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27 
28 #ifndef CND_MONOTONIC_H
29 #define CND_MONOTONIC_H
30 
31 #include "c11/threads.h"
32 #include "util/os_time.h"
33 
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37 
38 struct u_cnd_monotonic
39 {
40 #ifdef _WIN32
41    CONDITION_VARIABLE condvar;
42 #else
43    pthread_cond_t cond;
44 #endif
45 };
46 
47 static inline int
u_cnd_monotonic_init(struct u_cnd_monotonic * cond)48 u_cnd_monotonic_init(struct u_cnd_monotonic *cond)
49 {
50    assert(cond != NULL);
51 
52 #ifdef _WIN32
53    InitializeConditionVariable(&cond->condvar);
54    return thrd_success;
55 #else
56    int ret = thrd_error;
57    pthread_condattr_t condattr;
58    if (pthread_condattr_init(&condattr) == 0) {
59       if ((pthread_condattr_setclock(&condattr, CLOCK_MONOTONIC) == 0) &&
60          (pthread_cond_init(&cond->cond, &condattr) == 0)) {
61          ret = thrd_success;
62       }
63 
64       pthread_condattr_destroy(&condattr);
65    }
66 
67    return ret;
68 #endif
69 }
70 
71 static inline void
u_cnd_monotonic_destroy(struct u_cnd_monotonic * cond)72 u_cnd_monotonic_destroy(struct u_cnd_monotonic *cond)
73 {
74    assert(cond != NULL);
75 
76 #ifdef _WIN32
77    // Do nothing
78 #else
79    pthread_cond_destroy(&cond->cond);
80 #endif
81 }
82 
83 static inline int
u_cnd_monotonic_broadcast(struct u_cnd_monotonic * cond)84 u_cnd_monotonic_broadcast(struct u_cnd_monotonic *cond)
85 {
86    assert(cond != NULL);
87 
88 #ifdef _WIN32
89    WakeAllConditionVariable(&cond->condvar);
90    return thrd_success;
91 #else
92    return (pthread_cond_broadcast(&cond->cond) == 0) ? thrd_success : thrd_error;
93 #endif
94 }
95 
96 static inline int
u_cnd_monotonic_signal(struct u_cnd_monotonic * cond)97 u_cnd_monotonic_signal(struct u_cnd_monotonic *cond)
98 {
99    assert(cond != NULL);
100 
101 #ifdef _WIN32
102    WakeConditionVariable(&cond->condvar);
103    return thrd_success;
104 #else
105    return (pthread_cond_signal(&cond->cond) == 0) ? thrd_success : thrd_error;
106 #endif
107 }
108 
109 static inline int
u_cnd_monotonic_timedwait(struct u_cnd_monotonic * cond,mtx_t * mtx,const struct timespec * abs_time)110 u_cnd_monotonic_timedwait(struct u_cnd_monotonic *cond, mtx_t *mtx, const struct timespec *abs_time)
111 {
112    assert(cond != NULL);
113    assert(mtx != NULL);
114    assert(abs_time != NULL);
115 
116 #ifdef _WIN32
117    const uint64_t future = (abs_time->tv_sec * 1000) + (abs_time->tv_nsec / 1000000);
118    const uint64_t now = os_time_get_nano() / 1000000;
119    const DWORD timeout = (future > now) ? (DWORD)(future - now) : 0;
120    if (SleepConditionVariableCS(&cond->condvar, mtx, timeout))
121       return thrd_success;
122    return (GetLastError() == ERROR_TIMEOUT) ? thrd_busy : thrd_error;
123 #else
124    int rt = pthread_cond_timedwait(&cond->cond, mtx, abs_time);
125    if (rt == ETIMEDOUT)
126       return thrd_busy;
127    return (rt == 0) ? thrd_success : thrd_error;
128 #endif
129 }
130 
131 static inline int
u_cnd_monotonic_wait(struct u_cnd_monotonic * cond,mtx_t * mtx)132 u_cnd_monotonic_wait(struct u_cnd_monotonic *cond, mtx_t *mtx)
133 {
134    assert(cond != NULL);
135    assert(mtx != NULL);
136 
137 #ifdef _WIN32
138    SleepConditionVariableCS(&cond->condvar, mtx, INFINITE);
139    return thrd_success;
140 #else
141    return (pthread_cond_wait(&cond->cond, mtx) == 0) ? thrd_success : thrd_error;
142 #endif
143 }
144 
145 #ifdef __cplusplus
146 }
147 #endif
148 
149 #endif
150