From 1344b730aff4953364ed5fb4f76dff1414b68c37 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jose=20Luis=20Monta=C3=B1es=20Ojados?= <joseluis@zubi.group>
Date: Mon, 19 Jan 2026 16:17:28 +0100
Subject: [PATCH] fix: Increase scanner buffer size to 5MB and add error
 logging to prevent silent capture failures

---
 internal/capture/capturer.go | 11 +++++++++++
 internal/capture/local.go    | 12 ++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/internal/capture/capturer.go b/internal/capture/capturer.go
index efa52d4..8efa0c5 100644
--- a/internal/capture/capturer.go
+++ b/internal/capture/capturer.go
@@ -103,6 +103,11 @@ func (c *Capturer) IsRunning() bool {
 
 func (c *Capturer) processStream(r io.Reader) {
 	scanner := bufio.NewScanner(r)
+	// Increase buffer size to handle large packets
+	const maxCapacity = 5 * 1024 * 1024 // 5MB
+	buf := make([]byte, 0, 64*1024)
+	scanner.Buffer(buf, maxCapacity)
+
 	var buffer strings.Builder
 	inSIPMessage := false
 	var msgNetInfo *NetInfo
@@ -159,6 +164,12 @@ func (c *Capturer) processStream(r io.Reader) {
 	if buffer.Len() > 0 {
 		c.parseAndEmit(buffer.String(), msgNetInfo)
 	}
+
+	if err := scanner.Err(); err != nil {
+		if c.OnError != nil {
+			c.OnError(fmt.Errorf("scanner error: %w", err))
+		}
+	}
 }
 
 func (c *Capturer) processErrors(r io.Reader) {
diff --git a/internal/capture/local.go b/internal/capture/local.go
index cf1671a..fdcc90c 100644
--- a/internal/capture/local.go
+++ b/internal/capture/local.go
@@ -125,6 +125,11 @@ func (c *LocalCapturer) Close() error {
 
 func (c *LocalCapturer) processStream(r io.Reader) {
 	scanner := bufio.NewScanner(r)
+	// Increase buffer size to handle large packets (default is 64KB)
+	const maxCapacity = 5 * 1024 * 1024 // 5MB
+	buf := make([]byte, 0, 64*1024)
+	scanner.Buffer(buf, maxCapacity)
+
 	var buffer strings.Builder
 	inSIPMessage := false
 	var msgNetInfo *NetInfo
@@ -199,6 +204,13 @@ func (c *LocalCapturer) processStream(r io.Reader) {
 	if buffer.Len() > 0 {
 		c.parseAndEmit(buffer.String(), msgNetInfo)
 	}
+
+	if err := scanner.Err(); err != nil {
+		logger.Error("Scanner error: %v", err)
+		if c.OnError != nil {
+			c.OnError(fmt.Errorf("scanner error: %w", err))
+		}
+	}
 }
 
 func (c *LocalCapturer) processErrors(r io.Reader) {