/* Definitions for targets which report shared library events.
Copyright (C) 2007-2022 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see . */
#include "defs.h"
#include "objfiles.h"
#include "solist.h"
#include "symtab.h"
#include "symfile.h"
#include "target.h"
#include "solib-target.h"
#include
#include "inferior.h"
/* Private data for each loaded library. */
struct lm_info_target : public lm_info_base
{
/* The library's name. The name is normally kept in the struct
so_list; it is only here during XML parsing. */
std::string name;
/* The target can either specify segment bases or section bases, not
both. */
/* The base addresses for each independently relocatable segment of
this shared library. */
std::vector segment_bases;
/* The base addresses for each independently allocatable,
relocatable section of this shared library. */
std::vector section_bases;
/* The cached offsets for each section of this shared library,
determined from SEGMENT_BASES, or SECTION_BASES. */
section_offsets offsets;
};
typedef std::vector> lm_info_vector;
#if !defined(HAVE_LIBEXPAT)
static lm_info_vector
solib_target_parse_libraries (const char *library)
{
static int have_warned;
if (!have_warned)
{
have_warned = 1;
warning (_("Can not parse XML library list; XML support was disabled "
"at compile time"));
}
return lm_info_vector ();
}
#else /* HAVE_LIBEXPAT */
#include "xml-support.h"
/* Handle the start of a element. */
static void
library_list_start_segment (struct gdb_xml_parser *parser,
const struct gdb_xml_element *element,
void *user_data,
std::vector &attributes)
{
lm_info_vector *list = (lm_info_vector *) user_data;
lm_info_target *last = list->back ().get ();
ULONGEST *address_p
= (ULONGEST *) xml_find_attribute (attributes, "address")->value.get ();
CORE_ADDR address = (CORE_ADDR) *address_p;
if (!last->section_bases.empty ())
gdb_xml_error (parser,
_("Library list with both segments and sections"));
last->segment_bases.push_back (address);
}
static void
library_list_start_section (struct gdb_xml_parser *parser,
const struct gdb_xml_element *element,
void *user_data,
std::vector &attributes)
{
lm_info_vector *list = (lm_info_vector *) user_data;
lm_info_target *last = list->back ().get ();
ULONGEST *address_p
= (ULONGEST *) xml_find_attribute (attributes, "address")->value.get ();
CORE_ADDR address = (CORE_ADDR) *address_p;
if (!last->segment_bases.empty ())
gdb_xml_error (parser,
_("Library list with both segments and sections"));
last->section_bases.push_back (address);
}
/* Handle the start of a element. */
static void
library_list_start_library (struct gdb_xml_parser *parser,
const struct gdb_xml_element *element,
void *user_data,
std::vector &attributes)
{
lm_info_vector *list = (lm_info_vector *) user_data;
lm_info_target *item = new lm_info_target;
item->name
= (const char *) xml_find_attribute (attributes, "name")->value.get ();
list->emplace_back (item);
}
static void
library_list_end_library (struct gdb_xml_parser *parser,
const struct gdb_xml_element *element,
void *user_data, const char *body_text)
{
lm_info_vector *list = (lm_info_vector *) user_data;
lm_info_target *lm_info = list->back ().get ();
if (lm_info->segment_bases.empty () && lm_info->section_bases.empty ())
gdb_xml_error (parser, _("No segment or section bases defined"));
}
/* Handle the start of a element. */
static void
library_list_start_list (struct gdb_xml_parser *parser,
const struct gdb_xml_element *element,
void *user_data,
std::vector &attributes)
{
struct gdb_xml_value *version = xml_find_attribute (attributes, "version");
/* #FIXED attribute may be omitted, Expat returns NULL in such case. */
if (version != NULL)
{
const char *string = (const char *) version->value.get ();
if (strcmp (string, "1.0") != 0)
gdb_xml_error (parser,
_("Library list has unsupported version \"%s\""),
string);
}
}
/* The allowed elements and attributes for an XML library list.
The root element is a . */
static const struct gdb_xml_attribute segment_attributes[] = {
{ "address", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
};
static const struct gdb_xml_attribute section_attributes[] = {
{ "address", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
};
static const struct gdb_xml_element library_children[] = {
{ "segment", segment_attributes, NULL,
GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
library_list_start_segment, NULL },
{ "section", section_attributes, NULL,
GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
library_list_start_section, NULL },
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
};
static const struct gdb_xml_attribute library_attributes[] = {
{ "name", GDB_XML_AF_NONE, NULL, NULL },
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
};
static const struct gdb_xml_element library_list_children[] = {
{ "library", library_attributes, library_children,
GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
library_list_start_library, library_list_end_library },
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
};
static const struct gdb_xml_attribute library_list_attributes[] = {
{ "version", GDB_XML_AF_OPTIONAL, NULL, NULL },
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
};
static const struct gdb_xml_element library_list_elements[] = {
{ "library-list", library_list_attributes, library_list_children,
GDB_XML_EF_NONE, library_list_start_list, NULL },
{ NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
};
static lm_info_vector
solib_target_parse_libraries (const char *library)
{
lm_info_vector result;
if (gdb_xml_parse_quick (_("target library list"), "library-list.dtd",
library_list_elements, library, &result) == 0)
{
/* Parsed successfully. */
return result;
}
result.clear ();
return result;
}
#endif
static struct so_list *
solib_target_current_sos (void)
{
struct so_list *new_solib, *start = NULL, *last = NULL;
/* Fetch the list of shared libraries. */
gdb::optional library_document
= target_read_stralloc (current_inferior ()->top_target (),
TARGET_OBJECT_LIBRARIES, NULL);
if (!library_document)
return NULL;
/* Parse the list. */
lm_info_vector library_list
= solib_target_parse_libraries (library_document->data ());
if (library_list.empty ())
return NULL;
/* Build a struct so_list for each entry on the list. */
for (auto &&info : library_list)
{
new_solib = XCNEW (struct so_list);
strncpy (new_solib->so_name, info->name.c_str (),
SO_NAME_MAX_PATH_SIZE - 1);
new_solib->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
strncpy (new_solib->so_original_name, info->name.c_str (),
SO_NAME_MAX_PATH_SIZE - 1);
new_solib->so_original_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
/* We no longer need this copy of the name. */
info->name.clear ();
new_solib->lm_info = info.release ();
/* Add it to the list. */
if (!start)
last = start = new_solib;
else
{
last->next = new_solib;
last = new_solib;
}
}
return start;
}
static void
solib_target_solib_create_inferior_hook (int from_tty)
{
/* Nothing needed. */
}
static void
solib_target_clear_solib (void)
{
/* Nothing needed. */
}
static void
solib_target_free_so (struct so_list *so)
{
lm_info_target *li = (lm_info_target *) so->lm_info;
gdb_assert (li->name.empty ());
delete li;
}
static void
solib_target_relocate_section_addresses (struct so_list *so,
struct target_section *sec)
{
CORE_ADDR offset;
lm_info_target *li = (lm_info_target *) so->lm_info;
/* Build the offset table only once per object file. We can not do
it any earlier, since we need to open the file first. */
if (li->offsets.empty ())
{
int num_sections = gdb_bfd_count_sections (so->abfd);
li->offsets.assign (num_sections, 0);
if (!li->section_bases.empty ())
{
int i;
asection *sect;
int num_alloc_sections = 0;
for (i = 0, sect = so->abfd->sections;
sect != NULL;
i++, sect = sect->next)
if ((bfd_section_flags (sect) & SEC_ALLOC))
num_alloc_sections++;
if (num_alloc_sections != li->section_bases.size ())
warning (_("\
Could not relocate shared library \"%s\": wrong number of ALLOC sections"),
so->so_name);
else
{
int bases_index = 0;
int found_range = 0;
so->addr_low = ~(CORE_ADDR) 0;
so->addr_high = 0;
for (i = 0, sect = so->abfd->sections;
sect != NULL;
i++, sect = sect->next)
{
if (!(bfd_section_flags (sect) & SEC_ALLOC))
continue;
if (bfd_section_size (sect) > 0)
{
CORE_ADDR low, high;
low = li->section_bases[i];
high = low + bfd_section_size (sect) - 1;
if (low < so->addr_low)
so->addr_low = low;
if (high > so->addr_high)
so->addr_high = high;
gdb_assert (so->addr_low <= so->addr_high);
found_range = 1;
}
li->offsets[i] = li->section_bases[bases_index];
bases_index++;
}
if (!found_range)
so->addr_low = so->addr_high = 0;
gdb_assert (so->addr_low <= so->addr_high);
}
}
else if (!li->segment_bases.empty ())
{
symfile_segment_data_up data
= get_symfile_segment_data (so->abfd);
if (data == NULL)
warning (_("\
Could not relocate shared library \"%s\": no segments"), so->so_name);
else
{
ULONGEST orig_delta;
int i;
if (!symfile_map_offsets_to_segments (so->abfd, data.get (),
li->offsets,
li->segment_bases.size (),
li->segment_bases.data ()))
warning (_("\
Could not relocate shared library \"%s\": bad offsets"), so->so_name);
/* Find the range of addresses to report for this library in
"info sharedlibrary". Report any consecutive segments
which were relocated as a single unit. */
gdb_assert (li->segment_bases.size () > 0);
orig_delta = li->segment_bases[0] - data->segments[0].base;
for (i = 1; i < data->segments.size (); i++)
{
/* If we have run out of offsets, assume all
remaining segments have the same offset. */
if (i >= li->segment_bases.size ())
continue;
/* If this segment does not have the same offset, do
not include it in the library's range. */
if (li->segment_bases[i] - data->segments[i].base
!= orig_delta)
break;
}
so->addr_low = li->segment_bases[0];
so->addr_high = (data->segments[i - 1].base
+ data->segments[i - 1].size
+ orig_delta);
gdb_assert (so->addr_low <= so->addr_high);
}
}
}
offset = li->offsets[gdb_bfd_section_index (sec->the_bfd_section->owner,
sec->the_bfd_section)];
sec->addr += offset;
sec->endaddr += offset;
}
static int
solib_target_open_symbol_file_object (int from_tty)
{
/* We can't locate the main symbol file based on the target's
knowledge; the user has to specify it. */
return 0;
}
static int
solib_target_in_dynsym_resolve_code (CORE_ADDR pc)
{
/* We don't have a range of addresses for the dynamic linker; there
may not be one in the program's address space. So only report
PLT entries (which may be import stubs). */
return in_plt_section (pc);
}
const struct target_so_ops solib_target_so_ops =
{
solib_target_relocate_section_addresses,
solib_target_free_so,
nullptr,
solib_target_clear_solib,
solib_target_solib_create_inferior_hook,
solib_target_current_sos,
solib_target_open_symbol_file_object,
solib_target_in_dynsym_resolve_code,
solib_bfd_open,
};