Add emscripten_sleep() wrapper to libc-emcc (#3669)

Author: bnason-nf

core/iwasm/libraries/libc-emcc/libc_emcc_wrapper.c

@@ -495,6 +495,24 @@ emscripten_notify_memory_growth_wrapper(wasm_exec_env_t exec_env, int i)
     (void)i;
 }
 
+static void
+emscripten_sleep_wrapper(wasm_exec_env_t exec_env, int timeout_ms)
+{
+    unsigned int sec;
+    useconds_t us;
+
+    if (timeout_ms <= 0)
+        return;
+
+    sec = timeout_ms / 1000;
+    us = (timeout_ms % 1000) * 1000;
+
+    if (sec > 0)
+        sleep(sec);
+    if (us > 0)
+        usleep(us);
+}
+
 static void
 emscripten_thread_sleep_wrapper(wasm_exec_env_t exec_env, double timeout_ms)
 {
@@ -544,6 +562,7 @@ static NativeSymbol native_symbols_libc_emcc[] = {
     REG_NATIVE_FUNC(__sys_getcwd, "(*~)i"),
     REG_NATIVE_FUNC(__sys_uname, "(*)i"),
     REG_NATIVE_FUNC(emscripten_notify_memory_growth, "(i)"),
+    REG_NATIVE_FUNC(emscripten_sleep, "(i)"),
     REG_NATIVE_FUNC(emscripten_thread_sleep, "(F)"),
 #endif /* end of BH_PLATFORM_LINUX_SGX */
 };