From ad870231cbb8d000dddbb20f49b3670bfbc9c4cd Mon Sep 17 00:00:00 2001
From: furszy <matiasfurszyfer@protonmail.com>
Date: Sun, 29 Sep 2019 12:44:32 -0300
Subject: [PATCH] [Startup][Refactor][Backport]

* OS memory allocation fail handler.
* OS signal handler registration method created to remove code duplication.
* AppInitBasicSetup() method created, organizing better the setup step of the wallet initialization.
---
 src/init.cpp | 64 ++++++++++++++++++++++++++++++++++++----------------
 src/init.h   |  6 +++++
 2 files changed, 51 insertions(+), 19 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index ff65039996895..00a57a0133846 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -307,7 +307,7 @@ void Shutdown()
  */
 void HandleSIGTERM(int)
 {
-    fRequestShutdown = true;
+    StartShutdown();
 }
 
 void HandleSIGHUP(int)
@@ -315,6 +315,17 @@ void HandleSIGHUP(int)
     fReopenDebugLog = true;
 }
 
+#ifndef WIN32
+static void registerSignalHandler(int signal, void(*handler)(int))
+{
+    struct sigaction sa;
+    sa.sa_handler = handler;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    sigaction(signal, &sa, nullptr);
+}
+#endif
+
 bool static InitError(const std::string& str)
 {
     uiInterface.ThreadSafeMessageBox(str, "", CClientUIInterface::MSG_ERROR);
@@ -748,10 +759,20 @@ bool AppInitServers()
     return true;
 }
 
-/** Initialize pivx.
- *  @pre Parameters should be parsed and config file should be read.
- */
-bool AppInit2()
+[[noreturn]] static void new_handler_terminate()
+{
+    // Rather than throwing std::bad-alloc if allocation fails, terminate
+    // immediately to (try to) avoid chain corruption.
+    // Since LogPrintf may itself allocate memory, set the handler directly
+    // to terminate first.
+    std::set_new_handler(std::terminate);
+    LogPrintf("Error: Out of memory. Terminating.\n");
+
+    // The log was successful, terminate now.
+    std::terminate();
+};
+
+bool AppInitBasicSetup()
 {
 // ********************************************************* Step 1: setup
 #ifdef _MSC_VER
@@ -764,7 +785,7 @@ bool AppInit2()
     _set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
 #endif
 #ifdef WIN32
-// Enable Data Execution Prevention (DEP)
+    // Enable Data Execution Prevention (DEP)
 // Minimum supported OS versions: WinXP SP3, WinVista >= SP1, Win Server 2008
 // A failure is non-critical and needs no further attention!
 #ifndef PROCESS_DEP_ENABLE
@@ -790,26 +811,31 @@ bool AppInit2()
         umask(077);
     }
 
-
-    // Clean shutdown on SIGTERM
-    struct sigaction sa;
-    sa.sa_handler = HandleSIGTERM;
-    sigemptyset(&sa.sa_mask);
-    sa.sa_flags = 0;
-    sigaction(SIGTERM, &sa, NULL);
-    sigaction(SIGINT, &sa, NULL);
+    // Clean shutdown on SIGTERMx
+    registerSignalHandler(SIGTERM, HandleSIGTERM);
+    registerSignalHandler(SIGINT, HandleSIGTERM);
 
     // Reopen debug.log on SIGHUP
-    struct sigaction sa_hup;
-    sa_hup.sa_handler = HandleSIGHUP;
-    sigemptyset(&sa_hup.sa_mask);
-    sa_hup.sa_flags = 0;
-    sigaction(SIGHUP, &sa_hup, NULL);
+    registerSignalHandler(SIGHUP, HandleSIGHUP);
 
     // Ignore SIGPIPE, otherwise it will bring the daemon down if the client closes unexpectedly
     signal(SIGPIPE, SIG_IGN);
 #endif
 
+    std::set_new_handler(new_handler_terminate);
+
+    return true;
+}
+
+/** Initialize pivx.
+ *  @pre Parameters should be parsed and config file should be read.
+ */
+bool AppInit2()
+{
+    // ********************************************************* Step 1: setup
+    if (!AppInitBasicSetup())
+        return false;
+
     // ********************************************************* Step 2: parameter interactions
     // Set this early so that parameter interactions go to console
     fPrintToConsole = GetBoolArg("-printtoconsole", false);
diff --git a/src/init.h b/src/init.h
index 17aab3ef62b39..c2f0644d06646 100644
--- a/src/init.h
+++ b/src/init.h
@@ -29,6 +29,12 @@ void Shutdown();
 void PrepareShutdown();
 bool AppInit2();
 
+/** Initialize PIVX core: Basic context setup.
+ *  @note This can be done before daemonization. Do not call Shutdown() if this function fails.
+ *  @pre Parameters should be parsed and config file should be read.
+ */
+bool AppInitBasicSetup();
+
 /** The help message mode determines what help message to show */
 enum HelpMessageMode {
     HMM_BITCOIND,