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/* Test program for unwinding of complicated DWARF expressions.
Copyright (C) 2013, 2015, 2018 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 <inttypes.h>
#include <stdio_ext.h>
#include <locale.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include ELFUTILS_HEADER(dwfl)
#include "system.h"
#ifndef __linux__
int
main (int argc __attribute__ ((unused)), char **argv)
{
fprintf (stderr, "%s: Unwinding not supported for this architecture\n",
argv[0]);
return 77;
}
#else /* __linux__ */
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <signal.h>
#define main cleanup_13_main
#include "cleanup-13.c"
#undef main
static void
report_pid (Dwfl *dwfl, pid_t pid)
{
int result = dwfl_linux_proc_report (dwfl, pid);
if (result < 0)
error (2, 0, "dwfl_linux_proc_report: %s", dwfl_errmsg (-1));
else if (result > 0)
error (2, result, "dwfl_linux_proc_report");
if (dwfl_report_end (dwfl, NULL, NULL) != 0)
error (2, 0, "dwfl_report_end: %s", dwfl_errmsg (-1));
result = dwfl_linux_proc_attach (dwfl, pid, true);
if (result < 0)
error (2, 0, "dwfl_linux_proc_attach: %s", dwfl_errmsg (-1));
else if (result > 0)
error (2, result, "dwfl_linux_proc_attach");
}
static Dwfl *
pid_to_dwfl (pid_t pid)
{
static char *debuginfo_path;
static const Dwfl_Callbacks proc_callbacks =
{
.find_debuginfo = dwfl_standard_find_debuginfo,
.debuginfo_path = &debuginfo_path,
.find_elf = dwfl_linux_proc_find_elf,
};
Dwfl *dwfl = dwfl_begin (&proc_callbacks);
if (dwfl == NULL)
error (2, 0, "dwfl_begin: %s", dwfl_errmsg (-1));
report_pid (dwfl, pid);
return dwfl;
}
static int
frame_callback (Dwfl_Frame *state, void *frame_arg)
{
Dwarf_Addr pc;
bool isactivation;
if (! dwfl_frame_pc (state, &pc, &isactivation))
{
error (0, 0, "%s", dwfl_errmsg (-1));
return DWARF_CB_ABORT;
}
Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1);
/* Get PC->SYMNAME. */
Dwfl_Thread *thread = dwfl_frame_thread (state);
Dwfl *dwfl = dwfl_thread_dwfl (thread);
Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc_adjusted);
const char *symname = NULL;
if (mod)
symname = dwfl_module_addrname (mod, pc_adjusted);
printf ("%#" PRIx64 "\t%s\n", (uint64_t) pc, symname ?: "<null>");
if (symname && (strcmp (symname, "main") == 0
|| strcmp (symname, ".main") == 0))
{
kill (dwfl_pid (dwfl), SIGKILL);
exit (0);
}
return DWARF_CB_OK;
}
static int
thread_callback (Dwfl_Thread *thread, void *thread_arg)
{
if (dwfl_thread_getframes (thread, frame_callback, NULL) == -1)
error (1, 0, "dwfl_thread_getframes: %s", dwfl_errmsg (-1));
/* frame_callback shall exit (0) on success. */
printf ("dwfl_thread_getframes returned, main not found\n");
return DWARF_CB_ABORT;
}
int
__attribute__((section(".main"))) /* Defeat -freorder-blocks-and-partition */
main (int argc __attribute__ ((unused)), char **argv)
{
/* We use no threads here which can interfere with handling a stream. */
__fsetlocking (stdin, FSETLOCKING_BYCALLER);
__fsetlocking (stdout, FSETLOCKING_BYCALLER);
__fsetlocking (stderr, FSETLOCKING_BYCALLER);
/* Set locale. */
(void) setlocale (LC_ALL, "");
elf_version (EV_CURRENT);
pid_t pid = fork ();
switch (pid)
{
case -1:
perror ("fork failed");
exit (-1);
case 0:;
long l = ptrace (PTRACE_TRACEME, 0, NULL, NULL);
if (l != 0)
{
perror ("PTRACE_TRACEME failed");
exit (-1);
}
cleanup_13_main ();
printf ("cleanup_13_main returned, impossible...\n");
exit (-1);
default:
break;
}
errno = 0;
int status;
pid_t got = waitpid (pid, &status, 0);
if (got != pid)
error (1, errno, "waitpid returned %d", got);
if (!WIFSTOPPED (status))
error (1, 0, "unexpected wait status %u", status);
if (WSTOPSIG (status) != SIGABRT)
error (1, 0, "unexpected signal %u", WSTOPSIG (status));
Dwfl *dwfl = pid_to_dwfl (pid);
if (dwfl_getthreads (dwfl, thread_callback, NULL) == -1)
error (1, 0, "dwfl_getthreads: %s", dwfl_errmsg (-1));
/* There is an exit (0) call if we find the "main" frame, */
printf ("dwfl_getthreads returned, main not found\n");
exit (-1);
}
#endif /* ! __linux__ */
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