-/* Copyright (C) 1990 Free Software Foundation, Inc.
+/* Handle SunOS and SVR4 shared libraries for GDB, the GNU Debugger.
+ Copyright 1990, 91, 92, 93, 94, 95, 96, 98, 1999
+ Free Software Foundation, Inc.
-This file is part of GDB.
+ This file is part of GDB.
-GDB is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 1, or (at your option)
-any later version.
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
-GDB is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
-You should have received a copy of the GNU General Public License
-along with GDB; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ 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., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+
+#include "defs.h"
+
+/* This file is only compilable if link.h is available. */
+
+#ifdef HAVE_LINK_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"
+
+#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 "gnu-regex.h"
+#include "inferior.h"
+#include "environ.h"
+#include "language.h"
+#include "gdbcmd.h"
-/*
-** 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 */
- int symbols_loaded;
- bfd *so_bfd;
- struct section_table *so_sections;
- struct section_table *so_sections_end;
+#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.
+
+ 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. */
+
+#ifdef SVR4_SHARED_LIBS
+static char *solib_break_names[] =
+{
+ "r_debug_state",
+ "_r_debug_state",
+ "_dl_debug_state",
+ "rtld_db_dlactivity",
+ NULL
};
+#endif
-static struct so_list *so_list_head = 0;
+#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 */
+
+#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 */
+
+struct so_list
+ {
+ 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; /* 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 */
+
+static int solib_cleanup_queued = 0; /* make_run_cleanup called */
+
+extern int
+fdmatch PARAMS ((int, int)); /* In libiberty */
+
+/* Local function prototypes */
+
+static void
+do_clear_solib PARAMS ((PTR));
+
+static int
+match_main PARAMS ((char *));
+
+static void
+special_symbol_handling PARAMS ((struct so_list *));
+
+static void
+sharedlibrary_command PARAMS ((char *, int));
+
+static int
+enable_break PARAMS ((void));
+
+static void
+info_sharedlibrary_command PARAMS ((char *, int));
+
+static int symbol_add_stub PARAMS ((PTR));
+
+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 int solib_map_sections PARAMS ((PTR));
+
+#ifdef SVR4_SHARED_LIBS
+
+static CORE_ADDR
+ elf_locate_base PARAMS ((void));
+
+#else
+
+static int
+disable_break PARAMS ((void));
+
+static void
+allocate_rt_common_objfile PARAMS ((void));
-/*
-** 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.
-*/
static void
-solib_map_sections(so)
-struct so_list *so;
+solib_add_common_symbols PARAMS ((struct rtc_symb *));
+
+#endif
+
+void _initialize_solib PARAMS ((void));
+
+/* If non-zero, this is a prefix that will be added to the front of the name
+ shared libraries with an absolute filename for loading. */
+static char *solib_absolute_prefix = NULL;
+
+/* If non-empty, this is a search path for loading non-absolute shared library
+ symbol files. This takes precedence over the environment variables PATH
+ and LD_LIBRARY_PATH. */
+static char *solib_search_path = NULL;
+
+/*
+
+ LOCAL FUNCTION
+
+ solib_map_sections -- open bfd and build sections for shared lib
+
+ SYNOPSIS
+
+ static int 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 int
+solib_map_sections (arg)
+ PTR arg;
{
+ struct so_list *so = (struct so_list *) arg; /* catch_errors bogon */
char *filename;
char *scratch_pathname;
int scratch_chan;
struct section_table *p;
-
- filename = tilde_expand (so->inferior_so_name);
- make_cleanup (free, filename);
-
- scratch_chan = openp (getenv ("PATH"), 1, filename, O_RDONLY, 0,
- &scratch_pathname);
+ struct cleanup *old_chain;
+ bfd *abfd;
+
+ filename = tilde_expand (so->so_name);
+
+ if (solib_absolute_prefix && ROOTED_P (filename))
+ /* Prefix shared libraries with absolute filenames with
+ SOLIB_ABSOLUTE_PREFIX. */
+ {
+ char *pfxed_fn;
+ int pfx_len;
+
+ pfx_len = strlen (solib_absolute_prefix);
+
+ /* Remove trailing slashes. */
+ while (pfx_len > 0 && SLASH_P (solib_absolute_prefix[pfx_len - 1]))
+ pfx_len--;
+
+ pfxed_fn = xmalloc (pfx_len + strlen (filename) + 1);
+ strcpy (pfxed_fn, solib_absolute_prefix);
+ strcat (pfxed_fn, filename);
+ free (filename);
+
+ filename = pfxed_fn;
+ }
+
+ old_chain = make_cleanup (free, filename);
+
+ scratch_chan = -1;
+
+ if (solib_search_path)
+ scratch_chan = openp (solib_search_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, "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->so_sections, &so->so_sections_end))
- error ("Can't find the file sections in `%s': %s",
- exec_bfd->filename, bfd_errmsg (bfd_error));
-
- for (p = so->so_sections; p < so->so_sections_end; p++)
- {
- if (strcmp (bfd_section_name (so->so_bfd, p->sec_ptr), ".text") == 0)
+ {
+ 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);
+ }
+ /* 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);
+
+ return (1);
}
-/*=======================================================================*/
-
-/* 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.
-*/
-
-struct so_list *find_solib(so_list_ptr)
-struct so_list *so_list_ptr; /* so_list_head position ptr */
+#ifndef SVR4_SHARED_LIBS
+
+/* Allocate the runtime common object file. */
+
+static void
+allocate_rt_common_objfile ()
{
-struct so_list *so_list_next = 0;
-CORE_ADDR inferior_dynamic_ptr = 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)) {
- for (i = 0; i < misc_function_count; i++) {
- if (!strcmp (misc_function_vector[i].name, "_DYNAMIC")) {
- inferior_dynamic_ptr = misc_function_vector[i].address;
- break;
- }
- }
- if (inferior_dynamic_ptr) {
- read_memory(inferior_dynamic_ptr, &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,
- &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;
+
+ 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");
- new->next = 0;
- new->symbols_loaded = 0;
- new->so_bfd = NULL;
- new->so_sections = NULL;
- if (so_list_ptr)
- so_list_ptr->next = new;
- else
- so_list_head = new;
+ /* Add this file onto the tail of the linked list of other such files. */
- solib_map_sections (new);
+ 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;
}
-/*
-** Called by core_xfer_memory if the transfer form the core file failed.
-** We try to satisfy the request from the text sections of the shared libs.
-*/
-int
-solib_xfer_memory (memaddr, myaddr, len, write)
- CORE_ADDR memaddr;
- char *myaddr;
- int len;
- int write;
+/* 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)
+ struct rtc_symb *rtc_symp;
{
- int res;
- register struct so_list *so = 0;
+ struct rtc_symb inferior_rtc_symb;
+ struct nlist inferior_rtc_nlist;
+ int len;
+ char *name;
- while (so = find_solib(so))
+ /* Remove any runtime common symbols from previous runs. */
+
+ if (rt_common_objfile != NULL && rt_common_objfile->minimal_symbol_count)
{
- res = xfer_memory (memaddr, myaddr, len, write,
- so->so_bfd, so->so_sections, so->so_sections_end);
- if (res)
- return res;
+ 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;
}
- return 0;
-}
-/*=======================================================================*/
-void solib_add(arg_string, from_tty)
-char *arg_string;
-int from_tty;
-{
- register struct so_list *so = 0; /* link map state variable */
- char *val;
+ init_minimal_symbol_collection ();
+ make_cleanup ((make_cleanup_func) 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;
+
+ 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 ();
- if (arg_string == 0)
- re_comp (".");
- else if (val = (char *) re_comp (arg_string)) {
- error ("Invalid regexp: %s", val);
+ prim_record_minimal_symbol (name, inferior_rtc_nlist.n_value,
+ mst_bss, rt_common_objfile);
+ free (name);
+ }
+ rtc_symp = inferior_rtc_symb.rtc_next;
}
- /* Getting new symbols may change our opinion about what is
- frameless. */
- reinit_frame_cache ();
-
- printf_filtered ("All shared libraries");
- if (arg_string)
- printf_filtered (" matching regular expresion \"%s\"", arg_string);
- printf_filtered (":\n");
-
- dont_repeat();
-
- while (so = find_solib(so)) {
- if (re_exec(so->inferior_so_name)) {
- if (so->symbols_loaded) {
- printf("Symbols already loaded for %s\n", so->inferior_so_name);
- } else {
- symbol_file_add (so->inferior_so_name, from_tty,
- (unsigned int)so->inferior_lm.lm_addr, 0);
- so->symbols_loaded = 1;
+ /* Install any minimal symbols that have been collected as the current
+ minimal symbols for the runtime common objfile. */
+
+ install_minimal_symbols (rt_common_objfile);
+}
+
+#endif /* SVR4_SHARED_LIBS */
+
+
+#ifdef SVR4_SHARED_LIBS
+
+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;
+
+ storage_needed = bfd_get_symtab_upper_bound (abfd);
+
+ 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);
}
-/*=======================================================================*/
-static void solib_info()
+#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));
+
+/*
+
+ 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.
+
+ 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 ((FILE *) (exec_bfd->iostream)), fd)))
+ {
+ return (0);
+ }
- while (so = find_solib(so)) {
- if (so == so_list_head) {
- printf(" Address Range Symbols Shared Object Library\n");
+ /* 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. */
+
+ 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. */
+#ifndef TARGET_ELF64
+ 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
+ }
+#else /* ELF64 */
+ for (bufend = buf + dyninfo_sect_size;
+ buf < bufend;
+ buf += sizeof (Elf64_External_Dyn))
+ {
+ Elf64_External_Dyn *x_dynp = (Elf64_External_Dyn *) buf;
+ long dyn_tag;
+ CORE_ADDR dyn_ptr;
+
+ dyn_tag = bfd_h_get_64 (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_64 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr);
+ return dyn_ptr;
+ }
+ }
+#endif
+
+ /* DT_DEBUG entry not found. */
+ return 0;
}
+#endif /* SVR4_SHARED_LIBS */
+
/*
-** Called by free_all_symtabs
-*/
-void
-clear_solib()
+
+ LOCAL FUNCTION
+
+ 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 so_list *next;
-
- while (so_list_head) {
- if (so_list_head->so_sections)
- free (so_list_head->so_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;
- }
-
+
+#ifndef SVR4_SHARED_LIBS
+
+ struct minimal_symbol *msymbol;
+ CORE_ADDR address = 0;
+ char **symbolp;
+
+ /* 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. */
+
+ for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++)
+ {
+ msymbol = lookup_minimal_symbol (*symbolp, NULL, symfile_objfile);
+ if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
+ {
+ address = SYMBOL_VALUE_ADDRESS (msymbol);
+ return (address);
+ }
+ }
+ return (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 && target_has_execution)
+ proc_iterate_over_mappings (look_for_base);
+#endif
+ }
+ return (debug_base);
+
+#endif /* !SVR4_SHARED_LIBS */
+
}
-void
-_initialize_solib()
-{
+/*
- add_com("sharedlibrary", class_files, solib_add,
- "Load shared object library symbols for files matching REGEXP.");
- add_info("sharedlibrary", solib_info,
- "Status of loaded shared object libraries");
+ 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;
+
+#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);
+}
+
+#ifdef SVR4_SHARED_LIBS
+/*
+
+ LOCAL FUNCTION
+
+ open_exec_file_object
+
+ SYNOPSIS
+
+ void open_symbol_file_object (int from_tty)
+
+ DESCRIPTION
+
+ If no open symbol file, attempt to locate and open the main symbol
+ file. On SVR4 systems, this is the first link map entry. If its
+ name is here, we can open it. Useful when attaching to a process
+ without first loading its symbol file.
+
+ */
+
+int
+open_symbol_file_object (arg)
+ PTR arg;
+{
+ int from_tty = (int) arg; /* sneak past catch_errors */
+ struct link_map *lm, lmcopy;
+ char *filename;
+ int errcode;
+
+ if (symfile_objfile)
+ if (!query ("Attempt to reload symbols from process? "))
+ return 0;
+
+ if ((debug_base = locate_base ()) == 0)
+ return 0; /* failed somehow... */
+
+ /* First link map member should be the executable. */
+ if ((lm = first_link_map_member ()) == NULL)
+ return 0; /* failed somehow... */
+
+ /* Read from target memory to GDB. */
+ read_memory ((CORE_ADDR) lm, (void *) &lmcopy, sizeof (lmcopy));
+
+ if (lmcopy.l_name == 0)
+ return 0; /* no filename. */
+
+ /* Now fetch the filename from target memory. */
+ target_read_string ((CORE_ADDR) lmcopy.l_name, &filename,
+ MAX_PATH_SIZE - 1, &errcode);
+ if (errcode)
+ {
+ warning ("failed to read exec filename from attached file: %s",
+ safe_strerror (errcode));
+ return 0;
+ }
+
+ make_cleanup ((make_cleanup_func) free, (void *) filename);
+ /* Have a pathname: read the symbol file. */
+ symbol_file_command (filename, from_tty);
+
+ return 1;
+}
+#endif /* SVR4_SHARED_LIBS */
+
+/*
+
+ 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;
+
+ if (!solib_cleanup_queued)
+ {
+ make_run_cleanup (do_clear_solib, NULL);
+ solib_cleanup_queued = 1;
+ }
+
+ }
+ 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)
+ {
+ warning ("find_solib: Can't read pathname for load map: %s\n",
+ safe_strerror (errcode));
+ return (so_list_next);
+ }
+ strncpy (new->so_name, buffer, MAX_PATH_SIZE - 1);
+ new->so_name[MAX_PATH_SIZE - 1] = '\0';
+ free (buffer);
+ catch_errors (solib_map_sections, new,
+ "Error while mapping shared library sections:\n",
+ RETURN_MASK_ALL);
+ }
+ }
+ return (so_list_next);
+}
+
+/* A small stub to get us past the arg-passing pinhole of catch_errors. */
+
+static int
+symbol_add_stub (arg)
+ PTR arg;
+{
+ register struct so_list *so = (struct so_list *) arg; /* catch_errs bogon */
+ CORE_ADDR text_addr = 0;
+
+ if (so->textsection)
+ text_addr = so->textsection->addr;
+ else if (so->abfd != NULL)
+ {
+ asection *lowest_sect;
+
+ /* If we didn't find a mapped non zero sized .text section, set up
+ text_addr so that the relocation in symbol_file_add does no harm. */
+
+ lowest_sect = bfd_get_section_by_name (so->abfd, ".text");
+ if (lowest_sect == NULL)
+ bfd_map_over_sections (so->abfd, find_lowest_section,
+ (PTR) &lowest_sect);
+ if (lowest_sect)
+ text_addr = bfd_section_vma (so->abfd, lowest_sect)
+ + (CORE_ADDR) LM_ADDR (so);
+ }
+
+ ALL_OBJFILES (so->objfile)
+ {
+ if (strcmp (so->objfile->name, so->so_name) == 0)
+ return 1;
+ }
+ so->objfile =
+ symbol_file_add (so->so_name, so->from_tty,
+ text_addr,
+ 0, 0, 0, 0, 1);
+ 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;
+
+#ifdef SVR4_SHARED_LIBS
+ /* If we are attaching to a running process for which we
+ have not opened a symbol file, we may be able to get its
+ symbols now! */
+ if (attach_flag &&
+ symfile_objfile == NULL)
+ catch_errors (open_symbol_file_object, (PTR) from_tty,
+ "Error reading attached process's symbol file.\n",
+ RETURN_MASK_ALL);
+
+#endif SVR4_SHARED_LIBS
+
+ 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)
+ {
+
+ /* Add these section table entries to the target's table. */
+ old = target_resize_to_sections (target, count);
+ 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, 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;
+ int addr_width;
+ char *addr_fmt;
+
+ if (exec_bfd == NULL)
+ {
+ printf_unfiltered ("No exec file.\n");
+ return;
+ }
+
+#ifndef TARGET_ELF64
+ addr_width = 8 + 4;
+ addr_fmt = "08l";
+#else
+ addr_width = 16 + 4;
+ addr_fmt = "016l";
+#endif
+
+ while ((so = find_solib (so)) != NULL)
+ {
+ if (so->so_name[0])
+ {
+ if (!header_done)
+ {
+ printf_unfiltered ("%-*s%-*s%-12s%s\n", addr_width, "From",
+ addr_width, "To", "Syms Read",
+ "Shared Object Library");
+ header_done++;
+ }
+
+ printf_unfiltered ("%-*s", addr_width,
+ local_hex_string_custom ((unsigned long) LM_ADDR (so),
+ addr_fmt));
+ printf_unfiltered ("%-*s", addr_width,
+ local_hex_string_custom ((unsigned long) so->lmend,
+ addr_fmt));
+ 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
+
+ char * 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.
+ */
+
+char *
+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 (so->so_name);
+ }
+ }
+ return (0);
+}
+
+/* Called by free_all_symtabs */
+
+void
+clear_solib ()
+{
+ struct so_list *next;
+ char *bfd_filename;
+
+ /* This function is expected to handle ELF shared libraries. It is
+ also used on Solaris, which can run either ELF or a.out binaries
+ (for compatibility with SunOS 4), both of which can use shared
+ libraries. So we don't know whether we have an ELF executable or
+ an a.out executable until the user chooses an executable file.
+
+ ELF shared libraries don't get mapped into the address space
+ until after the program starts, so we'd better not try to insert
+ breakpoints in them immediately. We have to wait until the
+ dynamic linker has loaded them; we'll hit a bp_shlib_event
+ breakpoint (look for calls to create_solib_event_breakpoint) when
+ it's ready.
+
+ SunOS shared libraries seem to be different --- they're present
+ as soon as the process begins execution, so there's no need to
+ put off inserting breakpoints. There's also nowhere to put a
+ bp_shlib_event breakpoint, so if we put it off, we'll never get
+ around to it.
+
+ So: disable breakpoints only if we're using ELF shared libs. */
+ if (exec_bfd != NULL
+ && bfd_get_flavour (exec_bfd) != bfd_target_aout_flavour)
+ disable_breakpoints_in_shlibs (1);
+
+ 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;
+}
+
+static void
+do_clear_solib (dummy)
+ PTR dummy;
+{
+ solib_cleanup_queued = 0;
+ clear_solib ();
+}
+
+#ifdef SVR4_SHARED_LIBS
+
+/* Return 1 if PC lies in the dynamic symbol resolution code of the
+ SVR4 run time loader. */
+
+static CORE_ADDR interp_text_sect_low;
+static CORE_ADDR interp_text_sect_high;
+static CORE_ADDR interp_plt_sect_low;
+static CORE_ADDR interp_plt_sect_high;
+
+int
+in_svr4_dynsym_resolve_code (pc)
+ CORE_ADDR pc;
+{
+ return ((pc >= interp_text_sect_low && pc < interp_text_sect_high)
+ || (pc >= interp_plt_sect_low && pc < interp_plt_sect_high)
+ || in_plt_section (pc, NULL));
+}
+#endif
+
+/*
+
+ 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.
+
+ */
+
+#ifndef SVR4_SHARED_LIBS
+
+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);
+}
+
+#endif /* #ifdef SVR4_SHARED_LIBS */
+
+/*
+
+ 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;
+ 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
+ interp_text_sect_low = interp_text_sect_high = 0;
+ interp_plt_sect_low = 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;
+ CORE_ADDR load_addr;
+ bfd *tmp_bfd;
+ CORE_ADDR sym_addr = 0;
+
+ /* 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 GNU/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;
+
+ /* Record the relocated start and end address of the dynamic linker
+ text and plt section for in_svr4_dynsym_resolve_code. */
+ interp_sect = bfd_get_section_by_name (tmp_bfd, ".text");
+ if (interp_sect)
+ {
+ interp_text_sect_low =
+ bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
+ interp_text_sect_high =
+ interp_text_sect_low + bfd_section_size (tmp_bfd, interp_sect);
+ }
+ interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt");
+ if (interp_sect)
+ {
+ interp_plt_sect_low =
+ bfd_section_vma (tmp_bfd, interp_sect) + load_addr;
+ interp_plt_sect_high =
+ interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
+ }
+
+ /* Now try to set a breakpoint in the dynamic linker. */
+ for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++)
+ {
+ sym_addr = bfd_lookup_symbol (tmp_bfd, *bkpt_namep);
+ if (sym_addr != 0)
+ break;
+ }
+
+ /* We're done with the temporary bfd. */
+ bfd_close (tmp_bfd);
+
+ if (sym_addr != 0)
+ {
+ create_solib_event_breakpoint (load_addr + sym_addr);
+ 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.\nGDB will be unable to debug shared library initializers\nand 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, NULL, symfile_objfile);
+ if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
+ {
+ create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol));
+ return 1;
+ }
+ }
+
+ /* Nothing good happened. */
+ success = 0;
+
+#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;
+ }
+
+#if !defined(SVR4_SHARED_LIBS) || defined(_SCO_DS)
+ /* SCO and SunOS need 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. */
+
+ 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;
+
+#if !defined(_SCO_DS)
+ /* 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)
+ solib_add ((char *) 0, 0, (struct target_ops *) 0);
+#endif /* ! _SCO_DS */
+#endif
+}
+
+/*
+
+ 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);
+}
+
+#endif /* HAVE_LINK_H */
+
+void
+_initialize_solib ()
+{
+#ifdef HAVE_LINK_H
+
+ 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,
+ "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);
+
+ add_show_from_set
+ (add_set_cmd ("solib-absolute-prefix", class_support, var_filename,
+ (char *) &solib_absolute_prefix,
+ "Set prefix for loading absolute shared library symbol files.\n\
+For other (relative) files, you can add values using `set solib-search-path'.",
+ &setlist),
+ &showlist);
+ add_show_from_set
+ (add_set_cmd ("solib-search-path", class_support, var_string,
+ (char *) &solib_search_path,
+ "Set the search path for loading non-absolute shared library symbol files.\n\
+This takes precedence over the environment variables PATH and LD_LIBRARY_PATH.",
+ &setlist),
+ &showlist);
+#endif /* HAVE_LINK_H */
}
projects / deliverable / binutils-gdb.git / blobdiff