diff options
Diffstat (limited to 'libc/elf/dl-debug.c')
| -rw-r--r-- | libc/elf/dl-debug.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/libc/elf/dl-debug.c b/libc/elf/dl-debug.c new file mode 100644 index 000000000..d00fe87fb --- /dev/null +++ b/libc/elf/dl-debug.c @@ -0,0 +1,78 @@ +/* Communicate dynamic linker state to the debugger at runtime. + Copyright (C) 1996, 1998,2000,2002,2004,2005,2006 + Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <ldsodefs.h> + + +/* These are the members in the public `struct link_map' type. + Sanity check that the internal type and the public type match. */ +#define VERIFY_MEMBER(name) \ + (offsetof (struct link_map_public, name) == offsetof (struct link_map, name)) +extern const int verify_link_map_members[(VERIFY_MEMBER (l_addr) + && VERIFY_MEMBER (l_name) + && VERIFY_MEMBER (l_ld) + && VERIFY_MEMBER (l_next) + && VERIFY_MEMBER (l_prev)) + ? 1 : -1]; + +/* This structure communicates dl state to the debugger. The debugger + normally finds it via the DT_DEBUG entry in the dynamic section, but in + a statically-linked program there is no dynamic section for the debugger + to examine and it looks for this particular symbol name. */ +struct r_debug _r_debug; + + +/* Initialize _r_debug if it has not already been done. The argument is + the run-time load address of the dynamic linker, to be put in + _r_debug.r_ldbase. Returns the address of _r_debug. */ + +struct r_debug * +internal_function +_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns) +{ + struct r_debug *r; + + if (ns == LM_ID_BASE) + r = &_r_debug; + else + r = &GL(dl_ns)[ns]._ns_debug; + + if (r->r_brk == 0 || ldbase != 0) + { + /* Tell the debugger where to find the map of loaded objects. */ + r->r_version = 1 /* R_DEBUG_VERSION XXX */; + r->r_ldbase = ldbase ?: _r_debug.r_ldbase; + r->r_map = (void *) GL(dl_ns)[ns]._ns_loaded; + r->r_brk = (ElfW(Addr)) &_dl_debug_state; + } + + return r; +} + + +/* This function exists solely to have a breakpoint set on it by the + debugger. The debugger is supposed to find this function's address by + examining the r_brk member of struct r_debug, but GDB 4.15 in fact looks + for this particular symbol name in the PT_INTERP file. */ +void +_dl_debug_state (void) +{ +} +rtld_hidden_def (_dl_debug_state) |