diff --git a/app/meson.build b/app/meson.build
index f43a6bd6..3482f14c 100644
--- a/app/meson.build
+++ b/app/meson.build
@@ -5,6 +5,7 @@ src = [
     'src/command.c',
     'src/decoder.c',
     'src/frames.c',
+    'src/lockutil.c',
     'src/netutil.c',
     'src/screen.c',
     'src/strutil.c',
diff --git a/app/src/lockutil.c b/app/src/lockutil.c
new file mode 100644
index 00000000..8891e6df
--- /dev/null
+++ b/app/src/lockutil.c
@@ -0,0 +1,32 @@
+#include <stdlib.h>
+#include <SDL2/SDL_log.h>
+#include <SDL2/SDL_mutex.h>
+
+void mutex_lock(SDL_mutex *mutex) {
+    if (SDL_LockMutex(mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not lock mutex");
+        abort();
+    }
+}
+
+void mutex_unlock(SDL_mutex *mutex) {
+    if (SDL_UnlockMutex(mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not unlock mutex");
+        abort();
+    }
+}
+
+void cond_wait(SDL_cond *cond, SDL_mutex *mutex) {
+    if (SDL_CondWait(cond, mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not wait on condition");
+        abort();
+    }
+}
+
+void cond_signal(SDL_cond *cond) {
+    if (SDL_CondSignal(cond)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not signal a condition");
+        abort();
+    }
+}
+
diff --git a/app/src/lockutil.h b/app/src/lockutil.h
index 10a9adf2..255cafe4 100644
--- a/app/src/lockutil.h
+++ b/app/src/lockutil.h
@@ -1,36 +1,13 @@
 #ifndef LOCKUTIL_H
 #define LOCKUTIL_H
 
-#include <stdlib.h>
-#include <SDL2/SDL_log.h>
-#include <SDL2/SDL_mutex.h>
+// forward declarations
+typedef struct SDL_mutex SDL_mutex;
+typedef struct SDL_cond SDL_cond;
 
-static inline void mutex_lock(SDL_mutex *mutex) {
-    if (SDL_LockMutex(mutex)) {
-        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not lock mutex");
-        exit(1);
-    }
-}
-
-static inline void mutex_unlock(SDL_mutex *mutex) {
-    if (SDL_UnlockMutex(mutex)) {
-        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not unlock mutex");
-        exit(1);
-    }
-}
-
-static inline void cond_wait(SDL_cond *cond, SDL_mutex *mutex) {
-    if (SDL_CondWait(cond, mutex)) {
-        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not wait on condition");
-        exit(1);
-    }
-}
-
-static inline void cond_signal(SDL_cond *cond) {
-    if (SDL_CondSignal(cond)) {
-        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not signal a condition");
-        exit(1);
-    }
-}
+void mutex_lock(SDL_mutex *mutex);
+void mutex_unlock(SDL_mutex *mutex);
+void cond_wait(SDL_cond *cond, SDL_mutex *mutex);
+void cond_signal(SDL_cond *cond);
 
 #endif