Fix a crash on systems using musl as libc

Fixes #3395

docs/changelog.rst

@@ -97,6 +97,8 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 
 - Fix inactive tab closing causing active tab to change (:iss:`3398`)
 
+- Fix a crash on systems using musl as libc (:iss:`3395`)
+
 
 0.19.3 [2020-12-19]
 -------------------

glfw/glfw.py

@@ -179,13 +179,12 @@ class Function:
         )
 
     def load(self) -> str:
-        ans = '*(void **) (&{name}_impl) = dlsym(handle, "{name}");'.format(
+        ans = f'*(void **) (&{self.name}_impl) = dlsym(handle, "{self.name}");'
-            name=self.name
+        ans += f'\n    if ({self.name}_impl == NULL) '
-        )
         if self.check_fail:
-            ans += '\n    if ({name}_impl == NULL) fail("Failed to load glfw function {name} with error: %s", dlerror());'.format(
+            ans += f'fail("Failed to load glfw function {self.name} with error: %s", dlerror());'
-                name=self.name
+        else:
-            )
+            ans += 'dlerror(); // clear error indicator'
         return ans
 
 

kitty/desktop.c

@@ -11,9 +11,11 @@
 #define FUNC(name, restype, ...) typedef restype (*name##_func)(__VA_ARGS__); static name##_func name = NULL
 #define LOAD_FUNC(handle, name) {\
     *(void **) (&name) = dlsym(handle, #name); \
-    const char* error = dlerror(); \
+    if (!name) { \
-    if (error != NULL) { \
+        const char* error = dlerror(); \
-        PyErr_Format(PyExc_OSError, "Failed to load the function %s with error: %s", #name, error); dlclose(handle); handle = NULL; return NULL; \
+        if (error != NULL) { \
+            PyErr_Format(PyExc_OSError, "Failed to load the function %s with error: %s", #name, error); dlclose(handle); handle = NULL; return NULL; \
+        } \
     } \
 }
 
@@ -139,6 +141,7 @@ load_libcanberra(void) {
     if (PyErr_Occurred()) {
         PyErr_Print();
         dlclose(libcanberra_handle); libcanberra_handle = NULL;
+        return;
     }
     if (ca_context_create(&canberra_ctx) != 0) {
         fprintf(stderr, "Failed to create libcanberra context, cannot play beep sound\n");

kitty/glfw-wrapper.c

@@ -379,42 +379,61 @@ load_glfw(const char* path) {
     if (glfwGetRequiredInstanceExtensions_impl == NULL) fail("Failed to load glfw function glfwGetRequiredInstanceExtensions with error: %s", dlerror());
 
     *(void **) (&glfwGetCocoaWindow_impl) = dlsym(handle, "glfwGetCocoaWindow");
+    if (glfwGetCocoaWindow_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwHideCocoaTitlebar_impl) = dlsym(handle, "glfwHideCocoaTitlebar");
+    if (glfwHideCocoaTitlebar_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetNSGLContext_impl) = dlsym(handle, "glfwGetNSGLContext");
+    if (glfwGetNSGLContext_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetCocoaMonitor_impl) = dlsym(handle, "glfwGetCocoaMonitor");
+    if (glfwGetCocoaMonitor_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetCocoaTextInputFilter_impl) = dlsym(handle, "glfwSetCocoaTextInputFilter");
+    if (glfwSetCocoaTextInputFilter_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetCocoaFileOpenCallback_impl) = dlsym(handle, "glfwSetCocoaFileOpenCallback");
+    if (glfwSetCocoaFileOpenCallback_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetCocoaToggleFullscreenIntercept_impl) = dlsym(handle, "glfwSetCocoaToggleFullscreenIntercept");
+    if (glfwSetCocoaToggleFullscreenIntercept_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetApplicationShouldHandleReopen_impl) = dlsym(handle, "glfwSetApplicationShouldHandleReopen");
+    if (glfwSetApplicationShouldHandleReopen_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetApplicationWillFinishLaunching_impl) = dlsym(handle, "glfwSetApplicationWillFinishLaunching");
+    if (glfwSetApplicationWillFinishLaunching_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetCocoaKeyEquivalent_impl) = dlsym(handle, "glfwGetCocoaKeyEquivalent");
+    if (glfwGetCocoaKeyEquivalent_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwCocoaRequestRenderFrame_impl) = dlsym(handle, "glfwCocoaRequestRenderFrame");
+    if (glfwCocoaRequestRenderFrame_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetX11Display_impl) = dlsym(handle, "glfwGetX11Display");
+    if (glfwGetX11Display_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetX11Window_impl) = dlsym(handle, "glfwGetX11Window");
+    if (glfwGetX11Window_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwSetPrimarySelectionString_impl) = dlsym(handle, "glfwSetPrimarySelectionString");
+    if (glfwSetPrimarySelectionString_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetPrimarySelectionString_impl) = dlsym(handle, "glfwGetPrimarySelectionString");
+    if (glfwGetPrimarySelectionString_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwGetNativeKeyForName_impl) = dlsym(handle, "glfwGetNativeKeyForName");
+    if (glfwGetNativeKeyForName_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwRequestWaylandFrameEvent_impl) = dlsym(handle, "glfwRequestWaylandFrameEvent");
+    if (glfwRequestWaylandFrameEvent_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwDBusUserNotify_impl) = dlsym(handle, "glfwDBusUserNotify");
+    if (glfwDBusUserNotify_impl == NULL) dlerror(); // clear error indicator
 
     *(void **) (&glfwDBusSetUserNotificationHandler_impl) = dlsym(handle, "glfwDBusSetUserNotificationHandler");
+    if (glfwDBusSetUserNotificationHandler_impl == NULL) dlerror(); // clear error indicator
 
     return NULL;
 }