mirror of
https://github.com/samba-team/samba.git
synced 2024-12-25 23:21:54 +03:00
c6f39b46a7
This is necessary for requests that have multiple results. Examples would be SMBEcho and ldap_search.
363 lines
9.1 KiB
C
363 lines
9.1 KiB
C
/*
|
|
Unix SMB/CIFS implementation.
|
|
Infrastructure for async requests
|
|
Copyright (C) Volker Lendecke 2008
|
|
Copyright (C) Stefan Metzmacher 2009
|
|
|
|
** NOTE! The following LGPL license applies to the tevent
|
|
** library. This does NOT imply that all of Samba is released
|
|
** under the LGPL
|
|
|
|
This 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 3 of the License, or (at your option) any later version.
|
|
|
|
This 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 this library; if not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "replace.h"
|
|
#include "tevent.h"
|
|
#include "tevent_internal.h"
|
|
#include "tevent_util.h"
|
|
|
|
/**
|
|
* @brief The default print function for creating debug messages
|
|
* @param[in] req The request to be printed
|
|
* @param[in] mem_ctx The memory context for the result
|
|
* @retval Text representation of req
|
|
*
|
|
* The function should not be used by users of the asynx API,
|
|
* but custom print function can use it and append custom text
|
|
* to the string.
|
|
*/
|
|
|
|
char *tevent_req_default_print(struct tevent_req *req, TALLOC_CTX *mem_ctx)
|
|
{
|
|
return talloc_asprintf(mem_ctx,
|
|
"tevent_req[%p/%s]: state[%d] error[%lld (0x%llX)] "
|
|
" state[%s (%p)] timer[%p]",
|
|
req, req->internal.create_location,
|
|
req->internal.state,
|
|
(unsigned long long)req->internal.error,
|
|
(unsigned long long)req->internal.error,
|
|
talloc_get_name(req->data),
|
|
req->data,
|
|
req->internal.timer
|
|
);
|
|
}
|
|
|
|
/**
|
|
* @brief Print an tevent_req structure in debug messages
|
|
* @param[in] mem_ctx The memory context for the result
|
|
* @param[in] req The request to be printed
|
|
* @retval Text representation of req
|
|
*
|
|
* This function should be used by callers of the async API
|
|
*/
|
|
|
|
char *tevent_req_print(TALLOC_CTX *mem_ctx, struct tevent_req *req)
|
|
{
|
|
if (!req->private_print) {
|
|
return tevent_req_default_print(req, mem_ctx);
|
|
}
|
|
|
|
return req->private_print(req, mem_ctx);
|
|
}
|
|
|
|
/**
|
|
* @brief Create an async request
|
|
* @param[in] mem_ctx The memory context for the result
|
|
* @param[in] ev The event context this async request will be driven by
|
|
* @retval A new async request
|
|
*
|
|
* The new async request will be initialized in state ASYNC_REQ_IN_PROGRESS
|
|
*/
|
|
|
|
struct tevent_req *_tevent_req_create(TALLOC_CTX *mem_ctx,
|
|
void *pdata,
|
|
size_t data_size,
|
|
const char *type,
|
|
const char *location)
|
|
{
|
|
struct tevent_req *req;
|
|
void **ppdata = (void **)pdata;
|
|
void *data;
|
|
|
|
req = talloc_zero(mem_ctx, struct tevent_req);
|
|
if (req == NULL) {
|
|
return NULL;
|
|
}
|
|
req->internal.private_type = type;
|
|
req->internal.create_location = location;
|
|
req->internal.finish_location = NULL;
|
|
req->internal.state = TEVENT_REQ_IN_PROGRESS;
|
|
req->internal.trigger = tevent_create_immediate(req);
|
|
if (!req->internal.trigger) {
|
|
talloc_free(req);
|
|
return NULL;
|
|
}
|
|
|
|
data = talloc_size(req, data_size);
|
|
if (data == NULL) {
|
|
talloc_free(req);
|
|
return NULL;
|
|
}
|
|
talloc_set_name_const(data, type);
|
|
|
|
req->data = data;
|
|
|
|
*ppdata = data;
|
|
return req;
|
|
}
|
|
|
|
void _tevent_req_notify_callback(struct tevent_req *req, const char *location)
|
|
{
|
|
req->internal.finish_location = location;
|
|
if (req->async.fn != NULL) {
|
|
req->async.fn(req);
|
|
}
|
|
}
|
|
|
|
static void tevent_req_finish(struct tevent_req *req,
|
|
enum tevent_req_state state,
|
|
const char *location)
|
|
{
|
|
req->internal.state = state;
|
|
_tevent_req_notify_callback(req, location);
|
|
}
|
|
|
|
/**
|
|
* @brief An async request has successfully finished
|
|
* @param[in] req The finished request
|
|
*
|
|
* tevent_req_done is to be used by implementors of async requests. When a
|
|
* request is successfully finished, this function calls the user's completion
|
|
* function.
|
|
*/
|
|
|
|
void _tevent_req_done(struct tevent_req *req,
|
|
const char *location)
|
|
{
|
|
tevent_req_finish(req, TEVENT_REQ_DONE, location);
|
|
}
|
|
|
|
/**
|
|
* @brief An async request has seen an error
|
|
* @param[in] req The request with an error
|
|
* @param[in] error The error code
|
|
*
|
|
* tevent_req_done is to be used by implementors of async requests. When a
|
|
* request can not successfully completed, the implementation should call this
|
|
* function with the appropriate status code.
|
|
*
|
|
* If error is 0 the function returns false and does nothing more.
|
|
*
|
|
* Call pattern would be
|
|
* \code
|
|
* int error = first_function();
|
|
* if (tevent_req_error(req, error)) {
|
|
* return;
|
|
* }
|
|
*
|
|
* error = second_function();
|
|
* if (tevent_req_error(req, error)) {
|
|
* return;
|
|
* }
|
|
*
|
|
* tevent_req_done(req);
|
|
* return;
|
|
* \endcode
|
|
*/
|
|
|
|
bool _tevent_req_error(struct tevent_req *req,
|
|
uint64_t error,
|
|
const char *location)
|
|
{
|
|
if (error == 0) {
|
|
return false;
|
|
}
|
|
|
|
req->internal.error = error;
|
|
tevent_req_finish(req, TEVENT_REQ_USER_ERROR, location);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* @brief Helper function for nomem check
|
|
* @param[in] p The pointer to be checked
|
|
* @param[in] req The request being processed
|
|
*
|
|
* Convenience helper to easily check alloc failure within a callback
|
|
* implementing the next step of an async request.
|
|
*
|
|
* Call pattern would be
|
|
* \code
|
|
* p = talloc(mem_ctx, bla);
|
|
* if (tevent_req_nomem(p, req)) {
|
|
* return;
|
|
* }
|
|
* \endcode
|
|
*/
|
|
|
|
bool _tevent_req_nomem(const void *p,
|
|
struct tevent_req *req,
|
|
const char *location)
|
|
{
|
|
if (p != NULL) {
|
|
return false;
|
|
}
|
|
tevent_req_finish(req, TEVENT_REQ_NO_MEMORY, location);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* @brief Immediate event callback
|
|
* @param[in] ev Event context
|
|
* @param[in] im The immediate event
|
|
* @param[in] priv The async request to be finished
|
|
*/
|
|
static void tevent_req_trigger(struct tevent_context *ev,
|
|
struct tevent_immediate *im,
|
|
void *private_data)
|
|
{
|
|
struct tevent_req *req = talloc_get_type(private_data,
|
|
struct tevent_req);
|
|
|
|
tevent_req_finish(req, req->internal.state,
|
|
req->internal.finish_location);
|
|
}
|
|
|
|
/**
|
|
* @brief Finish a request before the caller had the change to set the callback
|
|
* @param[in] req The finished request
|
|
* @param[in] ev The tevent_context for the timed event
|
|
* @retval req will be returned
|
|
*
|
|
* An implementation of an async request might find that it can either finish
|
|
* the request without waiting for an external event, or it can't even start
|
|
* the engine. To present the illusion of a callback to the user of the API,
|
|
* the implementation can call this helper function which triggers an
|
|
* immediate timed event. This way the caller can use the same calling
|
|
* conventions, independent of whether the request was actually deferred.
|
|
*/
|
|
|
|
struct tevent_req *tevent_req_post(struct tevent_req *req,
|
|
struct tevent_context *ev)
|
|
{
|
|
tevent_schedule_immediate(req->internal.trigger,
|
|
ev, tevent_req_trigger, req);
|
|
return req;
|
|
}
|
|
|
|
bool tevent_req_is_in_progress(struct tevent_req *req)
|
|
{
|
|
if (req->internal.state == TEVENT_REQ_IN_PROGRESS) {
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* @brief This function destroys the attached private data
|
|
* @param[in] req The finished request
|
|
*
|
|
* This function can be called as last action of a _recv()
|
|
* function, it destroys the data attached to the tevent_req.
|
|
*/
|
|
void tevent_req_received(struct tevent_req *req)
|
|
{
|
|
TALLOC_FREE(req->data);
|
|
req->private_print = NULL;
|
|
|
|
TALLOC_FREE(req->internal.trigger);
|
|
TALLOC_FREE(req->internal.timer);
|
|
|
|
req->internal.state = TEVENT_REQ_RECEIVED;
|
|
}
|
|
|
|
bool tevent_req_poll(struct tevent_req *req,
|
|
struct tevent_context *ev)
|
|
{
|
|
while (tevent_req_is_in_progress(req)) {
|
|
int ret;
|
|
|
|
ret = tevent_loop_once(ev);
|
|
if (ret != 0) {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool tevent_req_is_error(struct tevent_req *req, enum tevent_req_state *state,
|
|
uint64_t *error)
|
|
{
|
|
if (req->internal.state == TEVENT_REQ_DONE) {
|
|
return false;
|
|
}
|
|
if (req->internal.state == TEVENT_REQ_USER_ERROR) {
|
|
*error = req->internal.error;
|
|
}
|
|
*state = req->internal.state;
|
|
return true;
|
|
}
|
|
|
|
static void tevent_req_timedout(struct tevent_context *ev,
|
|
struct tevent_timer *te,
|
|
struct timeval now,
|
|
void *private_data)
|
|
{
|
|
struct tevent_req *req = talloc_get_type(private_data,
|
|
struct tevent_req);
|
|
|
|
TALLOC_FREE(req->internal.timer);
|
|
|
|
tevent_req_finish(req, TEVENT_REQ_TIMED_OUT, __FUNCTION__);
|
|
}
|
|
|
|
bool tevent_req_set_endtime(struct tevent_req *req,
|
|
struct tevent_context *ev,
|
|
struct timeval endtime)
|
|
{
|
|
TALLOC_FREE(req->internal.timer);
|
|
|
|
req->internal.timer = tevent_add_timer(ev, req, endtime,
|
|
tevent_req_timedout,
|
|
req);
|
|
if (tevent_req_nomem(req->internal.timer, req)) {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void tevent_req_set_callback(struct tevent_req *req, tevent_req_fn fn, void *pvt)
|
|
{
|
|
req->async.fn = fn;
|
|
req->async.private_data = pvt;
|
|
}
|
|
|
|
void *_tevent_req_callback_data(struct tevent_req *req)
|
|
{
|
|
return req->async.private_data;
|
|
}
|
|
|
|
void *_tevent_req_data(struct tevent_req *req)
|
|
{
|
|
return req->data;
|
|
}
|
|
|
|
void tevent_req_set_print_fn(struct tevent_req *req, tevent_req_print_fn fn)
|
|
{
|
|
req->private_print = fn;
|
|
}
|