From 5576de3f71170f61dc5955cac4f02258de460e98 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Majdand=C5=BEi=C4=87?= <dmajdandzic@neos.hr>
Date: Thu, 6 Apr 2023 20:14:47 +0200
Subject: [PATCH] Fix issue with application crashing on long sms without long
 sms processing enabled

---
 .../Preprocessor/Client/LongSmsProcessor.ts   | 36 +++++++++++--------
 src/SmppSession.ts                            | 10 ++++--
 2 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/src/PDUProcessor/Preprocessor/Client/LongSmsProcessor.ts b/src/PDUProcessor/Preprocessor/Client/LongSmsProcessor.ts
index de524ae..9cae1e7 100644
--- a/src/PDUProcessor/Preprocessor/Client/LongSmsProcessor.ts
+++ b/src/PDUProcessor/Preprocessor/Client/LongSmsProcessor.ts
@@ -6,6 +6,7 @@ const smpp = require('smpp');
 
 export default class LongSmsProcessor extends Preprocessor {
 	private iterator: number = 0;
+	static readonly maxMessageSizeBits = 1072;
 
 	constructor(type: string) {
 		// An sms can have a maximum length (short_message) of 1120 bits or 140 bytes.
@@ -31,25 +32,12 @@ export default class LongSmsProcessor extends Preprocessor {
 	processPdu(session: any, pdu: PDU, entity?: SmppSession | undefined): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
 			if (!!pdu.short_message) {
-				let encoding: number | undefined = pdu.data_coding;
-				if (!encoding) {
-					encoding = 0;
-				}
-				let characterSizeBits: number = 0;
-				switch (encoding) {
-					case 0:
-					case 1:
-						characterSizeBits = 8;
-						break;
-					case 8:
-						characterSizeBits = 16;
-						break;
-				}
+				let characterSizeBits: number = LongSmsProcessor.getCharacterSizeForEncoding(pdu);
+				let maxMessageLength: number = LongSmsProcessor.maxMessageSizeBits / characterSizeBits;
 				if (characterSizeBits) {
 					let splitMessage: string[] = [];
 					let message: string = pdu.short_message;
 					let messageLength: number = message.length;
-					let maxMessageLength: number = 1072 / characterSizeBits;
 					let messageCount: number = Math.ceil(messageLength / maxMessageLength);
 					for (let i = 0; i < messageCount; i++) {
 						splitMessage.push(message.substr(i * maxMessageLength, maxMessageLength));
@@ -77,4 +65,22 @@ export default class LongSmsProcessor extends Preprocessor {
 			}
 		});
 	}
+
+	static getCharacterSizeForEncoding(pdu: PDU) {
+		let encoding: number | undefined = pdu.data_coding;
+		if (!encoding) {
+			encoding = 0;
+		}
+		let characterSizeBits: number = 0;
+		switch (encoding) {
+			case 0:
+			case 1:
+				characterSizeBits = 8;
+				break;
+			case 8:
+				characterSizeBits = 16;
+				break;
+		}
+		return characterSizeBits;
+	}
 }
\ No newline at end of file
diff --git a/src/SmppSession.ts b/src/SmppSession.ts
index 296faa7..d8fc9ef 100644
--- a/src/SmppSession.ts
+++ b/src/SmppSession.ts
@@ -4,6 +4,7 @@ import Job from "./Job/Job";
 import Logger from "./Logger";
 import PduProcessor from "./PDUProcessor/PduProcessor";
 import Postprocessor from "./PDUProcessor/Postprocessor/Postprocessor";
+import LongSmsProcessor from "./PDUProcessor/Preprocessor/Client/LongSmsProcessor";
 import Preprocessor from "./PDUProcessor/Preprocessor/Preprocessor";
 
 const NanoTimer = require("nanotimer");
@@ -114,9 +115,14 @@ export default abstract class SmppSession {
 
 	doSendPdu(pdu: PDU, session: any): Promise<any> {
 		return new Promise<any>((resolve, reject) => {
-			this.eventEmitter.emit(this.EVENT.ANY_PDU_TX, pdu);
+			let characterSizeBits: number = LongSmsProcessor.getCharacterSizeForEncoding(pdu);
+			let maxMessageLength: number = LongSmsProcessor.maxMessageSizeBits / characterSizeBits;
+			if (!!pdu.short_message && pdu.short_message.length > maxMessageLength) {
+				pdu.short_message = pdu.short_message.substring(0, maxMessageLength);
+			}
 			session.send(pdu, (reply: any) => resolve(reply));
-		})
+			this.eventEmitter.emit(this.EVENT.ANY_PDU_TX, pdu);
+		});
 	}
 
 	sendSingle(job: Job): Promise<object> {