1 /* KeyMgr backwards-compatibility support for Darwin.
2 Copyright (C) 2001-2023 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 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 Under Section 7 of GPL version 3, you are granted additional
17 permissions described in the GCC Runtime Library Exception, version
18 3.1, as published by the Free Software Foundation.
19
20 You should have received a copy of the GNU General Public License and
21 a copy of the GCC Runtime Library Exception along with this program;
22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 <http://www.gnu.org/licenses/>. */
24
25 /* It is incorrect to include config.h here, because this file is being
26 compiled for the target, and hence definitions concerning only the host
27 do not apply. */
28
29 #include "tconfig.h"
30 #include "tsystem.h"
31
32 /* This file doesn't do anything useful on non-powerpc targets, since they
33 don't have backwards compatibility anyway. */
34
35 #ifdef __ppc__
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
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 = ⊤ *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 }
152
153 #endif /* __ppc__ */