Fixed user creation when group with the same id already exists

(cherry picked from commit 9fd6e070ff6d49b3a0fb4c4009a3072e2f007291)

README.md

@@ -14,7 +14,7 @@ docker run -d \
 ## Configuration
 
 Environment variables:
-- `USERS` - space and `|` separated list (optional, default: `ftp|alpineftp`)
+- `USERS` - space and `|` separated list (optional, default: `alpineftp|alpineftp`)
   - format `name1|password1|[folder1][|uid1] name2|password2|[folder2][|uid2]`
 - `ADDRESS` - external address witch clients can connect passive ports (optional, should resolve to ftp server ip address)
 - `MIN_PORT` - minimum port number to be used for passive connections (optional, default `21000`)

start_vsftpd.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 #Remove all ftp users
-#grep '/ftp/' /etc/passwd | cut -d':' -f1 | xargs -n1 deluser
+grep '/ftp/' /etc/passwd | cut -d':' -f1 | xargs -r -n1 deluser
 
 #Create users
 #USERS='name1|password1|[folder1][|uid1] name2|password2|[folder2][|uid2]'
@@ -14,11 +14,12 @@
 #Default user 'ftp' with password 'alpineftp'
 
 if [ -z "$USERS" ]; then
-  USERS="amin|alpineftp"
+  USERS="alpineftp|alpineftp"
 fi
 
 for i in $USERS ; do
   NAME=$(echo $i | cut -d'|' -f1)
+  GROUP=$NAME
   PASS=$(echo $i | cut -d'|' -f2)
   FOLDER=$(echo $i | cut -d'|' -f3)
   UID=$(echo $i | cut -d'|' -f4)
@@ -29,11 +30,16 @@ for i in $USERS ; do
 
   if [ ! -z "$UID" ]; then
     UID_OPT="-u $UID"
+    #Check if the group with the same ID already exists
+    GROUP=$(getent group $UID | cut -d: -f1)
+    if [ ! -z "$GROUP" ]; then
+      GROUP_OPT="-G $GROUP"
+    fi
   fi
 
-  echo -e "$PASS\n$PASS" | adduser -h $FOLDER -s /sbin/nologin $UID_OPT $NAME
+  echo -e "$PASS\n$PASS" | adduser -h $FOLDER -s /sbin/nologin $UID_OPT $GROUP_OPT $NAME
   mkdir -p $FOLDER
-  chown $NAME:$NAME $FOLDER
+  chown $NAME:$GROUP $FOLDER
   unset NAME PASS FOLDER UID
 done