diff options
Diffstat (limited to 'src/plugins/fateshare/vpp_fateshare_monitor.c')
| -rw-r--r-- | src/plugins/fateshare/vpp_fateshare_monitor.c | 261 |
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); + } +} |