xref: /netbsd/external/mit/libuv/dist/src/timer.c (revision b29f2fbf)
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7  * furnished to do so, subject to the following conditions:
8  *
9  * The above copyright notice and this permission notice shall be included in
10  * all copies or substantial portions of the Software.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
15  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
16  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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18  * IN THE SOFTWARE.
19  */
20 
21 #include "uv.h"
22 #include "uv-common.h"
23 #include "heap-inl.h"
24 
25 #include <assert.h>
26 #include <limits.h>
27 
28 
timer_heap(const uv_loop_t * loop)29 static struct heap *timer_heap(const uv_loop_t* loop) {
30 #ifdef _WIN32
31   return (struct heap*) loop->timer_heap;
32 #else
33   return (struct heap*) &loop->timer_heap;
34 #endif
35 }
36 
37 
timer_less_than(const struct heap_node * ha,const struct heap_node * hb)38 static int timer_less_than(const struct heap_node* ha,
39                            const struct heap_node* hb) {
40   const uv_timer_t* a;
41   const uv_timer_t* b;
42 
43   a = container_of(ha, uv_timer_t, heap_node);
44   b = container_of(hb, uv_timer_t, heap_node);
45 
46   if (a->timeout < b->timeout)
47     return 1;
48   if (b->timeout < a->timeout)
49     return 0;
50 
51   /* Compare start_id when both have the same timeout. start_id is
52    * allocated with loop->timer_counter in uv_timer_start().
53    */
54   return a->start_id < b->start_id;
55 }
56 
57 
uv_timer_init(uv_loop_t * loop,uv_timer_t * handle)58 int uv_timer_init(uv_loop_t* loop, uv_timer_t* handle) {
59   uv__handle_init(loop, (uv_handle_t*)handle, UV_TIMER);
60   handle->timer_cb = NULL;
61   handle->timeout = 0;
62   handle->repeat = 0;
63   return 0;
64 }
65 
66 
uv_timer_start(uv_timer_t * handle,uv_timer_cb cb,uint64_t timeout,uint64_t repeat)67 int uv_timer_start(uv_timer_t* handle,
68                    uv_timer_cb cb,
69                    uint64_t timeout,
70                    uint64_t repeat) {
71   uint64_t clamped_timeout;
72 
73   if (uv__is_closing(handle) || cb == NULL)
74     return UV_EINVAL;
75 
76   if (uv__is_active(handle))
77     uv_timer_stop(handle);
78 
79   clamped_timeout = handle->loop->time + timeout;
80   if (clamped_timeout < timeout)
81     clamped_timeout = (uint64_t) -1;
82 
83   handle->timer_cb = cb;
84   handle->timeout = clamped_timeout;
85   handle->repeat = repeat;
86   /* start_id is the second index to be compared in timer_less_than() */
87   handle->start_id = handle->loop->timer_counter++;
88 
89   heap_insert(timer_heap(handle->loop),
90               (struct heap_node*) &handle->heap_node,
91               timer_less_than);
92   uv__handle_start(handle);
93 
94   return 0;
95 }
96 
97 
uv_timer_stop(uv_timer_t * handle)98 int uv_timer_stop(uv_timer_t* handle) {
99   if (!uv__is_active(handle))
100     return 0;
101 
102   heap_remove(timer_heap(handle->loop),
103               (struct heap_node*) &handle->heap_node,
104               timer_less_than);
105   uv__handle_stop(handle);
106 
107   return 0;
108 }
109 
110 
uv_timer_again(uv_timer_t * handle)111 int uv_timer_again(uv_timer_t* handle) {
112   if (handle->timer_cb == NULL)
113     return UV_EINVAL;
114 
115   if (handle->repeat) {
116     uv_timer_stop(handle);
117     uv_timer_start(handle, handle->timer_cb, handle->repeat, handle->repeat);
118   }
119 
120   return 0;
121 }
122 
123 
uv_timer_set_repeat(uv_timer_t * handle,uint64_t repeat)124 void uv_timer_set_repeat(uv_timer_t* handle, uint64_t repeat) {
125   handle->repeat = repeat;
126 }
127 
128 
uv_timer_get_repeat(const uv_timer_t * handle)129 uint64_t uv_timer_get_repeat(const uv_timer_t* handle) {
130   return handle->repeat;
131 }
132 
133 
uv_timer_get_due_in(const uv_timer_t * handle)134 uint64_t uv_timer_get_due_in(const uv_timer_t* handle) {
135   if (handle->loop->time >= handle->timeout)
136     return 0;
137 
138   return handle->timeout - handle->loop->time;
139 }
140 
141 
uv__next_timeout(const uv_loop_t * loop)142 int uv__next_timeout(const uv_loop_t* loop) {
143   const struct heap_node* heap_node;
144   const uv_timer_t* handle;
145   uint64_t diff;
146 
147   heap_node = heap_min(timer_heap(loop));
148   if (heap_node == NULL)
149     return -1; /* block indefinitely */
150 
151   handle = container_of(heap_node, uv_timer_t, heap_node);
152   if (handle->timeout <= loop->time)
153     return 0;
154 
155   diff = handle->timeout - loop->time;
156   if (diff > INT_MAX)
157     diff = INT_MAX;
158 
159   return (int) diff;
160 }
161 
162 
uv__run_timers(uv_loop_t * loop)163 void uv__run_timers(uv_loop_t* loop) {
164   struct heap_node* heap_node;
165   uv_timer_t* handle;
166 
167   for (;;) {
168     heap_node = heap_min(timer_heap(loop));
169     if (heap_node == NULL)
170       break;
171 
172     handle = container_of(heap_node, uv_timer_t, heap_node);
173     if (handle->timeout > loop->time)
174       break;
175 
176     uv_timer_stop(handle);
177     uv_timer_again(handle);
178     handle->timer_cb(handle);
179   }
180 }
181 
182 
uv__timer_close(uv_timer_t * handle)183 void uv__timer_close(uv_timer_t* handle) {
184   uv_timer_stop(handle);
185 }
186