From 8efbc4bc329b4063f26132760e81a784580963f7 Mon Sep 17 00:00:00 2001
From: Shivaram Lingamneni <slingamn@cs.stanford.edu>
Date: Thu, 14 May 2020 22:16:34 -0400
Subject: [PATCH] maintain lenBytes as a running count

---
 irc/client.go     |  3 ++-
 irc/handlers.go   |  6 +++++-
 irc/utils/text.go | 14 --------------
 3 files changed, 7 insertions(+), 16 deletions(-)

diff --git a/irc/client.go b/irc/client.go
index a5cc0f8f..b5204b3d 100644
--- a/irc/client.go
+++ b/irc/client.go
@@ -146,6 +146,7 @@ type MultilineBatch struct {
 	target        string
 	responseLabel string // this is the value of the labeled-response tag sent with BATCH
 	message       utils.SplitMessage
+	lenBytes      int
 	tags          map[string]string
 }
 
@@ -168,7 +169,7 @@ func (s *Session) EndMultilineBatch(label string) (batch MultilineBatch, err err
 	s.fakelag.Unsuspend()
 
 	// heuristics to estimate how much data they used while fakelag was suspended
-	fakelagBill := (batch.message.LenBytes() / 512) + 1
+	fakelagBill := (batch.lenBytes / 512) + 1
 	fakelagBillLines := (batch.message.LenLines() * 60) / 512
 	if fakelagBill < fakelagBillLines {
 		fakelagBill = fakelagBillLines
diff --git a/irc/handlers.go b/irc/handlers.go
index c6745d95..467881e8 100644
--- a/irc/handlers.go
+++ b/irc/handlers.go
@@ -1816,9 +1816,13 @@ func absorbBatchedMessage(server *Server, client *Client, msg ircmsg.IrcMessage,
 		errorCode, errorMessage = "MULTILINE_INVALID", client.t("Cannot send a blank line with the multiline concat tag")
 		return
 	}
+	if !isConcat && len(rb.session.batch.message.Split) != 0 {
+		rb.session.batch.lenBytes++ // bill for the newline
+	}
 	rb.session.batch.message.Append(msg.Params[1], isConcat)
+	rb.session.batch.lenBytes += len(msg.Params[1])
 	config := server.Config()
-	if config.Limits.Multiline.MaxBytes < rb.session.batch.message.LenBytes() {
+	if config.Limits.Multiline.MaxBytes < rb.session.batch.lenBytes {
 		errorCode, errorMessage = "MULTILINE_MAX_BYTES", strconv.Itoa(config.Limits.Multiline.MaxBytes)
 	} else if config.Limits.Multiline.MaxLines != 0 && config.Limits.Multiline.MaxLines < rb.session.batch.message.LenLines() {
 		errorCode, errorMessage = "MULTILINE_MAX_LINES", strconv.Itoa(config.Limits.Multiline.MaxLines)
diff --git a/irc/utils/text.go b/irc/utils/text.go
index d77b88d4..62c49eb5 100644
--- a/irc/utils/text.go
+++ b/irc/utils/text.go
@@ -67,20 +67,6 @@ func (sm *SplitMessage) LenLines() int {
 	return len(sm.Split)
 }
 
-func (sm *SplitMessage) LenBytes() (result int) {
-	if sm.Split == nil {
-		return len(sm.Message)
-	}
-	for i := 0; i < len(sm.Split); i++ {
-		result += len(sm.Split[i].Message)
-		// bill for the joining newline if necessary
-		if i != 0 && !sm.Split[i].Concat {
-			result += 1
-		}
-	}
-	return
-}
-
 func (sm *SplitMessage) ValidMultiline() bool {
 	// must contain at least one nonblank line
 	for i := 0; i < len(sm.Split); i++ {