From a841dacf458636483cb0a12ab4e675ca0b862c2d Mon Sep 17 00:00:00 2001
From: kroening <kroening@6afb6bc1-c8e4-404c-8f48-9ae832c5b171>
Date: Wed, 4 Jan 2012 20:48:08 +0000
Subject: [PATCH 1/2] Release 4.1

git-svn-id: svn+ssh://svn.cprover.org/srv/svn/cbmc/releases/cbmc-4.1@861 6afb6bc1-c8e4-404c-8f48-9ae832c5b171

From 340e95869884577d6779eb4df4f7cf2bb4245591 Mon Sep 17 00:00:00 2001
From: Michael Tautschnig <mt@debian.org>
Date: Thu, 16 Jun 2011 01:31:03 +0100
Subject: [PATCH 2/2] bug#105: Proper signal handling and process group killing

- Only patched in CBMC, others have lost all signal handling
---
 src/cbmc/main.cpp           | 37 +++++++++++++++++++++++++++++++++++++
 src/util/parseoptions.cpp   |  4 ----
 src/util/signal_catcher.cpp | 11 +++++++++--
 src/util/signal_catcher.h   |  1 +
 4 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/src/cbmc/main.cpp b/src/cbmc/main.cpp
index 233cd8efcf3..1b848415151 100644
--- a/src/cbmc/main.cpp
+++ b/src/cbmc/main.cpp
@@ -15,6 +15,10 @@ Author: Daniel Kroening, kroening@kroening.com
 */
 
 #include "parseoptions.h"
+#include <signal_catcher.h> 
+
+#include <cstring>
+#include <sys/wait.h>
 
 /*******************************************************************\
 
@@ -30,6 +34,39 @@ Function: main
 
 int main(int argc, const char **argv)
 {
+#if defined(_WIN32)
   cbmc_parseoptionst parseoptions(argc, argv);
   return parseoptions.main();
+#else
+  if((argc>1 && 0==strcmp(argv[1],"+nofork"))
+      /* consider: || getpid() == getpgrp() 
+       * - no signal catcher in this case */)
+  {
+    argv[1]=argv[0];
+    cbmc_parseoptionst parseoptions(argc-1, argv+1);
+    return parseoptions.main();
+  }
+
+  pid_t child=fork();
+  assert(0<=child);
+  child_pgid=child;
+  if(0==child)
+  {
+    setpgid(0, getpid());
+    char ** args=new char*[argc+2];
+    args[0]=strdup(argv[0]);
+    args[1]=strdup("+nofork");
+    args[argc+1]=0;
+    while(--argc>0)
+      args[argc+1]=strdup(argv[argc]);
+    execvp(argv[0], args);
+    perror("Failed to run child");
+    assert(0);
+  }
+
+  install_signal_catcher();
+  int exitcode=-1;
+  waitpid(child, &exitcode, 0);
+  return WEXITSTATUS(exitcode);
+#endif
 }
diff --git a/src/util/parseoptions.cpp b/src/util/parseoptions.cpp
index e29fa559b8b..d1a01424f72 100644
--- a/src/util/parseoptions.cpp
+++ b/src/util/parseoptions.cpp
@@ -17,7 +17,6 @@ Author: Daniel Kroening, kroening@kroening.com
 
 #include "cmdline.h"
 #include "parseoptions.h"
-#include "signal_catcher.h"
 
 /*******************************************************************\
 
@@ -97,9 +96,6 @@ int parseoptions_baset::main()
     help();
     return EX_OK;
   }
-  
-  // install signal catcher
-  install_signal_catcher();
 
   return doit();
 }
diff --git a/src/util/signal_catcher.cpp b/src/util/signal_catcher.cpp
index 0808cd81ed7..1a214f38c8e 100644
--- a/src/util/signal_catcher.cpp
+++ b/src/util/signal_catcher.cpp
@@ -19,6 +19,8 @@
 
 #include "signal_catcher.h"
 
+pid_t child_pgid;
+
 /*******************************************************************\
 
 Function: install_signal_catcher
@@ -40,10 +42,15 @@ void install_signal_catcher()
 	
   act.sa_handler=signal_catcher;
   act.sa_flags=0;
-  sigfillset(&(act.sa_mask));
+  sigemptyset(&(act.sa_mask));
 
   // install signal handler
+  sigaction(SIGHUP, &act, NULL);
+  sigaction(SIGINT, &act, NULL);
   sigaction(SIGTERM, &act, NULL);
+  sigaction(SIGALRM, &act, NULL);
+  sigaction(SIGUSR1, &act, NULL);
+  sigaction(SIGUSR2, &act, NULL);
   #endif
 }
 
@@ -64,7 +71,7 @@ void signal_catcher(int sig)
   #if defined(_WIN32)
   #else
   // kill any children by killing group
-  killpg(0, sig);
+  killpg(child_pgid, sig);
 
   exit(sig);
   #endif
diff --git a/src/util/signal_catcher.h b/src/util/signal_catcher.h
index 9057730ed76..49e803c35d1 100644
--- a/src/util/signal_catcher.h
+++ b/src/util/signal_catcher.h
@@ -1,2 +1,3 @@
 void install_signal_catcher();
 void signal_catcher(int sig);
+extern pid_t child_pgid;