/* Read ELF (Executable and Linking Format) object files for GDB.
- Copyright 1991, 1992 Free Software Foundation, Inc.
+ Copyright 1991, 1992, 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
Written by Fred Fish at Cygnus Support.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "bfd.h"
-#include <time.h> /* For time_t in libbfd.h. */
-#include <sys/types.h> /* For time_t, if not in time.h. */
-#include "libbfd.h" /* For bfd_elf_find_section */
-#include "libelf.h"
+#include "gdb_string.h"
+#include "elf-bfd.h"
+#include "elf/mips.h"
#include "symtab.h"
#include "symfile.h"
#include "objfiles.h"
#include "stabsread.h"
#include "gdb-stabs.h"
#include "complaints.h"
-#include <string.h>
#include "demangle.h"
/* The struct elfinfo is available only during ELF symbol table and
elf_symfile_finish PARAMS ((struct objfile *));
static void
-elf_symtab_read PARAMS ((bfd *, CORE_ADDR, struct objfile *));
+elf_symtab_read PARAMS ((bfd *, CORE_ADDR, struct objfile *, int));
static void
free_elfinfo PARAMS ((void *));
-static struct section_offsets *
-elf_symfile_offsets PARAMS ((struct objfile *, CORE_ADDR));
-
-static void
+static struct minimal_symbol *
record_minimal_symbol_and_info PARAMS ((char *, CORE_ADDR,
enum minimal_symbol_type, char *,
+ asection *bfd_section,
struct objfile *));
static void
#endif
-static void
-record_minimal_symbol_and_info (name, address, ms_type, info, objfile)
+static struct minimal_symbol *
+record_minimal_symbol_and_info (name, address, ms_type, info, bfd_section,
+ objfile)
char *name;
CORE_ADDR address;
enum minimal_symbol_type ms_type;
char *info; /* FIXME, is this really char *? */
+ asection *bfd_section;
struct objfile *objfile;
{
int section;
break;
}
- name = obsavestring (name, strlen (name), &objfile -> symbol_obstack);
- prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
- objfile);
+ return prim_record_minimal_symbol_and_info
+ (name, address, ms_type, info, section, bfd_section, objfile);
}
/*
SYNOPSIS
void elf_symtab_read (bfd *abfd, CORE_ADDR addr,
- struct objfile *objfile)
+ struct objfile *objfile, int dynamic)
DESCRIPTION
*/
static void
-elf_symtab_read (abfd, addr, objfile)
+elf_symtab_read (abfd, addr, objfile, dynamic)
bfd *abfd;
CORE_ADDR addr;
struct objfile *objfile;
+ int dynamic;
{
long storage_needed;
asymbol *sym;
/* If filesym is nonzero, it points to a file symbol, but we haven't
seen any section info for it yet. */
asymbol *filesym = 0;
- struct dbx_symfile_info *dbx = (struct dbx_symfile_info *)
- objfile->sym_stab_info;
+#ifdef SOFUN_ADDRESS_MAYBE_MISSING
+ /* Name of filesym, as saved on the symbol_obstack. */
+ char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack);
+#endif
+ struct dbx_symfile_info *dbx = objfile->sym_stab_info;
unsigned long size;
-
- storage_needed = bfd_get_symtab_upper_bound (abfd);
- if (storage_needed < 0)
- error ("Can't read symbols from %s: %s", bfd_get_filename (abfd),
- bfd_errmsg (bfd_get_error ()));
+ int stripped = (bfd_get_symcount (abfd) == 0);
+
+ if (dynamic)
+ {
+ storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd);
+
+ /* Nothing to be done if there is no dynamic symtab. */
+ if (storage_needed < 0)
+ return;
+ }
+ else
+ {
+ storage_needed = bfd_get_symtab_upper_bound (abfd);
+ if (storage_needed < 0)
+ error ("Can't read symbols from %s: %s", bfd_get_filename (abfd),
+ bfd_errmsg (bfd_get_error ()));
+ }
if (storage_needed > 0)
{
symbol_table = (asymbol **) xmalloc (storage_needed);
back_to = make_cleanup (free, symbol_table);
- number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table);
+ if (dynamic)
+ number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd,
+ symbol_table);
+ else
+ number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table);
if (number_of_symbols < 0)
error ("Can't read symbols from %s: %s", bfd_get_filename (abfd),
bfd_errmsg (bfd_get_error ()));
that are null strings (may happen). */
continue;
}
+
+ if (dynamic
+ && sym -> section == &bfd_und_section
+ && (sym -> flags & BSF_FUNCTION))
+ {
+ struct minimal_symbol *msym;
+
+ /* Symbol is a reference to a function defined in
+ a shared library.
+ If its value is non zero then it is usually the address
+ of the corresponding entry in the procedure linkage table,
+ relative to the base address.
+ If its value is zero then the dynamic linker has to resolve
+ the symbol. We are unable to find any meaningful address
+ for this symbol in the executable file, so we skip it. */
+ symaddr = sym -> value;
+ if (symaddr == 0)
+ continue;
+ symaddr += addr;
+ msym = record_minimal_symbol_and_info
+ ((char *) sym -> name, symaddr,
+ mst_solib_trampoline, NULL, sym -> section, objfile);
+#ifdef SOFUN_ADDRESS_MAYBE_MISSING
+ if (msym != NULL)
+ msym->filename = filesymname;
+#endif
+ continue;
+ }
+
+ /* If it is a nonstripped executable, do not enter dynamic
+ symbols, as the dynamic symbol table is usually a subset
+ of the main symbol table. */
+ if (dynamic && !stripped)
+ continue;
if (sym -> flags & BSF_FILE)
{
/* STT_FILE debugging symbol that helps stabs-in-elf debugging.
sectinfo = NULL;
}
filesym = sym;
+#ifdef SOFUN_ADDRESS_MAYBE_MISSING
+ filesymname =
+ obsavestring ((char *)filesym->name, strlen (filesym->name),
+ &objfile->symbol_obstack);
+#endif
}
else if (sym -> flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
{
+ struct minimal_symbol *msym;
+
/* Select global/local/weak symbols. Note that bfd puts abs
symbols in their own section, so all symbols we are
interested in will have a section. */
no way of figuring this out for absolute symbols. */
if (sym -> section == &bfd_abs_section)
{
- ms_type = mst_abs;
+ /* This is a hack to get the minimal symbol type
+ right for Irix 5, which has absolute adresses
+ with special section indices for dynamic symbols. */
+ unsigned short shndx =
+ ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
+
+ switch (shndx)
+ {
+ case SHN_MIPS_TEXT:
+ ms_type = mst_text;
+ break;
+ case SHN_MIPS_DATA:
+ ms_type = mst_data;
+ break;
+ case SHN_MIPS_ACOMMON:
+ ms_type = mst_bss;
+ break;
+ default:
+ ms_type = mst_abs;
+ }
+
+ /* If it is an Irix dynamic symbol, skip section name
+ symbols, relocate all others. */
+ if (ms_type != mst_abs)
+ {
+ if (sym->name[0] == '.')
+ continue;
+ symaddr += addr;
+ }
}
else if (sym -> section -> flags & SEC_CODE)
{
{
ms_type = mst_text;
}
- else if (sym->name[0] == '.' && sym->name[1] == 'L')
+ else if ((sym->name[0] == '.' && sym->name[1] == 'L')
+ || ((sym -> flags & BSF_LOCAL)
+ && sym->name[0] == '$'
+ && sym->name[1] == 'L'))
/* Looks like a compiler-generated label. Skip it.
The assembler should be skipping these (to keep
executables small), but apparently with gcc on the
should be harmless (but I encourage people to fix this
in the assembler instead of adding checks here). */
continue;
+#ifdef HARRIS_TARGET
+ else if (sym->name[0] == '.' && sym->name[1] == '.')
+ {
+ /* Looks like a Harris compiler generated label for the
+ purpose of marking instructions that are relevant to
+ DWARF dies. The assembler can't get rid of these
+ because they are relocatable addresses that the
+ linker needs to resolve. */
+ continue;
+ }
+#endif
else
{
ms_type = mst_file_text;
}
/* Pass symbol size field in via BFD. FIXME!!! */
size = ((elf_symbol_type *) sym) -> internal_elf_sym.st_size;
- record_minimal_symbol_and_info ((char *) sym -> name, symaddr,
- ms_type, (PTR) size, objfile);
+ msym = record_minimal_symbol_and_info
+ ((char *) sym -> name, symaddr,
+ ms_type, (PTR) size, sym -> section, objfile);
+#ifdef SOFUN_ADDRESS_MAYBE_MISSING
+ if (msym != NULL)
+ msym->filename = filesymname;
+#endif
+#ifdef MAKE_MSYMBOL_SPECIAL
+ MAKE_MSYMBOL_SPECIAL (sym,msym);
+#endif
}
}
do_cleanups (back_to);
memset ((char *) &ei, 0, sizeof (ei));
/* Allocate struct to keep track of the symfile */
- objfile->sym_stab_info = (PTR)
+ objfile->sym_stab_info = (struct dbx_symfile_info *)
xmmalloc (objfile -> md, sizeof (struct dbx_symfile_info));
memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info));
make_cleanup (free_elfinfo, (PTR) objfile);
/* FIXME, should take a section_offsets param, not just an offset. */
offset = ANOFFSET (section_offsets, 0);
- elf_symtab_read (abfd, offset, objfile);
+ elf_symtab_read (abfd, offset, objfile, 0);
+
+ /* Add the dynamic symbols. */
+
+ elf_symtab_read (abfd, offset, objfile, 1);
/* Now process debugging information, which is contained in
- special ELF sections. We first have to find them... */
+ special ELF sections. */
- bfd_map_over_sections (abfd, elf_locate_sections, (PTR) &ei);
- if (ei.dboffset && ei.lnoffset)
+ /* If we are reinitializing, or if we have never loaded syms yet,
+ set table to empty. MAINLINE is cleared so that *_read_psymtab
+ functions do not all also re-initialize the psymbol table. */
+ if (mainline)
{
- /* DWARF sections */
- dwarf_build_psymtabs (objfile,
- section_offsets, mainline,
- ei.dboffset, ei.dbsize,
- ei.lnoffset, ei.lnsize);
- }
- if (ei.stabsect)
- {
- /* STABS sections */
-
- /* FIXME: Sun didn't really know how to implement this well.
- They made .stab sections that don't point to the .stabstr
- section with the sh_link field. BFD doesn't make string table
- sections visible to the caller. So we have to search the
- ELF section table, not the BFD section table, for the string
- table. */
- struct elf32_internal_shdr *elf_sect;
-
- elf_sect = bfd_elf_find_section (abfd, ".stabstr");
- if (elf_sect)
- elfstab_build_psymtabs (objfile,
- section_offsets,
- mainline,
- ei.stabsect->filepos, /* .stab offset */
- bfd_get_section_size_before_reloc (ei.stabsect),/* .stab size */
- (file_ptr) elf_sect->sh_offset, /* .stabstr offset */
- elf_sect->sh_size); /* .stabstr size */
+ init_psymbol_list (objfile, 0);
+ mainline = 0;
}
+
+ /* We first have to find them... */
+ bfd_map_over_sections (abfd, elf_locate_sections, (PTR) &ei);
+
+ /* ELF debugging information is inserted into the psymtab in the
+ order of least informative first - most informative last. Since
+ the psymtab table is searched `most recent insertion first' this
+ increases the probability that more detailed debug information
+ for a section is found.
+
+ For instance, an object file might contain both .mdebug (XCOFF)
+ and .debug_info (DWARF2) sections then .mdebug is inserted first
+ (searched last) and DWARF2 is inserted last (searched first). If
+ we don't do this then the XCOFF info is found first - for code in
+ an included file XCOFF info is useless. */
+
if (ei.mdebugsect)
{
const struct ecoff_debug_swap *swap;
elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect,
section_offsets);
}
+ if (ei.stabsect)
+ {
+ asection *str_sect;
+
+ /* Stab sections have an associated string table that looks like
+ a separate section. */
+ str_sect = bfd_get_section_by_name (abfd, ".stabstr");
- if (!have_partial_symbols ())
+ /* FIXME should probably warn about a stab section without a stabstr. */
+ if (str_sect)
+ elfstab_build_psymtabs (objfile,
+ section_offsets,
+ mainline,
+ ei.stabsect->filepos,
+ bfd_section_size (abfd, ei.stabsect),
+ str_sect->filepos,
+ bfd_section_size (abfd, str_sect));
+ }
+ if (dwarf2_has_info (abfd))
+ {
+ /* DWARF 2 sections */
+ dwarf2_build_psymtabs (objfile, section_offsets, mainline);
+ }
+ else if (ei.dboffset && ei.lnoffset)
{
- wrap_here ("");
- printf_filtered ("(no debugging symbols found)...");
- wrap_here ("");
+ /* DWARF sections */
+ dwarf_build_psymtabs (objfile,
+ section_offsets, mainline,
+ ei.dboffset, ei.dbsize,
+ ei.lnoffset, ei.lnsize);
}
/* Install any minimal symbols that have been collected as the current
PTR objp;
{
struct objfile *objfile = (struct objfile *)objp;
- struct dbx_symfile_info *dbxinfo = (struct dbx_symfile_info *)
- objfile->sym_stab_info;
+ struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info;
struct stab_section_info *ssi, *nssi;
ssi = dbxinfo->stab_section_info;
just a stub. */
static void
-elf_symfile_init (ignore)
- struct objfile *ignore;
-{
-}
-
-/* ELF specific parsing routine for section offsets.
-
- Plain and simple for now. */
-
-static
-struct section_offsets *
-elf_symfile_offsets (objfile, addr)
+elf_symfile_init (objfile)
struct objfile *objfile;
- CORE_ADDR addr;
{
- struct section_offsets *section_offsets;
- int i;
-
- objfile->num_sections = SECT_OFF_MAX;
- section_offsets = (struct section_offsets *)
- obstack_alloc (&objfile -> psymbol_obstack,
- sizeof (struct section_offsets)
- + sizeof (section_offsets->offsets) * (SECT_OFF_MAX-1));
-
- for (i = 0; i < SECT_OFF_MAX; i++)
- ANOFFSET (section_offsets, i) = addr;
-
- return section_offsets;
+ /* ELF objects may be reordered, so set OBJF_REORDERED. If we
+ find this causes a significant slowdown in gdb then we could
+ set it in the debug symbol readers only when necessary. */
+ objfile->flags |= OBJF_REORDERED;
}
-\f
+
/* When handling an ELF file that contains Sun STABS debug info,
some of the debug info is relative to the particular chunk of the
section that was generated in its individual .o file. E.g.
struct partial_symtab *pst;
{
char *filename = pst->filename;
- struct dbx_symfile_info *dbx = (struct dbx_symfile_info *)
- objfile->sym_stab_info;
+ struct dbx_symfile_info *dbx = objfile->sym_stab_info;
struct stab_section_info *maybe = dbx->stab_section_info;
struct stab_section_info *questionable = 0;
int i;
elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */
elf_symfile_read, /* sym_read: read a symbol file into symtab */
elf_symfile_finish, /* sym_finish: finished with file, cleanup */
- elf_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */
+ default_symfile_offsets,
+ /* sym_offsets: Translate ext. to int. relocation */
NULL /* next: pointer to next struct sym_fns */
};