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@bernhardkaindl
Created April 8, 2023 11:18
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dwflmodtest.c Modifiled to use dwfl_report_elf() to get debug info for other elf files
/* Test program for libdwfl basic module tracking, relocation.
Copyright (C) 2005, 2007 Red Hat, Inc.
This file is part of elfutils.
This file 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 3 of the License, or
(at your option) any later version.
elfutils 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 this program. If not, see <http://www.gnu.org/licenses/>. */
//#include <config.h>
#include <assert.h>
#include <inttypes.h>
#include <sys/types.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <locale.h>
#include <argp.h>
#include <fcntl.h>
#include <dwarf.h>
#include <elfutils/libdwfl.h>
#define error printf
static bool show_inlines;
struct info
{
Dwarf_Die *cudie;
Dwarf_Addr dwbias;
};
static int
print_instance (Dwarf_Die *instance, void *arg)
{
const struct info *info = arg;
printf (" inlined");
Dwarf_Files *files;
if (dwarf_getsrcfiles (info->cudie, &files, NULL) == 0)
{
Dwarf_Attribute attr_mem;
Dwarf_Word val;
if (dwarf_formudata (dwarf_attr (instance, DW_AT_call_file,
&attr_mem), &val) == 0)
{
const char *file = dwarf_filesrc (files, val, NULL, NULL);
int lineno = 0, colno = 0;
if (dwarf_formudata (dwarf_attr (instance, DW_AT_call_line,
&attr_mem), &val) == 0)
lineno = val;
if (dwarf_formudata (dwarf_attr (instance, DW_AT_call_column,
&attr_mem), &val) == 0)
colno = val;
if (lineno == 0)
{
if (file != NULL)
printf (" from %s", file);
}
else if (colno == 0)
printf (" at %s:%u", file, lineno);
else
printf (" at %s:%u:%u", file, lineno, colno);
}
}
Dwarf_Addr lo = -1, hi = -1, entry = -1;
if (dwarf_lowpc (instance, &lo) == 0)
lo += info->dwbias;
else
printf (" (lowpc => %s)", dwarf_errmsg (-1));
if (dwarf_highpc (instance, &hi) == 0)
hi += info->dwbias;
else
printf (" (highpc => %s)", dwarf_errmsg (-1));
Dwarf_Attribute attr_mem;
Dwarf_Attribute *attr = dwarf_attr (instance, DW_AT_entry_pc, &attr_mem);
if (attr != NULL)
{
if (dwarf_formaddr (attr, &entry) == 0)
entry += info->dwbias;
else
printf (" (entrypc => %s)", dwarf_errmsg (-1));
}
if (lo != (Dwarf_Addr) -1 || hi != (Dwarf_Addr) -1)
printf (" %#" PRIx64 "..%#" PRIx64, lo, hi);
if (entry != (Dwarf_Addr) -1)
printf (" => %#" PRIx64 "\n", entry);
else
puts ("");
return DWARF_CB_OK;
}
static void
print_inline (Dwarf_Die *func, void *arg)
{
if (dwarf_func_inline_instances (func, &print_instance, arg) != 0)
printf (" error finding instances: %s\n", dwarf_errmsg (-1));
}
static int
print_func (Dwarf_Die *func, void *arg)
{
const struct info *info = arg;
const char *file = dwarf_decl_file (func);
int line = -1;
dwarf_decl_line (func, &line);
const char *fct = dwarf_diename (func);
printf (" %s:%d: %s:", file, line, fct);
if (dwarf_func_inline (func))
{
puts (" inline function");
if (show_inlines)
print_inline (func, arg);
}
else
{
Dwarf_Addr lo = -1, hi = -1, entry = -1;
if (dwarf_lowpc (func, &lo) == 0)
lo += info->dwbias;
else
printf (" (lowpc => %s)", dwarf_errmsg (-1));
if (dwarf_highpc (func, &hi) == 0)
hi += info->dwbias;
else
printf (" (highpc => %s)", dwarf_errmsg (-1));
if (dwarf_entrypc (func, &entry) == 0)
entry += info->dwbias;
else
printf (" (entrypc => %s)", dwarf_errmsg (-1));
if (lo != (Dwarf_Addr) -1 || hi != (Dwarf_Addr) -1
|| entry != (Dwarf_Addr) -1)
printf (" %#" PRIx64 "..%#" PRIx64 " => %#" PRIx64 "\n",
lo, hi, entry);
else
puts ("");
}
return DWARF_CB_OK;
}
static int
list_module (Dwfl_Module *mod __attribute__ ((unused)),
void **userdata __attribute__ ((unused)),
const char *name, Dwarf_Addr base,
void *arg __attribute__ ((unused)))
{
Dwarf_Addr start;
Dwarf_Addr end;
const char *file;
const char *debug;
if (dwfl_module_info (mod, NULL, &start, &end,
NULL, NULL, &file, &debug) != name
|| start != base)
abort ();
printf ("module: %30s %08" PRIx64 "..%08" PRIx64 " %s %s\n",
name, start, end, file, debug);
return DWARF_CB_OK;
}
static int
print_module (Dwfl_Module *mod __attribute__ ((unused)),
void **userdata __attribute__ ((unused)),
const char *name, Dwarf_Addr base,
Dwarf *dw, Dwarf_Addr bias,
void *arg)
{
printf ("module: %30s %08" PRIx64 " %s %" PRIx64 " (%s)\n",
name, base, dw == NULL ? "no" : "DWARF", bias, dwfl_errmsg (-1));
if (dw != NULL && *(const bool *) arg)
{
Dwarf_Off off = 0;
size_t cuhl;
Dwarf_Off noff;
while (dwarf_nextcu (dw, off, &noff, &cuhl, NULL, NULL, NULL) == 0)
{
Dwarf_Die die_mem;
struct info info = { dwarf_offdie (dw, off + cuhl, &die_mem), bias };
(void) dwarf_getfuncs (info.cudie, print_func, &info, 0);
off = noff;
}
}
return DWARF_CB_OK;
}
static bool show_functions;
/* gettext helper macro. */
#undef N_
#define N_(Str) Str
static const struct argp_option options[] =
{
{ "functions", 'f', NULL, 0, N_("Additionally show function names"), 0 },
{ "inlines", 'i', NULL, 0, N_("Show instances of inlined functions"), 0 },
{ NULL, 0, NULL, 0, NULL, 0 }
};
static error_t
parse_opt (int key, char *arg __attribute__ ((unused)),
struct argp_state *state __attribute__ ((unused)))
{
switch (key)
{
case ARGP_KEY_INIT:
state->child_inputs[0] = state->input;
break;
case 'f':
show_functions = true;
break;
case 'i':
show_inlines = show_functions = true;
break;
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
char *debuginfo_path = ".:/usr/lib/debuginfo";
Dwfl_Callbacks callbacks = {
.find_elf = dwfl_linux_proc_find_elf,
.find_debuginfo = dwfl_standard_find_debuginfo,
.debuginfo_path = &debuginfo_path,
};
int
main (int argc, char **argv)
{
/* We use no threads here which can interfere with handling a stream. */
(void) __fsetlocking (stdout, FSETLOCKING_BYCALLER);
/* Set locale. */
(void) setlocale (LC_ALL, "");
Dwfl *dwfl = NULL;
const struct argp_child argp_children[] =
{
{ .argp = dwfl_standard_argp () },
{ .argp = NULL }
};
const struct argp argp =
{
options, parse_opt, NULL, NULL, argp_children, NULL, NULL
};
(void) argp_parse (&argp, argc, argv, 0, NULL, &dwfl);
dwfl = dwfl_begin(&callbacks);
// const char*filename = "a.out";
const char*filename = "/usr/bin/pwd";
int fd = open(filename, O_RDONLY);
if (fd < 0) {
printf("cannot open debug info for %s: %m\n", filename);
return -1;
}
dwfl_report_elf(dwfl, filename, filename, fd, 0, true);
dwfl_report_end(dwfl, NULL, NULL);
//assert((dwmodule = dwfl_report_offline(dwfl, "", "stack-trace", -1)));
assert (dwfl != NULL);
ptrdiff_t p = 0;
do
p = dwfl_getmodules (dwfl, &list_module, NULL, p);
while (p > 0);
if (p < 0)
error ("dwfl_getmodules: %s", dwfl_errmsg (-1));
do
p = dwfl_getdwarf (dwfl, &print_module, &show_functions, p);
while (p > 0);
if (p < 0)
error ("dwfl_getdwarf: %s", dwfl_errmsg (-1));
p = 0;
do
p = dwfl_getmodules (dwfl, &list_module, NULL, p);
while (p > 0);
if (p < 0)
error ("dwfl_getmodules: %s", dwfl_errmsg (-1));
dwfl_end (dwfl);
return 0;
}
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