| 1 | /* Dynamic loading of the libgcc unwinder. Generic version. |
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| 2 | Copyright (C) 2021-2022 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #ifndef _UNWIND_LINK_H |
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| 20 | #define _UNWIND_LINK_H |
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| 21 | |
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| 22 | #include <unwind.h> |
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| 23 | #include <unwind-arch.h> |
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| 24 | |
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| 25 | #if !UNWIND_LINK_FRAME_ADJUSTMENT |
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| 26 | static inline void * |
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| 27 | unwind_arch_adjustment (void *prev, void *addr) |
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| 28 | { |
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| 29 | return addr; |
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| 30 | } |
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| 31 | #endif |
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| 32 | |
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| 33 | #ifdef SHARED |
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| 34 | # include <sysdep.h> |
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| 35 | # include <unwind-resume.h> |
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| 36 | |
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| 37 | # if UNWIND_LINK_FRAME_STATE_FOR |
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| 38 | struct frame_state; |
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| 39 | # endif |
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| 40 | |
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| 41 | struct unwind_link |
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| 42 | { |
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| 43 | __typeof (_Unwind_Backtrace) *ptr__Unwind_Backtrace; |
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| 44 | __typeof (_Unwind_ForcedUnwind) *ptr__Unwind_ForcedUnwind; |
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| 45 | __typeof (_Unwind_GetCFA) *ptr__Unwind_GetCFA; |
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| 46 | # if UNWIND_LINK_GETIP |
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| 47 | __typeof (_Unwind_GetIP) *ptr__Unwind_GetIP; |
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| 48 | # endif |
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| 49 | __typeof (_Unwind_Resume) *ptr__Unwind_Resume; |
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| 50 | #if UNWIND_LINK_FRAME_STATE_FOR |
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| 51 | struct frame_state *(*ptr___frame_state_for) (void *, struct frame_state *); |
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| 52 | #endif |
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| 53 | _Unwind_Reason_Code (*ptr_personality) PERSONALITY_PROTO; |
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| 54 | UNWIND_LINK_EXTRA_FIELDS |
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| 55 | }; |
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| 56 | |
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| 57 | /* Return a pointer to the implementation, or NULL on failure. */ |
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| 58 | struct unwind_link *__libc_unwind_link_get (void); |
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| 59 | libc_hidden_proto (__libc_unwind_link_get) |
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| 60 | |
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| 61 | /* UNWIND_LINK_PTR returns the stored function pointer NAME from the |
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| 62 | cached unwind link OBJ (which was previously returned by |
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| 63 | __libc_unwind_link_get). */ |
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| 64 | # ifdef PTR_DEMANGLE |
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| 65 | # define UNWIND_LINK_PTR(obj, name, ...) \ |
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| 66 | ({ \ |
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| 67 | __typeof ((obj)->ptr_##name) __unwind_fptr = (obj)->ptr_##name; \ |
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| 68 | PTR_DEMANGLE (__unwind_fptr); \ |
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| 69 | __unwind_fptr; \ |
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| 70 | }) |
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| 71 | # else /* !PTR_DEMANGLE */ |
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| 72 | # define UNWIND_LINK_PTR(obj, name, ...) ((obj)->ptr_##name) |
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| 73 | # endif |
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| 74 | |
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| 75 | /* Called from fork, in the new subprocess. */ |
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| 76 | void __libc_unwind_link_after_fork (void); |
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| 77 | |
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| 78 | /* Called from __libc_freeres. */ |
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| 79 | void __libc_unwind_link_freeres (void) attribute_hidden; |
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| 80 | |
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| 81 | #else /* !SHARED */ |
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| 82 | |
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| 83 | /* Dummy implementation so that the code can be shared with the SHARED |
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| 84 | version. */ |
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| 85 | struct unwind_link; |
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| 86 | static inline struct unwind_link * |
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| 87 | __libc_unwind_link_get (void) |
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| 88 | { |
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| 89 | /* Return something that is not a null pointer, so that error checks |
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| 90 | succeed. */ |
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| 91 | return (struct unwind_link *) 1; |
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| 92 | } |
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| 93 | |
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| 94 | /* Directly call the static implementation. */ |
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| 95 | # define UNWIND_LINK_PTR(obj, name, ...) \ |
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| 96 | ((void) (obj), &name) |
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| 97 | |
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| 98 | static inline void |
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| 99 | __libc_unwind_link_after_fork (void) |
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| 100 | { |
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| 101 | /* No need to clean up if the unwinder is statically linked. */ |
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| 102 | } |
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| 103 | |
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| 104 | #endif /* !SHARED */ |
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| 105 | |
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| 106 | #endif /* _UNWIND_LINK_H */ |
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| 107 | |
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