1 | /* Copyright (C) 2005-2022 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library. If not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <link.h> |
19 | #include <unwind.h> |
20 | |
21 | struct unw_eh_callback_data |
22 | { |
23 | _Unwind_Ptr pc; |
24 | _Unwind_Ptr exidx_start; |
25 | int exidx_len; |
26 | }; |
27 | |
28 | |
29 | /* Callback to determins if the PC lies within an object, and remember the |
30 | location of the exception index table if it does. */ |
31 | |
32 | static int |
33 | find_exidx_callback (struct dl_phdr_info * info, size_t size, void * ptr) |
34 | { |
35 | struct unw_eh_callback_data * data; |
36 | const ElfW(Phdr) *phdr; |
37 | int i; |
38 | int match; |
39 | _Unwind_Ptr load_base; |
40 | |
41 | data = (struct unw_eh_callback_data *) ptr; |
42 | load_base = info->dlpi_addr; |
43 | phdr = info->dlpi_phdr; |
44 | |
45 | match = 0; |
46 | for (i = info->dlpi_phnum; i > 0; i--, phdr++) |
47 | { |
48 | if (phdr->p_type == PT_LOAD) |
49 | { |
50 | _Unwind_Ptr vaddr = phdr->p_vaddr + load_base; |
51 | if (data->pc >= vaddr && data->pc < vaddr + phdr->p_memsz) |
52 | match = 1; |
53 | } |
54 | else if (phdr->p_type == PT_ARM_EXIDX) |
55 | { |
56 | data->exidx_start = (_Unwind_Ptr) (phdr->p_vaddr + load_base); |
57 | data->exidx_len = phdr->p_memsz; |
58 | } |
59 | } |
60 | |
61 | return match; |
62 | } |
63 | |
64 | |
65 | /* Find the exception index table containing PC. */ |
66 | |
67 | _Unwind_Ptr |
68 | __gnu_Unwind_Find_exidx (_Unwind_Ptr pc, int * pcount) |
69 | { |
70 | struct unw_eh_callback_data data; |
71 | |
72 | data.pc = pc; |
73 | data.exidx_start = 0; |
74 | if (__dl_iterate_phdr (find_exidx_callback, &data) <= 0) |
75 | return 0; |
76 | |
77 | *pcount = data.exidx_len / 8; |
78 | return data.exidx_start; |
79 | } |
80 | |