libjava/darwin.cc

   1 /* darwin.cc - class loader stuff for Darwin.  */
   2
   3 /* Copyright (C) 2004, 2007  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 #if !defined (__LP64__)
  25   struct mach_header;
  26 # define JAVA_MACH_HEADER mach_header
  27 # define  mh_size_t uint32_t
  28   extern "C" void _dyld_register_func_for_add_image
  29     (void (*func)(const struct mach_header *mh, intptr_t vmaddr_slide));
  30   extern "C" void _dyld_register_func_for_remove_image
  31     (void (*func)(const struct mach_header *mh, intptr_t vmaddr_slide));
  32   extern "C" char *getsectdatafromheader
  33     (const struct mach_header *mhp, const char *segname, const char *sectname,
  34      uint32_t *size);
  35 # define GETSECTDATA getsectdatafromheader
  36 #else
  37   struct mach_header_64;
  38 # define JAVA_MACH_HEADER mach_header_64
  39 # define mh_size_t uint64_t
  40   extern "C" void _dyld_register_func_for_add_image
  41     (void (*func)(const struct mach_header_64 *mh, intptr_t vmaddr_slide));
  42   extern "C" void _dyld_register_func_for_remove_image
  43     (void (*func)(const struct mach_header_64 *mh, intptr_t vmaddr_slide));
  44   extern "C" char *getsectdatafromheader_64
  45     (const struct mach_header_64 *mhp, const char *segname,
  46      const char *sectname, uint64_t *size);
  47 # define GETSECTDATA getsectdatafromheader_64
  48 #endif
  49
  50 /* When a new image is loaded, look to see if it has a jcr section
  51    and if so register the classes listed in it.  */
  52
  53 static void
  54 darwin_java_register_dyld_add_image_hook (const struct JAVA_MACH_HEADER *mh,
  55                                           intptr_t slide)
  56 {
  57   char *fde;
  58   mh_size_t sz;
  59
  60   fde = GETSECTDATA (mh, "__DATA", "jcr", &sz);
  61   if (! fde)
  62     return;
  63
  64   /* As far as I can tell, you're only supposed to load shared
  65      libraries while having a lock on java.lang.Class.  So there's
  66      no need to synchronize on anything here.  (I'm not sure how exactly
  67      you can ensure this given lazy library loading.  FIXME.)  */
  68
  69   _Jv_RegisterClasses_Counted ((const jclass *) (fde + slide),
  70                                sz / sizeof (jclass *));
  71 }
  72
  73 static struct darwin_constructor_s{
  74   darwin_constructor_s()
  75   {
  76     _dyld_register_func_for_add_image
  77       (darwin_java_register_dyld_add_image_hook);
  78     /* At present, you mustn't unload any java plugin.  */
  79   };
  80 } darwin_constructor;