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/* Copyright (C) 1991 Free Software Foundation, Inc.
This file is part of GLD, the Gnu Linker.
GLD 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 1, or (at your option)
any later version.
GLD 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 GLD; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
/*
* $Id$
*
*
*/
/*
Written by Steve Chamberlain steve@cygnus.com
All symbol handling for the linker
*/
#include "sysdep.h"
#include "bfd.h"
#include "ld.h"
#include "ldsym.h"
#include "ldmisc.h"
#include "ldlang.h"
/* IMPORT */
extern bfd *output_bfd;
extern strip_symbols_type strip_symbols;
extern discard_locals_type discard_locals;
/* Head and tail of global symbol table chronological list */
ldsym_type *symbol_head = (ldsym_type *)NULL;
ldsym_type **symbol_tail_ptr = &symbol_head;
/*
incremented for each symbol in the ldsym_type table
no matter what flavour it is
*/
unsigned int global_symbol_count;
/* IMPORTS */
extern boolean option_longmap ;
/* LOCALS */
#define TABSIZE 1009
static ldsym_type *global_symbol_hash_table[TABSIZE];
/* Compute the hash code for symbol name KEY. */
int
hash_string (key)
char *key;
{
register char *cp;
register int k;
cp = key;
k = 0;
while (*cp)
k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
return k;
}
/* Get the symbol table entry for the global symbol named KEY.
Create one if there is none. */
ldsym_type *
DEFUN(ldsym_get,(key),
CONST char *key)
{
register int hashval;
register ldsym_type *bp;
/* Determine the proper bucket. */
hashval = hash_string (key) % TABSIZE;
/* Search the bucket. */
for (bp = global_symbol_hash_table[hashval]; bp; bp = bp->link)
if (! strcmp (key, bp->name))
return bp;
/* Nothing was found; create a new symbol table entry. */
bp = (ldsym_type *) ldmalloc (sizeof (ldsym_type));
bp->srefs_chain = (asymbol **)NULL;
bp->sdefs_chain = (asymbol **)NULL;
bp->scoms_chain = (asymbol **)NULL;
bp->name = buystring(key);
/* Add the entry to the bucket. */
bp->link = global_symbol_hash_table[hashval];
global_symbol_hash_table[hashval] = bp;
/* Keep the chronological list up to date too */
*symbol_tail_ptr = bp;
symbol_tail_ptr = &bp->next;
bp->next = 0;
global_symbol_count++;
return bp;
}
/* Like `ldsym_get' but return 0 if the symbol is not already known. */
ldsym_type *
DEFUN(ldsym_get_soft,(key),
CONST char *key)
{
register int hashval;
register ldsym_type *bp;
/* Determine which bucket. */
hashval = hash_string (key) % TABSIZE;
/* Search the bucket. */
for (bp = global_symbol_hash_table[hashval]; bp; bp = bp->link)
if (! strcmp (key, bp->name))
return bp;
return 0;
}
static void
list_file_locals (entry)
lang_input_statement_type *entry;
{
asymbol **q;
fprintf (stderr, "\nLocal symbols of ");
info("%I", entry);
fprintf (stderr, ":\n\n");
if (entry->asymbols) {
for (q = entry->asymbols; *q; q++)
{
asymbol *p = *q;
/* If this is a definition,
update it if necessary by this file's start address. */
if (p->flags & BSF_LOCAL)
info(" %V %s\n",p->value, p->name);
}
}
}
static void
print_file_stuff(f)
lang_input_statement_type *f;
{
fprintf (stderr, " %s", f->filename);
fprintf (stderr, " ");
if (f->just_syms_flag)
{
fprintf (stderr, " symbols only\n");
}
else
{
asection *s;
if (option_longmap) {
for (s = f->the_bfd->sections;
s != (asection *)NULL;
s = s->next) {
fprintf (stderr, "%08lx %08x 2**%2ud %s\n",
s->output_offset,
(unsigned)s->size, s->alignment_power, s->name);
}
}
else {
for (s = f->the_bfd->sections;
s != (asection *)NULL;
s = s->next) {
fprintf (stderr, "%s %lx(%x) ",
s->name,
s->output_offset,
(unsigned) s->size);
}
fprintf (stderr, "hex \n");
}
}
}
void
ldsym_print_symbol_table ()
{
fprintf (stderr, "\nFiles:\n\n");
lang_for_each_file(print_file_stuff);
fprintf (stderr, "\nGlobal symbols:\n\n");
{
register ldsym_type *sp;
for (sp = symbol_head; sp; sp = sp->next)
{
if (sp->sdefs_chain)
{
asymbol *defsym = *(sp->sdefs_chain);
asection *defsec = bfd_get_section(defsym);
fprintf(stderr,"%08lx ",defsym->value);
if (defsec)
{
fprintf(stderr,"%08lx ",defsym->value+defsec->vma);
fprintf(stderr,
"%7s",
bfd_section_name(output_bfd,
defsec));
}
else
{
fprintf(stderr," .......");
}
}
else {
fprintf(stderr,"undefined");
}
if (sp->scoms_chain) {
fprintf(stderr, " common size %5lu %s",
(*(sp->scoms_chain))->value, sp->name);
}
if (sp->sdefs_chain) {
fprintf(stderr, " symbol def %08lx %s",
(*(sp->sdefs_chain))->value,
sp->name);
}
else {
fprintf(stderr, " undefined %s",
sp->name);
}
fprintf(stderr, "\n");
}
}
lang_for_each_file(list_file_locals);
}
extern lang_output_section_statement_type *create_object_symbols;
extern char lprefix;
static asymbol **
write_file_locals(output_buffer)
asymbol **output_buffer;
{
LANG_FOR_EACH_INPUT_STATEMENT(entry)
{
/* Run trough the symbols and work out what to do with them */
unsigned int i;
/* Add one for the filename symbol if needed */
if (create_object_symbols
!= (lang_output_section_statement_type *)NULL) {
asection *s;
for (s = entry->the_bfd->sections;
s != (asection *)NULL;
s = s->next) {
if (s->output_section == create_object_symbols->bfd_section) {
/* Add symbol to this section */
asymbol * newsym =
(asymbol *)bfd_make_empty_symbol(entry->the_bfd);
newsym->name = entry->local_sym_name;
/* The symbol belongs to the output file's text section */
/* The value is the start of this section in the output file*/
newsym->value = 0;
newsym->flags = BSF_LOCAL;
newsym->section = s;
*output_buffer++ = newsym;
break;
}
}
}
for (i = 0; i < entry->symbol_count; i++)
{
asymbol *p = entry->asymbols[i];
if (flag_is_global(p->flags) || flag_is_absolute(p->flags))
{
/* We are only interested in outputting
globals at this stage in special circumstances */
if (p->the_bfd == entry->the_bfd
&& flag_is_not_at_end(p->flags)) {
/* And this is one of them */
*(output_buffer++) = p;
p->flags |= BSF_KEEP;
}
}
else {
if (flag_is_ordinary_local(p->flags))
{
if (discard_locals == DISCARD_ALL)
{ }
else if (discard_locals == DISCARD_L &&
(p->name[0] == lprefix))
{ }
else if (p->flags == BSF_WARNING)
{ }
else
{ *output_buffer++ = p; }
}
else if (flag_is_debugger(p->flags))
{
/* Only keep the debugger symbols if no stripping required */
if (strip_symbols == STRIP_NONE) {
*output_buffer++ = p;
}
}
else if (flag_is_undefined(p->flags))
{ /* This must be global */
}
else if (flag_is_common(p->flags)) {
/* And so must this */
}
else if (p->flags & BSF_CTOR) {
/* Throw it away */
}
else
{
FAIL();
}
}
}
}
return output_buffer;
}
static asymbol **
write_file_globals(symbol_table)
asymbol **symbol_table;
{
FOR_EACH_LDSYM(sp)
{
if (sp->sdefs_chain != (asymbol **)NULL) {
asymbol *bufp = (*(sp->sdefs_chain));
if ((bufp->flags & BSF_KEEP) ==0) {
ASSERT(bufp != (asymbol *)NULL);
bufp->name = sp->name;
if (sp->scoms_chain != (asymbol **)NULL)
{
/*
defined as common but not allocated, this happens
only with -r and not -d, write out a common
definition
*/
bufp = *(sp->scoms_chain);
}
*symbol_table++ = bufp;
}
}
else if (sp->scoms_chain != (asymbol **)NULL) {
/* This symbol is a common - just output */
asymbol *bufp = (*(sp->scoms_chain));
*symbol_table++ = bufp;
}
else if (sp->srefs_chain != (asymbol **)NULL) {
/* This symbol is undefined but has a reference */
asymbol *bufp = (*(sp->srefs_chain));
*symbol_table++ = bufp;
}
else {
/*
This symbol has neither defs nor refs, it must have come
from the command line, since noone has used it it has no
data attatched, so we'll ignore it
*/
}
}
return symbol_table;
}
void
ldsym_write()
{
if (strip_symbols != STRIP_ALL) {
/* We know the maximum size of the symbol table -
it's the size of all the global symbols ever seen +
the size of all the symbols from all the files +
the number of files (for the per file symbols)
+1 (for the null at the end)
*/
extern unsigned int total_files_seen;
extern unsigned int total_symbols_seen;
asymbol ** symbol_table = (asymbol **)
ldmalloc ((size_t)(global_symbol_count +
total_files_seen +
total_symbols_seen + 1) * sizeof (asymbol *));
asymbol ** tablep = write_file_locals(symbol_table);
tablep = write_file_globals(tablep);
*tablep = (asymbol *)NULL;
bfd_set_symtab(output_bfd, symbol_table, (unsigned)( tablep - symbol_table));
}
}
/*
return true if the supplied symbol name is not in the
linker symbol table
*/
boolean
DEFUN(ldsym_undefined,(sym),
CONST char *sym)
{
ldsym_type *from_table = ldsym_get_soft(sym);
if (from_table != (ldsym_type *)NULL) {
if (from_table->sdefs_chain != (asymbol **)NULL) return false;
}
return true;
}
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