path: root/compat
diff options
authorwm4 <wm4@nowhere>2014-07-05 17:02:06 +0200
committerwm4 <wm4@nowhere>2014-07-05 17:07:16 +0200
commitd27a2bc546a2ba8dcb69931c9a1f7b60a1b95b03 (patch)
treee5a89781003abbc43c72f7387ca9f0146b34048b /compat
parent49df0355148e268a2afbc35f351e3adc05fc22d8 (diff)
build: allow compilation without any atomics
Not all compilers on all platforms have atomics available (even if they could, technically speaking). We don't use atomics that much, only the following things rely on it: 1. the audio pull code, and all audio outputs using it 2. updating global msg levels 3. reading log messages through the client API Just disable 1. and 3. if atomics are not available. For 2., using fake- atomics isn't too bad; at worst, message levels won't properly update under certain situations (but most likely, it will work just fine). This means if atomics are not available, the client API function mpv_request_log_messages() will do nothing. CC: @mpv-player/stable
Diffstat (limited to 'compat')
1 files changed, 13 insertions, 2 deletions
diff --git a/compat/atomics.h b/compat/atomics.h
index 797992f876..e5fb717a78 100644
--- a/compat/atomics.h
+++ b/compat/atomics.h
@@ -22,6 +22,8 @@
#include <inttypes.h>
#include "config.h"
+#define HAVE_ATOMICS 1
#include <stdatomic.h>
@@ -58,8 +60,17 @@ typedef struct { volatile unsigned long long v; } atomic_ullong;
__sync_fetch_and_add(&(a)->v, b)
-# error "this should have been a configuration error, report a bug please"
+// This is extremely wrong. The build system actually disables code that has
+// a serious dependency on working atomics, so this is barely ok.
+#define atomic_load(p) ((p)->v)
+#define atomic_store(p, val) ((p)->v = (val))
+#define atomic_fetch_add(a, b) (((a)->v += (b)) - (b))
+#define HAVE_ATOMICS 0
+#endif /* no atomics */
#endif /* else HAVE_STDATOMIC */