Files
mongo/examples/c/ex_event_handler.c
2016-03-18 19:27:53 -04:00

137 lines
4.0 KiB
C

/*-
* Public Domain 2014-2016 MongoDB, Inc.
* Public Domain 2008-2014 WiredTiger, Inc.
*
* This is free and unencumbered software released into the public domain.
*
* Anyone is free to copy, modify, publish, use, compile, sell, or
* distribute this software, either in source code form or as a compiled
* binary, for any purpose, commercial or non-commercial, and by any
* means.
*
* In jurisdictions that recognize copyright laws, the author or authors
* of this software dedicate any and all copyright interest in the
* software to the public domain. We make this dedication for the benefit
* of the public at large and to the detriment of our heirs and
* successors. We intend this dedication to be an overt act of
* relinquishment in perpetuity of all present and future rights to this
* software under copyright law.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* ex_event_handler.c
* Demonstrate how to use the WiredTiger event handler mechanism.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wiredtiger.h>
static const char *home;
int handle_wiredtiger_error(
WT_EVENT_HANDLER *, WT_SESSION *, int, const char *);
int handle_wiredtiger_message(WT_EVENT_HANDLER *, WT_SESSION *, const char *);
/*! [Function event_handler] */
/*
* Create our own event handler structure to allow us to pass context through
* to event handler callbacks. For this to work the WiredTiger event handler
* must appear first in our custom event handler structure.
*/
typedef struct {
WT_EVENT_HANDLER h;
const char *app_id;
} CUSTOM_EVENT_HANDLER;
/*
* handle_wiredtiger_error --
* Function to handle error callbacks from WiredTiger.
*/
int
handle_wiredtiger_error(WT_EVENT_HANDLER *handler,
WT_SESSION *session, int error, const char *message)
{
CUSTOM_EVENT_HANDLER *custom_handler;
/* Cast the handler back to our custom handler. */
custom_handler = (CUSTOM_EVENT_HANDLER *)handler;
/* Report the error on the console. */
fprintf(stderr,
"app_id %s, thread context %p, error %d, message %s\n",
custom_handler->app_id, session, error, message);
return (0);
}
/*
* handle_wiredtiger_message --
* Function to handle message callbacks from WiredTiger.
*/
int
handle_wiredtiger_message(
WT_EVENT_HANDLER *handler, WT_SESSION *session, const char *message)
{
/* Cast the handler back to our custom handler. */
printf("app id %s, thread context %p, message %s\n",
((CUSTOM_EVENT_HANDLER *)handler)->app_id, session, message);
return (0);
}
/*! [Function event_handler] */
static int
config_event_handler(void)
{
WT_CONNECTION *conn;
WT_SESSION *session;
int ret;
/*! [Configure event_handler] */
CUSTOM_EVENT_HANDLER event_handler;
event_handler.h.handle_error = handle_wiredtiger_error;
event_handler.h.handle_message = handle_wiredtiger_message;
/* Set handlers to NULL to use the default handler. */
event_handler.h.handle_progress = NULL;
event_handler.h.handle_close = NULL;
event_handler.app_id = "example_event_handler";
ret = wiredtiger_open(home,
(WT_EVENT_HANDLER *)&event_handler, "create", &conn);
/*! [Configure event_handler] */
/* Make an invalid API call, to ensure the event handler works. */
(void)conn->open_session(conn, NULL, "isolation=invalid", &session);
if (ret == 0)
ret = conn->close(conn, NULL);
return (ret);
}
int
main(void)
{
/*
* Create a clean test directory for this run of the test program if the
* environment variable isn't already set (as is done by make check).
*/
if (getenv("WIREDTIGER_HOME") == NULL) {
home = "WT_HOME";
(void)system("rm -rf WT_HOME && mkdir WT_HOME");
} else
home = NULL;
return (config_event_handler());
}