When receiving a SIGTERM wait() for children

cop/TrafficCop.cc

@@ -29,7 +29,6 @@
 
 #if defined(linux) || defined (solaris)
 #include "sys/utsname.h"
-#include "ink_killall.h"
 #include <sys/types.h>
 #include <sys/ipc.h>
 #include <sys/sem.h>
@@ -45,7 +44,7 @@ union semun
 #endif  // linux check
 
 // For debugging, turn this on.
-// #define TRACE_LOG_COP 1
+#define TRACE_LOG_COP 1
 
 #define OPTIONS_MAX     32
 #define OPTIONS_LEN_MAX 1024
@@ -212,6 +211,7 @@ chown_file_to_admin_user(const char *file) {
     }
   }
 }
+
 static void
 sig_child(int signum)
 {
@@ -238,6 +238,43 @@ sig_child(int signum)
   cop_log_trace("Leaving sig_child(%d)\n", signum);
 }
 
+static void
+sig_term(int signum)
+{
+  pid_t pid = 0;
+  int status = 0;
+  int err;
+  pid_t holding_pid;
+
+  //killsig = SIGTERM;
+
+  cop_log_trace("Entering sig_term(%d)\n", signum);
+
+  // safely^W commit suicide.
+  cop_log_trace("Sending signal %d to entire group\n", signum);
+  killpg(0, signum);
+
+  cop_log_trace("Waiting for children to exit.");
+
+  for (;;) {
+    pid = waitpid(WAIT_ANY, &status, WNOHANG);
+
+    if (pid <= 0) {
+      break;
+    }
+    // TSqa03086 - We can not log the child status signal from
+    //   the signal handler since syslog can deadlock.  Record
+    //   the pid and the status in a global for logging
+    //   next time through the event loop.  We will occasionally
+    //   lose some information if we get two sig childs in rapid
+    //   succession
+    child_pid = pid;
+    child_status = status;
+  }
+  cop_log_trace("Leaving sig_term(%d), exiting traffic_cop\n", signum);
+  exit(0);
+}
+
 static void
 #if defined(solaris)
 sig_fatal(int signum, siginfo_t * t, void *c)
@@ -1381,18 +1418,7 @@ check_programs()
   Lockfile manager_lf(manager_lockfile);
   err = manager_lf.Open(&holding_pid);
   chown_file_to_admin_user(manager_lockfile);
-#if defined(linux)
-  // if lockfile held, but process doesn't exist, killall and try again
-  if (err == 0) {
-    if (kill(holding_pid, 0) == -1) {
-      cop_log(COP_WARNING, "%s's lockfile is held, but its pid (%d) is missing;"
-              " killing all processes named '%s' and retrying\n", manager_binary, holding_pid, manager_binary);
-      ink_killall(manager_binary, killsig);
-      sleep(1);                 // give signals a chance to be received
-      err = manager_lf.Open(&holding_pid);
-    }
-  }
-#endif
+
   if (err > 0) {
     // 'lockfile_open' returns the file descriptor of the opened
     // lockfile.  We need to close this before spawning the
@@ -1473,18 +1499,7 @@ check_programs()
 
     Lockfile server_lf(server_lockfile);
     err = server_lf.Open(&holding_pid);
-#if defined(linux)
-    // if lockfile held, but process doesn't exist, killall and try again
-    if (err == 0) {
-      if (kill(holding_pid, 0) == -1) {
-        cop_log(COP_WARNING, "%s's lockfile is held, but its pid (%d) is missing;"
-                " killing all processes named '%s' and retrying\n", server_binary, holding_pid, server_binary);
-        ink_killall(server_binary, killsig);
-        sleep(1);               // give signals a chance to be received
-        err = server_lf.Open(&holding_pid);
-      }
-    }
-#endif
+
     if (err > 0) {
       server_lf.Close();
 
@@ -1673,6 +1688,15 @@ init_signals()
   struct sigaction action;
 
   cop_log_trace("Entering init_signals()\n");
+  // Handle the SIGTERM and SIGINT signal:
+  // We kill the process group and wait() for all children
+  action.sa_handler = sig_term;
+  sigemptyset(&action.sa_mask);
+  action.sa_flags = 0;
+
+  sigaction(SIGTERM, &action, NULL);
+  sigaction(SIGINT, &action, NULL);
+
   // Handle the SIGCHLD signal. We simply reap all children that
   // die (which should only be spawned traffic_manager's).
   action.sa_handler = sig_child;

lib/ts/Makefile.am

@@ -71,8 +71,6 @@ libtsutil_la_SOURCES = \
   ink_inet.cc \
   ink_inet.h \
   ink_inout.h \
-  ink_killall.cc \
-  ink_killall.h \
   ink_llqueue.h \
   ink_lockfile.h \
   INK_MD5.h \

lib/ts/libts.h

@@ -60,7 +60,6 @@
 #include "ink_hash_table.h"
 #include "ink_hrtime.h"
 #include "ink_inout.h"
-#include "ink_killall.h"
 #include "ink_llqueue.h"
 #include "ink_lockfile.h"
 #include "ink_memory.h"