gcc/config/darwin-crt2.c

   1 /* KeyMgr backwards-compatibility support for Darwin.
   2    Copyright (C) 2001, 2002 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 /* Homemade decls substituting for getsect.h and dyld.h, so cross
  38    compilation works.  */
  39 struct mach_header;
  40 extern char *getsectdatafromheader (struct mach_header *, const char *,
  41                                     const char *, unsigned long *);
  42 extern void _dyld_register_func_for_add_image
  43   (void (*) (struct mach_header *, unsigned long));
  44 extern void _dyld_register_func_for_remove_image
  45   (void (*) (struct mach_header *, unsigned long));
  46
  47 extern void __darwin_gcc3_preregister_frame_info (void);
  48
  49 /* These are from "keymgr.h".  */
  50 extern void _init_keymgr (void);
  51 extern void *_keymgr_get_and_lock_processwide_ptr (unsigned key);
  52 extern void _keymgr_set_and_unlock_processwide_ptr (unsigned key, void *ptr);
  53
  54 extern void *__keymgr_global[];
  55 typedef struct _Sinfo_Node {
  56         unsigned int size ;             /*size of this node*/
  57         unsigned short major_version ;  /*API major version.*/
  58         unsigned short minor_version ;  /*API minor version.*/
  59         } _Tinfo_Node ;
  60
  61 /* KeyMgr 3.x is the first one supporting GCC3 stuff natively.  */
  62 #define KEYMGR_API_MAJOR_GCC3           3
  63 /* ... with these keys.  */
  64 #define KEYMGR_GCC3_LIVE_IMAGE_LIST     301     /* loaded images  */
  65 #define KEYMGR_GCC3_DW2_OBJ_LIST        302     /* Dwarf2 object list  */
  66
  67 /* Node of KEYMGR_GCC3_LIVE_IMAGE_LIST.  Info about each resident image.  */
  68 struct live_images {
  69   unsigned long this_size;                      /* sizeof (live_images)  */
  70   struct mach_header *mh;                       /* the image info  */
  71   unsigned long vm_slide;
  72   void (*destructor)(struct live_images *);     /* destructor for this  */
  73   struct live_images *next;
  74   unsigned int examined_p;
  75   void *fde;
  76   void *object_info;
  77   unsigned long info[2];                        /* Future use.  */
  78 };
  79
  80 \f
  81 /* These routines are used only on Darwin versions before 10.2.
  82    Later versions have equivalent code in the system.
  83    Eventually, they might go away, although it might be a long time...  */
  84
  85 static void darwin_unwind_dyld_remove_image_hook
  86   (struct mach_header *m, unsigned long s);
  87 static void darwin_unwind_dyld_remove_image_hook
  88   (struct mach_header *m, unsigned long s);
  89 extern void __darwin_gcc3_preregister_frame_info (void);
  90
  91 static void
  92 darwin_unwind_dyld_add_image_hook (struct mach_header *mh, unsigned long slide)
  93 {
  94   struct live_images *l = (struct live_images *)calloc (1, sizeof (*l));
  95   l->mh = mh;
  96   l->vm_slide = slide;
  97   l->this_size = sizeof (*l);
  98   l->next = (struct live_images *)
  99         _keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
 100   _keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST, l);
 101 }
 102
 103 static void
 104 darwin_unwind_dyld_remove_image_hook (struct mach_header *m, unsigned long s)
 105 {
 106   struct live_images *top, **lip, *destroy = NULL;
 107
 108   /* Look for it in the list of live images and delete it.  */
 109
 110   top = (struct live_images *)
 111            _keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
 112   for (lip = &top; *lip != NULL; lip = &(*lip)->next)
 113     {
 114       if ((*lip)->mh == m && (*lip)->vm_slide == s)
 115         {
 116           destroy = *lip;
 117           *lip = destroy->next;                 /* unlink DESTROY  */
 118
 119           if (destroy->this_size != sizeof (*destroy))  /* sanity check  */
 120             abort ();
 121
 122           break;
 123         }
 124     }
 125   _keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST, top);
 126
 127   /* Now that we have unlinked this from the image list, toss it.  */
 128   if (destroy != NULL)
 129     {
 130       if (destroy->destructor != NULL)
 131         (*destroy->destructor) (destroy);
 132       free (destroy);
 133     }
 134 }
 135
 136 void
 137 __darwin_gcc3_preregister_frame_info (void)
 138 {
 139   const _Tinfo_Node *info;
 140   _init_keymgr ();
 141   info = (_Tinfo_Node *)__keymgr_global[2];
 142   if (info != NULL)
 143     {
 144       if (info->major_version >= KEYMGR_API_MAJOR_GCC3)
 145         return;
 146       /* Otherwise, use our own add_image_hooks.  */
 147     }
 148
 149   _dyld_register_func_for_add_image (darwin_unwind_dyld_add_image_hook);
 150   _dyld_register_func_for_remove_image (darwin_unwind_dyld_remove_image_hook);
 151 }