travis: add gcovr summary for GCOV build

This gives a more useful summary, sorted by descending % coverage,
after the tests have run. The final numbers will give an idea if our
coverage is getting better or worse.

To keep the width sane we need to post process the file that the old
gcovr tool generates. This is done with a mix of sed, awk and column
in the scripts/coverage-summary.sh script.

As quite a lot of lines don't get covered at all we filter out all the
0% lines. If the file doesn't appear it is not being exercised.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

.travis.yml

@@ -38,6 +38,7 @@ addons:
       - libvte-2.90-dev
       - sparse
       - uuid-dev
+      - gcovr
 
 # The channel name "irc.oftc.net#qemu" is encrypted against qemu/qemu
 # to prevent IRC notifications from forks. This was created using:
@@ -86,6 +87,8 @@ matrix:
       compiler: clang
     # gprof/gcov are GCC features
     - env: CONFIG="--enable-gprof --enable-gcov --disable-pie --target-list=aarch64-softmmu,arm-softmmu,i386-softmmu,mips-softmmu,mips64-softmmu,ppc64-softmmu,riscv64-softmmu,s390x-softmmu,x86_64-softmmu"
+      after_success:
+        - ${SRC_DIR}/scripts/travis/coverage-summary.sh
       compiler: gcc
     # We manually include builds which we disable "make check" for
     - env: CONFIG="--enable-debug --enable-tcg-interpreter"

MAINTAINERS

@@ -2166,6 +2166,7 @@ R: Philippe Mathieu-Daudé <f4bug@amsat.org>
 L: qemu-devel@nongnu.org
 S: Maintained
 F: .travis.yml
+F: scripts/travis/
 F: .shippable.yml
 F: tests/docker/
 F: tests/vm/

scripts/travis/coverage-summary.sh

@@ -0,0 +1,27 @@
+#!/bin/sh
+#
+# Author: Alex Bennée <alex.bennee@linaro.org>
+#
+# Summerise the state of code coverage with gcovr and tweak the output
+# to be more sane on Travis hosts. As we expect to be executed on a
+# throw away CI instance we do spam temp files all over the shop. You
+# most likely don't want to execute this script but just call gcovr
+# directly. See also "make coverage-report"
+#
+# This code is licensed under the GPL version 2 or later.  See
+# the COPYING file in the top-level directory.
+
+# first generate the coverage report
+gcovr -p -o raw-report.txt
+
+# strip the full-path and line markers
+sed s@$PWD\/@@ raw-report.txt | sed s/[0-9]\*[,-]//g > simplified.txt
+
+# reflow lines that got split
+awk '/.[ch]$/ { printf("%s", $0); next } 1' simplified.txt > rejoined.txt
+
+# columnify
+column -t rejoined.txt > final.txt
+
+# and dump, stripping out 0% coverage
+grep -v "0%" final.txt