1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-26 11:47:31 +00:00
freebsd/libexec/rtld-elf/debug.c
Konstantin Belousov 0e9a260520 Rtld links with the specially built pic static libc library to get some
C runtime services, like printf(). Unfortunately, the multithread-safeness
measures in the libc do not work in rtld environment.

Rip the kernel printf() implementation and use it in the rtld instead of
libc version. This printf does not require any shared global data and thus
is mt-safe. Systematically use rtld_printf() and related functions, remove
the calls to err(3).

Note that stdio is still pulled from libc due to libmap implementaion using
fopen(). This is safe but unoptimal, and can be changed later.

Reported and tested by:	pgj
Diagnosed and reviewed by:	kan (previous version)
Approved by:	re (bz)
2011-08-24 20:05:13 +00:00

144 lines
4.2 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"
#include "rtld_printf.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 %6lx %08lx %08lx %7d %10p %08lx\n";
int debug = 0;
void
debug_printf(const char *format, ...)
{
if (debug) {
va_list ap;
va_start(ap, format);
rtld_vfdprintf(STDERR_FILENO, format, ap);
rtld_fdputchar(STDERR_FILENO, '\n');
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)
{
rtld_printf("Object \"%s\", relocbase %p\n", obj->path, obj->relocbase);
if (obj->relsize) {
rtld_printf("Non-PLT Relocations: %ld\n",
(obj->relsize / sizeof(Elf_Rel)));
dump_Elf_Rel(obj, obj->rel, obj->relsize);
}
if (obj->relasize) {
rtld_printf("Non-PLT Relocations with Addend: %ld\n",
(obj->relasize / sizeof(Elf_Rela)));
dump_Elf_Rela(obj, obj->rela, obj->relasize);
}
if (obj->pltrelsize) {
rtld_printf("PLT Relocations: %ld\n",
(obj->pltrelsize / sizeof(Elf_Rel)));
dump_Elf_Rel(obj, obj->pltrel, obj->pltrelsize);
}
if (obj->pltrelasize) {
rtld_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;
rtld_putstr(rel_header);
rellim = (const Elf_Rel *)((const 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);
rtld_printf(rel_format,
obj->strtab + sym->st_name,
(u_long)rel->r_info, (u_long)rel->r_offset,
(u_long)sym->st_value, (int)sym->st_size,
dstaddr, (u_long)*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;
rtld_putstr(rel_header);
relalim = (const Elf_Rela *)((const 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);
rtld_printf(rel_format,
obj->strtab + sym->st_name,
(u_long)rela->r_info, (u_long)rela->r_offset,
(u_long)sym->st_value, (int)sym->st_size,
dstaddr, (u_long)*dstaddr);
}
return;
}