1 /* 2 * GLIB Compatibility Functions 3 * 4 * Copyright IBM, Corp. 2013 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * Michael Tokarev <mjt@tls.msk.ru> 9 * Paolo Bonzini <pbonzini@redhat.com> 10 * 11 * This work is licensed under the terms of the GNU GPL, version 2 or later. 12 * See the COPYING file in the top-level directory. 13 * 14 */ 15 16 #ifndef QEMU_GLIB_COMPAT_H 17 #define QEMU_GLIB_COMPAT_H 18 19 #include <glib.h> 20 21 /* GLIB version compatibility flags */ 22 #if !GLIB_CHECK_VERSION(2, 26, 0) 23 #define G_TIME_SPAN_SECOND (G_GINT64_CONSTANT(1000000)) 24 #endif 25 26 #if !GLIB_CHECK_VERSION(2, 28, 0) 27 static inline gint64 qemu_g_get_monotonic_time(void) 28 { 29 /* g_get_monotonic_time() is best-effort so we can use the wall clock as a 30 * fallback. 31 */ 32 33 GTimeVal time; 34 g_get_current_time(&time); 35 36 return time.tv_sec * G_TIME_SPAN_SECOND + time.tv_usec; 37 } 38 /* work around distro backports of this interface */ 39 #define g_get_monotonic_time() qemu_g_get_monotonic_time() 40 #endif 41 42 #ifdef _WIN32 43 /* 44 * g_poll has a problem on Windows when using 45 * timeouts < 10ms, so use wrapper. 46 */ 47 #define g_poll(fds, nfds, timeout) g_poll_fixed(fds, nfds, timeout) 48 gint g_poll_fixed(GPollFD *fds, guint nfds, gint timeout); 49 #endif 50 51 #if !GLIB_CHECK_VERSION(2, 31, 0) 52 /* before glib-2.31, GMutex and GCond was dynamic-only (there was a separate 53 * GStaticMutex, but it didn't work with condition variables). 54 * 55 * Our implementation uses GOnce to fake a static implementation that does 56 * not require separate initialization. 57 * We need to rename the types to avoid passing our CompatGMutex/CompatGCond 58 * by mistake to a function that expects GMutex/GCond. However, for ease 59 * of use we keep the GLib function names. GLib uses macros for the 60 * implementation, we use inline functions instead and undefine the macros. 61 */ 62 63 typedef struct CompatGMutex { 64 GOnce once; 65 } CompatGMutex; 66 67 typedef struct CompatGCond { 68 GOnce once; 69 } CompatGCond; 70 71 static inline gpointer do_g_mutex_new(gpointer unused) 72 { 73 return (gpointer) g_mutex_new(); 74 } 75 76 static inline void g_mutex_init(CompatGMutex *mutex) 77 { 78 mutex->once = (GOnce) G_ONCE_INIT; 79 } 80 81 static inline void g_mutex_clear(CompatGMutex *mutex) 82 { 83 g_assert(mutex->once.status != G_ONCE_STATUS_PROGRESS); 84 if (mutex->once.retval) { 85 g_mutex_free((GMutex *) mutex->once.retval); 86 } 87 mutex->once = (GOnce) G_ONCE_INIT; 88 } 89 90 static inline void (g_mutex_lock)(CompatGMutex *mutex) 91 { 92 g_once(&mutex->once, do_g_mutex_new, NULL); 93 g_mutex_lock((GMutex *) mutex->once.retval); 94 } 95 #undef g_mutex_lock 96 97 static inline gboolean (g_mutex_trylock)(CompatGMutex *mutex) 98 { 99 g_once(&mutex->once, do_g_mutex_new, NULL); 100 return g_mutex_trylock((GMutex *) mutex->once.retval); 101 } 102 #undef g_mutex_trylock 103 104 105 static inline void (g_mutex_unlock)(CompatGMutex *mutex) 106 { 107 g_mutex_unlock((GMutex *) mutex->once.retval); 108 } 109 #undef g_mutex_unlock 110 111 static inline gpointer do_g_cond_new(gpointer unused) 112 { 113 return (gpointer) g_cond_new(); 114 } 115 116 static inline void g_cond_init(CompatGCond *cond) 117 { 118 cond->once = (GOnce) G_ONCE_INIT; 119 } 120 121 static inline void g_cond_clear(CompatGCond *cond) 122 { 123 g_assert(cond->once.status != G_ONCE_STATUS_PROGRESS); 124 if (cond->once.retval) { 125 g_cond_free((GCond *) cond->once.retval); 126 } 127 cond->once = (GOnce) G_ONCE_INIT; 128 } 129 130 static inline void (g_cond_wait)(CompatGCond *cond, CompatGMutex *mutex) 131 { 132 g_assert(mutex->once.status != G_ONCE_STATUS_PROGRESS); 133 g_once(&cond->once, do_g_cond_new, NULL); 134 g_cond_wait((GCond *) cond->once.retval, (GMutex *) mutex->once.retval); 135 } 136 #undef g_cond_wait 137 138 static inline void (g_cond_broadcast)(CompatGCond *cond) 139 { 140 g_once(&cond->once, do_g_cond_new, NULL); 141 g_cond_broadcast((GCond *) cond->once.retval); 142 } 143 #undef g_cond_broadcast 144 145 static inline void (g_cond_signal)(CompatGCond *cond) 146 { 147 g_once(&cond->once, do_g_cond_new, NULL); 148 g_cond_signal((GCond *) cond->once.retval); 149 } 150 #undef g_cond_signal 151 152 153 /* before 2.31 there was no g_thread_new() */ 154 static inline GThread *g_thread_new(const char *name, 155 GThreadFunc func, gpointer data) 156 { 157 GThread *thread = g_thread_create(func, data, TRUE, NULL); 158 if (!thread) { 159 g_error("creating thread"); 160 } 161 return thread; 162 } 163 #else 164 #define CompatGMutex GMutex 165 #define CompatGCond GCond 166 #endif /* glib 2.31 */ 167 168 #endif 169