osdep: drop atomic fallback

DOCS/tech-overview.txt

@@ -434,8 +434,7 @@ See generally available literature. In mpv, we use pthread for this.
 
 Always keep locking clean. Don't skip locking just because it will work "in
 practice". (See undefined behavior section.) If your use case is simple, you may
-use C11 atomics (osdep/atomic.h for partial C99 support), but most likely you
-will only hurt yourself and others.
+use C11 atomics, but most likely you will only hurt yourself and others.
 
 Always make clear which fields in a struct are protected by which lock. If a
 field is immutable, or simply not thread-safe (e.g. state for a single worker

audio/out/ao_coreaudio_chmap.h

@@ -20,6 +20,8 @@
 
 #include <AudioToolbox/AudioToolbox.h>
 
+#include "config.h"
+
 struct mp_chmap;
 
 int ca_label_to_mp_speaker_id(AudioChannelLabel label);

audio/out/ao_coreaudio_exclusive.c

@@ -34,6 +34,8 @@
  * when you are wanting to do good buffering of audio).
  */
 
+#include <stdatomic.h>
+
 #include <CoreAudio/HostTime.h>
 
 #include <libavutil/intreadwrite.h>
@@ -43,7 +45,6 @@
 #include "internal.h"
 #include "audio/format.h"
 #include "osdep/timer.h"
-#include "osdep/atomic.h"
 #include "options/m_option.h"
 #include "common/msg.h"
 #include "audio/out/ao_coreaudio_chmap.h"

audio/out/ao_coreaudio_utils.h

@@ -22,6 +22,8 @@
 #include <AudioToolbox/AudioToolbox.h>
 #include <inttypes.h>
 #include <stdbool.h>
+
+#include "config.h"
 #include "common/msg.h"
 #include "audio/out/ao.h"
 #include "internal.h"

audio/out/ao_jack.c

@@ -22,6 +22,7 @@
  * with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stdatomic.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -33,7 +34,6 @@
 #include "ao.h"
 #include "internal.h"
 #include "audio/format.h"
-#include "osdep/atomic.h"
 #include "osdep/timer.h"
 #include "options/m_config.h"
 #include "options/m_option.h"

audio/out/ao_wasapi.h

@@ -20,16 +20,17 @@
 #ifndef MP_AO_WASAPI_H_
 #define MP_AO_WASAPI_H_
 
+#include <stdatomic.h>
 #include <stdlib.h>
 #include <stdbool.h>
+
 #include <windows.h>
 #include <mmdeviceapi.h>
 #include <audioclient.h>
 #include <audiopolicy.h>
 #include <endpointvolume.h>
 
 #include "common/msg.h"
-#include "osdep/atomic.h"
 #include "osdep/windows_utils.h"
 #include "internal.h"
 #include "ao.h"

audio/out/internal.h

@@ -18,10 +18,10 @@
 #ifndef MP_AO_INTERNAL_H_
 #define MP_AO_INTERNAL_H_
 
-#include <stdbool.h>
 #include <pthread.h>
+#include <stdatomic.h>
+#include <stdbool.h>
 
-#include "osdep/atomic.h"
 #include "audio/out/ao.h"
 
 /* global data used by ao.c and ao drivers */
@@ -63,7 +63,7 @@ struct ao {
     atomic_uint events_;
 
     // Float gain multiplicator
-    mp_atomic_float gain;
+    _Atomic float gain;
 
     int buffer;
     double def_buffer;

common/msg.c

@@ -15,19 +15,19 @@
  * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <assert.h>
+#include <pthread.h>
+#include <stdarg.h>
+#include <stdatomic.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdarg.h>
 #include <string.h>
 #include <unistd.h>
-#include <assert.h>
-#include <pthread.h>
-#include <stdint.h>
 
 #include "mpv_talloc.h"
 
 #include "misc/bstr.h"
-#include "osdep/atomic.h"
 #include "common/common.h"
 #include "common/global.h"
 #include "misc/bstr.h"
@@ -524,7 +524,7 @@ void mp_msg_init(struct mpv_global *global)
     struct mp_log_root *root = talloc_zero(NULL, struct mp_log_root);
     *root = (struct mp_log_root){
         .global = global,
-        .reload_counter = ATOMIC_VAR_INIT(1),
+        .reload_counter = 1,
     };
 
     pthread_mutex_init(&root->lock, NULL);

common/stats.c

@@ -1,4 +1,5 @@
 #include <pthread.h>
+#include <stdatomic.h>
 #include <time.h>
 #include <unistd.h>
 
@@ -8,7 +9,6 @@
 #include "misc/node.h"
 #include "msg.h"
 #include "options/m_option.h"
-#include "osdep/atomic.h"
 #include "osdep/timer.h"
 #include "stats.h"
 

demux/demux.c

@@ -15,15 +15,16 @@
  * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <assert.h>
 #include <float.h>
+#include <limits.h>
+#include <pthread.h>
+#include <stdatomic.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <assert.h>
 #include <unistd.h>
-#include <limits.h>
-#include <pthread.h>
-#include <stdint.h>
 
 #include <math.h>
 
@@ -42,7 +43,6 @@
 #include "common/stats.h"
 #include "misc/charset_conv.h"
 #include "misc/thread_tools.h"
-#include "osdep/atomic.h"
 #include "osdep/timer.h"
 #include "osdep/threads.h"
 

filters/f_async_queue.c

@@ -1,10 +1,10 @@
 #include <limits.h>
 #include <pthread.h>
+#include <stdatomic.h>
 
 #include "audio/aframe.h"
 #include "common/common.h"
 #include "common/msg.h"
-#include "osdep/atomic.h"
 
 #include "f_async_queue.h"
 #include "filter_internal.h"
@@ -16,7 +16,7 @@ struct mp_async_queue {
 };
 
 struct async_queue {
-    mp_atomic_uint64 refcount;
+    _Atomic uint64_t refcount;
 
     pthread_mutex_t lock;
 
@@ -73,7 +73,7 @@ struct mp_async_queue *mp_async_queue_create(void)
     struct mp_async_queue *r = talloc_zero(NULL, struct mp_async_queue);
     r->q = talloc_zero(NULL, struct async_queue);
     *r->q = (struct async_queue){
-        .refcount = ATOMIC_VAR_INIT(1),
+        .refcount = 1,
     };
     pthread_mutex_init(&r->q->lock, NULL);
     talloc_set_destructor(r, on_free_queue);

filters/filter.c

@@ -1,12 +1,12 @@
 #include <math.h>
 #include <pthread.h>
+#include <stdatomic.h>
 
 #include <libavutil/hwcontext.h>
 
 #include "common/common.h"
 #include "common/global.h"
 #include "common/msg.h"
-#include "osdep/atomic.h"
 #include "osdep/timer.h"
 #include "video/hwdec.h"
 #include "video/img_format.h"

meson.build

@@ -333,6 +333,9 @@ if features['libdl']
     dependencies += libdl
 endif
 
+# C11 atomics are mandatory but linking to the library is not always required.
+dependencies += cc.find_library('atomic', required: false)
+
 cplugins = get_option('cplugins').require(
     win32 or (features['libdl'] and cc.has_link_argument('-rdynamic')),
     error_message: 'cplugins not supported by the os or compiler!',
@@ -732,13 +735,6 @@ if features['sdl2-gamepad']
     sources += files('input/sdl_gamepad.c')
 endif
 
-stdatomic_dep = cc.find_library('atomic', required: false)
-features += {'stdatomic': cc.has_header_symbol('stdatomic.h', 'atomic_int', dependencies: stdatomic_dep,
-                                               required: get_option('stdatomic'))}
-if features['stdatomic']
-    dependencies += stdatomic_dep
-endif
-
 uchardet_opt = get_option('uchardet').require(
     features['iconv'],
     error_message: 'iconv was not found!',

meson_options.txt

@@ -30,7 +30,6 @@ option('pthread-debug', type: 'feature', value: 'disabled', description: 'pthrea
 option('rubberband', type: 'feature', value: 'auto', description: 'librubberband support')
 option('sdl2', type: 'feature', value: 'disabled', description: 'SDL2')
 option('sdl2-gamepad', type: 'feature', value: 'auto', description: 'SDL2 gamepad input')
-option('stdatomic', type: 'feature', value: 'auto', description: 'C11 stdatomic.h')
 option('uchardet', type: 'feature', value: 'auto', description: 'uchardet support')
 option('uwp', type: 'feature', value: 'disabled', description: 'Universal Windows Platform')
 option('vapoursynth', type: 'feature', value: 'auto', description: 'VapourSynth filter bridge')

misc/thread_tools.c

@@ -14,10 +14,11 @@
  */
 
 #include <assert.h>
+#include <errno.h>
+#include <stdatomic.h>
 #include <string.h>
 #include <sys/types.h>
 #include <unistd.h>
-#include <errno.h>
 
 #ifdef __MINGW32__
 #include <windows.h>
@@ -27,7 +28,6 @@
 
 #include "common/common.h"
 #include "misc/linked_list.h"
-#include "osdep/atomic.h"
 #include "osdep/io.h"
 #include "osdep/timer.h"
 
@@ -126,7 +126,7 @@ struct mp_cancel *mp_cancel_new(void *talloc_ctx)
     struct mp_cancel *c = talloc_ptrtype(talloc_ctx, c);
     talloc_set_destructor(c, cancel_destroy);
     *c = (struct mp_cancel){
-        .triggered = ATOMIC_VAR_INIT(false),
+        .triggered = false,
         .wakeup_pipe = {-1, -1},
     };
     pthread_mutex_init(&c->lock, NULL);

options/m_config_core.c

@@ -15,14 +15,15 @@
  * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdlib.h>
-#include <stdio.h>
+#include <assert.h>
 #include <errno.h>
+#include <pthread.h>
+#include <stdatomic.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <strings.h>
-#include <assert.h>
-#include <stdbool.h>
-#include <pthread.h>
 
 #include "m_config_core.h"
 #include "options/m_option.h"
@@ -31,13 +32,12 @@
 #include "common/msg.h"
 #include "common/msg_control.h"
 #include "misc/dispatch.h"
-#include "osdep/atomic.h"
 
 // For use with m_config_cache.
 struct m_config_shadow {
     pthread_mutex_t lock;
     // Incremented on every option change.
-    mp_atomic_uint64 ts;
+    _Atomic uint64_t ts;
     // -- immutable after init
     // List of m_sub_options instances.
     // Index 0 is the top-level and is always present.

options/m_config_frontend.c

@@ -15,15 +15,16 @@
  * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <assert.h>
+#include <errno.h>
 #include <float.h>
-#include <stdlib.h>
+#include <pthread.h>
+#include <stdatomic.h>
+#include <stdbool.h>
 #include <stdio.h>
-#include <errno.h>
+#include <stdlib.h>
 #include <string.h>
 #include <strings.h>
-#include <assert.h>
-#include <stdbool.h>
-#include <pthread.h>
 
 #include "libmpv/client.h"
 
@@ -36,7 +37,6 @@
 #include "common/msg_control.h"
 #include "misc/dispatch.h"
 #include "misc/node.h"
-#include "osdep/atomic.h"
 
 extern const char mp_help_text[];
 

options/m_config_frontend.h

@@ -17,9 +17,10 @@
 
 #pragma once
 
+#include <stdatomic.h>
+#include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
-#include <stdbool.h>
 
 #include "common/common.h"
 #include "common/global.h"
@@ -29,7 +30,6 @@
 #include "misc/bstr.h"
 #include "misc/dispatch.h"
 #include "options/m_option.h"
-#include "osdep/atomic.h"
 
 // m_config provides an API to manipulate the config variables in MPlayer.
 // It makes use of the Options API to provide a context stack that