static void
dsbt_get_initial_loadmaps (void)
{
gdb_byte *buf;
struct dsbt_info *info = get_dsbt_info ();
if (0 >= target_read_alloc (¤t_target, TARGET_OBJECT_FDPIC,
"exec", (gdb_byte**) &buf))
{
info->exec_loadmap = NULL;
error (_("Error reading DSBT exec loadmap"));
}
info->exec_loadmap = decode_loadmap (buf);
if (solib_dsbt_debug)
dsbt_print_loadmap (info->exec_loadmap);
if (0 >= target_read_alloc (¤t_target, TARGET_OBJECT_FDPIC,
"interp", (gdb_byte**)&buf))
{
info->interp_loadmap = NULL;
error (_("Error reading DSBT interp loadmap"));
}
info->interp_loadmap = decode_loadmap (buf);
if (solib_dsbt_debug)
dsbt_print_loadmap (info->interp_loadmap);
}
static int
dsbt_in_dynsym_resolve_code (CORE_ADDR pc)
{
struct dsbt_info *info = get_dsbt_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));
}
static int
enable_break2 (void)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
int success = 0;
char **bkpt_namep;
asection *interp_sect;
struct dsbt_info *info = get_dsbt_info ();
if (exec_bfd == NULL)
return 0;
if (!target_has_execution)
return 0;
if (info->enable_break2_done)
return 1;
info->interp_text_sect_low = 0;
info->interp_text_sect_high = 0;
info->interp_plt_sect_low = 0;
info->interp_plt_sect_high = 0;
/* Find the .interp section; if not found, warn the user and drop
into the old breakpoint at symbol code. */
interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
if (interp_sect)
{
unsigned int interp_sect_size;
gdb_byte *buf;
bfd *tmp_bfd = NULL;
int status;
CORE_ADDR addr, interp_loadmap_addr;
gdb_byte addr_buf[TIC6X_PTR_SIZE];
struct int_elf32_dsbt_loadmap *ldm;
volatile struct gdb_exception ex;
/* Read the contents of the .interp section into a local buffer;
the contents specify the dynamic linker this program uses. */
interp_sect_size = bfd_section_size (exec_bfd, interp_sect);
buf = alloca (interp_sect_size);
bfd_get_section_contents (exec_bfd, interp_sect,
buf, 0, interp_sect_size);
/* 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. */
TRY_CATCH (ex, RETURN_MASK_ALL)
{
tmp_bfd = solib_bfd_open (buf);
}
if (tmp_bfd == NULL)
{
enable_break_failure_warning ();
return 0;
}
dsbt_get_initial_loadmaps ();
ldm = info->interp_loadmap;
/* Record the relocated start and end address of the dynamic linker
text and plt section for dsbt_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);
info->interp_text_sect_low
+= displacement_from_map (ldm, info->interp_text_sect_low);
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);
info->interp_plt_sect_low
+= displacement_from_map (ldm, info->interp_plt_sect_low);
info->interp_plt_sect_high =
info->interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
}
addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_addr");
if (addr == 0)
{
warning (_("Could not find symbol _dl_debug_addr in dynamic linker"));
enable_break_failure_warning ();
bfd_close (tmp_bfd);
return 0;
}
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_addr (prior to relocation) = %s\n",
hex_string_custom (addr, 8));
addr += displacement_from_map (ldm, addr);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_addr (after relocation) = %s\n",
hex_string_custom (addr, 8));
/* Fetch the address of the r_debug struct. */
if (target_read_memory (addr, addr_buf, sizeof addr_buf) != 0)
{
warning (_("Unable to fetch contents of _dl_debug_addr "
"(at address %s) from dynamic linker"),
hex_string_custom (addr, 8));
}
addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_addr[0..3] = %s\n",
hex_string_custom (addr, 8));
/* If it's zero, then the ldso hasn't initialized yet, and so
there are no shared libs yet loaded. */
if (addr == 0)
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: ldso not yet initialized\n");
/* Do not warn, but mark to run again. */
return 0;
}
/* Fetch the r_brk field. It's 8 bytes from the start of
_dl_debug_addr. */
if (target_read_memory (addr + 8, addr_buf, sizeof addr_buf) != 0)
{
warning (_("Unable to fetch _dl_debug_addr->r_brk "
"(at address %s) from dynamic linker"),
hex_string_custom (addr + 8, 8));
enable_break_failure_warning ();
bfd_close (tmp_bfd);
return 0;
}
addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);
/* We're done with the temporary bfd. */
bfd_close (tmp_bfd);
/* We're also done with the loadmap. */
xfree (ldm);
/* Remove all the solib event breakpoints. Their addresses
may have changed since the last time we ran the program. */
remove_solib_event_breakpoints ();
/* Now (finally!) create the solib breakpoint. */
create_solib_event_breakpoint (target_gdbarch, addr);
info->enable_break2_done = 1;
return 1;
}
static struct so_list *
dsbt_current_sos (void)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
CORE_ADDR lm_addr;
struct so_list *sos_head = NULL;
struct so_list **sos_next_ptr = &sos_head;
struct dsbt_info *info = get_dsbt_info ();
/* Make sure that the main executable has been relocated. This is
required in order to find the address of the global offset table,
which in turn is used to find the link map info. (See lm_base
for details.)
Note that the relocation of the main executable is also performed
by SOLIB_CREATE_INFERIOR_HOOK, however, in the case of core
files, this hook is called too late in order to be of benefit to
SOLIB_ADD. SOLIB_ADD eventually calls this function,
dsbt_current_sos, and also precedes the call to
SOLIB_CREATE_INFERIOR_HOOK. (See post_create_inferior in
infcmd.c.) */
if (info->main_executable_lm_info == 0 && core_bfd != NULL)
dsbt_relocate_main_executable ();
/* Locate the address of the first link map struct. */
lm_addr = lm_base ();
/* We have at least one link map entry. Fetch the the lot of them,
building the solist chain. */
while (lm_addr)
{
struct ext_link_map lm_buf;
ext_Elf32_Word indexword;
CORE_ADDR map_addr;
int dsbt_index;
int ret;
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"current_sos: reading link_map entry at %s\n",
hex_string_custom (lm_addr, 8));
ret = target_read_memory (lm_addr, (gdb_byte *) &lm_buf, sizeof (lm_buf));
if (ret)
{
warning (_("dsbt_current_sos: Unable to read link map entry."
" Shared object chain may be incomplete."));
break;
}
/* Fetch the load map address. */
map_addr = extract_unsigned_integer (lm_buf.l_addr.map,
sizeof lm_buf.l_addr.map,
byte_order);
ret = target_read_memory (map_addr + 12, (gdb_byte *) &indexword,
sizeof indexword);
if (ret)
{
warning (_("dsbt_current_sos: Unable to read dsbt index."
" Shared object chain may be incomplete."));
break;
}
dsbt_index = extract_unsigned_integer (indexword, sizeof indexword,
byte_order);
/* If the DSBT index is zero, then we're looking at the entry
for the main executable. By convention, we don't include
this in the list of shared objects. */
if (dsbt_index != 0)
{
int errcode;
char *name_buf;
struct int_elf32_dsbt_loadmap *loadmap;
struct so_list *sop;
CORE_ADDR addr;
loadmap = fetch_loadmap (map_addr);
if (loadmap == NULL)
{
warning (_("dsbt_current_sos: Unable to fetch load map."
" Shared object chain may be incomplete."));
break;
}
sop = xcalloc (1, sizeof (struct so_list));
sop->lm_info = xcalloc (1, sizeof (struct lm_info));
sop->lm_info->map = loadmap;
/* Fetch the name. */
addr = extract_unsigned_integer (lm_buf.l_name,
sizeof (lm_buf.l_name),
byte_order);
target_read_string (addr, &name_buf, SO_NAME_MAX_PATH_SIZE - 1,
&errcode);
if (errcode != 0)
warning (_("Can't read pathname for link map entry: %s."),
safe_strerror (errcode));
else
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog, "current_sos: name = %s\n",
name_buf);
strncpy (sop->so_name, name_buf, SO_NAME_MAX_PATH_SIZE - 1);
sop->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
xfree (name_buf);
strcpy (sop->so_original_name, sop->so_name);
}
*sos_next_ptr = sop;
sos_next_ptr = &sop->next;
}
else
{
info->main_lm_addr = lm_addr;
}
lm_addr = extract_unsigned_integer (lm_buf.l_next,
sizeof (lm_buf.l_next), byte_order);
}
enable_break2 ();
return sos_head;
}
static CORE_ADDR
lm_base (void)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
struct minimal_symbol *got_sym;
CORE_ADDR addr;
gdb_byte buf[TIC6X_PTR_SIZE];
struct dsbt_info *info = get_dsbt_info ();
/* One of our assumptions is that the main executable has been relocated.
Bail out if this has not happened. (Note that post_create_inferior
in infcmd.c will call solib_add prior to solib_create_inferior_hook.
If we allow this to happen, lm_base_cache will be initialized with
a bogus value. */
if (info->main_executable_lm_info == 0)
return 0;
/* If we already have a cached value, return it. */
if (info->lm_base_cache)
return info->lm_base_cache;
got_sym = lookup_minimal_symbol ("_GLOBAL_OFFSET_TABLE_", NULL,
symfile_objfile);
if (got_sym != 0)
{
addr = SYMBOL_VALUE_ADDRESS (got_sym);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"lm_base: get addr %x by _GLOBAL_OFFSET_TABLE_.\n",
(unsigned int) addr);
}
else if (scan_dyntag (DT_PLTGOT, exec_bfd, &addr))
{
struct int_elf32_dsbt_loadmap *ldm;
dsbt_get_initial_loadmaps ();
ldm = info->exec_loadmap;
addr += displacement_from_map (ldm, addr);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"lm_base: get addr %x by DT_PLTGOT.\n",
(unsigned int) addr);
}
else
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"lm_base: _GLOBAL_OFFSET_TABLE_ not found.\n");
return 0;
}
addr += GOT_MODULE_OFFSET;
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"lm_base: _GLOBAL_OFFSET_TABLE_ + %d = %s\n",
GOT_MODULE_OFFSET, hex_string_custom (addr, 8));
if (target_read_memory (addr, buf, sizeof buf) != 0)
return 0;
info->lm_base_cache = extract_unsigned_integer (buf, sizeof buf, byte_order);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"lm_base: lm_base_cache = %s\n",
hex_string_custom (info->lm_base_cache, 8));
return info->lm_base_cache;
}
static int
enable_break (void)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
asection *interp_sect;
struct dsbt_info *info;
if (exec_bfd == NULL)
return 0;
if (!target_has_execution)
return 0;
info = get_dsbt_info ();
info->interp_text_sect_low = 0;
info->interp_text_sect_high = 0;
info->interp_plt_sect_low = 0;
info->interp_plt_sect_high = 0;
/* Find the .interp section; if not found, warn the user and drop
into the old breakpoint at symbol code. */
interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
if (interp_sect)
{
unsigned int interp_sect_size;
char *buf;
bfd *tmp_bfd = NULL;
CORE_ADDR addr;
gdb_byte addr_buf[TIC6X_PTR_SIZE];
struct int_elf32_dsbt_loadmap *ldm;
volatile struct gdb_exception ex;
int ret;
/* Read the contents of the .interp section into a local buffer;
the contents specify the dynamic linker this program uses. */
interp_sect_size = bfd_section_size (exec_bfd, interp_sect);
buf = alloca (interp_sect_size);
bfd_get_section_contents (exec_bfd, interp_sect,
buf, 0, interp_sect_size);
/* 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. */
TRY_CATCH (ex, RETURN_MASK_ALL)
{
tmp_bfd = solib_bfd_open (buf);
}
if (tmp_bfd == NULL)
{
enable_break_failure_warning ();
return 0;
}
dsbt_get_initial_loadmaps ();
ldm = info->interp_loadmap;
/* Record the relocated start and end address of the dynamic linker
text and plt section for dsbt_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);
info->interp_text_sect_low
+= displacement_from_map (ldm, info->interp_text_sect_low);
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);
info->interp_plt_sect_low
+= displacement_from_map (ldm, info->interp_plt_sect_low);
info->interp_plt_sect_high =
info->interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
}
addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_state");
if (addr != 0)
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_state (prior to relocation) = %s\n",
hex_string_custom (addr, 8));
addr += displacement_from_map (ldm, addr);
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_state (after relocation) = %s\n",
hex_string_custom (addr, 8));
/* Now (finally!) create the solib breakpoint. */
create_solib_event_breakpoint (target_gdbarch (), addr);
ret = 1;
}
else
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
"enable_break: _dl_debug_state is not found\n");
ret = 0;
}
/* We're done with the temporary bfd. */
gdb_bfd_unref (tmp_bfd);
/* We're also done with the loadmap. */
xfree (ldm);
return ret;
}
