1 /*
2 This file is part of Deadbeef Player source code
3 http://deadbeef.sourceforge.net
4
5 generic message queue implementation
6
7 Copyright (C) 2009-2013 Alexey Yakovenko
8
9 This software is provided 'as-is', without any express or implied
10 warranty. In no event will the authors be held liable for any damages
11 arising from the use of this software.
12
13 Permission is granted to anyone to use this software for any purpose,
14 including commercial applications, and to alter it and redistribute it
15 freely, subject to the following restrictions:
16
17 1. The origin of this software must not be misrepresented; you must not
18 claim that you wrote the original software. If you use this software
19 in a product, an acknowledgment in the product documentation would be
20 appreciated but is not required.
21 2. Altered source versions must be plainly marked as such, and must not be
22 misrepresented as being the original software.
23 3. This notice may not be removed or altered from any source distribution.
24
25 Alexey Yakovenko waker@users.sourceforge.net
26 */
27 #include "handler.h"
28 #include <stdio.h>
29 #include <string.h>
30 #include <assert.h>
31 #include <stdlib.h>
32 #include "handler.h"
33 #include "threading.h"
34
35 typedef struct message_s {
36 uint32_t id;
37 uintptr_t ctx;
38 uint32_t p1;
39 uint32_t p2;
40 struct message_s *next;
41 } message_t;
42
43 typedef struct handler_s {
44 int queue_size;
45 message_t *mfree;
46 message_t *mqueue;
47 message_t *mqtail;
48 uintptr_t mutex;
49 uintptr_t cond;
50 message_t pool[1];
51 } handler_t;
52
53 void
handler_reset(handler_t * h)54 handler_reset (handler_t *h) {
55 h->mqueue = NULL;
56 h->mfree = NULL;
57 h->mqtail = NULL;
58 memset (h->pool, 0, sizeof (message_t) * h->queue_size);
59 for (int i = 0; i < h->queue_size; i++) {
60 h->pool[i].next = h->mfree;
61 h->mfree = &h->pool[i];
62 }
63 }
64
65 handler_t *
handler_alloc(int queue_size)66 handler_alloc (int queue_size) {
67 int sz = sizeof (handler_t) + (queue_size-1) * sizeof (message_t);
68 handler_t *h = malloc (sz);
69 memset (h, 0, sz);
70 h->queue_size = queue_size;
71 h->mutex = mutex_create ();
72 h->cond = cond_create ();
73 handler_reset (h);
74 return h;
75 }
76
77 void
handler_free(handler_t * h)78 handler_free (handler_t *h) {
79 mutex_lock (h->mutex);
80 handler_reset (h);
81 mutex_unlock (h->mutex);
82 mutex_free (h->mutex);
83 cond_free (h->cond);
84 free (h);
85 }
86
87 int
handler_push(handler_t * h,uint32_t id,uintptr_t ctx,uint32_t p1,uint32_t p2)88 handler_push (handler_t *h, uint32_t id, uintptr_t ctx, uint32_t p1, uint32_t p2) {
89 if (!h) {
90 return -1;
91 }
92 if (!h->mfree) {
93 return -1;
94 }
95 mutex_lock (h->mutex);
96 message_t *msg = h->mfree;
97 h->mfree = h->mfree->next;
98 if (h->mqtail) {
99 h->mqtail->next = msg;
100 }
101 h->mqtail = msg;
102 if (!h->mqueue) {
103 h->mqueue = msg;
104 }
105
106 msg->next = NULL;
107 msg->id = id;
108 msg->ctx = ctx;
109 msg->p1 = p1;
110 msg->p2 = p2;
111 mutex_unlock (h->mutex);
112 cond_signal (h->cond);
113 return 0;
114 }
115
116 void
handler_wait(handler_t * h)117 handler_wait (handler_t *h) {
118 cond_wait (h->cond, h->mutex);
119 mutex_unlock (h->mutex);
120 }
121
122 int
handler_pop(handler_t * h,uint32_t * id,uintptr_t * ctx,uint32_t * p1,uint32_t * p2)123 handler_pop (handler_t *h, uint32_t *id, uintptr_t *ctx, uint32_t *p1, uint32_t *p2) {
124 mutex_lock (h->mutex);
125 if (!h->mqueue) {
126 mutex_unlock (h->mutex);
127 return -1;
128 }
129 *id = h->mqueue->id;
130 *ctx = h->mqueue->ctx;
131 *p1 = h->mqueue->p1;
132 *p2 = h->mqueue->p2;
133 message_t *next = h->mqueue->next;
134 h->mqueue->next = h->mfree;
135 h->mfree = h->mqueue;
136 h->mqueue = next;
137 if (!h->mqueue) {
138 h->mqtail = NULL;
139 }
140 mutex_unlock (h->mutex);
141 return 0;
142 }
143
144 int
handler_hasmessages(handler_t * h)145 handler_hasmessages (handler_t *h) {
146 return h->mqueue ? 1 : 0;
147 }
148
149