summaryrefslogtreecommitdiff
path: root/lib/tevent/tevent_queue.c
blob: 6c8fbe4f95f0acf6042f72cdd04b29b1f9ea71de (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/*
   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"

struct tevent_queue_entry {
	struct tevent_queue_entry *prev, *next;
	struct tevent_queue *queue;

	bool triggered;

	struct tevent_req *req;

	tevent_queue_trigger_fn_t trigger;
	void *private_data;
};

struct tevent_queue {
	const char *name;
	const char *location;

	bool running;
	struct tevent_timer *timer;

	size_t length;
	struct tevent_queue_entry *list;
};

static int tevent_queue_entry_destructor(struct tevent_queue_entry *e)
{
	struct tevent_queue *q = e->queue;

	if (!q) {
		return 0;
	}

	DLIST_REMOVE(q->list, e);
	q->length--;

	if (e->triggered &&
	    q->running &&
	    q->list) {
		q->list->triggered = true;
		q->list->trigger(q->list->req,
				 q->list->private_data);
	}

	return 0;
}

static int tevent_queue_destructor(struct tevent_queue *q)
{
	q->running = false;

	while (q->list) {
		struct tevent_queue_entry *e = q->list;
		talloc_free(e);
	}

	return 0;
}

struct tevent_queue *_tevent_queue_create(TALLOC_CTX *mem_ctx,
					  const char *name,
					  const char *location)
{
	struct tevent_queue *queue;

	queue = talloc_zero(mem_ctx, struct tevent_queue);
	if (!queue) {
		return NULL;
	}

	queue->name = talloc_strdup(queue, name);
	if (!queue->name) {
		talloc_free(queue);
		return NULL;
	}

	queue->location = location;

	/* queue is running by default */
	queue->running = true;

	talloc_set_destructor(queue, tevent_queue_destructor);
	return queue;
}

static void tevent_queue_timer_start(struct tevent_context *ev,
				     struct tevent_timer *te,
				     struct timeval now,
				     void *private_data)
{
	struct tevent_queue *q = talloc_get_type(private_data,
				  struct tevent_queue);

	talloc_free(te);
	q->timer = NULL;

	q->list->triggered = true;
	q->list->trigger(q->list->req, q->list->private_data);
}

bool tevent_queue_add(struct tevent_queue *queue,
		      struct tevent_context *ev,
		      struct tevent_req *req,
		      tevent_queue_trigger_fn_t trigger,
		      void *private_data)
{
	struct tevent_queue_entry *e;

	e = talloc_zero(req, struct tevent_queue_entry);
	if (e == NULL) {
		return false;
	}

	e->queue = queue;
	e->req = req;
	e->trigger = trigger;
	e->private_data = private_data;

	if (queue->running &&
	    !queue->timer &&
	    !queue->list) {
		queue->timer = tevent_add_timer(ev, queue, tevent_timeval_zero(),
						tevent_queue_timer_start,
						queue);
		if (!queue->timer) {
			talloc_free(e);
			return false;
		}
	}

	DLIST_ADD_END(queue->list, e, struct tevent_queue_entry *);
	queue->length++;
	talloc_set_destructor(e, tevent_queue_entry_destructor);

	return true;
}

bool tevent_queue_start(struct tevent_queue *queue,
			struct tevent_context *ev)
{
	if (queue->running) {
		/* already started */
		return true;
	}

	if (!queue->timer &&
	    queue->list) {
		queue->timer = tevent_add_timer(ev, queue, tevent_timeval_zero(),
						tevent_queue_timer_start,
						queue);
		if (!queue->timer) {
			return false;
		}
	}

	queue->running = true;

	return true;
}

void tevent_queue_stop(struct tevent_queue *queue)
{
	queue->running = false;
	talloc_free(queue->timer);
	queue->timer = NULL;
}

size_t tevent_queue_length(struct tevent_queue *queue)
{
	return queue->length;
}