mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-21 04:42:53 +08:00
8e260fc026
* solib-svr4.c (_initialize_svr4_solib): Update * solib-dsbt.c (_initialize_dsbt_solib): Update. * solib-darwin.c (_initialize_darwin_solib): Update. * registry.h: New file. * python/py-progspace.c (gdbpy_initialize_pspace): Update. * python/py-inferior.c (gdbpy_initialize_inferior): Update. * progspace.h: Include registry.h. Use DECLARE_REGISTRY. (register_program_space_data_with_cleanup) (register_program_space_data, program_space_alloc_data) (clear_program_space_data, set_program_space_data) (program_space_data): Don't declare. * progspace.c: Use DEFINE_REGISTRY. (struct program_space_data, struct program_space_data_registration, struct program_space_data_registry, program_space_data_registry) (register_program_space_data_with_cleanup) (register_program_space_data, program_space_alloc_data) (program_space_free_data, clear_program_space_data) (set_program_space_data, program_space_data): Remove. * objfiles.h: Include registry.h. Use DECLARE_REGISTRY. (struct objfile) <data, num_data>: Replace with REGISTRY_FIELDS. (register_objfile_data_with_cleanup, register_objfile_data) (clear_objfile_data, set_objfile_data, objfile_data): Don't declare. * objfiles.c: Use DEFINE_REGISTRY. (struct objfile_data, struct objfile_data_registration, struct objfile_data_registry, objfile_data_registry) (register_objfile_data_with_cleanup, register_objfile_data) (objfile_alloc_data, objfile_free_data, clear_objfile_data) (set_objfile_data, objfile_data): Remove. (_initialize_objfiles): Update. * jit.c (_initialize_jit): Update. * inflow.c (_initialize_inflow): Update. * inferior.h: Include registry.h. Use DECLARE_REGISTRY. (struct inferior) <data, num_data>: Replace with REGISTRY_FIELDS. (register_inferior_data_with_cleanup, register_inferior_data) (clear_inferior_data, set_inferior_data, inferior_data): Don't declare. * inferior.c: Use DEFINE_REGISTRY. (struct inferior_data, struct inferior_data_registration, struct inferior_data_registry, inferior_data_registry) (register_inferior_data_with_cleanup, register_inferior_data) (inferior_alloc_data, inferior_free_data clear_inferior_data) (set_inferior_data, inferior_data): Remove. * auxv.c (_initialize_auxv): Update. * ada-lang.c (_initialize_ada_language): Update. * breakpoint.c (_initialize_breakpoint): Update. * i386-nat.c (i386_use_watchpoints): Update.
2502 lines
77 KiB
C
2502 lines
77 KiB
C
/* Handle SVR4 shared libraries for GDB, the GNU Debugger.
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Copyright (C) 1990-1996, 1998-2001, 2003-2012 Free Software
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Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
|
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "elf/external.h"
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#include "elf/common.h"
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#include "elf/mips.h"
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#include "symtab.h"
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#include "bfd.h"
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#include "symfile.h"
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#include "objfiles.h"
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#include "gdbcore.h"
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#include "target.h"
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#include "inferior.h"
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#include "regcache.h"
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#include "gdbthread.h"
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#include "observer.h"
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#include "gdb_assert.h"
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#include "solist.h"
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#include "solib.h"
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#include "solib-svr4.h"
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#include "bfd-target.h"
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#include "elf-bfd.h"
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#include "exec.h"
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#include "auxv.h"
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#include "exceptions.h"
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#include "gdb_bfd.h"
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static struct link_map_offsets *svr4_fetch_link_map_offsets (void);
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static int svr4_have_link_map_offsets (void);
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static void svr4_relocate_main_executable (void);
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/* Link map info to include in an allocated so_list entry. */
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struct lm_info
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{
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/* Amount by which addresses in the binary should be relocated to
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match the inferior. The direct inferior value is L_ADDR_INFERIOR.
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When prelinking is involved and the prelink base address changes,
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we may need a different offset - the recomputed offset is in L_ADDR.
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It is commonly the same value. It is cached as we want to warn about
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the difference and compute it only once. L_ADDR is valid
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iff L_ADDR_P. */
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CORE_ADDR l_addr, l_addr_inferior;
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unsigned int l_addr_p : 1;
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/* The target location of lm. */
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CORE_ADDR lm_addr;
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/* Values read in from inferior's fields of the same name. */
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CORE_ADDR l_ld, l_next, l_prev, l_name;
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};
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/* On SVR4 systems, a list of symbols in the dynamic linker where
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GDB can try to place a breakpoint to monitor shared library
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events.
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If none of these symbols are found, or other errors occur, then
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SVR4 systems will fall back to using a symbol as the "startup
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mapping complete" breakpoint address. */
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static const char * const solib_break_names[] =
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{
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"r_debug_state",
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"_r_debug_state",
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"_dl_debug_state",
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"rtld_db_dlactivity",
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"__dl_rtld_db_dlactivity",
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"_rtld_debug_state",
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NULL
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};
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static const char * const bkpt_names[] =
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{
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"_start",
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"__start",
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"main",
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NULL
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};
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static const char * const main_name_list[] =
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{
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"main_$main",
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NULL
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};
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/* Return non-zero if GDB_SO_NAME and INFERIOR_SO_NAME represent
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the same shared library. */
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static int
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svr4_same_1 (const char *gdb_so_name, const char *inferior_so_name)
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{
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if (strcmp (gdb_so_name, inferior_so_name) == 0)
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return 1;
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/* On Solaris, when starting inferior we think that dynamic linker is
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/usr/lib/ld.so.1, but later on, the table of loaded shared libraries
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contains /lib/ld.so.1. Sometimes one file is a link to another, but
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sometimes they have identical content, but are not linked to each
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other. We don't restrict this check for Solaris, but the chances
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of running into this situation elsewhere are very low. */
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if (strcmp (gdb_so_name, "/usr/lib/ld.so.1") == 0
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&& strcmp (inferior_so_name, "/lib/ld.so.1") == 0)
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return 1;
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/* Similarly, we observed the same issue with sparc64, but with
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different locations. */
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if (strcmp (gdb_so_name, "/usr/lib/sparcv9/ld.so.1") == 0
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&& strcmp (inferior_so_name, "/lib/sparcv9/ld.so.1") == 0)
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return 1;
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|
||
return 0;
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}
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static int
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svr4_same (struct so_list *gdb, struct so_list *inferior)
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{
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return (svr4_same_1 (gdb->so_original_name, inferior->so_original_name));
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}
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static struct lm_info *
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lm_info_read (CORE_ADDR lm_addr)
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{
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struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
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gdb_byte *lm;
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struct lm_info *lm_info;
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struct cleanup *back_to;
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lm = xmalloc (lmo->link_map_size);
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back_to = make_cleanup (xfree, lm);
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if (target_read_memory (lm_addr, lm, lmo->link_map_size) != 0)
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{
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warning (_("Error reading shared library list entry at %s"),
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paddress (target_gdbarch, lm_addr)),
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lm_info = NULL;
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}
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else
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{
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struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
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lm_info = xzalloc (sizeof (*lm_info));
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lm_info->lm_addr = lm_addr;
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lm_info->l_addr_inferior = extract_typed_address (&lm[lmo->l_addr_offset],
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ptr_type);
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lm_info->l_ld = extract_typed_address (&lm[lmo->l_ld_offset], ptr_type);
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lm_info->l_next = extract_typed_address (&lm[lmo->l_next_offset],
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ptr_type);
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lm_info->l_prev = extract_typed_address (&lm[lmo->l_prev_offset],
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ptr_type);
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lm_info->l_name = extract_typed_address (&lm[lmo->l_name_offset],
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ptr_type);
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}
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do_cleanups (back_to);
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return lm_info;
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}
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static int
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has_lm_dynamic_from_link_map (void)
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{
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struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
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return lmo->l_ld_offset >= 0;
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}
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static CORE_ADDR
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lm_addr_check (struct so_list *so, bfd *abfd)
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{
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if (!so->lm_info->l_addr_p)
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{
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struct bfd_section *dyninfo_sect;
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CORE_ADDR l_addr, l_dynaddr, dynaddr;
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l_addr = so->lm_info->l_addr_inferior;
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if (! abfd || ! has_lm_dynamic_from_link_map ())
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goto set_addr;
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l_dynaddr = so->lm_info->l_ld;
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dyninfo_sect = bfd_get_section_by_name (abfd, ".dynamic");
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if (dyninfo_sect == NULL)
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goto set_addr;
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dynaddr = bfd_section_vma (abfd, dyninfo_sect);
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if (dynaddr + l_addr != l_dynaddr)
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{
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CORE_ADDR align = 0x1000;
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CORE_ADDR minpagesize = align;
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if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
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{
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Elf_Internal_Ehdr *ehdr = elf_tdata (abfd)->elf_header;
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Elf_Internal_Phdr *phdr = elf_tdata (abfd)->phdr;
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int i;
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align = 1;
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for (i = 0; i < ehdr->e_phnum; i++)
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if (phdr[i].p_type == PT_LOAD && phdr[i].p_align > align)
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align = phdr[i].p_align;
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minpagesize = get_elf_backend_data (abfd)->minpagesize;
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}
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/* Turn it into a mask. */
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align--;
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/* If the changes match the alignment requirements, we
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assume we're using a core file that was generated by the
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same binary, just prelinked with a different base offset.
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If it doesn't match, we may have a different binary, the
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same binary with the dynamic table loaded at an unrelated
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location, or anything, really. To avoid regressions,
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don't adjust the base offset in the latter case, although
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odds are that, if things really changed, debugging won't
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quite work.
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One could expect more the condition
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((l_addr & align) == 0 && ((l_dynaddr - dynaddr) & align) == 0)
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but the one below is relaxed for PPC. The PPC kernel supports
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either 4k or 64k page sizes. To be prepared for 64k pages,
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PPC ELF files are built using an alignment requirement of 64k.
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However, when running on a kernel supporting 4k pages, the memory
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mapping of the library may not actually happen on a 64k boundary!
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(In the usual case where (l_addr & align) == 0, this check is
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equivalent to the possibly expected check above.)
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Even on PPC it must be zero-aligned at least for MINPAGESIZE. */
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l_addr = l_dynaddr - dynaddr;
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if ((l_addr & (minpagesize - 1)) == 0
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&& (l_addr & align) == ((l_dynaddr - dynaddr) & align))
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{
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if (info_verbose)
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printf_unfiltered (_("Using PIC (Position Independent Code) "
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"prelink displacement %s for \"%s\".\n"),
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paddress (target_gdbarch, l_addr),
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so->so_name);
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}
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else
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{
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/* There is no way to verify the library file matches. prelink
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can during prelinking of an unprelinked file (or unprelinking
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of a prelinked file) shift the DYNAMIC segment by arbitrary
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offset without any page size alignment. There is no way to
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find out the ELF header and/or Program Headers for a limited
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verification if it they match. One could do a verification
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of the DYNAMIC segment. Still the found address is the best
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one GDB could find. */
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warning (_(".dynamic section for \"%s\" "
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"is not at the expected address "
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"(wrong library or version mismatch?)"), so->so_name);
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}
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}
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set_addr:
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so->lm_info->l_addr = l_addr;
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so->lm_info->l_addr_p = 1;
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}
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return so->lm_info->l_addr;
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}
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/* Per pspace SVR4 specific data. */
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struct svr4_info
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{
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CORE_ADDR debug_base; /* Base of dynamic linker structures. */
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/* Validity flag for debug_loader_offset. */
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int debug_loader_offset_p;
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/* Load address for the dynamic linker, inferred. */
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CORE_ADDR debug_loader_offset;
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/* Name of the dynamic linker, valid if debug_loader_offset_p. */
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char *debug_loader_name;
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/* Load map address for the main executable. */
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CORE_ADDR main_lm_addr;
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CORE_ADDR interp_text_sect_low;
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CORE_ADDR interp_text_sect_high;
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CORE_ADDR interp_plt_sect_low;
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CORE_ADDR interp_plt_sect_high;
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};
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/* Per-program-space data key. */
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static const struct program_space_data *solib_svr4_pspace_data;
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static void
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svr4_pspace_data_cleanup (struct program_space *pspace, void *arg)
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{
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struct svr4_info *info;
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info = program_space_data (pspace, solib_svr4_pspace_data);
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xfree (info);
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}
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/* Get the current svr4 data. If none is found yet, add it now. This
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function always returns a valid object. */
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static struct svr4_info *
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get_svr4_info (void)
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{
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struct svr4_info *info;
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info = program_space_data (current_program_space, solib_svr4_pspace_data);
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if (info != NULL)
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return info;
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info = XZALLOC (struct svr4_info);
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set_program_space_data (current_program_space, solib_svr4_pspace_data, info);
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return info;
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}
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/* Local function prototypes */
|
||
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static int match_main (const char *);
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/* Read program header TYPE from inferior memory. The header is found
|
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by scanning the OS auxillary vector.
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|
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If TYPE == -1, return the program headers instead of the contents of
|
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one program header.
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Return a pointer to allocated memory holding the program header contents,
|
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or NULL on failure. If sucessful, and unless P_SECT_SIZE is NULL, the
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size of those contents is returned to P_SECT_SIZE. Likewise, the target
|
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architecture size (32-bit or 64-bit) is returned to P_ARCH_SIZE. */
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static gdb_byte *
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read_program_header (int type, int *p_sect_size, int *p_arch_size)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
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CORE_ADDR at_phdr, at_phent, at_phnum, pt_phdr = 0;
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int arch_size, sect_size;
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||
CORE_ADDR sect_addr;
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gdb_byte *buf;
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int pt_phdr_p = 0;
|
||
|
||
/* Get required auxv elements from target. */
|
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if (target_auxv_search (¤t_target, AT_PHDR, &at_phdr) <= 0)
|
||
return 0;
|
||
if (target_auxv_search (¤t_target, AT_PHENT, &at_phent) <= 0)
|
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return 0;
|
||
if (target_auxv_search (¤t_target, AT_PHNUM, &at_phnum) <= 0)
|
||
return 0;
|
||
if (!at_phdr || !at_phnum)
|
||
return 0;
|
||
|
||
/* Determine ELF architecture type. */
|
||
if (at_phent == sizeof (Elf32_External_Phdr))
|
||
arch_size = 32;
|
||
else if (at_phent == sizeof (Elf64_External_Phdr))
|
||
arch_size = 64;
|
||
else
|
||
return 0;
|
||
|
||
/* Find the requested segment. */
|
||
if (type == -1)
|
||
{
|
||
sect_addr = at_phdr;
|
||
sect_size = at_phent * at_phnum;
|
||
}
|
||
else if (arch_size == 32)
|
||
{
|
||
Elf32_External_Phdr phdr;
|
||
int i;
|
||
|
||
/* Search for requested PHDR. */
|
||
for (i = 0; i < at_phnum; i++)
|
||
{
|
||
int p_type;
|
||
|
||
if (target_read_memory (at_phdr + i * sizeof (phdr),
|
||
(gdb_byte *)&phdr, sizeof (phdr)))
|
||
return 0;
|
||
|
||
p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type,
|
||
4, byte_order);
|
||
|
||
if (p_type == PT_PHDR)
|
||
{
|
||
pt_phdr_p = 1;
|
||
pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr,
|
||
4, byte_order);
|
||
}
|
||
|
||
if (p_type == type)
|
||
break;
|
||
}
|
||
|
||
if (i == at_phnum)
|
||
return 0;
|
||
|
||
/* Retrieve address and size. */
|
||
sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr,
|
||
4, byte_order);
|
||
sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz,
|
||
4, byte_order);
|
||
}
|
||
else
|
||
{
|
||
Elf64_External_Phdr phdr;
|
||
int i;
|
||
|
||
/* Search for requested PHDR. */
|
||
for (i = 0; i < at_phnum; i++)
|
||
{
|
||
int p_type;
|
||
|
||
if (target_read_memory (at_phdr + i * sizeof (phdr),
|
||
(gdb_byte *)&phdr, sizeof (phdr)))
|
||
return 0;
|
||
|
||
p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type,
|
||
4, byte_order);
|
||
|
||
if (p_type == PT_PHDR)
|
||
{
|
||
pt_phdr_p = 1;
|
||
pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr,
|
||
8, byte_order);
|
||
}
|
||
|
||
if (p_type == type)
|
||
break;
|
||
}
|
||
|
||
if (i == at_phnum)
|
||
return 0;
|
||
|
||
/* Retrieve address and size. */
|
||
sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr,
|
||
8, byte_order);
|
||
sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz,
|
||
8, byte_order);
|
||
}
|
||
|
||
/* PT_PHDR is optional, but we really need it
|
||
for PIE to make this work in general. */
|
||
|
||
if (pt_phdr_p)
|
||
{
|
||
/* at_phdr is real address in memory. pt_phdr is what pheader says it is.
|
||
Relocation offset is the difference between the two. */
|
||
sect_addr = sect_addr + (at_phdr - pt_phdr);
|
||
}
|
||
|
||
/* Read in requested program header. */
|
||
buf = xmalloc (sect_size);
|
||
if (target_read_memory (sect_addr, buf, sect_size))
|
||
{
|
||
xfree (buf);
|
||
return NULL;
|
||
}
|
||
|
||
if (p_arch_size)
|
||
*p_arch_size = arch_size;
|
||
if (p_sect_size)
|
||
*p_sect_size = sect_size;
|
||
|
||
return buf;
|
||
}
|
||
|
||
|
||
/* Return program interpreter string. */
|
||
static gdb_byte *
|
||
find_program_interpreter (void)
|
||
{
|
||
gdb_byte *buf = NULL;
|
||
|
||
/* If we have an exec_bfd, use its section table. */
|
||
if (exec_bfd
|
||
&& bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour)
|
||
{
|
||
struct bfd_section *interp_sect;
|
||
|
||
interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
|
||
if (interp_sect != NULL)
|
||
{
|
||
int sect_size = bfd_section_size (exec_bfd, interp_sect);
|
||
|
||
buf = xmalloc (sect_size);
|
||
bfd_get_section_contents (exec_bfd, interp_sect, buf, 0, sect_size);
|
||
}
|
||
}
|
||
|
||
/* If we didn't find it, use the target auxillary vector. */
|
||
if (!buf)
|
||
buf = read_program_header (PT_INTERP, NULL, NULL);
|
||
|
||
return buf;
|
||
}
|
||
|
||
|
||
/* Scan for DYNTAG in .dynamic section of ABFD. If DYNTAG is found 1 is
|
||
returned and the corresponding PTR is set. */
|
||
|
||
static int
|
||
scan_dyntag (int dyntag, bfd *abfd, CORE_ADDR *ptr)
|
||
{
|
||
int arch_size, step, sect_size;
|
||
long dyn_tag;
|
||
CORE_ADDR dyn_ptr, dyn_addr;
|
||
gdb_byte *bufend, *bufstart, *buf;
|
||
Elf32_External_Dyn *x_dynp_32;
|
||
Elf64_External_Dyn *x_dynp_64;
|
||
struct bfd_section *sect;
|
||
struct target_section *target_section;
|
||
|
||
if (abfd == NULL)
|
||
return 0;
|
||
|
||
if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
|
||
return 0;
|
||
|
||
arch_size = bfd_get_arch_size (abfd);
|
||
if (arch_size == -1)
|
||
return 0;
|
||
|
||
/* Find the start address of the .dynamic section. */
|
||
sect = bfd_get_section_by_name (abfd, ".dynamic");
|
||
if (sect == NULL)
|
||
return 0;
|
||
|
||
for (target_section = current_target_sections->sections;
|
||
target_section < current_target_sections->sections_end;
|
||
target_section++)
|
||
if (sect == target_section->the_bfd_section)
|
||
break;
|
||
if (target_section < current_target_sections->sections_end)
|
||
dyn_addr = target_section->addr;
|
||
else
|
||
{
|
||
/* ABFD may come from OBJFILE acting only as a symbol file without being
|
||
loaded into the target (see add_symbol_file_command). This case is
|
||
such fallback to the file VMA address without the possibility of
|
||
having the section relocated to its actual in-memory address. */
|
||
|
||
dyn_addr = bfd_section_vma (abfd, sect);
|
||
}
|
||
|
||
/* Read in .dynamic from the BFD. We will get the actual value
|
||
from memory later. */
|
||
sect_size = bfd_section_size (abfd, sect);
|
||
buf = bufstart = alloca (sect_size);
|
||
if (!bfd_get_section_contents (abfd, sect,
|
||
buf, 0, sect_size))
|
||
return 0;
|
||
|
||
/* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */
|
||
step = (arch_size == 32) ? sizeof (Elf32_External_Dyn)
|
||
: sizeof (Elf64_External_Dyn);
|
||
for (bufend = buf + sect_size;
|
||
buf < bufend;
|
||
buf += step)
|
||
{
|
||
if (arch_size == 32)
|
||
{
|
||
x_dynp_32 = (Elf32_External_Dyn *) buf;
|
||
dyn_tag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_tag);
|
||
dyn_ptr = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_un.d_ptr);
|
||
}
|
||
else
|
||
{
|
||
x_dynp_64 = (Elf64_External_Dyn *) buf;
|
||
dyn_tag = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_tag);
|
||
dyn_ptr = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_un.d_ptr);
|
||
}
|
||
if (dyn_tag == DT_NULL)
|
||
return 0;
|
||
if (dyn_tag == dyntag)
|
||
{
|
||
/* If requested, try to read the runtime value of this .dynamic
|
||
entry. */
|
||
if (ptr)
|
||
{
|
||
struct type *ptr_type;
|
||
gdb_byte ptr_buf[8];
|
||
CORE_ADDR ptr_addr;
|
||
|
||
ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
ptr_addr = dyn_addr + (buf - bufstart) + arch_size / 8;
|
||
if (target_read_memory (ptr_addr, ptr_buf, arch_size / 8) == 0)
|
||
dyn_ptr = extract_typed_address (ptr_buf, ptr_type);
|
||
*ptr = dyn_ptr;
|
||
}
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Scan for DYNTAG in .dynamic section of the target's main executable,
|
||
found by consulting the OS auxillary vector. If DYNTAG is found 1 is
|
||
returned and the corresponding PTR is set. */
|
||
|
||
static int
|
||
scan_dyntag_auxv (int dyntag, CORE_ADDR *ptr)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
|
||
int sect_size, arch_size, step;
|
||
long dyn_tag;
|
||
CORE_ADDR dyn_ptr;
|
||
gdb_byte *bufend, *bufstart, *buf;
|
||
|
||
/* Read in .dynamic section. */
|
||
buf = bufstart = read_program_header (PT_DYNAMIC, §_size, &arch_size);
|
||
if (!buf)
|
||
return 0;
|
||
|
||
/* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */
|
||
step = (arch_size == 32) ? sizeof (Elf32_External_Dyn)
|
||
: sizeof (Elf64_External_Dyn);
|
||
for (bufend = buf + sect_size;
|
||
buf < bufend;
|
||
buf += step)
|
||
{
|
||
if (arch_size == 32)
|
||
{
|
||
Elf32_External_Dyn *dynp = (Elf32_External_Dyn *) buf;
|
||
|
||
dyn_tag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag,
|
||
4, byte_order);
|
||
dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr,
|
||
4, byte_order);
|
||
}
|
||
else
|
||
{
|
||
Elf64_External_Dyn *dynp = (Elf64_External_Dyn *) buf;
|
||
|
||
dyn_tag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag,
|
||
8, byte_order);
|
||
dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr,
|
||
8, byte_order);
|
||
}
|
||
if (dyn_tag == DT_NULL)
|
||
break;
|
||
|
||
if (dyn_tag == dyntag)
|
||
{
|
||
if (ptr)
|
||
*ptr = dyn_ptr;
|
||
|
||
xfree (bufstart);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
xfree (bufstart);
|
||
return 0;
|
||
}
|
||
|
||
/* Locate the base address of dynamic linker structs for SVR4 elf
|
||
targets.
|
||
|
||
For SVR4 elf targets the address of the dynamic linker's runtime
|
||
structure is contained within the dynamic info section in the
|
||
executable file. The dynamic section is also mapped into the
|
||
inferior address space. Because the runtime loader fills in the
|
||
real address before starting the inferior, we have to read in the
|
||
dynamic info section from the inferior address space.
|
||
If there are any errors while trying to find the address, we
|
||
silently return 0, otherwise the found address is returned. */
|
||
|
||
static CORE_ADDR
|
||
elf_locate_base (void)
|
||
{
|
||
struct minimal_symbol *msymbol;
|
||
CORE_ADDR dyn_ptr;
|
||
|
||
/* Look for DT_MIPS_RLD_MAP first. MIPS executables use this
|
||
instead of DT_DEBUG, although they sometimes contain an unused
|
||
DT_DEBUG. */
|
||
if (scan_dyntag (DT_MIPS_RLD_MAP, exec_bfd, &dyn_ptr)
|
||
|| scan_dyntag_auxv (DT_MIPS_RLD_MAP, &dyn_ptr))
|
||
{
|
||
struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
gdb_byte *pbuf;
|
||
int pbuf_size = TYPE_LENGTH (ptr_type);
|
||
|
||
pbuf = alloca (pbuf_size);
|
||
/* DT_MIPS_RLD_MAP contains a pointer to the address
|
||
of the dynamic link structure. */
|
||
if (target_read_memory (dyn_ptr, pbuf, pbuf_size))
|
||
return 0;
|
||
return extract_typed_address (pbuf, ptr_type);
|
||
}
|
||
|
||
/* Find DT_DEBUG. */
|
||
if (scan_dyntag (DT_DEBUG, exec_bfd, &dyn_ptr)
|
||
|| scan_dyntag_auxv (DT_DEBUG, &dyn_ptr))
|
||
return dyn_ptr;
|
||
|
||
/* This may be a static executable. Look for the symbol
|
||
conventionally named _r_debug, as a last resort. */
|
||
msymbol = lookup_minimal_symbol ("_r_debug", NULL, symfile_objfile);
|
||
if (msymbol != NULL)
|
||
return SYMBOL_VALUE_ADDRESS (msymbol);
|
||
|
||
/* DT_DEBUG entry not found. */
|
||
return 0;
|
||
}
|
||
|
||
/* Locate the base address of dynamic linker structs.
|
||
|
||
For both the SunOS and SVR4 shared library implementations, if the
|
||
inferior executable has been linked dynamically, there is a single
|
||
address somewhere in the inferior's data space which is the key to
|
||
locating all of the dynamic linker's runtime structures. This
|
||
address is the value of the debug base symbol. The job of this
|
||
function is to find and return that address, or to return 0 if there
|
||
is no such address (the executable is statically linked for example).
|
||
|
||
For SunOS, the job is almost trivial, since the dynamic linker and
|
||
all of it's structures are statically linked to the executable at
|
||
link time. Thus the symbol for the address we are looking for has
|
||
already been added to the minimal symbol table for the executable's
|
||
objfile at the time the symbol file's symbols were read, and all we
|
||
have to do is look it up there. Note that we explicitly do NOT want
|
||
to find the copies in the shared library.
|
||
|
||
The SVR4 version is a bit more complicated because the address
|
||
is contained somewhere in the dynamic info section. We have to go
|
||
to a lot more work to discover the address of the debug base symbol.
|
||
Because of this complexity, we cache the value we find and return that
|
||
value on subsequent invocations. Note there is no copy in the
|
||
executable symbol tables. */
|
||
|
||
static CORE_ADDR
|
||
locate_base (struct svr4_info *info)
|
||
{
|
||
/* Check to see if we have a currently valid address, and if so, avoid
|
||
doing all this work again and just return the cached address. If
|
||
we have no cached address, try to locate it in the dynamic info
|
||
section for ELF executables. There's no point in doing any of this
|
||
though if we don't have some link map offsets to work with. */
|
||
|
||
if (info->debug_base == 0 && svr4_have_link_map_offsets ())
|
||
info->debug_base = elf_locate_base ();
|
||
return info->debug_base;
|
||
}
|
||
|
||
/* Find the first element in the inferior's dynamic link map, and
|
||
return its address in the inferior. Return zero if the address
|
||
could not be determined.
|
||
|
||
FIXME: Perhaps we should validate the info somehow, perhaps by
|
||
checking r_version for a known version number, or r_state for
|
||
RT_CONSISTENT. */
|
||
|
||
static CORE_ADDR
|
||
solib_svr4_r_map (struct svr4_info *info)
|
||
{
|
||
struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
|
||
struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
CORE_ADDR addr = 0;
|
||
volatile struct gdb_exception ex;
|
||
|
||
TRY_CATCH (ex, RETURN_MASK_ERROR)
|
||
{
|
||
addr = read_memory_typed_address (info->debug_base + lmo->r_map_offset,
|
||
ptr_type);
|
||
}
|
||
exception_print (gdb_stderr, ex);
|
||
return addr;
|
||
}
|
||
|
||
/* Find r_brk from the inferior's debug base. */
|
||
|
||
static CORE_ADDR
|
||
solib_svr4_r_brk (struct svr4_info *info)
|
||
{
|
||
struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
|
||
struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
|
||
return read_memory_typed_address (info->debug_base + lmo->r_brk_offset,
|
||
ptr_type);
|
||
}
|
||
|
||
/* Find the link map for the dynamic linker (if it is not in the
|
||
normal list of loaded shared objects). */
|
||
|
||
static CORE_ADDR
|
||
solib_svr4_r_ldsomap (struct svr4_info *info)
|
||
{
|
||
struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
|
||
struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
|
||
ULONGEST version;
|
||
|
||
/* Check version, and return zero if `struct r_debug' doesn't have
|
||
the r_ldsomap member. */
|
||
version
|
||
= read_memory_unsigned_integer (info->debug_base + lmo->r_version_offset,
|
||
lmo->r_version_size, byte_order);
|
||
if (version < 2 || lmo->r_ldsomap_offset == -1)
|
||
return 0;
|
||
|
||
return read_memory_typed_address (info->debug_base + lmo->r_ldsomap_offset,
|
||
ptr_type);
|
||
}
|
||
|
||
/* On Solaris systems with some versions of the dynamic linker,
|
||
ld.so's l_name pointer points to the SONAME in the string table
|
||
rather than into writable memory. So that GDB can find shared
|
||
libraries when loading a core file generated by gcore, ensure that
|
||
memory areas containing the l_name string are saved in the core
|
||
file. */
|
||
|
||
static int
|
||
svr4_keep_data_in_core (CORE_ADDR vaddr, unsigned long size)
|
||
{
|
||
struct svr4_info *info;
|
||
CORE_ADDR ldsomap;
|
||
struct so_list *new;
|
||
struct cleanup *old_chain;
|
||
struct link_map_offsets *lmo;
|
||
CORE_ADDR name_lm;
|
||
|
||
info = get_svr4_info ();
|
||
|
||
info->debug_base = 0;
|
||
locate_base (info);
|
||
if (!info->debug_base)
|
||
return 0;
|
||
|
||
ldsomap = solib_svr4_r_ldsomap (info);
|
||
if (!ldsomap)
|
||
return 0;
|
||
|
||
lmo = svr4_fetch_link_map_offsets ();
|
||
new = XZALLOC (struct so_list);
|
||
old_chain = make_cleanup (xfree, new);
|
||
new->lm_info = lm_info_read (ldsomap);
|
||
make_cleanup (xfree, new->lm_info);
|
||
name_lm = new->lm_info ? new->lm_info->l_name : 0;
|
||
do_cleanups (old_chain);
|
||
|
||
return (name_lm >= vaddr && name_lm < vaddr + size);
|
||
}
|
||
|
||
/* Implement the "open_symbol_file_object" target_so_ops method.
|
||
|
||
If no open symbol file, attempt to locate and open the main symbol
|
||
file. On SVR4 systems, this is the first link map entry. If its
|
||
name is here, we can open it. Useful when attaching to a process
|
||
without first loading its symbol file. */
|
||
|
||
static int
|
||
open_symbol_file_object (void *from_ttyp)
|
||
{
|
||
CORE_ADDR lm, l_name;
|
||
char *filename;
|
||
int errcode;
|
||
int from_tty = *(int *)from_ttyp;
|
||
struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
|
||
struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
|
||
int l_name_size = TYPE_LENGTH (ptr_type);
|
||
gdb_byte *l_name_buf = xmalloc (l_name_size);
|
||
struct cleanup *cleanups = make_cleanup (xfree, l_name_buf);
|
||
struct svr4_info *info = get_svr4_info ();
|
||
|
||
if (symfile_objfile)
|
||
if (!query (_("Attempt to reload symbols from process? ")))
|
||
{
|
||
do_cleanups (cleanups);
|
||
return 0;
|
||
}
|
||
|
||
/* Always locate the debug struct, in case it has moved. */
|
||
info->debug_base = 0;
|
||
if (locate_base (info) == 0)
|
||
{
|
||
do_cleanups (cleanups);
|
||
return 0; /* failed somehow... */
|
||
}
|
||
|
||
/* First link map member should be the executable. */
|
||
lm = solib_svr4_r_map (info);
|
||
if (lm == 0)
|
||
{
|
||
do_cleanups (cleanups);
|
||
return 0; /* failed somehow... */
|
||
}
|
||
|
||
/* Read address of name from target memory to GDB. */
|
||
read_memory (lm + lmo->l_name_offset, l_name_buf, l_name_size);
|
||
|
||
/* Convert the address to host format. */
|
||
l_name = extract_typed_address (l_name_buf, ptr_type);
|
||
|
||
if (l_name == 0)
|
||
{
|
||
do_cleanups (cleanups);
|
||
return 0; /* No filename. */
|
||
}
|
||
|
||
/* Now fetch the filename from target memory. */
|
||
target_read_string (l_name, &filename, SO_NAME_MAX_PATH_SIZE - 1, &errcode);
|
||
make_cleanup (xfree, filename);
|
||
|
||
if (errcode)
|
||
{
|
||
warning (_("failed to read exec filename from attached file: %s"),
|
||
safe_strerror (errcode));
|
||
do_cleanups (cleanups);
|
||
return 0;
|
||
}
|
||
|
||
/* Have a pathname: read the symbol file. */
|
||
symbol_file_add_main (filename, from_tty);
|
||
|
||
do_cleanups (cleanups);
|
||
return 1;
|
||
}
|
||
|
||
/* Data exchange structure for the XML parser as returned by
|
||
svr4_current_sos_via_xfer_libraries. */
|
||
|
||
struct svr4_library_list
|
||
{
|
||
struct so_list *head, **tailp;
|
||
|
||
/* Inferior address of struct link_map used for the main executable. It is
|
||
NULL if not known. */
|
||
CORE_ADDR main_lm;
|
||
};
|
||
|
||
/* Implementation for target_so_ops.free_so. */
|
||
|
||
static void
|
||
svr4_free_so (struct so_list *so)
|
||
{
|
||
xfree (so->lm_info);
|
||
}
|
||
|
||
/* Free so_list built so far (called via cleanup). */
|
||
|
||
static void
|
||
svr4_free_library_list (void *p_list)
|
||
{
|
||
struct so_list *list = *(struct so_list **) p_list;
|
||
|
||
while (list != NULL)
|
||
{
|
||
struct so_list *next = list->next;
|
||
|
||
free_so (list);
|
||
list = next;
|
||
}
|
||
}
|
||
|
||
#ifdef HAVE_LIBEXPAT
|
||
|
||
#include "xml-support.h"
|
||
|
||
/* Handle the start of a <library> element. Note: new elements are added
|
||
at the tail of the list, keeping the list in order. */
|
||
|
||
static void
|
||
library_list_start_library (struct gdb_xml_parser *parser,
|
||
const struct gdb_xml_element *element,
|
||
void *user_data, VEC(gdb_xml_value_s) *attributes)
|
||
{
|
||
struct svr4_library_list *list = user_data;
|
||
const char *name = xml_find_attribute (attributes, "name")->value;
|
||
ULONGEST *lmp = xml_find_attribute (attributes, "lm")->value;
|
||
ULONGEST *l_addrp = xml_find_attribute (attributes, "l_addr")->value;
|
||
ULONGEST *l_ldp = xml_find_attribute (attributes, "l_ld")->value;
|
||
struct so_list *new_elem;
|
||
|
||
new_elem = XZALLOC (struct so_list);
|
||
new_elem->lm_info = XZALLOC (struct lm_info);
|
||
new_elem->lm_info->lm_addr = *lmp;
|
||
new_elem->lm_info->l_addr_inferior = *l_addrp;
|
||
new_elem->lm_info->l_ld = *l_ldp;
|
||
|
||
strncpy (new_elem->so_name, name, sizeof (new_elem->so_name) - 1);
|
||
new_elem->so_name[sizeof (new_elem->so_name) - 1] = 0;
|
||
strcpy (new_elem->so_original_name, new_elem->so_name);
|
||
|
||
*list->tailp = new_elem;
|
||
list->tailp = &new_elem->next;
|
||
}
|
||
|
||
/* Handle the start of a <library-list-svr4> element. */
|
||
|
||
static void
|
||
svr4_library_list_start_list (struct gdb_xml_parser *parser,
|
||
const struct gdb_xml_element *element,
|
||
void *user_data, VEC(gdb_xml_value_s) *attributes)
|
||
{
|
||
struct svr4_library_list *list = user_data;
|
||
const char *version = xml_find_attribute (attributes, "version")->value;
|
||
struct gdb_xml_value *main_lm = xml_find_attribute (attributes, "main-lm");
|
||
|
||
if (strcmp (version, "1.0") != 0)
|
||
gdb_xml_error (parser,
|
||
_("SVR4 Library list has unsupported version \"%s\""),
|
||
version);
|
||
|
||
if (main_lm)
|
||
list->main_lm = *(ULONGEST *) main_lm->value;
|
||
}
|
||
|
||
/* The allowed elements and attributes for an XML library list.
|
||
The root element is a <library-list>. */
|
||
|
||
static const struct gdb_xml_attribute svr4_library_attributes[] =
|
||
{
|
||
{ "name", GDB_XML_AF_NONE, NULL, NULL },
|
||
{ "lm", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
|
||
{ "l_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
|
||
{ "l_ld", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
|
||
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
|
||
};
|
||
|
||
static const struct gdb_xml_element svr4_library_list_children[] =
|
||
{
|
||
{
|
||
"library", svr4_library_attributes, NULL,
|
||
GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
|
||
library_list_start_library, NULL
|
||
},
|
||
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
|
||
};
|
||
|
||
static const struct gdb_xml_attribute svr4_library_list_attributes[] =
|
||
{
|
||
{ "version", GDB_XML_AF_NONE, NULL, NULL },
|
||
{ "main-lm", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL },
|
||
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
|
||
};
|
||
|
||
static const struct gdb_xml_element svr4_library_list_elements[] =
|
||
{
|
||
{ "library-list-svr4", svr4_library_list_attributes, svr4_library_list_children,
|
||
GDB_XML_EF_NONE, svr4_library_list_start_list, NULL },
|
||
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
|
||
};
|
||
|
||
/* Parse qXfer:libraries:read packet into *SO_LIST_RETURN. Return 1 if
|
||
|
||
Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such
|
||
case. Return 1 if *SO_LIST_RETURN contains the library list, it may be
|
||
empty, caller is responsible for freeing all its entries. */
|
||
|
||
static int
|
||
svr4_parse_libraries (const char *document, struct svr4_library_list *list)
|
||
{
|
||
struct cleanup *back_to = make_cleanup (svr4_free_library_list,
|
||
&list->head);
|
||
|
||
memset (list, 0, sizeof (*list));
|
||
list->tailp = &list->head;
|
||
if (gdb_xml_parse_quick (_("target library list"), "library-list.dtd",
|
||
svr4_library_list_elements, document, list) == 0)
|
||
{
|
||
/* Parsed successfully, keep the result. */
|
||
discard_cleanups (back_to);
|
||
return 1;
|
||
}
|
||
|
||
do_cleanups (back_to);
|
||
return 0;
|
||
}
|
||
|
||
/* Attempt to get so_list from target via qXfer:libraries:read packet.
|
||
|
||
Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such
|
||
case. Return 1 if *SO_LIST_RETURN contains the library list, it may be
|
||
empty, caller is responsible for freeing all its entries. */
|
||
|
||
static int
|
||
svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list)
|
||
{
|
||
char *svr4_library_document;
|
||
int result;
|
||
struct cleanup *back_to;
|
||
|
||
/* Fetch the list of shared libraries. */
|
||
svr4_library_document = target_read_stralloc (¤t_target,
|
||
TARGET_OBJECT_LIBRARIES_SVR4,
|
||
NULL);
|
||
if (svr4_library_document == NULL)
|
||
return 0;
|
||
|
||
back_to = make_cleanup (xfree, svr4_library_document);
|
||
result = svr4_parse_libraries (svr4_library_document, list);
|
||
do_cleanups (back_to);
|
||
|
||
return result;
|
||
}
|
||
|
||
#else
|
||
|
||
static int
|
||
svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list)
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
#endif
|
||
|
||
/* If no shared library information is available from the dynamic
|
||
linker, build a fallback list from other sources. */
|
||
|
||
static struct so_list *
|
||
svr4_default_sos (void)
|
||
{
|
||
struct svr4_info *info = get_svr4_info ();
|
||
struct so_list *new;
|
||
|
||
if (!info->debug_loader_offset_p)
|
||
return NULL;
|
||
|
||
new = XZALLOC (struct so_list);
|
||
|
||
new->lm_info = xzalloc (sizeof (struct lm_info));
|
||
|
||
/* Nothing will ever check the other fields if we set l_addr_p. */
|
||
new->lm_info->l_addr = info->debug_loader_offset;
|
||
new->lm_info->l_addr_p = 1;
|
||
|
||
strncpy (new->so_name, info->debug_loader_name, SO_NAME_MAX_PATH_SIZE - 1);
|
||
new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
|
||
strcpy (new->so_original_name, new->so_name);
|
||
|
||
return new;
|
||
}
|
||
|
||
/* Read the whole inferior libraries chain starting at address LM. Add the
|
||
entries to the tail referenced by LINK_PTR_PTR. Ignore the first entry if
|
||
IGNORE_FIRST and set global MAIN_LM_ADDR according to it. */
|
||
|
||
static void
|
||
svr4_read_so_list (CORE_ADDR lm, struct so_list ***link_ptr_ptr,
|
||
int ignore_first)
|
||
{
|
||
CORE_ADDR prev_lm = 0, next_lm;
|
||
|
||
for (; lm != 0; prev_lm = lm, lm = next_lm)
|
||
{
|
||
struct link_map_offsets *lmo = svr4_fetch_link_map_offsets ();
|
||
struct so_list *new;
|
||
struct cleanup *old_chain;
|
||
int errcode;
|
||
char *buffer;
|
||
|
||
new = XZALLOC (struct so_list);
|
||
old_chain = make_cleanup_free_so (new);
|
||
|
||
new->lm_info = lm_info_read (lm);
|
||
if (new->lm_info == NULL)
|
||
{
|
||
do_cleanups (old_chain);
|
||
break;
|
||
}
|
||
|
||
next_lm = new->lm_info->l_next;
|
||
|
||
if (new->lm_info->l_prev != prev_lm)
|
||
{
|
||
warning (_("Corrupted shared library list: %s != %s"),
|
||
paddress (target_gdbarch, prev_lm),
|
||
paddress (target_gdbarch, new->lm_info->l_prev));
|
||
do_cleanups (old_chain);
|
||
break;
|
||
}
|
||
|
||
/* For SVR4 versions, the first entry in the link map is for the
|
||
inferior executable, so we must ignore it. For some versions of
|
||
SVR4, it has no name. For others (Solaris 2.3 for example), it
|
||
does have a name, so we can no longer use a missing name to
|
||
decide when to ignore it. */
|
||
if (ignore_first && new->lm_info->l_prev == 0)
|
||
{
|
||
struct svr4_info *info = get_svr4_info ();
|
||
|
||
info->main_lm_addr = new->lm_info->lm_addr;
|
||
do_cleanups (old_chain);
|
||
continue;
|
||
}
|
||
|
||
/* Extract this shared object's name. */
|
||
target_read_string (new->lm_info->l_name, &buffer,
|
||
SO_NAME_MAX_PATH_SIZE - 1, &errcode);
|
||
if (errcode != 0)
|
||
{
|
||
warning (_("Can't read pathname for load map: %s."),
|
||
safe_strerror (errcode));
|
||
do_cleanups (old_chain);
|
||
continue;
|
||
}
|
||
|
||
strncpy (new->so_name, buffer, SO_NAME_MAX_PATH_SIZE - 1);
|
||
new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
|
||
strcpy (new->so_original_name, new->so_name);
|
||
xfree (buffer);
|
||
|
||
/* If this entry has no name, or its name matches the name
|
||
for the main executable, don't include it in the list. */
|
||
if (! new->so_name[0] || match_main (new->so_name))
|
||
{
|
||
do_cleanups (old_chain);
|
||
continue;
|
||
}
|
||
|
||
discard_cleanups (old_chain);
|
||
new->next = 0;
|
||
**link_ptr_ptr = new;
|
||
*link_ptr_ptr = &new->next;
|
||
}
|
||
}
|
||
|
||
/* Implement the "current_sos" target_so_ops method. */
|
||
|
||
static struct so_list *
|
||
svr4_current_sos (void)
|
||
{
|
||
CORE_ADDR lm;
|
||
struct so_list *head = NULL;
|
||
struct so_list **link_ptr = &head;
|
||
struct svr4_info *info;
|
||
struct cleanup *back_to;
|
||
int ignore_first;
|
||
struct svr4_library_list library_list;
|
||
|
||
/* Fall back to manual examination of the target if the packet is not
|
||
supported or gdbserver failed to find DT_DEBUG. gdb.server/solib-list.exp
|
||
tests a case where gdbserver cannot find the shared libraries list while
|
||
GDB itself is able to find it via SYMFILE_OBJFILE.
|
||
|
||
Unfortunately statically linked inferiors will also fall back through this
|
||
suboptimal code path. */
|
||
|
||
if (svr4_current_sos_via_xfer_libraries (&library_list))
|
||
{
|
||
if (library_list.main_lm)
|
||
{
|
||
info = get_svr4_info ();
|
||
info->main_lm_addr = library_list.main_lm;
|
||
}
|
||
|
||
return library_list.head ? library_list.head : svr4_default_sos ();
|
||
}
|
||
|
||
info = get_svr4_info ();
|
||
|
||
/* Always locate the debug struct, in case it has moved. */
|
||
info->debug_base = 0;
|
||
locate_base (info);
|
||
|
||
/* If we can't find the dynamic linker's base structure, this
|
||
must not be a dynamically linked executable. Hmm. */
|
||
if (! info->debug_base)
|
||
return svr4_default_sos ();
|
||
|
||
/* Assume that everything is a library if the dynamic loader was loaded
|
||
late by a static executable. */
|
||
if (exec_bfd && bfd_get_section_by_name (exec_bfd, ".dynamic") == NULL)
|
||
ignore_first = 0;
|
||
else
|
||
ignore_first = 1;
|
||
|
||
back_to = make_cleanup (svr4_free_library_list, &head);
|
||
|
||
/* Walk the inferior's link map list, and build our list of
|
||
`struct so_list' nodes. */
|
||
lm = solib_svr4_r_map (info);
|
||
if (lm)
|
||
svr4_read_so_list (lm, &link_ptr, ignore_first);
|
||
|
||
/* On Solaris, the dynamic linker is not in the normal list of
|
||
shared objects, so make sure we pick it up too. Having
|
||
symbol information for the dynamic linker is quite crucial
|
||
for skipping dynamic linker resolver code. */
|
||
lm = solib_svr4_r_ldsomap (info);
|
||
if (lm)
|
||
svr4_read_so_list (lm, &link_ptr, 0);
|
||
|
||
discard_cleanups (back_to);
|
||
|
||
if (head == NULL)
|
||
return svr4_default_sos ();
|
||
|
||
return head;
|
||
}
|
||
|
||
/* Get the address of the link_map for a given OBJFILE. */
|
||
|
||
CORE_ADDR
|
||
svr4_fetch_objfile_link_map (struct objfile *objfile)
|
||
{
|
||
struct so_list *so;
|
||
struct svr4_info *info = get_svr4_info ();
|
||
|
||
/* Cause svr4_current_sos() to be run if it hasn't been already. */
|
||
if (info->main_lm_addr == 0)
|
||
solib_add (NULL, 0, ¤t_target, auto_solib_add);
|
||
|
||
/* svr4_current_sos() will set main_lm_addr for the main executable. */
|
||
if (objfile == symfile_objfile)
|
||
return info->main_lm_addr;
|
||
|
||
/* The other link map addresses may be found by examining the list
|
||
of shared libraries. */
|
||
for (so = master_so_list (); so; so = so->next)
|
||
if (so->objfile == objfile)
|
||
return so->lm_info->lm_addr;
|
||
|
||
/* Not found! */
|
||
return 0;
|
||
}
|
||
|
||
/* On some systems, the only way to recognize the link map entry for
|
||
the main executable file is by looking at its name. Return
|
||
non-zero iff SONAME matches one of the known main executable names. */
|
||
|
||
static int
|
||
match_main (const char *soname)
|
||
{
|
||
const char * const *mainp;
|
||
|
||
for (mainp = main_name_list; *mainp != NULL; mainp++)
|
||
{
|
||
if (strcmp (soname, *mainp) == 0)
|
||
return (1);
|
||
}
|
||
|
||
return (0);
|
||
}
|
||
|
||
/* 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)
|
||
{
|
||
struct svr4_info *info = get_svr4_info ();
|
||
|
||
return ((pc >= info->interp_text_sect_low
|
||
&& pc < info->interp_text_sect_high)
|
||
|| (pc >= info->interp_plt_sect_low
|
||
&& pc < info->interp_plt_sect_high)
|
||
|| in_plt_section (pc, NULL)
|
||
|| in_gnu_ifunc_stub (pc));
|
||
}
|
||
|
||
/* Given an executable's ABFD and target, compute the entry-point
|
||
address. */
|
||
|
||
static CORE_ADDR
|
||
exec_entry_point (struct bfd *abfd, struct target_ops *targ)
|
||
{
|
||
/* KevinB wrote ... for most targets, the address returned by
|
||
bfd_get_start_address() is the entry point for the start
|
||
function. But, for some targets, bfd_get_start_address() returns
|
||
the address of a function descriptor from which the entry point
|
||
address may be extracted. This address is extracted by
|
||
gdbarch_convert_from_func_ptr_addr(). The method
|
||
gdbarch_convert_from_func_ptr_addr() is the merely the identify
|
||
function for targets which don't use function descriptors. */
|
||
return gdbarch_convert_from_func_ptr_addr (target_gdbarch,
|
||
bfd_get_start_address (abfd),
|
||
targ);
|
||
}
|
||
|
||
/* Helper function for gdb_bfd_lookup_symbol. */
|
||
|
||
static int
|
||
cmp_name_and_sec_flags (asymbol *sym, void *data)
|
||
{
|
||
return (strcmp (sym->name, (const char *) data) == 0
|
||
&& (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0);
|
||
}
|
||
/* Arrange for dynamic linker to hit breakpoint.
|
||
|
||
Both the SunOS and the SVR4 dynamic linkers have, as part of their
|
||
debugger interface, support for arranging for the inferior to hit
|
||
a breakpoint after mapping in the shared libraries. This function
|
||
enables that breakpoint.
|
||
|
||
For SunOS, there is a special flag location (in_debugger) which we
|
||
set to 1. When the dynamic linker sees this flag set, it will set
|
||
a breakpoint at a location known only to itself, after saving the
|
||
original contents of that place and the breakpoint address itself,
|
||
in it's own internal structures. When we resume the inferior, it
|
||
will eventually take a SIGTRAP when it runs into the breakpoint.
|
||
We handle this (in a different place) by restoring the contents of
|
||
the breakpointed location (which is only known after it stops),
|
||
chasing around to locate the shared libraries that have been
|
||
loaded, then resuming.
|
||
|
||
For SVR4, the debugger interface structure contains a member (r_brk)
|
||
which is statically initialized at the time the shared library is
|
||
built, to the offset of a function (_r_debug_state) which is guaran-
|
||
teed to be called once before mapping in a library, and again when
|
||
the mapping is complete. At the time we are examining this member,
|
||
it contains only the unrelocated offset of the function, so we have
|
||
to do our own relocation. Later, when the dynamic linker actually
|
||
runs, it relocates r_brk to be the actual address of _r_debug_state().
|
||
|
||
The debugger interface structure also contains an enumeration which
|
||
is set to either RT_ADD or RT_DELETE prior to changing the mapping,
|
||
depending upon whether or not the library is being mapped or unmapped,
|
||
and then set to RT_CONSISTENT after the library is mapped/unmapped. */
|
||
|
||
static int
|
||
enable_break (struct svr4_info *info, int from_tty)
|
||
{
|
||
struct minimal_symbol *msymbol;
|
||
const char * const *bkpt_namep;
|
||
asection *interp_sect;
|
||
gdb_byte *interp_name;
|
||
CORE_ADDR sym_addr;
|
||
|
||
info->interp_text_sect_low = info->interp_text_sect_high = 0;
|
||
info->interp_plt_sect_low = info->interp_plt_sect_high = 0;
|
||
|
||
/* If we already have a shared library list in the target, and
|
||
r_debug contains r_brk, set the breakpoint there - this should
|
||
mean r_brk has already been relocated. Assume the dynamic linker
|
||
is the object containing r_brk. */
|
||
|
||
solib_add (NULL, from_tty, ¤t_target, auto_solib_add);
|
||
sym_addr = 0;
|
||
if (info->debug_base && solib_svr4_r_map (info) != 0)
|
||
sym_addr = solib_svr4_r_brk (info);
|
||
|
||
if (sym_addr != 0)
|
||
{
|
||
struct obj_section *os;
|
||
|
||
sym_addr = gdbarch_addr_bits_remove
|
||
(target_gdbarch, gdbarch_convert_from_func_ptr_addr (target_gdbarch,
|
||
sym_addr,
|
||
¤t_target));
|
||
|
||
/* On at least some versions of Solaris there's a dynamic relocation
|
||
on _r_debug.r_brk and SYM_ADDR may not be relocated yet, e.g., if
|
||
we get control before the dynamic linker has self-relocated.
|
||
Check if SYM_ADDR is in a known section, if it is assume we can
|
||
trust its value. This is just a heuristic though, it could go away
|
||
or be replaced if it's getting in the way.
|
||
|
||
On ARM we need to know whether the ISA of rtld_db_dlactivity (or
|
||
however it's spelled in your particular system) is ARM or Thumb.
|
||
That knowledge is encoded in the address, if it's Thumb the low bit
|
||
is 1. However, we've stripped that info above and it's not clear
|
||
what all the consequences are of passing a non-addr_bits_remove'd
|
||
address to create_solib_event_breakpoint. The call to
|
||
find_pc_section verifies we know about the address and have some
|
||
hope of computing the right kind of breakpoint to use (via
|
||
symbol info). It does mean that GDB needs to be pointed at a
|
||
non-stripped version of the dynamic linker in order to obtain
|
||
information it already knows about. Sigh. */
|
||
|
||
os = find_pc_section (sym_addr);
|
||
if (os != NULL)
|
||
{
|
||
/* Record the relocated start and end address of the dynamic linker
|
||
text and plt section for svr4_in_dynsym_resolve_code. */
|
||
bfd *tmp_bfd;
|
||
CORE_ADDR load_addr;
|
||
|
||
tmp_bfd = os->objfile->obfd;
|
||
load_addr = ANOFFSET (os->objfile->section_offsets,
|
||
os->objfile->sect_index_text);
|
||
|
||
interp_sect = bfd_get_section_by_name (tmp_bfd, ".text");
|
||
if (interp_sect)
|
||
{
|
||
info->interp_text_sect_low =
|
||
bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
|
||
info->interp_text_sect_high =
|
||
info->interp_text_sect_low
|
||
+ bfd_section_size (tmp_bfd, interp_sect);
|
||
}
|
||
interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt");
|
||
if (interp_sect)
|
||
{
|
||
info->interp_plt_sect_low =
|
||
bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
|
||
info->interp_plt_sect_high =
|
||
info->interp_plt_sect_low
|
||
+ bfd_section_size (tmp_bfd, interp_sect);
|
||
}
|
||
|
||
create_solib_event_breakpoint (target_gdbarch, sym_addr);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
/* Find the program interpreter; if not found, warn the user and drop
|
||
into the old breakpoint at symbol code. */
|
||
interp_name = find_program_interpreter ();
|
||
if (interp_name)
|
||
{
|
||
CORE_ADDR load_addr = 0;
|
||
int load_addr_found = 0;
|
||
int loader_found_in_list = 0;
|
||
struct so_list *so;
|
||
bfd *tmp_bfd = NULL;
|
||
struct target_ops *tmp_bfd_target;
|
||
volatile struct gdb_exception ex;
|
||
|
||
sym_addr = 0;
|
||
|
||
/* Now we need to figure out where the dynamic linker was
|
||
loaded so that we can load its symbols and place a breakpoint
|
||
in the dynamic linker itself.
|
||
|
||
This address is stored on the stack. However, I've been unable
|
||
to find any magic formula to find it for Solaris (appears to
|
||
be trivial on GNU/Linux). Therefore, we have to try an alternate
|
||
mechanism to find the dynamic linker's base address. */
|
||
|
||
TRY_CATCH (ex, RETURN_MASK_ALL)
|
||
{
|
||
tmp_bfd = solib_bfd_open (interp_name);
|
||
}
|
||
if (tmp_bfd == NULL)
|
||
goto bkpt_at_symbol;
|
||
|
||
/* Now convert the TMP_BFD into a target. That way target, as
|
||
well as BFD operations can be used. */
|
||
tmp_bfd_target = target_bfd_reopen (tmp_bfd);
|
||
/* target_bfd_reopen acquired its own reference, so we can
|
||
release ours now. */
|
||
gdb_bfd_unref (tmp_bfd);
|
||
|
||
/* On a running target, we can get the dynamic linker's base
|
||
address from the shared library table. */
|
||
so = master_so_list ();
|
||
while (so)
|
||
{
|
||
if (svr4_same_1 (interp_name, so->so_original_name))
|
||
{
|
||
load_addr_found = 1;
|
||
loader_found_in_list = 1;
|
||
load_addr = lm_addr_check (so, tmp_bfd);
|
||
break;
|
||
}
|
||
so = so->next;
|
||
}
|
||
|
||
/* If we were not able to find the base address of the loader
|
||
from our so_list, then try using the AT_BASE auxilliary entry. */
|
||
if (!load_addr_found)
|
||
if (target_auxv_search (¤t_target, AT_BASE, &load_addr) > 0)
|
||
{
|
||
int addr_bit = gdbarch_addr_bit (target_gdbarch);
|
||
|
||
/* Ensure LOAD_ADDR has proper sign in its possible upper bits so
|
||
that `+ load_addr' will overflow CORE_ADDR width not creating
|
||
invalid addresses like 0x101234567 for 32bit inferiors on 64bit
|
||
GDB. */
|
||
|
||
if (addr_bit < (sizeof (CORE_ADDR) * HOST_CHAR_BIT))
|
||
{
|
||
CORE_ADDR space_size = (CORE_ADDR) 1 << addr_bit;
|
||
CORE_ADDR tmp_entry_point = exec_entry_point (tmp_bfd,
|
||
tmp_bfd_target);
|
||
|
||
gdb_assert (load_addr < space_size);
|
||
|
||
/* TMP_ENTRY_POINT exceeding SPACE_SIZE would be for prelinked
|
||
64bit ld.so with 32bit executable, it should not happen. */
|
||
|
||
if (tmp_entry_point < space_size
|
||
&& tmp_entry_point + load_addr >= space_size)
|
||
load_addr -= space_size;
|
||
}
|
||
|
||
load_addr_found = 1;
|
||
}
|
||
|
||
/* Otherwise we find the dynamic linker's base address by examining
|
||
the current pc (which should point at the entry point for the
|
||
dynamic linker) and subtracting the offset of the entry point.
|
||
|
||
This is more fragile than the previous approaches, but is a good
|
||
fallback method because it has actually been working well in
|
||
most cases. */
|
||
if (!load_addr_found)
|
||
{
|
||
struct regcache *regcache
|
||
= get_thread_arch_regcache (inferior_ptid, target_gdbarch);
|
||
|
||
load_addr = (regcache_read_pc (regcache)
|
||
- exec_entry_point (tmp_bfd, tmp_bfd_target));
|
||
}
|
||
|
||
if (!loader_found_in_list)
|
||
{
|
||
info->debug_loader_name = xstrdup (interp_name);
|
||
info->debug_loader_offset_p = 1;
|
||
info->debug_loader_offset = load_addr;
|
||
solib_add (NULL, from_tty, ¤t_target, auto_solib_add);
|
||
}
|
||
|
||
/* Record the relocated start and end address of the dynamic linker
|
||
text and plt section for svr4_in_dynsym_resolve_code. */
|
||
interp_sect = bfd_get_section_by_name (tmp_bfd, ".text");
|
||
if (interp_sect)
|
||
{
|
||
info->interp_text_sect_low =
|
||
bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
|
||
info->interp_text_sect_high =
|
||
info->interp_text_sect_low
|
||
+ bfd_section_size (tmp_bfd, interp_sect);
|
||
}
|
||
interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt");
|
||
if (interp_sect)
|
||
{
|
||
info->interp_plt_sect_low =
|
||
bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
|
||
info->interp_plt_sect_high =
|
||
info->interp_plt_sect_low
|
||
+ bfd_section_size (tmp_bfd, interp_sect);
|
||
}
|
||
|
||
/* Now try to set a breakpoint in the dynamic linker. */
|
||
for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++)
|
||
{
|
||
sym_addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name_and_sec_flags,
|
||
(void *) *bkpt_namep);
|
||
if (sym_addr != 0)
|
||
break;
|
||
}
|
||
|
||
if (sym_addr != 0)
|
||
/* Convert 'sym_addr' from a function pointer to an address.
|
||
Because we pass tmp_bfd_target instead of the current
|
||
target, this will always produce an unrelocated value. */
|
||
sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch,
|
||
sym_addr,
|
||
tmp_bfd_target);
|
||
|
||
/* We're done with both the temporary bfd and target. Closing
|
||
the target closes the underlying bfd, because it holds the
|
||
only remaining reference. */
|
||
target_close (tmp_bfd_target, 0);
|
||
|
||
if (sym_addr != 0)
|
||
{
|
||
create_solib_event_breakpoint (target_gdbarch, load_addr + sym_addr);
|
||
xfree (interp_name);
|
||
return 1;
|
||
}
|
||
|
||
/* For whatever reason we couldn't set a breakpoint in the dynamic
|
||
linker. Warn and drop into the old code. */
|
||
bkpt_at_symbol:
|
||
xfree (interp_name);
|
||
warning (_("Unable to find dynamic linker breakpoint function.\n"
|
||
"GDB will be unable to debug shared library initializers\n"
|
||
"and track explicitly loaded dynamic code."));
|
||
}
|
||
|
||
/* Scan through the lists of symbols, trying to look up the symbol and
|
||
set a breakpoint there. Terminate loop when we/if we succeed. */
|
||
|
||
for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++)
|
||
{
|
||
msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile);
|
||
if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
|
||
{
|
||
sym_addr = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch,
|
||
sym_addr,
|
||
¤t_target);
|
||
create_solib_event_breakpoint (target_gdbarch, sym_addr);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
if (interp_name != NULL && !current_inferior ()->attach_flag)
|
||
{
|
||
for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++)
|
||
{
|
||
msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile);
|
||
if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
|
||
{
|
||
sym_addr = SYMBOL_VALUE_ADDRESS (msymbol);
|
||
sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch,
|
||
sym_addr,
|
||
¤t_target);
|
||
create_solib_event_breakpoint (target_gdbarch, sym_addr);
|
||
return 1;
|
||
}
|
||
}
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* Implement the "special_symbol_handling" target_so_ops method. */
|
||
|
||
static void
|
||
svr4_special_symbol_handling (void)
|
||
{
|
||
/* Nothing to do. */
|
||
}
|
||
|
||
/* Read the ELF program headers from ABFD. Return the contents and
|
||
set *PHDRS_SIZE to the size of the program headers. */
|
||
|
||
static gdb_byte *
|
||
read_program_headers_from_bfd (bfd *abfd, int *phdrs_size)
|
||
{
|
||
Elf_Internal_Ehdr *ehdr;
|
||
gdb_byte *buf;
|
||
|
||
ehdr = elf_elfheader (abfd);
|
||
|
||
*phdrs_size = ehdr->e_phnum * ehdr->e_phentsize;
|
||
if (*phdrs_size == 0)
|
||
return NULL;
|
||
|
||
buf = xmalloc (*phdrs_size);
|
||
if (bfd_seek (abfd, ehdr->e_phoff, SEEK_SET) != 0
|
||
|| bfd_bread (buf, *phdrs_size, abfd) != *phdrs_size)
|
||
{
|
||
xfree (buf);
|
||
return NULL;
|
||
}
|
||
|
||
return buf;
|
||
}
|
||
|
||
/* Return 1 and fill *DISPLACEMENTP with detected PIE offset of inferior
|
||
exec_bfd. Otherwise return 0.
|
||
|
||
We relocate all of the sections by the same amount. This
|
||
behavior is mandated by recent editions of the System V ABI.
|
||
According to the System V Application Binary Interface,
|
||
Edition 4.1, page 5-5:
|
||
|
||
... Though the system chooses virtual addresses for
|
||
individual processes, it maintains the segments' relative
|
||
positions. Because position-independent code uses relative
|
||
addressesing between segments, the difference between
|
||
virtual addresses in memory must match the difference
|
||
between virtual addresses in the file. The difference
|
||
between the virtual address of any segment in memory and
|
||
the corresponding virtual address in the file is thus a
|
||
single constant value for any one executable or shared
|
||
object in a given process. This difference is the base
|
||
address. One use of the base address is to relocate the
|
||
memory image of the program during dynamic linking.
|
||
|
||
The same language also appears in Edition 4.0 of the System V
|
||
ABI and is left unspecified in some of the earlier editions.
|
||
|
||
Decide if the objfile needs to be relocated. As indicated above, we will
|
||
only be here when execution is stopped. But during attachment PC can be at
|
||
arbitrary address therefore regcache_read_pc can be misleading (contrary to
|
||
the auxv AT_ENTRY value). Moreover for executable with interpreter section
|
||
regcache_read_pc would point to the interpreter and not the main executable.
|
||
|
||
So, to summarize, relocations are necessary when the start address obtained
|
||
from the executable is different from the address in auxv AT_ENTRY entry.
|
||
|
||
[ The astute reader will note that we also test to make sure that
|
||
the executable in question has the DYNAMIC flag set. It is my
|
||
opinion that this test is unnecessary (undesirable even). It
|
||
was added to avoid inadvertent relocation of an executable
|
||
whose e_type member in the ELF header is not ET_DYN. There may
|
||
be a time in the future when it is desirable to do relocations
|
||
on other types of files as well in which case this condition
|
||
should either be removed or modified to accomodate the new file
|
||
type. - Kevin, Nov 2000. ] */
|
||
|
||
static int
|
||
svr4_exec_displacement (CORE_ADDR *displacementp)
|
||
{
|
||
/* ENTRY_POINT is a possible function descriptor - before
|
||
a call to gdbarch_convert_from_func_ptr_addr. */
|
||
CORE_ADDR entry_point, displacement;
|
||
|
||
if (exec_bfd == NULL)
|
||
return 0;
|
||
|
||
/* Therefore for ELF it is ET_EXEC and not ET_DYN. Both shared libraries
|
||
being executed themselves and PIE (Position Independent Executable)
|
||
executables are ET_DYN. */
|
||
|
||
if ((bfd_get_file_flags (exec_bfd) & DYNAMIC) == 0)
|
||
return 0;
|
||
|
||
if (target_auxv_search (¤t_target, AT_ENTRY, &entry_point) <= 0)
|
||
return 0;
|
||
|
||
displacement = entry_point - bfd_get_start_address (exec_bfd);
|
||
|
||
/* Verify the DISPLACEMENT candidate complies with the required page
|
||
alignment. It is cheaper than the program headers comparison below. */
|
||
|
||
if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour)
|
||
{
|
||
const struct elf_backend_data *elf = get_elf_backend_data (exec_bfd);
|
||
|
||
/* p_align of PT_LOAD segments does not specify any alignment but
|
||
only congruency of addresses:
|
||
p_offset % p_align == p_vaddr % p_align
|
||
Kernel is free to load the executable with lower alignment. */
|
||
|
||
if ((displacement & (elf->minpagesize - 1)) != 0)
|
||
return 0;
|
||
}
|
||
|
||
/* Verify that the auxilliary vector describes the same file as exec_bfd, by
|
||
comparing their program headers. If the program headers in the auxilliary
|
||
vector do not match the program headers in the executable, then we are
|
||
looking at a different file than the one used by the kernel - for
|
||
instance, "gdb program" connected to "gdbserver :PORT ld.so program". */
|
||
|
||
if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour)
|
||
{
|
||
/* Be optimistic and clear OK only if GDB was able to verify the headers
|
||
really do not match. */
|
||
int phdrs_size, phdrs2_size, ok = 1;
|
||
gdb_byte *buf, *buf2;
|
||
int arch_size;
|
||
|
||
buf = read_program_header (-1, &phdrs_size, &arch_size);
|
||
buf2 = read_program_headers_from_bfd (exec_bfd, &phdrs2_size);
|
||
if (buf != NULL && buf2 != NULL)
|
||
{
|
||
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
|
||
|
||
/* We are dealing with three different addresses. EXEC_BFD
|
||
represents current address in on-disk file. target memory content
|
||
may be different from EXEC_BFD as the file may have been prelinked
|
||
to a different address after the executable has been loaded.
|
||
Moreover the address of placement in target memory can be
|
||
different from what the program headers in target memory say -
|
||
this is the goal of PIE.
|
||
|
||
Detected DISPLACEMENT covers both the offsets of PIE placement and
|
||
possible new prelink performed after start of the program. Here
|
||
relocate BUF and BUF2 just by the EXEC_BFD vs. target memory
|
||
content offset for the verification purpose. */
|
||
|
||
if (phdrs_size != phdrs2_size
|
||
|| bfd_get_arch_size (exec_bfd) != arch_size)
|
||
ok = 0;
|
||
else if (arch_size == 32
|
||
&& phdrs_size >= sizeof (Elf32_External_Phdr)
|
||
&& phdrs_size % sizeof (Elf32_External_Phdr) == 0)
|
||
{
|
||
Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header;
|
||
Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr;
|
||
CORE_ADDR displacement = 0;
|
||
int i;
|
||
|
||
/* DISPLACEMENT could be found more easily by the difference of
|
||
ehdr2->e_entry. But we haven't read the ehdr yet, and we
|
||
already have enough information to compute that displacement
|
||
with what we've read. */
|
||
|
||
for (i = 0; i < ehdr2->e_phnum; i++)
|
||
if (phdr2[i].p_type == PT_LOAD)
|
||
{
|
||
Elf32_External_Phdr *phdrp;
|
||
gdb_byte *buf_vaddr_p, *buf_paddr_p;
|
||
CORE_ADDR vaddr, paddr;
|
||
CORE_ADDR displacement_vaddr = 0;
|
||
CORE_ADDR displacement_paddr = 0;
|
||
|
||
phdrp = &((Elf32_External_Phdr *) buf)[i];
|
||
buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr;
|
||
buf_paddr_p = (gdb_byte *) &phdrp->p_paddr;
|
||
|
||
vaddr = extract_unsigned_integer (buf_vaddr_p, 4,
|
||
byte_order);
|
||
displacement_vaddr = vaddr - phdr2[i].p_vaddr;
|
||
|
||
paddr = extract_unsigned_integer (buf_paddr_p, 4,
|
||
byte_order);
|
||
displacement_paddr = paddr - phdr2[i].p_paddr;
|
||
|
||
if (displacement_vaddr == displacement_paddr)
|
||
displacement = displacement_vaddr;
|
||
|
||
break;
|
||
}
|
||
|
||
/* Now compare BUF and BUF2 with optional DISPLACEMENT. */
|
||
|
||
for (i = 0; i < phdrs_size / sizeof (Elf32_External_Phdr); i++)
|
||
{
|
||
Elf32_External_Phdr *phdrp;
|
||
Elf32_External_Phdr *phdr2p;
|
||
gdb_byte *buf_vaddr_p, *buf_paddr_p;
|
||
CORE_ADDR vaddr, paddr;
|
||
asection *plt2_asect;
|
||
|
||
phdrp = &((Elf32_External_Phdr *) buf)[i];
|
||
buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr;
|
||
buf_paddr_p = (gdb_byte *) &phdrp->p_paddr;
|
||
phdr2p = &((Elf32_External_Phdr *) buf2)[i];
|
||
|
||
/* PT_GNU_STACK is an exception by being never relocated by
|
||
prelink as its addresses are always zero. */
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
|
||
/* Check also other adjustment combinations - PR 11786. */
|
||
|
||
vaddr = extract_unsigned_integer (buf_vaddr_p, 4,
|
||
byte_order);
|
||
vaddr -= displacement;
|
||
store_unsigned_integer (buf_vaddr_p, 4, byte_order, vaddr);
|
||
|
||
paddr = extract_unsigned_integer (buf_paddr_p, 4,
|
||
byte_order);
|
||
paddr -= displacement;
|
||
store_unsigned_integer (buf_paddr_p, 4, byte_order, paddr);
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
|
||
/* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */
|
||
plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt");
|
||
if (plt2_asect)
|
||
{
|
||
int content2;
|
||
gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz;
|
||
CORE_ADDR filesz;
|
||
|
||
content2 = (bfd_get_section_flags (exec_bfd, plt2_asect)
|
||
& SEC_HAS_CONTENTS) != 0;
|
||
|
||
filesz = extract_unsigned_integer (buf_filesz_p, 4,
|
||
byte_order);
|
||
|
||
/* PLT2_ASECT is from on-disk file (exec_bfd) while
|
||
FILESZ is from the in-memory image. */
|
||
if (content2)
|
||
filesz += bfd_get_section_size (plt2_asect);
|
||
else
|
||
filesz -= bfd_get_section_size (plt2_asect);
|
||
|
||
store_unsigned_integer (buf_filesz_p, 4, byte_order,
|
||
filesz);
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
}
|
||
|
||
ok = 0;
|
||
break;
|
||
}
|
||
}
|
||
else if (arch_size == 64
|
||
&& phdrs_size >= sizeof (Elf64_External_Phdr)
|
||
&& phdrs_size % sizeof (Elf64_External_Phdr) == 0)
|
||
{
|
||
Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header;
|
||
Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr;
|
||
CORE_ADDR displacement = 0;
|
||
int i;
|
||
|
||
/* DISPLACEMENT could be found more easily by the difference of
|
||
ehdr2->e_entry. But we haven't read the ehdr yet, and we
|
||
already have enough information to compute that displacement
|
||
with what we've read. */
|
||
|
||
for (i = 0; i < ehdr2->e_phnum; i++)
|
||
if (phdr2[i].p_type == PT_LOAD)
|
||
{
|
||
Elf64_External_Phdr *phdrp;
|
||
gdb_byte *buf_vaddr_p, *buf_paddr_p;
|
||
CORE_ADDR vaddr, paddr;
|
||
CORE_ADDR displacement_vaddr = 0;
|
||
CORE_ADDR displacement_paddr = 0;
|
||
|
||
phdrp = &((Elf64_External_Phdr *) buf)[i];
|
||
buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr;
|
||
buf_paddr_p = (gdb_byte *) &phdrp->p_paddr;
|
||
|
||
vaddr = extract_unsigned_integer (buf_vaddr_p, 8,
|
||
byte_order);
|
||
displacement_vaddr = vaddr - phdr2[i].p_vaddr;
|
||
|
||
paddr = extract_unsigned_integer (buf_paddr_p, 8,
|
||
byte_order);
|
||
displacement_paddr = paddr - phdr2[i].p_paddr;
|
||
|
||
if (displacement_vaddr == displacement_paddr)
|
||
displacement = displacement_vaddr;
|
||
|
||
break;
|
||
}
|
||
|
||
/* Now compare BUF and BUF2 with optional DISPLACEMENT. */
|
||
|
||
for (i = 0; i < phdrs_size / sizeof (Elf64_External_Phdr); i++)
|
||
{
|
||
Elf64_External_Phdr *phdrp;
|
||
Elf64_External_Phdr *phdr2p;
|
||
gdb_byte *buf_vaddr_p, *buf_paddr_p;
|
||
CORE_ADDR vaddr, paddr;
|
||
asection *plt2_asect;
|
||
|
||
phdrp = &((Elf64_External_Phdr *) buf)[i];
|
||
buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr;
|
||
buf_paddr_p = (gdb_byte *) &phdrp->p_paddr;
|
||
phdr2p = &((Elf64_External_Phdr *) buf2)[i];
|
||
|
||
/* PT_GNU_STACK is an exception by being never relocated by
|
||
prelink as its addresses are always zero. */
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
|
||
/* Check also other adjustment combinations - PR 11786. */
|
||
|
||
vaddr = extract_unsigned_integer (buf_vaddr_p, 8,
|
||
byte_order);
|
||
vaddr -= displacement;
|
||
store_unsigned_integer (buf_vaddr_p, 8, byte_order, vaddr);
|
||
|
||
paddr = extract_unsigned_integer (buf_paddr_p, 8,
|
||
byte_order);
|
||
paddr -= displacement;
|
||
store_unsigned_integer (buf_paddr_p, 8, byte_order, paddr);
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
|
||
/* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */
|
||
plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt");
|
||
if (plt2_asect)
|
||
{
|
||
int content2;
|
||
gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz;
|
||
CORE_ADDR filesz;
|
||
|
||
content2 = (bfd_get_section_flags (exec_bfd, plt2_asect)
|
||
& SEC_HAS_CONTENTS) != 0;
|
||
|
||
filesz = extract_unsigned_integer (buf_filesz_p, 8,
|
||
byte_order);
|
||
|
||
/* PLT2_ASECT is from on-disk file (exec_bfd) while
|
||
FILESZ is from the in-memory image. */
|
||
if (content2)
|
||
filesz += bfd_get_section_size (plt2_asect);
|
||
else
|
||
filesz -= bfd_get_section_size (plt2_asect);
|
||
|
||
store_unsigned_integer (buf_filesz_p, 8, byte_order,
|
||
filesz);
|
||
|
||
if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0)
|
||
continue;
|
||
}
|
||
|
||
ok = 0;
|
||
break;
|
||
}
|
||
}
|
||
else
|
||
ok = 0;
|
||
}
|
||
|
||
xfree (buf);
|
||
xfree (buf2);
|
||
|
||
if (!ok)
|
||
return 0;
|
||
}
|
||
|
||
if (info_verbose)
|
||
{
|
||
/* It can be printed repeatedly as there is no easy way to check
|
||
the executable symbols/file has been already relocated to
|
||
displacement. */
|
||
|
||
printf_unfiltered (_("Using PIE (Position Independent Executable) "
|
||
"displacement %s for \"%s\".\n"),
|
||
paddress (target_gdbarch, displacement),
|
||
bfd_get_filename (exec_bfd));
|
||
}
|
||
|
||
*displacementp = displacement;
|
||
return 1;
|
||
}
|
||
|
||
/* Relocate the main executable. This function should be called upon
|
||
stopping the inferior process at the entry point to the program.
|
||
The entry point from BFD is compared to the AT_ENTRY of AUXV and if they are
|
||
different, the main executable is relocated by the proper amount. */
|
||
|
||
static void
|
||
svr4_relocate_main_executable (void)
|
||
{
|
||
CORE_ADDR displacement;
|
||
|
||
/* If we are re-running this executable, SYMFILE_OBJFILE->SECTION_OFFSETS
|
||
probably contains the offsets computed using the PIE displacement
|
||
from the previous run, which of course are irrelevant for this run.
|
||
So we need to determine the new PIE displacement and recompute the
|
||
section offsets accordingly, even if SYMFILE_OBJFILE->SECTION_OFFSETS
|
||
already contains pre-computed offsets.
|
||
|
||
If we cannot compute the PIE displacement, either:
|
||
|
||
- The executable is not PIE.
|
||
|
||
- SYMFILE_OBJFILE does not match the executable started in the target.
|
||
This can happen for main executable symbols loaded at the host while
|
||
`ld.so --ld-args main-executable' is loaded in the target.
|
||
|
||
Then we leave the section offsets untouched and use them as is for
|
||
this run. Either:
|
||
|
||
- These section offsets were properly reset earlier, and thus
|
||
already contain the correct values. This can happen for instance
|
||
when reconnecting via the remote protocol to a target that supports
|
||
the `qOffsets' packet.
|
||
|
||
- The section offsets were not reset earlier, and the best we can
|
||
hope is that the old offsets are still applicable to the new run. */
|
||
|
||
if (! svr4_exec_displacement (&displacement))
|
||
return;
|
||
|
||
/* Even DISPLACEMENT 0 is a valid new difference of in-memory vs. in-file
|
||
addresses. */
|
||
|
||
if (symfile_objfile)
|
||
{
|
||
struct section_offsets *new_offsets;
|
||
int i;
|
||
|
||
new_offsets = alloca (symfile_objfile->num_sections
|
||
* sizeof (*new_offsets));
|
||
|
||
for (i = 0; i < symfile_objfile->num_sections; i++)
|
||
new_offsets->offsets[i] = displacement;
|
||
|
||
objfile_relocate (symfile_objfile, new_offsets);
|
||
}
|
||
else if (exec_bfd)
|
||
{
|
||
asection *asect;
|
||
|
||
for (asect = exec_bfd->sections; asect != NULL; asect = asect->next)
|
||
exec_set_section_address (bfd_get_filename (exec_bfd), asect->index,
|
||
(bfd_section_vma (exec_bfd, asect)
|
||
+ displacement));
|
||
}
|
||
}
|
||
|
||
/* Implement the "create_inferior_hook" target_solib_ops method.
|
||
|
||
For SVR4 executables, this first instruction is either the first
|
||
instruction in the dynamic linker (for dynamically linked
|
||
executables) or the instruction at "start" for statically linked
|
||
executables. For dynamically linked executables, the system
|
||
first exec's /lib/libc.so.N, which contains the dynamic linker,
|
||
and starts it running. The dynamic linker maps in any needed
|
||
shared libraries, maps in the actual user executable, and then
|
||
jumps to "start" in the user executable.
|
||
|
||
We can arrange to cooperate with the dynamic linker to discover the
|
||
names of shared libraries that are dynamically linked, and the base
|
||
addresses to which they are linked.
|
||
|
||
This function is responsible for discovering those names and
|
||
addresses, and saving sufficient information about them to allow
|
||
their symbols to be read at a later time.
|
||
|
||
FIXME
|
||
|
||
Between enable_break() and disable_break(), this code does not
|
||
properly handle hitting breakpoints which the user might have
|
||
set in the startup code or in the dynamic linker itself. Proper
|
||
handling will probably have to wait until the implementation is
|
||
changed to use the "breakpoint handler function" method.
|
||
|
||
Also, what if child has exit()ed? Must exit loop somehow. */
|
||
|
||
static void
|
||
svr4_solib_create_inferior_hook (int from_tty)
|
||
{
|
||
#if defined(_SCO_DS)
|
||
struct inferior *inf;
|
||
struct thread_info *tp;
|
||
#endif /* defined(_SCO_DS) */
|
||
struct svr4_info *info;
|
||
|
||
info = get_svr4_info ();
|
||
|
||
/* Relocate the main executable if necessary. */
|
||
svr4_relocate_main_executable ();
|
||
|
||
/* No point setting a breakpoint in the dynamic linker if we can't
|
||
hit it (e.g., a core file, or a trace file). */
|
||
if (!target_has_execution)
|
||
return;
|
||
|
||
if (!svr4_have_link_map_offsets ())
|
||
return;
|
||
|
||
if (!enable_break (info, from_tty))
|
||
return;
|
||
|
||
#if defined(_SCO_DS)
|
||
/* SCO needs the loop below, other systems should be using the
|
||
special shared library breakpoints and the shared library breakpoint
|
||
service routine.
|
||
|
||
Now run the target. It will eventually hit the breakpoint, at
|
||
which point all of the libraries will have been mapped in and we
|
||
can go groveling around in the dynamic linker structures to find
|
||
out what we need to know about them. */
|
||
|
||
inf = current_inferior ();
|
||
tp = inferior_thread ();
|
||
|
||
clear_proceed_status ();
|
||
inf->control.stop_soon = STOP_QUIETLY;
|
||
tp->suspend.stop_signal = GDB_SIGNAL_0;
|
||
do
|
||
{
|
||
target_resume (pid_to_ptid (-1), 0, tp->suspend.stop_signal);
|
||
wait_for_inferior ();
|
||
}
|
||
while (tp->suspend.stop_signal != GDB_SIGNAL_TRAP);
|
||
inf->control.stop_soon = NO_STOP_QUIETLY;
|
||
#endif /* defined(_SCO_DS) */
|
||
}
|
||
|
||
static void
|
||
svr4_clear_solib (void)
|
||
{
|
||
struct svr4_info *info;
|
||
|
||
info = get_svr4_info ();
|
||
info->debug_base = 0;
|
||
info->debug_loader_offset_p = 0;
|
||
info->debug_loader_offset = 0;
|
||
xfree (info->debug_loader_name);
|
||
info->debug_loader_name = NULL;
|
||
}
|
||
|
||
/* Clear any bits of ADDR that wouldn't fit in a target-format
|
||
data pointer. "Data pointer" here refers to whatever sort of
|
||
address the dynamic linker uses to manage its sections. At the
|
||
moment, we don't support shared libraries on any processors where
|
||
code and data pointers are different sizes.
|
||
|
||
This isn't really the right solution. What we really need here is
|
||
a way to do arithmetic on CORE_ADDR values that respects the
|
||
natural pointer/address correspondence. (For example, on the MIPS,
|
||
converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to
|
||
sign-extend the value. There, simply truncating the bits above
|
||
gdbarch_ptr_bit, as we do below, is no good.) This should probably
|
||
be a new gdbarch method or something. */
|
||
static CORE_ADDR
|
||
svr4_truncate_ptr (CORE_ADDR addr)
|
||
{
|
||
if (gdbarch_ptr_bit (target_gdbarch) == sizeof (CORE_ADDR) * 8)
|
||
/* We don't need to truncate anything, and the bit twiddling below
|
||
will fail due to overflow problems. */
|
||
return addr;
|
||
else
|
||
return addr & (((CORE_ADDR) 1 << gdbarch_ptr_bit (target_gdbarch)) - 1);
|
||
}
|
||
|
||
|
||
static void
|
||
svr4_relocate_section_addresses (struct so_list *so,
|
||
struct target_section *sec)
|
||
{
|
||
sec->addr = svr4_truncate_ptr (sec->addr + lm_addr_check (so,
|
||
sec->bfd));
|
||
sec->endaddr = svr4_truncate_ptr (sec->endaddr + lm_addr_check (so,
|
||
sec->bfd));
|
||
}
|
||
|
||
|
||
/* Architecture-specific operations. */
|
||
|
||
/* Per-architecture data key. */
|
||
static struct gdbarch_data *solib_svr4_data;
|
||
|
||
struct solib_svr4_ops
|
||
{
|
||
/* Return a description of the layout of `struct link_map'. */
|
||
struct link_map_offsets *(*fetch_link_map_offsets)(void);
|
||
};
|
||
|
||
/* Return a default for the architecture-specific operations. */
|
||
|
||
static void *
|
||
solib_svr4_init (struct obstack *obstack)
|
||
{
|
||
struct solib_svr4_ops *ops;
|
||
|
||
ops = OBSTACK_ZALLOC (obstack, struct solib_svr4_ops);
|
||
ops->fetch_link_map_offsets = NULL;
|
||
return ops;
|
||
}
|
||
|
||
/* Set the architecture-specific `struct link_map_offsets' fetcher for
|
||
GDBARCH to FLMO. Also, install SVR4 solib_ops into GDBARCH. */
|
||
|
||
void
|
||
set_solib_svr4_fetch_link_map_offsets (struct gdbarch *gdbarch,
|
||
struct link_map_offsets *(*flmo) (void))
|
||
{
|
||
struct solib_svr4_ops *ops = gdbarch_data (gdbarch, solib_svr4_data);
|
||
|
||
ops->fetch_link_map_offsets = flmo;
|
||
|
||
set_solib_ops (gdbarch, &svr4_so_ops);
|
||
}
|
||
|
||
/* Fetch a link_map_offsets structure using the architecture-specific
|
||
`struct link_map_offsets' fetcher. */
|
||
|
||
static struct link_map_offsets *
|
||
svr4_fetch_link_map_offsets (void)
|
||
{
|
||
struct solib_svr4_ops *ops = gdbarch_data (target_gdbarch, solib_svr4_data);
|
||
|
||
gdb_assert (ops->fetch_link_map_offsets);
|
||
return ops->fetch_link_map_offsets ();
|
||
}
|
||
|
||
/* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */
|
||
|
||
static int
|
||
svr4_have_link_map_offsets (void)
|
||
{
|
||
struct solib_svr4_ops *ops = gdbarch_data (target_gdbarch, solib_svr4_data);
|
||
|
||
return (ops->fetch_link_map_offsets != NULL);
|
||
}
|
||
|
||
|
||
/* Most OS'es that have SVR4-style ELF dynamic libraries define a
|
||
`struct r_debug' and a `struct link_map' that are binary compatible
|
||
with the origional SVR4 implementation. */
|
||
|
||
/* Fetch (and possibly build) an appropriate `struct link_map_offsets'
|
||
for an ILP32 SVR4 system. */
|
||
|
||
struct link_map_offsets *
|
||
svr4_ilp32_fetch_link_map_offsets (void)
|
||
{
|
||
static struct link_map_offsets lmo;
|
||
static struct link_map_offsets *lmp = NULL;
|
||
|
||
if (lmp == NULL)
|
||
{
|
||
lmp = &lmo;
|
||
|
||
lmo.r_version_offset = 0;
|
||
lmo.r_version_size = 4;
|
||
lmo.r_map_offset = 4;
|
||
lmo.r_brk_offset = 8;
|
||
lmo.r_ldsomap_offset = 20;
|
||
|
||
/* Everything we need is in the first 20 bytes. */
|
||
lmo.link_map_size = 20;
|
||
lmo.l_addr_offset = 0;
|
||
lmo.l_name_offset = 4;
|
||
lmo.l_ld_offset = 8;
|
||
lmo.l_next_offset = 12;
|
||
lmo.l_prev_offset = 16;
|
||
}
|
||
|
||
return lmp;
|
||
}
|
||
|
||
/* Fetch (and possibly build) an appropriate `struct link_map_offsets'
|
||
for an LP64 SVR4 system. */
|
||
|
||
struct link_map_offsets *
|
||
svr4_lp64_fetch_link_map_offsets (void)
|
||
{
|
||
static struct link_map_offsets lmo;
|
||
static struct link_map_offsets *lmp = NULL;
|
||
|
||
if (lmp == NULL)
|
||
{
|
||
lmp = &lmo;
|
||
|
||
lmo.r_version_offset = 0;
|
||
lmo.r_version_size = 4;
|
||
lmo.r_map_offset = 8;
|
||
lmo.r_brk_offset = 16;
|
||
lmo.r_ldsomap_offset = 40;
|
||
|
||
/* Everything we need is in the first 40 bytes. */
|
||
lmo.link_map_size = 40;
|
||
lmo.l_addr_offset = 0;
|
||
lmo.l_name_offset = 8;
|
||
lmo.l_ld_offset = 16;
|
||
lmo.l_next_offset = 24;
|
||
lmo.l_prev_offset = 32;
|
||
}
|
||
|
||
return lmp;
|
||
}
|
||
|
||
|
||
struct target_so_ops svr4_so_ops;
|
||
|
||
/* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a
|
||
different rule for symbol lookup. The lookup begins here in the DSO, not in
|
||
the main executable. */
|
||
|
||
static struct symbol *
|
||
elf_lookup_lib_symbol (const struct objfile *objfile,
|
||
const char *name,
|
||
const domain_enum domain)
|
||
{
|
||
bfd *abfd;
|
||
|
||
if (objfile == symfile_objfile)
|
||
abfd = exec_bfd;
|
||
else
|
||
{
|
||
/* OBJFILE should have been passed as the non-debug one. */
|
||
gdb_assert (objfile->separate_debug_objfile_backlink == NULL);
|
||
|
||
abfd = objfile->obfd;
|
||
}
|
||
|
||
if (abfd == NULL || scan_dyntag (DT_SYMBOLIC, abfd, NULL) != 1)
|
||
return NULL;
|
||
|
||
return lookup_global_symbol_from_objfile (objfile, name, domain);
|
||
}
|
||
|
||
extern initialize_file_ftype _initialize_svr4_solib; /* -Wmissing-prototypes */
|
||
|
||
void
|
||
_initialize_svr4_solib (void)
|
||
{
|
||
solib_svr4_data = gdbarch_data_register_pre_init (solib_svr4_init);
|
||
solib_svr4_pspace_data
|
||
= register_program_space_data_with_cleanup (NULL, svr4_pspace_data_cleanup);
|
||
|
||
svr4_so_ops.relocate_section_addresses = svr4_relocate_section_addresses;
|
||
svr4_so_ops.free_so = svr4_free_so;
|
||
svr4_so_ops.clear_solib = svr4_clear_solib;
|
||
svr4_so_ops.solib_create_inferior_hook = svr4_solib_create_inferior_hook;
|
||
svr4_so_ops.special_symbol_handling = svr4_special_symbol_handling;
|
||
svr4_so_ops.current_sos = svr4_current_sos;
|
||
svr4_so_ops.open_symbol_file_object = open_symbol_file_object;
|
||
svr4_so_ops.in_dynsym_resolve_code = svr4_in_dynsym_resolve_code;
|
||
svr4_so_ops.bfd_open = solib_bfd_open;
|
||
svr4_so_ops.lookup_lib_global_symbol = elf_lookup_lib_symbol;
|
||
svr4_so_ops.same = svr4_same;
|
||
svr4_so_ops.keep_data_in_core = svr4_keep_data_in_core;
|
||
}
|