/* show_backtrace displays the backtrace, currently obtained by means of
the glibc backtrace* functions. */
void
show_backtrace (void)
{
#if GLIBC_BACKTRACE
#define DEPTH 50
#define BUFSIZE 1024
void *trace[DEPTH];
char **str;
int depth;
depth = backtrace (trace, DEPTH);
if (depth <= 0)
return;
str = backtrace_symbols (trace, depth);
#if CAN_PIPE
#ifndef STDIN_FILENO
#define STDIN_FILENO 0
#endif
#ifndef STDOUT_FILENO
#define STDOUT_FILENO 1
#endif
#ifndef STDERR_FILENO
#define STDERR_FILENO 2
#endif
/* We attempt to extract file and line information from addr2line. */
do
{
/* Local variables. */
int f[2], pid, line, i;
FILE *output;
char addr_buf[DEPTH][GFC_XTOA_BUF_SIZE], func[BUFSIZE], file[BUFSIZE];
char *p, *end;
const char *addr[DEPTH];
/* Write the list of addresses in hexadecimal format. */
for (i = 0; i < depth; i++)
addr[i] = xtoa ((GFC_UINTEGER_LARGEST) (intptr_t) trace[i], addr_buf[i],
sizeof (addr_buf[i]));
/* Don't output an error message if something goes wrong, we'll simply
fall back to the pstack and glibc backtraces. */
if (pipe (f) != 0)
break;
if ((pid = fork ()) == -1)
break;
if (pid == 0)
{
/* Child process. */
#define NUM_FIXEDARGS 5
char *arg[DEPTH+NUM_FIXEDARGS+1];
close (f[0]);
close (STDIN_FILENO);
close (STDERR_FILENO);
if (dup2 (f[1], STDOUT_FILENO) == -1)
_exit (0);
close (f[1]);
arg[0] = (char *) "addr2line";
arg[1] = (char *) "-e";
arg[2] = full_exe_path ();
arg[3] = (char *) "-f";
arg[4] = (char *) "-s";
for (i = 0; i < depth; i++)
arg[NUM_FIXEDARGS+i] = (char *) addr[i];
arg[NUM_FIXEDARGS+depth] = NULL;
execvp (arg[0], arg);
_exit (0);
#undef NUM_FIXEDARGS
}
/* Father process. */
close (f[1]);
wait (NULL);
output = fdopen (f[0], "r");
i = -1;
if (fgets (func, sizeof(func), output))
{
st_printf ("\nBacktrace for this error:\n");
do
{
if (! fgets (file, sizeof(file), output))
goto fallback;
i++;
for (p = func; *p != '\n' && *p != '\r'; p++)
;
*p = '\0';
/* Try to recognize the internal libgfortran functions. */
if (strncasecmp (func, "*_gfortran", 10) == 0
|| strncasecmp (func, "_gfortran", 9) == 0
|| strcmp (func, "main") == 0 || strcmp (func, "_start") == 0
|| strcmp (func, "_gfortrani_handler") == 0)
continue;
if (local_strcasestr (str[i], "libgfortran.so") != NULL
|| local_strcasestr (str[i], "libgfortran.dylib") != NULL
|| local_strcasestr (str[i], "libgfortran.a") != NULL)
continue;
/* If we only have the address, use the glibc backtrace. */
if (func[0] == '?' && func[1] == '?' && file[0] == '?'
&& file[1] == '?')
{
st_printf (" + %s\n", str[i]);
continue;
}
/* Extract the line number. */
for (end = NULL, p = file; *p; p++)
if (*p == ':')
end = p;
if (end != NULL)
{
*end = '\0';
line = atoi (++end);
}
else
line = -1;
if (strcmp (func, "MAIN__") == 0)
st_printf (" + in the main program\n");
else
st_printf (" + function %s (0x%s)\n", func, addr[i]);
if (line <= 0 && strcmp (file, "??") == 0)
continue;
if (line <= 0)
st_printf (" from file %s\n", file);
else
st_printf (" at line %d of file %s\n", line, file);
}
while (fgets (func, sizeof(func), output));
free (str);
return;
fallback:
st_printf ("** Something went wrong while running addr2line. **\n"
"** Falling back to a simpler backtrace scheme. **\n");
}
}
while (0);
#undef DEPTH
#undef BUFSIZE
#endif
#endif
#if CAN_FORK && defined(HAVE_GETPPID)
/* Try to call pstack. */
do
{
/* Local variables. */
int pid;
/* Don't output an error message if something goes wrong, we'll simply
fall back to the pstack and glibc backtraces. */
if ((pid = fork ()) == -1)
break;
if (pid == 0)
{
/* Child process. */
#define NUM_ARGS 2
char *arg[NUM_ARGS+1];
char buf[20];
st_printf ("\nBacktrace for this error:\n");
arg[0] = (char *) "pstack";
#ifdef HAVE_SNPRINTF
snprintf (buf, sizeof(buf), "%d", (int) getppid ());
#else
sprintf (buf, "%d", (int) getppid ());
#endif
arg[1] = buf;
arg[2] = NULL;
execvp (arg[0], arg);
#undef NUM_ARGS
/* pstack didn't work, so we fall back to dumping the glibc
backtrace if we can. */
#if GLIBC_BACKTRACE
dump_glibc_backtrace (depth, str);
#else
st_printf (" unable to produce a backtrace, sorry!\n");
#endif
_exit (0);
}
/* Father process. */
wait (NULL);
return;
}
while(0);
#endif
#if GLIBC_BACKTRACE
/* Fallback to the glibc backtrace. */
st_printf ("\nBacktrace for this error:\n");
dump_glibc_backtrace (depth, str);
#endif
}
void
show_backtrace (void)
{
#if GLIBC_BACKTRACE
#define DEPTH 50
#define BUFSIZE 1024
void *trace[DEPTH];
int depth;
depth = backtrace (trace, DEPTH);
if (depth <= 0)
return;
#if CAN_PIPE
if (addr2line_path == NULL)
goto fallback_noerr;
/* We attempt to extract file and line information from addr2line. */
do
{
/* Local variables. */
int f[2], pid, bt[2], inp[2];
char addr_buf[GFC_XTOA_BUF_SIZE], func[BUFSIZE], file[BUFSIZE];
char *p;
/* Don't output an error message if something goes wrong, we'll simply
fall back to the pstack and glibc backtraces. */
if (pipe (f) != 0)
break;
if (pipe (inp) != 0)
break;
if ((pid = fork ()) == -1)
break;
if (pid == 0)
{
/* Child process. */
#define NUM_FIXEDARGS 7
char *arg[NUM_FIXEDARGS];
char *newenv[] = { NULL };
close (f[0]);
close (inp[1]);
if (dup2 (inp[0], STDIN_FILENO) == -1)
_exit (1);
close (inp[0]);
close (STDERR_FILENO);
if (dup2 (f[1], STDOUT_FILENO) == -1)
_exit (1);
close (f[1]);
arg[0] = addr2line_path;
arg[1] = (char *) "-e";
arg[2] = full_exe_path ();
arg[3] = (char *) "-f";
arg[4] = (char *) "-s";
arg[5] = (char *) "-C";
arg[6] = NULL;
execve (addr2line_path, arg, newenv);
_exit (1);
#undef NUM_FIXEDARGS
}
/* Father process. */
close (f[1]);
close (inp[0]);
if (pipe (bt) != 0)
break;
backtrace_symbols_fd (trace, depth, bt[1]);
close (bt[1]);
estr_write ("\nBacktrace for this error:\n");
for (int j = 0; j < depth; j++)
{
const char *addr = gfc_xtoa
((GFC_UINTEGER_LARGEST) (intptr_t) trace[j],
addr_buf, sizeof (addr_buf));
write (inp[1], addr, strlen (addr));
write (inp[1], "\n", 1);
if (! fd_gets (func, sizeof(func), f[0]))
goto fallback;
if (! fd_gets (file, sizeof(file), f[0]))
goto fallback;
for (p = func; *p != '\n' && *p != '\r'; p++)
;
*p = '\0';
/* If we only have the address, use the glibc backtrace. */
if (func[0] == '?' && func[1] == '?' && file[0] == '?'
&& file[1] == '?')
{
bt_header (j);
while (1)
{
char bc;
ssize_t nread = read (bt[0], &bc, 1);
if (nread != 1 || bc == '\n')
break;
write (STDERR_FILENO, &bc, 1);
}
estr_write ("\n");
continue;
}
else
{
/* Forward to the next entry in the backtrace. */
while (1)
{
char bc;
ssize_t nread = read (bt[0], &bc, 1);
if (nread != 1 || bc == '\n')
break;
}
}
/* _start is a setup routine that calls main(), and main() is
the frontend routine that calls some setup stuff and then
calls MAIN__, so at this point we should stop. */
if (strcmp (func, "_start") == 0 || strcmp (func, "main") == 0)
break;
bt_header (j);
estr_write (full_exe_path ());
estr_write ("[0x");
estr_write (addr);
estr_write ("] in ");
estr_write (func);
if (strncmp (file, "??", 2) == 0)
estr_write ("\n");
else
{
estr_write (" at ");
estr_write (file);
}
} /* Loop over each hex address. */
close (inp[1]);
close (bt[0]);
wait (NULL);
return;
fallback:
estr_write ("** Something went wrong while running addr2line. **\n"
"** Falling back to a simpler backtrace scheme. **\n");
}
while (0);
#undef DEPTH
#undef BUFSIZE
#endif /* CAN_PIPE */
fallback_noerr:
/* Fallback to the glibc backtrace. */
estr_write ("\nBacktrace for this error:\n");
backtrace_symbols_fd (trace, depth, STDERR_FILENO);
return;
#elif defined(CAN_FORK) && defined(HAVE_GETPPID)
/* Try to call pstack. */
do
{
/* Local variables. */
int pid;
/* Don't output an error message if something goes wrong, we'll simply
fall back to the pstack and glibc backtraces. */
if ((pid = fork ()) == -1)
break;
if (pid == 0)
{
/* Child process. */
#define NUM_ARGS 2
char *arg[NUM_ARGS+1];
char buf[20];
estr_write ("\nBacktrace for this error:\n");
arg[0] = (char *) "pstack";
snprintf (buf, sizeof(buf), "%d", (int) getppid ());
arg[1] = buf;
arg[2] = NULL;
execvp (arg[0], arg);
#undef NUM_ARGS
/* pstack didn't work. */
estr_write (" unable to produce a backtrace, sorry!\n");
_exit (1);
}
/* Father process. */
wait (NULL);
return;
}
while(0);
#else
estr_write ("\nBacktrace not yet available on this platform, sorry!\n");
#endif
}
