perf(zaparoo): exec launcher directly

Author: asturur

support/zaparoo/alt_launcher.cpp

@@ -68,6 +68,7 @@ uint16_t alt_launcher_fb_terminal_key(uint32_t mask, bool osd_button)
 static pid_t s_pid = 0;
 static int s_crash_count = 0;
 static unsigned long s_respawn_timer = 0;
+static unsigned long s_tty_deadline = 0;
 static unsigned long s_native_status_timer = 0;
 static unsigned long s_native_fb_mode_timer = 0;
 static bool s_gave_up = false;
@@ -254,16 +255,6 @@ static void enable_native_crt_path(void)
 	if (!s_native_fb_mode_timer) s_native_fb_mode_timer = 1;
 }
 
-static void wait_launcher_tty_ready(pid_t pid)
-{
-	for (int i = 0; i < 100; i++)
-	{
-		if (launcher_tty_ready(pid))
-			return;
-		usleep(10000);
-	}
-}
-
 static void return_to_normal_mode(void)
 {
 	user_io_osd_key_enable(1);
@@ -282,6 +273,7 @@ static void reset_launcher_state(void)
 {
 	s_pid = 0;
 	s_respawn_timer = 0;
+	s_tty_deadline = 0;
 	s_crash_count = 0;
 	s_gave_up = false;
 	s_init_pending = false;
@@ -337,26 +329,63 @@ static void release_launcher_video(void)
 	}
 }
 
+static void exec_launcher_child(const char *path)
+{
+	setenv("LC_ALL", "en_US.UTF-8", 1);
+	setenv("HOME", "/root", 1);
+
+	cpu_set_t set;
+	CPU_ZERO(&set);
+	CPU_SET(0, &set);
+	sched_setaffinity(0, sizeof(set), &set);
+
+	setsid();
+
+	int tty_fd = open(s_tty_path, O_RDWR);
+	if (tty_fd >= 0)
+	{
+		ioctl(tty_fd, TIOCSCTTY, 0);
+		dup2(tty_fd, STDIN_FILENO);
+		dup2(tty_fd, STDOUT_FILENO);
+		dup2(tty_fd, STDERR_FILENO);
+		if (tty_fd > STDERR_FILENO)
+			close(tty_fd);
+	}
+
+	static const char clear[] = "\033[0m\033[?25l\033[37m\033[40m\033[2J\033[H";
+	if (write(STDOUT_FILENO, clear, sizeof(clear) - 1) < 0) {}
+
+	if (s_native_crt)
+		execl(path, path, "--crt", NULL);
+	else
+		execl(path, path, NULL);
+	_exit(1);
+}
+
+static void finalize_spawn(void)
+{
+	s_tty_deadline = 0;
+	video_chvt(s_vt);
+	if (!s_native_crt)
+		video_fb_enable(1);
+	else
+	{
+		input_switch(0);
+		user_io_status_set("[9]", 1);
+	}
+
+	// The frontend grabs input as soon as it starts. If the OSD is still
+	// up (e.g. user toggled CRT mode or hit Reboot from System Settings),
+	// it would trap input with no way to dismiss it — drop it now.
+	if (menu_present()) MenuHide();
+}
+
 static void spawn(void)
 {
 	char path[2100];
 	strncpy(path, getFullPath(s_launcher_path), sizeof(path) - 1);
 	path[sizeof(path) - 1] = '\0';
 
-	static const char cmd[] =
-		"#!/bin/bash\n"
-		"export LC_ALL=en_US.UTF-8\n"
-		"export HOME=/root\n"
-		"printf '\\033[0m\\033[?25l\\033[37m\\033[40m\\033[2J\\033[H'\n"
-		"if [ \"$ALT_LAUNCHER_CRT\" = \"1\" ]; then\n"
-		"	exec \"$ALT_LAUNCHER_PATH\" --crt\n"
-		"fi\n"
-		"exec \"$ALT_LAUNCHER_PATH\"\n";
-
-	unlink("/tmp/alt_launcher");
-	if (!FileSave("/tmp/alt_launcher", (void*)cmd, strlen(cmd)))
-		return;
-
 	user_io_osd_key_enable(0);
 	clear_launcher_tty();
 
@@ -384,32 +413,11 @@ static void spawn(void)
 	printf("alt_launcher: spawned pid=%d path=%s\n", s_pid, path);
 	if (!s_pid)
 	{
-		setenv("ALT_LAUNCHER_PATH", path, 1);
-		setenv("ALT_LAUNCHER_CRT", s_native_crt ? "1" : "0", 1);
-		cpu_set_t set;
-		CPU_ZERO(&set);
-		CPU_SET(0, &set);
-		sched_setaffinity(0, sizeof(set), &set);
-		setsid();
-		execl("/sbin/agetty", "/sbin/agetty", "-a", "root", "-l",
-		      "/tmp/alt_launcher", "-i", "--nohostname", "-L", s_tty, "linux", NULL);
-		_exit(1);
-	}
-
-	wait_launcher_tty_ready(s_pid);
-	video_chvt(s_vt);
-	if (!s_native_crt)
-		video_fb_enable(1);
-	else
-	{
-		input_switch(0);
-		user_io_status_set("[9]", 1);
+		exec_launcher_child(path);
 	}
 
-	// The frontend grabs input as soon as it starts. If the OSD is still
-	// up (e.g. user toggled CRT mode or hit Reboot from System Settings),
-	// it would trap input with no way to dismiss it — drop it now.
-	if (menu_present()) MenuHide();
+	s_tty_deadline = GetTimer(1000);
+	if (!s_tty_deadline) s_tty_deadline = 1;
 }
 
 bool alt_launcher_active(void)
@@ -419,7 +427,7 @@ bool alt_launcher_active(void)
 
 bool alt_launcher_scheduler_sleep_enabled(void)
 {
-	return s_pid || s_init_pending || s_respawn_timer;
+	return s_pid || s_init_pending || s_respawn_timer || s_tty_deadline;
 }
 
 bool alt_launcher_native_crt(void)
@@ -474,6 +482,7 @@ void alt_launcher_init(bool native_crt)
 		return;
 	s_crash_count = 0;
 	s_respawn_timer = 0;
+	s_tty_deadline = 0;
 	s_native_crt = native_crt;
 	s_init_pending = true;
 }
@@ -491,6 +500,7 @@ void alt_launcher_prepare_for_script(void)
 	wait_launcher_stopped(pid);
 	user_io_osd_key_enable(1);
 	s_respawn_timer = 0;
+	s_tty_deadline = 0;
 	s_crash_count = 0;
 	s_init_pending = false;
 	s_gave_up = false;
@@ -536,6 +546,7 @@ void alt_launcher_poll(void)
 		if (waitpid(s_pid, &status, WNOHANG) == s_pid)
 		{
 			s_pid = 0;
+			s_tty_deadline = 0;
 			user_io_osd_key_enable(1);
 			bool exited = WIFEXITED(status);
 			int exit_status = exited ? WEXITSTATUS(status) : 0;
@@ -570,7 +581,11 @@ void alt_launcher_poll(void)
 				s_crash_count = 0;
 			s_respawn_timer = GetTimer(1000);
 			if (!s_respawn_timer) s_respawn_timer = 1;
+			return;
 		}
+
+		if (s_tty_deadline && (launcher_tty_ready(s_pid) || CheckTimer(s_tty_deadline)))
+			finalize_spawn();
 		return;
 	}