/* 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, 2006, 2007, 2008
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
Written by Fred Fish at Cygnus Support.
#include "gdb-stabs.h"
#include "complaints.h"
#include "demangle.h"
+#include "psympriv.h"
extern void _initialize_elfread (void);
+/* Forward declaration. */
+static const struct sym_fns elf_sym_fns_gdb_index;
+
/* The struct elfinfo is available only during ELF symbol table and
psymtab reading. It is destroyed at the completion of psymtab-reading.
It's local to elf_symfile_read. */
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)
+ && (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)
+ /* We should have found a segment for every non-empty section.
+ If we haven't, we will not relocate this section by any
+ offsets we apply to the segments. As an exception, do not
+ warn about SHT_NOBITS sections; in normal ELF execution
+ environments, SHT_NOBITS means zero-initialized and belongs
+ in a segment, but in no-OS environments some tools (e.g. ARM
+ RealView) use SHT_NOBITS for uninitialized data. Since it is
+ uninitialized, it doesn't need a program header. Such
+ binaries are not relocatable. */
+ if (bfd_get_section_size (sect) > 0 && j == num_segments
+ && (bfd_get_section_flags (abfd, sect) & SEC_LOAD) != 0)
warning (_("Loadable segment \"%s\" outside of ELF segments"),
bfd_section_name (abfd, sect));
}
FIXME: The section names should not be hardwired strings (what
should they be? I don't think most object file formats have enough
- section flags to specify what kind of debug section it is
+ section flags to specify what kind of debug section it is.
-kingdon). */
static void
}
static struct minimal_symbol *
-record_minimal_symbol (char *name, CORE_ADDR address,
+record_minimal_symbol (const char *name, int name_len, int copy_name,
+ CORE_ADDR address,
enum minimal_symbol_type ms_type,
asection *bfd_section, struct objfile *objfile)
{
if (ms_type == mst_text || ms_type == mst_file_text)
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);
+ return prim_record_minimal_symbol_full (name, name_len, copy_name, address,
+ ms_type, bfd_section->index,
+ bfd_section, objfile);
}
/*
static void
elf_symtab_read (struct objfile *objfile, int type,
- long number_of_symbols, asymbol **symbol_table)
+ long number_of_symbols, asymbol **symbol_table,
+ int copy_names)
{
struct gdbarch *gdbarch = get_objfile_arch (objfile);
- long storage_needed;
asymbol *sym;
long i;
CORE_ADDR symaddr;
/* If filesym is nonzero, it points to a file symbol, but we haven't
seen any section info for it yet. */
asymbol *filesym = 0;
- /* Name of filesym, as saved on the objfile_obstack. */
- char *filesymname = obsavestring ("", 0, &objfile->objfile_obstack);
+ /* Name of filesym. This is either a constant string or is saved on
+ the objfile's obstack. */
+ char *filesymname = "";
struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
int stripped = (bfd_get_symcount (objfile->obfd) == 0);
if (sym->name == NULL || *sym->name == '\0')
{
/* Skip names that don't exist (shouldn't happen), or names
- that are null strings (may happen). */
+ that are null strings (may happen). */
continue;
}
of the corresponding entry in the procedure linkage table,
plus the desired section offset.
If its value is zero then the dynamic linker has to resolve
- the symbol. We are unable to find any meaningful address
+ 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)
symaddr += ANOFFSET (objfile->section_offsets, sect->index);
msym = record_minimal_symbol
- ((char *) sym->name, symaddr, mst_solib_trampoline, sect, objfile);
+ (sym->name, strlen (sym->name), copy_names,
+ symaddr, mst_solib_trampoline, sect, objfile);
if (msym != NULL)
msym->filename = filesymname;
continue;
/* 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. */
- /* Bfd symbols are section relative. */
+ 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;
}
/* For non-absolute symbols, use the type of the section
they are relative to, to intuit text/data. Bfd provides
- no way of figuring this out for absolute symbols. */
+ no way of figuring this out for absolute symbols. */
if (sym->section == &bfd_abs_section)
{
/* This is a hack to get the minimal symbol type
}
/* If it is an Irix dynamic symbol, skip section name
- symbols, relocate all others by section offset. */
+ symbols, relocate all others by section offset. */
if (ms_type != mst_abs)
{
if (sym->name[0] == '.')
/* Named Local variable in a Data section.
Check its name for stabs-in-elf. */
int special_local_sect;
+
if (strcmp ("Bbss.bss", sym->name) == 0)
special_local_sect = SECT_OFF_BSS (objfile);
else if (strcmp ("Ddata.data", sym->name) == 0)
int max_index;
size_t size;
- max_index
- = max (SECT_OFF_BSS (objfile),
- max (SECT_OFF_DATA (objfile),
- SECT_OFF_RODATA (objfile)));
+ max_index = SECT_OFF_BSS (objfile);
+ if (objfile->sect_index_data > max_index)
+ max_index = objfile->sect_index_data;
+ if (objfile->sect_index_rodata > max_index)
+ max_index = objfile->sect_index_rodata;
/* max_index is the largest index we'll
use into this array, so we must
if (filesym == NULL)
{
complaint (&symfile_complaints,
- _("elf/stab section information %s without a preceding file symbol"),
+ _("elf/stab section information %s "
+ "without a preceding file symbol"),
sym->name);
}
else
}
if (sectinfo->sections[special_local_sect] != 0)
complaint (&symfile_complaints,
- _("duplicated elf/stab section information for %s"),
+ _("duplicated elf/stab section "
+ "information for %s"),
sectinfo->filename);
/* BFD symbols are section relative. */
symaddr = sym->value + sym->section->vma;
hob with actions like finding what function the PC
is in. Ignore them if they aren't text, data, or bss. */
/* ms_type = mst_unknown; */
- continue; /* Skip this symbol. */
+ continue; /* Skip this symbol. */
}
msym = record_minimal_symbol
- ((char *) sym->name, symaddr,
+ (sym->name, strlen (sym->name), copy_names, symaddr,
ms_type, sym->section, objfile);
if (msym)
if (elf_sym)
MSYMBOL_SIZE(msym) = elf_sym->internal_elf_sym.st_size;
+
+ msym->filename = filesymname;
+ gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
}
- if (msym != NULL)
- msym->filename = filesymname;
- 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
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,
+ mtramp = record_minimal_symbol (sym->name, len - 4, 1,
+ symaddr,
mst_solib_trampoline,
sym->section, objfile);
if (mtramp)
}
}
+struct build_id
+ {
+ size_t size;
+ gdb_byte data[1];
+ };
+
+/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
+
+static struct build_id *
+build_id_bfd_get (bfd *abfd)
+{
+ struct build_id *retval;
+
+ if (!bfd_check_format (abfd, bfd_object)
+ || bfd_get_flavour (abfd) != bfd_target_elf_flavour
+ || elf_tdata (abfd)->build_id == NULL)
+ return NULL;
+
+ retval = xmalloc (sizeof *retval - 1 + elf_tdata (abfd)->build_id_size);
+ retval->size = elf_tdata (abfd)->build_id_size;
+ memcpy (retval->data, elf_tdata (abfd)->build_id, retval->size);
+
+ return retval;
+}
+
+/* Return if FILENAME has NT_GNU_BUILD_ID matching the CHECK value. */
+
+static int
+build_id_verify (const char *filename, struct build_id *check)
+{
+ bfd *abfd;
+ struct build_id *found = NULL;
+ int retval = 0;
+
+ /* We expect to be silent on the non-existing files. */
+ abfd = bfd_open_maybe_remote (filename);
+ if (abfd == NULL)
+ return 0;
+
+ found = build_id_bfd_get (abfd);
+
+ if (found == NULL)
+ warning (_("File \"%s\" has no build-id, file skipped"), filename);
+ else if (found->size != check->size
+ || memcmp (found->data, check->data, found->size) != 0)
+ warning (_("File \"%s\" has a different build-id, file skipped"),
+ filename);
+ else
+ retval = 1;
+
+ gdb_bfd_close_or_warn (abfd);
+
+ xfree (found);
+
+ return retval;
+}
+
+static char *
+build_id_to_debug_filename (struct build_id *build_id)
+{
+ char *link, *debugdir, *retval = NULL;
+
+ /* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
+ link = alloca (strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1
+ + 2 * build_id->size + (sizeof ".debug" - 1) + 1);
+
+ /* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
+ cause "/.build-id/..." lookups. */
+
+ debugdir = debug_file_directory;
+ do
+ {
+ char *s, *debugdir_end;
+ gdb_byte *data = build_id->data;
+ size_t size = build_id->size;
+
+ while (*debugdir == DIRNAME_SEPARATOR)
+ debugdir++;
+
+ debugdir_end = strchr (debugdir, DIRNAME_SEPARATOR);
+ if (debugdir_end == NULL)
+ debugdir_end = &debugdir[strlen (debugdir)];
+
+ memcpy (link, debugdir, debugdir_end - debugdir);
+ s = &link[debugdir_end - debugdir];
+ s += sprintf (s, "/.build-id/");
+ if (size > 0)
+ {
+ size--;
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ }
+ if (size > 0)
+ *s++ = '/';
+ while (size-- > 0)
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ strcpy (s, ".debug");
+
+ /* lrealpath() is expensive even for the usually non-existent files. */
+ if (access (link, F_OK) == 0)
+ retval = lrealpath (link);
+
+ if (retval != NULL && !build_id_verify (retval, build_id))
+ {
+ xfree (retval);
+ retval = NULL;
+ }
+
+ if (retval != NULL)
+ break;
+
+ debugdir = debugdir_end;
+ }
+ while (*debugdir != 0);
+
+ return retval;
+}
+
+static char *
+find_separate_debug_file_by_buildid (struct objfile *objfile)
+{
+ struct build_id *build_id;
+
+ build_id = build_id_bfd_get (objfile->obfd);
+ if (build_id != NULL)
+ {
+ char *build_id_name;
+
+ build_id_name = build_id_to_debug_filename (build_id);
+ xfree (build_id);
+ /* Prevent looping on a stripped .debug file. */
+ if (build_id_name != NULL && strcmp (build_id_name, objfile->name) == 0)
+ {
+ warning (_("\"%s\": separate debug info file has no debug info"),
+ build_id_name);
+ xfree (build_id_name);
+ }
+ else if (build_id_name != NULL)
+ return build_id_name;
+ }
+ return NULL;
+}
+
/* Scan and build partial symbols for a symbol file.
We have been initialized by a call to elf_symfile_init, which
currently does nothing.
in each section. We simplify it down to a single offset for all
symbols. FIXME.
- MAINLINE is true if we are reading the main symbol
- table (as opposed to a shared lib or dynamically loaded file).
-
This function only does the minimum work necessary for letting the
user "name" things symbolically; it does not read the entire symtab.
Instead, it reads the external and static symbols and puts them in partial
capability even for files compiled without -g. */
static void
-elf_symfile_read (struct objfile *objfile, int mainline)
+elf_symfile_read (struct objfile *objfile, int symfile_flags)
{
bfd *abfd = objfile->obfd;
struct elfinfo ei;
struct cleanup *back_to;
- CORE_ADDR offset;
long symcount = 0, dynsymcount = 0, synthcount, storage_needed;
asymbol **symbol_table = NULL, **dyn_symbol_table = NULL;
asymbol *synthsyms;
memset ((char *) &ei, 0, sizeof (ei));
- /* Allocate struct to keep track of the symfile */
+ /* Allocate struct to keep track of the symfile. */
objfile->deprecated_sym_stab_info = (struct dbx_symfile_info *)
xmalloc (sizeof (struct dbx_symfile_info));
- memset ((char *) objfile->deprecated_sym_stab_info, 0, sizeof (struct dbx_symfile_info));
+ memset ((char *) objfile->deprecated_sym_stab_info,
+ 0, sizeof (struct dbx_symfile_info));
make_cleanup (free_elfinfo, (void *) objfile);
- /* Process the normal ELF symbol table first. This may write some
- chain of info into the dbx_symfile_info in objfile->deprecated_sym_stab_info,
- which can later be used by elfstab_offset_sections. */
+ /* Process the normal ELF symbol table first. This may write some
+ chain of info into the dbx_symfile_info in
+ objfile->deprecated_sym_stab_info, which can later be used by
+ elfstab_offset_sections. */
storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
if (storage_needed < 0)
- error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd),
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
bfd_errmsg (bfd_get_error ()));
if (storage_needed > 0)
symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
if (symcount < 0)
- error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd),
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
bfd_errmsg (bfd_get_error ()));
- elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table);
+ elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table, 0);
}
/* Add the dynamic symbols. */
if (storage_needed > 0)
{
- dyn_symbol_table = (asymbol **) xmalloc (storage_needed);
- make_cleanup (xfree, dyn_symbol_table);
+ /* Memory gets permanently referenced from ABFD after
+ bfd_get_synthetic_symtab so it must not get freed before ABFD gets.
+ It happens only in the case when elf_slurp_reloc_table sees
+ asection->relocation NULL. Determining which section is asection is
+ done by _bfd_elf_get_synthetic_symtab which is all a bfd
+ implementation detail, though. */
+
+ dyn_symbol_table = bfd_alloc (abfd, storage_needed);
dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd,
dyn_symbol_table);
if (dynsymcount < 0)
- error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd),
+ error (_("Can't read symbols from %s: %s"),
+ bfd_get_filename (objfile->obfd),
bfd_errmsg (bfd_get_error ()));
- elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table);
+ elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table, 0);
}
/* 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, ST_SYNTHETIC, synthcount, synth_symbol_table);
+ elf_symtab_read (objfile, ST_SYNTHETIC, synthcount,
+ synth_symbol_table, 1);
}
/* Install any minimal symbols that have been collected as the current
do_cleanups (back_to);
/* Now process debugging information, which is contained in
- special ELF sections. */
+ special ELF sections. */
- /* 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)
- {
- init_psymbol_list (objfile, 0);
- mainline = 0;
- }
-
- /* We first have to find them... */
+ /* We first have to find them... */
bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
/* ELF debugging information is inserted into the psymtab in the
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. */
+ an included file XCOFF info is useless. */
if (ei.mdebugsect)
{
/* FIXME should probably warn about a stab section without a stabstr. */
if (str_sect)
elfstab_build_psymtabs (objfile,
- mainline,
ei.stabsect,
str_sect->filepos,
bfd_section_size (abfd, str_sect));
}
- if (dwarf2_has_info (objfile))
+
+ if (dwarf2_has_info (objfile) && dwarf2_initialize_objfile (objfile))
+ objfile->sf = &elf_sym_fns_gdb_index;
+
+ /* If the file has its own symbol tables it has no separate debug
+ info. `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
+ SYMTABS/PSYMTABS. `.gnu_debuglink' may no longer be present with
+ `.note.gnu.build-id'. */
+ if (!objfile_has_partial_symbols (objfile))
{
- /* DWARF 2 sections */
- dwarf2_build_psymtabs (objfile, mainline);
- }
+ char *debugfile;
+
+ debugfile = find_separate_debug_file_by_buildid (objfile);
+
+ if (debugfile == NULL)
+ debugfile = find_separate_debug_file_by_debuglink (objfile);
- /* FIXME: kettenis/20030504: This still needs to be integrated with
- dwarf2read.c in a better way. */
- dwarf2_build_frame_info (objfile);
+ if (debugfile)
+ {
+ bfd *abfd = symfile_bfd_open (debugfile);
+
+ symbol_file_add_separate (abfd, symfile_flags, objfile);
+ xfree (debugfile);
+ }
+ }
}
/* This cleans up the objfile's deprecated_sym_stab_info pointer, and
file is specified (not just adding some symbols from another file, e.g. a
shared library).
- We reinitialize buildsym, since we may be reading stabs from an ELF file. */
+ We reinitialize buildsym, since we may be reading stabs from an ELF
+ file. */
static void
elf_new_init (struct objfile *ignore)
/* Perform any local cleanups required when we are done with a particular
objfile. I.E, we are in the process of discarding all symbol information
for an objfile, freeing up all memory held for it, and unlinking the
- objfile struct from the global list of known objfiles. */
+ objfile struct from the global list of known objfiles. */
static void
elf_symfile_finish (struct objfile *objfile)
a pointer to "private data" which we can fill with goodies.
For now at least, we have nothing in particular to do, so this function is
- just a stub. */
+ just a stub. */
static void
elf_symfile_init (struct objfile *objfile)
void
elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
{
- char *filename = pst->filename;
+ const char *filename = pst->filename;
struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info;
struct stab_section_info *maybe = dbx->stab_section_info;
struct stab_section_info *questionable = 0;
/* FIXME: This linear search could speed up significantly
if it was chained in the right order to match how we search it,
- and if we unchained when we found a match. */
+ and if we unchained when we found a match. */
for (; maybe; maybe = maybe->next)
{
if (filename[0] == maybe->filename[0]
if (maybe == 0 && questionable != 0)
{
complaint (&symfile_complaints,
- _("elf/stab section information questionable for %s"), filename);
+ _("elf/stab section information questionable for %s"),
+ filename);
maybe = questionable;
}
\f
/* Register that we are able to handle ELF object file formats. */
-static struct sym_fns elf_sym_fns =
+static const struct sym_fns elf_sym_fns =
+{
+ bfd_target_elf_flavour,
+ elf_new_init, /* init anything gbl to entire symtab */
+ elf_symfile_init, /* read initial info, setup for sym_read() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocation */
+ elf_symfile_segments, /* Get segment information from a file. */
+ NULL,
+ default_symfile_relocate, /* Relocate a debug section. */
+ &psym_functions
+};
+
+/* The same as elf_sym_fns, but not registered and uses the
+ DWARF-specific GNU index rather than psymtab. */
+static const struct sym_fns elf_sym_fns_gdb_index =
{
bfd_target_elf_flavour,
- elf_new_init, /* sym_new_init: init anything gbl to entire symtab */
- 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 */
- 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 */
+ elf_new_init, /* init anything gbl to entire symab */
+ elf_symfile_init, /* read initial info, setup for sym_red() */
+ elf_symfile_read, /* read a symbol file into symtab */
+ elf_symfile_finish, /* finished with file, cleanup */
+ default_symfile_offsets, /* Translate ext. to int. relocatin */
+ elf_symfile_segments, /* Get segment information from a file. */
+ NULL,
+ default_symfile_relocate, /* Relocate a debug section. */
+ &dwarf2_gdb_index_functions
};
void
projects / deliverable / binutils-gdb.git / blobdiff