-/* Copyright (C) 1990 Free Software Foundation, Inc.
-
+/* Handle SunOS and SVR4 shared libraries for GDB, the GNU Debugger.
+ Copyright 1990, 1991, 1992, 1993, 1994, 1995
+ Free Software Foundation, Inc.
+
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
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"
-/*
-** symbol definitions
-*/
#include <sys/types.h>
-#include <string.h>
-#include <link.h>
+#include <signal.h>
+#include "gdb_string.h"
#include <sys/param.h>
#include <fcntl.h>
-#include <stdio.h>
-#include "defs.h"
-#include "param.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 "objfiles.h"
#include "gdbcore.h"
#include "command.h"
#include "target.h"
#include "frame.h"
#include "regex.h"
#include "inferior.h"
+#include "environ.h"
+#include "language.h"
+#include "gdbcmd.h"
-extern char *getenv();
+#define MAX_PATH_SIZE 512 /* FIXME: Should be dynamic */
+
+/* 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) */
+
+#define BKPT_AT_SYMBOL 1
+
+#if defined (BKPT_AT_SYMBOL) && defined (SVR4_SHARED_LIBS)
+static char *bkpt_names[] = {
+#ifdef SOLIB_BKPT_NAME
+ SOLIB_BKPT_NAME, /* Prefer configured name if it exists. */
+#endif
+ "_start",
+ "main",
+ NULL
+};
+#endif
+
+/* Symbols which are used to locate the base of the link map structures. */
+
+#ifndef SVR4_SHARED_LIBS
+static char *debug_base_symbols[] = {
+ "_DYNAMIC",
+ "_DYNAMIC__MGC",
+ NULL
+};
+#endif
+
+static char *main_name_list[] = {
+ "main_$main",
+ NULL
+};
+
+/* local data declarations */
+
+/* If true, then shared library symbols will be added automatically
+ when the inferior is created. This is almost always what users
+ will want to have happen; but for very large programs, the startup
+ time will be excessive, and so if this is a problem, the user can
+ clear this flag and then add the shared library symbols as needed.
+ Note that there is a potential for confusion, since if the shared
+ library symbols are not loaded, commands like "info fun" will *not*
+ report all the functions that are actually present. */
+
+int auto_solib_add_at_startup = 1;
+
+#ifndef SVR4_SHARED_LIBS
+
+#define LM_ADDR(so) ((so) -> lm.lm_addr)
+#define LM_NEXT(so) ((so) -> lm.lm_next)
+#define LM_NAME(so) ((so) -> lm.lm_name)
+/* Test for first link map entry; first entry is a shared library. */
+#define IGNORE_FIRST_LINK_MAP_ENTRY(x) (0)
+static struct link_dynamic dynamic_copy;
+static struct link_dynamic_2 ld_2_copy;
+static struct ld_debug debug_copy;
+static CORE_ADDR debug_addr;
+static CORE_ADDR flag_addr;
+
+#else /* SVR4_SHARED_LIBS */
+
+#define LM_ADDR(so) ((so) -> lm.l_addr)
+#define LM_NEXT(so) ((so) -> lm.l_next)
+#define LM_NAME(so) ((so) -> lm.l_name)
+/* Test for first link map entry; first entry is the exec-file. */
+#define IGNORE_FIRST_LINK_MAP_ENTRY(x) ((x).l_prev == NULL)
+static struct r_debug debug_copy;
+char shadow_contents[BREAKPOINT_MAX]; /* Stash old bkpt addr contents */
+
+#endif /* !SVR4_SHARED_LIBS */
-/*
-** local data declarations
-*/
-#define MAX_PATH_SIZE 256
struct so_list {
- struct link_map inferior_lm; /* inferior link map */
- struct link_map *inferior_lm_add;
- long ld_text;
- char inferior_so_name[MAX_PATH_SIZE]; /* Shared Object Library Name */
- struct so_list *next; /* Next Structure */
- char symbols_loaded; /* Flag: loaded? */
- char from_tty; /* Flag: print msgs? */
- bfd *so_bfd;
- struct section_table *sections;
- struct section_table *sections_end;
+ struct so_list *next; /* next structure in linked list */
+ struct link_map lm; /* copy of link map from inferior */
+ struct link_map *lmaddr; /* addr in inferior lm was read from */
+ CORE_ADDR lmend; /* upper addr bound of mapped object */
+ char so_name[MAX_PATH_SIZE]; /* shared object lib name (FIXME) */
+ char symbols_loaded; /* flag: symbols read in yet? */
+ char from_tty; /* flag: print msgs? */
+ struct objfile *objfile; /* objfile for loaded lib */
+ struct section_table *sections;
+ struct section_table *sections_end;
+ struct section_table *textsection;
+ bfd *abfd;
};
-static struct so_list *so_list_head = 0;
+static struct so_list *so_list_head; /* List of known shared objects */
+static CORE_ADDR debug_base; /* Base of dynamic linker structures */
+static CORE_ADDR breakpoint_addr; /* Address where end bkpt is set */
+
+extern int
+fdmatch PARAMS ((int, int)); /* In libiberty */
+
+/* Local function prototypes */
+
+static void
+special_symbol_handling PARAMS ((struct so_list *));
+
+static void
+sharedlibrary_command PARAMS ((char *, int));
+
+static int
+enable_break PARAMS ((void));
+
+static int
+disable_break PARAMS ((void));
+
+static void
+info_sharedlibrary_command PARAMS ((char *, int));
+
+static int
+symbol_add_stub PARAMS ((char *));
+
+static struct so_list *
+find_solib PARAMS ((struct so_list *));
+
+static struct link_map *
+first_link_map_member PARAMS ((void));
+
+static CORE_ADDR
+locate_base PARAMS ((void));
+
+static void
+solib_map_sections PARAMS ((struct so_list *));
+
+#ifdef SVR4_SHARED_LIBS
+
+static CORE_ADDR
+elf_locate_base PARAMS ((void));
+
+#else
+
+static void
+allocate_rt_common_objfile PARAMS ((void));
+
+static void
+solib_add_common_symbols PARAMS ((struct rtc_symb *));
+
+#endif
/*
-** Build a section map for a shared library, record its text size in
-** the so_list structure and set up the text section of the shared lib.
-*/
+
+LOCAL FUNCTION
+
+ solib_map_sections -- open bfd and build sections for shared lib
+
+SYNOPSIS
+
+ static void solib_map_sections (struct so_list *so)
+
+DESCRIPTION
+
+ Given a pointer to one of the shared objects in our list
+ of mapped objects, use the recorded name to open a bfd
+ descriptor for the object, build a section table, and then
+ relocate all the section addresses by the base address at
+ which the shared object was mapped.
+
+FIXMES
+
+ In most (all?) cases the shared object file name recorded in the
+ dynamic linkage tables will be a fully qualified pathname. For
+ cases where it isn't, do we really mimic the systems search
+ mechanism correctly in the below code (particularly the tilde
+ expansion stuff?).
+ */
+
static void
-solib_map_sections(so)
-struct so_list *so;
+solib_map_sections (so)
+ struct so_list *so;
{
char *filename;
char *scratch_pathname;
int scratch_chan;
struct section_table *p;
+ struct cleanup *old_chain;
+ bfd *abfd;
- filename = tilde_expand (so->inferior_so_name);
- make_cleanup (free, filename);
+ 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)
- perror_with_name (filename);
-
- so->so_bfd = bfd_fdopenr (scratch_pathname, NULL, scratch_chan);
- if (!so->so_bfd)
- error ("Could not open `%s' as an executable file: %s",
- scratch_pathname, bfd_errmsg (bfd_error));
- if (!bfd_check_format (so->so_bfd, bfd_object))
- error ("\"%s\": not in executable format: %s.",
- scratch_pathname, bfd_errmsg (bfd_error));
- if (build_section_table (so->so_bfd, &so->sections, &so->sections_end))
- error ("Can't find the file sections in `%s': %s",
- exec_bfd->filename, bfd_errmsg (bfd_error));
-
- for (p = so->sections; p < so->sections_end; p++)
- {
- if (strcmp (bfd_section_name (so->so_bfd, p->sec_ptr), ".text") == 0)
+ {
+ perror_with_name (filename);
+ }
+ /* Leave scratch_pathname allocated. abfd->name will point to it. */
+
+ abfd = bfd_fdopenr (scratch_pathname, gnutarget, scratch_chan);
+ if (!abfd)
+ {
+ close (scratch_chan);
+ error ("Could not open `%s' as an executable file: %s",
+ scratch_pathname, bfd_errmsg (bfd_get_error ()));
+ }
+ /* Leave bfd open, core_xfer_memory and "info files" need it. */
+ 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.",
+ scratch_pathname, bfd_errmsg (bfd_get_error ()));
+ }
+ if (build_section_table (abfd, &so -> sections, &so -> sections_end))
+ {
+ error ("Can't find the file sections in `%s': %s",
+ bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
+ }
+
+ for (p = so -> sections; p < so -> sections_end; p++)
+ {
+ /* Relocate the section binding addresses as recorded in the shared
+ object's file by the base address to which the object was actually
+ mapped. */
+ 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 -> the_bfd_section -> name, ".text"))
{
- /* Determine length of text section and relocate it. */
- so->ld_text = p->endaddr - p->addr;
- p->addr += (CORE_ADDR)so->inferior_lm.lm_addr;
- p->endaddr += (CORE_ADDR)so->inferior_lm.lm_addr;
+ so -> textsection = p;
}
- else
- /* All other sections are ignored for now. */
- p->addr = p->endaddr = 0;
}
+
+ /* Free the file names, close the file now. */
+ do_cleanups (old_chain);
}
-/*=======================================================================*/
-
-/* find_solib
-**
-**Description:
-**
-** This module contains the routine which finds the names of any loaded
-** "images" in the current process. The argument in must be NULL on the
-** first call, and then the returned value must be passed in on
-** subsequent calls. This provides the capability to "step" down the
-** list of loaded objects. On the last object, a NULL value is returned.
-** The arg and return value are "struct link_map" pointers, as defined
-** in <link.h>.
-**
-** NOTE: This only works under SunOS4.0.
-*/
+#ifndef SVR4_SHARED_LIBS
+
+/* Allocate the runtime common object file. */
-struct so_list *find_solib(so_list_ptr)
-struct so_list *so_list_ptr; /* so_list_head position ptr */
+static void
+allocate_rt_common_objfile ()
{
-struct so_list *so_list_next = 0;
-struct link_map *inferior_lm = 0;
-struct link_dynamic inferior_dynamic_cpy;
-struct link_dynamic_2 inferior_ld_2_cpy;
-struct so_list *new;
-int i;
-
- if (!so_list_ptr) {
- if (!(so_list_next = so_list_head)) {
- i = lookup_misc_func ("_DYNAMIC");
- if (i >= 0) {
- read_memory(misc_function_vector[i].address,
- &inferior_dynamic_cpy,
- sizeof(struct link_dynamic));
- if (inferior_dynamic_cpy.ld_version == 3) {
- read_memory((CORE_ADDR)inferior_dynamic_cpy.ld_un.ld_2,
- &inferior_ld_2_cpy,
- sizeof(struct link_dynamic_2));
- inferior_lm = inferior_ld_2_cpy.ld_loaded;
- }
- }
- }
- } else {
- /*
- ** Advance to next local abbreviated load_map structure
- */
- if (!(inferior_lm = so_list_ptr->inferior_lm.lm_next)) {
- /* See if any were added, but be quiet if we can't read
- from the target any more. */
- int status;
-
- status = target_read_memory (
- (CORE_ADDR)so_list_ptr->inferior_lm_add,
- (char *)&so_list_ptr->inferior_lm,
- sizeof(struct link_map));
- if (status == 0)
- inferior_lm = so_list_ptr->inferior_lm.lm_next;
- else
- inferior_lm = 0;
- }
- so_list_next = so_list_ptr->next;
- }
- if ((!so_list_next) && inferior_lm) {
- /*
- ** Get Next LM Structure from inferior image and build
- ** an local abbreviated load_map structure
- */
- new = (struct so_list *) xmalloc(sizeof(struct so_list));
- new->inferior_lm_add = inferior_lm;
- read_memory((CORE_ADDR)inferior_lm,
- &new->inferior_lm,
- sizeof(struct link_map));
-
- read_memory((CORE_ADDR)new->inferior_lm.lm_name,
- new->inferior_so_name,
- MAX_PATH_SIZE - 1);
- new->inferior_so_name[MAX_PATH_SIZE - 1] = 0;
- /* Zero everything after the first terminating null */
- strncpy(new->inferior_so_name, new->inferior_so_name, MAX_PATH_SIZE);
-
-#if 0
- /* This doesn't work for core files, so instead get ld_text
- using solib_map_sections (below). */
- read_memory((CORE_ADDR)new->inferior_lm.lm_ld,
- &inferior_dynamic_cpy,
- sizeof(struct link_dynamic));
- read_memory((CORE_ADDR)inferior_dynamic_cpy.ld_un.ld_2,
- &inferior_ld_2_cpy,
- sizeof(struct link_dynamic_2));
- new->ld_text = inferior_ld_2_cpy.ld_text;
-#endif
+ struct objfile *objfile;
+ struct objfile *last_one;
- new->next = 0;
- new->symbols_loaded = 0;
- new->so_bfd = NULL;
- new->sections = NULL;
- if (so_list_ptr)
- so_list_ptr->next = new;
- else
- so_list_head = new;
+ objfile = (struct objfile *) xmalloc (sizeof (struct objfile));
+ memset (objfile, 0, sizeof (struct objfile));
+ objfile -> md = NULL;
+ 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");
- solib_map_sections (new);
+ /* 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;
+ }
- so_list_next = new;
- }
- return(so_list_next);
+ rt_common_objfile = objfile;
}
-/* A small stub to get us past the arg-passing pinhole of catch_errors. */
+/* Read all dynamically loaded common symbol definitions from the inferior
+ and put them into the minimal symbol table for the runtime common
+ objfile. */
-static int
-symbol_add_stub (arg)
- char *arg;
+static void
+solib_add_common_symbols (rtc_symp)
+ struct rtc_symb *rtc_symp;
{
- register struct so_list *so = (struct so_list *)arg; /* catch_errs bogon */
+ struct rtc_symb inferior_rtc_symb;
+ struct nlist inferior_rtc_nlist;
+ int len;
+ 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);
+
+ while (rtc_symp)
+ {
+ read_memory ((CORE_ADDR) rtc_symp,
+ (char *) &inferior_rtc_symb,
+ sizeof (inferior_rtc_symb));
+ read_memory ((CORE_ADDR) inferior_rtc_symb.rtc_sp,
+ (char *) &inferior_rtc_nlist,
+ sizeof(inferior_rtc_nlist));
+ if (inferior_rtc_nlist.n_type == N_COMM)
+ {
+ /* FIXME: The length of the symbol name is not available, but in the
+ current implementation the common symbol is allocated immediately
+ behind the name of the symbol. */
+ len = inferior_rtc_nlist.n_value - inferior_rtc_nlist.n_un.n_strx;
+
+ origname = name = xmalloc (len);
+ read_memory ((CORE_ADDR) inferior_rtc_nlist.n_un.n_name, name, len);
+
+ /* Allocate the runtime common objfile if necessary. */
+ if (rt_common_objfile == NULL)
+ allocate_rt_common_objfile ();
- symbol_file_add (so->inferior_so_name, so->from_tty,
- (unsigned int)so->inferior_lm.lm_addr, 0);
- return 1;
+ 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 the runtime common objfile. */
+
+ install_minimal_symbols (rt_common_objfile);
}
-/* The real work of adding a shared library file to the symtab and
- the section list. */
+#endif /* SVR4_SHARED_LIBS */
-void
-solib_add (arg_string, from_tty, target)
- char *arg_string;
- int from_tty;
- struct target_ops *target;
-{
- register struct so_list *so = 0; /* link map state variable */
- char *val;
- int count, old;
- struct section_table *sec;
- if (arg_string == 0)
- re_comp (".");
- else if (val = (char *) re_comp (arg_string)) {
- error ("Invalid regexp: %s", val);
- }
+#ifdef SVR4_SHARED_LIBS
- /* Getting new symbols may change our opinion about what is
- frameless. */
- reinit_frame_cache ();
-
- if (from_tty) {
- printf_filtered ("Shared libraries");
- if (arg_string)
- printf_filtered (" matching regular expresion \"%s\"", arg_string);
- printf_filtered (":\n");
- }
+#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
+
+ bfd_lookup_symbol -- lookup the value for a specific symbol
+
+SYNOPSIS
+
+ CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname)
+
+DESCRIPTION
+
+ An expensive way to lookup the value of a single symbol for
+ bfd's that are only temporary anyway. This is used by the
+ shared library support to find the address of the debugger
+ interface structures in the shared library.
+
+ Note that 0 is specifically allowed as an error return (no
+ such symbol).
+*/
+
+static CORE_ADDR
+bfd_lookup_symbol (abfd, symname)
+ bfd *abfd;
+ char *symname;
+{
+ unsigned int storage_needed;
+ asymbol *sym;
+ asymbol **symbol_table;
+ unsigned int number_of_symbols;
+ unsigned int i;
+ struct cleanup *back_to;
+ CORE_ADDR symaddr = 0;
- dont_repeat();
+ storage_needed = bfd_get_symtab_upper_bound (abfd);
- while (so = find_solib(so)) {
- if (re_exec(so->inferior_so_name)) {
- if (so->symbols_loaded) {
- if (from_tty)
- printf("Symbols already loaded for %s\n", so->inferior_so_name);
- } else {
- so->symbols_loaded = 1;
- so->from_tty = from_tty;
- catch_errors (symbol_add_stub, (char *)so,
- "Error while reading shared library symbols:\n");
- }
- }
- }
-
- /* Now add the shared library sections to the section table of the
- specified target, if any. */
- if (target) {
- /* Count how many new section_table entries there are. */
- so = 0;
- count = 0;
- while (0 != (so = find_solib (so))) {
- count += so->sections_end - so->sections;
- }
-
- if (count) {
- /* Reallocate the target's section table including the new size. */
- if (target->sections) {
- old = target->sections_end - target->sections;
- target->sections = (struct section_table *)
- realloc ((char *)target->sections,
- (sizeof (struct section_table)) * (count + old));
- } else {
- old = 0;
- target->sections = (struct section_table *)
- malloc ((sizeof (struct section_table)) * count);
- }
- target->sections_end = target->sections + (count + old);
-
- /* Add these section table entries to the target's table. */
- while (0 != (so = find_solib (so))) {
- count = so->sections_end - so->sections;
- bcopy (so->sections, (char *)(target->sections + old),
- (sizeof (struct section_table)) * count);
- old += count;
- }
- }
- }
+ if (storage_needed > 0)
+ {
+ symbol_table = (asymbol **) xmalloc (storage_needed);
+ back_to = make_cleanup (free, (PTR)symbol_table);
+ number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table);
+
+ for (i = 0; i < number_of_symbols; i++)
+ {
+ sym = *symbol_table++;
+ if (STREQ (sym -> name, symname))
+ {
+ /* Bfd symbols are section relative. */
+ symaddr = sym -> value + sym -> section -> vma;
+ break;
+ }
+ }
+ do_cleanups (back_to);
+ }
+ return (symaddr);
}
-/*=======================================================================*/
+/*
+
+LOCAL FUNCTION
+
+ look_for_base -- examine file for each mapped address segment
+
+SYNOPSYS
+
+ static int look_for_base (int fd, CORE_ADDR baseaddr)
+
+DESCRIPTION
+
+ This function is passed to proc_iterate_over_mappings, which
+ causes it to get called once for each mapped address space, with
+ an open file descriptor for the file mapped to that space, and the
+ base address of that mapped space.
-static void solib_info()
+ Our job is to find the debug base symbol in the file that this
+ fd is open on, if it exists, and if so, initialize the dynamic
+ linker structure base address debug_base.
+
+ Note that this is a computationally expensive proposition, since
+ we basically have to open a bfd on every call, so we specifically
+ avoid opening the exec file.
+ */
+
+static int
+look_for_base (fd, baseaddr)
+ int fd;
+ CORE_ADDR baseaddr;
{
-register struct so_list *so = 0; /* link map state variable */
+ bfd *interp_bfd;
+ 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
+ || (exec_bfd != NULL
+ && fdmatch (fileno ((GDB_FILE *)(exec_bfd -> iostream)), fd)))
+ {
+ return (0);
+ }
+
+ /* Try to open whatever random file this fd corresponds to. Note that
+ we have no way currently to find the filename. Don't gripe about
+ any problems we might have, just fail. */
- while (so = find_solib(so)) {
- if (so == so_list_head) {
- printf(" Address Range Syms Read Shared Object Library\n");
+ if ((interp_bfd = bfd_fdopenr ("unnamed", gnutarget, fd)) == NULL)
+ {
+ 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);
+ }
+
+ /* Now try to find our debug base symbol in this file, which we at
+ least know to be a valid ELF executable or shared library. */
+
+ for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++)
+ {
+ address = bfd_lookup_symbol (interp_bfd, *symbolp);
+ if (address != 0)
+ {
+ break;
}
- printf(" 0x%08x - 0x%08x %s %s\n",
- so->inferior_lm.lm_addr,
- so->inferior_lm.lm_addr + so->ld_text - 1,
- (so->symbols_loaded ? "Yes" : "No "),
- so->inferior_so_name);
}
- if (!so_list_head) {
- printf("No shared libraries loaded at this time.\n");
+ if (address == 0)
+ {
+ /* FIXME-leak: on failure, might not free all memory associated with
+ interp_bfd. */
+ bfd_close (interp_bfd);
+ return (0);
+ }
+
+ /* Eureka! We found the symbol. But now we may need to relocate it
+ by the base address. If the symbol's value is less than the base
+ address of the shared library, then it hasn't yet been relocated
+ by the dynamic linker, and we have to do it ourself. FIXME: Note
+ that we make the assumption that the first segment that corresponds
+ to the shared library has the base address to which the library
+ was relocated. */
+
+ if (address < baseaddr)
+ {
+ 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 */
/*
-** Called by Insert Breakpoint to see if Address is Shared Library Address
-*/
-int
-solib_address(address)
- CORE_ADDR address;
+
+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 ()
{
-register struct so_list *so = 0; /* link map state variable */
+ sec_ptr dyninfo_sect;
+ int dyninfo_sect_size;
+ CORE_ADDR dyninfo_addr;
+ char *buf;
+ char *bufend;
- while (so = find_solib(so)) {
- if ((address >= (CORE_ADDR) so->inferior_lm.lm_addr) &&
- (address < (CORE_ADDR) so->inferior_lm.lm_addr + so->ld_text))
- return 1;
- }
+ /* 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 */
+
/*
-** Called by free_all_symtabs
-*/
-void
-clear_solib()
-{
-struct so_list *next;
-
- while (so_list_head) {
- if (so_list_head->sections)
- free (so_list_head->sections);
- if (so_list_head->so_bfd)
- bfd_close (so_list_head->so_bfd);
- next = so_list_head->next;
- free(so_list_head);
- so_list_head = next;
- }
-}
-/* Called by child_create_inferior when the inferior is stopped at its
- first instruction. */
+LOCAL FUNCTION
-void
-solib_create_inferior_hook()
+ locate_base -- locate the base address of dynamic linker structs
+
+SYNOPSIS
+
+ CORE_ADDR locate_base (void)
+
+DESCRIPTION
+
+ For both the SunOS and SVR4 shared library implementations, if the
+ inferior executable has been linked dynamically, there is a single
+ address somewhere in the inferior's data space which is the key to
+ locating all of the dynamic linker's runtime structures. This
+ address is the value of the debug base symbol. The job of this
+ function is to find and return that address, or to return 0 if there
+ is no such address (the executable is statically linked for example).
+
+ For SunOS, the job is almost trivial, since the dynamic linker and
+ all of it's structures are statically linked to the executable at
+ link time. Thus the symbol for the address we are looking for has
+ already been added to the minimal symbol table for the executable's
+ objfile at the time the symbol file's symbols were read, and all we
+ 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 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.
+
+ */
+
+static CORE_ADDR
+locate_base ()
{
- struct link_dynamic inferior_dynamic_cpy;
- CORE_ADDR inferior_debug_addr;
- struct ld_debug inferior_debug_cpy;
- int in_debugger;
- CORE_ADDR in_debugger_addr;
- CORE_ADDR breakpoint_addr;
- int i, j;
-
- /* FIXME: We should look around in the executable code to find _DYNAMIC,
- if it isn't in the symbol table. It's not that hard to find...
- Then we can debug stripped executables using shared library symbols. */
- i = lookup_misc_func ("_DYNAMIC");
- if (i < 0) /* Can't find shared lib ptr. */
- return;
- if (misc_function_vector[i].address == 0) /* statically linked program */
- return;
- /* Get link_dynamic structure */
- j = target_read_memory(misc_function_vector[i].address,
- &inferior_dynamic_cpy,
- sizeof(struct link_dynamic));
- if (j) /* unreadable */
- return;
+#ifndef SVR4_SHARED_LIBS
- /* Calc address of debugger interface structure */
- inferior_debug_addr = (CORE_ADDR)inferior_dynamic_cpy.ldd;
- /* Calc address of `in_debugger' member of debugger interface structure */
- in_debugger_addr = inferior_debug_addr + (CORE_ADDR)((char *)&inferior_debug_cpy.ldd_in_debugger - (char *)&inferior_debug_cpy);
- /* Write a value of 1 to this member. */
- in_debugger = 1;
- write_memory(in_debugger_addr, &in_debugger, sizeof(in_debugger));
+ struct minimal_symbol *msymbol;
+ CORE_ADDR address = 0;
+ char **symbolp;
- /* Now run the target. Seeing `in_debugger' set, it will set a
- breakpoint at some convenient place, remember the original contents
- of that place, and eventually take a SIGTRAP when it runs into the
- breakpoint. We handle this by restoring the contents of the
- breakpointed location (which is only known after it stops),
- chasing around to locate the shared libraries that have been
- loaded, then resuming. */
+ /* For SunOS, we want to limit the search for the debug base symbol to the
+ executable being debugged, since there is a duplicate named symbol in the
+ shared library. We don't want the shared library versions. */
- clear_proceed_status ();
- stop_soon_quietly = 1;
- target_resume (0, 0);
- wait_for_inferior ();
- while (stop_signal != SIGTRAP)
+ for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++)
{
- /* FIXME, what if child has exit()ed? Must exit loop somehow */
- target_resume (0, stop_signal);
- wait_for_inferior ();
+ msymbol = lookup_minimal_symbol (*symbolp, NULL, symfile_objfile);
+ if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
+ {
+ address = SYMBOL_VALUE_ADDRESS (msymbol);
+ return (address);
+ }
}
- stop_soon_quietly = 0;
+ return (0);
- /* Set `in_debugger' to zero now. WHY, is this needed? */
- in_debugger = 0;
- write_memory(in_debugger_addr, &in_debugger, sizeof(in_debugger));
- read_memory(inferior_debug_addr, &inferior_debug_cpy, sizeof(inferior_debug_cpy));
- /* FIXME: maybe we should add the common symbols from the ldd_cp chain
- * to the misc_function_vector ?
- */
- breakpoint_addr = (CORE_ADDR)inferior_debug_cpy.ldd_bp_addr;
- if (stop_pc - DECR_PC_AFTER_BREAK == breakpoint_addr)
- {
- write_memory(breakpoint_addr, &inferior_debug_cpy.ldd_bp_inst, sizeof(inferior_debug_cpy.ldd_bp_inst));
- if (DECR_PC_AFTER_BREAK)
- {
- stop_pc -= DECR_PC_AFTER_BREAK;
- write_register (PC_REGNUM, stop_pc);
- }
- }
- solib_add ((char *)0, 0, (struct target_ops *)0);
-}
+#else /* SVR4_SHARED_LIBS */
+
+ /* 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, try to locate it in the dynamic info
+ section for ELF executables. */
+
+ if (debug_base == 0)
+ {
+ 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);
+
+#endif /* !SVR4_SHARED_LIBS */
-void
-sharedlibrary_command (args, from_tty)
-{
- solib_add (args, from_tty, (struct target_ops *)0);
}
-void
-_initialize_solib()
+/*
+
+LOCAL FUNCTION
+
+ first_link_map_member -- locate first member in dynamic linker's map
+
+SYNOPSIS
+
+ static struct link_map *first_link_map_member (void)
+
+DESCRIPTION
+
+ Read in a copy of the first member in the inferior's dynamic
+ link map from the inferior's dynamic linker structures, and return
+ a pointer to the copy in our address space.
+*/
+
+static struct link_map *
+first_link_map_member ()
{
+ struct link_map *lm = NULL;
- add_com("sharedlibrary", class_files, sharedlibrary_command,
- "Load shared object library symbols for files matching REGEXP.");
- add_info("sharedlibrary", solib_info,
- "Status of loaded shared object libraries");
+#ifndef SVR4_SHARED_LIBS
+
+ read_memory (debug_base, (char *) &dynamic_copy, sizeof (dynamic_copy));
+ if (dynamic_copy.ld_version >= 2)
+ {
+ /* It is a version that we can deal with, so read in the secondary
+ structure and find the address of the link map list from it. */
+ read_memory ((CORE_ADDR) dynamic_copy.ld_un.ld_2, (char *) &ld_2_copy,
+ sizeof (struct link_dynamic_2));
+ lm = ld_2_copy.ld_loaded;
+ }
+
+#else /* SVR4_SHARED_LIBS */
+
+ read_memory (debug_base, (char *) &debug_copy, sizeof (struct r_debug));
+ /* FIXME: Perhaps we should validate the info somehow, perhaps by
+ checking r_version for a known version number, or r_state for
+ RT_CONSISTENT. */
+ lm = debug_copy.r_map;
+
+#endif /* !SVR4_SHARED_LIBS */
+
+ return (lm);
+}
+
+/*
+
+LOCAL FUNCTION
+
+ find_solib -- step through list of shared objects
+
+SYNOPSIS
+
+ struct so_list *find_solib (struct so_list *so_list_ptr)
+
+DESCRIPTION
+
+ This module contains the routine which finds the names of any
+ loaded "images" in the current process. The argument in must be
+ NULL on the first call, and then the returned value must be passed
+ in on subsequent calls. This provides the capability to "step" down
+ the list of loaded objects. On the last object, a NULL value is
+ returned.
+
+ The arg and return value are "struct link_map" pointers, as defined
+ in <link.h>.
+ */
+
+static struct so_list *
+find_solib (so_list_ptr)
+ struct so_list *so_list_ptr; /* Last lm or NULL for first one */
+{
+ struct so_list *so_list_next = NULL;
+ struct link_map *lm = NULL;
+ struct so_list *new;
+
+ if (so_list_ptr == NULL)
+ {
+ /* We are setting up for a new scan through the loaded images. */
+ if ((so_list_next = so_list_head) == NULL)
+ {
+ /* We have not already read in the dynamic linking structures
+ from the inferior, lookup the address of the base structure. */
+ debug_base = locate_base ();
+ if (debug_base != 0)
+ {
+ /* Read the base structure in and find the address of the first
+ link map list member. */
+ lm = first_link_map_member ();
+ }
+ }
+ }
+ else
+ {
+ /* We have been called before, and are in the process of walking
+ the shared library list. Advance to the next shared object. */
+ if ((lm = LM_NEXT (so_list_ptr)) == NULL)
+ {
+ /* We have hit the end of the list, so check to see if any were
+ added, but be quiet if we can't read from the target any more. */
+ int status = target_read_memory ((CORE_ADDR) so_list_ptr -> lmaddr,
+ (char *) &(so_list_ptr -> lm),
+ sizeof (struct link_map));
+ if (status == 0)
+ {
+ lm = LM_NEXT (so_list_ptr);
+ }
+ else
+ {
+ lm = NULL;
+ }
+ }
+ so_list_next = so_list_ptr -> next;
+ }
+ if ((so_list_next == NULL) && (lm != NULL))
+ {
+ /* Get next link map structure from inferior image and build a local
+ abbreviated load_map structure */
+ new = (struct so_list *) xmalloc (sizeof (struct so_list));
+ memset ((char *) new, 0, sizeof (struct so_list));
+ new -> lmaddr = lm;
+ /* Add the new node as the next node in the list, or as the root
+ node if this is the first one. */
+ if (so_list_ptr != NULL)
+ {
+ so_list_ptr -> next = new;
+ }
+ else
+ {
+ so_list_head = new;
+ }
+ so_list_next = new;
+ read_memory ((CORE_ADDR) lm, (char *) &(new -> lm),
+ sizeof (struct link_map));
+ /* For SVR4 versions, the first entry in the link map is for the
+ inferior executable, so we must ignore it. For some versions of
+ SVR4, it has no name. For others (Solaris 2.3 for example), it
+ does have a name, so we can no longer use a missing name to
+ decide when to ignore it. */
+ if (!IGNORE_FIRST_LINK_MAP_ENTRY (new -> lm))
+ {
+ int errcode;
+ char *buffer;
+ target_read_string ((CORE_ADDR) LM_NAME (new), &buffer,
+ MAX_PATH_SIZE - 1, &errcode);
+ if (errcode != 0)
+ error ("find_solib: Can't read pathname for load map: %s\n",
+ safe_strerror (errcode));
+ strncpy (new -> so_name, buffer, MAX_PATH_SIZE - 1);
+ new -> so_name[MAX_PATH_SIZE - 1] = '\0';
+ free (buffer);
+ solib_map_sections (new);
+ }
+ }
+ return (so_list_next);
+}
+
+/* A small stub to get us past the arg-passing pinhole of catch_errors. */
+
+static int
+symbol_add_stub (arg)
+ char *arg;
+{
+ register struct so_list *so = (struct so_list *) arg; /* catch_errs bogon */
+
+ 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
+
+ solib_add -- add a shared library file to the symtab and section list
+
+SYNOPSIS
+
+ void solib_add (char *arg_string, int from_tty,
+ struct target_ops *target)
+
+DESCRIPTION
+
+*/
+
+void
+solib_add (arg_string, from_tty, target)
+ char *arg_string;
+ int from_tty;
+ struct target_ops *target;
+{
+ register struct so_list *so = NULL; /* link map state variable */
+
+ /* Last shared library that we read. */
+ struct so_list *so_last = NULL;
+
+ char *re_err;
+ int count;
+ int old;
+
+ if ((re_err = re_comp (arg_string ? arg_string : ".")) != NULL)
+ {
+ error ("Invalid regexp: %s", re_err);
+ }
+
+ /* Add the shared library sections to the section table of the
+ specified target, if any. */
+ if (target)
+ {
+ /* Count how many new section_table entries there are. */
+ so = NULL;
+ count = 0;
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so -> so_name[0] && !match_main (so -> so_name))
+ {
+ count += so -> sections_end - so -> sections;
+ }
+ }
+
+ if (count)
+ {
+ /* Reallocate the target's section table including the new size. */
+ if (target -> to_sections)
+ {
+ old = target -> to_sections_end - target -> to_sections;
+ target -> to_sections = (struct section_table *)
+ xrealloc ((char *)target -> to_sections,
+ (sizeof (struct section_table)) * (count + old));
+ }
+ else
+ {
+ old = 0;
+ target -> to_sections = (struct section_table *)
+ xmalloc ((sizeof (struct section_table)) * count);
+ }
+ target -> to_sections_end = target -> to_sections + (count + old);
+
+ /* Add these section table entries to the target's table. */
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so -> so_name[0])
+ {
+ count = so -> sections_end - so -> sections;
+ memcpy ((char *) (target -> to_sections + old),
+ so -> sections,
+ (sizeof (struct section_table)) * count);
+ old += count;
+ }
+ }
+ }
+ }
+
+ /* 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;
+ }
+ }
+ }
+
+ /* 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);
+}
+
+/*
+
+LOCAL FUNCTION
+
+ info_sharedlibrary_command -- code for "info sharedlibrary"
+
+SYNOPSIS
+
+ static void info_sharedlibrary_command ()
+
+DESCRIPTION
+
+ Walk through the shared library list and print information
+ about each attached library.
+*/
+
+static void
+info_sharedlibrary_command (ignore, from_tty)
+ char *ignore;
+ int from_tty;
+{
+ register struct so_list *so = NULL; /* link map state variable */
+ int header_done = 0;
+
+ if (exec_bfd == NULL)
+ {
+ printf_unfiltered ("No exec file.\n");
+ return;
+ }
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so -> so_name[0])
+ {
+ if (!header_done)
+ {
+ printf_unfiltered("%-12s%-12s%-12s%s\n", "From", "To", "Syms Read",
+ "Shared Object Library");
+ header_done++;
+ }
+ /* FIXME-32x64: need print_address_numeric with field width or
+ some such. */
+ printf_unfiltered ("%-12s",
+ local_hex_string_custom ((unsigned long) LM_ADDR (so),
+ "08l"));
+ printf_unfiltered ("%-12s",
+ local_hex_string_custom ((unsigned long) so -> lmend,
+ "08l"));
+ printf_unfiltered ("%-12s", so -> symbols_loaded ? "Yes" : "No");
+ printf_unfiltered ("%s\n", so -> so_name);
+ }
+ }
+ if (so_list_head == NULL)
+ {
+ printf_unfiltered ("No shared libraries loaded at this time.\n");
+ }
+}
+
+/*
+
+GLOBAL FUNCTION
+
+ solib_address -- check to see if an address is in a shared lib
+
+SYNOPSIS
+
+ int solib_address (CORE_ADDR address)
+
+DESCRIPTION
+
+ Provides a hook for other gdb routines to discover whether or
+ not a particular address is within the mapped address space of
+ a shared library. Any address between the base mapping address
+ and the first address beyond the end of the last mapping, is
+ considered to be within the shared library address space, for
+ our purposes.
+
+ For example, this routine is called at one point to disable
+ breakpoints which are in shared libraries that are not currently
+ mapped in.
+ */
+
+int
+solib_address (address)
+ CORE_ADDR address;
+{
+ register struct so_list *so = 0; /* link map state variable */
+
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so -> so_name[0])
+ {
+ if ((address >= (CORE_ADDR) LM_ADDR (so)) &&
+ (address < (CORE_ADDR) so -> lmend))
+ {
+ return (1);
+ }
+ }
+ }
+ return (0);
+}
+
+/* Called by free_all_symtabs */
+
+void
+clear_solib()
+{
+ struct so_list *next;
+ char *bfd_filename;
+
+ while (so_list_head)
+ {
+ if (so_list_head -> sections)
+ {
+ free ((PTR)so_list_head -> sections);
+ }
+ if (so_list_head -> abfd)
+ {
+ bfd_filename = bfd_get_filename (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. */
+ bfd_filename = NULL;
+
+ next = so_list_head -> next;
+ if (bfd_filename)
+ free ((PTR)bfd_filename);
+ free ((PTR)so_list_head);
+ so_list_head = next;
+ }
+ debug_base = 0;
+}
+
+/*
+
+LOCAL FUNCTION
+
+ disable_break -- remove the "mapping changed" breakpoint
+
+SYNOPSIS
+
+ static int disable_break ()
+
+DESCRIPTION
+
+ Removes the breakpoint that gets hit when the dynamic linker
+ completes a mapping change.
+
+*/
+
+static int
+disable_break ()
+{
+ int status = 1;
+
+#ifndef SVR4_SHARED_LIBS
+
+ int in_debugger = 0;
+
+ /* Read the debugger structure from the inferior to retrieve the
+ address of the breakpoint and the original contents of the
+ breakpoint address. Remove the breakpoint by writing the original
+ contents back. */
+
+ read_memory (debug_addr, (char *) &debug_copy, sizeof (debug_copy));
+
+ /* Set `in_debugger' to zero now. */
+
+ write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger));
+
+ breakpoint_addr = (CORE_ADDR) debug_copy.ldd_bp_addr;
+ write_memory (breakpoint_addr, (char *) &debug_copy.ldd_bp_inst,
+ sizeof (debug_copy.ldd_bp_inst));
+
+#else /* SVR4_SHARED_LIBS */
+
+ /* Note that breakpoint address and original contents are in our address
+ space, so we just need to write the original contents back. */
+
+ if (memory_remove_breakpoint (breakpoint_addr, shadow_contents) != 0)
+ {
+ status = 0;
+ }
+
+#endif /* !SVR4_SHARED_LIBS */
+
+ /* For the SVR4 version, we always know the breakpoint address. For the
+ SunOS version we don't know it until the above code is executed.
+ Grumble if we are stopped anywhere besides the breakpoint address. */
+
+ if (stop_pc != breakpoint_addr)
+ {
+ warning ("stopped at unknown breakpoint while handling shared libraries");
+ }
+
+ return (status);
+}
+
+/*
+
+LOCAL FUNCTION
+
+ enable_break -- arrange for dynamic linker to hit breakpoint
+
+SYNOPSIS
+
+ int enable_break (void)
+
+DESCRIPTION
+
+ Both the SunOS and the SVR4 dynamic linkers have, as part of their
+ debugger interface, support for arranging for the inferior to hit
+ a breakpoint after mapping in the shared libraries. This function
+ enables that breakpoint.
+
+ For SunOS, there is a special flag location (in_debugger) which we
+ set to 1. When the dynamic linker sees this flag set, it will set
+ a breakpoint at a location known only to itself, after saving the
+ original contents of that place and the breakpoint address itself,
+ in it's own internal structures. When we resume the inferior, it
+ will eventually take a SIGTRAP when it runs into the breakpoint.
+ We handle this (in a different place) by restoring the contents of
+ the breakpointed location (which is only known after it stops),
+ chasing around to locate the shared libraries that have been
+ loaded, then resuming.
+
+ For SVR4, the debugger interface structure contains a member (r_brk)
+ which is statically initialized at the time the shared library is
+ built, to the offset of a function (_r_debug_state) which is guaran-
+ teed to be called once before mapping in a library, and again when
+ the mapping is complete. At the time we are examining this member,
+ it contains only the unrelocated offset of the function, so we have
+ to do our own relocation. Later, when the dynamic linker actually
+ runs, it relocates r_brk to be the actual address of _r_debug_state().
+
+ The debugger interface structure also contains an enumeration which
+ is set to either RT_ADD or RT_DELETE prior to changing the mapping,
+ depending upon whether or not the library is being mapped or unmapped,
+ and then set to RT_CONSISTENT after the library is mapped/unmapped.
+*/
+
+static int
+enable_break ()
+{
+ int success = 0;
+
+#ifndef SVR4_SHARED_LIBS
+
+ int j;
+ int in_debugger;
+
+ /* Get link_dynamic structure */
+
+ j = target_read_memory (debug_base, (char *) &dynamic_copy,
+ sizeof (dynamic_copy));
+ if (j)
+ {
+ /* unreadable */
+ return (0);
+ }
+
+ /* Calc address of debugger interface structure */
+
+ debug_addr = (CORE_ADDR) dynamic_copy.ldd;
+
+ /* Calc address of `in_debugger' member of debugger interface structure */
+
+ flag_addr = debug_addr + (CORE_ADDR) ((char *) &debug_copy.ldd_in_debugger -
+ (char *) &debug_copy);
+
+ /* Write a value of 1 to this member. */
+
+ in_debugger = 1;
+ write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger));
+ success = 1;
+
+#else /* SVR4_SHARED_LIBS */
+
+#ifdef BKPT_AT_SYMBOL
+
+ struct minimal_symbol *msymbol;
+ char **bkpt_namep;
+ CORE_ADDR bkpt_addr;
+
+ /* 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, 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;
+ }
+ }
+ }
+
+#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;
+
+#endif /* BKPT_AT_SYMBOL */
+
+#endif /* !SVR4_SHARED_LIBS */
+
+ return (success);
+}
+
+/*
+
+GLOBAL FUNCTION
+
+ solib_create_inferior_hook -- shared library startup support
+
+SYNOPSIS
+
+ void solib_create_inferior_hook()
+
+DESCRIPTION
+
+ When gdb starts up the inferior, it nurses it along (through the
+ shell) until it is ready to execute it's first instruction. At this
+ point, this function gets called via expansion of the macro
+ SOLIB_CREATE_INFERIOR_HOOK.
+
+ For SunOS executables, this first instruction is typically the
+ one at "_start", or a similar text label, regardless of whether
+ the executable is statically or dynamically linked. The runtime
+ startup code takes care of dynamically linking in any shared
+ libraries, once gdb allows the inferior to continue.
+
+ For SVR4 executables, this first instruction is either the first
+ instruction in the dynamic linker (for dynamically linked
+ executables) or the instruction at "start" for statically linked
+ executables. For dynamically linked executables, the system
+ first exec's /lib/libc.so.N, which contains the dynamic linker,
+ and starts it running. The dynamic linker maps in any needed
+ shared libraries, maps in the actual user executable, and then
+ jumps to "start" in the user executable.
+
+ For both SunOS shared libraries, and SVR4 shared libraries, we
+ can arrange to cooperate with the dynamic linker to discover the
+ names of shared libraries that are dynamically linked, and the
+ base addresses to which they are linked.
+
+ This function is responsible for discovering those names and
+ addresses, and saving sufficient information about them to allow
+ their symbols to be read at a later time.
+
+FIXME
+
+ Between enable_break() and disable_break(), this code does not
+ properly handle hitting breakpoints which the user might have
+ set in the startup code or in the dynamic linker itself. Proper
+ handling will probably have to wait until the implementation is
+ changed to use the "breakpoint handler function" method.
+
+ Also, what if child has exit()ed? Must exit loop somehow.
+ */
+
+void
+solib_create_inferior_hook()
+{
+ /* If we are using the BKPT_AT_SYMBOL code, then we don't need the base
+ yet. In fact, in the case of a SunOS4 executable being run on
+ Solaris, we can't get it yet. find_solib will get it when it needs
+ it. */
+#if !(defined (SVR4_SHARED_LIBS) && defined (BKPT_AT_SYMBOL))
+ if ((debug_base = locate_base ()) == 0)
+ {
+ /* Can't find the symbol or the executable is statically linked. */
+ return;
+ }
+#endif
+
+ if (!enable_break ())
+ {
+ warning ("shared library handler failed to enable breakpoint");
+ return;
+ }
+
+ /* 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. */
+
+ clear_proceed_status ();
+ stop_soon_quietly = 1;
+ stop_signal = TARGET_SIGNAL_0;
+ do
+ {
+ target_resume (-1, 0, stop_signal);
+ wait_for_inferior ();
+ }
+ while (stop_signal != TARGET_SIGNAL_TRAP);
+ stop_soon_quietly = 0;
+
+ /* We are now either at the "mapping complete" breakpoint (or somewhere
+ else, a condition we aren't prepared to deal with anyway), so adjust
+ the PC as necessary after a breakpoint, disable the breakpoint, and
+ add any shared libraries that were mapped in. */
+
+ if (DECR_PC_AFTER_BREAK)
+ {
+ stop_pc -= DECR_PC_AFTER_BREAK;
+ write_register (PC_REGNUM, stop_pc);
+ }
+
+ if (!disable_break ())
+ {
+ warning ("shared library handler failed to disable breakpoint");
+ }
+
+ if (auto_solib_add_at_startup)
+ solib_add ((char *) 0, 0, (struct target_ops *) 0);
+}
+
+/*
+
+LOCAL FUNCTION
+
+ special_symbol_handling -- additional shared library symbol handling
+
+SYNOPSIS
+
+ void special_symbol_handling (struct so_list *so)
+
+DESCRIPTION
+
+ Once the symbols from a shared object have been loaded in the usual
+ way, we are called to do any system specific symbol handling that
+ is needed.
+
+ 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.
+
+*/
+
+static void
+special_symbol_handling (so)
+struct so_list *so;
+{
+#ifndef SVR4_SHARED_LIBS
+ int j;
+
+ if (debug_addr == 0)
+ {
+ /* Get link_dynamic structure */
+
+ j = target_read_memory (debug_base, (char *) &dynamic_copy,
+ sizeof (dynamic_copy));
+ if (j)
+ {
+ /* unreadable */
+ return;
+ }
+
+ /* Calc address of debugger interface structure */
+ /* FIXME, this needs work for cross-debugging of core files
+ (byteorder, size, alignment, etc). */
+
+ debug_addr = (CORE_ADDR) dynamic_copy.ldd;
+ }
+
+ /* Read the debugger structure from the inferior, just to make sure
+ we have a current copy. */
+
+ j = target_read_memory (debug_addr, (char *) &debug_copy,
+ sizeof (debug_copy));
+ if (j)
+ return; /* unreadable */
+
+ /* Get common symbol definitions for the loaded object. */
+
+ if (debug_copy.ldd_cp)
+ {
+ solib_add_common_symbols (debug_copy.ldd_cp);
+ }
+
+#endif /* !SVR4_SHARED_LIBS */
+}
+
+
+/*
+
+LOCAL FUNCTION
+
+ sharedlibrary_command -- handle command to explicitly add library
+
+SYNOPSIS
+
+ static void sharedlibrary_command (char *args, int from_tty)
+
+DESCRIPTION
+
+*/
+
+static void
+sharedlibrary_command (args, from_tty)
+char *args;
+int from_tty;
+{
+ dont_repeat ();
+ solib_add (args, from_tty, (struct target_ops *) 0);
+}
+
+void
+_initialize_solib()
+{
+
+ add_com ("sharedlibrary", class_files, sharedlibrary_command,
+ "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_at_startup,
+ "Set autoloading of shared library symbols at startup.\n\
+If nonzero, symbols from all shared object libraries will be loaded\n\
+automatically when the inferior begins execution. Otherwise, symbols\n\
+must be loaded manually, using `sharedlibrary'.",
+ &setlist),
+ &showlist);
}
projects / deliverable / binutils-gdb.git / blobdiff