From: Urban Wallasch <urban.wallasch@freenet.de>
Date: Wed, 10 Apr 2019 21:04:16 +0000 (+0200)
Subject: * Added options to set connection and worker queue limits.
X-Git-Url: https://git.packet-gain.de/?a=commitdiff_plain;h=171dae88b5722fb868dc3f389a0bed15ff2ed43c;p=gogopherd.git

* Added options to set connection and worker queue limits.
* Improved usage strings of several flags.
---

diff --git a/README.md b/README.md
index b1de47d..c078f28 100644
--- a/README.md
+++ b/README.md
@@ -65,6 +65,18 @@ options:
   -i string
       interface to bind to; empty for any (default "localhost")
 
+  -lb int
+      set connection burst limit (default 50)
+
+  -lc int
+      set connections per second rate limit  (default 5)
+
+  -lj int
+      set worker job queue size (default 50)
+
+  -lw int
+      set number of worker threads (default 6)
+
   -p string
       TCP port to listen on (default "7070")
 
diff --git a/config.go b/config.go
index 129ee8a..6e5ea1d 100644
--- a/config.go
+++ b/config.go
@@ -32,6 +32,10 @@ var cfg = struct {
 	showdot bool
 	indexes bool
 	timeout int
+	crate   int
+	cburst  int
+	njobs   int
+	nworker int
 	logfile string
 	verbose bool
 }{
@@ -46,6 +50,10 @@ var cfg = struct {
 	showdot: false,
 	indexes: false,
 	timeout: 60,
+	crate:   5,
+	cburst:  50,
+	nworker: 6,
+	njobs:   50,
 	logfile: "",
 	verbose: false,
 }
@@ -89,6 +97,14 @@ func parseConfigFile(filename string) error {
 			cfg.indexes = strToBool(val)
 		case "timeout":
 			cfg.timeout, _ = strconv.Atoi(val)
+		case "crate":
+			cfg.crate, _ = strconv.Atoi(val)
+		case "cburst":
+			cfg.cburst, _ = strconv.Atoi(val)
+		case "nworker":
+			cfg.nworker, _ = strconv.Atoi(val)
+		case "njobs":
+			cfg.njobs, _ = strconv.Atoi(val)
 		case "logfile":
 			cfg.logfile = val
 		case "verbose":
@@ -104,20 +120,24 @@ func initialize() {
 	var err error
 	help := false
 	cfgfile := ""
-	flag.StringVar(&cfgfile, "c", cfgfile, "configuration file")
+	flag.StringVar(&cfgfile, "c", cfgfile, "read configuration from `file`")
 	flag.StringVar(&cfg.iface, "i", cfg.iface, "interface to bind to; empty for any")
-	flag.StringVar(&cfg.port, "p", cfg.port, "TCP port to listen on")
+	flag.StringVar(&cfg.port, "p", cfg.port, "TCP `port` to listen on")
 	flag.StringVar(&cfg.fqdn, "f", cfg.fqdn, "fully qualified domain name")
-	flag.StringVar(&cfg.docroot, "r", cfg.docroot, "document root directory")
-	flag.StringVar(&cfg.idxpage, "I", cfg.idxpage, "directory index page")
-	flag.StringVar(&cfg.header, "H", cfg.header, "header file to prepend to generated pages")
-	flag.StringVar(&cfg.footer, "F", cfg.footer, "footer file to append to generated pages")
-	flag.BoolVar(&help, "h", help, "show this help page")
+	flag.StringVar(&cfg.docroot, "r", cfg.docroot, "document root `directory`")
+	flag.StringVar(&cfg.idxpage, "I", cfg.idxpage, "directory index `file` name")
+	flag.StringVar(&cfg.header, "H", cfg.header, "header: prepend contents of `file` to generated pages")
+	flag.StringVar(&cfg.footer, "F", cfg.footer, "footer: append contents of `file` to generated pages")
+	flag.BoolVar(&help, "h", help, "display this help message")
 	flag.BoolVar(&cfg.fsymln, "s", cfg.fsymln, "follow symbolic links")
 	flag.BoolVar(&cfg.showdot, "d", cfg.showdot, "allow access to dotfiles")
 	flag.BoolVar(&cfg.indexes, "D", cfg.indexes, "allow generated directory indexes")
-	flag.IntVar(&cfg.timeout, "t", cfg.timeout, "connection read/write timeout in seconds")
-	flag.StringVar(&cfg.logfile, "L", cfg.logfile, "write log to file; empty for stderr")
+	flag.IntVar(&cfg.timeout, "t", cfg.timeout, "connection read/write timeout in `seconds`")
+	flag.IntVar(&cfg.crate, "lc", cfg.crate, "set connections per second rate limit to `num`")
+	flag.IntVar(&cfg.cburst, "lb", cfg.cburst, "set connection burst limit to `num`")
+	flag.IntVar(&cfg.nworker, "lw", cfg.nworker, "set number of worker threads to `num`")
+	flag.IntVar(&cfg.njobs, "lj", cfg.njobs, "set worker job queue size to `num`")
+	flag.StringVar(&cfg.logfile, "L", cfg.logfile, "write log to `file`; empty for stderr")
 	flag.BoolVar(&cfg.verbose, "v", cfg.verbose, "produce verbose output")
 	flag.Parse()
 	if help {
@@ -163,6 +183,10 @@ func initialize() {
 	tracer.Print("showdot: ", cfg.showdot)
 	tracer.Print("indexes: ", cfg.indexes)
 	tracer.Print("timeout: ", cfg.timeout)
+	tracer.Print("crate:   ", cfg.crate)
+	tracer.Print("cburst:  ", cfg.cburst)
+	tracer.Print("nworker: ", cfg.nworker)
+	tracer.Print("njobs:   ", cfg.njobs)
 	tracer.Print("verbose: ", cfg.verbose)
 	tracer.Print("gogopherd version ", version)
 }
diff --git a/gogopherd.cfg.example b/gogopherd.cfg.example
index 64710ac..8dfa9a8 100644
--- a/gogopherd.cfg.example
+++ b/gogopherd.cfg.example
@@ -26,6 +26,14 @@ indexes = true
 
 # Connection read and write timeout in seconds
 timeout =  60
+# Connections per second rate limit
+crate = 5
+# Connection burst limit
+cburst = 50
+# Number of worker threads
+nworker = 6
+# Worker job queue size
+njobs = 50
 
 # Log to file; leave empty for stderr
 logfile = ""
diff --git a/gogopherd.go b/gogopherd.go
index 0b029db..8b8b577 100644
--- a/gogopherd.go
+++ b/gogopherd.go
@@ -249,12 +249,9 @@ func handleRequest(conn net.Conn) {
 
 func serveTCP(listener *net.TCPListener) {
 	// connection rate limiter
-	rate := 5
-	burst := 50
-	interval := time.Second / time.Duration(rate)
-	tick := time.NewTicker(interval)
+	tick := time.NewTicker(time.Second / time.Duration(cfg.crate))
 	defer tick.Stop()
-	throttle := make(chan time.Time, burst)
+	throttle := make(chan time.Time, cfg.cburst)
 	go func() {
 		for t := range tick.C {
 			select {
@@ -264,10 +261,8 @@ func serveTCP(listener *net.TCPListener) {
 		}
 	}()
 	// worker and job queue setup
-	nworker := 5
-	njobs := 50
-	jobs := make(chan net.Conn, njobs)
-	for w := 1; w <= nworker; w++ {
+	jobs := make(chan net.Conn, cfg.njobs)
+	for w := 1; w <= cfg.nworker; w++ {
 		go func(id int, jobs <-chan net.Conn) {
 			for j := range jobs {
 				tracer.Print("worker id ", id, ": ", j.RemoteAddr())