add clang-format checker and travis hooks

.travis.yml

@@ -3,10 +3,30 @@ sudo: required
 
 before_script:
    - sudo apt-get -qq update
-   - sudo apt-get install -qq build-essential cmake libfftw3-dev libmbedtls-dev libpcsclite-dev libboost-program-options-dev libconfig++-dev libsctp-dev
+   - sudo apt-get install -qq build-essential cmake libfftw3-dev libmbedtls-dev libpcsclite-dev libboost-program-options-dev libconfig++-dev libsctp-dev colordiff
 
 language: cpp
+
+addons:
+  apt:
+    sources:
+      - llvm-toolchain-trusty-8
+      - key_url: 'http://apt.llvm.org/llvm-snapshot.gpg.key'
+    packages:
+      - clang-format-8
+
 script:
+ - sudo ln -s /usr/bin/clang-format-diff-8 /usr/bin/clang-format-diff
+ - git remote set-branches --add origin master
+ - git fetch
+ - |
+   if [[ "$TRAVIS_PULL_REQUEST" != "false" ]]; then
+     # Run only for PRs because target branch is needed to do the clang-format check
+     echo "Checking clang-format between TRAVIS_BRANCH=$TRAVIS_BRANCH and TRAVIS_PULL_REQUEST_BRANCH=$TRAVIS_PULL_REQUEST_BRANCH"
+     ./run-clang-format-diff.sh "$TRAVIS_BRANCH" "$TRAVIS_PULL_REQUEST_BRANCH"
+   else
+     echo "Skipping clang-format check"
+   fi
  - mkdir build
  - cd build
  - cmake -DRF_FOUND=True ..

run-clang-format-diff.sh

@@ -0,0 +1,61 @@
+#!/bin/bash
+# Copyright 2013-2019 Software Radio Systems Limited
+#
+# This file is part of srsLTE.
+#
+# srsLTE is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of
+# the License, or (at your option) any later version.
+#
+# srsLTE is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# A copy of the GNU Affero General Public License can be found in
+# the LICENSE file in the top-level directory of this distribution
+# and at http://www.gnu.org/licenses/.
+#
+ 
+# make sure all commands are echoed
+#set -x
+set -o pipefail
+
+if ([ ! $1 ])
+then
+  echo "Please call script with target branch name or git hash to perform diff with."
+  echo "E.g. ./run-clang-format-diff.sh [HASH]"
+  exit 1
+fi
+
+# check for apps
+app1=$(which clang-format-diff)
+app2=$(which git)
+app3=$(which colordiff)
+if ([ ! -x "$app1" ] || [ ! -x "$app2" ] || [ ! -x "$app3" ])
+then
+  echo "Please install clang-format-diff, git and colordiff"
+  exit 1
+fi
+
+target=$1
+
+echo "Running code format check between ${target} and ${commit} .."
+
+# run clang-format
+diff="$(git diff ${target} | clang-format-diff -p1 | python3 -c 'data = open(0).read(); print(data); exit(1 if data else 0)')"
+
+# safe return code
+ret=$?
+
+if ([ $ret == "0" ])
+then
+  echo "Code formatting is correct."
+else
+  echo "The following code seems to be not formatted correctly:"
+  # print colorized version
+  echo "${diff}" | colordiff
+fi
+
+exit ${ret}