binutils-gdb/gdb/solib-svr4.h
Markus Metzger 8d56636a0e gdb, gdbserver: support dlmopen()
In glibc, the r_debug structure contains (amongst others) the following
fields:

  int r_version:
    Version number for this protocol.  It should be greater than 0.

If r_version is 2, struct r_debug is extended to struct r_debug_extended
with one additional field:

  struct r_debug_extended *r_next;
    Link to the next r_debug_extended structure.  Each r_debug_extended
    structure represents a different namespace.  The first r_debug_extended
    structure is for the default namespace.

1. Change solib_svr4_r_map argument to take the debug base.
2. Add solib_svr4_r_next to find the link map in the next namespace from
the r_next field.
3. Update svr4_current_sos_direct to get the link map in the next namespace
from the r_next field.
4. Don't check shared libraries in other namespaces when updating shared
libraries in a new namespace.
5. Update svr4_same to check the load offset in addition to the name
6. Update svr4_default_sos to also set l_addr_inferior
7. Change the flat solib_list into a per-namespace list using the
namespace's r_debug address to identify the namespace.

Add gdb.base/dlmopen.exp to test this.

To remain backwards compatible with older gdbserver, we reserve the
namespace zero for a flat list of solibs from all namespaces.  Subsequent
patches will extend RSP to allow listing libraries grouped by namespace.

This fixes PR 11839.

Co-authored-by: Lu, Hongjiu  <hongjiu.lu@intel.com>
2022-10-18 14:16:08 +02:00

114 lines
3.7 KiB
C

/* Handle shared libraries for GDB, the GNU Debugger.
Copyright (C) 2000-2022 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef SOLIB_SVR4_H
#define SOLIB_SVR4_H
#include "solist.h"
struct objfile;
struct target_so_ops;
extern const struct target_so_ops svr4_so_ops;
/* Link map info to include in an allocated so_list entry. */
struct lm_info_svr4 : public lm_info_base
{
/* Amount by which addresses in the binary should be relocated to
match the inferior. The direct inferior value is L_ADDR_INFERIOR.
When prelinking is involved and the prelink base address changes,
we may need a different offset - the recomputed offset is in L_ADDR.
It is commonly the same value. It is cached as we want to warn about
the difference and compute it only once. L_ADDR is valid
iff L_ADDR_P. */
CORE_ADDR l_addr = 0, l_addr_inferior = 0;
bool l_addr_p = false;
/* The target location of lm. */
CORE_ADDR lm_addr = 0;
/* Values read in from inferior's fields of the same name. */
CORE_ADDR l_ld = 0, l_next = 0, l_prev = 0, l_name = 0;
};
/* Critical offsets and sizes which describe struct r_debug and
struct link_map on SVR4-like targets. All offsets and sizes are
in bytes unless otherwise specified. */
struct link_map_offsets
{
/* Offset and size of r_debug.r_version. */
int r_version_offset, r_version_size;
/* Offset of r_debug.r_map. */
int r_map_offset;
/* Offset of r_debug.r_brk. */
int r_brk_offset;
/* Offset of r_debug.r_ldsomap. */
int r_ldsomap_offset;
/* Offset of r_debug_extended.r_next. */
int r_next_offset;
/* Size of struct link_map (or equivalent), or at least enough of it
to be able to obtain the fields below. */
int link_map_size;
/* Offset to l_addr field in struct link_map. */
int l_addr_offset;
/* Offset to l_ld field in struct link_map. */
int l_ld_offset;
/* Offset to l_next field in struct link_map. */
int l_next_offset;
/* Offset to l_prev field in struct link_map. */
int l_prev_offset;
/* Offset to l_name field in struct link_map. */
int l_name_offset;
};
/* set_solib_svr4_fetch_link_map_offsets() is intended to be called by
a <arch>_gdbarch_init() function. It is used to establish an
architecture specific link_map_offsets fetcher for the architecture
being defined. */
extern void set_solib_svr4_fetch_link_map_offsets
(struct gdbarch *gdbarch, struct link_map_offsets *(*func) (void));
/* This function is called by thread_db.c. Return the address of the
link map for the given objfile. */
extern CORE_ADDR svr4_fetch_objfile_link_map (struct objfile *objfile);
/* Fetch (and possibly build) an appropriate `struct link_map_offsets'
for ILP32 and LP64 SVR4 systems. */
extern struct link_map_offsets *svr4_ilp32_fetch_link_map_offsets (void);
extern struct link_map_offsets *svr4_lp64_fetch_link_map_offsets (void);
/* Return 1 if PC lies in the dynamic symbol resolution code of the
SVR4 run time loader. */
int svr4_in_dynsym_resolve_code (CORE_ADDR pc);
#endif /* solib-svr4.h */