Increasing nofiles limit on UNIX systems

src/github.com/getlantern/flashlight/main/increase_nofiles.go

@@ -0,0 +1,34 @@
+// +build !windows
+
+package main
+
+import (
+	"syscall"
+)
+
+const (
+	// 1024 is the default hard limit on Ubuntu, so let's not get greedier than
+	// that. On OS X, the default hard limit is unlimited.
+	DesiredNoFilesLimit = 1024
+)
+
+func init() {
+	// We increase the nofiles limit on UNIX platforms to avoid running out of
+	// file descriptors
+	var rLimit syscall.Rlimit
+	err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rLimit)
+	if err != nil {
+		log.Errorf("Error getting nofiles limit %v", err)
+		return
+	}
+	if rLimit.Cur > DesiredNoFilesLimit {
+		log.Debugf("Current nofiles soft limit of %d is enough", rLimit.Cur)
+		return
+	}
+	rLimit.Cur = DesiredNoFilesLimit
+	err = syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rLimit)
+	if err != nil {
+		log.Errorf("Unable to increase nofiles limit: %v", err)
+	}
+	log.Debugf("Changed nofiles soft limit to %d", rLimit.Cur)
+}