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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /debug/segfault.c
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
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(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'debug/segfault.c')
-rw-r--r--debug/segfault.c214
1 files changed, 0 insertions, 214 deletions
diff --git a/debug/segfault.c b/debug/segfault.c
deleted file mode 100644
index f141fff..0000000
--- a/debug/segfault.c
+++ /dev/null
@@ -1,214 +0,0 @@
-/* Catch segmentation faults and print backtrace.
- Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004
- Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
-
-#include <alloca.h>
-#include <ctype.h>
-#include <errno.h>
-#include <execinfo.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <stdio-common/_itoa.h>
-#include <ldsodefs.h>
-
-#include <bp-checks.h>
-
-/* This file defines macros to access the content of the sigcontext element
- passed up by the signal handler. */
-#include <sigcontextinfo.h>
-
-/* Get code to possibly dump the content of all registers. */
-#include <register-dump.h>
-
-/* We'll use tis a lot. */
-#define WRITE_STRING(s) write (fd, s, strlen (s))
-
-/* Name of the output file. */
-static const char *fname;
-
-
-/* We better should not use `strerror' since it can call far too many
- other functions which might fail. Do it here ourselves. */
-static void
-write_strsignal (int fd, int signal)
-{
- if (signal < 0 || signal >= _NSIG || _sys_siglist[signal] == NULL)
- {
- char buf[30];
- char *ptr = _itoa_word (signal, &buf[sizeof (buf)], 10, 0);
- WRITE_STRING ("signal ");
- write (fd, buf, &buf[sizeof (buf)] - ptr);
- }
- else
- WRITE_STRING (_sys_siglist[signal]);
-}
-
-
-/* This function is called when a segmentation fault is caught. The system
- is in an instable state now. This means especially that malloc() might
- not work anymore. */
-static void
-catch_segfault (int signal, SIGCONTEXT ctx)
-{
- int fd, cnt, i;
- void **arr;
- struct sigaction sa;
- uintptr_t pc;
-
- /* This is the name of the file we are writing to. If none is given
- or we cannot write to this file write to stderr. */
- fd = 2;
- if (fname != NULL)
- {
- fd = open (fname, O_TRUNC | O_WRONLY | O_CREAT, 0666);
- if (fd == -1)
- fd = 2;
- }
-
- WRITE_STRING ("*** ");
- write_strsignal (fd, signal);
- WRITE_STRING ("\n");
-
-#ifdef REGISTER_DUMP
- REGISTER_DUMP;
-#endif
-
- WRITE_STRING ("\nBacktrace:\n");
-
- /* Get the backtrace. */
- arr = alloca (256 * sizeof (void *));
- cnt = backtrace (arr, 256);
-
- /* Now try to locate the PC from signal context in the backtrace.
- Normally it will be found at arr[2], but it might appear later
- if there were some signal handler wrappers. Allow a few bytes
- difference to cope with as many arches as possible. */
- pc = (uintptr_t) GET_PC (ctx);
- for (i = 0; i < cnt; ++i)
- if ((uintptr_t) arr[i] >= pc - 16 && (uintptr_t) arr[i] <= pc + 16)
- break;
-
- /* If we haven't found it, better dump full backtrace even including
- the signal handler frames instead of not dumping anything. */
- if (i == cnt)
- i = 0;
-
- /* Now generate nicely formatted output. */
- __backtrace_symbols_fd (arr + i, cnt - i, fd);
-
-#ifdef HAVE_PROC_SELF
- /* Now the link map. */
- int mapfd = open ("/proc/self/maps", O_RDONLY);
- if (mapfd != -1)
- {
- write (fd, "\nMemory map:\n\n", 14);
-
- char buf[256];
- ssize_t n;
-
- while ((n = TEMP_FAILURE_RETRY (read (mapfd, buf, sizeof (buf)))) > 0)
- TEMP_FAILURE_RETRY (write (fd, buf, n));
-
- close (mapfd);
- }
-#endif
-
- /* Pass on the signal (so that a core file is produced). */
- sa.sa_handler = SIG_DFL;
- sigemptyset (&sa.sa_mask);
- sa.sa_flags = 0;
- sigaction (signal, &sa, NULL);
- raise (signal);
-}
-
-
-static void
-__attribute__ ((constructor))
-install_handler (void)
-{
- struct sigaction sa;
- const char *sigs = getenv ("SEGFAULT_SIGNALS");
- const char *name;
-
- sa.sa_handler = (void *) catch_segfault;
- sigemptyset (&sa.sa_mask);
- sa.sa_flags = SA_RESTART;
-
- /* Maybe we are expected to use an alternative stack. */
- if (getenv ("SEGFAULT_USE_ALTSTACK") != 0)
- {
- void *stack_mem = malloc (2 * SIGSTKSZ);
- struct sigaltstack ss;
-
- if (stack_mem != NULL)
- {
- ss.ss_sp = stack_mem;
- ss.ss_flags = 0;
- ss.ss_size = 2 * SIGSTKSZ;
-
- if (sigaltstack (&ss, NULL) == 0)
- sa.sa_flags |= SA_ONSTACK;
- }
- }
-
- if (sigs == NULL)
- sigaction (SIGSEGV, &sa, NULL);
- else if (sigs[0] == '\0')
- /* Do not do anything. */
- return;
- else
- {
- const char *where;
- int all = __strcasecmp (sigs, "all") == 0;
-
-#define INSTALL_FOR_SIG(sig, name) \
- where = __strcasestr (sigs, name); \
- if (all || (where != NULL \
- && (where == sigs || !isalnum (where[-1])) \
- && !isalnum (where[sizeof (name) - 1]))) \
- sigaction (sig, &sa, NULL);
-
- INSTALL_FOR_SIG (SIGSEGV, "segv");
- INSTALL_FOR_SIG (SIGILL, "ill");
-#ifdef SIGBUS
- INSTALL_FOR_SIG (SIGBUS, "bus");
-#endif
-#ifdef SIGSTKFLT
- INSTALL_FOR_SIG (SIGSTKFLT, "stkflt");
-#endif
- INSTALL_FOR_SIG (SIGABRT, "abrt");
- INSTALL_FOR_SIG (SIGFPE, "fpe");
- }
-
- /* Preserve the output file name if there is any given. */
- name = getenv ("SEGFAULT_OUTPUT_NAME");
- if (name != NULL && name[0] != '\0')
- {
- int ret = access (name, R_OK | W_OK);
-
- if (ret == 0 || (ret == -1 && errno == ENOENT))
- fname = __strdup (name);
- }
-}