s6

commit e2f01f98672c501b6ec4b445956b48041267138f
parent df194e5564f5b32aaf0e107b97095a1dd5bdbe35
Author: Laurent Bercot <ska-skaware@skarnet.org>
Date:   Wed, 17 Jun 2015 10:38:04 +0000

 - Add support for SIGUSR1 for poweroff in s6-svscan
 - Optimize respawn delay in s6-supervise

Diffstat:
M
doc/s6-svscan.html
 | 
3
++-
M
src/supervision/s6-supervise.c
 | 
15
+++++++++++----
M
src/supervision/s6-svscan.c
 | 
10
+++++++++-

3 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/doc/s6-svscan.html b/doc/s6-svscan.html
@@ -92,7 +92,8 @@ scan (and a reap) every 5 seconds. It is <em>strongly</em> discouraged to set
  <li> SIGHUP&nbsp;: acts as if a <tt>s6-svscanctl -h</tt> command had been received. </li>
  <li> SIGQUIT&nbsp;: acts as if a <tt>s6-svscanctl -q</tt> command had been received. </li>
  <li> SIGABRT&nbsp;: acts as if a <tt>s6-svscanctl -b</tt> command had been received. </li>
- <li> SIGINT&nbsp;: acts as if a <tt>s6-svscanctl -i</tt> command had been received. </li>
+ <li> SIGINT&nbsp;: acts as if a <tt>s6-svscanctl -6</tt> command had been received. </li>
+ <li> SIGUSR1&nbsp;: acts as if a <tt>s6-svscanctl -7</tt> command had been received. </li>
 </ul>
 
 <h2> The reaper </h2>
diff --git a/src/supervision/s6-supervise.c b/src/supervision/s6-supervise.c
@@ -44,11 +44,19 @@ typedef void action_t (void) ;
 typedef action_t *action_t_ref ;
 
 static tain_t deadline ;
+static tain_t dontrespawnbefore = TAIN_EPOCH ;
 static s6_svstatus_t status = { .stamp = TAIN_ZERO, .pid = 0, .flagwant = 1, .flagwantup = 1, .flagpaused = 0, .flagfinishing = 0, .wstat = 0 } ;
 static state_t state = DOWN ;
 static int cont = 1 ;
 static int notifyfd = -1 ;
 
+static inline void down_and_delay (void)
+{
+  state = DOWN ;
+  if (tain_future(&dontrespawnbefore)) deadline = dontrespawnbefore ;
+  else tain_copynow(&deadline) ;
+}
+
 static inline void settimeout (int secs)
 {
   tain_addsec_g(&deadline, secs) ;
@@ -247,6 +255,7 @@ static void trystart (void)
   state = UP ;
   status.pid = pid ;
   tain_copynow(&status.stamp) ;
+  tain_addsec_g(&dontrespawnbefore, 1) ;
   announce() ;
   ftrigw_notifyb_nosig(S6_SUPERVISE_EVENTDIR, "u", 1) ;
 }
@@ -291,8 +300,7 @@ static inline void tryfinish (int islast)
   {
     strerr_warnwu2sys("fork for ", "./finish") ;
     if (islast) bail() ;
-    state = DOWN ;
-    settimeout(1) ;
+    down_and_delay() ;
     return ;
   }
   else if (!pid)
@@ -385,9 +393,8 @@ static void finish_z (void)
 {
   status.pid = 0 ;
   status.flagfinishing = 0 ;
-  state = DOWN ;
+  down_and_delay() ;
   announce() ;
-  settimeout(1) ;
 }
 
 static void finish_u (void)
diff --git a/src/supervision/s6-svscan.c b/src/supervision/s6-svscan.c
@@ -109,6 +109,12 @@ static void intr (void)
   term() ;
 }
 
+static void usr1 (void)
+{
+  finish_arg = "poweroff" ;
+  term() ;
+}
+
 static void handle_signals (void)
 {
   for (;;)
@@ -124,6 +130,7 @@ static void handle_signals (void)
       case SIGQUIT : quit() ; break ;
       case SIGABRT : cont = 0 ; break ;
       case SIGINT : intr() ; break ;
+      case SIGUSR1 : usr1() ; break ;
     }
   }
 }
@@ -152,7 +159,7 @@ static void handle_control (int fd)
       case 'i' : intr() ; return ;
       case 'q' : quit() ; return ;
       case '0' : finish_arg = "halt" ; term() ; return ;
-      case '7' : finish_arg = "poweroff" ; term() ; return ;
+      case '7' : usr1() ; return ;
       case '8' : finish_arg = "other" ; term() ; return ;
       default :
       {
@@ -446,6 +453,7 @@ int main (int argc, char const *const *argv)
     sigaddset(&set, SIGQUIT) ;
     sigaddset(&set, SIGABRT) ;
     sigaddset(&set, SIGINT) ;
+    sigaddset(&set, SIGUSR1) ;
     if (selfpipe_trapset(&set) < 0) strerr_diefu1sys(111, "trap signals") ;
   }