freebsd-dev/contrib/elftoolchain/addr2line/addr2line.c
Ed Maste 7a2e729ba2 addr2line: initialize die to NULL
GCC on MIPS produced a 'may be used uninitialized' warning after
r289071.

Reported by:	sbruno
Pointy hat to:	emaste
2015-10-09 18:26:24 +00:00

489 lines
12 KiB
C

/*-
* Copyright (c) 2009 Kai Wang
* 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <dwarf.h>
#include <err.h>
#include <fcntl.h>
#include <gelf.h>
#include <getopt.h>
#include <libdwarf.h>
#include <libelftc.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "_elftc.h"
ELFTC_VCSID("$Id: addr2line.c 3249 2015-10-04 08:11:30Z kaiwang27 $");
static struct option longopts[] = {
{"target" , required_argument, NULL, 'b'},
{"demangle", no_argument, NULL, 'C'},
{"exe", required_argument, NULL, 'e'},
{"functions", no_argument, NULL, 'f'},
{"section", required_argument, NULL, 'j'},
{"basename", no_argument, NULL, 's'},
{"help", no_argument, NULL, 'H'},
{"version", no_argument, NULL, 'V'},
{NULL, 0, NULL, 0}
};
static int demangle, func, base;
static char unknown[] = { '?', '?', '\0' };
static Dwarf_Addr section_base;
#define USAGE_MESSAGE "\
Usage: %s [options] hexaddress...\n\
Map program addresses to source file names and line numbers.\n\n\
Options:\n\
-b TGT | --target=TGT (Accepted but ignored).\n\
-e EXE | --exe=EXE Use program \"EXE\" to translate addresses.\n\
-f | --functions Display function names.\n\
-j NAME | --section=NAME Values are offsets into section \"NAME\".\n\
-s | --basename Only show the base name for each file name.\n\
-C | --demangle Demangle C++ names.\n\
-H | --help Print a help message.\n\
-V | --version Print a version identifier and exit.\n"
static void
usage(void)
{
(void) fprintf(stderr, USAGE_MESSAGE, ELFTC_GETPROGNAME());
exit(1);
}
static void
version(void)
{
fprintf(stderr, "%s (%s)\n", ELFTC_GETPROGNAME(), elftc_version());
exit(0);
}
/*
* Handle DWARF 4 'offset from' DW_AT_high_pc. Although we don't
* fully support DWARF 4, some compilers (like FreeBSD Clang 3.5.1)
* generate DW_AT_high_pc as an offset from DW_AT_low_pc.
*
* "If the value of the DW_AT_high_pc is of class address, it is the
* relocated address of the first location past the last instruction
* associated with the entity; if it is of class constant, the value
* is an unsigned integer offset which when added to the low PC gives
* the address of the first location past the last instruction
* associated with the entity."
*
* DWARF4 spec, section 2.17.2.
*/
static int
handle_high_pc(Dwarf_Die die, Dwarf_Unsigned lopc, Dwarf_Unsigned *hipc)
{
Dwarf_Error de;
Dwarf_Half form;
Dwarf_Attribute at;
int ret;
ret = dwarf_attr(die, DW_AT_high_pc, &at, &de);
if (ret == DW_DLV_ERROR) {
warnx("dwarf_attr failed: %s", dwarf_errmsg(de));
return (ret);
}
ret = dwarf_whatform(at, &form, &de);
if (ret == DW_DLV_ERROR) {
warnx("dwarf_whatform failed: %s", dwarf_errmsg(de));
return (ret);
}
if (dwarf_get_form_class(2, 0, 0, form) == DW_FORM_CLASS_CONSTANT)
*hipc += lopc;
return (DW_DLV_OK);
}
static void
search_func(Dwarf_Debug dbg, Dwarf_Die die, Dwarf_Addr addr, char **rlt_func)
{
Dwarf_Die ret_die, spec_die;
Dwarf_Error de;
Dwarf_Half tag;
Dwarf_Unsigned lopc, hipc;
Dwarf_Off ref;
Dwarf_Attribute sub_at, spec_at;
char *func0;
const char *func1;
int ret;
if (*rlt_func != NULL)
goto done;
if (dwarf_tag(die, &tag, &de)) {
warnx("dwarf_tag: %s", dwarf_errmsg(de));
goto cont_search;
}
if (tag == DW_TAG_subprogram) {
if (dwarf_attrval_unsigned(die, DW_AT_low_pc, &lopc, &de) ||
dwarf_attrval_unsigned(die, DW_AT_high_pc, &hipc, &de))
goto cont_search;
if (handle_high_pc(die, lopc, &hipc) != DW_DLV_OK)
goto cont_search;
if (addr < lopc || addr >= hipc)
goto cont_search;
/* Found it! */
if ((*rlt_func = strdup(unknown)) == NULL)
err(EXIT_FAILURE, "strdup");
ret = dwarf_attr(die, DW_AT_name, &sub_at, &de);
if (ret == DW_DLV_ERROR)
goto done;
if (ret == DW_DLV_OK) {
if (dwarf_formstring(sub_at, &func0, &de) ==
DW_DLV_OK) {
free(*rlt_func);
if ((*rlt_func = strdup(func0)) == NULL)
err(EXIT_FAILURE, "strdup");
}
goto done;
}
/*
* If DW_AT_name is not present, but DW_AT_specification is
* present, then probably the actual name is in the DIE
* referenced by DW_AT_specification.
*/
if (dwarf_attr(die, DW_AT_specification, &spec_at, &de))
goto done;
if (dwarf_global_formref(spec_at, &ref, &de))
goto done;
if (dwarf_offdie(dbg, ref, &spec_die, &de))
goto done;
if (dwarf_attrval_string(spec_die, DW_AT_name, &func1, &de) ==
DW_DLV_OK) {
free(*rlt_func);
if ((*rlt_func = strdup(func1)) == NULL)
err(EXIT_FAILURE, "strdup");
}
goto done;
}
cont_search:
/* Search children. */
ret = dwarf_child(die, &ret_die, &de);
if (ret == DW_DLV_ERROR)
errx(EXIT_FAILURE, "dwarf_child: %s", dwarf_errmsg(de));
else if (ret == DW_DLV_OK)
search_func(dbg, ret_die, addr, rlt_func);
/* Search sibling. */
ret = dwarf_siblingof(dbg, die, &ret_die, &de);
if (ret == DW_DLV_ERROR)
errx(EXIT_FAILURE, "dwarf_siblingof: %s", dwarf_errmsg(de));
else if (ret == DW_DLV_OK)
search_func(dbg, ret_die, addr, rlt_func);
done:
dwarf_dealloc(dbg, die, DW_DLA_DIE);
}
static void
translate(Dwarf_Debug dbg, const char* addrstr)
{
Dwarf_Die die, ret_die;
Dwarf_Line *lbuf;
Dwarf_Error de;
Dwarf_Half tag;
Dwarf_Unsigned lopc, hipc, addr, lineno, plineno;
Dwarf_Signed lcount;
Dwarf_Addr lineaddr, plineaddr;
char *funcname;
char *file, *file0, *pfile;
char demangled[1024];
int i, ret;
addr = strtoull(addrstr, NULL, 16);
addr += section_base;
lineno = 0;
file = unknown;
die = NULL;
lbuf = NULL;
lcount = 0;
while ((ret = dwarf_next_cu_header(dbg, NULL, NULL, NULL, NULL, NULL,
&de)) == DW_DLV_OK) {
die = NULL;
while (dwarf_siblingof(dbg, die, &ret_die, &de) == DW_DLV_OK) {
if (die != NULL)
dwarf_dealloc(dbg, die, DW_DLA_DIE);
die = ret_die;
if (dwarf_tag(die, &tag, &de) != DW_DLV_OK) {
warnx("dwarf_tag failed: %s",
dwarf_errmsg(de));
goto next_cu;
}
/* XXX: What about DW_TAG_partial_unit? */
if (tag == DW_TAG_compile_unit)
break;
}
if (ret_die == NULL) {
warnx("could not find DW_TAG_compile_unit die");
goto next_cu;
}
if (!dwarf_attrval_unsigned(die, DW_AT_low_pc, &lopc, &de) &&
!dwarf_attrval_unsigned(die, DW_AT_high_pc, &hipc, &de)) {
/*
* Check if the address falls into the PC range of
* this CU.
*/
if (handle_high_pc(die, lopc, &hipc) != DW_DLV_OK)
goto next_cu;
if (addr < lopc || addr >= hipc)
goto next_cu;
}
switch (dwarf_srclines(die, &lbuf, &lcount, &de)) {
case DW_DLV_OK:
break;
case DW_DLV_NO_ENTRY:
/* If a CU lacks debug info, just skip it. */
goto next_cu;
default:
warnx("dwarf_srclines: %s", dwarf_errmsg(de));
goto out;
}
plineaddr = ~0ULL;
plineno = 0;
pfile = unknown;
for (i = 0; i < lcount; i++) {
if (dwarf_lineaddr(lbuf[i], &lineaddr, &de)) {
warnx("dwarf_lineaddr: %s",
dwarf_errmsg(de));
goto out;
}
if (dwarf_lineno(lbuf[i], &lineno, &de)) {
warnx("dwarf_lineno: %s",
dwarf_errmsg(de));
goto out;
}
if (dwarf_linesrc(lbuf[i], &file0, &de)) {
warnx("dwarf_linesrc: %s",
dwarf_errmsg(de));
} else
file = file0;
if (addr == lineaddr)
goto out;
else if (addr < lineaddr && addr > plineaddr) {
lineno = plineno;
file = pfile;
goto out;
}
plineaddr = lineaddr;
plineno = lineno;
pfile = file;
}
next_cu:
if (die != NULL) {
dwarf_dealloc(dbg, die, DW_DLA_DIE);
die = NULL;
}
}
out:
funcname = NULL;
if (ret == DW_DLV_OK && func) {
search_func(dbg, die, addr, &funcname);
die = NULL;
}
if (func) {
if (funcname == NULL)
if ((funcname = strdup(unknown)) == NULL)
err(EXIT_FAILURE, "strdup");
if (demangle &&
!elftc_demangle(funcname, demangled, sizeof(demangled), 0))
printf("%s\n", demangled);
else
printf("%s\n", funcname);
free(funcname);
}
(void) printf("%s:%ju\n", base ? basename(file) : file, lineno);
if (die != NULL)
dwarf_dealloc(dbg, die, DW_DLA_DIE);
/*
* Reset internal CU pointer, so we will start from the first CU
* next round.
*/
while (ret != DW_DLV_NO_ENTRY) {
if (ret == DW_DLV_ERROR)
errx(EXIT_FAILURE, "dwarf_next_cu_header: %s",
dwarf_errmsg(de));
ret = dwarf_next_cu_header(dbg, NULL, NULL, NULL, NULL, NULL,
&de);
}
}
static void
find_section_base(const char *exe, Elf *e, const char *section)
{
Dwarf_Addr off;
Elf_Scn *scn;
GElf_Ehdr eh;
GElf_Shdr sh;
size_t shstrndx;
int elferr;
const char *name;
if (gelf_getehdr(e, &eh) != &eh) {
warnx("gelf_getehdr failed: %s", elf_errmsg(-1));
return;
}
if (!elf_getshstrndx(e, &shstrndx)) {
warnx("elf_getshstrndx failed: %s", elf_errmsg(-1));
return;
}
(void) elf_errno();
off = 0;
scn = NULL;
while ((scn = elf_nextscn(e, scn)) != NULL) {
if (gelf_getshdr(scn, &sh) == NULL) {
warnx("gelf_getshdr failed: %s", elf_errmsg(-1));
continue;
}
if ((name = elf_strptr(e, shstrndx, sh.sh_name)) == NULL)
goto next;
if (!strcmp(section, name)) {
if (eh.e_type == ET_EXEC || eh.e_type == ET_DYN) {
/*
* For executables, section base is the virtual
* address of the specified section.
*/
section_base = sh.sh_addr;
} else if (eh.e_type == ET_REL) {
/*
* For relocatables, section base is the
* relative offset of the specified section
* to the start of the first section.
*/
section_base = off;
} else
warnx("unknown e_type %u", eh.e_type);
return;
}
next:
off += sh.sh_size;
}
elferr = elf_errno();
if (elferr != 0)
warnx("elf_nextscn failed: %s", elf_errmsg(elferr));
errx(EXIT_FAILURE, "%s: cannot find section %s", exe, section);
}
int
main(int argc, char **argv)
{
Elf *e;
Dwarf_Debug dbg;
Dwarf_Error de;
const char *exe, *section;
char line[1024];
int fd, i, opt;
exe = NULL;
section = NULL;
while ((opt = getopt_long(argc, argv, "b:Ce:fj:sHV", longopts, NULL)) !=
-1) {
switch (opt) {
case 'b':
/* ignored */
break;
case 'C':
demangle = 1;
break;
case 'e':
exe = optarg;
break;
case 'f':
func = 1;
break;
case 'j':
section = optarg;
break;
case 's':
base = 1;
break;
case 'H':
usage();
case 'V':
version();
default:
usage();
}
}
argv += optind;
argc -= optind;
if (exe == NULL)
exe = "a.out";
if ((fd = open(exe, O_RDONLY)) < 0)
err(EXIT_FAILURE, "%s", exe);
if (dwarf_init(fd, DW_DLC_READ, NULL, NULL, &dbg, &de))
errx(EXIT_FAILURE, "dwarf_init: %s", dwarf_errmsg(de));
if (dwarf_get_elf(dbg, &e, &de) != DW_DLV_OK)
errx(EXIT_FAILURE, "dwarf_get_elf: %s", dwarf_errmsg(de));
if (section)
find_section_base(exe, e, section);
else
section_base = 0;
if (argc > 0)
for (i = 0; i < argc; i++)
translate(dbg, argv[i]);
else
while (fgets(line, sizeof(line), stdin) != NULL) {
translate(dbg, line);
fflush(stdout);
}
dwarf_finish(dbg, &de);
(void) elf_end(e);
exit(0);
}