From df427b6822c843a233ec0cad48624d2b1de87843 Mon Sep 17 00:00:00 2001
From: Andrey Meshkov <am@adguard.com>
Date: Fri, 21 Feb 2020 16:50:20 +0300
Subject: [PATCH] *(dnsforward): fix reading in-memory entries

---
 querylog/qlog.go          | 9 ++++++---
 querylog/qlog_file.go     | 6 +++++-
 querylog/querylog_file.go | 3 ---
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/querylog/qlog.go b/querylog/qlog.go
index fb49fa35..a0570011 100644
--- a/querylog/qlog.go
+++ b/querylog/qlog.go
@@ -208,14 +208,17 @@ func (l *queryLog) getData(params getDataParams) map[string]interface{} {
 	memoryEntries := make([]*logEntry, 0)
 
 	// go through the buffer in the reverse order
+	// from NEWER to OLDER
 	for i := len(l.buffer) - 1; i >= 0; i-- {
 		entry := l.buffer[i]
-		if !matchesGetDataParams(entry, params) {
+
+		if entry.Time.UnixNano() >= params.OlderThan.UnixNano() {
+			// Ignore entries newer than what was requested
 			continue
 		}
 
-		if entry.Time.UnixNano() >= params.OlderThan.UnixNano() {
-			break
+		if !matchesGetDataParams(entry, params) {
+			continue
 		}
 
 		memoryEntries = append(memoryEntries, entry)
diff --git a/querylog/qlog_file.go b/querylog/qlog_file.go
index 54d1896c..c1eeefa2 100644
--- a/querylog/qlog_file.go
+++ b/querylog/qlog_file.go
@@ -15,7 +15,11 @@ import (
 // if we failed to find the desired record
 var ErrSeekNotFound = errors.New("Seek not found the record")
 
-const bufferSize = 256 * 1024 // 256 KB is the buffer size
+// TODO: Find a way to grow buffer instead of relying on this value when reading strings
+const maxEntrySize = 16 * 1024
+
+// buffer should be enough for at least this number of entries
+const bufferSize = 100 * maxEntrySize
 
 // QLogFile represents a single query log file
 // It allows reading from the file in the reverse order
diff --git a/querylog/querylog_file.go b/querylog/querylog_file.go
index 3b32b7a2..1eeeea7c 100644
--- a/querylog/querylog_file.go
+++ b/querylog/querylog_file.go
@@ -9,9 +9,6 @@ import (
 	"github.com/AdguardTeam/golibs/log"
 )
 
-// TODO: Check this when we append a new line -- we don't want to have a line longer than this
-const maxEntrySize = 1024
-
 // flushLogBuffer flushes the current buffer to file and resets the current buffer
 func (l *queryLog) flushLogBuffer(fullFlush bool) error {
 	l.fileFlushLock.Lock()