Adding new travis job for testing shell-scripts

CI job uses shellcheck csdiff and csgrep to check changes between
merge branch and PR commits. IT ignores existing "warnings and notes"
but fail on added "errors, warnings or notes".

NOTE: CI job checks only shell-scripts present in .ci/script-list.txt
file

4 files changed, 141 insertions, 2 deletions

diff --git a/.ci/check-shell.sh b/.ci/check-shell.sh
new file mode 100755
index 00000000..a4ea3c52
--- /dev/null
+++ b/.ci/check-shell.sh
@@ -0,0 +1,70 @@
+#!/bin/bash
+
+. ./.ci/functions.sh
+
+# ------------ #
+#  FILE PATHS  #
+# ------------ #
+
+# https://medium.com/@joey_9999/how-to-only-lint-files-a-git-pull-request-modifies-3f02254ec5e0
+# get names of files from PR (excluding deleted files)
+# TRAVIS_COMMIT_RANGE - HEAD of destination branch ... HEAD of PR branch
+git diff --name-only --diff-filter=db "${TRAVIS_COMMIT_RANGE}" > ../pr-changes.txt
+
+# Find modified shell scripts
+readarray list_of_changes < <(grep "^[^#]" ../pr-changes.txt)
+list_of_changed_scripts=()
+for file in "${list_of_changes[@]}"; do
+  # https://stackoverflow.com/questions/19345872/how-to-remove-a-newline-from-a-string-in-bash
+  # Remove new line and add ./ at the beginning
+  is_it_script "$file" && list_of_changed_scripts+=("./${file//[$'\t\r\n ']}")
+done
+
+echo "Changed shell scripts:"
+echo "${list_of_changed_scripts[@]}"
+echo "------------"
+
+# ------------ #
+#  SHELLCHECK  #
+# ------------ #
+
+# sed part is to edit shellcheck output so csdiff/csgrep knows it is shellcheck output (--format=gcc)
+shellcheck --format=gcc "${list_of_changed_scripts[@]}" | sed -e 's|$| <--[shellcheck]|' > ../pr-br-shellcheck.err
+
+# make destination branch
+[[ ${TRAVIS_COMMIT_RANGE} =~ ^([0-9|a-f]*?)\. ]] && git checkout -b ci_br_dest "${BASH_REMATCH[1]}"
+
+shellcheck --format=gcc "${list_of_changed_scripts[@]}" | sed -e 's|$| <--[shellcheck]|' > ../dest-br-shellcheck.err
+
+# ------------ #
+#  VALIDATION  #
+# ------------ #
+
+exitstatus=0
+
+# Check output for Fixes
+csdiff --fixed "../dest-br-shellcheck.err" "../pr-br-shellcheck.err" > ../fixes.log
+if [ "$(cat ../fixes.log | wc -l)" -ne 0 ]; then
+  echo "Fixed bugs:" 
+  csgrep ../fixes.log
+  echo "------------"
+else
+  echo "No Fixes!"
+  echo "------------"
+fi
+
+# Check output for added bugs
+csdiff --fixed "../pr-br-shellcheck.err" "../dest-br-shellcheck.err" > ../bugs.log
+if [ "$(cat ../bugs.log | wc -l)" -ne 0 ]; then
+  echo "Added bugs, NEED INSPECTION:" 
+  csgrep ../bugs.log
+  echo "------------"
+  exitstatus=1
+else
+  echo "No bugs added Yay!" 
+  echo "------------"
+  exitstatus=0
+fi
+
+exit $exitstatus
+
diff --git a/.ci/functions.sh b/.ci/functions.sh
new file mode 100644
index 00000000..300f92df
--- /dev/null
+++ b/.ci/functions.sh
@@ -0,0 +1,9 @@
+# Function to check whether input param is on list of shell scripts
+# $1 - <string> absolute path to file
+is_it_script () {
+  [ $# -eq 0 ] && return 1
+  
+  readarray list_of_scripts < ./.ci/script-list.txt
+  echo "${list_of_scripts[@]}" | grep --silent "$1" && return 0
+}
+
diff --git a/.ci/script-list.txt b/.ci/script-list.txt
new file mode 100644
index 00000000..7323ceb7
--- /dev/null
+++ b/.ci/script-list.txt
@@ -0,0 +1,36 @@
+# Tracker of all shell scripts in this repository
+etc/rc.d/init.d/functions
+etc/rc.d/init.d/network
+network-scripts/ifdown-bnep
+network-scripts/ifdown-ippp
+network-scripts/ifdown-post
+network-scripts/ifdown-sit
+network-scripts/ifup
+network-scripts/ifup-bnep
+network-scripts/ifup-eth
+network-scripts/ifup-ipv6
+network-scripts/ifup-plusb
+network-scripts/ifup-routes
+network-scripts/ifup-tunnel
+network-scripts/init.ipv6-global
+network-scripts/network-functions-ipv6
+network-scripts/ifdown
+network-scripts/ifdown-eth
+network-scripts/ifdown-ipv6
+network-scripts/ifdown-routes
+network-scripts/ifdown-tunnel
+network-scripts/ifup-aliases
+network-scripts/ifup-ctc
+network-scripts/ifup-ippp
+network-scripts/ifup-plip
+network-scripts/ifup-post
+network-scripts/ifup-sit
+network-scripts/ifup-wireless
+network-scripts/network-functions
+usr/libexec/import-state
+usr/libexec/loadmodules
+usr/libexec/netconsole
+usr/libexec/readonly-root
+usr/sbin/service
+.ci/check-shell.sh
+.ci/functions.sh
diff --git a/.travis.yml b/.travis.yml
index b75e9141..ee431240 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,11 +2,35 @@
 sudo: false
 dist: trusty
 
-language: c
-script: make all && make install DESTDIR=/tmp/initscripts
+git:
+  depth: 2
+
+## Source - 01: https://github.com/kdudka/csdiff/blob/master/.travis.yml  
+before_install:
+  - sudo apt-get update
+  - sudo apt-get install apt-transport-https
+  - echo "deb https://kdudka.fedorapeople.org/csbuild trusty contrib" | sudo tee -a /etc/apt/sources.list
+  - sudo apt-get update
+
+install:
+  - sudo apt-get install cmake help2man libboost-dev libboost-filesystem-dev libboost-program-options-dev libboost-python-dev libboost-regex-dev tree
+  - sudo apt-get install -y --force-yes csbuild
+## End - 01
 
 # We need to install the libpopt dependency without sudo:
 addons:
   apt:
     packages:
       libpopt-dev
+
+matrix:
+  include:
+    - language: shell
+      script: 
+        - 'if [ "$TRAVIS_PULL_REQUEST" != "false" ]; then bash ./.ci/check-shell.sh; fi'
+    - language: c
+      script: make all && make install DESTDIR=/tmp/initscripts
+
+notifications:
+  email: false
+