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authorSergei Golubchik <sergii@pisem.net>2012-01-16 20:16:35 +0100
committerSergei Golubchik <sergii@pisem.net>2012-01-16 20:16:35 +0100
commit38e3ae155db08ab2e9e5c267f05f89bec0542b33 (patch)
tree7289bbef1ba3f495aa5c7cdb7d0a3f993a5bbc80 /sql/signal_handler.cc
parentc56483d972d023105fbcb0f47af0042ee092657c (diff)
parented1ba992c1d3c3ecbe6a2769c51ceb5d27606d3b (diff)
downloadmariadb-git-38e3ae155db08ab2e9e5c267f05f89bec0542b33.tar.gz
mysql-5.5 merge
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+/* Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+
+ This program 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; version 2 of the License.
+
+ This program 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, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02111-1307 USA */
+
+#include "my_global.h"
+#include <signal.h>
+
+//#include "sys_vars.h"
+#include <keycache.h>
+#include "mysqld.h"
+#include "sql_class.h"
+#include "my_stacktrace.h"
+
+#ifdef __WIN__
+#include <crtdbg.h>
+#define SIGNAL_FMT "exception 0x%x"
+#else
+#define SIGNAL_FMT "signal %d"
+#endif
+
+/*
+ We are handling signals in this file.
+ Any global variables we read should be 'volatile sig_atomic_t'
+ to guarantee that we read some consistent value.
+ */
+static volatile sig_atomic_t segfaulted= 0;
+extern ulong max_used_connections;
+extern volatile sig_atomic_t calling_initgroups;
+#ifdef HAVE_NPTL
+extern volatile sig_atomic_t ld_assume_kernel_is_set;
+#endif
+
+extern const char *optimizer_switch_names[];
+
+/**
+ * Handler for fatal signals
+ *
+ * Fatal events (seg.fault, bus error etc.) will trigger
+ * this signal handler. The handler will try to dump relevant
+ * debugging information to stderr and dump a core image.
+ *
+ * Signal handlers can only use a set of 'safe' system calls
+ * and library functions. A list of safe calls in POSIX systems
+ * are available at:
+ * http://pubs.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_04.html
+ * For MS Windows, guidelines are available at:
+ * http://msdn.microsoft.com/en-us/library/xdkz3x12(v=vs.71).aspx
+ *
+ * @param sig Signal number
+*/
+extern "C" sig_handler handle_fatal_signal(int sig)
+{
+ if (segfaulted)
+ {
+ my_safe_printf_stderr("Fatal " SIGNAL_FMT " while backtracing\n", sig);
+ _exit(1); /* Quit without running destructors */
+ }
+
+ segfaulted = 1;
+
+#ifdef __WIN__
+ SYSTEMTIME utc_time;
+ GetSystemTime(&utc_time);
+ const long hrs= utc_time.wHour;
+ const long mins= utc_time.wMinute;
+ const long secs= utc_time.wSecond;
+#else
+ /* Using time() instead of my_time() to avoid looping */
+ const time_t curr_time= time(NULL);
+ /* Calculate time of day */
+ const long tmins = curr_time / 60;
+ const long thrs = tmins / 60;
+ const long hrs = thrs % 24;
+ const long mins = tmins % 60;
+ const long secs = curr_time % 60;
+#endif
+
+ char hrs_buf[3]= "00";
+ char mins_buf[3]= "00";
+ char secs_buf[3]= "00";
+ my_safe_itoa(10, hrs, &hrs_buf[2]);
+ my_safe_itoa(10, mins, &mins_buf[2]);
+ my_safe_itoa(10, secs, &secs_buf[2]);
+
+ my_safe_printf_stderr("%s:%s:%s UTC - mysqld got " SIGNAL_FMT " ;\n",
+ hrs_buf, mins_buf, secs_buf, sig);
+
+ my_safe_printf_stderr("%s",
+ "This could be because you hit a bug. It is also possible that this binary\n"
+ "or one of the libraries it was linked against is corrupt, improperly built,\n"
+ "or misconfigured. This error can also be caused by malfunctioning hardware.\n");
+
+ my_safe_printf_stderr("%s",
+ "We will try our best to scrape up some info that will hopefully help\n"
+ "diagnose the problem, but since we have already crashed, \n"
+ "something is definitely wrong and this may fail.\n\n");
+
+ my_safe_printf_stderr("Server version: %s\n", server_version);
+
+ my_safe_printf_stderr("key_buffer_size=%lu\n",
+ (ulong) dflt_key_cache->key_cache_mem_size);
+
+ my_safe_printf_stderr("read_buffer_size=%ld\n",
+ (long) global_system_variables.read_buff_size);
+
+ my_safe_printf_stderr("max_used_connections=%lu\n",
+ (ulong) max_used_connections);
+
+ my_safe_printf_stderr("max_threads=%u\n",
+ (uint) thread_scheduler->max_threads +
+ (uint) extra_max_connections);
+
+ my_safe_printf_stderr("thread_count=%u\n", (uint) thread_count);
+
+ my_safe_printf_stderr("It is possible that mysqld could use up to \n"
+ "key_buffer_size + "
+ "(read_buffer_size + sort_buffer_size)*max_threads = "
+ "%lu K bytes of memory\n",
+ (ulong)(dflt_key_cache->key_cache_mem_size +
+ (global_system_variables.read_buff_size +
+ global_system_variables.sortbuff_size) *
+ (thread_scheduler->max_threads + extra_max_connections) +
+ (max_connections + extra_max_connections)* sizeof(THD)) / 1024);
+
+ my_safe_printf_stderr("%s",
+ "Hope that's ok; if not, decrease some variables in the equation.\n\n");
+
+#if defined(HAVE_LINUXTHREADS)
+ if (sizeof(char*) == 4 && thread_count > UNSAFE_DEFAULT_LINUX_THREADS)
+ {
+ my_safe_printf_stderr(
+ "You seem to be running 32-bit Linux and have "
+ "%d concurrent connections.\n"
+ "If you have not changed STACK_SIZE in LinuxThreads "
+ "and built the binary \n"
+ "yourself, LinuxThreads is quite likely to steal "
+ "a part of the global heap for\n"
+ "the thread stack. Please read "
+ "http://dev.mysql.com/doc/mysql/en/linux-installation.html\n\n"
+ thread_count);
+ }
+#endif /* HAVE_LINUXTHREADS */
+
+#ifdef HAVE_STACKTRACE
+ THD *thd=current_thd;
+
+ if (opt_stack_trace)
+ {
+ my_safe_printf_stderr("Thread pointer: 0x%p\n", thd);
+ my_safe_printf_stderr("%s",
+ "Attempting backtrace. You can use the following "
+ "information to find out\n"
+ "where mysqld died. If you see no messages after this, something went\n"
+ "terribly wrong...\n");
+ my_print_stacktrace(thd ? (uchar*) thd->thread_stack : NULL,
+ my_thread_stack_size);
+ }
+ if (thd)
+ {
+ const char *kreason= "UNKNOWN";
+ switch (thd->killed) {
+ case NOT_KILLED:
+ case KILL_HARD_BIT:
+ kreason= "NOT_KILLED";
+ break;
+ case KILL_BAD_DATA:
+ case KILL_BAD_DATA_HARD:
+ kreason= "KILL_BAD_DATA";
+ break;
+ case KILL_CONNECTION:
+ case KILL_CONNECTION_HARD:
+ kreason= "KILL_CONNECTION";
+ break;
+ case KILL_QUERY:
+ case KILL_QUERY_HARD:
+ kreason= "KILL_QUERY";
+ break;
+ case KILL_SYSTEM_THREAD:
+ case KILL_SYSTEM_THREAD_HARD:
+ kreason= "KILL_SYSTEM_THREAD";
+ break;
+ case KILL_SERVER:
+ case KILL_SERVER_HARD:
+ kreason= "KILL_SERVER";
+ break;
+ }
+ my_safe_printf_stderr("%s", "\n"
+ "Trying to get some variables.\n"
+ "Some pointers may be invalid and cause the dump to abort.\n");
+
+ my_safe_printf_stderr("Query (%p): ", thd->query());
+ my_safe_print_str(thd->query(), min(65536U, thd->query_length()));
+ my_safe_printf_stderr("\nConnection ID (thread ID): %lu\n",
+ (ulong) thd->thread_id);
+ my_safe_printf_stderr("Status: %s\n\n", kreason);
+ my_safe_printf_stderr("%s", "Optimizer switch: ");
+ ulonglong optsw= thd->variables.optimizer_switch;
+ for (uint i= 0; optimizer_switch_names[i+1]; i++, optsw >>= 1)
+ {
+ if (i)
+ my_safe_printf_stderr("%s", ",");
+ my_safe_printf_stderr("%s=%s",
+ optimizer_switch_names[i], optsw & 1 ? "on" : "off");
+ }
+ my_safe_printf_stderr("%s", "\n\n");
+ }
+ my_safe_printf_stderr("%s",
+ "The manual page at "
+ "http://dev.mysql.com/doc/mysql/en/crashing.html contains\n"
+ "information that should help you find out what is causing the crash.\n");
+
+#endif /* HAVE_STACKTRACE */
+
+#ifdef HAVE_INITGROUPS
+ if (calling_initgroups)
+ {
+ my_safe_printf_stderr("%s", "\n"
+ "This crash occured while the server was calling initgroups(). This is\n"
+ "often due to the use of a mysqld that is statically linked against \n"
+ "glibc and configured to use LDAP in /etc/nsswitch.conf.\n"
+ "You will need to either upgrade to a version of glibc that does not\n"
+ "have this problem (2.3.4 or later when used with nscd),\n"
+ "disable LDAP in your nsswitch.conf, or use a "
+ "mysqld that is not statically linked.\n");
+ }
+#endif
+
+#ifdef HAVE_NPTL
+ if (thd_lib_detected == THD_LIB_LT && !ld_assume_kernel_is_set)
+ {
+ my_safe_printf_stderr("%s",
+ "You are running a statically-linked LinuxThreads binary on an NPTL\n"
+ "system. This can result in crashes on some distributions due to "
+ "LT/NPTL conflicts.\n"
+ "You should either build a dynamically-linked binary, "
+ "or force LinuxThreads\n"
+ "to be used with the LD_ASSUME_KERNEL environment variable.\n"
+ "Please consult the documentation for your distribution "
+ "on how to do that.\n");
+ }
+#endif
+
+ if (locked_in_memory)
+ {
+ my_safe_printf_stderr("%s", "\n"
+ "The \"--memlock\" argument, which was enabled, "
+ "uses system calls that are\n"
+ "unreliable and unstable on some operating systems and "
+ "operating-system versions (notably, some versions of Linux).\n"
+ "This crash could be due to use of those buggy OS calls.\n"
+ "You should consider whether you really need the "
+ "\"--memlock\" parameter and/or consult the OS distributer about "
+ "\"mlockall\" bugs.\n");
+ }
+
+#ifdef HAVE_WRITE_CORE
+ if (test_flags & TEST_CORE_ON_SIGNAL)
+ {
+ my_safe_printf_stderr("%s", "Writing a core file\n");
+ my_write_core(sig);
+ }
+#endif
+
+#ifndef __WIN__
+ /*
+ Quit, without running destructors (etc.)
+ On Windows, do not terminate, but pass control to exception filter.
+ */
+ _exit(1); // Using _exit(), since exit() is not async signal safe
+#endif
+}