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Diffstat (limited to 'gdb/machoread.c')
| -rw-r--r-- | gdb/machoread.c | 694 |
1 files changed, 694 insertions, 0 deletions
diff --git a/gdb/machoread.c b/gdb/machoread.c new file mode 100644 index 0000000..f15495f --- /dev/null +++ b/gdb/machoread.c @@ -0,0 +1,694 @@ +/* Darwin support for GDB, the GNU debugger. + Copyright (C) 2008 Free Software Foundation, Inc. + + Contributed by AdaCore. + + 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 3 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, see <http://www.gnu.org/licenses/>. + */ + +#include "defs.h" +#include "symtab.h" +#include "gdbtypes.h" +#include "bfd.h" +#include "symfile.h" +#include "objfiles.h" +#include "buildsym.h" +#include "gdbcmd.h" +#include "gdbcore.h" +#include "mach-o.h" +#include "gdb_assert.h" +#include "aout/stab_gnu.h" +#include "vec.h" + +#include <string.h> + +/* If non-zero displays debugging message. */ +static int mach_o_debug_level = 0; + +static void +macho_new_init (struct objfile *objfile) +{ +} + +static void +macho_symfile_init (struct objfile *objfile) +{ + objfile->flags |= OBJF_REORDERED; + init_entry_point_info (objfile); +} + +/* Dwarf debugging information are never in the final executable. They stay + in object files and the executable contains the list of object files read + during the link. + Each time an oso (other source) is found in the executable, the reader + creates such a structure. They are read after the processing of the + executable. +*/ +typedef struct oso_el +{ + /* Object file name. */ + const char *name; + + /* Associated time stamp. */ + unsigned long mtime; + + /* Number of sections. This is the length of SYMBOLS and OFFSETS array. */ + int num_sections; + + /* Each seaction of the object file is represented by a symbol and its + offset. */ + asymbol **symbols; + bfd_vma *offsets; +} +oso_el; + +/* Vector of object files to be read after the executable. */ +DEF_VEC_O (oso_el); +static VEC (oso_el) *oso_vector; + +/* Add a new OSO to the vector. */ +static void +macho_add_oso (const asymbol *oso_sym, int nbr_sections, + asymbol **symbols, bfd_vma *offsets) +{ + oso_el el; + + el.name = oso_sym->name; + el.mtime = oso_sym->value; + el.num_sections = nbr_sections; + el.symbols = symbols; + el.offsets = offsets; + VEC_safe_push (oso_el, oso_vector, &el); +} + +/* Build the minimal symbol table from SYMBOL_TABLE of length + NUMBER_OF_SYMBOLS for OBJFILE. + Read OSO files at the end. */ +static void +macho_symtab_read (struct objfile *objfile, + long number_of_symbols, asymbol **symbol_table) +{ + struct gdbarch *gdbarch = get_objfile_arch (objfile); + long storage_needed; + asymbol *sym; + long i, j; + CORE_ADDR offset; + enum minimal_symbol_type ms_type; + unsigned int nbr_sections = bfd_count_sections (objfile->obfd); + asymbol **first_symbol = NULL; + bfd_vma *first_offset = NULL; + const asymbol *oso_file = NULL; + + for (i = 0; i < number_of_symbols; i++) + { + sym = symbol_table[i]; + offset = ANOFFSET (objfile->section_offsets, sym->section->index); + + if (sym->flags & BSF_DEBUGGING) + { + unsigned char type = BFD_MACH_O_SYM_NTYPE(sym); + bfd_vma addr; + + switch (type) + { + case N_SO: + if ((sym->name == NULL || sym->name[0] == 0) + && oso_file != NULL) + { + macho_add_oso (oso_file, nbr_sections, + first_symbol, first_offset); + first_symbol = NULL; + first_offset = NULL; + oso_file = NULL; + } + break; + case N_FUN: + case N_STSYM: + if (sym->name == NULL || sym->name[0] == '\0') + break; + /* Fall through. */ + case N_BNSYM: + gdb_assert (oso_file != NULL); + addr = sym->value + + bfd_get_section_vma (sym->section->bfd, sym->section); + if (addr != 0 + && first_symbol[sym->section->index] == NULL) + { + first_symbol[sym->section->index] = sym; + first_offset[sym->section->index] = addr + offset; + } + break; + case N_GSYM: + gdb_assert (oso_file != NULL); + if (first_symbol[sym->section->index] == NULL) + first_symbol[sym->section->index] = sym; + break; + case N_OSO: + gdb_assert (oso_file == NULL); + first_symbol = (asymbol **)xmalloc (nbr_sections + * sizeof (asymbol *)); + first_offset = (bfd_vma *)xmalloc (nbr_sections + * sizeof (bfd_vma)); + for (j = 0; j < nbr_sections; j++) + first_symbol[j] = NULL; + oso_file = sym; + break; + } + continue; + } + + if (sym->name == NULL || *sym->name == '\0') + { + /* Skip names that don't exist (shouldn't happen), or names + that are null strings (may happen). */ + continue; + } + + if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK)) + { + struct minimal_symbol *msym; + CORE_ADDR symaddr; + + /* Bfd symbols are section relative. */ + symaddr = sym->value + sym->section->vma; + + /* 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. */ + /* 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; + + if (sym->section == &bfd_abs_section) + ms_type = mst_abs; + else if (sym->section->flags & SEC_CODE) + { + if (sym->flags & (BSF_GLOBAL | BSF_WEAK)) + ms_type = mst_text; + else + ms_type = mst_file_text; + } + else if (sym->section->flags & SEC_ALLOC) + { + if (sym->flags & (BSF_GLOBAL | BSF_WEAK)) + { + if (sym->section->flags & SEC_LOAD) + ms_type = mst_data; + else + ms_type = mst_bss; + } + else if (sym->flags & BSF_LOCAL) + { + /* Not a special stabs-in-elf symbol, do regular + symbol processing. */ + if (sym->section->flags & SEC_LOAD) + ms_type = mst_file_data; + else + ms_type = mst_file_bss; + } + else + ms_type = mst_unknown; + } + else + continue; /* Skip this symbol. */ + + gdb_assert (sym->section->index < nbr_sections); + if (oso_file != NULL + && first_symbol[sym->section->index] == NULL) + { + first_symbol[sym->section->index] = sym; + first_offset[sym->section->index] = symaddr; + } + + msym = prim_record_minimal_symbol_and_info + (sym->name, symaddr, ms_type, sym->section->index, + sym->section, objfile); + } + } + + if (oso_file != NULL) + macho_add_oso (oso_file, nbr_sections, first_symbol, first_offset); +} + +/* If NAME describes an archive member (ie: ARCHIVE '(' MEMBER ')'), + returns the length of the archive name. + Returns -1 otherwise. */ +static int +get_archive_prefix_len (const char *name) +{ + char *lparen; + int name_len = strlen (name); + + if (name_len == 0 || name[name_len - 1] != ')') + return -1; + + lparen = strrchr (name, '('); + if (lparen == NULL || lparen == name) + return -1; + return lparen - name; +} + +/* Read symbols from the vector of oso files. */ +static void +macho_oso_symfile (struct objfile *main_objfile) +{ + int ix; + VEC (oso_el) *vec; + oso_el *oso; + char leading_char; + + /* TODO: Sort them, group library search. */ + + vec = oso_vector; + oso_vector = NULL; + + leading_char = bfd_get_symbol_leading_char (main_objfile->obfd); + + for (ix = 0; VEC_iterate (oso_el, vec, ix, oso); ix++) + { + struct section_addr_info *addrs; + int pfx_len; + int len; + int i; + oso_el el; + + if (mach_o_debug_level > 0) + printf_unfiltered (_("Loading symbols from oso: %s\n"), oso->name); + + /* Compute addr length. */ + len = 0; + for (i = 0; i < oso->num_sections; i++) + if (oso->symbols[i] != NULL) + len++; + + addrs = alloc_section_addr_info (len); + + len = 0; + for (i = 0; i < oso->num_sections; i++) + if (oso->symbols[i] != NULL) + { + if (oso->offsets[i]) + addrs->other[len].addr = oso->offsets[i]; + else + { + struct minimal_symbol *msym; + const char *name = oso->symbols[i]->name; + + if (name[0] == leading_char) + ++name; + + if (mach_o_debug_level > 3) + printf_unfiltered (_("resolv sec %s with %s\n"), + oso->symbols[i]->section->name, + oso->symbols[i]->name); + msym = lookup_minimal_symbol (name, NULL, main_objfile); + if (msym == NULL) + { + warning (_("can't find symbol '%s' in minsymtab"), + oso->symbols[i]->name); + addrs->other[len].addr = 0; + } + else + addrs->other[len].addr = SYMBOL_VALUE_ADDRESS (msym); + } + addrs->other[len].name = (char *)oso->symbols[i]->section->name; + len++; + } + + if (mach_o_debug_level > 1) + { + int j; + for (j = 0; j < addrs->num_sections; j++) + printf_unfiltered + (_(" %s: %s\n"), + core_addr_to_string (addrs->other[j].addr), + addrs->other[j].name); + } + + /* Check if this is a library name. */ + pfx_len = get_archive_prefix_len (oso->name); + if (pfx_len > 0) + { + bfd *archive_bfd; + bfd *member_bfd; + char *archive_name = (char *) alloca (pfx_len + 1); + int member_len; + + member_len = strlen (oso->name + pfx_len + 1) - 1; + memcpy (archive_name, oso->name, pfx_len); + archive_name[pfx_len] = '\0'; + + /* Open the archive and check the format. */ + archive_bfd = bfd_openr (archive_name, gnutarget); + if (archive_bfd == NULL) + { + warning (_("Could not open OSO archive file \"%s\""), + archive_name); + continue; + } + if (!bfd_check_format (archive_bfd, bfd_archive)) + { + warning (_("OSO archive file \"%s\" not an archive."), + archive_name); + bfd_close (archive_bfd); + continue; + } + member_bfd = bfd_openr_next_archived_file (archive_bfd, NULL); + + if (member_bfd == NULL) + { + warning (_("Could not read archive members out of " + "OSO archive \"%s\""), archive_name); + bfd_close (archive_bfd); + continue; + } + + while (member_bfd != NULL) + { + bfd *prev = member_bfd; + const char *member_name = member_bfd->filename; + if (strlen (member_name) == member_len + && !memcmp (member_name, oso->name + pfx_len + 1, member_len)) + break; + member_bfd = bfd_openr_next_archived_file + (archive_bfd, member_bfd); + bfd_close (prev); + } + if (member_bfd == NULL) + { + warning (_("Could not find specified archive member " + "for OSO name \"%s\""), oso->name); + bfd_close (archive_bfd); + continue; + } + + bfd_set_cacheable (member_bfd, 1); + + if (!bfd_check_format (member_bfd, bfd_object)) + { + warning (_("`%s': can't read symbols: %s."), oso->name, + bfd_errmsg (bfd_get_error ())); + bfd_close (member_bfd); + } + else + symbol_file_add_from_bfd (member_bfd, 0, addrs, 0, 0); + } + else + { + bfd *abfd; + + abfd = bfd_openr (oso->name, gnutarget); + if (!abfd) + { + warning (_("`%s': can't open to read symbols: %s."), oso->name, + bfd_errmsg (bfd_get_error ())); + continue; + } + bfd_set_cacheable (abfd, 1); + + if (!bfd_check_format (abfd, bfd_object)) + { + bfd_close (abfd); + warning (_("`%s': can't read symbols: %s."), oso->name, + bfd_errmsg (bfd_get_error ())); + continue; + } + + symbol_file_add_from_bfd (abfd, 0, addrs, 0, 0); + } + xfree (oso->symbols); + xfree (oso->offsets); + } + VEC_free (oso_el, vec); +} + +/* DSYM (debug symbols) files contain the debug info of an executable. + This is a separate file created by dsymutil(1) and is similar to debug + link feature on ELF. + DSYM files are located in a subdirectory. Append DSYM_SUFFIX to the + executable name and the executable base name to get the DSYM file name. */ +#define DSYM_SUFFIX ".dSYM/Contents/Resources/DWARF/" + +/* Check if a dsym file exists for OBJFILE. If so, returns a bfd for it. + Return NULL if no valid dsym file is found. */ +static bfd * +macho_check_dsym (struct objfile *objfile) +{ + size_t name_len = strlen (objfile->name); + size_t dsym_len = strlen (DSYM_SUFFIX); + const char *base_name = lbasename (objfile->name); + size_t base_len = strlen (base_name); + char *dsym_filename = alloca (name_len + dsym_len + base_len + 1); + bfd *dsym_bfd; + asection *sect; + bfd_byte main_uuid[16]; + bfd_byte dsym_uuid[16]; + + strcpy (dsym_filename, objfile->name); + strcpy (dsym_filename + name_len, DSYM_SUFFIX); + strcpy (dsym_filename + name_len + dsym_len, base_name); + + if (access (dsym_filename, R_OK) != 0) + return NULL; + + sect = bfd_get_section_by_name (objfile->obfd, "LC_UUID"); + if (sect == NULL) + { + warning (_("can't find UUID in %s"), objfile->name); + return NULL; + } + if (!bfd_get_section_contents (objfile->obfd, sect, main_uuid, + 0, sizeof (main_uuid))) + { + warning (_("can't read UUID in %s"), objfile->name); + return NULL; + } + + dsym_filename = xstrdup (dsym_filename); + dsym_bfd = bfd_openr (dsym_filename, gnutarget); + if (dsym_bfd == NULL) + { + warning (_("can't open dsym file %s"), dsym_filename); + xfree (dsym_filename); + return NULL; + } + + if (!bfd_check_format (dsym_bfd, bfd_object)) + { + bfd_close (dsym_bfd); + warning (_("bad dsym file format: %s"), bfd_errmsg (bfd_get_error ())); + xfree (dsym_filename); + return NULL; + } + + sect = bfd_get_section_by_name (dsym_bfd, "LC_UUID"); + if (sect == NULL) + { + warning (_("can't find UUID in %s"), dsym_filename); + bfd_close (dsym_bfd); + xfree (dsym_filename); + return NULL; + } + if (!bfd_get_section_contents (dsym_bfd, sect, dsym_uuid, + 0, sizeof (dsym_uuid))) + { + warning (_("can't read UUID in %s"), dsym_filename); + bfd_close (dsym_bfd); + xfree (dsym_filename); + return NULL; + } + if (memcmp (dsym_uuid, main_uuid, sizeof (main_uuid))) + { + warning (_("dsym file UUID doesn't match the one in %s"), objfile->name); + bfd_close (dsym_bfd); + xfree (dsym_filename); + return NULL; + } + return dsym_bfd; + +} + +static void +macho_symfile_read (struct objfile *objfile, int mainline) +{ + bfd *abfd = objfile->obfd; + struct cleanup *back_to; + CORE_ADDR offset; + long storage_needed; + bfd *dsym_bfd; + + init_minimal_symbol_collection (); + back_to = make_cleanup_discard_minimal_symbols (); + + /* Get symbols from the symbol table only if the file is an executable. + The symbol table of object files is not relocated and is expected to + be in the executable. */ + if (bfd_get_file_flags (abfd) & EXEC_P) + { + /* Process the normal symbol table first. */ + 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), + bfd_errmsg (bfd_get_error ())); + + if (storage_needed > 0) + { + asymbol **symbol_table; + long symcount; + + symbol_table = (asymbol **) xmalloc (storage_needed); + make_cleanup (xfree, symbol_table); + symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table); + + if (symcount < 0) + error (_("Can't read symbols from %s: %s"), + bfd_get_filename (objfile->obfd), + bfd_errmsg (bfd_get_error ())); + + macho_symtab_read (objfile, symcount, symbol_table); + } + + install_minimal_symbols (objfile); + + /* Check for DSYM file. */ + dsym_bfd = macho_check_dsym (objfile); + if (dsym_bfd != NULL) + { + int ix; + oso_el *oso; + + if (mach_o_debug_level > 0) + printf_unfiltered (_("dsym file found\n")); + + /* Remove oso. They won't be used. */ + for (ix = 0; VEC_iterate (oso_el, oso_vector, ix, oso); ix++) + { + xfree (oso->symbols); + xfree (oso->offsets); + } + VEC_free (oso_el, oso_vector); + oso_vector = NULL; + + /* Now recurse: read dwarf from dsym. */ + symbol_file_add_from_bfd (dsym_bfd, 0, NULL, 0, 0); + + /* Don't try to read dwarf2 from main file. */ + return; + } + } + + if (dwarf2_has_info (objfile)) + { + /* DWARF 2 sections */ + dwarf2_build_psymtabs (objfile, mainline); + } + + /* FIXME: kettenis/20030504: This still needs to be integrated with + dwarf2read.c in a better way. */ + dwarf2_build_frame_info (objfile); + + /* Then the oso. */ + if (oso_vector != NULL) + macho_oso_symfile (objfile); +} + +static void +macho_symfile_finish (struct objfile *objfile) +{ +} + +static void +macho_symfile_offsets (struct objfile *objfile, + struct section_addr_info *addrs) +{ + unsigned int i; + unsigned int num_sections; + struct obj_section *osect; + + /* Allocate section_offsets. */ + objfile->num_sections = bfd_count_sections (objfile->obfd); + objfile->section_offsets = (struct section_offsets *) + obstack_alloc (&objfile->objfile_obstack, + SIZEOF_N_SECTION_OFFSETS (objfile->num_sections)); + memset (objfile->section_offsets, 0, + SIZEOF_N_SECTION_OFFSETS (objfile->num_sections)); + + /* This code is run when we first add the objfile with + symfile_add_with_addrs_or_offsets, when "addrs" not "offsets" are + passed in. The place in symfile.c where the addrs are applied + depends on the addrs having section names. But in the dyld code + we build an anonymous array of addrs, so that code is a no-op. + Because of that, we have to apply the addrs to the sections here. + N.B. if an objfile slides after we've already created it, then it + goes through objfile_relocate. */ + + for (i = 0; i < addrs->num_sections; i++) + { + if (addrs->other[i].name == NULL) + continue; + + ALL_OBJFILE_OSECTIONS (objfile, osect) + { + const char *bfd_sect_name = osect->the_bfd_section->name; + + if (strcmp (bfd_sect_name, addrs->other[i].name) == 0) + { + obj_section_offset (osect) = addrs->other[i].addr; + break; + } + } + } + + objfile->sect_index_text = 0; + + ALL_OBJFILE_OSECTIONS (objfile, osect) + { + const char *bfd_sect_name = osect->the_bfd_section->name; + int sect_index = osect->the_bfd_section->index; + + if (strcmp (bfd_sect_name, "LC_SEGMENT.__TEXT") == 0) + objfile->sect_index_text = sect_index; + else if (strcmp (bfd_sect_name, "LC_SEGMENT.__TEXT.__text") == 0) + objfile->sect_index_text = sect_index; + } +} + +static struct sym_fns macho_sym_fns = { + bfd_target_mach_o_flavour, + + macho_new_init, /* sym_new_init: init anything gbl to entire symtab */ + macho_symfile_init, /* sym_init: read initial info, setup for sym_read() */ + macho_symfile_read, /* sym_read: read a symbol file into symtab */ + macho_symfile_finish, /* sym_finish: finished with file, cleanup */ + macho_symfile_offsets, /* sym_offsets: xlate external to internal form */ + NULL /* next: pointer to next struct sym_fns */ +}; + +void +_initialize_machoread () +{ + add_symtab_fns (&macho_sym_fns); + + add_setshow_zinteger_cmd ("mach-o", class_obscure, + &mach_o_debug_level, _("\ +Set if printing Mach-O symbols processing."), _("\ +Show if printing Mach-O symbols processing."), NULL, + NULL, NULL, + &setdebuglist, &showdebuglist); +} |