Split benchmarks and test tools into separate targets.

This lets us remove main() from snappy_bench.cc and snappy_unittest.cc,
which simplifies integrating these tests and benchmarks with other
suites.

PiperOrigin-RevId: 347857427

snappy_test_data.cc

@@ -0,0 +1,57 @@
+// Copyright 2020 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Support code for reading test data.
+
+#include "snappy_test_data.h"
+
+#include <cstddef>
+#include <cstdlib>
+#include <string>
+
+#include "snappy-test.h"
+
+namespace snappy {
+
+std::string ReadTestDataFile(const char* base, size_t size_limit) {
+  std::string srcdir;
+  const char* srcdir_env = std::getenv("srcdir");  // This is set by Automake.
+  if (srcdir_env) {
+    srcdir = std::string(srcdir_env) + "/";
+  }
+
+  std::string contents;
+  CHECK_OK(file::GetContents(srcdir + "testdata/" + base, &contents,
+                             file::Defaults()));
+  if (size_limit > 0) {
+    contents = contents.substr(0, size_limit);
+  }
+  return contents;
+}
+
+}  // namespace snappy