979 lines
28 KiB
C
979 lines
28 KiB
C
/* LTO routines for Mach-O object files.
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Copyright 2010 Free Software Foundation, Inc.
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Contributed by Steven Bosscher.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "toplev.h"
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#include "lto.h"
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#include "tm.h"
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#include "libiberty.h"
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#include "lto-streamer.h"
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#include "lto/lto-endian.h"
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#include "lto/lto-macho.h"
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/* Rather than implementing a libmacho to match libelf, or attempting to
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integrate libbfd into GCC, this file is a self-contained (and very
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minimal) Mach-O format object file reader/writer. The generated files
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will contain a Mach-O header, a number of Mach-O load commands an
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section headers, the section data itself, and a trailing string table
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for section names. */
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/* This needs to be kept in sync with darwin.c. Better yet, lto-macho.c
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and lto-macho.h should be moved to config/, and likewise for lto-coff.*
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and lto-elf.*. */
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/* Segment name for LTO sections. */
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#define LTO_SEGMENT_NAME "__GNU_LTO"
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/* Section name for LTO section names section. */
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#define LTO_NAMES_SECTION "__section_names"
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/* Handle opening elf files on hosts, such as Windows, that may use
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text file handling that will break binary access. */
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#ifndef O_BINARY
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# define O_BINARY 0
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#endif
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/* Cached object file header. We use a header_64 for this, since all
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the fields we need are in there, in the same position as header_32. */
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mach_o_header_64 cached_mach_o_header;
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uint32_t cached_mach_o_magic;
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/* The current output file. */
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static lto_file *current_out_file;
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/* Is this a 32-bits or 64-bits Mach-O object file? */
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static int
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mach_o_word_size (void)
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{
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gcc_assert (cached_mach_o_magic != 0);
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return (cached_mach_o_magic == MACH_O_MH_MAGIC_64
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|| cached_mach_o_magic == MACH_O_MH_CIGAM_64) ? 64 : 32;
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}
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/* Sets the current output file to FILE. Returns the old output file or
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NULL. */
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lto_file *
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lto_set_current_out_file (lto_file *file)
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{
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lto_file *old_file = current_out_file;
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current_out_file = file;
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return old_file;
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}
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/* Returns the current output file. */
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lto_file *
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lto_get_current_out_file (void)
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{
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return current_out_file;
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}
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/* Mach-O section structure constructor. */
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static lto_mach_o_section
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mach_o_new_section (lto_mach_o_file *mach_o_file, const char *name)
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{
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lto_mach_o_section ptr;
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/* FIXME We could allocate these things on an obstack. */
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ptr = XCNEW (struct lto_mach_o_section_d);
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if (name)
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{
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if (strncmp (name, LTO_SECTION_NAME_PREFIX,
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strlen(LTO_SECTION_NAME_PREFIX)) != 0)
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sorry ("not implemented: Mach-O writer for non-LTO sections");
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ptr->name = xstrdup (name);
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}
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VEC_safe_push (lto_mach_o_section, heap, mach_o_file->section_vec, ptr);
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return ptr;
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}
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/* Mach-O section data block structure constructor. */
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static lto_mach_o_data
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mach_o_new_data (lto_mach_o_section sec)
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{
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lto_mach_o_data ptr, *chain_ptr_ptr;
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/* FIXME We could allocate these things on an obstack. */
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ptr = XCNEW (struct lto_mach_o_data_d);
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chain_ptr_ptr = &sec->data_chain;
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while (*chain_ptr_ptr)
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chain_ptr_ptr = &(*chain_ptr_ptr)->next;
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*chain_ptr_ptr = ptr;
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return ptr;
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}
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/* Initialize FILE, an LTO file object for FILENAME. Offset is the
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offset into FILE where the object is located (e.g. in an archive). */
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static void
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lto_file_init (lto_file *file, const char *filename, off_t offset)
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{
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file->filename = filename;
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file->offset = offset;
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}
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/* Return an error string after an error, or a predetermined one
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if ERRCODE is not -1. */
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static const char *
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mach_o_errmsg (int errcode)
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{
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return strerror (errcode == -1 ? errno : errcode);
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}
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/* Returns a hash code for P. */
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static hashval_t
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hash_name (const void *p)
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{
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const struct lto_section_slot *s = (const struct lto_section_slot *) p;
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return (hashval_t) htab_hash_string (s->name);
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}
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/* Returns nonzero if P1 and P2 are equal. */
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static int
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eq_name (const void *p1, const void *p2)
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{
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const struct lto_section_slot *s1 =
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(const struct lto_section_slot *) p1;
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const struct lto_section_slot *s2 =
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(const struct lto_section_slot *) p2;
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return strcmp (s1->name, s2->name) == 0;
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}
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/* Build a hash table whose key is the section names and whose data is
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the start and size of each section in the .o file. */
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htab_t
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lto_obj_build_section_table (lto_file *lto_file)
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{
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lto_mach_o_file *mach_o_file = (lto_mach_o_file *)lto_file;
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lto_mach_o_section sec;
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htab_t section_hash_table;
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off_t strtab_offs;
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ssize_t strtab_size;
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char *strtab = NULL;
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int i;
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section_hash_table = htab_create (37, hash_name, eq_name, free);
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/* Seek the string table. */
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/* FIXME The segment name should be in darwin.h, but can we include it
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here in this file? */
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for (i = 0;
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VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
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i++)
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{
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if (strncmp (sec->u.section.segname, "__GNU_LTO", 16) != 0)
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continue;
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if (strncmp (sec->u.section.sectname, "__section_names", 16) == 0)
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break;
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}
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if (! sec)
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{
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error ("invalid Mach-O LTO object file: no __section_names section found");
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goto done;
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}
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mach_o_file->section_names_section = sec;
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if (mach_o_word_size () == 64)
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{
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strtab_offs = (off_t) get_uint32 (&sec->u.section_64.offset[0]);
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strtab_size = (size_t) get_uint64 (&sec->u.section_64.size[0]);
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}
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else
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{
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strtab_offs = (off_t) get_uint32 (&sec->u.section_32.offset[0]);
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strtab_size = (size_t) get_uint32 (&sec->u.section_32.size[0]);
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}
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/* Seek to start of string table. */
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if (strtab_offs != lseek (mach_o_file->fd,
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mach_o_file->base.offset + strtab_offs,
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SEEK_SET))
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{
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error ("altered or invalid Mach-O object file");
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goto done;
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}
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strtab = XNEWVEC (char, strtab_size);
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if (read (mach_o_file->fd, strtab, strtab_size) != strtab_size)
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{
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error ("invalid Mach-O LTO object file __section_names section");
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goto done;
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}
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/* Scan sections looking at names. */
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for (i = 0;
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VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
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i++)
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{
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struct lto_section_slot s_slot;
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void **slot;
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char *new_name;
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unsigned long stringoffset;
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char name[17];
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/* Ignore non-LTO sections. Also ignore the __section_names section
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which does not need renaming. */
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if (strncmp (sec->u.section.segname, "__GNU_LTO", 16) != 0)
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continue;
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if (sec == mach_o_file->section_names_section)
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continue;
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/* Try to extract the offset of the real name for this section from
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__section_names. */
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memcpy (&name[0], sec->u.section.sectname, 16);
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name[16] = '\0';
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if (name[0] != '_' || name[1] != '_'
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|| sscanf (&name[2], "%08lX", &stringoffset) != 1
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|| strtab_size < (ssize_t) stringoffset)
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{
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error ("invalid Mach-O LTO section name string: %s", name);
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continue;
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}
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new_name = XNEWVEC (char, strlen (strtab + stringoffset) + 1);
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strcpy (new_name, strtab + stringoffset);
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s_slot.name = new_name;
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slot = htab_find_slot (section_hash_table, &s_slot, INSERT);
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if (*slot == NULL)
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{
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struct lto_section_slot *new_slot = XNEW (struct lto_section_slot);
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new_slot->name = new_name;
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if (mach_o_word_size() == 64)
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{
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new_slot->start =
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(intptr_t) get_uint32 (&sec->u.section_64.offset[0]);
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new_slot->len =
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(size_t) get_uint64 (&sec->u.section_64.size[0]);
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}
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else
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{
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new_slot->start =
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(intptr_t) get_uint32 (&sec->u.section_32.offset[0]);
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new_slot->len =
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(size_t) get_uint32 (&sec->u.section_32.size[0]);
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}
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*slot = new_slot;
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}
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else
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{
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error ("two or more sections for %s:", new_name);
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goto done;
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}
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}
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done:
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if (strtab)
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free (strtab);
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return section_hash_table;
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}
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/* Begin a new Mach-O section named NAME in the current output file. */
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void
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lto_obj_begin_section (const char *name)
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{
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lto_mach_o_file *file;
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if (strncmp (name, LTO_SECTION_NAME_PREFIX,
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strlen(LTO_SECTION_NAME_PREFIX)) != 0)
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sorry ("not implemented: Mach-O writer for non-LTO sections");
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/* Grab the current output file and do some basic assertion checking. */
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file = (lto_mach_o_file *) lto_get_current_out_file (),
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gcc_assert (file && file->writable && !file->scn);
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/* Create a new section. */
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file->scn = mach_o_new_section (file, name);
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if (!file->scn)
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fatal_error ("could not create a new Mach-O section: %s", mach_o_errmsg (-1));
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}
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/* Append DATA of length LEN to the current output section. BASE is a pointer
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to the output page containing DATA. It is freed once the output file has
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been written. */
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void
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lto_obj_append_data (const void *data, size_t len, void *block)
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{
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lto_mach_o_file *file;
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lto_mach_o_data mach_o_data;
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struct lto_char_ptr_base *base = (struct lto_char_ptr_base *) block;
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/* Grab the current output file and do some basic assertion checking. */
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file = (lto_mach_o_file *) lto_get_current_out_file ();
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gcc_assert (file);
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gcc_assert (file->scn);
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mach_o_data = mach_o_new_data (file->scn);
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if (!mach_o_data)
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fatal_error ("could not append data to Mach-O section: %s", mach_o_errmsg (-1));
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mach_o_data->d_buf = CONST_CAST (void *, data);
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mach_o_data->d_size = len;
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/* Chain all data blocks (from all sections) on one singly-linked
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list for freeing en masse after the file is closed. */
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base->ptr = (char *)file->data;
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file->data = base;
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}
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|
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/* End the current output section. This just does some assertion checking
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and sets the current output file's scn member to NULL. */
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void
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lto_obj_end_section (void)
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{
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lto_mach_o_file *file;
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/* Grab the current output file and validate some basic assertions. */
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file = (lto_mach_o_file *) lto_get_current_out_file ();
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gcc_assert (file);
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gcc_assert (file->scn);
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|
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file->scn = NULL;
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}
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|
|
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/* Read a Mach-O header from MACH_O_FILE and validate it.
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The file descriptor in MACH_O_FILE points at the start of the file.
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If cached_mach_o_header is uninitialized, caches the results.
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On succes, returns true and moves file pointer to the start of the
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load commands. On failure, returns false. */
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static bool
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validate_mach_o_header (lto_mach_o_file *mach_o_file)
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{
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ssize_t i, n;
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unsigned char magic[4];
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uint32_t cputype;
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off_t startpos;
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|
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/* Known header magics for validation, as an array. */
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static const unsigned int mach_o_known_formats[] = {
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MACH_O_MH_MAGIC,
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MACH_O_MH_CIGAM,
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MACH_O_MH_MAGIC_64,
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MACH_O_MH_CIGAM_64,
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};
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#define MACH_O_NUM_KNOWN_FORMATS \
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((ssize_t) ARRAY_SIZE (mach_o_known_formats))
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|
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startpos = lseek (mach_o_file->fd, 0, SEEK_CUR);
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if (read (mach_o_file->fd, &magic, sizeof (magic)) != 4
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|| lseek (mach_o_file->fd, -4, SEEK_CUR) != startpos)
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{
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error ("cannot read file %s", mach_o_file->base.filename);
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return false;
|
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}
|
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|
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for (i = 0; i < MACH_O_NUM_KNOWN_FORMATS; ++i)
|
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if (get_uint32 (&magic[0]) == mach_o_known_formats[i])
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break;
|
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if (i == MACH_O_NUM_KNOWN_FORMATS)
|
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goto not_for_target;
|
|
|
|
/* Check the endian-ness. */
|
|
if (BYTES_BIG_ENDIAN && magic[0] != 0xfe)
|
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goto not_for_target;
|
|
|
|
/* Set or check cached magic number. */
|
|
if (cached_mach_o_magic == 0)
|
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cached_mach_o_magic = get_uint32 (&magic[0]);
|
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else if (cached_mach_o_magic != get_uint32 (&magic[0]))
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|
goto not_for_target;
|
|
|
|
n = mach_o_word_size () == 64
|
|
? sizeof (mach_o_header_64) : sizeof (mach_o_header_32);
|
|
if (read (mach_o_file->fd, &mach_o_file->u.header, n) != n)
|
|
goto not_for_target;
|
|
|
|
/* Is this a supported CPU? */
|
|
/* ??? Would be nice to validate the exact target architecture. */
|
|
cputype = get_uint32 (&mach_o_file->u.header.cputype[0]);
|
|
if (cputype == MACH_O_CPU_TYPE_I386
|
|
|| cputype == MACH_O_CPU_TYPE_POWERPC)
|
|
{
|
|
if (mach_o_word_size () != 32)
|
|
goto not_for_target;
|
|
}
|
|
else if (cputype == MACH_O_CPU_TYPE_X86_64
|
|
|| cputype == MACH_O_CPU_TYPE_POWERPC_64)
|
|
{
|
|
if (mach_o_word_size () != 64)
|
|
goto not_for_target;
|
|
}
|
|
|
|
/* Is this an MH_OBJECT file? */
|
|
if (get_uint32 (&mach_o_file->u.header.filetype[0]) != MACH_O_MH_OBJECT)
|
|
error ("Mach-O file %s is not an MH_OBJECT file",
|
|
mach_o_file->base.filename);
|
|
|
|
/* Save the header for future use. */
|
|
memcpy (&cached_mach_o_header, &mach_o_file->u.header,
|
|
sizeof (cached_mach_o_header));
|
|
|
|
return true;
|
|
|
|
not_for_target:
|
|
error ("file %s is not a Mach-O object file for target",
|
|
mach_o_file->base.filename);
|
|
return false;
|
|
}
|
|
|
|
|
|
/* Read a Mach-O LC_SEGMENT command (32 bits) from MACH_O_FILE and
|
|
validate it.
|
|
The file descriptor in MACH_O_FILE points at the start of the load
|
|
command. On sucess, returns true and advances the file pointer
|
|
past the end of the load command. On failure, returns false. */
|
|
|
|
static bool
|
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validate_mach_o_segment_command_32 (lto_mach_o_file *mach_o_file)
|
|
{
|
|
mach_o_segment_command_32 seg_cmd_32;
|
|
unsigned int i;
|
|
ssize_t n;
|
|
off_t startpos;
|
|
|
|
/* Fields we're interested in. */
|
|
uint32_t cmd;
|
|
uint32_t cmdsize;
|
|
uint32_t nsects;
|
|
|
|
startpos = lseek (mach_o_file->fd, 0, SEEK_CUR);
|
|
|
|
n = sizeof (mach_o_segment_command_32);
|
|
if (read (mach_o_file->fd, (void *) &seg_cmd_32, n) != n)
|
|
goto fail;
|
|
|
|
cmd = get_uint32 (&seg_cmd_32.cmd[0]);
|
|
cmdsize = get_uint32 (&seg_cmd_32.cmdsize[0]);
|
|
nsects = get_uint32 (&seg_cmd_32.nsects[0]);
|
|
gcc_assert (cmd == MACH_O_LC_SEGMENT);
|
|
|
|
/* Validate section table entries. */
|
|
for (i = 0; i < nsects; i++)
|
|
{
|
|
mach_o_section_32 sec_32;
|
|
lto_mach_o_section ltosec;
|
|
|
|
n = sizeof (mach_o_section_32);
|
|
if (read (mach_o_file->fd, &sec_32, n) != n)
|
|
goto fail;
|
|
|
|
/* ??? Perform some checks. */
|
|
|
|
/* Looks ok, so record its details. We don't read the
|
|
string table or set up names yet; we'll do that when
|
|
we build the hash table. */
|
|
ltosec = mach_o_new_section (mach_o_file, NULL);
|
|
memcpy (<osec->u.section_32, &sec_32, sizeof (sec_32));
|
|
}
|
|
|
|
if (lseek (mach_o_file->fd, 0, SEEK_CUR) != startpos + cmdsize)
|
|
goto fail;
|
|
|
|
return true;
|
|
|
|
fail:
|
|
error ("could not read LC_SEGMENT command in Mach-O file %s",
|
|
mach_o_file->base.filename);
|
|
return false;
|
|
}
|
|
|
|
|
|
/* Read a Mach-O LC_SEGMENT_64 command from MACH_O_FILE and validate it.
|
|
The file descriptor in MACH_O_FILE points at the start of the load
|
|
command. On sucess, returns true and advances the file pointer
|
|
past the end of the load command. On failure, returns false. */
|
|
|
|
static bool
|
|
validate_mach_o_segment_command_64 (lto_mach_o_file *mach_o_file)
|
|
{
|
|
mach_o_segment_command_64 seg_cmd_64;
|
|
unsigned int i;
|
|
ssize_t n;
|
|
off_t startpos;
|
|
|
|
/* Fields we're interested in. */
|
|
uint32_t cmd;
|
|
uint32_t cmdsize;
|
|
uint32_t nsects;
|
|
|
|
startpos = lseek (mach_o_file->fd, 0, SEEK_CUR);
|
|
|
|
n = sizeof (mach_o_segment_command_64);
|
|
if (read (mach_o_file->fd, (void *) &seg_cmd_64, n) != n)
|
|
goto fail;
|
|
|
|
cmd = get_uint32 (&seg_cmd_64.cmd[0]);
|
|
cmdsize = get_uint32 (&seg_cmd_64.cmdsize[0]);
|
|
nsects = get_uint32 (&seg_cmd_64.nsects[0]);
|
|
gcc_assert (cmd == MACH_O_LC_SEGMENT_64);
|
|
|
|
/* Validate section table entries. */
|
|
for (i = 0; i < nsects; i++)
|
|
{
|
|
mach_o_section_64 sec_64;
|
|
lto_mach_o_section ltosec;
|
|
|
|
n = sizeof (mach_o_section_64);
|
|
if (read (mach_o_file->fd, &sec_64, n) != n)
|
|
goto fail;
|
|
|
|
/* ??? Perform some checks. */
|
|
|
|
/* Looks ok, so record its details. We don't read the
|
|
string table or set up names yet; we'll do that when
|
|
we build the hash table. */
|
|
ltosec = mach_o_new_section (mach_o_file, NULL);
|
|
memcpy (<osec->u.section_64, &sec_64, sizeof (sec_64));
|
|
}
|
|
|
|
if (lseek (mach_o_file->fd, 0, SEEK_CUR) != startpos + cmdsize)
|
|
goto fail;
|
|
|
|
return true;
|
|
|
|
fail:
|
|
error ("could not read LC_SEGMENT_64 command in Mach-O file %s",
|
|
mach_o_file->base.filename);
|
|
return false;
|
|
}
|
|
|
|
/* Read a Mach-O load commands from MACH_O_FILE and validate it.
|
|
The file descriptor in MACH_O_FILE points at the start of the load
|
|
command. On sucess, returns true and advances the file pointer
|
|
past the end of the load command. On failure, returns false. */
|
|
|
|
static bool
|
|
validate_mach_o_load_command (lto_mach_o_file *mach_o_file)
|
|
{
|
|
mach_o_load_command load_command;
|
|
uint32_t cmd;
|
|
uint32_t cmdsize;
|
|
ssize_t n;
|
|
|
|
n = sizeof (load_command);
|
|
if (read (mach_o_file->fd, &load_command, n) != n)
|
|
{
|
|
error ("could not read load commands in Mach-O file %s",
|
|
mach_o_file->base.filename);
|
|
return false;
|
|
}
|
|
lseek (mach_o_file->fd, -1 * (off_t) sizeof (load_command), SEEK_CUR);
|
|
|
|
cmd = get_uint32 (&load_command.cmd[0]);
|
|
cmdsize = get_uint32 (&load_command.cmdsize[0]);
|
|
switch (cmd)
|
|
{
|
|
case MACH_O_LC_SEGMENT:
|
|
return validate_mach_o_segment_command_32 (mach_o_file);
|
|
case MACH_O_LC_SEGMENT_64:
|
|
return validate_mach_o_segment_command_64 (mach_o_file);
|
|
|
|
default:
|
|
/* Just skip over it. */
|
|
lseek (mach_o_file->fd, cmdsize, SEEK_CUR);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/* Validate's MACH_O_FILE's executable header and, if cached_mach_o_header is
|
|
uninitialized, caches the results. Also records the section header string
|
|
table's section index. Returns true on success, false on failure. */
|
|
|
|
static bool
|
|
validate_file (lto_mach_o_file *mach_o_file)
|
|
{
|
|
uint32_t i, ncmds;
|
|
|
|
/* Read and sanity check the raw header. */
|
|
if (! validate_mach_o_header (mach_o_file))
|
|
return false;
|
|
|
|
ncmds = get_uint32 (&mach_o_file->u.header.ncmds[0]);
|
|
for (i = 0; i < ncmds; ++i)
|
|
if (! validate_mach_o_load_command (mach_o_file))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/* Initialize MACH_O_FILE's executable header using cached data from previously
|
|
read files. */
|
|
|
|
static void
|
|
init_mach_o_header (lto_mach_o_file *mach_o_file)
|
|
{
|
|
gcc_assert (cached_mach_o_magic != 0);
|
|
memcpy (&mach_o_file->u.header,
|
|
&cached_mach_o_header,
|
|
sizeof (mach_o_file->u.header));
|
|
put_uint32 (&mach_o_file->u.header.ncmds[0], 0);
|
|
put_uint32 (&mach_o_file->u.header.sizeofcmds[0], 0);
|
|
}
|
|
|
|
/* Open Mach-O file FILENAME. If WRITABLE is true, the file is opened for write
|
|
and, if necessary, created. Otherwise, the file is opened for reading.
|
|
Returns the opened file. */
|
|
|
|
lto_file *
|
|
lto_obj_file_open (const char *filename, bool writable)
|
|
{
|
|
lto_mach_o_file *mach_o_file;
|
|
lto_file *result = NULL;
|
|
off_t offset;
|
|
const char *offset_p;
|
|
char *fname;
|
|
struct stat statbuf;
|
|
|
|
offset_p = strchr (filename, '@');
|
|
if (!offset_p)
|
|
{
|
|
fname = xstrdup (filename);
|
|
offset = 0;
|
|
}
|
|
else
|
|
{
|
|
/* The file started with '@' is a file containing command line
|
|
options. Stop if it doesn't exist. */
|
|
if (offset_p == filename)
|
|
fatal_error ("command line option file '%s' does not exist",
|
|
filename);
|
|
|
|
fname = (char *) xmalloc (offset_p - filename + 1);
|
|
memcpy (fname, filename, offset_p - filename);
|
|
fname[offset_p - filename] = '\0';
|
|
offset_p += 3; /* skip the @0x */
|
|
offset = lto_parse_hex (offset_p);
|
|
}
|
|
|
|
/* Set up. */
|
|
mach_o_file = XCNEW (lto_mach_o_file);
|
|
result = (lto_file *) mach_o_file;
|
|
lto_file_init (result, fname, offset);
|
|
mach_o_file->fd = -1;
|
|
mach_o_file->writable = writable;
|
|
|
|
/* Open the file. */
|
|
mach_o_file->fd = open (fname,
|
|
O_BINARY | (writable ? O_WRONLY | O_CREAT | O_TRUNC : O_RDONLY), 0666);
|
|
|
|
if (mach_o_file->fd == -1)
|
|
{
|
|
error ("could not open file %s", fname);
|
|
goto fail;
|
|
}
|
|
|
|
if (stat (fname, &statbuf) < 0)
|
|
{
|
|
error ("could not stat file %s", fname);
|
|
goto fail;
|
|
}
|
|
|
|
mach_o_file->file_size = statbuf.st_size;
|
|
|
|
/* If the object is in an archive, get it out. */
|
|
if (offset != 0)
|
|
{
|
|
char ar_tail[12];
|
|
int size;
|
|
|
|
/* Surely not? */
|
|
gcc_assert (!writable);
|
|
|
|
/* Seek to offset, or error. */
|
|
if (lseek (mach_o_file->fd, offset, SEEK_SET) != (ssize_t) offset)
|
|
{
|
|
error ("could not find archive member @0x%lx", (long) offset);
|
|
goto fail;
|
|
}
|
|
|
|
/* Now seek back 12 chars and read the tail of the AR header to
|
|
find the length of the member file. */
|
|
if (lseek (mach_o_file->fd, -12, SEEK_CUR) < 0
|
|
|| read (mach_o_file->fd, ar_tail, 12) != 12
|
|
|| lseek (mach_o_file->fd, 0, SEEK_CUR) != (ssize_t) offset
|
|
|| ar_tail[10] != '`' || ar_tail[11] != '\n')
|
|
{
|
|
error ("could not find archive header @0x%lx", (long) offset);
|
|
goto fail;
|
|
}
|
|
|
|
ar_tail[11] = 0;
|
|
if (sscanf (ar_tail, "%d", &size) != 1)
|
|
{
|
|
error ("invalid archive header @0x%lx", (long) offset);
|
|
goto fail;
|
|
}
|
|
mach_o_file->file_size = size;
|
|
}
|
|
|
|
if (writable)
|
|
{
|
|
init_mach_o_header (mach_o_file);
|
|
}
|
|
else
|
|
if (! validate_file (mach_o_file))
|
|
goto fail;
|
|
|
|
return result;
|
|
|
|
fail:
|
|
if (result)
|
|
lto_obj_file_close (result);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/* Write the data in MACH_O_FILE to a real Mach-O binary object.
|
|
We write a header, a segment load command, and section data. */
|
|
|
|
static bool
|
|
mach_o_write_object_file (lto_mach_o_file *mach_o_file)
|
|
{
|
|
lto_mach_o_section sec, snsec;
|
|
lto_mach_o_data snsec_data;
|
|
ssize_t hdrsize, cmdsize, secsize;
|
|
size_t num_sections, snsec_size, total_sec_size;
|
|
unsigned int sec_offs, strtab_offs;
|
|
int i;
|
|
bool write_err = false;
|
|
|
|
/* The number of sections we will write is the number of sections added by
|
|
the streamer, plus 1 for the section names section. */
|
|
num_sections = VEC_length (lto_mach_o_section, mach_o_file->section_vec) + 1;
|
|
|
|
/* Calculate the size of the basic data structures on disk. */
|
|
if (mach_o_word_size () == 64)
|
|
{
|
|
hdrsize = sizeof (mach_o_header_64);
|
|
secsize = sizeof (mach_o_section_64);
|
|
cmdsize = sizeof (mach_o_segment_command_64) + num_sections * secsize;
|
|
}
|
|
else
|
|
{
|
|
hdrsize = sizeof (mach_o_header_32);
|
|
secsize = sizeof (mach_o_section_32);
|
|
cmdsize = sizeof (mach_o_segment_command_32) + num_sections * secsize;
|
|
}
|
|
|
|
/* Allocate the section names section. */
|
|
snsec_size = 0;
|
|
for (i = 0;
|
|
VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
|
|
i++)
|
|
snsec_size += strlen (sec->name) + 1;
|
|
snsec = mach_o_new_section (mach_o_file, NULL);
|
|
snsec->name = LTO_NAMES_SECTION;
|
|
snsec_data = mach_o_new_data (snsec);
|
|
snsec_data->d_buf = XCNEWVEC (char, snsec_size);
|
|
snsec_data->d_size = snsec_size;
|
|
|
|
/* Position all the sections, and fill out their headers. */
|
|
sec_offs = hdrsize + cmdsize;
|
|
strtab_offs = 0;
|
|
total_sec_size = 0;
|
|
for (i = 0;
|
|
VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
|
|
i++)
|
|
{
|
|
lto_mach_o_data data;
|
|
size_t data_size;
|
|
/* Put the section and segment names. Add the section name to the
|
|
section names section (unless, of course, this *is* the section
|
|
names section). */
|
|
if (sec == snsec)
|
|
snprintf (sec->u.section.sectname, 16, "%s", LTO_NAMES_SECTION);
|
|
else
|
|
{
|
|
sprintf (sec->u.section.sectname, "__%08X", strtab_offs);
|
|
memcpy ((char *) snsec_data->d_buf + strtab_offs, sec->name, strlen (sec->name));
|
|
}
|
|
memcpy (&sec->u.section.segname[0],
|
|
LTO_SEGMENT_NAME, strlen (LTO_SEGMENT_NAME));
|
|
|
|
/* Add layout and attributes. */
|
|
for (data = sec->data_chain, data_size = 0; data; data = data->next)
|
|
data_size += data->d_size;
|
|
if (mach_o_word_size () == 64)
|
|
{
|
|
put_uint64 (&sec->u.section_64.addr[0], total_sec_size);
|
|
put_uint64 (&sec->u.section_64.size[0], data_size);
|
|
put_uint32 (&sec->u.section_64.offset[0], sec_offs);
|
|
put_uint32 (&sec->u.section_64.flags[0], MACH_O_S_ATTR_DEBUG);
|
|
}
|
|
else
|
|
{
|
|
put_uint32 (&sec->u.section_64.addr[0], total_sec_size);
|
|
put_uint32 (&sec->u.section_32.size[0], data_size);
|
|
put_uint32 (&sec->u.section_32.offset[0], sec_offs);
|
|
put_uint32 (&sec->u.section_32.flags[0], MACH_O_S_ATTR_DEBUG);
|
|
}
|
|
|
|
sec_offs += data_size;
|
|
total_sec_size += data_size;
|
|
strtab_offs += strlen (sec->name) + 1;
|
|
}
|
|
|
|
/* We can write the data now. As there's no way to indicate an error return
|
|
from this hook, error handling is limited to not wasting our time doing
|
|
any more writes in the event that any one fails. */
|
|
|
|
/* Write the header. */
|
|
put_uint32 (&mach_o_file->u.header.ncmds[0], 1);
|
|
put_uint32 (&mach_o_file->u.header.sizeofcmds[0], cmdsize);
|
|
write_err = (write (mach_o_file->fd,
|
|
&mach_o_file->u.header, hdrsize) != hdrsize);
|
|
/* Write the segment load command. */
|
|
if (mach_o_word_size () == 64)
|
|
{
|
|
mach_o_segment_command_64 lc;
|
|
ssize_t lc_size = sizeof (lc);
|
|
memset (&lc, 0, lc_size);
|
|
put_uint32 (&lc.cmd[0], MACH_O_LC_SEGMENT_64);
|
|
put_uint32 (&lc.cmdsize[0], cmdsize);
|
|
put_uint64 (&lc.fileoff[0], hdrsize + cmdsize);
|
|
put_uint64 (&lc.filesize[0], total_sec_size);
|
|
put_uint32 (&lc.nsects[0], num_sections);
|
|
write_err = (write (mach_o_file->fd, &lc, lc_size) != lc_size);
|
|
}
|
|
else
|
|
{
|
|
mach_o_segment_command_32 lc;
|
|
ssize_t lc_size = sizeof (lc);
|
|
memset (&lc, 0, lc_size);
|
|
put_uint32 (&lc.cmd[0], MACH_O_LC_SEGMENT);
|
|
put_uint32 (&lc.cmdsize[0], cmdsize);
|
|
put_uint32 (&lc.fileoff[0], hdrsize + cmdsize);
|
|
put_uint32 (&lc.filesize[0], total_sec_size);
|
|
put_uint32 (&lc.nsects[0], num_sections);
|
|
write_err = (write (mach_o_file->fd, &lc, lc_size) != lc_size);
|
|
}
|
|
for (i = 0;
|
|
!write_err
|
|
&& VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
|
|
i++)
|
|
write_err = (write (mach_o_file->fd,
|
|
&sec->u.section, secsize) != secsize);
|
|
|
|
gcc_assert (lseek (mach_o_file->fd, 0, SEEK_CUR) == hdrsize + cmdsize);
|
|
|
|
/* Write the section data. */
|
|
for (i = 0;
|
|
!write_err
|
|
&& VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
|
|
i++)
|
|
{
|
|
lto_mach_o_data data;
|
|
|
|
for (data = sec->data_chain; data; data = data->next)
|
|
{
|
|
if (!write_err)
|
|
write_err = (write (mach_o_file->fd, data->d_buf, data->d_size)
|
|
!= data->d_size);
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
|
|
return !write_err;
|
|
}
|
|
|
|
/* Close Mach-O file FILE and clean up any associated data structures. If FILE
|
|
was opened for writing, the file's Mach-O data is written at this time. Any
|
|
cached data buffers are freed. */
|
|
|
|
void
|
|
lto_obj_file_close (lto_file *file)
|
|
{
|
|
lto_mach_o_file *mach_o_file = (lto_mach_o_file *) file;
|
|
struct lto_char_ptr_base *cur, *tmp;
|
|
lto_mach_o_section sec;
|
|
bool write_err = false;
|
|
int i;
|
|
|
|
/* If this file is open for writing, write a Mach-O object file. */
|
|
if (mach_o_file->writable)
|
|
{
|
|
if (! mach_o_write_object_file (mach_o_file))
|
|
fatal_error ("cannot write Mach-O object file");
|
|
}
|
|
|
|
/* Close the file, we're done. */
|
|
if (mach_o_file->fd != -1)
|
|
close (mach_o_file->fd);
|
|
|
|
/* Free any data buffers. */
|
|
cur = mach_o_file->data;
|
|
while (cur)
|
|
{
|
|
tmp = cur;
|
|
cur = (struct lto_char_ptr_base *) cur->ptr;
|
|
free (tmp);
|
|
}
|
|
|
|
/* Free any sections and their data chains. */
|
|
for (i = 0;
|
|
VEC_iterate (lto_mach_o_section, mach_o_file->section_vec, i, sec);
|
|
i++)
|
|
{
|
|
lto_mach_o_data curdata, nextdata;
|
|
curdata = sec->data_chain;
|
|
while (curdata)
|
|
{
|
|
nextdata = curdata->next;
|
|
free (curdata);
|
|
curdata = nextdata;
|
|
}
|
|
free (sec);
|
|
}
|
|
VEC_free (lto_mach_o_section, heap, mach_o_file->section_vec);
|
|
|
|
free (file);
|
|
|
|
/* If there was an error, mention it. */
|
|
if (write_err)
|
|
error ("I/O error writing Mach-O output file");
|
|
}
|
|
|