backport: bitcoin#28060, bitcoin#28090, bitcoin#28108, bitcoin#28204

src/.clang-tidy

@@ -5,6 +5,7 @@ bugprone-use-after-move,
 misc-unused-using-decls,
 modernize-use-default-member-init,
 modernize-use-emplace,
+modernize-use-noexcept,
 modernize-use-nullptr,
 performance-*,
 -performance-avoid-endl,

src/Makefile.am

@@ -1043,6 +1043,7 @@ libbitcoin_util_a_SOURCES = \
   random.cpp \
   randomenv.cpp \
   stacktraces.cpp \
+  streams.cpp \
   support/cleanse.cpp \
   support/lockedpool.cpp \
   sync.cpp \
@@ -1373,6 +1374,7 @@ libdashkernel_la_SOURCES = \
   script/standard.cpp \
   shutdown.cpp \
   spork.cpp \
+  streams.cpp \
   support/cleanse.cpp \
   support/lockedpool.cpp \
   sync.cpp \

src/Makefile.bench.include

@@ -60,7 +60,8 @@ bench_bench_dash_SOURCES = \
   bench/strencodings.cpp \
   bench/string_cast.cpp \
   bench/util_time.cpp \
-  bench/verify_script.cpp
+  bench/verify_script.cpp \
+  bench/xor.cpp
 
 nodist_bench_bench_dash_SOURCES = $(GENERATED_BENCH_FILES)
 

src/bench/bench.h

@@ -14,7 +14,7 @@
 #include <string>
 #include <vector>
 
-#include <bench/nanobench.h>
+#include <bench/nanobench.h> // IWYU pragma: export
 
 /*
  * Usage:

src/bench/xor.cpp

@@ -0,0 +1,24 @@
+// Copyright (c) The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://opensource.org/license/mit/.
+
+#include <bench/bench.h>
+
+#include <random.h>
+#include <streams.h>
+
+#include <cstddef>
+#include <vector>
+
+static void Xor(benchmark::Bench& bench)
+{
+    FastRandomContext frc{/*fDeterministic=*/true};
+    auto data{frc.randbytes<std::byte>(1024)};
+    auto key{frc.randbytes<std::byte>(31)};
+
+    bench.batch(data.size()).unit("byte").run([&] {
+        util::Xor(data, key);
+    });
+}
+
+BENCHMARK(Xor, benchmark::PriorityLevel::HIGH);

src/hash.h

@@ -161,7 +161,6 @@ class CHashWriter : public HashWriter
 
     template<typename T>
     CHashWriter& operator<<(const T& obj) {
-        // Serialize to this stream
         ::Serialize(*this, obj);
         return (*this);
     }
@@ -196,7 +195,6 @@ class CHashVerifier : public CHashWriter
     template<typename T>
     CHashVerifier<Source>& operator>>(T&& obj)
     {
-        // Unserialize from this stream
         ::Unserialize(*this, obj);
         return (*this);
     }

src/streams.cpp

@@ -0,0 +1,66 @@
+// Copyright (c) 2009-present The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://opensource.org/license/mit/.
+
+#include <span.h>
+#include <streams.h>
+
+#include <array>
+
+std::size_t AutoFile::detail_fread(Span<std::byte> dst)
+{
+    if (!m_file) throw std::ios_base::failure("AutoFile::read: file handle is nullptr");
+    if (m_xor.empty()) {
+        return std::fread(dst.data(), 1, dst.size(), m_file);
+    } else {
+        const auto init_pos{std::ftell(m_file)};
+        if (init_pos < 0) throw std::ios_base::failure("AutoFile::read: ftell failed");
+        std::size_t ret{std::fread(dst.data(), 1, dst.size(), m_file)};
+        util::Xor(dst.subspan(0, ret), m_xor, init_pos);
+        return ret;
+    }
+}
+
+void AutoFile::read(Span<std::byte> dst)
+{
+    if (detail_fread(dst) != dst.size()) {
+        throw std::ios_base::failure(feof() ? "AutoFile::read: end of file" : "AutoFile::read: fread failed");
+    }
+}
+
+void AutoFile::ignore(size_t nSize)
+{
+    if (!m_file) throw std::ios_base::failure("AutoFile::ignore: file handle is nullptr");
+    unsigned char data[4096];
+    while (nSize > 0) {
+        size_t nNow = std::min<size_t>(nSize, sizeof(data));
+        if (std::fread(data, 1, nNow, m_file) != nNow) {
+            throw std::ios_base::failure(feof() ? "AutoFile::ignore: end of file" : "AutoFile::ignore: fread failed");
+        }
+        nSize -= nNow;
+    }
+}
+
+void AutoFile::write(Span<const std::byte> src)
+{
+    if (!m_file) throw std::ios_base::failure("AutoFile::write: file handle is nullptr");
+    if (m_xor.empty()) {
+        if (std::fwrite(src.data(), 1, src.size(), m_file) != src.size()) {
+            throw std::ios_base::failure("AutoFile::write: write failed");
+        }
+    } else {
+        auto current_pos{std::ftell(m_file)};
+        if (current_pos < 0) throw std::ios_base::failure("AutoFile::write: ftell failed");
+        std::array<std::byte, 4096> buf;
+        while (src.size() > 0) {
+            auto buf_now{Span{buf}.first(std::min<size_t>(src.size(), buf.size()))};
+            std::copy(src.begin(), src.begin() + buf_now.size(), buf_now.begin());
+            util::Xor(buf_now, m_xor, current_pos);
+            if (std::fwrite(buf_now.data(), 1, buf_now.size(), m_file) != buf_now.size()) {
+                throw std::ios_base::failure{"XorFile::write: failed"};
+            }
+            src = src.subspan(buf_now.size());
+            current_pos += buf_now.size();
+        }
+    }
+}