From 23aced9775b503727e4b94f4b12fa1c9718cbf6d Mon Sep 17 00:00:00 2001
From: ~hatteb-mitlyd <anthony@tlon.io>
Date: Fri, 21 Mar 2014 18:08:58 -0700
Subject: [PATCH] Fork a child to handle checkpointing.

Kill the noise, and handle exit status from the child. If anything
untoward happens to the child, we need to know about it.
---
 Makefile |  2 +-
 v/save.c | 16 ++++++++--------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index a6785f10e..ff19fcd8a 100644
--- a/Makefile
+++ b/Makefile
@@ -54,7 +54,7 @@ LIBS=-lssl -lcrypto -lgmp -lncurses -lsigsegv $(OSLIBS)
 
 INCLUDE=include
 GENERATED=generated
-MDEFINES=-DU2_OS_$(OS) -DU2_OS_ENDIAN_$(ENDIAN) -D U2_LIB=\"$(LIB)\"
+MDEFINES=-DU2_OS_$(OS) -DU2_OS_ENDIAN_$(ENDIAN) -D U2_LIB=\"$(LIB)\" -DFORKPT
 
 CFLAGS=-O3 \
 	-I/usr/local/include \
diff --git a/v/save.c b/v/save.c
index 980fa1eb0..cf82a47d2 100644
--- a/v/save.c
+++ b/v/save.c
@@ -23,12 +23,8 @@
 static void
 _save_sign_cb(uv_signal_t* sil_u, c3_i num_i)
 {
-  uL(fprintf(uH, "save: signal %d\n", num_i));
-  {
-    switch ( num_i ) {
-      case SIGCHLD: u2_save_ef_chld(); break;
-    }
-  }
+  c3_assert(SIGCHLD == num_i);
+  u2_save_ef_chld();
 }
 
 /* _save_time_cb(): timer callback.
@@ -55,7 +51,7 @@ _save_time_cb(uv_timer_t* tim_u, c3_i sas_i)
       exit(0);
     }
     else {
-      uL(fprintf(uH, "checkpoint: process %d\n", pid_w));
+      //  uL(fprintf(uH, "checkpoint: process %d\n", pid_w));
 
       sav_u->ent_w = u2A->ent_w;
       sav_u->pid_w = pid_w;
@@ -78,13 +74,14 @@ u2_save_ef_chld(void)
 
   /* modified for cases with no pid_w
   */
-  uL(fprintf(uH, "checkpoint: complete %d\n", sav_u->pid_w));
+  //  uL(fprintf(uH, "checkpoint: complete %d\n", sav_u->pid_w));
   pid_w = wait(&loc_i);
   if (0 != sav_u->pid_w) {
     c3_assert(pid_w == sav_u->pid_w);
   }
   else {
     c3_assert(pid_w > 0);
+    c3_assert(WIFEXITED(pid_w) && 0 == WEXITSTATUS(pid_w));
   }
   sav_u->pid_w = 0;
 }
@@ -102,7 +99,10 @@ u2_save_io_init(void)
   uv_timer_init(u2L, &sav_u->tim_u);
   uv_timer_start(&sav_u->tim_u, _save_time_cb, 15000, 15000);
 
+#ifdef FORKPT
+  uv_signal_init(u2L, &sav_u->sil_u);
   uv_signal_start(&sav_u->sil_u, _save_sign_cb, SIGCHLD);
+#endif
 }
 
 /* u2_save_io_exit(): terminate save I/O.