1 files changed, 73 insertions, 0 deletions
diff --git a/src/nosleep.c b/src/nosleep.c
new file mode 100644
index 0000000..db206e0
--- /dev/null
+++ b/src/nosleep.c
@@ -0,0 +1,73 @@
+/*
+ * Copyright © 2022 Michael Smith <mikesmiffy128@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdbool.h>
+
+#include "con_.h"
+#include "hook.h"
+#include "factory.h"
+#include "gamedata.h"
+#include "os.h"
+#include "vcall.h"
+
+DEF_CVAR_UNREG(engine_no_focus_sleep,
+		"Delay while tabbed out (SST reimplementation)", 50,
+		CON_ARCHIVE | CON_HIDDEN)
+
+static void **vtable;
+
+typedef void (*VCALLCONV SleepUntilInput_func)(void *this, int timeout);
+static SleepUntilInput_func orig_SleepUntilInput;
+static void VCALLCONV hook_SleepUntilInput(void *this, int timeout) {
+	orig_SleepUntilInput(this, con_getvari(engine_no_focus_sleep));
+}
+
+bool nosleep_init(void) {
+	struct con_var *v = con_findvar("engine_no_focus_sleep");
+	if (v) return false; // no need!
+	con_reg(engine_no_focus_sleep);
+	// TODO(featgen): auto-check these factories
+	if (!factory_inputsystem) {
+		con_warn("nosleep: missing required factories\n");
+		return false;
+	}
+	if (!gamedata_has_vtidx_SleepUntilInput) {
+		con_warn("nosleep: missing gamedata entries for this engine\n");
+		return false;
+	}
+	void *insys = factory_inputsystem("InputSystemVersion001", 0);
+	if (!insys) {
+		con_warn("nosleep: couldn't get intput system interface\n");
+		return false;
+	}
+	vtable = *(void ***)insys;
+	if (!os_mprot(vtable + gamedata_vtidx_SleepUntilInput,
+			sizeof(void *), PAGE_EXECUTE_READWRITE)) {
+		con_warn("nosleep: couldn't make memory writeable\n");
+		return false;
+	}
+	orig_SleepUntilInput = (SleepUntilInput_func)hook_vtable(vtable,
+			gamedata_vtidx_SleepUntilInput, (void *)&hook_SleepUntilInput);
+	engine_no_focus_sleep->base.flags &= ~CON_HIDDEN;
+	return true;
+}
+
+void nosleep_end(void) {
+	unhook_vtable(vtable, gamedata_vtidx_SleepUntilInput,
+			(void *)orig_SleepUntilInput);
+}
+
+// vi: sw=4 ts=4 noet tw=80 cc=80