/* Read ELF (Executable and Linking Format) object files for GDB.
- Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ Free Software Foundation, Inc.
Written by Fred Fish at Cygnus Support.
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
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "bfd.h"
#include "gdb_string.h"
#include "elf-bfd.h"
+#include "elf/common.h"
+#include "elf/internal.h"
#include "elf/mips.h"
#include "symtab.h"
#include "symfile.h"
struct elfinfo
{
- file_ptr dboffset; /* Offset to dwarf debug section */
- unsigned int dbsize; /* Size of dwarf debug section */
- file_ptr lnoffset; /* Offset to dwarf line number section */
- unsigned int lnsize; /* Size of dwarf line number section */
asection *stabsect; /* Section pointer for .stab section */
asection *stabindexsect; /* Section pointer for .stab.index section */
asection *mdebugsect; /* Section pointer for .mdebug section */
static void free_elfinfo (void *);
+/* Locate the segments in ABFD. */
+
+static struct symfile_segment_data *
+elf_symfile_segments (bfd *abfd)
+{
+ Elf_Internal_Phdr *phdrs, **segments;
+ long phdrs_size;
+ int num_phdrs, num_segments, num_sections, i;
+ asection *sect;
+ struct symfile_segment_data *data;
+
+ phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);
+ if (phdrs_size == -1)
+ return NULL;
+
+ phdrs = alloca (phdrs_size);
+ num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);
+ if (num_phdrs == -1)
+ return NULL;
+
+ num_segments = 0;
+ segments = alloca (sizeof (Elf_Internal_Phdr *) * num_phdrs);
+ for (i = 0; i < num_phdrs; i++)
+ if (phdrs[i].p_type == PT_LOAD)
+ segments[num_segments++] = &phdrs[i];
+
+ if (num_segments == 0)
+ return NULL;
+
+ data = XZALLOC (struct symfile_segment_data);
+ data->num_segments = num_segments;
+ data->segment_bases = XCALLOC (num_segments, CORE_ADDR);
+ data->segment_sizes = XCALLOC (num_segments, CORE_ADDR);
+
+ for (i = 0; i < num_segments; i++)
+ {
+ data->segment_bases[i] = segments[i]->p_vaddr;
+ data->segment_sizes[i] = segments[i]->p_memsz;
+ }
+
+ num_sections = bfd_count_sections (abfd);
+ data->segment_info = XCALLOC (num_sections, int);
+
+ for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next)
+ {
+ int j;
+ CORE_ADDR vma;
+
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
+ continue;
+
+ vma = bfd_get_section_vma (abfd, sect);
+
+ for (j = 0; j < num_segments; j++)
+ if (segments[j]->p_memsz > 0
+ && vma >= segments[j]->p_vaddr
+ && (vma - segments[j]->p_vaddr) < segments[j]->p_memsz)
+ {
+ data->segment_info[i] = j + 1;
+ break;
+ }
+
+ if (bfd_get_section_size (sect) > 0 && j == num_segments)
+ warning (_("Loadable segment \"%s\" outside of ELF segments"),
+ bfd_section_name (abfd, sect));
+ }
+
+ return data;
+}
+
/* We are called once per section from elf_symfile_read. We
need to examine each section we are passed, check to see
if it is something we are interested in processing, and
struct elfinfo *ei;
ei = (struct elfinfo *) eip;
- if (strcmp (sectp->name, ".debug") == 0)
- {
- ei->dboffset = sectp->filepos;
- ei->dbsize = bfd_get_section_size (sectp);
- }
- else if (strcmp (sectp->name, ".line") == 0)
- {
- ei->lnoffset = sectp->filepos;
- ei->lnsize = bfd_get_section_size (sectp);
- }
- else if (strcmp (sectp->name, ".stab") == 0)
+ if (strcmp (sectp->name, ".stab") == 0)
{
ei->stabsect = sectp;
}
enum minimal_symbol_type ms_type,
asection *bfd_section, struct objfile *objfile)
{
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
+
if (ms_type == mst_text || ms_type == mst_file_text)
- address = SMASH_TEXT_ADDRESS (address);
+ address = gdbarch_smash_text_address (gdbarch, address);
return prim_record_minimal_symbol_and_info
- (name, address, ms_type, NULL, bfd_section->index, bfd_section, objfile);
+ (name, address, ms_type, bfd_section->index, bfd_section, objfile);
}
/*
SYNOPSIS
- void elf_symtab_read (struct objfile *objfile, int dynamic,
+ void elf_symtab_read (struct objfile *objfile, int type,
long number_of_symbols, asymbol **symbol_table)
DESCRIPTION
Given an objfile, a symbol table, and a flag indicating whether the
- symbol table contains dynamic symbols, add all the global function
- and data symbols to the minimal symbol table.
+ symbol table contains regular, dynamic, or synthetic symbols, add all
+ the global function and data symbols to the minimal symbol table.
In stabs-in-ELF, as implemented by Sun, there are some local symbols
defined in the ELF symbol table, which can be used to locate
*/
+#define ST_REGULAR 0
+#define ST_DYNAMIC 1
+#define ST_SYNTHETIC 2
+
static void
-elf_symtab_read (struct objfile *objfile, int dynamic,
+elf_symtab_read (struct objfile *objfile, int type,
long number_of_symbols, asymbol **symbol_table)
{
+ struct gdbarch *gdbarch = get_objfile_arch (objfile);
long storage_needed;
asymbol *sym;
long i;
/* If filesym is nonzero, it points to a file symbol, but we haven't
seen any section info for it yet. */
asymbol *filesym = 0;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
/* Name of filesym, as saved on the objfile_obstack. */
char *filesymname = obsavestring ("", 0, &objfile->objfile_obstack);
-#endif
struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
int stripped = (bfd_get_symcount (objfile->obfd) == 0);
continue;
}
+ /* Skip "special" symbols, e.g. ARM mapping symbols. These are
+ symbols which do not correspond to objects in the symbol table,
+ but have some other target-specific meaning. */
+ if (bfd_is_target_special_symbol (objfile->obfd, sym))
+ {
+ if (gdbarch_record_special_symbol_p (gdbarch))
+ gdbarch_record_special_symbol (gdbarch, objfile, sym);
+ continue;
+ }
+
offset = ANOFFSET (objfile->section_offsets, sym->section->index);
- if (dynamic
+ if (type == ST_DYNAMIC
&& sym->section == &bfd_und_section
&& (sym->flags & BSF_FUNCTION))
{
struct minimal_symbol *msym;
+ bfd *abfd = objfile->obfd;
+ asection *sect;
/* Symbol is a reference to a function defined in
a shared library.
symaddr = sym->value;
if (symaddr == 0)
continue;
- symaddr += offset;
+
+ /* sym->section is the undefined section. However, we want to
+ record the section where the PLT stub resides with the
+ minimal symbol. Search the section table for the one that
+ covers the stub's address. */
+ for (sect = abfd->sections; sect != NULL; sect = sect->next)
+ {
+ if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
+ continue;
+
+ if (symaddr >= bfd_get_section_vma (abfd, sect)
+ && symaddr < bfd_get_section_vma (abfd, sect)
+ + bfd_get_section_size (sect))
+ break;
+ }
+ if (!sect)
+ continue;
+
+ symaddr += ANOFFSET (objfile->section_offsets, sect->index);
+
msym = record_minimal_symbol
- ((char *) sym->name, symaddr,
- mst_solib_trampoline, sym->section, objfile);
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
+ ((char *) sym->name, symaddr, mst_solib_trampoline, sect, objfile);
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)
+ if (type == ST_DYNAMIC && !stripped)
continue;
if (sym->flags & BSF_FILE)
{
sectinfo = NULL;
}
filesym = sym;
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
filesymname =
obsavestring ((char *) filesym->name, strlen (filesym->name),
&objfile->objfile_obstack);
-#endif
}
else if (sym->flags & BSF_SECTION_SYM)
continue;
interested in will have a section. */
/* Bfd symbols are section relative. */
symaddr = sym->value + sym->section->vma;
- /* Relocate all non-absolute symbols by the section offset. */
- if (sym->section != &bfd_abs_section)
+ /* Relocate all non-absolute and non-TLS symbols by the
+ section offset. */
+ if (sym->section != &bfd_abs_section
+ && !(sym->section->flags & SEC_THREAD_LOCAL))
{
symaddr += offset;
}
{
/* This is a hack to get the minimal symbol type
right for Irix 5, which has absolute addresses
- with special section indices for dynamic symbols. */
- unsigned short shndx =
+ with special section indices for dynamic symbols.
+
+ NOTE: uweigand-20071112: Synthetic symbols do not
+ have an ELF-private part, so do not touch those. */
+ unsigned int shndx = type == ST_SYNTHETIC ? 0 :
((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
switch (shndx)
}
else if (sym->section->flags & SEC_CODE)
{
- if (sym->flags & BSF_GLOBAL)
+ if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
{
ms_type = mst_text;
}
msym = record_minimal_symbol
((char *) sym->name, symaddr,
ms_type, sym->section, objfile);
+
if (msym)
{
/* Pass symbol size field in via BFD. FIXME!!! */
- unsigned long size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
- MSYMBOL_SIZE(msym) = size;
+ elf_symbol_type *elf_sym;
+
+ /* NOTE: uweigand-20071112: A synthetic symbol does not have an
+ ELF-private part. However, in some cases (e.g. synthetic
+ 'dot' symbols on ppc64) the udata.p entry is set to point back
+ to the original ELF symbol it was derived from. Get the size
+ from that symbol. */
+ if (type != ST_SYNTHETIC)
+ elf_sym = (elf_symbol_type *) sym;
+ else
+ elf_sym = (elf_symbol_type *) sym->udata.p;
+
+ if (elf_sym)
+ MSYMBOL_SIZE(msym) = elf_sym->internal_elf_sym.st_size;
}
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
if (msym != NULL)
msym->filename = filesymname;
-#endif
- ELF_MAKE_MSYMBOL_SPECIAL (sym, msym);
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
+
+ /* For @plt symbols, also record a trampoline to the
+ destination symbol. The @plt symbol will be used in
+ disassembly, and the trampoline will be used when we are
+ trying to find the target. */
+ if (msym && ms_type == mst_text && type == ST_SYNTHETIC)
+ {
+ int len = strlen (sym->name);
+
+ if (len > 4 && strcmp (sym->name + len - 4, "@plt") == 0)
+ {
+ char *base_name = alloca (len - 4 + 1);
+ struct minimal_symbol *mtramp;
+
+ memcpy (base_name, sym->name, len - 4);
+ base_name[len - 4] = '\0';
+ mtramp = record_minimal_symbol (base_name, symaddr,
+ mst_solib_trampoline,
+ sym->section, objfile);
+ if (mtramp)
+ {
+ MSYMBOL_SIZE (mtramp) = MSYMBOL_SIZE (msym);
+ mtramp->filename = filesymname;
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, mtramp);
+ }
+ }
+ }
}
}
}
We look for sections with specific names, to tell us what debug
format to look for: FIXME!!!
- dwarf_build_psymtabs() builds psymtabs for DWARF symbols;
elfstab_build_psymtabs() handles STABS symbols;
mdebug_build_psymtabs() handles ECOFF debugging information.
error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd),
bfd_errmsg (bfd_get_error ()));
- elf_symtab_read (objfile, 0, symcount, symbol_table);
+ elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table);
}
/* Add the dynamic symbols. */
error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd),
bfd_errmsg (bfd_get_error ()));
- elf_symtab_read (objfile, 1, dynsymcount, dyn_symbol_table);
+ elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table);
}
/* Add synthetic symbols - for instance, names for any PLT entries. */
for (i = 0; i < synthcount; i++)
synth_symbol_table[i] = synthsyms + i;
make_cleanup (xfree, synth_symbol_table);
- elf_symtab_read (objfile, 0, synthcount, synth_symbol_table);
+ elf_symtab_read (objfile, ST_SYNTHETIC, synthcount, synth_symbol_table);
}
/* Install any minimal symbols that have been collected as the current
/* DWARF 2 sections */
dwarf2_build_psymtabs (objfile, mainline);
}
- else if (ei.dboffset && ei.lnoffset)
- {
- /* DWARF sections */
- dwarf_build_psymtabs (objfile,
- mainline,
- ei.dboffset, ei.dbsize,
- ei.lnoffset, ei.lnsize);
- }
/* FIXME: kettenis/20030504: This still needs to be integrated with
dwarf2read.c in a better way. */
{
xfree (objfile->deprecated_sym_stab_info);
}
+
+ dwarf2_free_objfile (objfile);
}
/* ELF specific initialization routine for reading symbols.
elf_symfile_read, /* sym_read: read a symbol file into symtab */
elf_symfile_finish, /* sym_finish: finished with file, cleanup */
default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */
+ elf_symfile_segments, /* sym_segments: Get segment information from
+ a file. */
+ NULL, /* sym_read_linetable */
NULL /* next: pointer to next struct sym_fns */
};