[bench] add streams findbyte

Author: glozow

src/Makefile.bench.include

@@ -47,6 +47,7 @@ bench_bench_bitcoin_SOURCES = \
   bench/rollingbloom.cpp \
   bench/rpc_blockchain.cpp \
   bench/rpc_mempool.cpp \
+  bench/streams_findbyte.cpp \
   bench/strencodings.cpp \
   bench/util_time.cpp \
   bench/verify_script.cpp

src/bench/streams_findbyte.cpp

@@ -0,0 +1,31 @@
+// Copyright (c) 2023 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <bench/bench.h>
+
+#include <util/fs.h>
+#include <streams.h>
+
+static void FindByte(benchmark::Bench& bench)
+{
+    // Setup
+    FILE* file = fsbridge::fopen("streams_tmp", "w+b");
+    const size_t file_size = 200;
+    uint8_t data[file_size] = {0};
+    data[file_size-1] = 1;
+    fwrite(&data, sizeof(uint8_t), file_size, file);
+    rewind(file);
+    CBufferedFile bf(file, /*nBufSize=*/file_size + 1, /*nRewindIn=*/file_size, 0, 0);
+
+    bench.run([&] {
+        bf.SetPos(0);
+        bf.FindByte(1);
+    });
+
+    // Cleanup
+    bf.fclose();
+    fs::remove("streams_tmp");
+}
+
+BENCHMARK(FindByte, benchmark::PriorityLevel::HIGH);