From 1f1e26f67b00ee4983c65e4e3aabf59a488f687b Mon Sep 17 00:00:00 2001
From: Simon Zolin <s.zolin@adguard.com>
Date: Wed, 27 Mar 2019 17:09:48 +0300
Subject: [PATCH] + config: add "rlimit_nofile" setting - Maximum number of
 opened fd's per process

---
 app.go    | 17 +++++++++++++++++
 config.go | 12 +++++++-----
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/app.go b/app.go
index ba8aee3c..8484b553 100644
--- a/app.go
+++ b/app.go
@@ -92,6 +92,11 @@ func run(args options) {
 		log.Fatal(err)
 	}
 
+	if (runtime.GOOS == "linux" || runtime.GOOS == "darwin") &&
+		config.RlimitNoFile != 0 {
+		setRlimit(config.RlimitNoFile)
+	}
+
 	// override bind host/port from the console
 	if args.bindHost != "" {
 		config.BindHost = args.bindHost
@@ -285,6 +290,18 @@ func enableTLS13() {
 	}
 }
 
+// Set user-specified limit of how many fd's we can use
+// https://github.com/AdguardTeam/AdGuardHome/issues/659
+func setRlimit(val uint) {
+	var rlim syscall.Rlimit
+	rlim.Max = uint64(val)
+	rlim.Cur = uint64(val)
+	err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rlim)
+	if err != nil {
+		log.Error("Setrlimit() failed: %v", err)
+	}
+}
+
 func cleanup() {
 	log.Info("Stopping AdGuard Home")
 
diff --git a/config.go b/config.go
index 07466925..14ea6677 100644
--- a/config.go
+++ b/config.go
@@ -34,11 +34,13 @@ type configuration struct {
 	ourWorkingDir     string // Location of our directory, used to protect against CWD being somewhere else
 	firstRun          bool   // if set to true, don't run any services except HTTP web inteface, and serve only first-run html
 
-	BindHost  string             `yaml:"bind_host"` // BindHost is the IP address of the HTTP server to bind to
-	BindPort  int                `yaml:"bind_port"` // BindPort is the port the HTTP server
-	AuthName  string             `yaml:"auth_name"` // AuthName is the basic auth username
-	AuthPass  string             `yaml:"auth_pass"` // AuthPass is the basic auth password
-	Language  string             `yaml:"language"`  // two-letter ISO 639-1 language code
+	BindHost     string `yaml:"bind_host"`     // BindHost is the IP address of the HTTP server to bind to
+	BindPort     int    `yaml:"bind_port"`     // BindPort is the port the HTTP server
+	AuthName     string `yaml:"auth_name"`     // AuthName is the basic auth username
+	AuthPass     string `yaml:"auth_pass"`     // AuthPass is the basic auth password
+	Language     string `yaml:"language"`      // two-letter ISO 639-1 language code
+	RlimitNoFile uint   `yaml:"rlimit_nofile"` // Maximum number of opened fd's per process (0: default)
+
 	DNS       dnsConfig          `yaml:"dns"`
 	TLS       tlsConfig          `yaml:"tls"`
 	Filters   []filter           `yaml:"filters"`