-/* Copyright (C) 2006, 2007, 2009, 2011 Free Software Foundation, Inc.
+/* Copyright (C) 2006-2018 Free Software Foundation, Inc.
Contributed by François-Xavier Coudert
This file is part of the GNU Fortran runtime library (libgfortran).
#include "libgfortran.h"
-#include <string.h>
-
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
+#include <gthr.h>
-#ifdef HAVE_INTTYPES_H
-#include <inttypes.h>
-#endif
+#include <string.h>
+#include <errno.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
-#ifdef HAVE_EXECINFO_H
-#include <execinfo.h>
-#endif
+#include "backtrace-supported.h"
+#include "backtrace.h"
-#ifdef HAVE_SYS_WAIT_H
-#include <sys/wait.h>
-#endif
-
-#include <ctype.h>
+/* Store our own state while backtracing. */
+struct mystate
+{
+ int frame;
+ bool try_simple;
+ bool in_signal_handler;
+};
-/* Macros for common sets of capabilities: can we fork and exec, can
- we use glibc-style backtrace functions, and can we use pipes. */
-#define CAN_FORK (defined(HAVE_FORK) && defined(HAVE_EXECVP) \
- && defined(HAVE_WAIT))
-#define GLIBC_BACKTRACE (defined(HAVE_BACKTRACE) \
- && defined(HAVE_BACKTRACE_SYMBOLS))
-#define CAN_PIPE (CAN_FORK && defined(HAVE_PIPE) \
- && defined(HAVE_DUP2) && defined(HAVE_FDOPEN) \
- && defined(HAVE_CLOSE))
+/* Does a function name have "_gfortran_" or "_gfortrani_" prefix, possibly
+ with additional underscore(s) at the beginning? Cannot use strncmp()
+ because we might be called from a signal handler. */
-#if GLIBC_BACKTRACE && CAN_PIPE
-static char *
-local_strcasestr (const char *s1, const char *s2)
+static int
+has_gfortran_prefix (const char *s)
{
-#ifdef HAVE_STRCASESTR
- return strcasestr (s1, s2);
-#else
+ if (!s)
+ return 0;
- const char *p = s1;
- const size_t len = strlen (s2);
- const char u = *s2, v = isupper((int) *s2) ? tolower((int) *s2)
- : (islower((int) *s2) ? toupper((int) *s2)
- : *s2);
+ while (*s == '_')
+ s++;
- while (1)
- {
- while (*p != u && *p != v && *p)
- p++;
- if (*p == 0)
- return NULL;
- if (strncasecmp (p, s2, len) == 0)
- return (char *)p;
- }
-#endif
+ return (s[0] == 'g' && s[1] == 'f' && s[2] == 'o' && s[3] == 'r'
+ && s[4] == 't' && s[5] == 'r' && s[6] == 'a' && s[7] == 'n'
+ && (s[8] == '_' || (s[8] == 'i' && s[9] == '_')));
}
-#endif
-
-#if GLIBC_BACKTRACE
static void
-dump_glibc_backtrace (int depth, char *str[])
+error_callback (void *data, const char *msg, int errnum)
{
- int i;
+ struct mystate *state = (struct mystate *) data;
+#define ERRHDR "\nCould not print backtrace: "
- for (i = 0; i < depth; i++)
+ if (errnum < 0)
{
- estr_write (" + ");
- estr_write (str[i]);
+ state->try_simple = true;
+ return;
+ }
+ else if (errnum == 0)
+ {
+ estr_write (ERRHDR);
+ estr_write (msg);
estr_write ("\n");
}
+ else
+ {
+ char errbuf[256];
+ if (state->in_signal_handler)
+ {
+ estr_write (ERRHDR);
+ estr_write (msg);
+ estr_write (", errno: ");
+ const char *p = gfc_itoa (errnum, errbuf, sizeof (errbuf));
+ estr_write (p);
+ estr_write ("\n");
+ }
+ else
+ st_printf (ERRHDR "%s: %s\n", msg,
+ gf_strerror (errnum, errbuf, sizeof (errbuf)));
+ }
+}
- free (str);
+static int
+simple_callback (void *data, uintptr_t pc)
+{
+ struct mystate *state = (struct mystate *) data;
+ st_printf ("#%d 0x%lx\n", state->frame, (unsigned long) pc);
+ (state->frame)++;
+ return 0;
}
-#endif
-/* show_backtrace displays the backtrace, currently obtained by means of
- the glibc backtrace* functions. */
-void
-show_backtrace (void)
+static int
+full_callback (void *data, uintptr_t pc, const char *filename,
+ int lineno, const char *function)
{
-#if GLIBC_BACKTRACE
+ struct mystate *state = (struct mystate *) data;
-#define DEPTH 50
-#define BUFSIZE 1024
+ if (has_gfortran_prefix (function))
+ return 0;
- void *trace[DEPTH];
- char **str;
- int depth;
+ st_printf ("#%d 0x%lx in %s\n", state->frame,
+ (unsigned long) pc, function == NULL ? "???" : function);
+ if (filename || lineno != 0)
+ st_printf ("\tat %s:%d\n", filename == NULL ? "???" : filename, lineno);
+ (state->frame)++;
- depth = backtrace (trace, DEPTH);
- if (depth <= 0)
- return;
+ if (function != NULL && strcmp (function, "main") == 0)
+ return 1;
- str = backtrace_symbols (trace, depth);
+ return 0;
+}
-#if CAN_PIPE
-#ifndef STDIN_FILENO
-#define STDIN_FILENO 0
-#endif
+/* Display the backtrace. */
-#ifndef STDOUT_FILENO
-#define STDOUT_FILENO 1
-#endif
+void
+show_backtrace (bool in_signal_handler)
+{
+ struct backtrace_state *lbstate;
+ struct mystate state = { 0, false, in_signal_handler };
+
+ lbstate = backtrace_create_state (NULL, __gthread_active_p (),
+ error_callback, NULL);
-#ifndef STDERR_FILENO
-#define STDERR_FILENO 2
-#endif
+ if (lbstate == NULL)
+ return;
- /* 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] = gfc_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))
- {
- estr_write ("\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_backtrace_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] == '?')
- {
- estr_write (" + ");
- estr_write (str[i]);
- estr_write ("\n");
- 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)
- estr_write (" + in the main program\n");
- else
- {
- estr_write (" + function ");
- estr_write (func);
- estr_write (" (0x");
- estr_write (addr[i]);
- estr_write (")\n");
- }
-
- if (line <= 0 && strcmp (file, "??") == 0)
- continue;
-
- if (line <= 0)
- {
- estr_write (" from file ");
- estr_write (file);
- estr_write ("\n");
- }
- else
- st_printf (" at line %d of file %s\n", line, file);
- }
- while (fgets (func, sizeof(func), output));
-
- free (str);
- return;
-
-fallback:
- estr_write ("** Something went wrong while running addr2line. **\n"
- "** Falling back to a simpler backtrace scheme. **\n");
- }
+ if (!BACKTRACE_SUPPORTED || (in_signal_handler && BACKTRACE_USES_MALLOC))
+ {
+ /* If symbolic backtrace is not supported on this target, or would
+ require malloc() and we are in a signal handler, go with a
+ simple backtrace. */
+
+ backtrace_simple (lbstate, 0, simple_callback, error_callback, &state);
}
- while (0);
+ else
+ {
+ /* libbacktrace uses mmap, which is safe to call from a signal handler
+ (in practice, if not in theory). Thus we can generate a symbolic
+ backtrace, if debug symbols are available. */
-#undef DEPTH
-#undef BUFSIZE
+ backtrace_full (lbstate, 0, full_callback, error_callback, &state);
+ if (state.try_simple)
+ backtrace_simple (lbstate, 0, simple_callback, error_callback, &state);
+ }
+}
-#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];
-
- 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, so we fall back to dumping the glibc
- backtrace if we can. */
-#if GLIBC_BACKTRACE
- dump_glibc_backtrace (depth, str);
-#else
- estr_write (" unable to produce a backtrace, sorry!\n");
-#endif
- _exit (0);
- }
+/* Function called by the front-end translating the BACKTRACE intrinsic. */
- /* Father process. */
- wait (NULL);
- return;
- }
- while(0);
-#endif
+extern void backtrace (void);
+export_proto (backtrace);
-#if GLIBC_BACKTRACE
- /* Fallback to the glibc backtrace. */
- estr_write ("\nBacktrace for this error:\n");
- dump_glibc_backtrace (depth, str);
- return;
-#endif
- estr_write ("\nBacktrace not yet available on this platform, sorry!\n");
+void
+backtrace (void)
+{
+ show_backtrace (false);
}
+