xref: /qemu/include/glib-compat.h (revision ba4dba54)
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 static inline gboolean (g_cond_timed_wait)(CompatGCond *cond,
153                                            CompatGMutex *mutex,
154                                            GTimeVal *time)
155 {
156     g_assert(mutex->once.status != G_ONCE_STATUS_PROGRESS);
157     g_once(&cond->once, do_g_cond_new, NULL);
158     return g_cond_timed_wait((GCond *) cond->once.retval,
159                              (GMutex *) mutex->once.retval, time);
160 }
161 #undef g_cond_timed_wait
162 
163 /* This is not a macro, because it didn't exist until 2.32.  */
164 static inline gboolean g_cond_wait_until(CompatGCond *cond, CompatGMutex *mutex,
165                                          gint64 end_time)
166 {
167     GTimeVal time;
168 
169     /* Convert from monotonic to CLOCK_REALTIME.  */
170     end_time -= g_get_monotonic_time();
171     g_get_current_time(&time);
172     end_time += time.tv_sec * G_TIME_SPAN_SECOND + time.tv_usec;
173 
174     time.tv_sec = end_time / G_TIME_SPAN_SECOND;
175     time.tv_usec = end_time % G_TIME_SPAN_SECOND;
176     return g_cond_timed_wait(cond, mutex, &time);
177 }
178 
179 /* before 2.31 there was no g_thread_new() */
180 static inline GThread *g_thread_new(const char *name,
181                                     GThreadFunc func, gpointer data)
182 {
183     GThread *thread = g_thread_create(func, data, TRUE, NULL);
184     if (!thread) {
185         g_error("creating thread");
186     }
187     return thread;
188 }
189 #else
190 #define CompatGMutex GMutex
191 #define CompatGCond GCond
192 #endif /* glib 2.31 */
193 
194 #if !GLIB_CHECK_VERSION(2, 32, 0)
195 /* Beware, function returns gboolean since 2.39.2, see GLib commit 9101915 */
196 static inline void g_hash_table_add(GHashTable *hash_table, gpointer key)
197 {
198     g_hash_table_replace(hash_table, key, key);
199 }
200 #endif
201 
202 #ifndef g_assert_true
203 #define g_assert_true(expr)                                                    \
204     do {                                                                       \
205         if (G_LIKELY(expr)) {                                                  \
206         } else {                                                               \
207             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
208                                 "'" #expr "' should be TRUE");                 \
209         }                                                                      \
210     } while (0)
211 #endif
212 
213 #ifndef g_assert_false
214 #define g_assert_false(expr)                                                   \
215     do {                                                                       \
216         if (G_LIKELY(!(expr))) {                                               \
217         } else {                                                               \
218             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
219                                 "'" #expr "' should be FALSE");                \
220         }                                                                      \
221     } while (0)
222 #endif
223 
224 #ifndef g_assert_null
225 #define g_assert_null(expr)                                                    \
226     do {                                                                       \
227         if (G_LIKELY((expr) == NULL)) {                                        \
228         } else {                                                               \
229             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
230                                 "'" #expr "' should be NULL");                 \
231         }                                                                      \
232     } while (0)
233 #endif
234 
235 #ifndef g_assert_nonnull
236 #define g_assert_nonnull(expr)                                                 \
237     do {                                                                       \
238         if (G_LIKELY((expr) != NULL)) {                                        \
239         } else {                                                               \
240             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
241                                 "'" #expr "' should not be NULL");             \
242         }                                                                      \
243     } while (0)
244 #endif
245 
246 #ifndef g_assert_cmpmem
247 #define g_assert_cmpmem(m1, l1, m2, l2)                                        \
248     do {                                                                       \
249         gconstpointer __m1 = m1, __m2 = m2;                                    \
250         int __l1 = l1, __l2 = l2;                                              \
251         if (__l1 != __l2) {                                                    \
252             g_assertion_message_cmpnum(                                        \
253                 G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,                   \
254                 #l1 " (len(" #m1 ")) == " #l2 " (len(" #m2 "))", __l1, "==",   \
255                 __l2, 'i');                                                    \
256         } else if (memcmp(__m1, __m2, __l1) != 0) {                            \
257             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
258                                 "assertion failed (" #m1 " == " #m2 ")");      \
259         }                                                                      \
260     } while (0)
261 #endif
262 
263 #endif
264