libjava/darwin.cc

   1 /* darwin.cc - class loader stuff for Darwin.  */
   2
   3 /* Copyright (C) 2004  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 #include <config.h>
  12
  13 #include <jvm.h>
  14
  15 /* In theory, we should be able to do:
  16    #include <mach-o/getsect.h>
  17    #include <mach-o/dyld.h>
  18
  19    but all the types in these headers changed between Panther and Tiger,
  20    so the only way to be avoid type mismatches is to declare the routines
  21    ourself.  */
  22
  23 #include <stdint.h>
  24 struct mach_header;
  25 extern "C" void _dyld_register_func_for_add_image
  26   (void (*func)(const struct mach_header *mh, intptr_t vmaddr_slide));
  27 extern "C" void _dyld_register_func_for_remove_image
  28   (void (*func)(const struct mach_header *mh, intptr_t vmaddr_slide));
  29 extern "C" char *getsectdatafromheader
  30 (const struct mach_header *mhp, const char *segname, const char *sectname,
  31  uint32_t *size);
  32
  33 /* When a new image is loaded, look to see if it has a jcr section
  34    and if so register the classes listed in it.  */
  35
  36 static void
  37 darwin_java_register_dyld_add_image_hook (const struct mach_header *mh,
  38                                           intptr_t slide)
  39 {
  40   char *fde;
  41   uint32_t sz;
  42
  43   fde = getsectdatafromheader (mh, "__DATA", "jcr", &sz);
  44   if (! fde)
  45     return;
  46
  47   /* As far as I can tell, you're only supposed to load shared
  48      libraries while having a lock on java.lang.Class.  So there's
  49      no need to synchronize on anything here.  (I'm not sure how exactly
  50      you can ensure this given lazy library loading.  FIXME.)  */
  51
  52   _Jv_RegisterClasses_Counted ((const jclass *) (fde + slide),
  53                                sz / sizeof (jclass *));
  54 }
  55
  56 static struct darwin_constructor_s{
  57   darwin_constructor_s()
  58   {
  59     _dyld_register_func_for_add_image
  60       (darwin_java_register_dyld_add_image_hook);
  61     /* At present, you mustn't unload any java plugin.  */
  62   };
  63 } darwin_constructor;