From e9e7cce0cdbd50afa6db7748546d76f0280c1756 Mon Sep 17 00:00:00 2001 From: Jeffy Chen Date: Tue, 18 Sep 2018 11:32:04 +0800 Subject: [PATCH] halt: Support rebooting with arg Support passing reboot arg(e.g. loader, fastboot, etc.) to kernel. Signed-off-by: Jeffy Chen --- init/halt.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/init/halt.c b/init/halt.c index f69b897..523c925 100644 --- a/init/halt.c +++ b/init/halt.c @@ -83,6 +83,8 @@ #include "libbb.h" #include "reboot.h" +#include +#include #if ENABLE_FEATURE_WTMP #include @@ -109,6 +111,47 @@ static void write_wtmp(void) #define write_wtmp() ((void)0) #endif +static volatile int caught_sigterm = FALSE; +static void signal_handler(int sig) +{ + bb_error_msg("Caught signal %d", sig); + + if (sig == SIGTERM) + caught_sigterm = TRUE; +} + +static int reboot_with_arg(const char *arg) +{ + struct sigaction sa; + int pid; + + /* Fork new thread to handle reboot */ + if ((pid = fork())) + return pid < 0 ? pid : 0; + + /* Handle signal and reboot in child thread */ + sigemptyset(&sa.sa_mask); + sa.sa_flags = 0; + sa.sa_handler = signal_handler; + sigaction_set(SIGTERM, &sa); + + bb_error_msg("Waiting for SIGTERM"); + + /* The init will send SIGTERM to us after SHUTDOWN actions */ + while (!caught_sigterm) + usleep(50000); + + bb_error_msg("Ready to reboot"); + + /* Wait 200ms for other processes to exit */ + usleep(200000); + sync(); + + bb_error_msg("Rebooting with arg(%s)", arg); + return syscall(__NR_reboot, LINUX_REBOOT_MAGIC1, + LINUX_REBOOT_MAGIC2, + LINUX_REBOOT_CMD_RESTART2, arg); +} int halt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int halt_main(int argc UNUSED_PARAM, char **argv) @@ -186,6 +229,11 @@ int halt_main(int argc UNUSED_PARAM, char **argv) CONFIG_TELINIT_PATH); } } + + /* Handle rebooting with arg */ + if (signals[which] == SIGTERM && argc > 1 && argv[1][0] != '-') + rc = reboot_with_arg(argv[1]); + } else { rc = reboot(magic[which]); } -- 2.11.0