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_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;
CORE_ADDR 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;
}
