From 2eb89fa06207c7cd2380ba4efbf6754ceff9e415 Mon Sep 17 00:00:00 2001
From: abraunegg <alex.braunegg@gmail.com>
Date: Thu, 12 Feb 2026 07:47:18 +1100
Subject: [PATCH] Fix Bug #3637: Fix internal crash when WebSocket
 initialisation fails in monitor mode (#3639)

This PR fixes an internal crash in --monitor mode when WebSocket (Socket.IO) initialisation fails (for example, when Microsoft Graph returns 400 notSupported).

Previously, a failed WebSocket initialisation could leave the internal oneDriveSocketIo object unset (null), while later monitor-loop logic still assumed it was available. This resulted in a null dereference and a SIGSEGV, causing the client to exit after the first monitor loop.
---
 src/config.d |  7 ++++++-
 src/main.d   | 17 +++++++++++++----
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/config.d b/src/config.d
index ad004262..2efa911e 100644
--- a/src/config.d
+++ b/src/config.d
@@ -1784,11 +1784,16 @@ class ApplicationConfig {
 			addLogEntry();
 			addLogEntry("--------------------DEVELOPER_OPTIONS----------------------------");
 			addLogEntry("Config option 'force_children_scan'          = " ~ to!string(getValueBool("force_children_scan")));
-			addLogEntry();
+			addLogEntry("Config option 'monitor_max_loop'             = " ~ to!string(getValueLong("monitor_max_loop")));
+			addLogEntry("Config option 'display_memory'               = " ~ to!string(getValueBool("display_memory")));
+			addLogEntry("Config option 'display_sync_options'         = " ~ to!string(getValueBool("display_sync_options")));
+			addLogEntry("Config option 'display_processing_time'      = " ~ to!string(getValueBool("display_processing_time")));
 		}
 		
+		// Close out config output
 		if (getValueBool("display_running_config")) {
 			addLogEntry("-----------------------------------------------------------------");
+			addLogEntry();
 		}
 	}
 	
diff --git a/src/main.d b/src/main.d
index db47d015..93d03bb9 100644
--- a/src/main.d
+++ b/src/main.d
@@ -1033,6 +1033,8 @@ int main(string[] cliArgs) {
 								addLogEntry("Enabled WebSocket support to monitor Microsoft Graph API changes in near real-time.");
 							} else {
 								addLogEntry("ERROR: Unable to configure WebSocket support to monitor Microsoft Graph API changes in near real-time.");
+								if (debugLogging) {addLogEntry("Setting 'disable_websocket_support' to 'true' to force WebSockets to be disabled.", ["debug"]);}
+								appConfig.setValueBool("disable_websocket_support" , true);
 							}
 						} else {
 							// WebSocket Support has been disabled
@@ -1403,7 +1405,7 @@ int main(string[] cliArgs) {
 								Duration nextWebhookCheckDuration = oneDriveWebhook.getNextExpirationCheckDuration();
 								if (nextWebhookCheckDuration < sleepTime) sleepTime = nextWebhookCheckDuration;
 								notificationReceived = false;
-							} else if (!appConfig.getValueBool("disable_websocket_support") && appConfig.curlSupportsWebSockets) {
+							} else if (oneDriveSocketIo !is null && !appConfig.getValueBool("disable_websocket_support") && appConfig.curlSupportsWebSockets) {
 								Duration nextWebsocketCheckDuration = oneDriveSocketIo.getNextExpirationCheckDuration();
 								if (nextWebsocketCheckDuration < sleepTime) sleepTime = nextWebsocketCheckDuration;
 							}
@@ -1856,9 +1858,16 @@ extern(C) nothrow @nogc @system void exitViaSignalHandler(int signo) {
     if (signo == SIGSEGV) {
 		// Was SIGTERM used?
 		if (!sigtermHandlerTriggered) {
-			// No .. so most likely SIGINT (CTRL-C)
-			printf("Due to a termination signal, internal processing stopped abruptly. The application will now exit in a unclean manner.\n");
-			exit(130);
+			// No .. so most likely SIGINT (CTRL-C) - lets check
+			if (signo == SIGINT) {
+				// Yes - SIGINT was used
+				printf("Due to a termination signal, internal processing stopped abruptly. The application will now exit in a unclean manner.\n");
+				exit(130);
+			} else {
+				// Confirmed as SIGSEGV, but not SIGINT and SIGTERM not used
+				printf("FATAL: Segmentation fault (SIGSEGV). The application encountered an internal error and will now exit in a unclean manner.\n");
+				exit(139);
+			}
 		} else {
 			// High probability of being shutdown by systemd, for example: systemctl --user stop onedrive
 			// Exit in a manner that does not trigger an exit failure in systemd