| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame] | 1 | /* Communicate dynamic linker state to the debugger at runtime. |
| 2 | Copyright (C) 1996-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <ldsodefs.h> |
| 20 | |
| 21 | |
| 22 | /* These are the members in the public `struct link_map' type. |
| 23 | Sanity check that the internal type and the public type match. */ |
| 24 | #define VERIFY_MEMBER(name) \ |
| 25 | (offsetof (struct link_map_public, name) == offsetof (struct link_map, name)) |
| 26 | extern const int verify_link_map_members[(VERIFY_MEMBER (l_addr) |
| 27 | && VERIFY_MEMBER (l_name) |
| 28 | && VERIFY_MEMBER (l_ld) |
| 29 | && VERIFY_MEMBER (l_next) |
| 30 | && VERIFY_MEMBER (l_prev)) |
| 31 | ? 1 : -1]; |
| 32 | |
| 33 | /* This structure communicates dl state to the debugger. The debugger |
| 34 | normally finds it via the DT_DEBUG entry in the dynamic section, but in |
| 35 | a statically-linked program there is no dynamic section for the debugger |
| 36 | to examine and it looks for this particular symbol name. */ |
| 37 | struct r_debug _r_debug; |
| 38 | |
| 39 | |
| 40 | /* Initialize _r_debug if it has not already been done. The argument is |
| 41 | the run-time load address of the dynamic linker, to be put in |
| 42 | _r_debug.r_ldbase. Returns the address of _r_debug. */ |
| 43 | |
| 44 | struct r_debug * |
| 45 | internal_function |
| 46 | _dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns) |
| 47 | { |
| 48 | struct r_debug *r; |
| 49 | |
| 50 | if (ns == LM_ID_BASE) |
| 51 | r = &_r_debug; |
| 52 | else |
| 53 | r = &GL(dl_ns)[ns]._ns_debug; |
| 54 | |
| 55 | if (r->r_map == NULL || ldbase != 0) |
| 56 | { |
| 57 | /* Tell the debugger where to find the map of loaded objects. */ |
| 58 | r->r_version = 1 /* R_DEBUG_VERSION XXX */; |
| 59 | r->r_ldbase = ldbase ?: _r_debug.r_ldbase; |
| 60 | r->r_map = (void *) GL(dl_ns)[ns]._ns_loaded; |
| 61 | r->r_brk = (ElfW(Addr)) &_dl_debug_state; |
| 62 | } |
| 63 | |
| 64 | return r; |
| 65 | } |
| 66 | |
| 67 | |
| 68 | /* This function exists solely to have a breakpoint set on it by the |
| 69 | debugger. The debugger is supposed to find this function's address by |
| 70 | examining the r_brk member of struct r_debug, but GDB 4.15 in fact looks |
| 71 | for this particular symbol name in the PT_INTERP file. */ |
| 72 | void |
| 73 | _dl_debug_state (void) |
| 74 | { |
| 75 | } |
| 76 | rtld_hidden_def (_dl_debug_state) |