CI/GHA: test against libseccomp 2.5.2 and HEAD

Instead of testing against whatever version of libseccomp the distro
(Ubuntu 20.04 in this case) provides, do compile and test against the
latest released version, 2.5.2.

While at it, it's relatively easy to enable testing against git tip as
well, so implement it as well.

Signed-off-by: Kir Kolyshkin <[email protected]>

Author: kolyshkin

.github/workflows/test.yml

@@ -16,23 +16,47 @@ jobs:
       fail-fast: false
       matrix:
         go-version: [1.15.x, 1.16.x, 1.17.x]
+        libseccomp: ["v2.5.2", "HEAD"]
 
     steps:
 
     - name: checkout
       uses: actions/checkout@v2
 
-    - name: install deps
-      run: |
-        sudo apt -q update
-        sudo apt -q install libseccomp-dev
-
     - name: install go ${{ matrix.go-version }}
       uses: actions/setup-go@v2
       with:
         stable: '!contains(${{ matrix.go-version }}, "beta") && !contains(${{ matrix.go-version }}, "rc")'
         go-version: ${{ matrix.go-version }}
 
+    - name: build libseccomp ${{ matrix.libseccomp }}
+      run: |
+        set -x
+        sudo apt -qq update
+        sudo apt -qq install gperf
+        git clone https://github.com/seccomp/libseccomp
+        cd libseccomp
+        git checkout ${{ matrix.libseccomp }}
+        # In main branch, configure.ac sets libseccomp version to 0.0.0, which
+        # results in error when compiling libseccomp-golang. While 0.0.0 is
+        # there for a reason, here we need to build and test against HEAD, so
+        # set it to a suitable value.
+        # Version 2.99.999 is used because:
+        #  - version >= current is needed;
+        #  - no need to change it after a new release (until 3.0.0);
+        #  - chances are very high such version won't ever exist;
+        #  - it is easy to spot in tests output.
+        sed -i '/^AC_INIT(/s/0\.0\.0/2.99.999/' configure.ac
+        ./autogen.sh
+        ./configure --prefix=/usr/local --libdir=/usr/local/lib
+        make
+        sudo make install
+        cd -
+        rm -rf libseccomp
+        # For the next steps to use the compiled library, set these env vars.
+        echo "PKG_CONFIG_DIR=/usr/local/lib/pkgconfig" >> $GITHUB_ENV
+        echo "LD_LIBRARY_PATH=/usr/local/lib" >> $GITHUB_ENV
+
     - name: build
       run: make check-build