gcc/config/darwin-crt2.c

   1 /* KeyMgr backwards-compatibility support for Darwin.
   2    Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 2, or (at your option) any later
   9 version.
  10
  11 In addition to the permissions in the GNU General Public License, the
  12 Free Software Foundation gives you unlimited permission to link the
  13 compiled version of this file into combinations with other programs,
  14 and to distribute those combinations without any restriction coming
  15 from the use of this file.  (The General Public License restrictions
  16 do apply in other respects; for example, they cover modification of
  17 the file, and distribution when not linked into a combine
  18 executable.)
  19
  20 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  21 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  22 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  23 for more details.
  24
  25 You should have received a copy of the GNU General Public License
  26 along with GCC; see the file COPYING.  If not, write to the Free
  27 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  28 02111-1307, USA.  */
  29
  30 /* It is incorrect to include config.h here, because this file is being
  31    compiled for the target, and hence definitions concerning only the host
  32    do not apply.  */
  33
  34 #include "tconfig.h"
  35 #include "tsystem.h"
  36
  37 /* This file doesn't do anything useful on non-powerpc targets, since they
  38    don't have backwards compatibility anyway.  */
  39
  40 #ifdef __ppc__
  41
  42 /* Homemade decls substituting for getsect.h and dyld.h, so cross
  43    compilation works.  */
  44 struct mach_header;
  45 extern char *getsectdatafromheader (struct mach_header *, const char *,
  46                                     const char *, unsigned long *);
  47 extern void _dyld_register_func_for_add_image
  48   (void (*) (struct mach_header *, unsigned long));
  49 extern void _dyld_register_func_for_remove_image
  50   (void (*) (struct mach_header *, unsigned long));
  51
  52 extern void __darwin_gcc3_preregister_frame_info (void);
  53
  54 /* These are from "keymgr.h".  */
  55 extern void _init_keymgr (void);
  56 extern void *_keymgr_get_and_lock_processwide_ptr (unsigned key);
  57 extern void _keymgr_set_and_unlock_processwide_ptr (unsigned key, void *ptr);
  58
  59 extern void *__keymgr_global[];
  60 typedef struct _Sinfo_Node {
  61         unsigned int size ;             /*size of this node*/
  62         unsigned short major_version ;  /*API major version.*/
  63         unsigned short minor_version ;  /*API minor version.*/
  64         } _Tinfo_Node ;
  65
  66 /* KeyMgr 3.x is the first one supporting GCC3 stuff natively.  */
  67 #define KEYMGR_API_MAJOR_GCC3           3
  68 /* ... with these keys.  */
  69 #define KEYMGR_GCC3_LIVE_IMAGE_LIST     301     /* loaded images  */
  70 #define KEYMGR_GCC3_DW2_OBJ_LIST        302     /* Dwarf2 object list  */
  71
  72 /* Node of KEYMGR_GCC3_LIVE_IMAGE_LIST.  Info about each resident image.  */
  73 struct live_images {
  74   unsigned long this_size;                      /* sizeof (live_images)  */
  75   struct mach_header *mh;                       /* the image info  */
  76   unsigned long vm_slide;
  77   void (*destructor)(struct live_images *);     /* destructor for this  */
  78   struct live_images *next;
  79   unsigned int examined_p;
  80   void *fde;
  81   void *object_info;
  82   unsigned long info[2];                        /* Future use.  */
  83 };
  84
  85 \f
  86 /* These routines are used only on Darwin versions before 10.2.
  87    Later versions have equivalent code in the system.
  88    Eventually, they might go away, although it might be a long time...  */
  89
  90 static void darwin_unwind_dyld_remove_image_hook
  91   (struct mach_header *m, unsigned long s);
  92 static void darwin_unwind_dyld_remove_image_hook
  93   (struct mach_header *m, unsigned long s);
  94 extern void __darwin_gcc3_preregister_frame_info (void);
  95
  96 static void
  97 darwin_unwind_dyld_add_image_hook (struct mach_header *mh, unsigned long slide)
  98 {
  99   struct live_images *l = (struct live_images *)calloc (1, sizeof (*l));
 100   l->mh = mh;
 101   l->vm_slide = slide;
 102   l->this_size = sizeof (*l);
 103   l->next = (struct live_images *)
 104         _keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
 105   _keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST, l);
 106 }
 107
 108 static void
 109 darwin_unwind_dyld_remove_image_hook (struct mach_header *m, unsigned long s)
 110 {
 111   struct live_images *top, **lip, *destroy = NULL;
 112
 113   /* Look for it in the list of live images and delete it.  */
 114
 115   top = (struct live_images *)
 116            _keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
 117   for (lip = &top; *lip != NULL; lip = &(*lip)->next)
 118     {
 119       if ((*lip)->mh == m && (*lip)->vm_slide == s)
 120         {
 121           destroy = *lip;
 122           *lip = destroy->next;                 /* unlink DESTROY  */
 123
 124           if (destroy->this_size != sizeof (*destroy))  /* sanity check  */
 125             abort ();
 126
 127           break;
 128         }
 129     }
 130   _keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST, top);
 131
 132   /* Now that we have unlinked this from the image list, toss it.  */
 133   if (destroy != NULL)
 134     {
 135       if (destroy->destructor != NULL)
 136         (*destroy->destructor) (destroy);
 137       free (destroy);
 138     }
 139 }
 140
 141 void
 142 __darwin_gcc3_preregister_frame_info (void)
 143 {
 144   const _Tinfo_Node *info;
 145   _init_keymgr ();
 146   info = (_Tinfo_Node *)__keymgr_global[2];
 147   if (info != NULL)
 148     {
 149       if (info->major_version >= KEYMGR_API_MAJOR_GCC3)
 150         return;
 151       /* Otherwise, use our own add_image_hooks.  */
 152     }
 153
 154   _dyld_register_func_for_add_image (darwin_unwind_dyld_add_image_hook);
 155   _dyld_register_func_for_remove_image (darwin_unwind_dyld_remove_image_hook);
 156 }
 157
 158 #endif  /* __ppc__ */