/* Handle SunOS and SVR4 shared libraries for GDB, the GNU Debugger.
- Copyright 1990, 1991, 1992 Free Software Foundation, Inc.
+ Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996
+ Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
#include <sys/types.h>
#include <signal.h>
-#include <string.h>
-#include <link.h>
+#include "gdb_string.h"
#include <sys/param.h>
#include <fcntl.h>
+#include <unistd.h>
#ifndef SVR4_SHARED_LIBS
/* SunOS shared libs need the nlist structure. */
#include <a.out.h>
+#else
+#include "elf/external.h"
#endif
+#include <link.h>
+
#include "symtab.h"
#include "bfd.h"
#include "symfile.h"
#include "command.h"
#include "target.h"
#include "frame.h"
-#include "regex.h"
+#include "gnu-regex.h"
#include "inferior.h"
+#include "environ.h"
#include "language.h"
+#include "gdbcmd.h"
+
+#define MAX_PATH_SIZE 512 /* FIXME: Should be dynamic */
+
+/* On SVR4 systems, a list of symbols in the dynamic linker where
+ GDB can try to place a breakpoint to monitor shared library
+ events.
-#define MAX_PATH_SIZE 256 /* FIXME: Should be dynamic */
+ If none of these symbols are found, or other errors occur, then
+ SVR4 systems will fall back to using a symbol as the "startup
+ mapping complete" breakpoint address. */
-/* On SVR4 systems, for the initial implementation, use some runtime startup
- symbol as the "startup mapping complete" breakpoint address. The models
- for SunOS and SVR4 dynamic linking debugger support are different in that
- SunOS hits one breakpoint when all mapping is complete while using the SVR4
- debugger support takes two breakpoint hits for each file mapped, and
- there is no way to know when the "last" one is hit. Both these
- mechanisms should be tied to a "breakpoint service routine" that
- gets automatically executed whenever one of the breakpoints indicating
- a change in mapping is hit. This is a future enhancement. (FIXME) */
+#ifdef SVR4_SHARED_LIBS
+static char *solib_break_names[] = {
+ "r_debug_state",
+ "_dl_debug_state",
+ NULL
+};
+#endif
#define BKPT_AT_SYMBOL 1
/* Symbols which are used to locate the base of the link map structures. */
+#ifndef SVR4_SHARED_LIBS
static char *debug_base_symbols[] = {
-#ifdef SVR4_SHARED_LIBS
- "_r_debug", /* Most SVR4 systems, Solaris 2.1, 2.2 */
- "r_debug", /* Solaris 2.3 */
-#else
- "_DYNAMIC", /* SunOS */
+ "_DYNAMIC",
+ "_DYNAMIC__MGC",
+ NULL
+};
#endif
+
+static char *main_name_list[] = {
+ "main_$main",
NULL
};
#ifdef SVR4_SHARED_LIBS
-static int
-look_for_base PARAMS ((int, CORE_ADDR));
-
static CORE_ADDR
-bfd_lookup_symbol PARAMS ((bfd *, char *));
+elf_locate_base PARAMS ((void));
#else
static void
-solib_add_common_symbols PARAMS ((struct rtc_symb *, struct objfile *));
+allocate_rt_common_objfile PARAMS ((void));
+
+static void
+solib_add_common_symbols PARAMS ((struct rtc_symb *));
#endif
filename = tilde_expand (so -> so_name);
old_chain = make_cleanup (free, filename);
- scratch_chan = openp (getenv ("PATH"), 1, filename, O_RDONLY, 0,
- &scratch_pathname);
+ scratch_chan = openp (get_in_environ (inferior_environ, "PATH"),
+ 1, filename, O_RDONLY, 0, &scratch_pathname);
if (scratch_chan < 0)
{
- scratch_chan = openp (getenv ("LD_LIBRARY_PATH"), 1, filename,
- O_RDONLY, 0, &scratch_pathname);
+ scratch_chan = openp (get_in_environ
+ (inferior_environ, "LD_LIBRARY_PATH"),
+ 1, filename, O_RDONLY, 0, &scratch_pathname);
}
if (scratch_chan < 0)
{
so -> abfd = abfd;
abfd -> cacheable = true;
+ /* copy full path name into so_name, so that later symbol_file_add can find
+ it */
+ if (strlen (scratch_pathname) >= MAX_PATH_SIZE)
+ error ("Full path name length of shared library exceeds MAX_PATH_SIZE in so_list structure.");
+ strcpy (so->so_name, scratch_pathname);
+
if (!bfd_check_format (abfd, bfd_object))
{
error ("\"%s\": not in executable format: %s.",
if (build_section_table (abfd, &so -> sections, &so -> sections_end))
{
error ("Can't find the file sections in `%s': %s",
- bfd_get_filename (exec_bfd), bfd_errmsg (bfd_get_error ()));
+ bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
}
for (p = so -> sections; p < so -> sections_end; p++)
p -> addr += (CORE_ADDR) LM_ADDR (so);
p -> endaddr += (CORE_ADDR) LM_ADDR (so);
so -> lmend = (CORE_ADDR) max (p -> endaddr, so -> lmend);
- if (STREQ (p -> sec_ptr -> name, ".text"))
+ if (STREQ (p -> the_bfd_section -> name, ".text"))
{
so -> textsection = p;
}
do_cleanups (old_chain);
}
-/* Read all dynamically loaded common symbol definitions from the inferior
- and add them to the minimal symbol table for the shared library objfile. */
-
#ifndef SVR4_SHARED_LIBS
-/* In GDB 4.9 this routine was a real performance hog. According to
- some gprof data which mtranle@paris.IntelliCorp.COM (Minh Tran-Le)
- sent, almost all the time spend in solib_add (up to 20 minutes with
- 35 shared libraries) was spent here, with 5/6 in
- lookup_minimal_symbol and 1/6 in read_memory.
+/* Allocate the runtime common object file. */
+
+static void
+allocate_rt_common_objfile ()
+{
+ struct objfile *objfile;
+ struct objfile *last_one;
+
+ objfile = (struct objfile *) xmalloc (sizeof (struct objfile));
+ memset (objfile, 0, sizeof (struct objfile));
+ objfile -> md = NULL;
+ obstack_specify_allocation (&objfile -> psymbol_cache.cache, 0, 0,
+ xmalloc, free);
+ obstack_specify_allocation (&objfile -> psymbol_obstack, 0, 0, xmalloc,
+ free);
+ obstack_specify_allocation (&objfile -> symbol_obstack, 0, 0, xmalloc,
+ free);
+ obstack_specify_allocation (&objfile -> type_obstack, 0, 0, xmalloc,
+ free);
+ objfile -> name = mstrsave (objfile -> md, "rt_common");
+
+ /* Add this file onto the tail of the linked list of other such files. */
+
+ objfile -> next = NULL;
+ if (object_files == NULL)
+ object_files = objfile;
+ else
+ {
+ for (last_one = object_files;
+ last_one -> next;
+ last_one = last_one -> next);
+ last_one -> next = objfile;
+ }
+
+ rt_common_objfile = objfile;
+}
- To fix this, we moved the call to special_symbol_handling out of the
- loop in solib_add, so this only gets called once, rather than once
- for every shared library, and also removed the call to lookup_minimal_symbol
- in this routine. */
+/* Read all dynamically loaded common symbol definitions from the inferior
+ and put them into the minimal symbol table for the runtime common
+ objfile. */
static void
-solib_add_common_symbols (rtc_symp, objfile)
+solib_add_common_symbols (rtc_symp)
struct rtc_symb *rtc_symp;
- struct objfile *objfile;
{
struct rtc_symb inferior_rtc_symb;
struct nlist inferior_rtc_nlist;
char *name;
char *origname;
+ /* Remove any runtime common symbols from previous runs. */
+
+ if (rt_common_objfile != NULL && rt_common_objfile -> minimal_symbol_count)
+ {
+ obstack_free (&rt_common_objfile -> symbol_obstack, 0);
+ obstack_specify_allocation (&rt_common_objfile -> symbol_obstack, 0, 0,
+ xmalloc, free);
+ rt_common_objfile -> minimal_symbol_count = 0;
+ rt_common_objfile -> msymbols = NULL;
+ }
+
init_minimal_symbol_collection ();
make_cleanup (discard_minimal_symbols, 0);
origname = name = xmalloc (len);
read_memory ((CORE_ADDR) inferior_rtc_nlist.n_un.n_name, name, len);
- /* Don't enter the symbol twice if the target is re-run. */
-
- if (name[0] == bfd_get_symbol_leading_char (objfile->obfd))
- {
- name++;
- }
+ /* Allocate the runtime common objfile if necessary. */
+ if (rt_common_objfile == NULL)
+ allocate_rt_common_objfile ();
-#if 0
- /* I think this is unnecessary, GDB can probably deal with
- duplicate minimal symbols, more or less. And the duplication
- which used to happen because this was called for each shared
- library is gone now that we are just called once. */
- /* FIXME: Do we really want to exclude symbols which happen
- to match symbols for other locations in the inferior's
- address space, even when they are in different linkage units? */
- if (lookup_minimal_symbol (name, (struct objfile *) NULL) == NULL)
-#endif
- {
- name = obsavestring (name, strlen (name),
- &objfile -> symbol_obstack);
- prim_record_minimal_symbol (name, inferior_rtc_nlist.n_value,
- mst_bss, objfile);
- }
+ name = obsavestring (name, strlen (name),
+ &rt_common_objfile -> symbol_obstack);
+ prim_record_minimal_symbol (name, inferior_rtc_nlist.n_value,
+ mst_bss, rt_common_objfile);
free (origname);
}
rtc_symp = inferior_rtc_symb.rtc_next;
}
/* Install any minimal symbols that have been collected as the current
- minimal symbols for this objfile. */
+ minimal symbols for the runtime common objfile. */
- install_minimal_symbols (objfile);
+ install_minimal_symbols (rt_common_objfile);
}
#endif /* SVR4_SHARED_LIBS */
+
#ifdef SVR4_SHARED_LIBS
+#ifdef HANDLE_SVR4_EXEC_EMULATORS
+
+/*
+ Solaris BCP (the part of Solaris which allows it to run SunOS4
+ a.out files) throws in another wrinkle. Solaris does not fill
+ in the usual a.out link map structures when running BCP programs,
+ the only way to get at them is via groping around in the dynamic
+ linker.
+ The dynamic linker and it's structures are located in the shared
+ C library, which gets run as the executable's "interpreter" by
+ the kernel.
+
+ Note that we can assume nothing about the process state at the time
+ we need to find these structures. We may be stopped on the first
+ instruction of the interpreter (C shared library), the first
+ instruction of the executable itself, or somewhere else entirely
+ (if we attached to the process for example).
+*/
+
+static char *debug_base_symbols[] = {
+ "r_debug", /* Solaris 2.3 */
+ "_r_debug", /* Solaris 2.1, 2.2 */
+ NULL
+};
+
+static int
+look_for_base PARAMS ((int, CORE_ADDR));
+
+static CORE_ADDR
+bfd_lookup_symbol PARAMS ((bfd *, char *));
+
/*
LOCAL FUNCTION
Note that 0 is specifically allowed as an error return (no
such symbol).
-
- FIXME: See if there is a less "expensive" way of doing this.
- Also see if there is already another bfd or gdb function
- that specifically does this, and if so, use it.
*/
static CORE_ADDR
struct cleanup *back_to;
CORE_ADDR symaddr = 0;
- storage_needed = get_symtab_upper_bound (abfd);
+ storage_needed = bfd_get_symtab_upper_bound (abfd);
if (storage_needed > 0)
{
CORE_ADDR baseaddr;
{
bfd *interp_bfd;
- CORE_ADDR address;
+ CORE_ADDR address = 0;
char **symbolp;
/* If the fd is -1, then there is no file that corresponds to this
mapped memory segment, so skip it. Also, if the fd corresponds
to the exec file, skip it as well. */
- if ((fd == -1) || fdmatch (fileno ((GDB_FILE *)(exec_bfd -> iostream)), fd))
+ if (fd == -1
+ || (exec_bfd != NULL
+ && fdmatch (fileno ((GDB_FILE *)(exec_bfd -> iostream)), fd)))
{
return (0);
}
}
if (!bfd_check_format (interp_bfd, bfd_object))
{
+ /* FIXME-leak: on failure, might not free all memory associated with
+ interp_bfd. */
bfd_close (interp_bfd);
return (0);
}
}
if (address == 0)
{
+ /* FIXME-leak: on failure, might not free all memory associated with
+ interp_bfd. */
bfd_close (interp_bfd);
return (0);
}
address += baseaddr;
}
debug_base = address;
+ /* FIXME-leak: on failure, might not free all memory associated with
+ interp_bfd. */
bfd_close (interp_bfd);
return (1);
}
+#endif /* HANDLE_SVR4_EXEC_EMULATORS */
+
+/*
+
+LOCAL FUNCTION
+
+ elf_locate_base -- locate the base address of dynamic linker structs
+ for SVR4 elf targets.
+
+SYNOPSIS
+ CORE_ADDR elf_locate_base (void)
+
+DESCRIPTION
+
+ 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 ()
+{
+ sec_ptr dyninfo_sect;
+ int dyninfo_sect_size;
+ CORE_ADDR dyninfo_addr;
+ char *buf;
+ char *bufend;
+
+ /* Find the start address of the .dynamic section. */
+ dyninfo_sect = bfd_get_section_by_name (exec_bfd, ".dynamic");
+ if (dyninfo_sect == NULL)
+ return 0;
+ dyninfo_addr = bfd_section_vma (exec_bfd, dyninfo_sect);
+
+ /* Read in .dynamic section, silently ignore errors. */
+ dyninfo_sect_size = bfd_section_size (exec_bfd, dyninfo_sect);
+ buf = alloca (dyninfo_sect_size);
+ if (target_read_memory (dyninfo_addr, buf, dyninfo_sect_size))
+ return 0;
+
+ /* Find the DT_DEBUG entry in the the .dynamic section.
+ For mips elf we look for DT_MIPS_RLD_MAP, mips elf apparently has
+ no DT_DEBUG entries. */
+ /* FIXME: In lack of a 64 bit ELF ABI the following code assumes
+ a 32 bit ELF ABI target. */
+ for (bufend = buf + dyninfo_sect_size;
+ buf < bufend;
+ buf += sizeof (Elf32_External_Dyn))
+ {
+ Elf32_External_Dyn *x_dynp = (Elf32_External_Dyn *)buf;
+ long dyn_tag;
+ CORE_ADDR dyn_ptr;
+
+ dyn_tag = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_tag);
+ if (dyn_tag == DT_NULL)
+ break;
+ else if (dyn_tag == DT_DEBUG)
+ {
+ dyn_ptr = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr);
+ return dyn_ptr;
+ }
+#ifdef DT_MIPS_RLD_MAP
+ else if (dyn_tag == DT_MIPS_RLD_MAP)
+ {
+ char pbuf[TARGET_PTR_BIT / HOST_CHAR_BIT];
+
+ /* DT_MIPS_RLD_MAP contains a pointer to the address
+ of the dynamic link structure. */
+ dyn_ptr = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr);
+ if (target_read_memory (dyn_ptr, pbuf, sizeof (pbuf)))
+ return 0;
+ return extract_unsigned_integer (pbuf, sizeof (pbuf));
+ }
#endif
+ }
+
+ /* DT_DEBUG entry not found. */
+ return 0;
+}
+
+#endif /* SVR4_SHARED_LIBS */
/*
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 much more complicated because the dynamic linker
- and it's structures are located in the shared C library, which gets
- run as the executable's "interpreter" by the kernel. We have to go
+ 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.
- Note that we can assume nothing about the process state at the time
- we need to find this address. We may be stopped on the first instruc-
- tion of the interpreter (C shared library), the first instruction of
- the executable itself, or somewhere else entirely (if we attached
- to the process for example).
-
*/
static CORE_ADDR
for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++)
{
- msymbol = lookup_minimal_symbol (*symbolp, symfile_objfile);
+ msymbol = lookup_minimal_symbol (*symbolp, NULL, symfile_objfile);
if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
{
address = SYMBOL_VALUE_ADDRESS (msymbol);
/* 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, ask the /proc support interface to iterate
- over the list of mapped address segments, calling look_for_base() for
- each segment. When we are done, we will have either found the base
- address or not. */
+ we have no cached address, try to locate it in the dynamic info
+ section for ELF executables. */
if (debug_base == 0)
{
- proc_iterate_over_mappings (look_for_base);
+ if (exec_bfd != NULL
+ && bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour)
+ debug_base = elf_locate_base ();
+#ifdef HANDLE_SVR4_EXEC_EMULATORS
+ /* Try it the hard way for emulated executables. */
+ else if (inferior_pid != 0)
+ proc_iterate_over_mappings (look_for_base);
+#endif
}
return (debug_base);
{
register struct so_list *so = (struct so_list *) arg; /* catch_errs bogon */
- so -> objfile = symbol_file_add (so -> so_name, so -> from_tty,
- (unsigned int) so -> textsection -> addr,
- 0, 0, 0);
+ so -> objfile =
+ symbol_file_add (so -> so_name, so -> from_tty,
+ (so->textsection == NULL
+ ? 0
+ : (unsigned int) so -> textsection -> addr),
+ 0, 0, 0);
return (1);
}
+/* This function will check the so name to see if matches the main list.
+ In some system the main object is in the list, which we want to exclude */
+
+static int match_main (soname)
+ char *soname;
+{
+ char **mainp;
+
+ for (mainp = main_name_list; *mainp != NULL; mainp++)
+ {
+ if (strcmp (soname, *mainp) == 0)
+ return (1);
+ }
+
+ return (0);
+}
+
/*
GLOBAL FUNCTION
error ("Invalid regexp: %s", re_err);
}
- /* Getting new symbols may change our opinion about what is
- frameless. */
- reinit_frame_cache ();
-
- while ((so = find_solib (so)) != NULL)
- {
- if (so -> so_name[0] && re_exec (so -> so_name))
- {
- so -> from_tty = from_tty;
- if (so -> symbols_loaded)
- {
- if (from_tty)
- {
- printf_unfiltered ("Symbols already loaded for %s\n", so -> so_name);
- }
- }
- else if (catch_errors
- (symbol_add_stub, (char *) so,
- "Error while reading shared library symbols:\n",
- RETURN_MASK_ALL))
- {
- so_last = so;
- so -> symbols_loaded = 1;
- }
- }
- }
-
- /* Now add the shared library sections to the section table of the
+ /* Add the shared library sections to the section table of the
specified target, if any. */
if (target)
{
count = 0;
while ((so = find_solib (so)) != NULL)
{
- if (so -> so_name[0])
+ if (so -> so_name[0] && !match_main (so -> so_name))
{
count += so -> sections_end - so -> sections;
}
if (count)
{
+ int update_coreops;
+
+ /* We must update the to_sections field in the core_ops structure
+ here, otherwise we dereference a potential dangling pointer
+ for each call to target_read/write_memory within this routine. */
+ update_coreops = core_ops.to_sections == target->to_sections;
+
/* Reallocate the target's section table including the new size. */
if (target -> to_sections)
{
}
target -> to_sections_end = target -> to_sections + (count + old);
+ /* Update the to_sections field in the core_ops structure
+ if needed. */
+ if (update_coreops)
+ {
+ core_ops.to_sections = target->to_sections;
+ core_ops.to_sections_end = target->to_sections_end;
+ }
+
/* Add these section table entries to the target's table. */
while ((so = find_solib (so)) != NULL)
{
}
}
}
+
+ /* Now add the symbol files. */
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so -> so_name[0] && re_exec (so -> so_name) &&
+ !match_main (so -> so_name))
+ {
+ so -> from_tty = from_tty;
+ if (so -> symbols_loaded)
+ {
+ if (from_tty)
+ {
+ printf_unfiltered ("Symbols already loaded for %s\n", so -> so_name);
+ }
+ }
+ else if (catch_errors
+ (symbol_add_stub, (char *) so,
+ "Error while reading shared library symbols:\n",
+ RETURN_MASK_ALL))
+ {
+ so_last = so;
+ so -> symbols_loaded = 1;
+ }
+ }
+ }
- /* Calling this once at the end means that we put all the minimal
- symbols for commons into the objfile for the last shared library.
- Since they are in common, this should not be a problem. If we
- delete the objfile with the minimal symbols, we can put all the
- symbols into a new objfile (and will on the next call to solib_add).
-
- An alternate approach would be to create an objfile just for
- common minsyms, thus not needing any objfile argument to
- solib_add_common_symbols. */
+ /* Getting new symbols may change our opinion about what is
+ frameless. */
+ if (so_last)
+ reinit_frame_cache ();
if (so_last)
special_symbol_handling (so_last);
SYNOPSIS
- int solib_address (CORE_ADDR address)
+ char * solib_address (CORE_ADDR address)
DESCRIPTION
mapped in.
*/
-int
+char *
solib_address (address)
CORE_ADDR address;
{
{
if ((address >= (CORE_ADDR) LM_ADDR (so)) &&
(address < (CORE_ADDR) so -> lmend))
- {
- return (1);
- }
+ return (so->so_name);
}
}
return (0);
if (so_list_head -> abfd)
{
bfd_filename = bfd_get_filename (so_list_head -> abfd);
- bfd_close (so_list_head -> abfd);
+ if (!bfd_close (so_list_head -> abfd))
+ warning ("cannot close \"%s\": %s",
+ bfd_filename, bfd_errmsg (bfd_get_error ()));
}
else
/* This happens for the executable on SVR4. */
#ifdef BKPT_AT_SYMBOL
struct minimal_symbol *msymbol;
+ struct objfile *objfile;
char **bkpt_namep;
CORE_ADDR bkpt_addr;
+ asection *interp_sect;
+
+ /* First, remove all the solib event breakpoints. Their addresses
+ may have changed since the last time we ran the program. */
+ remove_solib_event_breakpoints ();
+
+#ifdef SVR4_SHARED_LIBS
+ /* 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;
+ CORE_ADDR load_addr;
+ bfd *tmp_bfd;
+ asection *lowest_sect;
+
+ /* 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.
+
+ 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 Linux). Therefore, we have to try an alternate
+ mechanism to find the dynamic linker's base address. */
+ tmp_bfd = bfd_openr (buf, gnutarget);
+ if (tmp_bfd == NULL)
+ goto bkpt_at_symbol;
+
+ /* Make sure the dynamic linker's really a useful object. */
+ if (!bfd_check_format (tmp_bfd, bfd_object))
+ {
+ warning ("Unable to grok dynamic linker %s as an object file", buf);
+ bfd_close (tmp_bfd);
+ goto bkpt_at_symbol;
+ }
+
+ /* We find the dynamic linker's base address by examining the
+ current pc (which point at the entry point for the dynamic
+ linker) and subtracting the offset of the entry point. */
+ load_addr = read_pc () - tmp_bfd->start_address;
+
+ /* load_addr now has the base address of the dynamic linker;
+ however, due to severe braindamage in syms_from_objfile
+ we need to add the address of the .text section, or the
+ lowest section of .text doesn't exist to work around the
+ braindamage. Gross. */
+ lowest_sect = bfd_get_section_by_name (tmp_bfd, ".text");
+ if (lowest_sect == NULL)
+ bfd_map_over_sections (tmp_bfd, find_lowest_section,
+ (PTR) &lowest_sect);
+
+ if (lowest_sect == NULL)
+ {
+ warning ("Unable to find base address for dynamic linker %s\n", buf);
+ bfd_close (tmp_bfd);
+ goto bkpt_at_symbol;
+ }
+
+ load_addr += bfd_section_vma (tmp_bfd, lowest_sect);
+
+ /* We're done with the temporary bfd. */
+ bfd_close (tmp_bfd);
+
+ /* Now make GDB aware of the symbols in the dynamic linker. Some
+ might complain about namespace pollution, but as a developer I've
+ often wanted these symbols available from within the debugger. */
+ objfile = symbol_file_add (buf, 0, load_addr, 0, 0, 1);
+
+ /* Now try to set a breakpoint in the dynamic linker. */
+ for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++)
+ {
+ msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, objfile);
+ if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
+ {
+ create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol));
+ 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:
+ warning ("Unable to find dynamic linker breakpoint function.");
+ warning ("GDB will be unable to debug shared library initializers");
+ warning ("and track explicitly loaded dynamic code.");
+ }
+#endif
/* Scan through the list of symbols, trying to look up the symbol and
set a breakpoint there. Terminate loop when we/if we succeed. */
breakpoint_addr = 0;
for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++)
{
- msymbol = lookup_minimal_symbol (*bkpt_namep, symfile_objfile);
+ msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile);
if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
{
- bkpt_addr = SYMBOL_VALUE_ADDRESS (msymbol);
- if (target_insert_breakpoint (bkpt_addr, shadow_contents) == 0)
- {
- breakpoint_addr = bkpt_addr;
- success = 1;
- break;
- }
+ create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol));
+ return 1;
}
}
-#else /* !BKPT_AT_SYMBOL */
-
- struct symtab_and_line sal;
-
- /* Read the debugger interface structure directly. */
-
- read_memory (debug_base, (char *) &debug_copy, sizeof (debug_copy));
-
- /* Set breakpoint at the debugger interface stub routine that will
- be called just prior to each mapping change and again after the
- mapping change is complete. Set up the (nonexistent) handler to
- deal with hitting these breakpoints. (FIXME). */
-
- warning ("'%s': line %d: missing SVR4 support code", __FILE__, __LINE__);
- success = 1;
+ /* Nothing good happened. */
+ return 0;
#endif /* BKPT_AT_SYMBOL */
return;
}
- /* Now run the target. It will eventually hit the breakpoint, at
+#ifndef BKPT_AT_SYMBOL
+ /* Only SunOS 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. */
warning ("shared library handler failed to disable breakpoint");
}
- solib_add ((char *) 0, 0, (struct target_ops *) 0);
+ if (auto_solib_add)
+ solib_add ((char *) 0, 0, (struct target_ops *) 0);
+#endif
}
/*
way, we are called to do any system specific symbol handling that
is needed.
- For Suns, this consists of grunging around in the dynamic linkers
- structures to find symbol definitions for "common" symbols and
- adding them to the minimal symbol table for the corresponding
+ For SunOS4, this consists of grunging around in the dynamic
+ linkers structures to find symbol definitions for "common" symbols
+ and adding them to the minimal symbol table for the runtime common
objfile.
*/
if (debug_copy.ldd_cp)
{
- solib_add_common_symbols (debug_copy.ldd_cp, so -> objfile);
+ solib_add_common_symbols (debug_copy.ldd_cp);
}
#endif /* !SVR4_SHARED_LIBS */
"Load shared object library symbols for files matching REGEXP.");
add_info ("sharedlibrary", info_sharedlibrary_command,
"Status of loaded shared object libraries.");
+
+ add_show_from_set
+ (add_set_cmd ("auto-solib-add", class_support, var_zinteger,
+ (char *) &auto_solib_add,
+ "Set autoloading of shared library symbols.\n\
+If nonzero, symbols from all shared object libraries will be loaded\n\
+automatically when the inferior begins execution or when the dynamic linker\n\
+informs gdb that a new library has been loaded. Otherwise, symbols\n\
+must be loaded manually, using `sharedlibrary'.",
+ &setlist),
+ &showlist);
}
projects / binutils-gdb.git / blobdiff