OpenBSD-4.6/gnu/usr.bin/ld/rrs.c
/* $OpenBSD: rrs.c,v 1.12 2008/02/12 21:17:53 miod Exp $*/
/*
* Copyright (c) 1993 Paul Kranenburg
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Paul Kranenburg.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <err.h>
#include <fcntl.h>
#include <ranlib.h>
#include <a.out.h>
#include <stab.h>
#include <string.h>
#include "ld.h"
static struct _dynamic rrs_dyn; /* defined in link.h */
static struct so_debug rrs_so_debug; /* defined in link.h */
static struct section_dispatch_table rrs_sdt; /* defined in link.h */
static got_t *rrs_got;
static jmpslot_t *rrs_plt; /* defined in md.h */
static struct relocation_info *rrs_reloc;
static struct nzlist *rrs_symbols; /* RRS symbol table */
static char *rrs_strtab; /* RRS strings */
static struct rrs_hash *rrs_hashtab; /* RT hash table */
static struct shobj *rrs_shobjs;
char *rrs_search_paths; /* `-L' RT search */
static int rrs_search_paths_size;
static int reserved_rrs_relocs;
static int claimed_rrs_relocs;
static int discarded_rrs_relocs;
static int number_of_gotslots = 1;
static int number_of_jmpslots = 1;
static int number_of_rrs_hash_entries;
static int number_of_rrs_symbols;
static int rrs_strtab_size;
static int rrs_symbol_size;
static int current_jmpslot_offset;
static int current_got_offset;
static int max_got_offset;
static int min_got_offset;
static int got_origin;
static int current_hash_index;
int number_of_shobjs;
/* Convert a GOT offset into a table entry */
#define GOTP(off) ((got_t *)((long)rrs_got + got_origin + (off)))
struct shobj {
struct shobj *next;
struct file_entry *entry;
};
/*
RRS text segment:
+-------------------+ <-- sdt_rel (rrs_text_start)
| |
| relocation |
| |
+-------------------+ <-- <sdt>.sdt_hash
| |
| hash buckets |
| |
+-------------------+ <-- <sdt>.sdt_nzlist
| |
| symbols |
| |
+-------------------+ <-- <sdt>.sdt_strings
| |
| strings |
| |
+-------------------+ <-- <sdt>.sdt_sods
| |
| shobjs |
| |
+-------------------+
| |
| shobjs strings | <-- <shobj>.sod_name
| |
+-------------------+
RRS data segment:
+-------------------+ <-- __DYNAMIC (rrs_data_start)
| |
| _dymamic |
| |
+-------------------+ <-- __DYNAMIC.d_debug
| |
| so_debug |
| |
+-------------------+ <-- __DYNAMIC.d_un.d_sdt
| |
| sdt |
| |
+-------------------+ <-- sdt_got
| |
| _GOT_ | <-- _GLOBAL_OFFSET_TABLE_
| | ( == sdt_got + got_origin)
| |
+-------------------+ <-- sdt_plt
| |
| PLT |
| |
+-------------------+
*/
static int
dlopen_is_used(void)
{
symbol *sym;
struct localsymbol *lsp;
#ifdef nounderscore
sym = getsym_soft("dlopen");
#else
sym = getsym_soft("_dlopen");
#endif
if (!sym)
return 0;
/*
* A use is characterized as being an entry on the "refs" list
* that is not in the text section, because such an entry is the
* definition.
*/
for (lsp = sym->refs; lsp; lsp = lsp->next)
if (!(lsp->nzlist.nlist.n_type & N_TEXT))
return 1;
return 0;
}
/*
* Add NAME to the list of needed run-time objects.
* Return 1 if ENTRY was added to the list.
*/
int
rrs_add_shobj(struct file_entry *entry)
{
struct shobj **p;
for (p = &rrs_shobjs; *p != NULL; p = &(*p)->next)
if (strcmp((*p)->entry->filename, entry->filename) == 0)
return 0;
*p = (struct shobj *)xmalloc(sizeof(struct shobj));
(*p)->next = NULL;
(*p)->entry = entry;
number_of_shobjs++;
return 1;
}
void
alloc_rrs_reloc(struct file_entry *entry, symbol *sp)
{
#ifdef DEBUG
printf("alloc_rrs_reloc: %s in %s\n", sp->name, get_file_name(entry));
#endif
reserved_rrs_relocs++;
}
void
alloc_rrs_segment_reloc(struct file_entry *entry, struct relocation_info *r)
{
#ifdef DEBUG
printf("alloc_rrs_segment_reloc at %#x in %s\n",
r->r_address, get_file_name(entry));
#endif
reserved_rrs_relocs++;
}
void
alloc_rrs_jmpslot(struct file_entry *entry, symbol *sp)
{
if (sp->flags & GS_HASJMPSLOT)
return;
sp->flags |= GS_HASJMPSLOT;
number_of_jmpslots++;
reserved_rrs_relocs++;
}
void
alloc_rrs_gotslot(struct file_entry *entry, struct relocation_info *r,
struct localsymbol *lsp)
{
symbol *sp = lsp->symbol;
if (!RELOC_EXTERN_P(r)) {
if (sp != NULL) {
warnx("%s: relocation for internal symbol "
"expected at %#x",
get_file_name(entry), RELOC_ADDRESS(r));
return;
}
if (!RELOC_STATICS_THROUGH_GOT_P(r))
/* No need for a GOT slot */
return;
if (lsp->flags & LS_HASGOTSLOT)
return;
lsp->flags |= LS_HASGOTSLOT;
} else {
if (sp == NULL) {
warnx("%s: relocation must refer "
"to global symbol at %#x",
get_file_name(entry), RELOC_ADDRESS(r));
return;
}
if (sp->alias)
sp = sp->alias;
if (sp->flags & GS_HASGOTSLOT)
return;
sp->flags |= GS_HASGOTSLOT;
}
number_of_gotslots++;
reserved_rrs_relocs++;
}
void
alloc_rrs_cpy_reloc(struct file_entry *entry, symbol *sp)
{
if (sp->flags & GS_CPYRELOCRESERVED)
return;
#ifdef DEBUG
printf("alloc_rrs_copy: %s in %s\n", sp->name, get_file_name(entry));
#endif
sp->flags |= GS_CPYRELOCRESERVED;
reserved_rrs_relocs++;
}
static struct relocation_info *
rrs_next_reloc(void)
{
struct relocation_info *r;
r = rrs_reloc + claimed_rrs_relocs++;
if (claimed_rrs_relocs > reserved_rrs_relocs)
errx(1, "internal error: RRS relocs exceed allocation %d",
reserved_rrs_relocs);
return r;
}
/* don't warn more than n times for text relocations */
#define TEXT_RELOC_THRESHOLD 3
static unsigned long total_text_relocs = 0;
/* called at cleanup time */
void
rrs_summarize_warnings(void)
{
if (total_text_relocs >= TEXT_RELOC_THRESHOLD)
warnx("Total: %lu RRS text relocations",
total_text_relocs);
}
/*
* Claim a RRS relocation as a result of a regular (ie. non-PIC)
* relocation record in a rel file.
*
* Return 1 if the output file needs no further updating.
* Return 0 if the relocation value pointed to by RELOCATION must
* written to a.out.
*/
int
claim_rrs_reloc(struct file_entry *entry, struct relocation_info *rp,
symbol *sp, long *relocation)
{
struct relocation_info *r = rrs_next_reloc();
if (rp->r_address < text_start + text_size &&
++total_text_relocs < TEXT_RELOC_THRESHOLD)
warnx("%s: RRS text relocation at %#x for \"%s\"",
get_file_name(entry), rp->r_address, sp->name);
#ifdef DEBUG
printf("claim_rrs_reloc: %s in %s\n", sp->name, get_file_name(entry));
#endif
r->r_address = rp->r_address;
r->r_symbolnum = sp->rrs_symbolnum;
if (link_mode & SYMBOLIC) {
if (!sp->defined)
warnx("Cannot reduce symbol \"%s\" in %s",
sp->name, get_file_name(entry));
RELOC_EXTERN_P(r) = 0;
*relocation += sp->value;
(void) md_make_reloc(rp, r, RELTYPE_RELATIVE);
return 0;
} else {
RELOC_EXTERN_P(r) = 1;
return md_make_reloc(rp, r, RELTYPE_EXTERN);
}
}
/*
* Claim a jmpslot. Setup RRS relocation if claimed for the first time.
*/
long
claim_rrs_jmpslot(struct file_entry *entry, struct relocation_info *rp,
symbol *sp, long addend)
{
struct relocation_info *r;
if (!(sp->flags & GS_HASJMPSLOT))
errx(1, "internal error: "
"%s: claim_rrs_jmpslot: %s: no reservation",
get_file_name(entry),
sp->name);
if (sp->jmpslot_offset != -1)
return rrs_sdt.sdt_plt + sp->jmpslot_offset;
sp->jmpslot_offset = current_jmpslot_offset;
current_jmpslot_offset += sizeof(jmpslot_t);
#ifdef DEBUG
printf("claim_rrs_jmpslot: %s: %s(%d) -> offset %x\n",
get_file_name(entry),
sp->name, sp->rrs_symbolnum, sp->jmpslot_offset);
#endif
if ((link_mode & SYMBOLIC) || rrs_section_type == RRS_PARTIAL) {
if (!sp->defined)
warnx("Cannot reduce symbol \"%s\" in %s",
sp->name, get_file_name(entry));
md_fix_jmpslot( rrs_plt + sp->jmpslot_offset/sizeof(jmpslot_t),
rrs_sdt.sdt_plt + sp->jmpslot_offset,
sp->value);
if (rrs_section_type == RRS_PARTIAL || !JMPSLOT_NEEDS_RELOC) {
/* PLT is self-contained */
discarded_rrs_relocs++;
return rrs_sdt.sdt_plt + sp->jmpslot_offset;
}
} else {
md_make_jmpslot(rrs_plt + sp->jmpslot_offset/sizeof(jmpslot_t),
sp->jmpslot_offset,
claimed_rrs_relocs);
}
/*
* Install a run-time relocation for this PLT entry.
*/
r = rrs_next_reloc();
RELOC_SYMBOL(r) = sp->rrs_symbolnum;
r->r_address = (long)rrs_sdt.sdt_plt + sp->jmpslot_offset;
if (link_mode & SYMBOLIC) {
RELOC_EXTERN_P(r) = 0;
md_make_jmpreloc(rp, r, RELTYPE_RELATIVE);
} else {
RELOC_EXTERN_P(r) = 1;
md_make_jmpreloc(rp, r, 0);
}
return rrs_sdt.sdt_plt + sp->jmpslot_offset;
}
/*
* Claim GOT entry for a global symbol. If this is the first relocation
* claiming the entry, setup a RRS relocation for it.
* Return offset into the GOT allocated to this symbol.
*/
long
claim_rrs_gotslot(struct file_entry *entry, struct relocation_info *rp,
struct localsymbol *lsp, long addend)
{
struct relocation_info *r;
symbol *sp = lsp->symbol;
int reloc_type = 0;
if (sp == NULL) {
return 0;
}
if (sp->alias)
sp = sp->alias;
if (!(sp->flags & GS_HASGOTSLOT))
errx(1, "internal error: "
"%s: claim_rrs_gotslot: %s: no reservation",
get_file_name(entry), sp->name);
if (sp->gotslot_offset != -1) {
#ifdef DIAGNOSTIC
if (*GOTP(sp->gotslot_offset) != addend +
((!(link_mode & SHAREABLE) || (link_mode & SYMBOLIC))
? sp->value : 0))
errx(1, "%s: %s: gotslot at %#x is multiple valued, "
"*got = %#x, addend = %#x, sp->value = %#x",
get_file_name(entry), sp->name,
sp->gotslot_offset,
*GOTP(sp->gotslot_offset), addend, sp->value);
#endif
/* This symbol already passed here before. */
return sp->gotslot_offset;
}
if (current_got_offset == 0)
/* GOT offset 0 is reserved */
current_got_offset += sizeof(got_t);
if (current_got_offset > max_got_offset)
errx(1, "%s: GOT overflow on symbol `%s' at %#x",
get_file_name(entry), sp->name, RELOC_ADDRESS(rp));
sp->gotslot_offset = current_got_offset;
current_got_offset += sizeof(got_t);
#ifdef DEBUG
printf("claim_rrs_gotslot: %s(%d,%#x) slot offset %#x, addend %#x\n",
sp->name, sp->rrs_symbolnum, sp->value, sp->gotslot_offset, addend);
#endif
if (sp->defined &&
(!(link_mode & SHAREABLE) || (link_mode & SYMBOLIC))) {
/*
* Reduce to just a base-relative translation.
*/
*GOTP(sp->gotslot_offset) = sp->value + addend;
reloc_type = RELTYPE_RELATIVE;
} else if ((link_mode & SYMBOLIC) || rrs_section_type == RRS_PARTIAL) {
/*
* SYMBOLIC: all symbols must be known.
* RRS_PARTIAL: we don't link against shared objects,
* so again all symbols must be known.
*/
warnx("Cannot reduce symbol \"%s\" in %s",
sp->name, get_file_name(entry));
} else {
/*
* This gotslot will be updated with symbol value at run-time.
*/
*GOTP(sp->gotslot_offset) = addend;
}
if (rrs_section_type == RRS_PARTIAL) {
/*
* Base address is known, gotslot should be fully
* relocated by now.
* NOTE: RRS_PARTIAL implies !SHAREABLE.
*/
if (!sp->defined)
warnx("Cannot reduce symbol \"%s\" in %s",
sp->name, get_file_name(entry));
discarded_rrs_relocs++;
return sp->gotslot_offset;
}
/*
* Claim a relocation entry.
* If symbol is defined and in "main" (!SHAREABLE)
* we still put out a relocation as we cannot easily
* undo the allocation.
* `RELTYPE_RELATIVE' relocations have the external bit off
* as no symbol need be looked up at run-time.
*/
r = rrs_next_reloc();
r->r_address = got_symbol->value + sp->gotslot_offset;
RELOC_SYMBOL(r) = sp->rrs_symbolnum;
RELOC_EXTERN_P(r) = !(reloc_type == RELTYPE_RELATIVE);
md_make_gotreloc(rp, r, reloc_type);
return sp->gotslot_offset;
}
/*
* Claim a GOT entry for a static symbol. Return offset of the
* allocated GOT entry. If RELOC_STATICS_THROUGH_GOT_P is in effect,
* return the offset of the symbol with respect to the *location* of
* the GOT.
*/
long
claim_rrs_internal_gotslot(struct file_entry *entry, struct relocation_info *rp,
struct localsymbol *lsp, long addend)
{
struct relocation_info *r;
addend += lsp->nzlist.nz_value;
if (!RELOC_STATICS_THROUGH_GOT_P(r))
return addend - got_symbol->value;
if (!(lsp->flags & LS_HASGOTSLOT))
errx(1, "internal error: "
"%s: claim_rrs_internal_gotslot at %#x: no reservation",
get_file_name(entry), RELOC_ADDRESS(rp));
if (lsp->gotslot_offset != -1) {
/* Already claimed */
if (*GOTP(lsp->gotslot_offset) != addend)
errx(1, "%s: gotslot at %#lx is multiple valued",
get_file_name(entry), lsp->gotslot_offset);
return lsp->gotslot_offset;
}
if (current_got_offset == 0)
/* GOT offset 0 is reserved */
current_got_offset += sizeof(got_t);
if (current_got_offset > max_got_offset)
errx(1, "%s: GOT overflow for relocation at %#x",
get_file_name(entry), RELOC_ADDRESS(rp));
lsp->gotslot_offset = current_got_offset;
current_got_offset += sizeof(got_t);
*GOTP(lsp->gotslot_offset) = addend;
#ifdef DEBUG
printf("claim_rrs_internal_gotslot: %s: slot offset %#x, addend = %#x\n",
get_file_name(entry), lsp->gotslot_offset, addend);
#endif
if (rrs_section_type == RRS_PARTIAL) {
discarded_rrs_relocs++;
return lsp->gotslot_offset;
}
/*
* Relocation entry needed for this static GOT entry.
*/
r = rrs_next_reloc();
r->r_address = got_symbol->value + lsp->gotslot_offset;
RELOC_EXTERN_P(r) = 0;
md_make_gotreloc(rp, r, RELTYPE_RELATIVE);
return lsp->gotslot_offset;
}
void
claim_rrs_cpy_reloc(struct file_entry *entry, struct relocation_info *rp,
symbol *sp)
{
struct relocation_info *r;
if (sp->flags & GS_CPYRELOCCLAIMED)
return;
if (!(sp->flags & GS_CPYRELOCRESERVED))
errx(1, "internal error: "
"%s: claim_cpy_reloc: %s: no reservation",
get_file_name(entry), sp->name);
#ifdef DEBUG
printf("claim_rrs_copy: %s: %s -> %x\n",
get_file_name(entry), sp->name, sp->so_defined);
#endif
r = rrs_next_reloc();
sp->flags |= GS_CPYRELOCCLAIMED;
r->r_address = rp->r_address;
RELOC_SYMBOL(r) = sp->rrs_symbolnum;
RELOC_EXTERN_P(r) = RELOC_EXTERN_P(rp);
md_make_cpyreloc(rp, r);
}
void
claim_rrs_segment_reloc(struct file_entry *entry, struct relocation_info *rp)
{
struct relocation_info *r = rrs_next_reloc();
#ifdef DEBUG
printf("claim_rrs_segment_reloc: %s at %#x\n",
get_file_name(entry), rp->r_address);
#endif
r->r_address = rp->r_address;
RELOC_TYPE(r) = RELOC_TYPE(rp);
RELOC_EXTERN_P(r) = 0;
md_make_reloc(rp, r, RELTYPE_RELATIVE);
}
/*
* Fill the RRS hash table for the given symbol name.
* NOTE: the hash value computation must match the one in rtld.
*/
static void
rrs_insert_hash(char *cp, int index)
{
int hashval = 0;
struct rrs_hash *hp;
for (; *cp; cp++)
hashval = (hashval << 1) + *cp;
hashval = (hashval & 0x7fffffff) % rrs_sdt.sdt_buckets;
/* Get to the bucket */
hp = rrs_hashtab + hashval;
if (hp->rh_symbolnum == -1) {
/* Empty bucket, use it */
hp->rh_symbolnum = index;
hp->rh_next = 0;
return;
}
while (hp->rh_next != 0)
hp = rrs_hashtab + hp->rh_next;
hp->rh_next = current_hash_index++;
hp = rrs_hashtab + hp->rh_next;
hp->rh_symbolnum = index;
hp->rh_next = 0;
}
/*
* There are two interesting cases to consider here.
*
* 1) No shared objects were loaded, but there were PIC input rel files.
* In this case we must output a _GLOBAL_OFFSET_TABLE_ but no other
* RRS data. Also, the entries in the GOT must be fully resolved.
*
* 2) It's a genuine dynamically linked program, so the whole RRS scoop
* goes into a.out.
*/
void
consider_rrs_section_lengths(void)
{
int n;
struct shobj *shp;
#ifdef notyet
struct shobj **shpp;
/* We run into trouble with this as long as shared object symbols
are not checked for definitions */
/*
* First, determine the real number of shared objects we need.
*/
for (shpp = &rrs_shobjs; *shpp; shpp = &(*shpp)->next) {
while (*shpp && !((*shpp)->entry->flags & E_SYMBOLS_USED)) {
if (--number_of_shobjs < 0)
errx(1, "internal error: number_of_shobjs < 0");
*shpp = (*shpp)->next;
}
if (*shpp == NULL)
break;
}
#endif
/* First, determine what of the RRS we want */
if (relocatable_output)
rrs_section_type = RRS_NONE;
else if (link_mode & SHAREABLE)
rrs_section_type = RRS_FULL;
else if (number_of_shobjs == 0 && !dlopen_is_used()
/*&& !(link_mode & DYNAMIC)*/) {
/*
* First slots in both tables are reserved
* hence the "> 1" condition
*/
if (number_of_gotslots > 1 || number_of_jmpslots > 1)
rrs_section_type = RRS_PARTIAL;
else
rrs_section_type = RRS_NONE;
} else
rrs_section_type = RRS_FULL;
if (rrs_section_type == RRS_NONE) {
got_symbol->defined = 0;
if (reserved_rrs_relocs > 0)
errx(1, "internal error: empty RRS has reservations");
return;
}
rrs_symbol_size = LD_VERSION_NZLIST_P(soversion) ?
sizeof(struct nzlist) : sizeof(struct nlist);
/*
* If there is an entry point, __DYNAMIC must be referenced (usually
* from crt0), as this is the method used to determine whether the
* run-time linker must be called.
*/
if (!(link_mode & SHAREABLE) && !(dynamic_symbol->flags & GS_REFERENCED))
errx(1, "No reference to __DYNAMIC");
dynamic_symbol->flags |= GS_REFERENCED;
if (number_of_gotslots > 1)
got_symbol->flags |= GS_REFERENCED;
/* Next, allocate relocs, got and plt */
n = reserved_rrs_relocs * sizeof(struct relocation_info);
rrs_reloc = (struct relocation_info *)xmalloc(n);
bzero(rrs_reloc, n);
n = number_of_gotslots * sizeof(got_t);
rrs_got = (got_t *)xmalloc(n);
bzero(rrs_got, n);
n = number_of_jmpslots * sizeof(jmpslot_t);
rrs_plt = (jmpslot_t *)xmalloc(n);
bzero(rrs_plt, n);
/* Initialize first jmpslot */
md_fix_jmpslot(rrs_plt, 0, 0);
if (rrs_section_type == RRS_PARTIAL) {
rrs_data_size = number_of_gotslots * sizeof(got_t);
rrs_data_size += number_of_jmpslots * sizeof(jmpslot_t);
return;
}
/*
* Walk the symbol table, assign RRS symbol numbers
* and calculate string space.
* Assign number 0 to __DYNAMIC (!! Sun compatibility)
*/
dynamic_symbol->rrs_symbolnum = number_of_rrs_symbols++;
FOR_EACH_SYMBOL(i ,sp) {
if ((link_mode & SHAREABLE) && sp->warning) {
/* Allocate N_WARNING & co */
rrs_strtab_size +=
2 + strlen(sp->name) + strlen(sp->warning);
number_of_rrs_symbols += 2;
}
if (!(sp->flags & GS_REFERENCED))
continue;
rrs_strtab_size += 1 + strlen(sp->name);
if (sp != dynamic_symbol)
sp->rrs_symbolnum = number_of_rrs_symbols++;
if (sp->alias) {
/*
* (sigh) Always allocate space to hold the
* indirection. At this point there's not
* enough information to decide whether it's
* actually needed or not.
*/
number_of_rrs_symbols++;
rrs_strtab_size += 1 + strlen(sp->alias->name);
}
} END_EACH_SYMBOL;
/*
* Now that we know how many RRS symbols there are going to be,
* allocate and initialize the RRS symbol hash table.
*/
rrs_sdt.sdt_buckets = number_of_rrs_symbols/4;
if (rrs_sdt.sdt_buckets < 4)
rrs_sdt.sdt_buckets = 4;
number_of_rrs_hash_entries = rrs_sdt.sdt_buckets +
number_of_rrs_symbols;
rrs_hashtab = (struct rrs_hash *)xmalloc(
number_of_rrs_hash_entries * sizeof(struct rrs_hash));
for (n = 0; n < rrs_sdt.sdt_buckets; n++)
rrs_hashtab[n].rh_symbolnum = -1;
current_hash_index = rrs_sdt.sdt_buckets;
/*
* Get symbols into hash table now, so we can fine tune the size
* of the latter. We adjust the value of `number_of_rrs_hash_entries'
* to the number of hash link slots actually used.
*/
FOR_EACH_SYMBOL(i ,sp) {
if (sp->flags & GS_REFERENCED)
rrs_insert_hash(sp->name, sp->rrs_symbolnum);
} END_EACH_SYMBOL;
number_of_rrs_hash_entries = current_hash_index;
/*
* Calculate RRS section sizes.
*/
rrs_data_size = sizeof(struct _dynamic);
rrs_data_size += sizeof(struct so_debug);
rrs_data_size += sizeof(struct section_dispatch_table);
rrs_data_size += number_of_gotslots * sizeof(got_t);
rrs_data_size += number_of_jmpslots * sizeof(jmpslot_t);
rrs_data_size = MALIGN(rrs_data_size);
rrs_text_size = reserved_rrs_relocs * sizeof(struct relocation_info);
rrs_text_size += number_of_rrs_hash_entries * sizeof(struct rrs_hash);
rrs_text_size += number_of_rrs_symbols * rrs_symbol_size;
rrs_search_paths_size = rrs_search_paths
? strlen(rrs_search_paths) + 1
: 0;
rrs_search_paths_size = MALIGN(rrs_search_paths_size);
rrs_text_size += rrs_search_paths_size;
/* Align strings size */
rrs_strtab_size = MALIGN(rrs_strtab_size);
rrs_text_size += rrs_strtab_size;
/* Process needed shared objects */
for (shp = rrs_shobjs; shp; shp = shp->next) {
char *name = shp->entry->local_sym_name;
if (*name == '-' && *(name+1) == 'l')
name += 2;
rrs_text_size += sizeof(struct sod);
rrs_text_size += 1 + strlen(name);
}
/* Finally, align size */
rrs_text_size = MALIGN(rrs_text_size);
}
void
relocate_rrs_addresses(void)
{
int gotsize;
dynamic_symbol->value = 0;
/*
* Get ready to allocate linkage table offsets.
* First jmpslot is reserved for the run-time binder
* GOT entry at offset 0 is reserved for `__DYNAMIC'.
*/
current_jmpslot_offset = sizeof(jmpslot_t);
current_got_offset = 0;
max_got_offset = MAX_GOTOFF(pic_type);
min_got_offset = MIN_GOTOFF(pic_type);
gotsize = number_of_gotslots * sizeof(got_t);
if (gotsize + min_got_offset - (int)sizeof(got_t) > max_got_offset)
warnx("Global Offset Table overflow (use `-fPIC')");
if (gotsize > max_got_offset)
/* Position at "two-complements" origin */
current_got_offset += min_got_offset;
got_origin = -current_got_offset;
if (rrs_section_type == RRS_NONE)
return;
if (rrs_section_type == RRS_PARTIAL) {
rrs_sdt.sdt_got = rrs_data_start;
got_symbol->value = rrs_sdt.sdt_got + got_origin;
rrs_sdt.sdt_plt = rrs_sdt.sdt_got +
number_of_gotslots * sizeof(got_t);
return;
}
/*
* RRS data relocations.
*/
rrs_dyn.d_version = soversion;
rrs_dyn.d_debug = (struct so_debug *)
(rrs_data_start + sizeof(struct _dynamic));
rrs_dyn.d_un.d_sdt = (struct section_dispatch_table *)
((long)rrs_dyn.d_debug + sizeof(struct so_debug));
rrs_sdt.sdt_got = (long)rrs_dyn.d_un.d_sdt +
sizeof(struct section_dispatch_table);
rrs_sdt.sdt_plt = rrs_sdt.sdt_got + number_of_gotslots*sizeof(got_t);
/*
* RRS text relocations.
*/
rrs_sdt.sdt_rel = rrs_text_start;
/*
* Sun BUG compatibility alert.
* Main program's RRS text values are relative to TXTADDR? WHY??
*/
#ifdef SUN_COMPAT
if (soversion == LD_VERSION_SUN && !(link_mode & SHAREABLE))
rrs_sdt.sdt_rel -= N_TXTADDR(outheader);
#endif
rrs_sdt.sdt_hash = rrs_sdt.sdt_rel +
reserved_rrs_relocs * sizeof(struct relocation_info);
rrs_sdt.sdt_nzlist = rrs_sdt.sdt_hash +
number_of_rrs_hash_entries * sizeof(struct rrs_hash);
rrs_sdt.sdt_strings = rrs_sdt.sdt_nzlist +
number_of_rrs_symbols * rrs_symbol_size;
rrs_sdt.sdt_paths = rrs_search_paths
? rrs_sdt.sdt_strings + rrs_strtab_size
: 0;
rrs_sdt.sdt_sods = rrs_shobjs
? rrs_sdt.sdt_strings + rrs_strtab_size +
rrs_search_paths_size
: 0;
rrs_sdt.sdt_filler2 = 0;
rrs_sdt.sdt_str_sz = rrs_strtab_size;
rrs_sdt.sdt_text_sz = text_size;
rrs_sdt.sdt_plt_sz = number_of_jmpslots * sizeof(jmpslot_t);
/*
* Assign addresses to _GLOBAL_OFFSET_TABLE_ and __DYNAMIC.
* The value `&__DYNAMIC' is in the GOT table at offset 0.
*/
got_symbol->value = rrs_sdt.sdt_got + got_origin;
*GOTP(0) = dynamic_symbol->value = rrs_data_start;
}
static void
write_rrs_data(void)
{
long pos;
if (rrs_section_type == RRS_NONE)
return;
pos = rrs_data_start + (N_DATOFF(outheader) - DATA_START(outheader));
if (fseek(outstream, pos, SEEK_SET) != 0)
err(1, "write_rrs_data: fseek");
if (rrs_section_type == RRS_PARTIAL) {
/*
* Only a GOT and PLT are needed.
*/
md_swapout_got(rrs_got, number_of_gotslots);
mywrite(rrs_got, number_of_gotslots, sizeof(got_t), outstream);
md_swapout_jmpslot(rrs_plt, number_of_jmpslots);
mywrite(rrs_plt, number_of_jmpslots,
sizeof(jmpslot_t), outstream);
return;
}
md_swapout__dynamic(&rrs_dyn);
mywrite(&rrs_dyn, 1, sizeof(struct _dynamic), outstream);
md_swapout_so_debug(&rrs_so_debug);
mywrite(&rrs_so_debug, 1, sizeof(struct so_debug), outstream);
md_swapout_section_dispatch_table(&rrs_sdt);
mywrite(&rrs_sdt, 1, sizeof(struct section_dispatch_table), outstream);
md_swapout_got(rrs_got, number_of_gotslots);
mywrite(rrs_got, number_of_gotslots, sizeof(got_t), outstream);
md_swapout_jmpslot(rrs_plt, number_of_jmpslots);
mywrite(rrs_plt, number_of_jmpslots, sizeof(jmpslot_t), outstream);
}
static void
write_rrs_text(void)
{
long pos;
int i;
int symsize;
struct nzlist *nlp;
int offset = 0;
struct shobj *shp;
struct sod *sodp;
int bind;
if (rrs_section_type == RRS_PARTIAL)
return;
pos = rrs_text_start + (N_TXTOFF(outheader) - TEXT_START(outheader));
if (fseek(outstream, pos, SEEK_SET) != 0)
err(1, "write_rrs_text: fseek");
/* Write relocation records */
md_swapout_reloc(rrs_reloc, reserved_rrs_relocs);
mywrite(rrs_reloc, reserved_rrs_relocs,
sizeof(struct relocation_info), outstream);
/* Write the RRS symbol hash tables */
md_swapout_rrs_hash(rrs_hashtab, number_of_rrs_hash_entries);
mywrite(rrs_hashtab, number_of_rrs_hash_entries,
sizeof(struct rrs_hash), outstream);
/*
* Determine size of an RRS symbol entry, allocate space
* to collect them in.
*/
symsize = number_of_rrs_symbols * rrs_symbol_size;
nlp = rrs_symbols = (struct nzlist *)alloca(symsize);
rrs_strtab = (char *)alloca(rrs_strtab_size);
#define INCR_NLP(p) ((p) = (struct nzlist *)((long)(p) + rrs_symbol_size))
/* __DYNAMIC symbol *must* be first for Sun compatibility */
nlp->nz_desc = nlp->nz_other = 0;
if (LD_VERSION_NZLIST_P(soversion))
nlp->nz_size = 0;
nlp->nz_type = dynamic_symbol->defined;
nlp->nz_value = dynamic_symbol->value;
nlp->nz_value = dynamic_symbol->value;
nlp->nz_strx = offset;
strlcpy(rrs_strtab + offset, dynamic_symbol->name, rrs_strtab_size - offset);
offset += 1 + strlen(dynamic_symbol->name);
INCR_NLP(nlp);
/*
* Now, for each global symbol, construct a nzlist element
* for inclusion in the RRS symbol table.
*/
FOR_EACH_SYMBOL(i, sp) {
if (sp == dynamic_symbol)
continue;
if ((link_mode & SHAREABLE) && sp->warning) {
/*
* Write a N_WARNING duo.
*/
nlp->nz_type = N_WARNING;
nlp->nz_un.n_strx = offset;
nlp->nz_value = 0;
nlp->nz_other = 0;
nlp->nz_desc = 0;
nlp->nz_size = 0;
strlcpy(rrs_strtab + offset, sp->warning,
rrs_strtab_size - offset);
offset += 1 + strlen(sp->warning);
INCR_NLP(nlp);
nlp->nz_type = N_UNDF + N_EXT;
nlp->nz_un.n_strx = offset;
nlp->nz_value = 0;
nlp->nz_other = 0;
nlp->nz_desc = 0;
nlp->nz_size = 0;
strlcpy(rrs_strtab + offset, sp->name,
rrs_strtab_size - offset);
offset += 1 + strlen(sp->name);
INCR_NLP(nlp);
}
if (!(sp->flags & GS_REFERENCED))
continue;
if ((long)nlp - (long)rrs_symbols >=
number_of_rrs_symbols * rrs_symbol_size)
errx(1, "internal error: "
"rrs symbols exceed allocation %d",
number_of_rrs_symbols);
nlp->nz_desc = 0;
nlp->nz_other = 0;
if (LD_VERSION_NZLIST_P(soversion))
nlp->nz_size = 0;
bind = (sp->flags & GS_WEAK) ? BIND_WEAK : 0;
if (sp->defined > 1) {
/* defined with known type */
if (!(link_mode & SHAREABLE) &&
sp->alias && sp->alias->defined > 1) {
/*
* If the target of an indirect symbol has
* been defined and we are outputting an
* executable, resolve the indirection; it's
* no longer needed.
*/
nlp->nz_type = sp->alias->defined;
nlp->nz_value = sp->alias->value;
nlp->nz_other = N_OTHER(bind, sp->alias->aux);
} else if (sp->defined == N_SIZE) {
/*
* Make sure this symbol isn't going
* to define anything.
*/
nlp->nz_type = N_UNDF;
nlp->nz_value = 0;
} else {
nlp->nz_type = sp->defined;
nlp->nz_value = sp->value;
nlp->nz_other = N_OTHER(bind, sp->aux);
}
if (LD_VERSION_NZLIST_P(soversion))
nlp->nz_size = sp->size;
} else if (sp->common_size) {
/*
* A common definition.
*/
nlp->nz_type = N_UNDF | N_EXT;
nlp->nz_value = sp->common_size;
nlp->nz_other = N_OTHER(bind, 0);
} else if (!sp->defined) {
/* undefined */
nlp->nz_type = N_UNDF | N_EXT;
nlp->nz_value = 0;
if (sp->so_defined && sp->jmpslot_offset != -1) {
/*
* A PLT entry. The auxiliary type -- which
* must be AUX_FUNC -- is used by the run-time
* linker to unambiguously resolve function
* address references.
*/
if (sp->aux != AUX_FUNC)
errx(1, "%s: non-function jmpslot",
sp->name);
nlp->nz_other = N_OTHER(bind, sp->aux);
nlp->nz_value =
rrs_sdt.sdt_plt + sp->jmpslot_offset;
}
} else
errx(1, "internal error: %s defined in mysterious way",
sp->name);
/* Set symbol's name */
nlp->nz_strx = offset;
strlcpy(rrs_strtab + offset, sp->name,
rrs_strtab_size - offset);
offset += 1 + strlen(sp->name);
if (sp->alias) {
/*
* Write an extra symbol for indirections (possibly
* just a dummy).
*/
int t = (nlp->nz_type == N_INDR + N_EXT);
INCR_NLP(nlp);
nlp->nz_type = N_UNDF + (t ? N_EXT : 0);
nlp->nz_un.n_strx = offset;
nlp->nz_value = 0;
nlp->nz_other = 0;
nlp->nz_desc = 0;
nlp->nz_size = 0;
strlcpy(rrs_strtab + offset, sp->alias->name,
rrs_strtab_size - offset);
offset += 1 + strlen(sp->alias->name);
}
INCR_NLP(nlp);
} END_EACH_SYMBOL;
if (MALIGN(offset) != rrs_strtab_size)
errx(1, "internal error: "
"inconsistent RRS string table length: %d, expected %d",
offset, rrs_strtab_size);
/* Write the symbol table */
if (rrs_symbol_size == sizeof(struct nlist)) {
md_swapout_symbols(rrs_symbols, number_of_rrs_symbols);
} else {
md_swapout_zsymbols(rrs_symbols, number_of_rrs_symbols);
}
mywrite(rrs_symbols, symsize, 1, outstream);
/* Write the strings */
mywrite(rrs_strtab, rrs_strtab_size, 1, outstream);
/* Write RT search path */
mywrite(rrs_search_paths, rrs_search_paths_size, 1, outstream);
/*
* Write the names of the shared objects needed at run-time
*/
pos = rrs_sdt.sdt_sods + number_of_shobjs * sizeof(struct sod);
sodp = (struct sod *)alloca( number_of_shobjs * sizeof(struct sod));
for (i = 0, shp = rrs_shobjs; shp; i++, shp = shp->next) {
char *name = shp->entry->local_sym_name;
if (i >= number_of_shobjs)
errx(1, "internal error: # of link objects exceeds %d",
number_of_shobjs);
sodp[i].sod_name = pos;
sodp[i].sod_major = shp->entry->lib_major;
sodp[i].sod_minor = shp->entry->lib_minor;
if (*name == '-' && *(name+1) == 'l') {
name += 2;
sodp[i].sod_library = 1;
} else
sodp[i].sod_library = 0;
pos += 1 + strlen(name);
sodp[i].sod_next = (i == number_of_shobjs - 1) ? 0 :
(rrs_sdt.sdt_sods + (i+1)*sizeof(struct sod));
}
if (i < number_of_shobjs)
errx(1, "internal error: "
"# of link objects less then expected %d",
number_of_shobjs);
md_swapout_sod(sodp, number_of_shobjs);
mywrite(sodp, number_of_shobjs, sizeof(struct sod), outstream);
for (i = 0, shp = rrs_shobjs; shp; i++, shp = shp->next) {
char *name = shp->entry->local_sym_name;
if (*name == '-' && *(name+1) == 'l') {
name += 2;
}
mywrite(name, strlen(name) + 1, 1, outstream);
}
}
void
write_rrs(void)
{
/*
* First, do some consistency checks on the RRS segment.
*/
if (rrs_section_type == RRS_NONE) {
if (reserved_rrs_relocs > 1)
errx(1, "internal error: "
"RRS relocs in static program: %d",
reserved_rrs_relocs-1);
return;
}
#ifdef DEBUG
printf("rrs_relocs: reserved %d claimed %d discarded %d, gotslots %d jmpslots %d\n",
reserved_rrs_relocs, claimed_rrs_relocs, discarded_rrs_relocs,
number_of_gotslots-1, number_of_jmpslots-1);
#endif
/* Final consistency check */
if (claimed_rrs_relocs + discarded_rrs_relocs != reserved_rrs_relocs) {
errx(1, "internal error: "
"reserved relocs(%d) != claimed(%d) + discarded(%d)",
reserved_rrs_relocs,
claimed_rrs_relocs,
discarded_rrs_relocs);
}
/* Write the RRS segments. */
write_rrs_text ();
write_rrs_data ();
}