Add avifinfo_fuzz_fast.cc

avifinfo_fuzz.cc has good correctness coverage.
avifinfo_fuzz_fast.cc should test deeper branches and more values
because it is way faster (it tests the libavifinfo API once per input
string instead of once per input string byte).

Change-Id: I4fe6365cbcc82bad1491d026a6ccffbd9d8e2fdf

tests/avifinfo_fuzz_fast.cc

diff --git a/tests/avifinfo_fuzz_fast.cc b/tests/avifinfo_fuzz_fast.cc
new file mode 100644
index 0000000..17476b5
--- /dev/null
+++ b/tests/avifinfo_fuzz_fast.cc
@@ -0,0 +1,46 @@
+// Copyright (c) 2023, Alliance for Open Media. All rights reserved
+//
+// This source code is subject to the terms of the BSD 2 Clause License and
+// the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+// was not distributed with this source code in the LICENSE file, you can
+// obtain it at www.aomedia.org/license/software. If the Alliance for Open
+// Media Patent License 1.0 was not distributed with this source code in the
+// PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+
+#include "third_party/libavifinfo/avifinfo.h"
+
+//------------------------------------------------------------------------------
+
+// Test a random bitstream of random size, whether it is valid or not.
+// Let the fuzzer exercise any input as fast as possible, to expand as much
+// coverage as possible for a given corpus; hence the simple API use and the
+// limited correctness verifications.
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t data_size) {
+  const AvifInfoStatus status_identity = AvifInfoIdentify(data, data_size);
+
+  AvifInfoFeatures features;
+  const AvifInfoStatus status_features =
+      AvifInfoGetFeatures(data, data_size, &features);
+
+  if (status_features == kAvifInfoOk) {
+    if (status_identity != kAvifInfoOk) {
+      std::abort();
+    }
+    if (features.width == 0u || features.height == 0u ||
+        features.bit_depth == 0u || features.num_channels == 0u ||
+        !features.has_gainmap != !features.gainmap_item_id ||
+        !features.primary_item_id_location != !features.primary_item_id_bytes) {
+      std::abort();
+    }
+    if (features.primary_item_id_location &&
+        features.primary_item_id_location + features.primary_item_id_bytes >
+            data_size) {
+      std::abort();
+    }
+  }
+  return 0;
+}