When restartinig in --wait mode, an interrupt to the coordinator
translates to a signal to the root task. This patch fixes and
imrpoves the interface and logic of sending such signals.
Signed-off-by: Oren Laadan <orenl@xxxxxxxxxxxxxxx>
---
restart.c | 132 ++++++++++++++++++++++++++++++++++++++++++++++++++-----------
1 files changed, 109 insertions(+), 23 deletions(-)
diff --git a/restart.c b/restart.c
index fbcc299..a25aaa9 100644
--- a/restart.c
+++ b/restart.c
@@ -58,21 +58,22 @@ static char usage_str[] =
"usage: restart [opts]\n"
" restart restores from a checkpoint image by first creating in userspace\n"
" the original tasks tree, and then calling sys_restart by each task.\n"
-"\tOptions:\n"
-"\t -h,--help print this help message\n"
-"\t -p,--pidns create a new pid namspace (default with --pids)\n"
-"\t -P,--no-pidns do not create a new pid namspace (default)\n"
-"\t --pidns-intr=SIG send SIG to root task on SIGINT (default: SIGKILL)\n"
-"\t --pids restore original pids (default with --pidns)\n"
-"\t -i,--inspect inspect image on-the-fly for error records\n"
-"\t -r,--root=ROOT restart under the directory ROOT instead of current\n"
-"\t -w,--wait wait for (root) task to termiate (default)\n"
-"\t --show-status show exit status of (root) task (implies -w)\n"
-"\t --copy-status imitate exit status of (root) task (implies -w)\n"
-"\t -W,--no-wait do not wait for (root) task to terminate\n"
-"\t -F,--freezer=CGROUP freeze tasks in freezer group CGROUP on success\n"
-"\t -v,--verbose verbose output\n"
-"\t -d,--debug debugging output\n"
+"Options:\n"
+" -h,--help print this help message\n"
+" -p,--pidns create a new pid namspace (default with --pids)\n"
+" -P,--no-pidns do not create a new pid namespace (default)\n"
+" --pids restore original pids (default with --pidns)\n"
+" -i,--inspect inspect image on-the-fly for error records\n"
+" -r,--root=ROOT restart under the directory ROOT instead of current\n"
+" --signal=SIG send SIG to root task on SIGINT (default: SIGKILL\n"
+" to container root, SIGINT otherwise)\n"
+" -w,--wait wait for root task to termiate (default)\n"
+" --show-status show exit status of root task (implies -w)\n"
+" --copy-status imitate exit status of root task (implies -w)\n"
+" -W,--no-wait do not wait for root task to terminate\n"
+" -F,--freezer=CGROUP freeze tasks in freezer group CGROUP on success\n"
+" -v,--verbose verbose output\n"
+" -d,--debug debugging output\n"
"";
/*
@@ -128,6 +129,69 @@ static char usage_str[] =
printf(__VA_ARGS__); \
} while(0)
+#define SIGNAL_ENTRY(signal) { SIG ## signal, #signal }
+
+struct {
+ int signum;
+ char *sigstr;
+} signal_array[] = {
+ { 0, "NONE" },
+ SIGNAL_ENTRY(ALRM),
+ SIGNAL_ENTRY(HUP),
+ SIGNAL_ENTRY(INT),
+ SIGNAL_ENTRY(KILL),
+ SIGNAL_ENTRY(PIPE),
+ SIGNAL_ENTRY(POLL),
+ SIGNAL_ENTRY(PROF),
+ SIGNAL_ENTRY(TERM),
+ SIGNAL_ENTRY(USR1),
+ SIGNAL_ENTRY(USR2),
+ SIGNAL_ENTRY(VTALRM),
+ SIGNAL_ENTRY(STKFLT),
+ SIGNAL_ENTRY(PWR),
+ SIGNAL_ENTRY(WINCH),
+ SIGNAL_ENTRY(CHLD),
+ SIGNAL_ENTRY(URG),
+ SIGNAL_ENTRY(TTIN),
+ SIGNAL_ENTRY(TTOU),
+ SIGNAL_ENTRY(STOP),
+ SIGNAL_ENTRY(CONT),
+ SIGNAL_ENTRY(ABRT),
+ SIGNAL_ENTRY(FPE),
+ SIGNAL_ENTRY(ILL),
+ SIGNAL_ENTRY(QUIT),
+ SIGNAL_ENTRY(SEGV),
+ SIGNAL_ENTRY(TRAP),
+ SIGNAL_ENTRY(SYS),
+ SIGNAL_ENTRY(BUS),
+ SIGNAL_ENTRY(XCPU),
+ SIGNAL_ENTRY(XFSZ),
+ { -1, "LAST" },
+};
+
+static char *sig2str(int sig)
+{
+ int i = 0;
+
+ do {
+ if (signal_array[i].signum == sig)
+ return signal_array[i].sigstr;
+ } while (signal_array[++i].signum >= 0);
+ return "UNKNOWN SIGNAL";
+}
+
+static int str2sig(char *str)
+{
+ int sig = 0;
+
+ do {
+ if (!strcmp(signal_array[sig].sigstr, str))
+ return signal_array[sig].signum;
+ } while (signal_array[++sig].signum >= 0);
+
+ return -1;
+}
+
inline static int restart(pid_t pid, int fd, unsigned long flags)
{
return syscall(__NR_restart, pid, fd, flags);
@@ -287,14 +351,26 @@ static void usage(char *str)
exit(1);
}
+/* negative retval means error */
+static int str2num(char *str)
+{
+ char *nptr;
+ int num;
+
+ num = strtol(str, &nptr, 10);
+ if (nptr - str != strlen(str))
+ num = -1;
+ return num;
+}
+
static void parse_args(struct args *args, int argc, char *argv[])
{
static struct option opts[] = {
{ "help", no_argument, NULL, 'h' },
{ "pidns", no_argument, NULL, 'p' },
- { "pidns-signal", required_argument, NULL, '4' },
{ "no-pidns", no_argument, NULL, 'P' },
{ "pids", no_argument, NULL, 3 },
+ { "signal", required_argument, NULL, 4 },
{ "inspect", no_argument, NULL, 'i' },
{ "root", required_argument, NULL, 'r' },
{ "wait", no_argument, NULL, 'w' },
@@ -336,9 +412,11 @@ static void parse_args(struct args *args, int argc, char *argv[])
args->no_pidns = 1;
break;
case 4:
- sig = atoi(optarg);
+ sig = str2sig(optarg);
+ if (sig < 0)
+ sig = str2num(optarg);
if (sig < 0 || sig >= NSIG) {
- printf("restart: invalid signal number\n");
+ printf("restart: invalid signal\n");
exit(1);
}
global_send_sigint = sig;
@@ -461,13 +539,21 @@ static void sigint_handler(int sig)
{
pid_t pid = global_child_pid;
- ckpt_verbose("SIGINT sent to restarted tasks\n");
+ sig = global_send_sigint;
+ if (!sig) {
+ ckpt_verbose("Interrupt attempt .. ignored.\n");
+ return;
+ }
+
+ ckpt_verbose("Interrupted: sent SIG%s to "
+ "restarted tasks\n", sig2str(sig));
if (pid) {
- ckpt_dbg("delegating SIGINT to child %d "
- "(coordinator or root task)\n", pid);
- kill(-pid, SIGINT);
- kill(pid, SIGINT);
+ ckpt_dbg("delegating SIG%s to child %d "
+ "(coordinator/root task)\n",
+ sig2str(sig), pid);
+ kill(-pid, sig);
+ kill(pid, sig);
}
}
--
1.6.0.4
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