pcp update: pmcd agent auto-restart

["Frank Ch. Eigler" <fche@xxxxxxxxxx>]

Hi -

Please see pcpfans.git fche/pmcd-autorestart for a patch of some dozen
lines that accomplishes pmda auto-restart entirely within pmcd.  No
pmie, no pmsignal, nothing else needed.


    RHBZ1323521: pmcd agent auto-restart
    
    A few lines of code in pmcd's ClientLoop allow it to connect the
    preexisting flags that detect recent agent malfunctions to the
    preexisting code to trigger agent restarts.  In this case, the
    automatic restarting is limited once per minute.

diff --git a/src/pmcd/src/pmcd.c b/src/pmcd/src/pmcd.c
index 511944ccfc92..dccb1f95491c 100644
--- a/src/pmcd/src/pmcd.c
+++ b/src/pmcd/src/pmcd.c
@@ -29,6 +29,7 @@ static char   *FdToString(int);
 static void    ResetBadHosts(void);
 
 int            AgentDied;              /* for updating mapdom[] */
+int            AgentPendingRestart;    /* for automatic restart */
 static int     timeToDie;              /* For SIGINT handling */
 static int     restart;                /* For SIGHUP restart */
 static int     maxReqPortFd;           /* Largest request port fd */
@@ -749,6 +750,19 @@ ClientLoop(void)
            __pmNotifyErr(LOG_ERR, "ClientLoop select: %s\n", netstrerror());
            break;
        }
+       if (AgentDied) {
+           AgentPendingRestart = 1;
+       }
+       if (AgentPendingRestart) {
+           static time_t last_restart;
+           time_t now = time(NULL);
+           if ((now - last_restart) >= 60) {
+               AgentPendingRestart = 0;
+               last_restart = now;
+               __pmNotifyErr(LOG_INFO, "Auto-restarting agents.\n");
+               restart = 1;
+           }
+       }
        if (restart) {
            restart = 0;
            reload_ns = 1;