case 'D': case 'F':
	  if (!is_hex) {
	    return goComplexConstant(n, type);
	  }
	  break;
	case '.': case 'e': case 'E': case '+': case '-':
	  break;
	default:
	  return goComplexConstant(n, type);
	}
      }
      if (need_copy) {
	copy = Copy(value);
	Replaceall(copy, p + len, "");
	value = copy;
      }
    }

    if (!checkNameConflict(go_name, n, NULL)) {
      Delete(tm);
      Delete(go_name);
      Delete(copy);
      return SWIG_NOWRAP;
    }

    Printv(f_go_wrappers, "const ", go_name, " ", tm, " = ", NULL);
    if (SwigType_type(type) == T_STRING) {
      Printv(f_go_wrappers, "\"", value, "\"", NULL);
    } else if (SwigType_type(type) == T_CHAR) {
      Printv(f_go_wrappers, "'", value, "'", NULL);
    } else {
      Printv(f_go_wrappers, value, NULL);
    }

    Printv(f_go_wrappers, "\n", NULL);

    Delete(tm);
    Delete(go_name);
    Delete(copy);

    return SWIG_OK;
  }

  /* ----------------------------------------------------------------------
   * enumDeclaration()
   *
   * A C++ enum type turns into a Named go int type.
   * ---------------------------------------------------------------------- */

  virtual int enumDeclaration(Node *n) {
    String *name = goEnumName(n);
    if (Strcmp(name, "int") != 0) {
      if (!ImportMode || !imported_package) {
	if (!checkNameConflict(name, n, NULL)) {
	  Delete(name);
	  return SWIG_NOWRAP;
	}
	Printv(f_go_wrappers, "type ", name, " int\n", NULL);
      } else {
	String *nw = NewString("");
	Printv(nw, imported_package, ".", name, NULL);
	Setattr(n, "go:enumname", nw);
      }
    }
    Delete(name);

    return Language::enumDeclaration(n);
  }

  /* -----------------------------------------------------------------------
   * enumvalueDeclaration()
   *
   * Declare a single value of an enum type.  We fetch the value by
   * calling a C/C++ function.
   * ------------------------------------------------------------------------ */

  virtual int enumvalueDeclaration(Node *n) {
    if (!is_public(n)) {
      return SWIG_OK;
    }
    if (Getattr(parentNode(n), "unnamed")) {
      Setattr(n, "type", NewString("…