aboutsummaryrefslogtreecommitdiffstats
path: root/src/plugins/fateshare/vpp_fateshare_monitor.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/plugins/fateshare/vpp_fateshare_monitor.c')
-rw-r--r--src/plugins/fateshare/vpp_fateshare_monitor.c261
1 files changed, 261 insertions, 0 deletions
diff --git a/src/plugins/fateshare/vpp_fateshare_monitor.c b/src/plugins/fateshare/vpp_fateshare_monitor.c
new file mode 100644
index 00000000000..7b203884c4e
--- /dev/null
+++ b/src/plugins/fateshare/vpp_fateshare_monitor.c
@@ -0,0 +1,261 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/prctl.h> // prctl(), PR_SET_PDEATHSIG
+
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <limits.h>
+
+typedef struct
+{
+ pid_t pid;
+ char *cmd;
+} child_record_t;
+
+int n_children = 0;
+child_record_t *children = NULL;
+
+static void
+child_handler (int sig)
+{
+ pid_t pid;
+ int status;
+
+ while ((pid = waitpid (-1, &status, WNOHANG)) > 0)
+ {
+ int i;
+ printf ("fateshare: pid %d quit with status %d\n", pid, status);
+ for (i = 0; i < n_children; i++)
+ {
+ if (children[i].pid == pid)
+ {
+ children[i].pid = 0;
+ }
+ }
+ }
+}
+
+static void
+term_handler (int sig)
+{
+ int i;
+
+ printf ("fateshare: terminating!\n");
+ for (i = 0; i < n_children; i++)
+ {
+ kill (-children[i].pid, SIGTERM);
+ }
+ exit (0);
+}
+
+static void
+hup_handler (int sig)
+{
+ int i;
+
+ printf ("fateshare: terminating all the child processes!\n");
+ for (i = 0; i < n_children; i++)
+ {
+ kill (-children[i].pid, SIGTERM);
+ }
+}
+
+pid_t
+launch_command (char *scmd, char *logname_base)
+{
+ pid_t ppid_before_fork = getpid ();
+ pid_t cpid = fork ();
+ if (cpid == -1)
+ {
+ perror ("fork");
+ sleep (1);
+ return 0;
+ }
+ if (cpid)
+ {
+ /* parent */
+ return cpid;
+ }
+
+ /* child */
+ int r = prctl (PR_SET_PDEATHSIG, SIGTERM);
+ if (r == -1)
+ {
+ perror ("prctl");
+ sleep (5);
+ exit (1);
+ }
+ if (getppid () != ppid_before_fork)
+ {
+ sleep (5);
+ exit (1);
+ }
+
+ int r1 = setpgid (getpid (), 0);
+ if (r1 != 0)
+ {
+ perror ("setpgid error");
+ sleep (5);
+ exit (1);
+ }
+
+ int fd = open ("/dev/null", O_RDONLY);
+ if (fd < 0)
+ {
+ sleep (5);
+ exit (1);
+ }
+ while (fd >= 0)
+ {
+ close (fd);
+ fd--;
+ }
+ fd = open ("/dev/null", O_RDONLY);
+ if (fd < 0)
+ {
+ sleep (5);
+ exit (1);
+ }
+ dup2 (fd, 0);
+
+ char logname_stdout[PATH_MAX];
+ char logname_stderr[PATH_MAX];
+
+ snprintf (logname_stdout, PATH_MAX - 1, "%s-stdout.txt", logname_base);
+ snprintf (logname_stderr, PATH_MAX - 1, "%s-stderr.txt", logname_base);
+
+ printf ("LOG STDOUT %s: %s\n", scmd, logname_stdout);
+ printf ("LOG STDERR %s: %s\n", scmd, logname_stderr);
+
+ fd = open ((char *) logname_stdout, O_APPEND | O_RDWR | O_CREAT, 0777);
+ if (fd < 0)
+ {
+ sleep (5);
+ exit (1);
+ }
+ dup2 (fd, 1);
+ fd = open ((char *) logname_stderr, O_APPEND | O_RDWR | O_CREAT, 0777);
+ if (fd < 0)
+ {
+ sleep (5);
+ exit (1);
+ }
+ dup2 (fd, 2);
+
+ char *argv[] = { (char *) scmd, 0 };
+ int res = execv (argv[0], argv);
+ if (res != 0)
+ {
+ perror ("execve");
+ }
+ sleep (10);
+
+ exit (42);
+}
+
+int
+main (int argc, char **argv)
+{
+ pid_t ppid = getppid ();
+ int i = 0;
+ if (argc < 3)
+ {
+ printf ("usage: %s <parent_pid> <logfile-basename>\n", argv[0]);
+ exit (1);
+ }
+ char *errptr = 0;
+ pid_t parent_pid = strtoll (argv[1], &errptr, 10);
+ char *logname_base = argv[2];
+
+ printf ("DEBUG: pid %d starting for parent pid %d\n", getpid (), ppid);
+ printf ("DEBUG: parent pid: %d\n", parent_pid);
+ printf ("DEBUG: base log name: %s\n", logname_base);
+ if (*errptr)
+ {
+ printf ("%s is not a valid parent pid\n", errptr);
+ exit (2);
+ }
+
+ int r = prctl (PR_SET_PDEATHSIG, SIGTERM);
+ if (r == -1)
+ {
+ perror (0);
+ exit (1);
+ }
+
+ /* Establish handler. */
+ struct sigaction sa;
+ sigemptyset (&sa.sa_mask);
+ sa.sa_flags = 0;
+ sa.sa_handler = child_handler;
+
+ sigaction (SIGCHLD, &sa, NULL);
+
+ sigemptyset (&sa.sa_mask);
+ sa.sa_flags = 0;
+ sa.sa_handler = term_handler;
+
+ sigaction (SIGTERM, &sa, NULL);
+
+ sigemptyset (&sa.sa_mask);
+ sa.sa_flags = 0;
+ sa.sa_handler = hup_handler;
+
+ sigaction (SIGHUP, &sa, NULL);
+
+ if (getppid () != parent_pid)
+ {
+ printf ("parent process unexpectedly finished\n");
+ exit (3);
+ }
+
+ argc -= 3; /* skip over argv0, ppid, and log base */
+ argv += 3;
+
+ n_children = argc;
+ printf ("DEBUG: total %d children\n", n_children);
+ children = calloc (n_children, sizeof (children[0]));
+ for (i = 0; i < n_children; i++)
+ {
+ /* argv persists, so we can just use that pointer */
+ children[i].cmd = argv[i];
+ children[i].pid = launch_command (children[i].cmd, logname_base);
+ printf ("DEBUG: child %d (%s): initial launch pid %d\n", i,
+ children[i].cmd, children[i].pid);
+ }
+
+ while (1)
+ {
+ sleep (1);
+ pid_t curr_ppid = getppid ();
+ printf ("pid: %d, current ppid %d, original ppid %d\n", getpid (),
+ curr_ppid, ppid);
+ if (curr_ppid != ppid)
+ {
+ printf ("current ppid %d != original ppid %d - force quit\n",
+ curr_ppid, ppid);
+ fflush (stdout);
+ exit (1);
+ }
+ int restarted = 0;
+ for (i = 0; i < n_children; i++)
+ {
+ if (children[i].pid == 0)
+ {
+ printf ("child %s exited, restarting\n", children[i].cmd);
+ restarted = 1;
+ children[i].pid = launch_command (children[i].cmd, logname_base);
+ }
+ }
+ if (restarted)
+ {
+ sleep (1);
+ }
+
+ fflush (stdout);
+ }
+}