ci/prepare-linux.sh: do not run setcap unless necessary

diff --git a/ci/prepare-linux.sh b/ci/prepare-linux.sh
index 4af6d84972c7df7b2b9bc4d462e9e83115c50edf..51ca7b3e6daa4a2b1444265aec59796e809f88ff 100755 (executable)
--- a/ci/prepare-linux.sh
+++ b/ci/prepare-linux.sh
@@ -1,6 +1,8 @@
 #!/bin/bash
 
-sudo setcap cap_net_raw,cap_net_admin+ep src/fping
+if ! /usr/sbin/getcap src/fping | grep -q "cap_net_admin,cap_net_raw=ep"; then
+    sudo setcap cap_net_raw,cap_net_admin+ep src/fping
+fi
 
 if [ -d "$PWD/src" ]; then
     if [[ ":$PATH:" != *":$PWD/src:"* ]]; then