From c51128f051128567559a331d9f457d82518e036d Mon Sep 17 00:00:00 2001
From: Szekely Gyorgy <hoditohod@gmail.com>
Date: Mon, 22 Nov 2021 16:39:53 +0100
Subject: [PATCH] Unblock faulting thread signal handler after log flush is
 complete (#419)

---
 src/crashhandler_unix.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/crashhandler_unix.cpp b/src/crashhandler_unix.cpp
index a14985e..ea2f073 100644
--- a/src/crashhandler_unix.cpp
+++ b/src/crashhandler_unix.cpp
@@ -39,6 +39,8 @@
 
 namespace {
 
+   std::atomic<bool> gBlockForFatal {true};
+
    const std::map<int, std::string> kSignals = {
       {SIGABRT, "SIGABRT"},
       {SIGFPE, "SIGFPE"},
@@ -134,10 +136,9 @@ namespace g3 {
    namespace internal {
 
       bool shouldBlockForFatalHandling() {
-         return true;  // For windows we will after fatal processing change it to false
+         return gBlockForFatal;
       }
 
-
       /// Generate stackdump. Or in case a stackdump was pre-generated and non-empty just use that one
       /// i.e. the latter case is only for Windows and test purposes
       std::string stackdump(const char* rawdump) {
@@ -230,6 +231,12 @@ namespace g3 {
 
 
          kill(getpid(), signal_number);
+
+         // When running as PID1 the above kill doesn't have any effect (execution simply passes through it, contrary
+         // to a non-PID1 process where execution stops at kill and switches over to signal handling). Also as PID1 
+         // we must unblock the thread that received the original signal otherwise the process will never terminate.
+         gBlockForFatal = false;
+
          exit(signal_number);
 
       }