From a34180459af91c97b1b0e885a69dec0e69e659db Mon Sep 17 00:00:00 2001
From: Steven Soroka <ssoroka@influxdata.com>
Date: Fri, 28 Feb 2020 13:58:56 -0500
Subject: [PATCH] Close stdin on exit in execd input

---
 CHANGELOG.md                   |  1 +
 plugins/inputs/execd/README.md |  5 +++--
 plugins/inputs/execd/execd.go  | 10 ++++++----
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 40bf18e9b..5b03ca072 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 - [infiniband](/plugins/inputs/infiniband/README.md) - Contributed by @willfurnell
 - [modbus](/plugins/inputs/modbus/README.md) - Contributed by @garciaolais
 - [monit](/plugins/inputs/monit/README.md) - Contributed by @SirishaGopigiri
+- [execd](/plugins/inputs/execd/README.md) - Contributed by @jgraichen
 
 #### New Processors
 
diff --git a/plugins/inputs/execd/README.md b/plugins/inputs/execd/README.md
index 1205fdd56..022311924 100644
--- a/plugins/inputs/execd/README.md
+++ b/plugins/inputs/execd/README.md
@@ -1,6 +1,7 @@
 # Execd Input Plugin
 
-The `execd` plugin runs an external program as a daemon. The programs must output metrics in any one of the accepted [Input Data Formats](https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md) on its standard output.
+The `execd` plugin runs an external program as a daemon. The programs must output metrics in any one of the accepted 
+[Input Data Formats](https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md) on its standard output.
 
 The `signal` can be configured to send a signal the running daemon on each collection interval.
 
@@ -9,11 +10,11 @@ Program output on standard error is mirrored to the telegraf log.
 ### Configuration:
 
 ```toml
+[[inputs.execd]]
   ## Program to run as daemon
   command = ["telegraf-smartctl", "-d", "/dev/sda"]
 
   ## Define how the process is signaled on each collection interval.
-
   ## Valid values are:
   ##   "none"    : Do not signal anything.
   ##              The process must output metrics by itself.
diff --git a/plugins/inputs/execd/execd.go b/plugins/inputs/execd/execd.go
index 0d1fc7cc5..e852d045e 100644
--- a/plugins/inputs/execd/execd.go
+++ b/plugins/inputs/execd/execd.go
@@ -21,12 +21,13 @@ const sampleConfig = `
   command = ["telegraf-smartctl", "-d", "/dev/sda"]
 
   ## Define how the process is signaled on each collection interval.
-
   ## Valid values are:
   ##   "none"   : Do not signal anything.
   ##              The process must output metrics by itself.
-  ##   "STDIN"  : Send a newline on STDIN.
-  ##   "SIGHUP" : Send a HUP signal. Not available on Windows.
+  ##   "STDIN"   : Send a newline on STDIN.
+  ##   "SIGHUP"  : Send a HUP signal. Not available on Windows.
+  ##   "SIGUSR1" : Send a USR1 signal. Not available on Windows.
+  ##   "SIGUSR2" : Send a USR2 signal. Not available on Windows.
   signal = "none"
 
   ## Delay before the process is restarted after an unexpected termination
@@ -100,9 +101,10 @@ func (e *Execd) cmdLoop(ctx context.Context) {
 
 		select {
 		case <-ctx.Done():
+			e.stdin.Close()
 			// Immediately exit process but with a graceful shutdown
 			// period before killing
-			internal.WaitTimeout(e.cmd, 0)
+			internal.WaitTimeout(e.cmd, 200*time.Millisecond)
 			return
 		case err := <-done:
 			log.Printf("E! [inputs.execd] Process %s terminated: %s", e.Command, err)