freebsd-dev/libexec/rtld-elf/debug.c
Matthew N. Dodd c5d061c17a Provide a mechanism for dumping relocation information.
Setting the LD_DUMP_REL_PRE or LD_DUMP_REL_POST environment variables
cause rtld-elf to output a table of all relocations.

This is useful for debugging.
2003-06-19 03:55:38 +00:00

144 lines
4.1 KiB
C

/*-
* Copyright 1996-1998 John D. Polstra.
* 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.
*
* 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.
*
* $FreeBSD$
*/
/*
* Support for printing debugging messages.
*/
#include <stdarg.h>
#include <stdio.h>
#include "debug.h"
#include "rtld.h"
static const char rel_header[] =
" symbol name r_info r_offset st_value st_size address value\n"
" ------------------------------------------------------------------------------\n";
static const char rel_format[] = " %-25s %6x %08x %08x %7d %10p %08x\n";
int debug = 0;
void
debug_printf(const char *format, ...)
{
if (debug) {
va_list ap;
va_start(ap, format);
fflush(stdout);
vfprintf(stderr, format, ap);
putc('\n', stderr);
va_end(ap);
}
}
void
dump_relocations (Obj_Entry *obj0)
{
Obj_Entry *obj;
for (obj = obj0; obj != NULL; obj = obj->next) {
dump_obj_relocations(obj);
}
}
void
dump_obj_relocations (Obj_Entry *obj)
{
printf("Object \"%s\", relocbase %p\n", obj->path, obj->relocbase);
if (obj->relsize) {
printf("Non-PLT Relocations: %ld\n",
(obj->relsize / sizeof(Elf_Rel)));
dump_Elf_Rel(obj, obj->rel, obj->relsize);
}
if (obj->relasize) {
printf("Non-PLT Relocations with Addend: %ld\n",
(obj->relasize / sizeof(Elf_Rela)));
dump_Elf_Rela(obj, obj->rela, obj->relasize);
}
if (obj->pltrelsize) {
printf("PLT Relocations: %ld\n",
(obj->pltrelsize / sizeof(Elf_Rel)));
dump_Elf_Rel(obj, obj->pltrel, obj->pltrelsize);
}
if (obj->pltrelasize) {
printf("PLT Relocations with Addend: %ld\n",
(obj->pltrelasize / sizeof(Elf_Rela)));
dump_Elf_Rela(obj, obj->pltrela, obj->pltrelasize);
}
}
void
dump_Elf_Rel (Obj_Entry *obj, const Elf_Rel *rel0, u_long relsize)
{
const Elf_Rel *rel;
const Elf_Rel *rellim;
const Elf_Sym *sym;
Elf_Addr *dstaddr;
printf("%s", rel_header);
rellim = (const Elf_Rel *)((char *)rel0 + relsize);
for (rel = rel0; rel < rellim; rel++) {
dstaddr = (Elf_Addr *)(obj->relocbase + rel->r_offset);
sym = obj->symtab + ELF_R_SYM(rel->r_info);
printf(rel_format,
obj->strtab + sym->st_name,
rel->r_info, rel->r_offset,
sym->st_value, sym->st_size,
dstaddr, *dstaddr);
}
return;
}
void
dump_Elf_Rela (Obj_Entry *obj, const Elf_Rela *rela0, u_long relasize)
{
const Elf_Rela *rela;
const Elf_Rela *relalim;
const Elf_Sym *sym;
Elf_Addr *dstaddr;
printf("%s", rel_header);
relalim = (const Elf_Rela *)((char *)rela0 + relasize);
for (rela = rela0; rela < relalim; rela++) {
dstaddr = (Elf_Addr *)(obj->relocbase + rela->r_offset);
sym = obj->symtab + ELF_R_SYM(rela->r_info);
printf(rel_format,
obj->strtab + sym->st_name,
rela->r_info, rela->r_offset,
sym->st_value, sym->st_size,
dstaddr, *dstaddr);
}
return;
}