/* Handle SVR4 shared libraries for GDB, the GNU Debugger.
- Copyright (C) 1990-2019 Free Software Foundation, Inc.
+ Copyright (C) 1990-2020 Free Software Foundation, Inc.
This file is part of GDB.
static void svr4_relocate_main_executable (void);
static void svr4_free_library_list (void *p_list);
static void probes_table_remove_objfile_probes (struct objfile *objfile);
+static void svr4_iterate_over_objfiles_in_search_order (
+ struct gdbarch *gdbarch, iterate_over_objfiles_in_search_order_cb_ftype *cb,
+ void *cb_data, struct objfile *objfile);
+
/* On SVR4 systems, a list of symbols in the dynamic linker where
GDB can try to place a breakpoint to monitor shared library
if (dyninfo_sect == NULL)
goto set_addr;
- dynaddr = bfd_section_vma (abfd, dyninfo_sect);
+ dynaddr = bfd_section_vma (dyninfo_sect);
if (dynaddr + l_addr != l_dynaddr)
{
struct svr4_info
{
- CORE_ADDR debug_base; /* Base of dynamic linker structures. */
+ svr4_info () = default;
+ ~svr4_info ();
+
+ /* Base of dynamic linker structures. */
+ CORE_ADDR debug_base = 0;
/* Validity flag for debug_loader_offset. */
- int debug_loader_offset_p;
+ int debug_loader_offset_p = 0;
/* Load address for the dynamic linker, inferred. */
- CORE_ADDR debug_loader_offset;
+ CORE_ADDR debug_loader_offset = 0;
/* Name of the dynamic linker, valid if debug_loader_offset_p. */
- char *debug_loader_name;
+ char *debug_loader_name = nullptr;
/* Load map address for the main executable. */
- CORE_ADDR main_lm_addr;
+ CORE_ADDR main_lm_addr = 0;
- CORE_ADDR interp_text_sect_low;
- CORE_ADDR interp_text_sect_high;
- CORE_ADDR interp_plt_sect_low;
- CORE_ADDR interp_plt_sect_high;
+ CORE_ADDR interp_text_sect_low = 0;
+ CORE_ADDR interp_text_sect_high = 0;
+ CORE_ADDR interp_plt_sect_low = 0;
+ CORE_ADDR interp_plt_sect_high = 0;
/* Nonzero if the list of objects was last obtained from the target
via qXfer:libraries-svr4:read. */
- int using_xfer;
+ int using_xfer = 0;
/* Table of struct probe_and_action instances, used by the
probes-based interface to map breakpoint addresses to probes
and their associated actions. Lookup is performed using
probe_and_action->prob->address. */
- htab_t probes_table;
+ htab_up probes_table;
/* List of objects loaded into the inferior, used by the probes-
based interface. */
- struct so_list *solib_list;
+ struct so_list *solib_list = nullptr;
};
/* Per-program-space data key. */
-static const struct program_space_data *solib_svr4_pspace_data;
+static const struct program_space_key<svr4_info> solib_svr4_pspace_data;
/* Free the probes table. */
static void
free_probes_table (struct svr4_info *info)
{
- if (info->probes_table == NULL)
- return;
-
- htab_delete (info->probes_table);
- info->probes_table = NULL;
+ info->probes_table.reset (nullptr);
}
/* Free the solib list. */
info->solib_list = NULL;
}
-static void
-svr4_pspace_data_cleanup (struct program_space *pspace, void *arg)
+svr4_info::~svr4_info ()
{
- struct svr4_info *info = (struct svr4_info *) arg;
-
- free_probes_table (info);
- free_solib_list (info);
-
- xfree (info);
+ free_solib_list (this);
}
/* Get the svr4 data for program space PSPACE. If none is found yet, add it now.
static struct svr4_info *
get_svr4_info (program_space *pspace)
{
- struct svr4_info *info;
+ struct svr4_info *info = solib_svr4_pspace_data.get (pspace);
- info = (struct svr4_info *) program_space_data (pspace,
- solib_svr4_pspace_data);
- if (info != NULL)
- return info;
+ if (info == NULL)
+ info = solib_svr4_pspace_data.emplace (pspace);
- info = XCNEW (struct svr4_info);
- set_program_space_data (pspace, solib_svr4_pspace_data, info);
return info;
}
interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
if (interp_sect != NULL)
{
- int sect_size = bfd_section_size (exec_bfd, interp_sect);
+ int sect_size = bfd_section_size (interp_sect);
gdb::byte_vector buf (sect_size);
bfd_get_section_contents (exec_bfd, interp_sect, buf.data (), 0,
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);
+ dyn_addr = bfd_section_vma (sect);
}
/* Read in .dynamic from the BFD. We will get the actual value
from memory later. */
- sect_size = bfd_section_size (abfd, sect);
+ sect_size = bfd_section_size (sect);
buf = bufstart = (gdb_byte *) alloca (sect_size);
if (!bfd_get_section_contents (abfd, sect,
buf, 0, sect_size))
{
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 ());
+ enum bfd_endian byte_order = type_byte_order (ptr_type);
ULONGEST version = 0;
try
struct objfile *objfile = (struct objfile *) info;
if (pa->objfile == objfile)
- htab_clear_slot (get_svr4_info (objfile->pspace)->probes_table, slot);
+ htab_clear_slot (get_svr4_info (objfile->pspace)->probes_table.get (),
+ slot);
return 1;
}
{
svr4_info *info = get_svr4_info (objfile->pspace);
if (info->probes_table != nullptr)
- htab_traverse_noresize (info->probes_table,
+ htab_traverse_noresize (info->probes_table.get (),
probes_table_htab_remove_objfile_probes, objfile);
}
/* Create the probes table, if necessary. */
if (info->probes_table == NULL)
- info->probes_table = htab_create_alloc (1, hash_probe_and_action,
- equal_probe_and_action,
- xfree, xcalloc, xfree);
+ info->probes_table.reset (htab_create_alloc (1, hash_probe_and_action,
+ equal_probe_and_action,
+ xfree, xcalloc, xfree));
lookup.address = address;
- slot = htab_find_slot (info->probes_table, &lookup, INSERT);
+ slot = htab_find_slot (info->probes_table.get (), &lookup, INSERT);
gdb_assert (*slot == HTAB_EMPTY_ENTRY);
pa = XCNEW (struct probe_and_action);
void **slot;
lookup.address = address;
- slot = htab_find_slot (info->probes_table, &lookup, NO_INSERT);
+ slot = htab_find_slot (info->probes_table.get (), &lookup, NO_INSERT);
if (slot == NULL)
return NULL;
arg2: struct link_map *new (optional, for incremental updates) */
try
{
- probe_argc = pa->prob->get_argument_count (frame);
+ probe_argc = pa->prob->get_argument_count (get_frame_arch (frame));
}
catch (const gdb_exception_error &ex)
{
disable_probes_interface (svr4_info *info)
{
warning (_("Probes-based dynamic linker interface failed.\n"
- "Reverting to original interface.\n"));
+ "Reverting to original interface."));
free_probes_table (info);
free_solib_list (info);
/* Always locate the debug struct, in case it moved. */
info->debug_base = 0;
if (locate_base (info) == 0)
- return;
+ {
+ /* It's possible for the reloc_complete probe to be triggered before
+ the linker has set the DT_DEBUG pointer (for example, when the
+ linker has finished relocating an LD_AUDIT library or its
+ dependencies). Since we can't yet handle libraries from other link
+ namespaces, we don't lose anything by ignoring them here. */
+ struct value *link_map_id_val;
+ try
+ {
+ link_map_id_val = pa->prob->evaluate_argument (0, frame);
+ }
+ catch (const gdb_exception_error)
+ {
+ link_map_id_val = NULL;
+ }
+ /* glibc and illumos' libc both define LM_ID_BASE as zero. */
+ if (link_map_id_val != NULL && value_as_long (link_map_id_val) != 0)
+ action = DO_NOTHING;
+ else
+ return;
+ }
/* GDB does not currently support libraries loaded via dlmopen
into namespaces other than the initial one. We must ignore
/* Helper function for svr4_update_solib_event_breakpoints. */
-static int
-svr4_update_solib_event_breakpoint (struct breakpoint *b, void *arg)
+static bool
+svr4_update_solib_event_breakpoint (struct breakpoint *b)
{
struct bp_location *loc;
if (b->type != bp_shlib_event)
{
/* Continue iterating. */
- return 0;
+ return false;
}
for (loc = b->loc; loc != NULL; loc = loc->next)
struct svr4_info *info;
struct probe_and_action *pa;
- info = ((struct svr4_info *)
- program_space_data (loc->pspace, solib_svr4_pspace_data));
+ info = solib_svr4_pspace_data.get (loc->pspace);
if (info == NULL || info->probes_table == NULL)
continue;
}
/* Continue iterating. */
- return 0;
+ return false;
}
/* Enable or disable optional solib event breakpoints as appropriate.
static void
svr4_update_solib_event_breakpoints (void)
{
- iterate_over_breakpoints (svr4_update_solib_event_breakpoint, NULL);
+ iterate_over_breakpoints (svr4_update_solib_event_breakpoint);
}
/* Create and register solib event breakpoints. PROBES is an array
svr4_update_solib_event_breakpoints ();
}
+/* Find all the glibc named probes. Only if all of the probes are found, then
+ create them and return true. Otherwise return false. If WITH_PREFIX is set
+ then add "rtld" to the front of the probe names. */
+static bool
+svr4_find_and_create_probe_breakpoints (svr4_info *info,
+ struct gdbarch *gdbarch,
+ struct obj_section *os,
+ bool with_prefix)
+{
+ std::vector<probe *> probes[NUM_PROBES];
+
+ for (int i = 0; i < NUM_PROBES; i++)
+ {
+ const char *name = probe_info[i].name;
+ char buf[32];
+
+ /* Fedora 17 and Red Hat Enterprise Linux 6.2-6.4 shipped with an early
+ version of the probes code in which the probes' names were prefixed
+ with "rtld_" and the "map_failed" probe did not exist. The locations
+ of the probes are otherwise the same, so we check for probes with
+ prefixed names if probes with unprefixed names are not present. */
+ if (with_prefix)
+ {
+ xsnprintf (buf, sizeof (buf), "rtld_%s", name);
+ name = buf;
+ }
+
+ probes[i] = find_probes_in_objfile (os->objfile, "rtld", name);
+
+ /* The "map_failed" probe did not exist in early
+ versions of the probes code in which the probes'
+ names were prefixed with "rtld_". */
+ if (with_prefix && streq (name, "rtld_map_failed"))
+ continue;
+
+ /* Ensure at least one probe for the current name was found. */
+ if (probes[i].empty ())
+ return false;
+
+ /* Ensure probe arguments can be evaluated. */
+ for (probe *p : probes[i])
+ {
+ if (!p->can_evaluate_arguments ())
+ return false;
+ /* This will fail if the probe is invalid. This has been seen on Arm
+ due to references to symbols that have been resolved away. */
+ try
+ {
+ p->get_argument_count (gdbarch);
+ }
+ catch (const gdb_exception_error &ex)
+ {
+ exception_print (gdb_stderr, ex);
+ warning (_("Initializing probes-based dynamic linker interface "
+ "failed.\nReverting to original interface."));
+ return false;
+ }
+ }
+ }
+
+ /* All probes found. Now create them. */
+ svr4_create_probe_breakpoints (info, gdbarch, probes, os->objfile);
+ return true;
+}
+
/* Both the SunOS and the SVR4 dynamic linkers call a marker function
before and after mapping and unmapping shared libraries. The sole
purpose of this method is to allow debuggers to set a breakpoint so
svr4_create_solib_event_breakpoints (svr4_info *info, struct gdbarch *gdbarch,
CORE_ADDR address)
{
- struct obj_section *os;
-
- os = find_pc_section (address);
- if (os != NULL)
- {
- int with_prefix;
-
- for (with_prefix = 0; with_prefix <= 1; with_prefix++)
- {
- std::vector<probe *> probes[NUM_PROBES];
- int all_probes_found = 1;
- int checked_can_use_probe_arguments = 0;
-
- for (int i = 0; i < NUM_PROBES; i++)
- {
- const char *name = probe_info[i].name;
- probe *p;
- char buf[32];
-
- /* Fedora 17 and Red Hat Enterprise Linux 6.2-6.4
- shipped with an early version of the probes code in
- which the probes' names were prefixed with "rtld_"
- and the "map_failed" probe did not exist. The
- locations of the probes are otherwise the same, so
- we check for probes with prefixed names if probes
- with unprefixed names are not present. */
- if (with_prefix)
- {
- xsnprintf (buf, sizeof (buf), "rtld_%s", name);
- name = buf;
- }
-
- probes[i] = find_probes_in_objfile (os->objfile, "rtld", name);
-
- /* The "map_failed" probe did not exist in early
- versions of the probes code in which the probes'
- names were prefixed with "rtld_". */
- if (strcmp (name, "rtld_map_failed") == 0)
- continue;
-
- if (probes[i].empty ())
- {
- all_probes_found = 0;
- break;
- }
-
- /* Ensure probe arguments can be evaluated. */
- if (!checked_can_use_probe_arguments)
- {
- p = probes[i][0];
- if (!p->can_evaluate_arguments ())
- {
- all_probes_found = 0;
- break;
- }
- checked_can_use_probe_arguments = 1;
- }
- }
-
- if (all_probes_found)
- svr4_create_probe_breakpoints (info, gdbarch, probes, os->objfile);
-
- if (all_probes_found)
- return;
- }
- }
+ struct obj_section *os = find_pc_section (address);
- create_solib_event_breakpoint (gdbarch, address);
+ if (os == nullptr
+ || (!svr4_find_and_create_probe_breakpoints (info, gdbarch, os, false)
+ && !svr4_find_and_create_probe_breakpoints (info, gdbarch, os, true)))
+ create_solib_event_breakpoint (gdbarch, address);
}
/* Helper function for gdb_bfd_lookup_symbol. */
CORE_ADDR load_addr;
tmp_bfd = os->objfile->obfd;
- load_addr = ANOFFSET (os->objfile->section_offsets,
- SECT_OFF_TEXT (os->objfile));
+ load_addr = os->objfile->section_offsets[SECT_OFF_TEXT (os->objfile)];
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);
+ info->interp_text_sect_low
+ = bfd_section_vma (interp_sect) + load_addr;
+ info->interp_text_sect_high
+ = info->interp_text_sect_low + bfd_section_size (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);
+ info->interp_plt_sect_low
+ = bfd_section_vma (interp_sect) + load_addr;
+ info->interp_plt_sect_high
+ = info->interp_plt_sect_low + bfd_section_size (interp_sect);
}
svr4_create_solib_event_breakpoints (info, target_gdbarch (), sym_addr);
interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".text");
if (interp_sect)
{
- info->interp_text_sect_low =
- bfd_section_vma (tmp_bfd.get (), interp_sect) + load_addr;
- info->interp_text_sect_high =
- info->interp_text_sect_low
- + bfd_section_size (tmp_bfd.get (), interp_sect);
+ info->interp_text_sect_low
+ = bfd_section_vma (interp_sect) + load_addr;
+ info->interp_text_sect_high
+ = info->interp_text_sect_low + bfd_section_size (interp_sect);
}
interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".plt");
if (interp_sect)
{
- info->interp_plt_sect_low =
- bfd_section_vma (tmp_bfd.get (), interp_sect) + load_addr;
- info->interp_plt_sect_high =
- info->interp_plt_sect_low
- + bfd_section_size (tmp_bfd.get (), interp_sect);
+ info->interp_plt_sect_low
+ = bfd_section_vma (interp_sect) + load_addr;
+ info->interp_plt_sect_high
+ = info->interp_plt_sect_low + bfd_section_size (interp_sect);
}
/* Now try to set a breakpoint in the dynamic linker. */
... 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
+ addressing 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
gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz;
CORE_ADDR filesz;
- content2 = (bfd_get_section_flags (exec_bfd, plt2_asect)
+ content2 = (bfd_section_flags (plt2_asect)
& SEC_HAS_CONTENTS) != 0;
filesz = extract_unsigned_integer (buf_filesz_p, 4,
/* 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);
+ filesz += bfd_section_size (plt2_asect);
else
- filesz -= bfd_get_section_size (plt2_asect);
+ filesz -= bfd_section_size (plt2_asect);
store_unsigned_integer (buf_filesz_p, 4, byte_order,
filesz);
gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz;
CORE_ADDR filesz;
- content2 = (bfd_get_section_flags (exec_bfd, plt2_asect)
+ content2 = (bfd_section_flags (plt2_asect)
& SEC_HAS_CONTENTS) != 0;
filesz = extract_unsigned_integer (buf_filesz_p, 8,
/* 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);
+ filesz += bfd_section_size (plt2_asect);
else
- filesz -= bfd_get_section_size (plt2_asect);
+ filesz -= bfd_section_size (plt2_asect);
store_unsigned_integer (buf_filesz_p, 8, byte_order,
filesz);
if (symfile_objfile)
{
- struct section_offsets *new_offsets;
- int i;
-
- new_offsets = XALLOCAVEC (struct section_offsets,
- symfile_objfile->num_sections);
-
- for (i = 0; i < symfile_objfile->num_sections; i++)
- new_offsets->offsets[i] = displacement;
-
+ section_offsets new_offsets (symfile_objfile->section_offsets.size (),
+ displacement);
objfile_relocate (symfile_objfile, new_offsets);
}
else if (exec_bfd)
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));
+ bfd_section_vma (asect) + displacement);
}
}
ops->fetch_link_map_offsets = flmo;
set_solib_ops (gdbarch, &svr4_so_ops);
+ set_gdbarch_iterate_over_objfiles_in_search_order
+ (gdbarch, svr4_iterate_over_objfiles_in_search_order);
}
/* Fetch a link_map_offsets structure using the architecture-specific
/* 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. */
+ with the original SVR4 implementation. */
/* Fetch (and possibly build) an appropriate `struct link_map_offsets'
for an ILP32 SVR4 system. */
struct target_so_ops svr4_so_ops;
-/* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a
+/* Search order 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 block_symbol
-elf_lookup_lib_symbol (struct objfile *objfile,
- const char *name,
- const domain_enum domain)
+static void
+svr4_iterate_over_objfiles_in_search_order
+ (struct gdbarch *gdbarch,
+ iterate_over_objfiles_in_search_order_cb_ftype *cb,
+ void *cb_data, struct objfile *current_objfile)
{
- bfd *abfd;
-
- if (objfile == symfile_objfile)
- abfd = exec_bfd;
- else
+ bool checked_current_objfile = false;
+ if (current_objfile != nullptr)
{
- /* OBJFILE should have been passed as the non-debug one. */
- gdb_assert (objfile->separate_debug_objfile_backlink == NULL);
+ bfd *abfd;
- abfd = objfile->obfd;
- }
+ if (current_objfile->separate_debug_objfile_backlink != nullptr)
+ current_objfile = current_objfile->separate_debug_objfile_backlink;
- if (abfd == NULL || scan_dyntag (DT_SYMBOLIC, abfd, NULL, NULL) != 1)
- return {};
+ if (current_objfile == symfile_objfile)
+ abfd = exec_bfd;
+ else
+ abfd = current_objfile->obfd;
- return lookup_global_symbol_from_objfile (objfile, name, domain);
+ if (abfd != nullptr
+ && scan_dyntag (DT_SYMBOLIC, abfd, nullptr, nullptr) == 1)
+ {
+ checked_current_objfile = true;
+ if (cb (current_objfile, cb_data) != 0)
+ return;
+ }
+ }
+
+ for (objfile *objfile : current_program_space->objfiles ())
+ {
+ if (checked_current_objfile && objfile == current_objfile)
+ continue;
+ if (cb (objfile, cb_data) != 0)
+ return;
+ }
}
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.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;
svr4_so_ops.update_breakpoints = svr4_update_solib_event_breakpoints;
projects / deliverable / binutils-gdb.git / blobdiff