ci+fix: UCRT time functions on Windows; skip libsnappy on MinGW; NUL-terminated names in the mt test

- timeformat node: localtime_s/gmtime_s (reversed args, 64-bit time_t)
  on Windows — MinGW has no localtime_r/gmtime_r
- the multithread suite test passed non-NUL-terminated property names
  (str::as_ptr) to the C property suite — UB that resolved to garbage
  lookups on the CI runner
- libsnappy off on the MinGW FFmpeg build (only feeds the hap encoder;
  its pkg-config entry does not reach the static link)

crates/oaknode/src/nodes/timeformat.rs

@@ -67,11 +67,18 @@ struct Tm {
 
 // `localtime_r` / `gmtime_r` (C `time.h`). Declared locally instead of
 // pulling in a libc crate; both symbols live in the platform C library
-// that `std` already links.
+// that `std` already links. Windows (UCRT) has the `_s` variants with
+// reversed argument order and a 64-bit time_t.
+#[cfg(not(target_os = "windows"))]
 extern "C" {
 	fn localtime_r(timep: *const c_long, result: *mut Tm) -> *mut Tm;
 	fn gmtime_r(timep: *const c_long, result: *mut Tm) -> *mut Tm;
 }
+#[cfg(target_os = "windows")]
+extern "C" {
+	fn localtime_s(result: *mut Tm, timep: *const i64) -> i32;
+	fn gmtime_s(result: *mut Tm, timep: *const i64) -> i32;
+}
 
 /// Expand Qt date/time format tokens (`QDateTime::toString` syntax):
 /// the field tokens d/dd, M/MM, yy/yyyy, h/hh, H/HH, m/mm, s/ss, z/zz/zzz,
@@ -287,6 +294,7 @@ impl NodeBehavior for TimeFormatNode {
 		let ms = (ms_since_epoch % 1000) as i32;
 
 		let mut tm: Tm = unsafe { std::mem::zeroed() };
+		#[cfg(not(target_os = "windows"))]
 		unsafe {
 			if to_bool(&local_val) {
 				localtime_r(&secs, &mut tm);
@@ -294,6 +302,15 @@ impl NodeBehavior for TimeFormatNode {
 				gmtime_r(&secs, &mut tm);
 			}
 		}
+		#[cfg(target_os = "windows")]
+		unsafe {
+			let secs64 = secs as i64;
+			if to_bool(&local_val) {
+				localtime_s(&mut tm, &secs64);
+			} else {
+				gmtime_s(&mut tm, &secs64);
+			}
+		}
 
 		let output = format_date_time(&tm, ms, &to_text(&format_val));
 		table.push(crate::value::ValueType::Text, NodeValue::Text(output), None);

crates/oakplugin/tests/suites_test.rs

@@ -743,14 +743,16 @@ fn multithread_suite_spawned_callbacks() {
 		assert_eq!((s.multi_thread)(counter_worker, 8, raw as *mut c_void), OK);
 	}
 	for i in 0..8 {
-		let name = Box::leak(format!("ctr{i}").into_boxed_str());
+		// C 侧按 NUL 结尾读名字——必须经 cs() 包成 CString（裸
+		// `str::as_ptr()` 不带 NUL，CStr::from_ptr 会读越界）。
+		let name = cs(&format!("ctr{i}"));
 		let mut v = 0;
-		// 注意 `&*set`（Arc 负载）而非 `&set`（Arc 结构体）。
+		// 注意传 `&*set`（Arc 负载）而非 `&set`（Arc 结构体）。
 		unsafe {
 			assert_eq!(
 				(ps.get_int)(
 					&*set as *const _ as *mut c_void,
-					name.as_ptr() as *const c_char,
+					name.as_ptr(),
 					0,
 					&mut v
 				),

tooling/ffmpeg/build-ffmpeg.sh

@@ -139,12 +139,12 @@ if [ -d /opt/homebrew/lib/pkgconfig/openjpeg ]; then
 fi
 enable_if_pkg libopenjp2 libopenjpeg
 # openh264 is redundant for us (decode: FFmpeg's native h264; encode:
-# x264) and its MinGW package does not satisfy the static link — skip it
-# on Windows.
+# x264) and snappy only feeds the hap encoder; neither MinGW package
+# satisfies the static link — skip both on Windows.
 if [ -z "${MSYSTEM:-}" ]; then
 	enable_if_pkg openh264 libopenh264
+	enable_if_pkg snappy libsnappy
 fi
-enable_if_pkg snappy libsnappy
 enable_if_pkg wavpack libwavpack
 enable_if_pkg webp libwebp
 enable_if_pkg xvid libxvid