vo_opengl: hwdec_cuda: Use dynamic loading for cuda functions

This change applies the pattern used in ffmpeg to dynamically load
cuda, to avoid requiring the CUDA SDK at build time.

1 files changed, 63 insertions, 0 deletions

diff --git a/video/out/opengl/cuda_dynamic.c b/video/out/opengl/cuda_dynamic.c
new file mode 100644
index 0000000000..112e81a521
--- /dev/null
+++ b/video/out/opengl/cuda_dynamic.c
@@ -0,0 +1,63 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "cuda_dynamic.h"
+
+#include <pthread.h>
+
+#if defined(_WIN32)
+# include <windows.h>
+# define dlopen(filename, flags) LoadLibrary(TEXT(filename))
+# define dlsym(handle, symbol) GetProcAddress(handle, symbol)
+# define dlclose(handle) FreeLibrary(handle)
+#else
+# include <dlfcn.h>
+#endif
+
+#if defined(_WIN32) || defined(__CYGWIN__)
+# define CUDA_LIBNAME "nvcuda.dll"
+#else
+# define CUDA_LIBNAME "libcuda.so.1"
+#endif
+
+#define CUDA_DECL(NAME, TYPE) \
+    TYPE *NAME;
+CUDA_FNS(CUDA_DECL)
+
+static bool cuda_loaded = false;
+static pthread_once_t cuda_load_once = PTHREAD_ONCE_INIT;
+
+static void cuda_do_load(void)
+{
+    void *lib = dlopen(CUDA_LIBNAME, RTLD_LAZY);
+    if (!lib) {
+        return;
+    }
+
+#define CUDA_LOAD_SYMBOL(NAME, TYPE) \
+    NAME = dlsym(lib, #NAME); if (!NAME) return;
+
+    CUDA_FNS(CUDA_LOAD_SYMBOL)
+
+    cuda_loaded = true;
+}
+
+bool cuda_load(void)
+{
+    pthread_once(&cuda_load_once, cuda_do_load);
+    return cuda_loaded;
+}