964 lines
24 KiB
C
964 lines
24 KiB
C
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/* SEC_MERGE support.
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Copyright (C) 2001-2022 Free Software Foundation, Inc.
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Written by Jakub Jelinek <jakub@redhat.com>.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License 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 this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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/* This file contains support for merging duplicate entities within sections,
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as used in ELF SHF_MERGE. */
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#include "sysdep.h"
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#include <limits.h>
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#include "bfd.h"
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#include "elf-bfd.h"
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#include "libbfd.h"
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#include "hashtab.h"
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#include "libiberty.h"
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struct sec_merge_sec_info;
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/* An entry in the section merge hash table. */
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struct sec_merge_hash_entry
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{
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struct bfd_hash_entry root;
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/* Length of this entry. This includes the zero terminator. */
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unsigned int len;
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/* Start of this string needs to be aligned to
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alignment octets (not 1 << align). */
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unsigned int alignment;
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union
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{
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/* Index within the merged section. */
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bfd_size_type index;
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/* Entry this is a suffix of (if alignment is 0). */
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struct sec_merge_hash_entry *suffix;
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} u;
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/* Which section is it in. */
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struct sec_merge_sec_info *secinfo;
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/* Next entity in the hash table. */
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struct sec_merge_hash_entry *next;
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};
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/* The section merge hash table. */
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struct sec_merge_hash
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{
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struct bfd_hash_table table;
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/* Next available index. */
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bfd_size_type size;
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/* First entity in the SEC_MERGE sections of this type. */
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struct sec_merge_hash_entry *first;
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/* Last entity in the SEC_MERGE sections of this type. */
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struct sec_merge_hash_entry *last;
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/* Entity size. */
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unsigned int entsize;
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/* Are entries fixed size or zero terminated strings? */
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bool strings;
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};
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struct sec_merge_info
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{
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/* Chain of sec_merge_infos. */
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struct sec_merge_info *next;
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/* Chain of sec_merge_sec_infos. */
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struct sec_merge_sec_info *chain;
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/* A hash table used to hold section content. */
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struct sec_merge_hash *htab;
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};
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struct sec_merge_sec_info
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{
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/* Chain of sec_merge_sec_infos. */
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struct sec_merge_sec_info *next;
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/* The corresponding section. */
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asection *sec;
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/* Pointer to merge_info pointing to us. */
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void **psecinfo;
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/* A hash table used to hold section content. */
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struct sec_merge_hash *htab;
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/* First string in this section. */
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struct sec_merge_hash_entry *first_str;
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/* Original section content. */
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unsigned char contents[1];
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};
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/* Routine to create an entry in a section merge hashtab. */
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static struct bfd_hash_entry *
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sec_merge_hash_newfunc (struct bfd_hash_entry *entry,
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struct bfd_hash_table *table, const char *string)
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{
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/* Allocate the structure if it has not already been allocated by a
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subclass. */
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if (entry == NULL)
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entry = (struct bfd_hash_entry *)
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bfd_hash_allocate (table, sizeof (struct sec_merge_hash_entry));
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if (entry == NULL)
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return NULL;
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/* Call the allocation method of the superclass. */
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entry = bfd_hash_newfunc (entry, table, string);
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if (entry != NULL)
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{
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/* Initialize the local fields. */
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struct sec_merge_hash_entry *ret = (struct sec_merge_hash_entry *) entry;
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ret->u.suffix = NULL;
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ret->alignment = 0;
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ret->secinfo = NULL;
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ret->next = NULL;
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}
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return entry;
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}
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/* Look up an entry in a section merge hash table. */
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static struct sec_merge_hash_entry *
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sec_merge_hash_lookup (struct sec_merge_hash *table, const char *string,
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unsigned int alignment, bool create)
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{
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const unsigned char *s;
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unsigned long hash;
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unsigned int c;
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struct sec_merge_hash_entry *hashp;
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unsigned int len, i;
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unsigned int _index;
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hash = 0;
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len = 0;
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s = (const unsigned char *) string;
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if (table->strings)
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{
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if (table->entsize == 1)
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{
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while ((c = *s++) != '\0')
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{
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hash += c + (c << 17);
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hash ^= hash >> 2;
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++len;
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}
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hash += len + (len << 17);
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}
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else
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{
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for (;;)
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{
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for (i = 0; i < table->entsize; ++i)
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if (s[i] != '\0')
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break;
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if (i == table->entsize)
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break;
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for (i = 0; i < table->entsize; ++i)
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{
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c = *s++;
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hash += c + (c << 17);
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hash ^= hash >> 2;
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}
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++len;
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}
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hash += len + (len << 17);
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len *= table->entsize;
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}
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hash ^= hash >> 2;
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len += table->entsize;
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}
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else
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{
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for (i = 0; i < table->entsize; ++i)
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{
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c = *s++;
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hash += c + (c << 17);
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hash ^= hash >> 2;
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}
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len = table->entsize;
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}
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_index = hash % table->table.size;
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for (hashp = (struct sec_merge_hash_entry *) table->table.table[_index];
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hashp != NULL;
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hashp = (struct sec_merge_hash_entry *) hashp->root.next)
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{
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if (hashp->root.hash == hash
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&& len == hashp->len
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&& memcmp (hashp->root.string, string, len) == 0)
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{
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/* If the string we found does not have at least the required
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alignment, we need to insert another copy. */
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if (hashp->alignment < alignment)
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{
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if (create)
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{
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/* Mark the less aligned copy as deleted. */
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hashp->len = 0;
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hashp->alignment = 0;
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}
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break;
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}
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return hashp;
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}
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}
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if (! create)
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return NULL;
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hashp = ((struct sec_merge_hash_entry *)
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bfd_hash_insert (&table->table, string, hash));
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if (hashp == NULL)
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return NULL;
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hashp->len = len;
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hashp->alignment = alignment;
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return hashp;
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}
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/* Create a new hash table. */
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static struct sec_merge_hash *
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sec_merge_init (unsigned int entsize, bool strings)
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{
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struct sec_merge_hash *table;
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table = (struct sec_merge_hash *) bfd_malloc (sizeof (struct sec_merge_hash));
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if (table == NULL)
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return NULL;
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if (! bfd_hash_table_init_n (&table->table, sec_merge_hash_newfunc,
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sizeof (struct sec_merge_hash_entry), 16699))
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{
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free (table);
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return NULL;
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}
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table->size = 0;
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table->first = NULL;
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table->last = NULL;
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table->entsize = entsize;
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table->strings = strings;
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return table;
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}
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/* Get the index of an entity in a hash table, adding it if it is not
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already present. */
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static struct sec_merge_hash_entry *
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sec_merge_add (struct sec_merge_hash *tab, const char *str,
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unsigned int alignment, struct sec_merge_sec_info *secinfo)
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{
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struct sec_merge_hash_entry *entry;
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entry = sec_merge_hash_lookup (tab, str, alignment, true);
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if (entry == NULL)
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return NULL;
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if (entry->secinfo == NULL)
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{
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tab->size++;
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entry->secinfo = secinfo;
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if (tab->first == NULL)
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tab->first = entry;
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else
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tab->last->next = entry;
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tab->last = entry;
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}
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return entry;
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}
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static bool
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sec_merge_emit (bfd *abfd, struct sec_merge_hash_entry *entry,
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unsigned char *contents, file_ptr offset)
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{
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struct sec_merge_sec_info *secinfo = entry->secinfo;
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asection *sec = secinfo->sec;
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char *pad = NULL;
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bfd_size_type off = 0;
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unsigned int opb = bfd_octets_per_byte (abfd, sec);
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int alignment_power = sec->output_section->alignment_power * opb;
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bfd_size_type pad_len; /* Octets. */
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/* FIXME: If alignment_power is 0 then really we should scan the
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entry list for the largest required alignment and use that. */
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pad_len = alignment_power ? ((bfd_size_type) 1 << alignment_power) : 16;
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pad = (char *) bfd_zmalloc (pad_len);
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if (pad == NULL)
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return false;
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for (; entry != NULL && entry->secinfo == secinfo; entry = entry->next)
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{
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const char *str;
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bfd_size_type len;
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||
|
|
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len = -off & (entry->alignment - 1);
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if (len != 0)
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{
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BFD_ASSERT (len <= pad_len);
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if (contents)
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{
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memcpy (contents + offset, pad, len);
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offset += len;
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|
}
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else if (bfd_bwrite (pad, len, abfd) != len)
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||
|
goto err;
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|
off += len;
|
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|
}
|
||
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|
||
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str = entry->root.string;
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||
|
len = entry->len;
|
||
|
|
||
|
if (contents)
|
||
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{
|
||
|
memcpy (contents + offset, str, len);
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offset += len;
|
||
|
}
|
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|
else if (bfd_bwrite (str, len, abfd) != len)
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||
|
goto err;
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||
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off += len;
|
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|
}
|
||
|
|
||
|
/* Trailing alignment needed? */
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||
|
off = sec->size - off;
|
||
|
if (off != 0)
|
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{
|
||
|
BFD_ASSERT (off <= pad_len);
|
||
|
if (contents)
|
||
|
memcpy (contents + offset, pad, off);
|
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|
else if (bfd_bwrite (pad, off, abfd) != off)
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||
|
goto err;
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|
}
|
||
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|
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free (pad);
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return true;
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||
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||
|
err:
|
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|
free (pad);
|
||
|
return false;
|
||
|
}
|
||
|
|
||
|
/* Register a SEC_MERGE section as a candidate for merging.
|
||
|
This function is called for all non-dynamic SEC_MERGE input sections. */
|
||
|
|
||
|
bool
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||
|
_bfd_add_merge_section (bfd *abfd, void **psinfo, asection *sec,
|
||
|
void **psecinfo)
|
||
|
{
|
||
|
struct sec_merge_info *sinfo;
|
||
|
struct sec_merge_sec_info *secinfo;
|
||
|
unsigned int alignment_power; /* Octets. */
|
||
|
unsigned int align; /* Octets. */
|
||
|
bfd_size_type amt;
|
||
|
bfd_byte *contents;
|
||
|
unsigned int opb = bfd_octets_per_byte (abfd, sec);
|
||
|
|
||
|
if ((abfd->flags & DYNAMIC) != 0
|
||
|
|| (sec->flags & SEC_MERGE) == 0)
|
||
|
abort ();
|
||
|
|
||
|
if (sec->size == 0
|
||
|
|| (sec->flags & SEC_EXCLUDE) != 0
|
||
|
|| sec->entsize == 0)
|
||
|
return true;
|
||
|
|
||
|
if (sec->size % sec->entsize != 0)
|
||
|
return true;
|
||
|
|
||
|
if ((sec->flags & SEC_RELOC) != 0)
|
||
|
{
|
||
|
/* We aren't prepared to handle relocations in merged sections. */
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
#ifndef CHAR_BIT
|
||
|
#define CHAR_BIT 8
|
||
|
#endif
|
||
|
alignment_power = sec->alignment_power * opb;
|
||
|
if (alignment_power >= sizeof (align) * CHAR_BIT)
|
||
|
return true;
|
||
|
|
||
|
align = 1u << alignment_power;
|
||
|
if ((sec->entsize < align
|
||
|
&& ((sec->entsize & (sec->entsize - 1))
|
||
|
|| !(sec->flags & SEC_STRINGS)))
|
||
|
|| (sec->entsize > align
|
||
|
&& (sec->entsize & (align - 1))))
|
||
|
{
|
||
|
/* Sanity check. If string character size is smaller than
|
||
|
alignment, then we require character size to be a power
|
||
|
of 2, otherwise character size must be integer multiple
|
||
|
of alignment. For non-string constants, alignment must
|
||
|
be smaller than or equal to entity size and entity size
|
||
|
must be integer multiple of alignment. */
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
for (sinfo = (struct sec_merge_info *) *psinfo; sinfo; sinfo = sinfo->next)
|
||
|
if ((secinfo = sinfo->chain)
|
||
|
&& ! ((secinfo->sec->flags ^ sec->flags) & (SEC_MERGE | SEC_STRINGS))
|
||
|
&& secinfo->sec->entsize == sec->entsize
|
||
|
&& secinfo->sec->alignment_power == sec->alignment_power
|
||
|
&& secinfo->sec->output_section == sec->output_section)
|
||
|
break;
|
||
|
|
||
|
if (sinfo == NULL)
|
||
|
{
|
||
|
/* Initialize the information we need to keep track of. */
|
||
|
sinfo = (struct sec_merge_info *)
|
||
|
bfd_alloc (abfd, sizeof (struct sec_merge_info));
|
||
|
if (sinfo == NULL)
|
||
|
goto error_return;
|
||
|
sinfo->next = (struct sec_merge_info *) *psinfo;
|
||
|
sinfo->chain = NULL;
|
||
|
*psinfo = sinfo;
|
||
|
sinfo->htab = sec_merge_init (sec->entsize, (sec->flags & SEC_STRINGS));
|
||
|
if (sinfo->htab == NULL)
|
||
|
goto error_return;
|
||
|
}
|
||
|
|
||
|
/* Read the section from abfd. */
|
||
|
|
||
|
amt = sizeof (struct sec_merge_sec_info) - 1 + sec->size;
|
||
|
if (sec->flags & SEC_STRINGS)
|
||
|
/* Some versions of gcc may emit a string without a zero terminator.
|
||
|
See http://gcc.gnu.org/ml/gcc-patches/2006-06/msg01004.html
|
||
|
Allocate space for an extra zero. */
|
||
|
amt += sec->entsize;
|
||
|
*psecinfo = bfd_alloc (abfd, amt);
|
||
|
if (*psecinfo == NULL)
|
||
|
goto error_return;
|
||
|
|
||
|
secinfo = (struct sec_merge_sec_info *) *psecinfo;
|
||
|
if (sinfo->chain)
|
||
|
{
|
||
|
secinfo->next = sinfo->chain->next;
|
||
|
sinfo->chain->next = secinfo;
|
||
|
}
|
||
|
else
|
||
|
secinfo->next = secinfo;
|
||
|
sinfo->chain = secinfo;
|
||
|
secinfo->sec = sec;
|
||
|
secinfo->psecinfo = psecinfo;
|
||
|
secinfo->htab = sinfo->htab;
|
||
|
secinfo->first_str = NULL;
|
||
|
|
||
|
sec->rawsize = sec->size;
|
||
|
if (sec->flags & SEC_STRINGS)
|
||
|
memset (secinfo->contents + sec->size, 0, sec->entsize);
|
||
|
contents = secinfo->contents;
|
||
|
if (! bfd_get_full_section_contents (sec->owner, sec, &contents))
|
||
|
goto error_return;
|
||
|
|
||
|
return true;
|
||
|
|
||
|
error_return:
|
||
|
*psecinfo = NULL;
|
||
|
return false;
|
||
|
}
|
||
|
|
||
|
/* Record one section into the hash table. */
|
||
|
static bool
|
||
|
record_section (struct sec_merge_info *sinfo,
|
||
|
struct sec_merge_sec_info *secinfo)
|
||
|
{
|
||
|
asection *sec = secinfo->sec;
|
||
|
struct sec_merge_hash_entry *entry;
|
||
|
bool nul;
|
||
|
unsigned char *p, *end;
|
||
|
bfd_vma mask, eltalign;
|
||
|
unsigned int align, i;
|
||
|
|
||
|
align = sec->alignment_power;
|
||
|
end = secinfo->contents + sec->size;
|
||
|
nul = false;
|
||
|
mask = ((bfd_vma) 1 << align) - 1;
|
||
|
if (sec->flags & SEC_STRINGS)
|
||
|
{
|
||
|
for (p = secinfo->contents; p < end; )
|
||
|
{
|
||
|
eltalign = p - secinfo->contents;
|
||
|
eltalign = ((eltalign ^ (eltalign - 1)) + 1) >> 1;
|
||
|
if (!eltalign || eltalign > mask)
|
||
|
eltalign = mask + 1;
|
||
|
entry = sec_merge_add (sinfo->htab, (char *) p, (unsigned) eltalign,
|
||
|
secinfo);
|
||
|
if (! entry)
|
||
|
goto error_return;
|
||
|
p += entry->len;
|
||
|
if (sec->entsize == 1)
|
||
|
{
|
||
|
while (p < end && *p == 0)
|
||
|
{
|
||
|
if (!nul && !((p - secinfo->contents) & mask))
|
||
|
{
|
||
|
nul = true;
|
||
|
entry = sec_merge_add (sinfo->htab, "",
|
||
|
(unsigned) mask + 1, secinfo);
|
||
|
if (! entry)
|
||
|
goto error_return;
|
||
|
}
|
||
|
p++;
|
||
|
}
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
while (p < end)
|
||
|
{
|
||
|
for (i = 0; i < sec->entsize; i++)
|
||
|
if (p[i] != '\0')
|
||
|
break;
|
||
|
if (i != sec->entsize)
|
||
|
break;
|
||
|
if (!nul && !((p - secinfo->contents) & mask))
|
||
|
{
|
||
|
nul = true;
|
||
|
entry = sec_merge_add (sinfo->htab, (char *) p,
|
||
|
(unsigned) mask + 1, secinfo);
|
||
|
if (! entry)
|
||
|
goto error_return;
|
||
|
}
|
||
|
p += sec->entsize;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
for (p = secinfo->contents; p < end; p += sec->entsize)
|
||
|
{
|
||
|
entry = sec_merge_add (sinfo->htab, (char *) p, 1, secinfo);
|
||
|
if (! entry)
|
||
|
goto error_return;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return true;
|
||
|
|
||
|
error_return:
|
||
|
for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next)
|
||
|
*secinfo->psecinfo = NULL;
|
||
|
return false;
|
||
|
}
|
||
|
|
||
|
/* qsort comparison function. Won't ever return zero as all entries
|
||
|
differ, so there is no issue with qsort stability here. */
|
||
|
|
||
|
static int
|
||
|
strrevcmp (const void *a, const void *b)
|
||
|
{
|
||
|
struct sec_merge_hash_entry *A = *(struct sec_merge_hash_entry **) a;
|
||
|
struct sec_merge_hash_entry *B = *(struct sec_merge_hash_entry **) b;
|
||
|
unsigned int lenA = A->len;
|
||
|
unsigned int lenB = B->len;
|
||
|
const unsigned char *s = (const unsigned char *) A->root.string + lenA - 1;
|
||
|
const unsigned char *t = (const unsigned char *) B->root.string + lenB - 1;
|
||
|
int l = lenA < lenB ? lenA : lenB;
|
||
|
|
||
|
while (l)
|
||
|
{
|
||
|
if (*s != *t)
|
||
|
return (int) *s - (int) *t;
|
||
|
s--;
|
||
|
t--;
|
||
|
l--;
|
||
|
}
|
||
|
return lenA - lenB;
|
||
|
}
|
||
|
|
||
|
/* Like strrevcmp, but for the case where all strings have the same
|
||
|
alignment > entsize. */
|
||
|
|
||
|
static int
|
||
|
strrevcmp_align (const void *a, const void *b)
|
||
|
{
|
||
|
struct sec_merge_hash_entry *A = *(struct sec_merge_hash_entry **) a;
|
||
|
struct sec_merge_hash_entry *B = *(struct sec_merge_hash_entry **) b;
|
||
|
unsigned int lenA = A->len;
|
||
|
unsigned int lenB = B->len;
|
||
|
const unsigned char *s = (const unsigned char *) A->root.string + lenA - 1;
|
||
|
const unsigned char *t = (const unsigned char *) B->root.string + lenB - 1;
|
||
|
int l = lenA < lenB ? lenA : lenB;
|
||
|
int tail_align = (lenA & (A->alignment - 1)) - (lenB & (A->alignment - 1));
|
||
|
|
||
|
if (tail_align != 0)
|
||
|
return tail_align;
|
||
|
|
||
|
while (l)
|
||
|
{
|
||
|
if (*s != *t)
|
||
|
return (int) *s - (int) *t;
|
||
|
s--;
|
||
|
t--;
|
||
|
l--;
|
||
|
}
|
||
|
return lenA - lenB;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
is_suffix (const struct sec_merge_hash_entry *A,
|
||
|
const struct sec_merge_hash_entry *B)
|
||
|
{
|
||
|
if (A->len <= B->len)
|
||
|
/* B cannot be a suffix of A unless A is equal to B, which is guaranteed
|
||
|
not to be equal by the hash table. */
|
||
|
return 0;
|
||
|
|
||
|
return memcmp (A->root.string + (A->len - B->len),
|
||
|
B->root.string, B->len) == 0;
|
||
|
}
|
||
|
|
||
|
/* This is a helper function for _bfd_merge_sections. It attempts to
|
||
|
merge strings matching suffixes of longer strings. */
|
||
|
static struct sec_merge_sec_info *
|
||
|
merge_strings (struct sec_merge_info *sinfo)
|
||
|
{
|
||
|
struct sec_merge_hash_entry **array, **a, *e;
|
||
|
struct sec_merge_sec_info *secinfo;
|
||
|
bfd_size_type size, amt;
|
||
|
unsigned int alignment = 0;
|
||
|
|
||
|
/* Now sort the strings */
|
||
|
amt = sinfo->htab->size * sizeof (struct sec_merge_hash_entry *);
|
||
|
array = (struct sec_merge_hash_entry **) bfd_malloc (amt);
|
||
|
if (array == NULL)
|
||
|
return NULL;
|
||
|
|
||
|
for (e = sinfo->htab->first, a = array; e; e = e->next)
|
||
|
if (e->alignment)
|
||
|
{
|
||
|
*a++ = e;
|
||
|
/* Adjust the length to not include the zero terminator. */
|
||
|
e->len -= sinfo->htab->entsize;
|
||
|
if (alignment != e->alignment)
|
||
|
{
|
||
|
if (alignment == 0)
|
||
|
alignment = e->alignment;
|
||
|
else
|
||
|
alignment = (unsigned) -1;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
sinfo->htab->size = a - array;
|
||
|
if (sinfo->htab->size != 0)
|
||
|
{
|
||
|
qsort (array, (size_t) sinfo->htab->size,
|
||
|
sizeof (struct sec_merge_hash_entry *),
|
||
|
(alignment != (unsigned) -1 && alignment > sinfo->htab->entsize
|
||
|
? strrevcmp_align : strrevcmp));
|
||
|
|
||
|
/* Loop over the sorted array and merge suffixes */
|
||
|
e = *--a;
|
||
|
e->len += sinfo->htab->entsize;
|
||
|
while (--a >= array)
|
||
|
{
|
||
|
struct sec_merge_hash_entry *cmp = *a;
|
||
|
|
||
|
cmp->len += sinfo->htab->entsize;
|
||
|
if (e->alignment >= cmp->alignment
|
||
|
&& !((e->len - cmp->len) & (cmp->alignment - 1))
|
||
|
&& is_suffix (e, cmp))
|
||
|
{
|
||
|
cmp->u.suffix = e;
|
||
|
cmp->alignment = 0;
|
||
|
}
|
||
|
else
|
||
|
e = cmp;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
free (array);
|
||
|
|
||
|
/* Now assign positions to the strings we want to keep. */
|
||
|
size = 0;
|
||
|
secinfo = sinfo->htab->first->secinfo;
|
||
|
for (e = sinfo->htab->first; e; e = e->next)
|
||
|
{
|
||
|
if (e->secinfo != secinfo)
|
||
|
{
|
||
|
secinfo->sec->size = size;
|
||
|
secinfo = e->secinfo;
|
||
|
}
|
||
|
if (e->alignment)
|
||
|
{
|
||
|
if (e->secinfo->first_str == NULL)
|
||
|
{
|
||
|
e->secinfo->first_str = e;
|
||
|
size = 0;
|
||
|
}
|
||
|
size = (size + e->alignment - 1) & ~((bfd_vma) e->alignment - 1);
|
||
|
e->u.index = size;
|
||
|
size += e->len;
|
||
|
}
|
||
|
}
|
||
|
secinfo->sec->size = size;
|
||
|
|
||
|
/* And now adjust the rest, removing them from the chain (but not hashtable)
|
||
|
at the same time. */
|
||
|
for (a = &sinfo->htab->first, e = *a; e; e = e->next)
|
||
|
if (e->alignment)
|
||
|
a = &e->next;
|
||
|
else
|
||
|
{
|
||
|
*a = e->next;
|
||
|
if (e->len)
|
||
|
{
|
||
|
e->secinfo = e->u.suffix->secinfo;
|
||
|
e->alignment = e->u.suffix->alignment;
|
||
|
e->u.index = e->u.suffix->u.index + (e->u.suffix->len - e->len);
|
||
|
}
|
||
|
}
|
||
|
return secinfo;
|
||
|
}
|
||
|
|
||
|
/* This function is called once after all SEC_MERGE sections are registered
|
||
|
with _bfd_merge_section. */
|
||
|
|
||
|
bool
|
||
|
_bfd_merge_sections (bfd *abfd,
|
||
|
struct bfd_link_info *info ATTRIBUTE_UNUSED,
|
||
|
void *xsinfo,
|
||
|
void (*remove_hook) (bfd *, asection *))
|
||
|
{
|
||
|
struct sec_merge_info *sinfo;
|
||
|
|
||
|
for (sinfo = (struct sec_merge_info *) xsinfo; sinfo; sinfo = sinfo->next)
|
||
|
{
|
||
|
struct sec_merge_sec_info *secinfo;
|
||
|
bfd_size_type align; /* Bytes. */
|
||
|
|
||
|
if (! sinfo->chain)
|
||
|
continue;
|
||
|
|
||
|
/* Move sinfo->chain to head of the chain, terminate it. */
|
||
|
secinfo = sinfo->chain;
|
||
|
sinfo->chain = secinfo->next;
|
||
|
secinfo->next = NULL;
|
||
|
|
||
|
/* Record the sections into the hash table. */
|
||
|
align = 1;
|
||
|
for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next)
|
||
|
if (secinfo->sec->flags & SEC_EXCLUDE)
|
||
|
{
|
||
|
*secinfo->psecinfo = NULL;
|
||
|
if (remove_hook)
|
||
|
(*remove_hook) (abfd, secinfo->sec);
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
if (!record_section (sinfo, secinfo))
|
||
|
return false;
|
||
|
if (align)
|
||
|
{
|
||
|
unsigned int opb = bfd_octets_per_byte (abfd, secinfo->sec);
|
||
|
|
||
|
align = (bfd_size_type) 1 << secinfo->sec->alignment_power;
|
||
|
if (((secinfo->sec->size / opb) & (align - 1)) != 0)
|
||
|
align = 0;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (sinfo->htab->first == NULL)
|
||
|
continue;
|
||
|
|
||
|
if (sinfo->htab->strings)
|
||
|
{
|
||
|
secinfo = merge_strings (sinfo);
|
||
|
if (!secinfo)
|
||
|
return false;
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
struct sec_merge_hash_entry *e;
|
||
|
bfd_size_type size = 0; /* Octets. */
|
||
|
|
||
|
/* Things are much simpler for non-strings.
|
||
|
Just assign them slots in the section. */
|
||
|
secinfo = NULL;
|
||
|
for (e = sinfo->htab->first; e; e = e->next)
|
||
|
{
|
||
|
if (e->secinfo->first_str == NULL)
|
||
|
{
|
||
|
if (secinfo)
|
||
|
secinfo->sec->size = size;
|
||
|
e->secinfo->first_str = e;
|
||
|
size = 0;
|
||
|
}
|
||
|
size = (size + e->alignment - 1) & ~((bfd_vma) e->alignment - 1);
|
||
|
e->u.index = size;
|
||
|
size += e->len;
|
||
|
secinfo = e->secinfo;
|
||
|
}
|
||
|
secinfo->sec->size = size;
|
||
|
}
|
||
|
|
||
|
/* If the input sections were padded according to their alignments,
|
||
|
then pad the output too. */
|
||
|
if (align)
|
||
|
secinfo->sec->size = (secinfo->sec->size + align - 1) & -align;
|
||
|
|
||
|
/* Finally remove all input sections which have not made it into
|
||
|
the hash table at all. */
|
||
|
for (secinfo = sinfo->chain; secinfo; secinfo = secinfo->next)
|
||
|
if (secinfo->first_str == NULL)
|
||
|
secinfo->sec->flags |= SEC_EXCLUDE | SEC_KEEP;
|
||
|
}
|
||
|
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
/* Write out the merged section. */
|
||
|
|
||
|
bool
|
||
|
_bfd_write_merged_section (bfd *output_bfd, asection *sec, void *psecinfo)
|
||
|
{
|
||
|
struct sec_merge_sec_info *secinfo;
|
||
|
file_ptr pos;
|
||
|
unsigned char *contents;
|
||
|
Elf_Internal_Shdr *hdr;
|
||
|
|
||
|
secinfo = (struct sec_merge_sec_info *) psecinfo;
|
||
|
|
||
|
if (!secinfo)
|
||
|
return false;
|
||
|
|
||
|
if (secinfo->first_str == NULL)
|
||
|
return true;
|
||
|
|
||
|
/* FIXME: octets_per_byte. */
|
||
|
hdr = &elf_section_data (sec->output_section)->this_hdr;
|
||
|
if (hdr->sh_offset == (file_ptr) -1)
|
||
|
{
|
||
|
/* We must compress this section. Write output to the
|
||
|
buffer. */
|
||
|
contents = hdr->contents;
|
||
|
if ((sec->output_section->flags & SEC_ELF_COMPRESS) == 0
|
||
|
|| contents == NULL)
|
||
|
abort ();
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
contents = NULL;
|
||
|
pos = sec->output_section->filepos + sec->output_offset;
|
||
|
if (bfd_seek (output_bfd, pos, SEEK_SET) != 0)
|
||
|
return false;
|
||
|
}
|
||
|
|
||
|
if (! sec_merge_emit (output_bfd, secinfo->first_str, contents,
|
||
|
sec->output_offset))
|
||
|
return false;
|
||
|
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
/* Adjust an address in the SEC_MERGE section. Given OFFSET within
|
||
|
*PSEC, this returns the new offset in the adjusted SEC_MERGE
|
||
|
section and writes the new section back into *PSEC. */
|
||
|
|
||
|
bfd_vma
|
||
|
_bfd_merged_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED, asection **psec,
|
||
|
void *psecinfo, bfd_vma offset)
|
||
|
{
|
||
|
struct sec_merge_sec_info *secinfo;
|
||
|
struct sec_merge_hash_entry *entry;
|
||
|
unsigned char *p;
|
||
|
asection *sec = *psec;
|
||
|
|
||
|
secinfo = (struct sec_merge_sec_info *) psecinfo;
|
||
|
|
||
|
if (!secinfo)
|
||
|
return offset;
|
||
|
|
||
|
if (offset >= sec->rawsize)
|
||
|
{
|
||
|
if (offset > sec->rawsize)
|
||
|
_bfd_error_handler
|
||
|
/* xgettext:c-format */
|
||
|
(_("%pB: access beyond end of merged section (%" PRId64 ")"),
|
||
|
sec->owner, (int64_t) offset);
|
||
|
return secinfo->first_str ? sec->size : 0;
|
||
|
}
|
||
|
|
||
|
if (secinfo->htab->strings)
|
||
|
{
|
||
|
if (sec->entsize == 1)
|
||
|
{
|
||
|
p = secinfo->contents + offset - 1;
|
||
|
while (p >= secinfo->contents && *p)
|
||
|
--p;
|
||
|
++p;
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
p = secinfo->contents + (offset / sec->entsize) * sec->entsize;
|
||
|
p -= sec->entsize;
|
||
|
while (p >= secinfo->contents)
|
||
|
{
|
||
|
unsigned int i;
|
||
|
|
||
|
for (i = 0; i < sec->entsize; ++i)
|
||
|
if (p[i] != '\0')
|
||
|
break;
|
||
|
if (i == sec->entsize)
|
||
|
break;
|
||
|
p -= sec->entsize;
|
||
|
}
|
||
|
p += sec->entsize;
|
||
|
}
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
p = secinfo->contents + (offset / sec->entsize) * sec->entsize;
|
||
|
}
|
||
|
entry = sec_merge_hash_lookup (secinfo->htab, (char *) p, 0, false);
|
||
|
if (!entry)
|
||
|
{
|
||
|
if (! secinfo->htab->strings)
|
||
|
abort ();
|
||
|
/* This should only happen if somebody points into the padding
|
||
|
after a NUL character but before next entity. */
|
||
|
if (*p)
|
||
|
abort ();
|
||
|
if (! secinfo->htab->first)
|
||
|
abort ();
|
||
|
entry = secinfo->htab->first;
|
||
|
p = (secinfo->contents + (offset / sec->entsize + 1) * sec->entsize
|
||
|
- entry->len);
|
||
|
}
|
||
|
|
||
|
*psec = entry->secinfo->sec;
|
||
|
return entry->u.index + (secinfo->contents + offset - p);
|
||
|
}
|
||
|
|
||
|
/* Tidy up when done. */
|
||
|
|
||
|
void
|
||
|
_bfd_merge_sections_free (void *xsinfo)
|
||
|
{
|
||
|
struct sec_merge_info *sinfo;
|
||
|
|
||
|
for (sinfo = (struct sec_merge_info *) xsinfo; sinfo; sinfo = sinfo->next)
|
||
|
{
|
||
|
bfd_hash_table_free (&sinfo->htab->table);
|
||
|
free (sinfo->htab);
|
||
|
}
|
||
|
}
|