fuzzing.yml: Evaluate one single fuzzer at a time, in parallel

.github/workflows/fuzzing.yml

@@ -42,7 +42,15 @@ permissions:
 jobs:
   run_fuzzers:
     name: Run fuzzing regression tests
+    strategy:
+      fail-fast: false
+      matrix:
+        fuzzer:
+          - xml_parse_fuzzer_UTF-8
+          - xml_parsebuffer_fuzzer_UTF-16LE
     runs-on: ubuntu-24.04
+    env:
+      fuzzer: ${{ matrix.fuzzer }}
     steps:
     - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
 
@@ -100,14 +108,10 @@ jobs:
       run: |-
         set -x
         cd expat/build/
+        wget -q -O corpus.zip "https://storage.googleapis.com/expat-backup.clusterfuzz-external.appspot.com/corpus/libFuzzer/expat_${fuzzer}/public.zip"
+        unzip -q -d corpus/ corpus.zip
 
-        wget -q -O expat_corpus_UTF-8.zip    https://storage.googleapis.com/expat-backup.clusterfuzz-external.appspot.com/corpus/libFuzzer/expat_xml_parse_fuzzer_UTF-8/public.zip
-        wget -q -O expat_corpus_UTF-16LE.zip https://storage.googleapis.com/expat-backup.clusterfuzz-external.appspot.com/corpus/libFuzzer/expat_xml_parse_fuzzer_UTF-16LE/public.zip
-
-        unzip -q -d corpus_UTF-8    expat_corpus_UTF-8.zip
-        unzip -q -d corpus_UTF-16LE expat_corpus_UTF-16LE.zip
-
-    - name: Run fuzzing regression tests (10+ minutes)
+    - name: Run fuzzing regression tests (1 to 5 minutes)
       run: |
         fuzz_args=(
             -jobs=$(nproc)
@@ -122,26 +126,17 @@ jobs:
         mkdir coverage/
         export LLVM_PROFILE_FILE=coverage/expat-%p.profraw
 
-        #           vvvvv
-        find corpus_UTF-8/ -type f | sort | xargs \
-            fuzz/xml_parse_fuzzer_UTF-8 "${fuzz_args[@]}"
-        #                         ^^^^^
-        #           vvvvvvvv
-        find corpus_UTF-16LE/ -type f | sort | xargs \
-            fuzz/xml_parsebuffer_fuzzer_UTF-16LE "${fuzz_args[@]}"
-        #                 ^^^^^^        ^^^^^^^^
+        find corpus/ -type f | sort | xargs "fuzz/${fuzzer}" "${fuzz_args[@]}"
 
     - name: Store fuzzing logs of last batch
       uses: actions/upload-artifact@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08  # v4.6.0
       with:
-        name: expat_fuzzing_logs_last_${{ github.sha }}
+        name: expat_fuzzing_logs_last_${{ matrix.fuzzer }}_${{ github.sha }}
         path: expat/build/fuzz-*.log
         if-no-files-found: error
 
     - name: Render coverage report
       run: |
-        fuzzer=xml_parse_fuzzer_UTF-8  # could be any of them
-
         set -x -o pipefail
         cd expat/build/
 
@@ -156,6 +151,6 @@ jobs:
     - name: Store coverage report
       uses: actions/upload-artifact@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08  # v4.6.0
       with:
-        name: expat_fuzzing_coverage_${{ github.sha }}
+        name: expat_fuzzing_coverage_${{ matrix.fuzzer }}_${{ github.sha }}
         path: expat/build/coverage/
         if-no-files-found: error