objfiles.c   [plain text]

/* GDB routines for manipulating objfiles.

   Copyright 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   2001, 2002 Free Software Foundation, Inc.

   Contributed by Cygnus Support, using pieces from other GDB modules.

   This file is part of GDB.

   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.

   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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/* This file contains support routines for creating, manipulating, and
   destroying objfile structures. */

#include "defs.h"
#include "bfd.h"		/* Binary File Description */
#include "symtab.h"
#include "symfile.h"
#include "objfiles.h"
#include "gdb-stabs.h"
#include "target.h"
#include "gdbcmd.h"
#include "bcache.h"

#include <sys/types.h>
#include "gdb_stat.h"
#include <fcntl.h>
#include "gdb_obstack.h"
#include "gdb_string.h"
#include "buildsym.h"
#include "breakpoint.h"

/* Prototypes for local functions */

#if defined(USE_MMALLOC) && defined(HAVE_MMAP)

#include "mmalloc.h"

static int open_existing_mapped_file (char *, long, int);

static int open_mapped_file (char *filename, long mtime, int flags);

static void *map_to_file (int);

#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */

static void add_to_objfile_sections (bfd *, sec_ptr, void *);

static void objfile_remove_from_restrict_list (struct objfile *);

/* Externally visible variables that are owned by this module.
   See declarations in objfile.h for more info. */

#ifndef TEXT_SECTION_NAME
#define TEXT_SECTION_NAME ".text"
#endif

#ifndef DATA_SECTION_NAME
#define DATA_SECTION_NAME ".data"
#endif

struct objfile *object_files;	/* Linked list of all objfiles */
struct objfile *current_objfile;	/* For symbol file being read in */
struct objfile *symfile_objfile;	/* Main symbol table loaded from */
struct objfile *rt_common_objfile;	/* For runtime common symbols */

int mapped_symbol_files = 0;
int use_mapped_symbol_files = 1;

#ifdef FSF_OBJFILES
/* Locate all mappable sections of a BFD file. 
   objfile_p_char is a char * to get it through
   bfd_map_over_sections; we cast it back to its proper type.  */

#ifndef TARGET_KEEP_SECTION
#define TARGET_KEEP_SECTION(ASECT)	0
#endif

/* Called via bfd_map_over_sections to build up the section table that
   the objfile references.  The objfile contains pointers to the start
   of the table (objfile->sections) and to the first location after
   the end of the table (objfile->sections_end). */

static void
add_to_objfile_sections (bfd *abfd, sec_ptr asect, void *objfile_p_char)
{
  struct objfile *objfile = (struct objfile *) objfile_p_char;
  struct obj_section section;
  flagword aflag;

  aflag = bfd_get_section_flags (abfd, asect);

  if (!(aflag & SEC_ALLOC) && !(TARGET_KEEP_SECTION (asect)))
    return;

  if (0 == bfd_section_size (abfd, asect))
    return;
  section.offset = 0;
  section.objfile = objfile;
  section.the_bfd_section = asect;
  section.ovly_mapped = 0;
  section.addr = bfd_section_vma (abfd, asect);
  section.endaddr = section.addr + bfd_section_size (abfd, asect);
  obstack_grow (&objfile->psymbol_obstack, (char *) &section, sizeof (section));
  objfile->sections_end = (struct obj_section *) (((unsigned long) objfile->sections_end) + 1);
}

/* Builds a section table for OBJFILE.
   Returns 0 if OK, 1 on error (in which case bfd_error contains the
   error).

   Note that while we are building the table, which goes into the
   psymbol obstack, we hijack the sections_end pointer to instead hold
   a count of the number of sections.  When bfd_map_over_sections
   returns, this count is used to compute the pointer to the end of
   the sections table, which then overwrites the count.

   Also note that the OFFSET and OVLY_MAPPED in each table entry
   are initialized to zero.

   Also note that if anything else writes to the psymbol obstack while
   we are building the table, we're pretty much hosed. */

int
build_objfile_section_table (struct objfile *objfile)
{
  /* objfile->sections can be already set when reading a mapped symbol
     file.  I believe that we do need to rebuild the section table in
     this case (we rebuild other things derived from the bfd), but we
     can't free the old one (it's in the psymbol_obstack).  So we just
     waste some memory.  */

  objfile->sections_end = 0;
  bfd_map_over_sections (objfile->obfd, add_to_objfile_sections, (char *) objfile);
  objfile->sections = (struct obj_section *)
    obstack_finish (&objfile->psymbol_obstack);
  objfile->sections_end = objfile->sections + (unsigned long) objfile->sections_end;
  return (0);
}

/* Given a pointer to an initialized bfd (ABFD) and some flag bits
   allocate a new objfile struct, fill it in as best we can, link it
   into the list of all known objfiles, and return a pointer to the
   new objfile struct.

   The FLAGS word contains various bits (OBJF_*) that can be taken as
   requests for specific operations, like trying to open a mapped
   version of the objfile (OBJF_MAPPED).  Other bits like
   OBJF_SHARED are simply copied through to the new objfile flags
   member. */

struct objfile *
allocate_objfile (bfd *abfd, int flags)
{
  struct objfile *objfile = NULL;

  if (mapped_symbol_files)
    flags |= OBJF_MAPPED;

#if defined(USE_MMALLOC) && defined(HAVE_MMAP)
  if (abfd != NULL)
    {

      /* If we can support mapped symbol files, try to open/reopen the
         mapped file that corresponds to the file from which we wish to
         read symbols.  If the objfile is to be mapped, we must malloc
         the structure itself using the mmap version, and arrange that
         all memory allocation for the objfile uses the mmap routines.
         If we are reusing an existing mapped file, from which we get
         our objfile pointer, we have to make sure that we update the
         pointers to the alloc/free functions in the obstack, in case
         these functions have moved within the current gdb.  */

      int fd;

      fd = open_mapped_file (bfd_get_filename (abfd), bfd_get_mtime (abfd),
			     flags);
      if (fd >= 0)
	{
	  void *md;

	  if ((md = map_to_file (fd)) == NULL)
	    {
	      close (fd);
	    }
	  else if ((objfile = (struct objfile *) mmalloc_getkey (md, 0)) != NULL)
	    {
	      /* Update memory corruption handler function addresses. */
	      init_malloc (md);
	      objfile->md = md;
	      objfile->mmfd = fd;
	      /* Update pointers to functions to *our* copies */
	      obstack_chunkfun (&objfile->psymbol_cache.cache, xmmalloc);
	      obstack_freefun (&objfile->psymbol_cache.cache, xmfree);
	      obstack_chunkfun (&objfile->macro_cache.cache, xmmalloc);
	      obstack_freefun (&objfile->macro_cache.cache, xmfree);
	      obstack_chunkfun (&objfile->psymbol_obstack, xmmalloc);
	      obstack_freefun (&objfile->psymbol_obstack, xmfree);
	      obstack_chunkfun (&objfile->symbol_obstack, xmmalloc);
	      obstack_freefun (&objfile->symbol_obstack, xmfree);
	      obstack_chunkfun (&objfile->type_obstack, xmmalloc);
	      obstack_freefun (&objfile->type_obstack, xmfree);
	      /* If already in objfile list, unlink it. */
	      unlink_objfile (objfile);
	      /* Forget things specific to a particular gdb, may have changed. */
	      objfile->sf = NULL;
	    }
	  else
	    {

	      /* Set up to detect internal memory corruption.  MUST be
	         done before the first malloc.  See comments in
	         init_malloc() and mmcheck().  */

	      init_malloc (md);

	      objfile = (struct objfile *)
		xmmalloc (md, sizeof (struct objfile));
	      memset (objfile, 0, sizeof (struct objfile));
	      objfile->md = md;
	      objfile->mmfd = fd;
	      objfile->flags |= OBJF_MAPPED;
	      mmalloc_setkey (objfile->md, 0, objfile);
	      obstack_specify_allocation_with_arg (&objfile->psymbol_cache.cache,
						   0, 0, xmmalloc, xmfree,
						   objfile->md);
	      obstack_specify_allocation_with_arg (&objfile->macro_cache.cache,
						   0, 0, xmmalloc, xmfree,
						   objfile->md);
	      obstack_specify_allocation_with_arg (&objfile->psymbol_obstack,
						   0, 0, xmmalloc, xmfree,
						   objfile->md);
	      obstack_specify_allocation_with_arg (&objfile->symbol_obstack,
						   0, 0, xmmalloc, xmfree,
						   objfile->md);
	      obstack_specify_allocation_with_arg (&objfile->type_obstack,
						   0, 0, xmmalloc, xmfree,
						   objfile->md);
	    }
	}

      if ((flags & OBJF_MAPPED) && (objfile == NULL))
	{
	  warning ("symbol table for '%s' will not be mapped",
		   bfd_get_filename (abfd));
	  flags &= ~OBJF_MAPPED;
	}
    }
#else /* !defined(USE_MMALLOC) || !defined(HAVE_MMAP) */

  if (flags & OBJF_MAPPED)
    {
      warning ("mapped symbol tables are not supported on this machine; missing or broken mmap().");

      /* Turn off the global flag so we don't try to do mapped symbol tables
         any more, which shuts up gdb unless the user specifically gives the
         "mapped" keyword again. */

      mapped_symbol_files = 0;
      flags &= ~OBJF_MAPPED;
    }

#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */

  /* If we don't support mapped symbol files, didn't ask for the file to be
     mapped, or failed to open the mapped file for some reason, then revert
     back to an unmapped objfile. */

  if (objfile == NULL)
    {
      objfile = (struct objfile *) xmalloc (sizeof (struct objfile));
      memset (objfile, 0, sizeof (struct objfile));
      objfile->md = NULL;
      objfile->psymbol_cache = bcache_xmalloc (NULL);
      objfile->macro_cache = bcache_xmalloc (NULL);
      obstack_specify_allocation (&objfile->psymbol_obstack, 0, 0, xmalloc,
				  xfree);
      obstack_specify_allocation (&objfile->symbol_obstack, 0, 0, xmalloc,
				  xfree);
      obstack_specify_allocation (&objfile->type_obstack, 0, 0, xmalloc,
				  xfree);
      flags &= ~OBJF_MAPPED;
    }

  /* Update the per-objfile information that comes from the bfd, ensuring
     that any data that is reference is saved in the per-objfile data
     region. */

  objfile->obfd = abfd;
  if (objfile->name != NULL)
    {
      xmfree (objfile->md, objfile->name);
    }
  if (abfd != NULL)
    {
      objfile->name = mstrsave (objfile->md, bfd_get_filename (abfd));
      objfile->mtime = bfd_get_mtime (abfd);

      /* Build section table.  */

      if (build_objfile_section_table (objfile))
	{
	  error ("Can't find the file sections in `%s': %s",
		 objfile->name, bfd_errmsg (bfd_get_error ()));
	}
    }

  /* Initialize the section indexes for this objfile, so that we can
     later detect if they are used w/o being properly assigned to. */

    objfile->sect_index_text = -1;
    objfile->sect_index_data = -1;
    objfile->sect_index_bss = -1;
    objfile->sect_index_rodata = -1;

  /* Save passed in flag bits. */
  objfile->flags |= flags;
  objfile->symflags = -1;

  link_objfile (objfile);

  return (objfile);
}
#endif /* FSF_OBJFILES */

/* Put one object file before a specified on in the global list.
   This can be used to make sure an object file is destroyed before
   another when using ALL_OBJFILES_SAFE to free all objfiles. */
void
put_objfile_before (struct objfile *objfile, struct objfile *before_this)
{
  struct objfile **objp;

  unlink_objfile (objfile);
  
  for (objp = &object_files; *objp != NULL; objp = &((*objp)->next))
    {
      if (*objp == before_this)
	{
	  objfile->next = *objp;
	  *objp = objfile;
	  return;
	}
    }
  
  internal_error (__FILE__, __LINE__,
		  "put_objfile_before: before objfile not in list");
}

/* Put OBJFILE at the front of the list.  */

void
objfile_to_front (struct objfile *objfile)
{
  struct objfile **objp;
  for (objp = &object_files; *objp != NULL; objp = &((*objp)->next))
    {
      if (*objp == objfile)
	{
	  /* Unhook it from where it is.  */
	  *objp = objfile->next;
	  /* Put it in the front.  */
	  objfile->next = object_files;
	  object_files = objfile;
	  break;
	}
    }
}

/* Link OBJFILE into the list of known objfiles.  It is an error if
   OBJFILE has a non-zero NEXT pointer before being inserted. */

void
link_objfile (struct objfile *objfile)
{
  struct objfile *last_one = NULL;

  if (objfile->next != NULL)
    internal_error (__FILE__, __LINE__,
		    "unlink_objfile: objfile already linked");

  /* 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;
    }
}

/* Unlink OBJFILE from the list of known objfiles, clearing its NEXT
   pointer.  It is an error if OBJFILE is not on the list of known
   objfiles. */

void
unlink_objfile (struct objfile *objfile)
{
  struct objfile **objpp;

  for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp)->next))
    {
      if (*objpp == objfile)
	{
	  *objpp = (*objpp)->next;
	  objfile->next = NULL;
	  return;
	}
    }

  internal_error (__FILE__, __LINE__,
		  "unlink_objfile: objfile already unlinked");
}


/* Destroy an objfile and all the symtabs and psymtabs under it.  Note
   that as much as possible is allocated on the symbol_obstack and
   psymbol_obstack, so that the memory can be efficiently freed.

   Things which we do NOT free because they are not in malloc'd memory
   or not in memory specific to the objfile include:

   objfile -> sf

   FIXME:  If the objfile is using reusable symbol information (via mmalloc),
   then we need to take into account the fact that more than one process
   may be using the symbol information at the same time (when mmalloc is
   extended to support cooperative locking).  When more than one process
   is using the mapped symbol info, we need to be more careful about when
   we free objects in the reusable area. */

void
free_objfile (struct objfile *objfile)
{
  if (objfile->separate_debug_objfile)
    {
      free_objfile (objfile->separate_debug_objfile);
    }
  
  if (objfile->separate_debug_objfile_backlink)
    {
      /* We freed the separate debug file, make sure the base objfile
	 doesn't reference it.  */
      objfile->separate_debug_objfile_backlink->separate_debug_objfile = NULL;
    }
  
  /* First do any symbol file specific actions required when we are
     finished with a particular symbol file.  Note that if the objfile
     is using reusable symbol information (via mmalloc) then each of
     these routines is responsible for doing the correct thing, either
     freeing things which are valid only during this particular gdb
     execution, or leaving them to be reused during the next one. */

  if (objfile->sf != NULL)
    {
      (*objfile->sf->sym_finish) (objfile);
    }

  /* We always close the bfd. */

  if (objfile->obfd != NULL)
    {
      char *name = bfd_get_filename (objfile->obfd);
      if (!bfd_close (objfile->obfd))
	warning ("cannot close \"%s\": %s",
		 name, bfd_errmsg (bfd_get_error ()));
      xfree (name);
    }

  /* Remove it from the chain of all objfiles. */

  unlink_objfile (objfile);

  /* Remove it from the chain of restricted objfiles. */

  objfile_remove_from_restrict_list (objfile);

  /* If we are going to free the runtime common objfile, mark it
     as unallocated.  */

  if (objfile == rt_common_objfile)
    rt_common_objfile = NULL;

  /* Before the symbol table code was redone to make it easier to
     selectively load and remove information particular to a specific
     linkage unit, gdb used to do these things whenever the monolithic
     symbol table was blown away.  How much still needs to be done
     is unknown, but we play it safe for now and keep each action until
     it is shown to be no longer needed. */

  /* I *think* all our callers call clear_symtab_users.  If so, no need
     to call this here.  */
  clear_pc_function_cache ();

  /* The last thing we do is free the objfile struct itself for the
     non-reusable case, or detach from the mapped file for the
     reusable case.  Note that the mmalloc_detach or the xmfree() is
     the last thing we can do with this objfile. */

#if defined(USE_MMALLOC) && defined(HAVE_MMAP)

  if (objfile->flags & OBJF_MAPPED)
    {
      /* Remember the fd so we can close it.  We can't close it before
         doing the detach, and after the detach the objfile is gone. */
      int mmfd;

      mmfd = objfile->mmfd;
      mmalloc_detach (objfile->md);
      objfile = NULL;
      close (mmfd);
    }

#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */

  /* If we still have an objfile, then either we don't support reusable
     objfiles or this one was not reusable.  So free it normally. */

  if (objfile != NULL)
    {
      if (objfile->name != NULL)
	{
	  xmfree (objfile->md, objfile->name);
	}
      if (objfile->global_psymbols.list)
	xmfree (objfile->md, objfile->global_psymbols.list);
      if (objfile->static_psymbols.list)
	xmfree (objfile->md, objfile->static_psymbols.list);
      /* Free the obstacks for non-reusable objfiles */
      bcache_xfree (objfile->psymbol_cache);
      bcache_xfree (objfile->macro_cache);
      obstack_free (&objfile->psymbol_obstack, 0);
      obstack_free (&objfile->symbol_obstack, 0);
      obstack_free (&objfile->type_obstack, 0);
      xmfree (objfile->md, objfile);
      objfile = NULL;
    }
}

static void
do_free_objfile_cleanup (void *obj)
{
  free_objfile (obj);
}

struct cleanup *
make_cleanup_free_objfile (struct objfile *obj)
{
  return make_cleanup (do_free_objfile_cleanup, obj);
}

/* Free all the object files at once and clean up their users.  */

void
free_all_objfiles (void)
{
  struct objfile *objfile, *temp;

  ALL_OBJFILES_SAFE (objfile, temp)
  {
    free_objfile (objfile);
  }
  clear_symtab_users ();
}

/* Relocate OBJFILE to NEW_OFFSETS.  There should be OBJFILE->NUM_SECTIONS
   entries in new_offsets.  */
void
objfile_relocate (struct objfile *objfile, struct section_offsets *new_offsets)
{
  struct section_offsets *delta =
    (struct section_offsets *) alloca (SIZEOF_SECTION_OFFSETS);

  {
    int i;
    int something_changed = 0;
    for (i = 0; i < objfile->num_sections; ++i)
      {
	delta->offsets[i] =
	  ANOFFSET (new_offsets, i) - ANOFFSET (objfile->section_offsets, i);
	if (ANOFFSET (delta, i) != 0)
	  something_changed = 1;
      }
    if (!something_changed)
      return;
  }

  /* OK, get all the symtabs.  */
  {
    struct symtab *s;

    ALL_OBJFILE_SYMTABS (objfile, s)
    {
      struct linetable *l;
      struct blockvector *bv;
      int i;

      /* First the line table.  */
      l = LINETABLE (s);
      if (l)
	{
	  unsigned int num_discontinuities = 0;
	  int discontinuity_index = -1;

	  for (i = 0; i < l->nitems; ++i)
	    l->item[i].pc += ANOFFSET (delta, s->block_line_section);

	  /* Re-sort the line-table.  The table should have started
	     off sorted, so we should be able to re-sort it by
	     rotating the values in the buffer.  */

	  for (i = 0; i < (l->nitems - 1); ++i)
	    if (l->item[i].pc > l->item[i + 1].pc)
	      {
		num_discontinuities++;
		discontinuity_index = i + 1;
	      }
	  
	  if (num_discontinuities == 1)
	    {
	      struct linetable *new_linetable = NULL;
	      size_t size = ((l->nitems - 1) * sizeof (struct linetable_entry))
		+ sizeof (struct linetable);
	      
	      new_linetable = (struct linetable *) xmalloc (size);
	      memcpy (new_linetable, l, sizeof (struct linetable));
	      memcpy (new_linetable->item,
		      l->item + discontinuity_index,
		      (l->nitems - discontinuity_index) * sizeof (struct linetable_entry));
	      memcpy (new_linetable->item + (l->nitems - discontinuity_index),
		      l->item,
		      discontinuity_index * sizeof (struct linetable_entry));
	      memcpy (l->item, new_linetable->item, l->nitems * sizeof (struct linetable_entry));

	      xfree (new_linetable);
	    }
	  else if (num_discontinuities > 0)
	    {
	      warning ("line table was not properly sorted; re-sorting");
	      qsort (l->item, l->nitems, sizeof (struct linetable_entry), compare_line_numbers);
	    }
	}
      
      /* Don't relocate a shared blockvector more than once.  */
      if (!s->primary)
	continue;

      bv = BLOCKVECTOR (s);
      for (i = 0; i < BLOCKVECTOR_NBLOCKS (bv); ++i)
	{
	  struct block *b;
	  struct symbol *sym;
	  int j;

	  b = BLOCKVECTOR_BLOCK (bv, i);
	  BLOCK_START (b) += ANOFFSET (delta, s->block_line_section);
	  BLOCK_END (b) += ANOFFSET (delta, s->block_line_section);

	  ALL_BLOCK_SYMBOLS (b, j, sym)
	    {
	      fixup_symbol_section (sym, objfile);

	      /* The RS6000 code from which this was taken skipped
	         any symbols in STRUCT_NAMESPACE or UNDEF_NAMESPACE.
	         But I'm leaving out that test, on the theory that
	         they can't possibly pass the tests below.  */
	      if ((SYMBOL_CLASS (sym) == LOC_LABEL
		   || SYMBOL_CLASS (sym) == LOC_STATIC
		   || SYMBOL_CLASS (sym) == LOC_INDIRECT)
		  && SYMBOL_SECTION (sym) >= 0)
		{
		  SYMBOL_VALUE_ADDRESS (sym) +=
		    ANOFFSET (delta, SYMBOL_SECTION (sym));
		}
#ifdef MIPS_EFI_SYMBOL_NAME
	      /* Relocate Extra Function Info for ecoff.  */

	      else if (SYMBOL_CLASS (sym) == LOC_CONST
		       && SYMBOL_NAMESPACE (sym) == LABEL_NAMESPACE
		       && strcmp (SYMBOL_NAME (sym), MIPS_EFI_SYMBOL_NAME) == 0)
		ecoff_relocate_efi (sym, ANOFFSET (delta,
						   s->block_line_section));
#endif
	    }
	}
    }
  }

  {
    struct partial_symtab *p;

    ALL_OBJFILE_PSYMTABS (objfile, p)
    {
      p->textlow += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
      p->texthigh += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
    }
  }

  {
    struct partial_symbol **psym;

    for (psym = objfile->global_psymbols.list;
	 psym < objfile->global_psymbols.next;
	 psym++)
      {
	fixup_psymbol_section (*psym, objfile);
	if (SYMBOL_SECTION (*psym) >= 0)
	  SYMBOL_VALUE_ADDRESS (*psym) += ANOFFSET (delta,
						    SYMBOL_SECTION (*psym));
      }
    for (psym = objfile->static_psymbols.list;
	 psym < objfile->static_psymbols.next;
	 psym++)
      {
	fixup_psymbol_section (*psym, objfile);
	if (SYMBOL_SECTION (*psym) >= 0)
	  SYMBOL_VALUE_ADDRESS (*psym) += ANOFFSET (delta,
						    SYMBOL_SECTION (*psym));
      }
  }

  {
    struct minimal_symbol *msym;
    ALL_OBJFILE_MSYMBOLS (objfile, msym)
      if (SYMBOL_SECTION (msym) >= 0)
      SYMBOL_VALUE_ADDRESS (msym) += ANOFFSET (delta, SYMBOL_SECTION (msym));
  }
  /* Relocating different sections by different amounts may cause the symbols
     to be out of order.  */
  msymbols_sort (objfile);

  {
    int i;
    for (i = 0; i < objfile->num_sections; ++i)
      (objfile->section_offsets)->offsets[i] = ANOFFSET (new_offsets, i);
  }

  if (objfile->ei.entry_point != ~(CORE_ADDR) 0)
    {
      /* Relocate ei.entry_point with its section offset, use SECT_OFF_TEXT
	 only as a fallback.  */
      struct obj_section *s;
      s = find_pc_section (objfile->ei.entry_point);
      if (s)
        objfile->ei.entry_point += ANOFFSET (delta, s->the_bfd_section->index);
      else
        objfile->ei.entry_point += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
    }

  {
    struct obj_section *s;
    bfd *abfd;

    abfd = objfile->obfd;

    ALL_OBJFILE_OSECTIONS (objfile, s)
      {
      	int idx = s->the_bfd_section->index;
	
	s->addr += ANOFFSET (delta, idx);
	s->endaddr += ANOFFSET (delta, idx);
      }
  }

  if (objfile->ei.entry_func_lowpc != INVALID_ENTRY_LOWPC)
    {
      objfile->ei.entry_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
      objfile->ei.entry_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
    }

  if (objfile->ei.entry_file_lowpc != INVALID_ENTRY_LOWPC)
    {
      objfile->ei.entry_file_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
      objfile->ei.entry_file_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
    }

  if (objfile->ei.main_func_lowpc != INVALID_ENTRY_LOWPC)
    {
      objfile->ei.main_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
      objfile->ei.main_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile));
    }

  /* Relocate breakpoints as necessary, after things are relocated. */
  breakpoint_re_set (objfile);
}

/* Many places in gdb want to test just to see if we have any partial
   symbols available.  This function returns zero if none are currently
   available, nonzero otherwise. */

int
have_partial_symbols (void)
{
  struct objfile *ofp;

  ALL_OBJFILES (ofp)
  {
    if (ofp->psymtabs != NULL)
      {
	return 1;
      }
  }
  return 0;
}

/* Many places in gdb want to test just to see if we have any full
   symbols available.  This function returns zero if none are currently
   available, nonzero otherwise. */

int
have_full_symbols (void)
{
  struct objfile *ofp;

  ALL_OBJFILES (ofp)
  {
    if (ofp->symtabs != NULL)
      {
	return 1;
      }
  }
  return 0;
}


/* This operations deletes all objfile entries that represent solibs that
   weren't explicitly loaded by the user, via e.g., the add-symbol-file
   command.
 */
void
objfile_purge_solibs (void)
{
  struct objfile *objf;
  struct objfile *temp;

  ALL_OBJFILES_SAFE (objf, temp)
  {
    /* We assume that the solib package has been purged already, or will
       be soon.
     */
#ifdef NM_MACOSX
    /* not now --- the dyld code handles this better; and this will really make it upset */
    if (!(objf->flags & OBJF_USERLOADED) && (objf->flags & OBJF_SHARED))
      free_objfile (objf);
#endif
  }
}


/* Many places in gdb want to test just to see if we have any minimal
   symbols available.  This function returns zero if none are currently
   available, nonzero otherwise. */

int
have_minimal_symbols (void)
{
  struct objfile *ofp;

  ALL_OBJFILES (ofp)
  {
    if (ofp->msymbols != NULL)
      {
	return 1;
      }
  }
  return 0;
}

#ifdef FSF_OBJFILES
#if defined(USE_MMALLOC) && defined(HAVE_MMAP)

/* Given the name of a mapped symbol file in SYMSFILENAME, and the timestamp
   of the corresponding symbol file in MTIME, try to open an existing file
   with the name SYMSFILENAME and verify it is more recent than the base
   file by checking it's timestamp against MTIME.

   If SYMSFILENAME does not exist (or can't be stat'd), simply returns -1.

   If SYMSFILENAME does exist, but is out of date, we check to see if the
   user has specified creation of a mapped file.  If so, we don't issue
   any warning message because we will be creating a new mapped file anyway,
   overwriting the old one.  If not, then we issue a warning message so that
   the user will know why we aren't using this existing mapped symbol file.
   In either case, we return -1.

   If SYMSFILENAME does exist and is not out of date, but can't be opened for
   some reason, then prints an appropriate system error message and returns -1.

   Otherwise, returns the open file descriptor.  */

static int
open_existing_mapped_file (char *symsfilename, long mtime, int flags)
{
  int fd = -1;
  struct stat sbuf;

  if (stat (symsfilename, &sbuf) == 0)
    {
      if (sbuf.st_mtime < mtime)
	{
	  if (!(flags & OBJF_MAPPED))
	    {
	      warning ("mapped symbol file `%s' is out of date, ignored it",
		       symsfilename);
	    }
	}
      else if ((fd = open (symsfilename, O_RDWR)) < 0)
	{
	  if (error_pre_print)
	    {
	      printf_unfiltered (error_pre_print);
	    }
	  print_sys_errmsg (symsfilename, errno);
	}
    }
  return (fd);
}

/* Look for a mapped symbol file that corresponds to FILENAME and is more
   recent than MTIME.  If MAPPED is nonzero, the user has asked that gdb
   use a mapped symbol file for this file, so create a new one if one does
   not currently exist.

   If found, then return an open file descriptor for the file, otherwise
   return -1.

   This routine is responsible for implementing the policy that generates
   the name of the mapped symbol file from the name of a file containing
   symbols that gdb would like to read.  Currently this policy is to append
   ".syms" to the name of the file.

   This routine is also responsible for implementing the policy that
   determines where the mapped symbol file is found (the search path).
   This policy is that when reading an existing mapped file, a file of
   the correct name in the current directory takes precedence over a
   file of the correct name in the same directory as the symbol file.
   When creating a new mapped file, it is always created in the current
   directory.  This helps to minimize the chances of a user unknowingly
   creating big mapped files in places like /bin and /usr/local/bin, and
   allows a local copy to override a manually installed global copy (in
   /bin for example).  */

static int
open_mapped_file (char *filename, long mtime, int flags)
{
  int fd;
  char *symsfilename;

  /* First try to open an existing file in the current directory, and
     then try the directory where the symbol file is located. */

  symsfilename = concat ("./", lbasename (filename), ".syms", (char *) NULL);
  if ((fd = open_existing_mapped_file (symsfilename, mtime, flags)) < 0)
    {
      xfree (symsfilename);
      symsfilename = concat (filename, ".syms", (char *) NULL);
      fd = open_existing_mapped_file (symsfilename, mtime, flags);
    }

  /* If we don't have an open file by now, then either the file does not
     already exist, or the base file has changed since it was created.  In
     either case, if the user has specified use of a mapped file, then
     create a new mapped file, truncating any existing one.  If we can't
     create one, print a system error message saying why we can't.

     By default the file is rw for everyone, with the user's umask taking
     care of turning off the permissions the user wants off. */

  if ((fd < 0) && (flags & OBJF_MAPPED))
    {
      xfree (symsfilename);
      symsfilename = concat ("./", lbasename (filename), ".syms",
			     (char *) NULL);
      if ((fd = open (symsfilename, O_RDWR | O_CREAT | O_TRUNC, 0666)) < 0)
	{
	  if (error_pre_print)
	    {
	      printf_unfiltered (error_pre_print);
	    }
	  print_sys_errmsg (symsfilename, errno);
	}
    }

  xfree (symsfilename);
  return (fd);
}

static void *
map_to_file (int fd)
{
  void *md;
  CORE_ADDR mapto;

  md = mmalloc_attach (fd, 0);
  if (md != NULL)
    {
      mapto = (CORE_ADDR) mmalloc_getkey (md, 1);
      md = mmalloc_detach (md);
      if (md != NULL)
	{
	  /* FIXME: should figure out why detach failed */
	  md = NULL;
	}
      else if (mapto != (CORE_ADDR) NULL)
	{
	  /* This mapping file needs to be remapped at "mapto" */
	  md = mmalloc_attach (fd, mapto);
	}
      else
	{
	  /* This is a freshly created mapping file. */
	  mapto = (CORE_ADDR) mmalloc_findbase (20 * 1024 * 1024);
	  if (mapto != 0)
	    {
	      /* To avoid reusing the freshly created mapping file, at the 
	         address selected by mmap, we must truncate it before trying
	         to do an attach at the address we want. */
	      ftruncate (fd, 0);
	      md = mmalloc_attach (fd, mapto);
	      if (md != NULL)
		{
		  mmalloc_setkey (md, 1, mapto);
		}
	    }
	}
    }
  return (md);
}

#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */
#endif /* FSF_OBJFILES */

/* Returns a section whose range includes PC and SECTION, 
   or NULL if none found.  Note the distinction between the return type, 
   struct obj_section (which is defined in gdb), and the input type
   struct sec (which is a bfd-defined data type).  The obj_section
   contains a pointer to the bfd struct sec section.  */

struct obj_section *
find_pc_sect_section (CORE_ADDR pc, struct sec *section)
{
  struct obj_section *s;
  struct objfile *objfile;

  ALL_OBJSECTIONS (objfile, s)
    if ((section == 0 || section == s->the_bfd_section) &&
	s->addr <= pc && pc < s->endaddr)
      return (s);

  return (NULL);
}

/* Returns a section whose range includes PC or NULL if none found. 
   Backward compatibility, no section.  */

struct obj_section *
find_pc_section (CORE_ADDR pc)
{
  return find_pc_sect_section (pc, find_pc_mapped_section (pc));
}


/* In SVR4, we recognize a trampoline by it's section name. 
   That is, if the pc is in a section named ".plt" then we are in
   a trampoline.  */

int
in_plt_section (CORE_ADDR pc, char *name)
{
  struct obj_section *s;
  int retval = 0;

  s = find_pc_section (pc);

  retval = (s != NULL
	    && s->the_bfd_section->name != NULL
	    && STREQ (s->the_bfd_section->name, ".plt"));
  return (retval);
}

/* Return nonzero if NAME is in the import list of OBJFILE.  Else
   return zero.  */

int
is_in_import_list (char *name, struct objfile *objfile)
{
  register int i;

  if (!objfile || !name || !*name)
    return 0;

  for (i = 0; i < objfile->import_list_size; i++)
    if (objfile->import_list[i] && STREQ (name, objfile->import_list[i]))
      return 1;
  return 0;
}

/* The _restrict_ functions are part of the mechanism to add
   an iterator to ALL_OBJFILES that can be used to restrict the
   search to newly added objfiles - in particular when breakpoints
   are being reinserted.

   These are non-nesting interators to be used in ALL_OBJFILES
   only.  If you want something fancier, you need to pass in an
   iterator token to get_first, and pass it back to get_next.  */

static struct objfile_list *objfile_list_ptr;
static int restrict_search = 0;
struct objfile_list *objfile_list;

/* Set the flag to tell ALL_OBJFILES whether to restrict the search or
   not. */

void 
objfile_restrict_search (int on)
{
  restrict_search = on;
}

/* Add an objfile to the restricted search list.  */

void
objfile_add_to_restrict_list (struct objfile *objfile)
{
  struct objfile_list *new_objfile = (struct objfile_list *)
    xmalloc (sizeof (struct objfile_list));
  new_objfile->next = objfile_list;
  new_objfile->objfile = objfile;
  objfile_list = new_objfile;
}

/* Remove an objfile from the restricted search list.  */

static void
objfile_remove_from_restrict_list (struct objfile *objfile)
{
  struct objfile_list **objpp;
  struct objfile_list *i;
  
  for (objpp = &objfile_list; *objpp != NULL; objpp = &((*objpp)->next))
    {
      if ((*objpp)->objfile == objfile)
        {
          i = *objpp;
          *objpp = (*objpp)->next;
          xfree (i);
          return;
        }
    }
}

/* Clear the restricted objfile search list.  */

void
objfile_clear_restrict_list ()
{
  while (objfile_list != NULL)
    {
      struct objfile_list *list_ptr;
      list_ptr = objfile_list;
      objfile_list = list_ptr->next;
      xfree (list_ptr);
    }
}

/* Get the first objfile.  If the restrict_search flag is set,
   this returns the first objfile in the restricted list, otherwise
   it starts from the object_files. */

struct objfile *
objfile_get_first ()
{
  if (!restrict_search || objfile_list == NULL)
    return object_files;
  else
    {
      objfile_list_ptr = objfile_list->next;
      return objfile_list->objfile;
    }
}

/* Get the next objfile in the list.  
   FIXME: Right now you can't nest calls to ALL_OBJFILES if 
   restrict_search is on.  This isn't a problem in practice,
   but is ugly.  */

struct objfile *
objfile_get_next (struct objfile *in_objfile)
{
  struct objfile *objfile;
  
  if (!restrict_search || objfile_list == NULL)
    {
      if (in_objfile)
	return in_objfile->next;
      else
	return NULL;
    }

  if (objfile_list_ptr == NULL)
    {
      return NULL;
    }
  
  objfile = objfile_list_ptr->objfile;
  objfile_list_ptr = objfile_list_ptr->next;

  return objfile;
}

/* APPLE LOCAL begin fix-and-continue */

static void sanity_check_symtab_obsoleted_flag (struct symtab *s)
{
  /* FIXME FIXME FIXME DO NOT RELEASE jmolenda/2003-05-01 */
  if (s != NULL && 
      SYMTAB_OBSOLETED (s) != 51 &&
      SYMTAB_OBSOLETED (s) != 50)
    error ("Symtab with invalid OBSOLETED flag setting.  Value is %d, symtab name is %s", SYMTAB_OBSOLETED (s), s->filename);
}

static void sanity_check_psymtab_obsoleted_flag (struct partial_symtab *ps)
{
  /* FIXME FIXME FIXME DO NOT RELEASE jmolenda/2003-05-01 */
  if (ps != NULL && 
      PSYMTAB_OBSOLETED (ps) != 51 &&
      PSYMTAB_OBSOLETED (ps) != 50)
    error ("Psymtab with invalid OBSOLETED flag setting.  Value is %d, psymtab name is %s", PSYMTAB_OBSOLETED (ps), ps->filename);
}

/* Return the first objfile that isn't marked as 'obsolete' (i.e. has been
   replaced by a newer version in a fix-and-continue operation.  */

struct symtab *
symtab_get_first (struct objfile *objfile, int skip_obsolete)
{
  struct symtab *s;

  s = objfile->symtabs;
  sanity_check_symtab_obsoleted_flag (s);

  while (s != NULL && skip_obsolete && SYMTAB_OBSOLETED (s) == 51)
    {
      s = s->next;
      sanity_check_symtab_obsoleted_flag (s);
    }

  return (s);
}

struct symtab *
symtab_get_next (struct symtab *s, int skip_obsolete)
{
  if (s == NULL)
    return NULL;

  s = s->next;
  sanity_check_symtab_obsoleted_flag (s);

  while (s != NULL && skip_obsolete && SYMTAB_OBSOLETED (s) == 51)
    {
      s = s->next;
      sanity_check_symtab_obsoleted_flag (s);
    }

  return s;
}

struct partial_symtab *
psymtab_get_first (struct objfile *objfile, int skip_obsolete)
{
  struct partial_symtab *ps;

  ps = objfile->psymtabs;
  sanity_check_psymtab_obsoleted_flag (ps);
  while (ps != NULL && skip_obsolete && PSYMTAB_OBSOLETED (ps) == 51)
    {
      sanity_check_psymtab_obsoleted_flag (ps);
      ps = ps->next;
    }

  return (ps);
}

struct partial_symtab *
psymtab_get_next (struct partial_symtab *ps, int skip_obsolete)
{
  if (ps == NULL)
    return NULL;

  ps = ps->next;
  sanity_check_psymtab_obsoleted_flag (ps);

  while (ps != NULL && skip_obsolete && PSYMTAB_OBSOLETED (ps) == 51)
    {
      ps = ps->next;
      sanity_check_psymtab_obsoleted_flag (ps);
    }

  return ps;
}
/* APPLE LOCAL end fix-and-continue */

void
_initialize_objfiles (void)
{
  struct cmd_list_element *c;

#if HAVE_MMAP
  c = add_set_cmd ("generate-precompiled-symfiles", class_obscure, var_boolean,
		   (char *) &mapped_symbol_files,
		   "Set if GDB should generate persistent symbol tables by default.",
		   &setlist);
  add_show_from_set (c, &showlist);

  c = add_set_cmd ("use-precompiled-symfiles", class_obscure, var_boolean,
		   (char *) &use_mapped_symbol_files,
		   "Set if GDB should use persistent symbol tables by default.",
		   &setlist);
  add_show_from_set (c, &showlist);
#endif /* HAVE_MMAP */
}