Add GitHub Actions for this pre-lab

.github/workflows/gtest.yml

@@ -0,0 +1,27 @@
+name: gtest
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Cache gtest library
+      uses: actions/cache@v2
+      env:
+        cache-name: cache-gtest-lib
+      with:
+        key: $${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('/usr/local/lib/libgtest.a') }}
+        path: /usr/local/lib/libgtest.a
+        restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+    - name: Install gtest manually
+      run: sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake CMakeLists.txt && sudo make && sudo cp lib/*.a /usr/lib && sudo ln -s /usr/lib/libgtest.a /usr/local/lib/libgtest.a && sudo ln -s /usr/lib/libgtest_main.a /usr/local/lib/libgtest_main.a
+    - name: Check out the code
+      uses: actions/checkout@v2
+    - name: Compile test code
+      run: g++ -Wall -g -o check_whitespace_test check_whitespace.c check_whitespace_test.cpp -lgtest -pthread
+    - name: Run test
+      run: ./check_whitespace_test

.github/workflows/main_valgrind.yml

@@ -0,0 +1,29 @@
+name: main-valgrind
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Cache gtest library
+      uses: actions/cache@v2
+      env:
+        cache-name: cache-gtest-lib
+      with:
+        key: $${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('/usr/local/lib/libgtest.a') }}
+        path: /usr/local/lib/libgtest.a
+        restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+    - name: Install gtest manually
+      run: sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake CMakeLists.txt && sudo make && sudo cp lib/*.a /usr/lib && sudo ln -s /usr/lib/libgtest.a /usr/local/lib/libgtest.a && sudo ln -s /usr/lib/libgtest_main.a /usr/local/lib/libgtest_main.a
+    - name: Install valgrind
+      run: sudo apt-get install -y valgrind
+    - name: Check out the code
+      uses: actions/checkout@v2
+    - name: Compile code
+      run: gcc -Wall -g -o check_whitespace check_whitespace.c main.c
+    - name: Run test
+      run: valgrind -v --leak-check=full --show-leak-kinds=all --error-exitcode=1 ./check_whitespace < main.c

.github/workflows/test_valgrind.yml

@@ -0,0 +1,29 @@
+name: test-valgrind
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Cache gtest library
+      uses: actions/cache@v2
+      env:
+        cache-name: cache-gtest-lib
+      with:
+        key: $${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('/usr/local/lib/libgtest.a') }}
+        path: /usr/local/lib/libgtest.a
+        restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+    - name: Install gtest manually
+      run: sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake CMakeLists.txt && sudo make && sudo cp lib/*.a /usr/lib && sudo ln -s /usr/lib/libgtest.a /usr/local/lib/libgtest.a && sudo ln -s /usr/lib/libgtest_main.a /usr/local/lib/libgtest_main.a
+    - name: Install valgrind
+      run: sudo apt-get install -y valgrind
+    - name: Check out the code
+      uses: actions/checkout@v2
+    - name: Compile code
+      run: g++ -Wall -g -o check_whitespace_test check_whitespace.c check_whitespace_test.cpp -lgtest -pthread
+    - name: Run test
+      run: valgrind -v --leak-check=full --show-leak-kinds=all --error-exitcode=1 ./check_whitespace_test

README.md

@@ -1,12 +1,18 @@
 # C-programming-pre-lab <!-- omit in toc -->
 
+[![Tests](../../workflows/gtest/badge.svg)](../../actions?query=workflow%3A"gtest")
+[![Main Valgrind](../../workflows/main-valgrind/badge.svg)](../../actions?query=workflow%3A"main-valgrind")
+[![Test Valgrind](../../workflows/test-valgrind/badge.svg)](../../actions?query=workflow%3A"test-valgrind")
+
+
 This is a pre-lab to get you started started on compiling and running C programs
 and using `valgrind` to identify memory leaks.
 
 - [Background](#background)
   - [Compiling and running a C program](#compiling-and-running-a-c-program)
   - [Compiling and running the tests](#compiling-and-running-the-tests)
   - [Using valgrind to find memory leaks](#using-valgrind-to-find-memory-leaks)
+- [GitHub Actions and badges](#github-actions-and-badges)
 - [What to do](#what-to-do)
 
 ## Background
@@ -313,6 +319,42 @@ Once you have everything happy, you will hopefully get a line like:
 
 at the end indicating that you now have 0 errors and all is well.
 
+## GitHub Actions and badges
+
+We've set up GitHub Actions to automatically run three checks on your
+code every time you push changes to GitHub:
+
+- The code compiles and the tests pass.
+- Valgrind returns no errors when running the `main` function.
+- Valgrind returns no errors when running the test code.
+
+You should be able to see the status of these in a commit or pull request
+in GitHub. Here, for example, is a status from a pull request:
+
+![Screen grab of GitHub Action status showing success, failure, and pending](images/GitHub_action_status.png)
+
+We have all three possible status indicators here:
+
+- The red x indicates a failing check
+- The orange dot indicates a check that's still in progress
+- The green checkmark indicates a check that passed
+
+When you initially check out the code for the pre-lab, the `gtest`
+check should pass (the tests pass), but the other two should fail
+because there are memory issues with both the `check_whitespace`
+`main()` and the tests.
+
+We have also added three badges to the top of this README that indicate
+the status of each of these three status checks. The tests badge should
+be green from the beginning (and stay green throughout the process).
+The two `valgrind` badges will both start off red (because the `valgrind`
+checks fail initially) but turn green after you've fixed the memory
+management issue.
+
+> :warning: The badges won't update instantly, so don't fret if
+> your status checks are green but the badge is still red. That
+> should update in a few minutes.
+
 ## What to do
 
 - [ ] Compile the program `check_whitespace`