auroramon.patch

diff -urN MaxScale-maxscale-2.0.1.orig/server/include/alloc.h MaxScale-maxscale-2.0.1/server/include/alloc.h
--- MaxScale-maxscale-2.0.1.orig/server/include/alloc.h	1970-01-01 00:00:00.000000000 +0000
+++ MaxScale-maxscale-2.0.1/server/include/alloc.h	2016-11-08 11:50:27.787027160 +0000
@@ -0,0 +1,79 @@
+#pragma once
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include <maxscale/cdefs.h>
+#include <stdlib.h>
+#include <string.h>
+
+MXS_BEGIN_DECLS
+
+/*
+ * NOTE: Do not use these functions directly, use the macros below.
+ */
+
+// "caller" arg temporarily disabled so that existing code
+// using the previous version of mxs_alloc etc. will continue
+// to compile.
+void *mxs_malloc(size_t size/*, const char *caller*/);
+void *mxs_calloc(size_t nmemb, size_t size/*, const char *caller*/);
+void *mxs_realloc(void *ptr, size_t size/*, const char *caller*/);
+void mxs_free(void *ptr/*, const char *caller*/);
+
+char *mxs_strdup(const char *s/*, const char *caller*/);
+char *mxs_strndup(const char *s, size_t n/*, const char *caller*/);
+
+char *mxs_strdup_a(const char *s/*, const char *caller*/);
+char *mxs_strndup_a(const char *s, size_t n/*, const char *caller*/);
+
+
+/*
+ * NOTE: USE these macros instead of the functions above.
+ */
+#define MXS_MALLOC(size)         mxs_malloc(size/*, __func__*/)
+#define MXS_CALLOC(nmemb, size)  mxs_calloc(nmemb, size/*, __func__*/)
+#define MXS_REALLOC(ptr, size)   mxs_realloc(ptr, size/*, __func__*/)
+#define MXS_FREE(ptr)            mxs_free(ptr/*, __func__*/)
+
+#define MXS_STRDUP(s)            mxs_strdup(s/*, __func__*/)
+#define MXS_STRNDUP(s, n)        mxs_strndup(s, n/*, __func__*/)
+
+#define MXS_STRDUP_A(s)          mxs_strdup_a(s/*, __func__*/)
+#define MXS_STRNDUP_A(s, n)      mxs_strndup_a(s, n/*, __func__*/)
+
+
+/**
+ * @brief Abort the process if the pointer is NULL.
+ *
+ * To be used in circumstances where a memory allocation failure
+ * cannot - currently - be dealt with properly.
+ */
+#define MXS_ABORT_IF_NULL(p) do { if (!p) { abort(); } } while (false)
+
+/**
+ * @brief Abort the process if the provided value is non-zero.
+ *
+ * To be used in circumstances where a memory allocation or other
+ * fatal error cannot - currently - be dealt with properly.
+ */
+#define MXS_ABORT_IF_TRUE(b) do { if (b) { abort(); } } while (false)
+
+/**
+ * @brief Abort the process if the provided value is zero.
+ *
+ * To be used in circumstances where a memory allocation or other
+ * fatal error cannot - currently - be dealt with properly.
+ */
+#define MXS_ABORT_IF_FALSE(b) do { if (!b) { abort(); } } while (false)
+
+MXS_END_DECLS
diff -urN MaxScale-maxscale-2.0.1.orig/server/include/maxscale/cdefs.h MaxScale-maxscale-2.0.1/server/include/maxscale/cdefs.h
--- MaxScale-maxscale-2.0.1.orig/server/include/maxscale/cdefs.h	1970-01-01 00:00:00.000000000 +0000
+++ MaxScale-maxscale-2.0.1/server/include/maxscale/cdefs.h	2016-11-08 11:52:13.864810227 +0000
@@ -0,0 +1,76 @@
+#pragma once
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+/**
+ * @file cdefs.h
+ *
+ * This file has several purposes.
+ *
+ * - Its purpose is the same as that of x86_64-linux-gnu/sys/cdefs.h, that is,
+ *   it defines things that are dependent upon the compilation environment.
+ * - Since this *must* be included as the very first header by all other MaxScale
+ *   headers, it allows you to redfine things globally, should that be necessary,
+ *   for instance, when debugging something.
+ * - Global constants applicable across the line can be defined here.
+ */
+
+#ifdef	__cplusplus
+# define MXS_BEGIN_DECLS extern "C" {
+# define MXS_END_DECLS	 }
+#else
+# define MXS_BEGIN_DECLS
+# define MXS_END_DECLS
+#endif
+
+#define _XOPEN_SOURCE 700
+#define OPENSSL_THREAD_DEFINES
+
+/**
+ * Define intended for use with strerror.
+ *
+ * char errbuf[MXS_STRERROR_BUFLEN];
+ * strerror_r(errno, errbuf, sizeof(errbuf))
+ */
+#define MXS_STRERROR_BUFLEN 512
+
+/**
+ * Returns the smaller of two items.
+ *
+ * @param a A value.
+ * @param b Another value.
+ *
+ * @return a if a is smaller than b, b otherwise.
+ *
+ * @note This a macro, so the arguments will be evaluated more than once.
+ */
+#define MXS_MIN(a,b) ((a)<(b) ? (a) : (b))
+
+/**
+ * Returns the larger of two items.
+ *
+ * @param a A value.
+ * @param b Another value.
+ *
+ * @return a if a is larger than b, b otherwise.
+ *
+ * @note This a macro, so the arguments will be evaluated more than once.
+ */
+#define MXS_MAX(a,b) ((a)>(b) ? (a) : (b))
+
+/**
+ * COMMON INCLUDE FILES
+ */
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
diff -urN MaxScale-maxscale-2.0.1.orig/server/modules/monitor/auroramon.c MaxScale-maxscale-2.0.1/server/modules/monitor/auroramon.c
--- MaxScale-maxscale-2.0.1.orig/server/modules/monitor/auroramon.c	1970-01-01 00:00:00.000000000 +0000
+++ MaxScale-maxscale-2.0.1/server/modules/monitor/auroramon.c	2016-11-08 17:14:53.380763231 +0000
@@ -0,0 +1,386 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+/**
+ * @file auroramon.c - Amazon RDS Aurora monitor
+ */
+
+#include <modinfo.h>
+#include <thread.h>
+#include <monitor.h>
+#include <mysqld_error.h>
+#include <alloc.h>
+#include <skygw_debug.h>
+
+static char *version_str = (char*)"V1.0.0";
+
+/*lint -e14 */
+MODULE_INFO info =
+{
+    MODULE_API_MONITOR,
+    MODULE_BETA_RELEASE,
+    MONITOR_VERSION,
+    "Aurora monitor"
+};
+/*lint +e14 */
+
+typedef struct aurora_monitor
+{
+    bool   shutdown;            /**< True if the monitor is stopped */
+    THREAD thread;              /**< Monitor thread */
+    char*  script;              /**< Launchable script */
+    bool   events[MAX_MONITOR_EVENT]; /**< Enabled monitor events */
+} AURORA_MONITOR;
+
+/**
+ * Implementation of the mandatory version entry point
+ *
+ * @return version string of the module
+ */
+/*lint -e14 */
+char *
+version()
+{
+    return version_str;
+}
+
+/**
+ * The module initialisation routine, called when the module is first loaded.
+ */
+/*lint -e14 */
+void
+ModuleInit()
+{
+}
+/*lint +e14 */
+
+/**
+ * @brief Update the status of a server
+ *
+ * This function connects to the database and queries it for its status. The
+ * status of the server is adjusted accordingly based on the results of the
+ * query.
+ *
+ * @param monitor  Monitor object
+ * @param database Server whose status should be updated
+ */
+void update_server_status(MONITOR *monitor, MONITOR_SERVERS *database)
+{
+    if (!SERVER_IN_MAINT(database->server))
+    {
+        SERVER temp_server = {.status = database->server->status};
+        server_clear_status(&temp_server, SERVER_RUNNING | SERVER_MASTER | SERVER_SLAVE | SERVER_AUTH_ERROR);
+        database->mon_prev_status = database->server->status;
+
+        /** Try to connect to or ping the database */
+        connect_result_t rval = mon_connect_to_db(monitor, database);
+
+        if (rval == MONITOR_CONN_OK)
+        {
+            server_set_status(&temp_server, SERVER_RUNNING);
+            MYSQL_RES *result;
+
+            /** Connection is OK, query for replica status */
+            if (mysql_query(database->con, "SELECT @@aurora_server_id, server_id FROM "
+                            "information_schema.replica_host_status "
+                            "WHERE session_id = 'MASTER_SESSION_ID'") == 0 &&
+                (result = mysql_store_result(database->con)))
+            {
+                ss_dassert(mysql_field_count(database->con) == 2);
+                MYSQL_ROW row = mysql_fetch_row(result);
+                int status = SERVER_SLAVE;
+
+                /** The master will return a row with two identical non-NULL fields */
+                if (row[0] && row[1] && strcmp(row[0], row[1]) == 0)
+                {
+                    status = SERVER_MASTER;
+                }
+
+                server_set_status(&temp_server, status);
+                mysql_free_result(result);
+            }
+            else
+            {
+                MXS_ERROR("Failed to query server %s (%s:%d): %d, %s",
+                          database->server->unique_name, database->server->name,
+                          database->server->port, mysql_errno(database->con),
+                          mysql_error(database->con));
+            }
+        }
+        else
+        {
+            /** Failed to connect to the database */
+            if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
+            {
+                server_set_status(&temp_server, SERVER_AUTH_ERROR);
+            }
+
+            if (mon_status_changed(database) && mon_print_fail_status(database))
+            {
+                mon_log_connect_error(database, rval);
+            }
+        }
+
+        server_transfer_status(database->server, &temp_server);
+    }
+}
+
+/**
+ * @brief Check if this is an event that the Aurora monitor handles
+ * @param event Event to check
+ * @return True if the event is monitored, false if it is not
+ * */
+bool is_aurora_event(monitor_event_t event)
+{
+    static monitor_event_t aurora_events[] =
+    {
+        MASTER_DOWN_EVENT,
+        MASTER_UP_EVENT,
+        SLAVE_DOWN_EVENT,
+        SLAVE_UP_EVENT,
+        SERVER_DOWN_EVENT,
+        SERVER_UP_EVENT,
+        LOST_MASTER_EVENT,
+        LOST_SLAVE_EVENT,
+        NEW_MASTER_EVENT,
+        NEW_SLAVE_EVENT,
+        MAX_MONITOR_EVENT
+    };
+
+    for (int i = 0; aurora_events[i] != MAX_MONITOR_EVENT; i++)
+    {
+        if (event == aurora_events[i])
+        {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+/**
+ * @brief Main monitoring loop
+ *
+ * @param arg The MONITOR object for this monitor
+ */
+static void
+monitorMain(void *arg)
+{
+    MONITOR *monitor = (MONITOR*)arg;
+    AURORA_MONITOR *handle = monitor->handle;
+
+    if (mysql_thread_init())
+    {
+        MXS_ERROR("mysql_thread_init failed in Aurora monitor. Exiting.");
+        return;
+    }
+
+    while (!handle->shutdown)
+    {
+        for (MONITOR_SERVERS *ptr = monitor->databases; ptr; ptr = ptr->next)
+        {
+            update_server_status(monitor, ptr);
+
+            if (SERVER_IS_DOWN(ptr->server))
+            {
+                /** Hang up all DCBs connected to the failed server */
+                dcb_hangup_foreach(ptr->server);
+            }
+        }
+
+        /**
+         * After updating the status of all servers, check if monitor events
+         * need to be launched.
+         *
+         * TODO: Move this functionality into monitor.c, it is duplicated in
+         * every monitor.
+         */
+        for (MONITOR_SERVERS *ptr = monitor->databases; ptr; ptr = ptr->next)
+        {
+            if (mon_status_changed(ptr))
+            {
+                monitor_event_t evtype = mon_get_event_type(ptr);
+                if (is_aurora_event(evtype))
+                {
+                    mon_log_state_change(ptr);
+                    if (handle->script && handle->events[evtype])
+                    {
+                        monitor_launch_script(monitor, ptr, handle->script);
+                    }
+                }
+            }
+        }
+
+        /** Sleep until the next monitoring interval */
+        int ms = 0;
+        while (ms < monitor->interval && !handle->shutdown)
+        {
+            thread_millisleep(MON_BASE_INTERVAL_MS);
+            ms += MON_BASE_INTERVAL_MS;
+        }
+    }
+
+    mysql_thread_end();
+}
+
+/**
+ * Helper function to free the monitor handle
+ */
+static void auroramon_free(AURORA_MONITOR *handle)
+{
+    if (handle)
+    {
+        MXS_FREE(handle->script);
+        MXS_FREE(handle);
+    }
+}
+
+/**
+ * @brief Start the monitor
+ *
+ * This function initializes the monitor and starts the monitoring thread.
+ *
+ * @param arg The MONITOR structure for this monitor
+ * @param opt The configuration parameters for this monitor
+ * @return Monitor handle
+ */
+static void *
+startMonitor(void *arg, void *opt)
+{
+    MONITOR* mon = (MONITOR*) arg;
+    CONFIG_PARAMETER* params = (CONFIG_PARAMETER*) opt;
+    bool have_events = false, script_error = false;
+    AURORA_MONITOR *handle = mon->handle;
+
+    if (handle)
+    {
+        handle->shutdown = false;
+    }
+    else
+    {
+        if ((handle = (AURORA_MONITOR *) MXS_MALLOC(sizeof(AURORA_MONITOR))) == NULL)
+        {
+            return NULL;
+        }
+
+        handle->shutdown = false;
+        handle->script = NULL;
+        memset(handle->events, false, sizeof(handle->events));
+
+        while (params)
+        {
+            if (strcmp(params->name, "script") == 0)
+            {
+                if (externcmd_can_execute(params->value))
+                {
+                    handle->script = MXS_STRDUP_A(params->value);
+                }
+                else
+                {
+                    script_error = true;
+                }
+            }
+            else if (strcmp(params->name, "events") == 0)
+            {
+                if (mon_parse_event_string(handle->events, sizeof(handle->events), params->value) != 0)
+                {
+                    script_error = true;
+                }
+                else
+                {
+                    have_events = true;
+                }
+            }
+            params = params->next;
+        }
+
+        if (!check_monitor_permissions(mon, "SELECT @@aurora_server_id, server_id FROM "
+                                       "information_schema.replica_host_status "
+                                       "WHERE session_id = 'MASTER_SESSION_ID'"))
+        {
+            MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
+            auroramon_free(handle);
+            return NULL;
+        }
+
+        if (script_error)
+        {
+            MXS_ERROR("Errors were found in the script configuration parameters "
+                      "for the monitor '%s'.", mon->name);
+            auroramon_free(handle);
+            return NULL;
+        }
+
+        /** If no specific events are given, enable them all */
+        if (!have_events)
+        {
+            memset(handle->events, true, sizeof(handle->events));
+        }
+    }
+
+    if (thread_start(&handle->thread, monitorMain, mon) == NULL)
+    {
+        MXS_ERROR("Failed to start monitor thread for monitor '%s'.", mon->name);
+        auroramon_free(handle);
+        return NULL;
+    }
+
+    return handle;
+}
+
+/**
+ * Stop a running monitor
+ *
+ * @param arg   Handle on thr running monior
+ */
+static void
+stopMonitor(void *arg)
+{
+    MONITOR* mon = (MONITOR*) arg;
+    AURORA_MONITOR *handle = (AURORA_MONITOR *) mon->handle;
+
+    handle->shutdown = true;
+    thread_wait(handle->thread);
+}
+
+/**
+ * Diagnostic interface
+ *
+ * @param dcb   DCB to send output
+ * @param mon   The monitor
+ */
+static void
+diagnostics(DCB *dcb, void *mon)
+{
+}
+
+static MONITOR_OBJECT MyObject =
+{
+    startMonitor,
+    stopMonitor,
+    diagnostics
+};
+
+/**
+ * The module entry point routine. It is this routine that must populate the
+ * structure that is referred to as the "module object", this is a structure
+ * with the set of external entry points for this module.
+ *
+ * @return The module object
+ */
+MONITOR_OBJECT *
+GetModuleObject()
+{
+    return &MyObject;
+}
+/*lint +e14 */
diff -urN MaxScale-maxscale-2.0.1.orig/server/modules/monitor/CMakeLists.txt MaxScale-maxscale-2.0.1/server/modules/monitor/CMakeLists.txt
--- MaxScale-maxscale-2.0.1.orig/server/modules/monitor/CMakeLists.txt	2016-09-29 20:48:21.000000000 +0000
+++ MaxScale-maxscale-2.0.1/server/modules/monitor/CMakeLists.txt	2016-11-08 11:39:51.276315719 +0000
@@ -16,6 +16,12 @@
 set_target_properties(ndbclustermon PROPERTIES VERSION "2.1.0")
 install(TARGETS ndbclustermon DESTINATION ${MAXSCALE_LIBDIR})
 
+add_library(auroramon SHARED auroramon.c)
+target_link_libraries(auroramon maxscale-common)
+add_dependencies(auroramon pcre2)
+set_target_properties(auroramon PROPERTIES VERSION "1.0.0")
+install(TARGETS auroramon DESTINATION ${MAXSCALE_LIBDIR})
+
 if(BUILD_MMMON)
   add_library(mmmon SHARED mmmon.c)
   target_link_libraries(mmmon maxscale-common)