From 17cbe2ceb2b814447c325af2de3df056bc251842 Mon Sep 17 00:00:00 2001
From: Graham Clark <grclark@gmail.com>
Date: Sun, 7 Feb 2021 15:19:08 -0500
Subject: [PATCH] A function to allow the current source to be reloaded
 directly

I haven't had an API until now because I haven't needed to reload unless
some information has changed - such as the display filter or the pcap
source. However soon the displayed columns will be configurable, so I
want to be able to redisplay. An alternative would be for termshark,
when loading the PSML, to request *every* column; save those internally,
and then just display the columns the user wants to see. I decided
against this because it would use a good deal more memory on larger
pcaps, and I don't imagine changing columns is an operation that is done
on every pcap load. So instead of making every termshark instance pay
the price by loading every column value, I just reload the pcap when the
columns change.
---
 pcap/loader.go | 40 ++++++++++++++++------------------------
 ui/ui.go       | 24 +++++++++++++++++++++++-
 2 files changed, 39 insertions(+), 25 deletions(-)

diff --git a/pcap/loader.go b/pcap/loader.go
index 4bc8366..a2ae882 100644
--- a/pcap/loader.go
+++ b/pcap/loader.go
@@ -427,35 +427,27 @@ func (c *ParentLoader) StopLoadPsmlAndIface(cb interface{}) {
 
 //======================================================================
 
-// NewFilter is essentially a completely new load - psml + pdml. But not iface, if that's running
-func (c *PacketLoader) NewFilter(newfilt string, cb interface{}, app gowid.IApp) {
-
-	log.Infof("Requested application of display filter '%v'", newfilt)
-
-	if c.DisplayFilter() == newfilt {
-		log.Infof("No operation - same filter applied ('%s').", newfilt)
-	} else {
-		c.stopTail()
-		c.stopLoadPsml()
-		c.stopLoadPdml()
+func (c *PacketLoader) Reload(filter string, cb interface{}, app gowid.IApp) {
+	c.stopTail()
+	c.stopLoadPsml()
+	c.stopLoadPdml()
 
-		OpsChan <- gowid.RunFunction(func(app gowid.IApp) {
-			c.RenewPsmlLoader()
-			c.RenewPdmlLoader()
+	OpsChan <- gowid.RunFunction(func(app gowid.IApp) {
+		c.RenewPsmlLoader()
+		c.RenewPdmlLoader()
 
-			// This is not ideal. I'm clearing the views, but I'm about to
-			// restart. It's not really a new source, so called the new source
-			// handler is an untify way of updating the current capture in the
-			// title bar again
-			handleClear(NoneCode, app, cb)
+		// This is not ideal. I'm clearing the views, but I'm about to
+		// restart. It's not really a new source, so called the new source
+		// handler is an untify way of updating the current capture in the
+		// title bar again
+		handleClear(NoneCode, app, cb)
 
-			c.displayFilter = newfilt
+		c.displayFilter = filter
 
-			log.Infof("Applying new display filter '%s'", newfilt)
+		log.Infof("Applying display filter '%s'", filter)
 
-			c.loadPsmlSync(c.InterfaceLoader, c, cb, app)
-		})
-	}
+		c.loadPsmlSync(c.InterfaceLoader, c, cb, app)
+	})
 }
 
 func (c *PacketLoader) LoadPcap(pcap string, displayFilter string, cb interface{}, app gowid.IApp) {
diff --git a/ui/ui.go b/ui/ui.go
index 23ab9f7..4d0e391 100644
--- a/ui/ui.go
+++ b/ui/ui.go
@@ -2410,7 +2410,29 @@ func RequestNewFilter(displayFilter string, app gowid.IApp) {
 		//MakeCancelledMessage(),
 	}
 
-	Loader.NewFilter(displayFilter, handlers, app)
+	if Loader.DisplayFilter() == displayFilter {
+		log.Infof("No operation - same filter applied ('%s').", displayFilter)
+	} else {
+		Loader.Reload(displayFilter, handlers, app)
+	}
+}
+
+func RequestReload(app gowid.IApp) {
+	handlers := pcap.HandlerList{
+		SimpleErrors{},
+		MakePacketViewUpdater(),
+		MakeUpdateCurrentCaptureInTitle(),
+		SetStructWidgets{Loader}, // for OnClear
+		ClearMarksHandler{},
+		// Don't use this one - we keep the cancelled flag set so that we
+		// don't restart live captures on clear if ctrl-c has been issued
+		// so we don't want this handler on a new filter because we don't
+		// want to be told again after applying the filter that the load
+		// was cancelled
+		//MakeCancelledMessage(),
+	}
+
+	Loader.Reload(Loader.DisplayFilter(), handlers, app)
 }
 
 //======================================================================