- if (!library) {
- library = util_dl_open(DXTN_LIBNAME);
- if (!library) {
- debug_printf("couldn't open " DXTN_LIBNAME ", software DXTn "
- "compression/decompression unavailable");
- }
- else {
- util_format_dxt1_rgb_fetch = (util_format_dxtn_fetch_t)
- util_dl_get_proc_address(library, "fetch_2d_texel_rgb_dxt1");
- util_format_dxt1_rgba_fetch = (util_format_dxtn_fetch_t)
- util_dl_get_proc_address(library, "fetch_2d_texel_rgba_dxt1");
- util_format_dxt3_rgba_fetch = (util_format_dxtn_fetch_t)
- util_dl_get_proc_address(library, "fetch_2d_texel_rgba_dxt3");
- util_format_dxt5_rgba_fetch = (util_format_dxtn_fetch_t)
- util_dl_get_proc_address(library, "fetch_2d_texel_rgba_dxt5");
- util_format_dxtn_pack = (util_format_dxtn_pack_t)
- util_dl_get_proc_address(library, "tx_compress_dxtn");
-
- if (util_format_dxt1_rgb_fetch ||
- util_format_dxt1_rgba_fetch ||
- util_format_dxt3_rgba_fetch ||
- util_format_dxt5_rgba_fetch ||
- util_format_dxtn_pack) {
- util_format_s3tc_enabled = TRUE;
- debug_printf("software DXTn compression/decompression available");
-
- } else {
- debug_printf("couldn't reference all symbols in "
- DXTN_LIBNAME ", software DXTn compression/decompression "
- "unavailable");
- }
- }
+util_format_dxtn_fetch_t util_format_dxt1_rgb_fetch = util_format_dxt1_rgb_fetch_stub;
+util_format_dxtn_fetch_t util_format_dxt1_rgba_fetch = util_format_dxt1_rgba_fetch_stub;
+util_format_dxtn_fetch_t util_format_dxt3_rgba_fetch = util_format_dxt3_rgba_fetch_stub;
+util_format_dxtn_fetch_t util_format_dxt5_rgba_fetch = util_format_dxt5_rgba_fetch_stub;
+
+util_format_dxtn_pack_t util_format_dxtn_pack = util_format_dxtn_pack_stub;
+
+static void
+nop(void)
+{}
+
+#define is_nop(f) ((void*)(f) == (void*)nop)
+
+static util_dl_proc
+get_proc_address_or_nop(struct util_dl_library *library,
+ const char *procname)
+{
+ if(library) {
+ util_dl_proc proc = util_dl_get_proc_address(library, procname);
+ if(proc)
+ return proc;
+ }
+ return (util_dl_proc)nop;
+}
+
+void
+util_format_s3tc_do_init(void)
+{
+ struct util_dl_library *library;
+
+ library = util_dl_open(DXTN_LIBNAME);
+ util_format_dxt1_rgb_fetch = (util_format_dxtn_fetch_t)
+ get_proc_address_or_nop(library, "fetch_2d_texel_rgb_dxt1");
+ util_format_dxt1_rgba_fetch = (util_format_dxtn_fetch_t)
+ get_proc_address_or_nop(library, "fetch_2d_texel_rgba_dxt1");
+ util_format_dxt3_rgba_fetch = (util_format_dxtn_fetch_t)
+ get_proc_address_or_nop(library, "fetch_2d_texel_rgba_dxt3");
+ util_format_dxt5_rgba_fetch = (util_format_dxtn_fetch_t)
+ get_proc_address_or_nop(library, "fetch_2d_texel_rgba_dxt5");
+ util_format_dxtn_pack = (util_format_dxtn_pack_t)
+ get_proc_address_or_nop(library, "tx_compress_dxtn");
+
+ if (!library)
+ debug_printf("couldn't open " DXTN_LIBNAME ", software DXTn "
+ "compression/decompression unavailable");
+ else {
+ if (!is_nop(util_format_dxt1_rgb_fetch) &&
+ !is_nop(util_format_dxt1_rgba_fetch) &&
+ !is_nop(util_format_dxt3_rgba_fetch) &&
+ !is_nop(util_format_dxt5_rgba_fetch) &&
+ !is_nop(util_format_dxtn_pack)) {
+ debug_printf("software DXTn compression/decompression available");
+ util_format_s3tc_enabled = TRUE;
+ } else
+ debug_printf("couldn't reference all symbols in "
+ DXTN_LIBNAME ", software DXTn compression/decompression "
+ "unavailable");