backend: move #ifdefs to nested functions

Instead of littering #ifdefs everywhere, move them to the dedicated
attempt_XXX_backend() functions. This makes the logic in
wlr_backend_autocreate() more readable, and provides better error
messages when the X11/Wayland backends are disabled at compile-time,
or when WLR_BACKENDS contains a backend disabled at compile-time.
This commit is contained in:
Simon Ser 2023-02-27 11:31:07 +01:00
parent 8acaabcbab
commit bec94cc040

View file

@ -70,8 +70,8 @@ void wlr_backend_destroy(struct wlr_backend *backend) {
} }
} }
#if WLR_HAS_SESSION
static struct wlr_session *session_create_and_wait(struct wl_display *disp) { static struct wlr_session *session_create_and_wait(struct wl_display *disp) {
#if WLR_HAS_SESSION
struct wlr_session *session = wlr_session_create(disp); struct wlr_session *session = wlr_session_create(disp);
if (!session) { if (!session) {
@ -109,8 +109,11 @@ static struct wlr_session *session_create_and_wait(struct wl_display *disp) {
} }
return session; return session;
} #else
wlr_log(WLR_ERROR, "Cannot create session: disabled at compile-time");
return NULL;
#endif #endif
}
clockid_t wlr_backend_get_presentation_clock(struct wlr_backend *backend) { clockid_t wlr_backend_get_presentation_clock(struct wlr_backend *backend) {
if (backend->impl->get_presentation_clock) { if (backend->impl->get_presentation_clock) {
@ -164,9 +167,9 @@ static struct wlr_backend *attempt_wl_backend(struct wl_display *display) {
return backend; return backend;
} }
#if WLR_HAS_X11_BACKEND
static struct wlr_backend *attempt_x11_backend(struct wl_display *display, static struct wlr_backend *attempt_x11_backend(struct wl_display *display,
const char *x11_display) { const char *x11_display) {
#if WLR_HAS_X11_BACKEND
struct wlr_backend *backend = wlr_x11_backend_create(display, x11_display); struct wlr_backend *backend = wlr_x11_backend_create(display, x11_display);
if (backend == NULL) { if (backend == NULL) {
return NULL; return NULL;
@ -178,8 +181,11 @@ static struct wlr_backend *attempt_x11_backend(struct wl_display *display,
} }
return backend; return backend;
} #else
wlr_log(WLR_ERROR, "Cannot create X11 backend: disabled at compile-time");
return NULL;
#endif #endif
}
static struct wlr_backend *attempt_headless_backend( static struct wlr_backend *attempt_headless_backend(
struct wl_display *display) { struct wl_display *display) {
@ -196,9 +202,9 @@ static struct wlr_backend *attempt_headless_backend(
return backend; return backend;
} }
#if WLR_HAS_DRM_BACKEND
static bool attempt_drm_backend(struct wl_display *display, static bool attempt_drm_backend(struct wl_display *display,
struct wlr_backend *backend, struct wlr_session *session) { struct wlr_backend *backend, struct wlr_session *session) {
#if WLR_HAS_DRM_BACKEND
struct wlr_device *gpus[8]; struct wlr_device *gpus[8];
ssize_t num_gpus = wlr_session_find_gpus(session, 8, gpus); ssize_t num_gpus = wlr_session_find_gpus(session, 8, gpus);
if (num_gpus < 0) { if (num_gpus < 0) {
@ -238,8 +244,21 @@ static bool attempt_drm_backend(struct wl_display *display,
} }
return true; return true;
} #else
wlr_log(WLR_ERROR, "Cannot create DRM backend: disabled at compile-time");
return false;
#endif #endif
}
static struct wlr_backend *attempt_libinput_backend(struct wl_display *display,
struct wlr_session *session) {
#if WLR_HAS_LIBINPUT_BACKEND
return wlr_libinput_backend_create(display, session);
#else
wlr_log(WLR_ERROR, "Cannot create libinput backend: disabled at compile-time");
return NULL;
#endif
}
static bool attempt_backend_by_name(struct wl_display *display, static bool attempt_backend_by_name(struct wl_display *display,
struct wlr_backend *multi, char *name, struct wlr_backend *multi, char *name,
@ -247,18 +266,14 @@ static bool attempt_backend_by_name(struct wl_display *display,
struct wlr_backend *backend = NULL; struct wlr_backend *backend = NULL;
if (strcmp(name, "wayland") == 0) { if (strcmp(name, "wayland") == 0) {
backend = attempt_wl_backend(display); backend = attempt_wl_backend(display);
#if WLR_HAS_X11_BACKEND
} else if (strcmp(name, "x11") == 0) { } else if (strcmp(name, "x11") == 0) {
backend = attempt_x11_backend(display, NULL); backend = attempt_x11_backend(display, NULL);
#endif
} else if (strcmp(name, "headless") == 0) { } else if (strcmp(name, "headless") == 0) {
backend = attempt_headless_backend(display); backend = attempt_headless_backend(display);
} else if (strcmp(name, "drm") == 0 || strcmp(name, "libinput") == 0) { } else if (strcmp(name, "drm") == 0 || strcmp(name, "libinput") == 0) {
// DRM and libinput need a session // DRM and libinput need a session
if (*session_ptr == NULL) { if (*session_ptr == NULL) {
#if WLR_HAS_SESSION
*session_ptr = session_create_and_wait(display); *session_ptr = session_create_and_wait(display);
#endif
if (*session_ptr == NULL) { if (*session_ptr == NULL) {
wlr_log(WLR_ERROR, "failed to start a session"); wlr_log(WLR_ERROR, "failed to start a session");
return false; return false;
@ -266,14 +281,10 @@ static bool attempt_backend_by_name(struct wl_display *display,
} }
if (strcmp(name, "libinput") == 0) { if (strcmp(name, "libinput") == 0) {
#if WLR_HAS_LIBINPUT_BACKEND backend = attempt_libinput_backend(display, *session_ptr);
backend = wlr_libinput_backend_create(display, *session_ptr);
#endif
} else { } else {
#if WLR_HAS_DRM_BACKEND // attempt_drm_backend() adds the multi drm backends itself
// attempt_drm_backend adds the multi drm backends itself
return attempt_drm_backend(display, multi, *session_ptr); return attempt_drm_backend(display, multi, *session_ptr);
#endif
} }
} else { } else {
wlr_log(WLR_ERROR, "unrecognized backend '%s'", name); wlr_log(WLR_ERROR, "unrecognized backend '%s'", name);
@ -336,7 +347,6 @@ struct wlr_backend *wlr_backend_autocreate(struct wl_display *display,
goto success; goto success;
} }
#if WLR_HAS_X11_BACKEND
const char *x11_display = getenv("DISPLAY"); const char *x11_display = getenv("DISPLAY");
if (x11_display) { if (x11_display) {
struct wlr_backend *x11_backend = struct wlr_backend *x11_backend =
@ -348,47 +358,30 @@ struct wlr_backend *wlr_backend_autocreate(struct wl_display *display,
wlr_multi_backend_add(multi, x11_backend); wlr_multi_backend_add(multi, x11_backend);
goto success; goto success;
} }
#endif
// Attempt DRM+libinput // Attempt DRM+libinput
#if WLR_HAS_SESSION
session = session_create_and_wait(display); session = session_create_and_wait(display);
#endif
if (!session) { if (!session) {
wlr_log(WLR_ERROR, "Failed to start a DRM session"); wlr_log(WLR_ERROR, "Failed to start a DRM session");
goto error; goto error;
} }
#if WLR_HAS_LIBINPUT_BACKEND struct wlr_backend *libinput = attempt_libinput_backend(display, session);
struct wlr_backend *libinput = if (libinput) {
wlr_libinput_backend_create(display, session);
if (!libinput) {
wlr_log(WLR_ERROR, "Failed to start libinput backend");
goto error;
}
wlr_multi_backend_add(multi, libinput); wlr_multi_backend_add(multi, libinput);
#else } else if (env_parse_bool("WLR_LIBINPUT_NO_DEVICES")) {
if (env_parse_bool("WLR_LIBINPUT_NO_DEVICES")) {
wlr_log(WLR_INFO, "WLR_LIBINPUT_NO_DEVICES is set, " wlr_log(WLR_INFO, "WLR_LIBINPUT_NO_DEVICES is set, "
"starting without libinput backend"); "starting without libinput backend");
} else { } else {
wlr_log(WLR_ERROR, "libinput support is not compiled in, " wlr_log(WLR_ERROR, "Failed to start libinput backend");
"refusing to start"); wlr_log(WLR_ERROR, "Set WLR_LIBINPUT_NO_DEVICES=1 to skip libinput");
wlr_log(WLR_ERROR, "Set WLR_LIBINPUT_NO_DEVICES=1 to suppress this check");
goto error; goto error;
} }
#endif
#if WLR_HAS_DRM_BACKEND
if (!attempt_drm_backend(display, multi, session)) { if (!attempt_drm_backend(display, multi, session)) {
wlr_log(WLR_ERROR, "Failed to open any DRM device"); wlr_log(WLR_ERROR, "Failed to open any DRM device");
goto error; goto error;
} }
#else
wlr_log(WLR_ERROR, "DRM backend support is not compiled in, "
"refusing to start");
goto error;
#endif
success: success:
if (session_ptr != NULL) { if (session_ptr != NULL) {