diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 8f7cf31d7..c3686a651 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,662 +1,663 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 project(bitcoind)
 
 set(CMAKE_CXX_STANDARD 14)
 
 # Default visibility is hidden on all targets.
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 set(CMAKE_CXX_VISIBILITY_PRESET hidden)
 
 option(BUILD_BITCOIN_WALLET "Activate the wallet functionality" ON)
 option(BUILD_BITCOIN_ZMQ "Activate the ZeroMQ functionalities" ON)
 option(BUILD_BITCOIN_CLI "Build bitcoin-cli" ON)
 option(BUILD_BITCOIN_TX "Build bitcoin-tx" ON)
 option(BUILD_BITCOIN_QT "Build bitcoin-qt" ON)
 option(BUILD_BITCOIN_SEEDER "Build bitcoin-seeder" ON)
 option(BUILD_LIBBITCOINCONSENSUS "Build the bitcoinconsenus shared library" ON)
 option(ENABLE_BIP70 "Enable BIP70 (payment protocol) support in GUI" ON)
 option(ENABLE_HARDENING "Harden the executables" ON)
 option(ENABLE_REDUCE_EXPORTS "Reduce the amount of exported symbols" OFF)
 option(ENABLE_STATIC_LIBSTDCXX "Statically link libstdc++" OFF)
 option(ENABLE_GLIBC_BACK_COMPAT "Enable Glibc compatibility features" OFF)
 option(ENABLE_QRCODE "Enable QR code display" ON)
 option(ENABLE_UPNP "Enable UPnP support" ON)
 option(START_WITH_UPNP "Make UPnP the default to map ports" OFF)
 option(ENABLE_CLANG_TIDY "Enable clang-tidy checks for Bitcoin ABC" OFF)
 option(ENABLE_PROFILING "Select the profiling tool to use" OFF)
 option(USE_LD_GOLD "Try to use gold as a linker if available" ON)
 option(USE_JEMALLOC "Use jemalloc as an allocation library" ON)
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
 	set(DEFAULT_ENABLE_DBUS_NOTIFICATIONS ON)
 endif()
 option(ENABLE_DBUS_NOTIFICATIONS "Enable DBus desktop notifications. Linux only." ${DEFAULT_ENABLE_DBUS_NOTIFICATIONS})
 
 # If ccache is available, then use it.
 find_program(CCACHE ccache)
 if(CCACHE)
 	message(STATUS "Using ccache: ${CCACHE}")
 	set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE})
 	set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE})
 endif(CCACHE)
 
 # Disable what we do not need for the native build.
 include(NativeExecutable)
 native_add_cmake_flags(
 	"-DBUILD_BITCOIN_WALLET=OFF"
 	"-DBUILD_BITCOIN_QT=OFF"
 	"-DBUILD_BITCOIN_ZMQ=OFF"
 	"-DENABLE_QRCODE=OFF"
 	"-DENABLE_UPNP=OFF"
 	"-DUSE_JEMALLOC=OFF"
 	# Forward the current setting for clang-tidy
 	"-DENABLE_CLANG_TIDY=${ENABLE_CLANG_TIDY}"
 )
 
 if(ENABLE_CLANG_TIDY)
 	include(ClangTidy)
 endif()
 
 if(ENABLE_SANITIZERS)
 	include(Sanitizers)
 	enable_sanitizers(${ENABLE_SANITIZERS})
 endif()
 
 include(AddCompilerFlags)
 
 if(USE_LD_GOLD)
 	add_linker_flags(-fuse-ld=gold)
 endif()
 
 # Prefer -g3, defaults to -g if unavailable
 foreach(LANGUAGE C CXX)
 	set(COMPILER_DEBUG_LEVEL -g)
 	check_compiler_flags(G3_IS_SUPPORTED ${LANGUAGE} -g3)
 	if(${G3_IS_SUPPORTED})
 		set(COMPILER_DEBUG_LEVEL -g3)
 	endif()
 	add_compile_options_to_configuration_for_language(Debug ${LANGUAGE} ${COMPILER_DEBUG_LEVEL})
 endforeach()
 
 # Define the debugging symbols DEBUG and DEBUG_LOCKORDER when the Debug build
 # type is selected.
 add_compile_definitions_to_configuration(Debug DEBUG DEBUG_LOCKORDER)
 
 # Add -ftrapv when building in Debug
 add_compile_options_to_configuration(Debug -ftrapv)
 
 # All versions of gcc that we commonly use for building are subject to bug
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90348. To work around that, set
 # -fstack-reuse=none for all gcc builds. (Only gcc understands this flag)
 if(NOT ENABLE_CLANG_TIDY)
 	add_compiler_flags(-fstack-reuse=none)
 endif()
 
 # Ensure that WINDRES_PREPROC is enabled when using windres.
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	# Ensure that WINDRES_PREPROC is enabled when using windres.
 	list(APPEND CMAKE_RC_FLAGS "-DWINDRES_PREPROC")
 
 	# Build all static so there is no dll file to distribute.
 	add_linker_flags(-static)
 endif()
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 	add_compile_definitions(MAC_OSX OBJC_OLD_DISPATCH_PROTOTYPES=0)
 	add_linker_flags(-Wl,-dead_strip_dylibs)
 endif()
 
 if(ENABLE_REDUCE_EXPORTS)
 	# Default visibility is set by CMAKE_<LANG>_VISIBILITY_PRESET, but this
 	# doesn't tell if the visibility set is effective.
 	# Check if the flag -fvisibility=hidden is supported, as using the hidden
 	# visibility is a requirement to reduce exports.
 	check_compiler_flags(HAS_CXX_FVISIBILITY CXX -fvisibility=hidden)
 	if(NOT HAS_CXX_FVISIBILITY)
 		message(FATAL_ERROR "Cannot set default symbol visibility. Use -DENABLE_REDUCE_EXPORTS=OFF.")
 	endif()
 
 	# Also hide symbols from static libraries
 	add_linker_flags(-Wl,--exclude-libs,libstdc++)
 endif()
 
 # Enable statically linking libstdc++
 if(ENABLE_STATIC_LIBSTDCXX)
 	add_linker_flags(-static-libstdc++)
 endif()
 
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 if(ENABLE_HARDENING)
 	# Enable stack protection
 	add_cxx_compiler_flags(-fstack-protector-all -Wstack-protector)
 
 	# Enable some buffer overflow checking, except in -O0 builds which
 	# do not support them
 	add_compiler_flags(-U_FORTIFY_SOURCE)
 	add_compile_options($<$<NOT:$<CONFIG:Debug>>:-D_FORTIFY_SOURCE=2>)
 
 	# Enable ASLR (these flags are primarily targeting MinGw)
 	add_linker_flags(-Wl,--dynamicbase -Wl,--nxcompat -Wl,--high-entropy-va)
 
 	# Make the relocated sections read-only
 	add_linker_flags(-Wl,-z,relro -Wl,-z,now)
 
 	# CMake provides the POSITION_INDEPENDENT_CODE property to set PIC/PIE.
 	# Unfortunately setting the -pie linker flag this way require CMake >= 3.14,
 	# which is not widely distributed at the time of writing.
 	# FIXME: remove the fallback case when cmake >= 3.14 get enforced.
 	if(POLICY CMP0083)
 		cmake_policy(SET CMP0083 NEW)
 		include(CheckPIESupported)
 		check_pie_supported()
 	elseif(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		check_linker_flag(PIE_IS_SUPPORTED -pie)
 		if(${PIE_IS_SUPPORTED})
 			add_link_options($<$<STREQUAL:$<TARGET_PROPERTY:TYPE>,EXECUTABLE>:-pie>)
 		endif()
 	endif()
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		# MinGw provides its own libssp for stack smashing protection
 		link_libraries(ssp)
 	endif()
 endif()
 
 if(ENABLE_PROFILING MATCHES "gprof")
 	message(STATUS "Enable profiling with gprof")
 
 	# -pg is incompatible with -pie. Since hardening and profiling together
 	# doesn't make sense, we simply make them mutually exclusive here.
 	# Additionally, hardened toolchains may force -pie by default, in which
 	# case it needs to be turned off with -no-pie.
 	if(ENABLE_HARDENING)
 		message(FATAL_ERROR "Profiling with gprof requires disabling hardening with -DENABLE_HARDENING=OFF.")
 	endif()
 	add_linker_flags(-no-pie)
 
 	add_compiler_flags(-pg)
 	add_linker_flags(-pg)
 endif()
 
 # Enable warning
 add_c_compiler_flags(-Wnested-externs -Wstrict-prototypes)
 add_compiler_flags(
 	-Wall
 	-Wextra
 	-Wformat
 	-Wvla
 	-Wcast-align
 	-Wunused-parameter
 	-Wmissing-braces
 	-Wthread-safety-analysis
 	-Wshadow
 	-Wrange-loop-analysis
 	-Wredundant-decls
 )
 add_compiler_flag_group(-Wformat -Wformat-security)
 add_cxx_compiler_flags(
 	-Wredundant-move
 )
 
 option(EXTRA_WARNINGS "Enable extra warnings" OFF)
 if(EXTRA_WARNINGS)
 	add_cxx_compiler_flags(-Wsuggest-override)
 else()
 	add_compiler_flags(-Wno-unused-parameter)
 	add_compiler_flags(-Wno-implicit-fallthrough)
 endif()
 
 # libtool style configure
 add_subdirectory(config)
 
 # Enable LFS (Large File Support) on targets that don't have it natively.
 # This should be defined before the libraries are included as leveldb need the
 # definition to be set.
 if(NOT HAVE_LARGE_FILE_SUPPORT)
 	add_compile_definitions(_FILE_OFFSET_BITS=64)
 	add_linker_flags(-Wl,--large-address-aware)
 endif()
 
 if(ENABLE_GLIBC_BACK_COMPAT)
 	# Wrap some glibc functions with ours
 	add_linker_flags(-Wl,--wrap=__divmoddi4)
 	add_linker_flags(-Wl,--wrap=log2f)
 
 	if(NOT HAVE_LARGE_FILE_SUPPORT)
 		add_linker_flags(-Wl,--wrap=fcntl -Wl,--wrap=fcntl64)
 	endif()
 endif()
 
 if(USE_JEMALLOC)
 	# Most of the sanitizers require their instrumented allocation functions to
 	# be fully functional. This is obviously the case for all the memory related
 	# sanitizers (asan, lsan, msan) but not only.
 	if(ENABLE_SANITIZERS)
 		message(WARNING "Jemalloc is incompatible with the sanitizers and has been disabled.")
 	else()
 		find_package(Jemalloc 3.6.0 REQUIRED)
 		link_libraries(Jemalloc::jemalloc)
 	endif()
 endif()
 
 
 # Make sure that all the global compiler and linker flags are set BEFORE
 # including the libraries so they apply as needed.
 
 
 # libraries
 add_subdirectory(crypto)
 add_subdirectory(leveldb)
 add_subdirectory(secp256k1)
 add_subdirectory(univalue)
 
 # Find the git root, and returns the full path to the .git/logs/HEAD file if
 # it exists.
 function(find_git_head_logs_file RESULT)
 	find_package(Git)
 	if(GIT_FOUND)
 		execute_process(
 			COMMAND "${GIT_EXECUTABLE}" "rev-parse" "--show-toplevel"
 			WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
 			OUTPUT_VARIABLE GIT_ROOT
 			RESULT_VARIABLE GIT_RESULT
 			OUTPUT_STRIP_TRAILING_WHITESPACE
 			ERROR_QUIET
 		)
 
 		if(GIT_RESULT EQUAL 0)
 			set(GIT_LOGS_DIR "${GIT_ROOT}/.git/logs")
 			set(GIT_HEAD_LOGS_FILE "${GIT_LOGS_DIR}/HEAD")
 			# If the .git/logs/HEAD does not exist, create it
 			if(NOT EXISTS "${GIT_HEAD_LOGS_FILE}")
 				file(MAKE_DIRECTORY "${GIT_LOGS_DIR}")
 				file(TOUCH "${GIT_HEAD_LOGS_FILE}")
 			endif()
 			set(${RESULT} "${GIT_HEAD_LOGS_FILE}" PARENT_SCOPE)
 		endif()
 	endif()
 endfunction()
 
 find_git_head_logs_file(GIT_HEAD_LOGS_FILE)
 
 set(OBJ_DIR "${CMAKE_CURRENT_BINARY_DIR}/obj")
 file(MAKE_DIRECTORY "${OBJ_DIR}")
 set(BUILD_HEADER "${OBJ_DIR}/build.h")
 set(BUILD_HEADER_TMP "${BUILD_HEADER}.tmp")
 
 add_custom_command(
 	DEPENDS
 		"${GIT_HEAD_LOGS_FILE}"
 		"${CMAKE_SOURCE_DIR}/share/genbuild.sh"
 	OUTPUT
 		"${BUILD_HEADER}"
 	COMMAND
 		"${CMAKE_SOURCE_DIR}/share/genbuild.sh"
 		"${BUILD_HEADER_TMP}"
 		"${CMAKE_SOURCE_DIR}"
 	COMMAND
 		${CMAKE_COMMAND} -E copy_if_different "${BUILD_HEADER_TMP}" "${BUILD_HEADER}"
 	COMMAND
 		${CMAKE_COMMAND} -E remove "${BUILD_HEADER_TMP}"
 )
 
 # Because the Bitcoin ABc source code is disorganised, we
 # end up with a bunch of libraries without any apparent
 # cohesive structure. This is inherited from Bitcoin Core
 # and reflecting this.
 # TODO: Improve the structure once cmake is rocking.
 
 # Various completely unrelated features shared by all executables.
 add_library(util
 	chainparamsbase.cpp
 	clientversion.cpp
 	compat/glibcxx_sanity.cpp
 	compat/strnlen.cpp
 	fs.cpp
 	interfaces/handler.cpp
 	logging.cpp
 	random.cpp
 	randomenv.cpp
 	rcu.cpp
 	rpc/protocol.cpp
 	support/cleanse.cpp
 	support/lockedpool.cpp
 	sync.cpp
 	threadinterrupt.cpp
 	uint256.cpp
 	util/bip32.cpp
 	util/bytevectorhash.cpp
 	util/error.cpp
 	util/moneystr.cpp
 	util/settings.cpp
 	util/strencodings.cpp
+	util/string.cpp
 	util/system.cpp
 	util/threadnames.cpp
 	util/time.cpp
 	util/url.cpp
 	util/validation.cpp
 
 	# obj/build.h
 	"${BUILD_HEADER}"
 )
 
 target_compile_definitions(util PUBLIC HAVE_CONFIG_H HAVE_BUILD_INFO)
 target_include_directories(util
 	PUBLIC
 		.
 		# To access the config/ and obj/ directories
 		${CMAKE_CURRENT_BINARY_DIR}
 )
 
 if(ENABLE_GLIBC_BACK_COMPAT)
 	target_sources(util PRIVATE compat/glibc_compat.cpp)
 endif()
 
 # Target specific configs
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	set(Boost_USE_STATIC_LIBS ON)
 	set(Boost_USE_STATIC_RUNTIME ON)
 	set(Boost_THREADAPI win32)
 
 	find_package(SHLWAPI REQUIRED)
 	# We cannot use the imported target here, because cmake will introduce an
 	# -isystem compilation directive and cause the build to fail with MinGw.
 	# This comes from a couple cmake bugs:
 	#  - https://gitlab.kitware.com/cmake/cmake/issues/16291
 	#  - https://gitlab.kitware.com/cmake/cmake/issues/19095
 	# These issues are solved from cmake 3.14.1. Once this version is enforced,
 	# the following can be used:
 	# target_link_libraries(util SHLWAPI::shlwapi)
 	target_link_libraries(util ${SHLWAPI_LIBRARIES})
 	target_include_directories(util PUBLIC ${SHLWAPI_INCLUDE_DIRS})
 
 	find_library(WS2_32_LIBRARY NAMES ws2_32)
 	target_link_libraries(util ${WS2_32_LIBRARY})
 
 	target_compile_definitions(util PUBLIC BOOST_THREAD_USE_LIB)
 endif()
 
 # Boost packages
 set(BOOST_PACKAGES_REQUIRED chrono filesystem thread)
 
 function(prepend var prefix)
 	set(listVar "")
 	foreach(f ${ARGN})
 		list(APPEND listVar "${prefix}${f}")
 	endforeach(f)
 	set(${var} "${listVar}" PARENT_SCOPE)
 endfunction(prepend)
 
 prepend(BOOST_LIBRARIES "Boost::" ${BOOST_PACKAGES_REQUIRED})
 
 find_package(Boost 1.58 REQUIRED ${BOOST_PACKAGES_REQUIRED})
 
 # This require libevent
 set(EVENT_MIN_VERSION 2.0.22)
 find_package(Event ${EVENT_MIN_VERSION} REQUIRED COMPONENTS event)
 
 target_link_libraries(util univalue crypto Event::event ${BOOST_LIBRARIES})
 
 # Make sure boost uses std::atomic (it doesn't before 1.63)
 target_compile_definitions(util PUBLIC BOOST_SP_USE_STD_ATOMIC BOOST_AC_USE_STD_ATOMIC)
 
 # More completely unrelated features shared by all executables.
 # Because nothing says this is different from util than "common"
 add_library(common
 	amount.cpp
 	base58.cpp
 	bloom.cpp
 	cashaddr.cpp
 	cashaddrenc.cpp
 	chainparams.cpp
 	config.cpp
 	consensus/merkle.cpp
 	coins.cpp
 	compressor.cpp
 	eventloop.cpp
 	feerate.cpp
 	core_read.cpp
 	core_write.cpp
 	key.cpp
 	key_io.cpp
 	keystore.cpp
 	merkleblock.cpp
 	net_permissions.cpp
 	netaddress.cpp
 	netbase.cpp
 	outputtype.cpp
 	policy/policy.cpp
 	primitives/block.cpp
 	protocol.cpp
 	psbt.cpp
 	rpc/rawtransaction_util.cpp
 	rpc/util.cpp
 	scheduler.cpp
 	versionbitsinfo.cpp
 	warnings.cpp
 )
 
 target_link_libraries(common util secp256k1)
 
 # script library
 add_library(script
 	script/bitfield.cpp
 	script/descriptor.cpp
 	script/interpreter.cpp
 	script/ismine.cpp
 	script/script.cpp
 	script/script_error.cpp
 	script/sigencoding.cpp
 	script/sign.cpp
 	script/standard.cpp
 )
 
 target_link_libraries(script common)
 
 # libbitcoinconsensus
 add_library(bitcoinconsensus
 	arith_uint256.cpp
 	hash.cpp
 	primitives/transaction.cpp
 	pubkey.cpp
 	uint256.cpp
 	util/strencodings.cpp
 )
 
 target_link_libraries(bitcoinconsensus script)
 
 include(InstallationHelper)
 if(BUILD_LIBBITCOINCONSENSUS)
 	target_compile_definitions(bitcoinconsensus
 		PUBLIC
 			BUILD_BITCOIN_INTERNAL
 			HAVE_CONSENSUS_LIB
 	)
 
 	install_shared_library(bitcoinconsensus
 		script/bitcoinconsensus.cpp
 		PUBLIC_HEADER script/bitcoinconsensus.h
 	)
 endif()
 
 # Bitcoin server facilities
 add_library(server
 	addrdb.cpp
 	addrman.cpp
 	avalanche.cpp
 	banman.cpp
 	blockencodings.cpp
 	blockfilter.cpp
 	chain.cpp
 	checkpoints.cpp
 	config.cpp
 	consensus/activation.cpp
 	consensus/tx_verify.cpp
 	consensus/tx_check.cpp
 	dbwrapper.cpp
 	flatfile.cpp
 	httprpc.cpp
 	httpserver.cpp
 	index/base.cpp
 	index/blockfilterindex.cpp
 	index/txindex.cpp
 	init.cpp
 	interfaces/chain.cpp
 	interfaces/node.cpp
 	miner.cpp
 	minerfund.cpp
 	net.cpp
 	net_processing.cpp
 	node/coin.cpp
 	node/coinstats.cpp
 	node/psbt.cpp
 	node/transaction.cpp
 	noui.cpp
 	policy/fees.cpp
 	policy/mempool.cpp
 	policy/settings.cpp
 	pow.cpp
 	rest.cpp
 	rpc/abc.cpp
 	rpc/avalanche.cpp
 	rpc/blockchain.cpp
 	rpc/command.cpp
 	rpc/jsonrpcrequest.cpp
 	rpc/mining.cpp
 	rpc/misc.cpp
 	rpc/net.cpp
 	rpc/rawtransaction.cpp
 	rpc/server.cpp
 	script/scriptcache.cpp
 	script/sigcache.cpp
 	shutdown.cpp
 	timedata.cpp
 	torcontrol.cpp
 	txdb.cpp
 	txmempool.cpp
 	ui_interface.cpp
 	validation.cpp
 	validationinterface.cpp
 	versionbits.cpp
 )
 
 target_include_directories(server PRIVATE leveldb/helpers/memenv)
 
 target_link_libraries(server
 	Event::event
 	bitcoinconsensus
 	leveldb
 	memenv
 )
 
 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	find_package(Event ${EVENT_MIN_VERSION} REQUIRED COMPONENTS pthreads)
 	target_link_libraries(server Event::pthreads)
 endif()
 
 if(ENABLE_UPNP)
 	find_package(MiniUPnPc 1.5 REQUIRED)
 	target_link_libraries(server MiniUPnPc::miniupnpc)
 
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		# TODO: check if we are really using a static library. Assume this is
 		# the one from the depends for now since the native windows build is not
 		# supported.
 		target_compile_definitions(server
 			PUBLIC -DSTATICLIB
 			PUBLIC -DMINIUPNP_STATICLIB
 		)
 	endif()
 endif()
 
 # Test suite.
 add_subdirectory(test)
 
 # Benchmark suite.
 add_subdirectory(bench)
 
 include(BinaryTest)
 
 # Wallet
 if(BUILD_BITCOIN_WALLET)
 	add_subdirectory(wallet)
 	target_link_libraries(server wallet)
 
 	# bitcoin-wallet
 	add_executable(bitcoin-wallet bitcoin-wallet.cpp)
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		target_sources(bitcoin-wallet PRIVATE bitcoin-wallet-res.rc)
 	endif()
 
 	target_link_libraries(bitcoin-wallet wallet-tool common util)
 
 	add_to_symbols_check(bitcoin-wallet)
 	add_to_security_check(bitcoin-wallet)
 
 	install_target(bitcoin-wallet)
 else()
 	target_sources(server PRIVATE dummywallet.cpp)
 endif()
 
 # ZeroMQ
 if(BUILD_BITCOIN_ZMQ)
 	add_subdirectory(zmq)
 	target_link_libraries(server zmq)
 endif()
 
 # RPC client support
 add_library(rpcclient rpc/client.cpp)
 target_link_libraries(rpcclient univalue util)
 
 # bitcoin-seeder
 if(BUILD_BITCOIN_SEEDER)
 	add_subdirectory(seeder)
 endif()
 
 # bitcoin-cli
 if(BUILD_BITCOIN_CLI)
 	add_executable(bitcoin-cli bitcoin-cli.cpp)
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		target_sources(bitcoin-cli PRIVATE bitcoin-cli-res.rc)
 	endif()
 
 	target_link_libraries(bitcoin-cli common rpcclient Event::event)
 
 	add_to_symbols_check(bitcoin-cli)
 	add_to_security_check(bitcoin-cli)
 
 	install_target(bitcoin-cli)
 endif()
 
 # bitcoin-tx
 if(BUILD_BITCOIN_TX)
 	add_executable(bitcoin-tx bitcoin-tx.cpp)
 	if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 		target_sources(bitcoin-tx PRIVATE bitcoin-tx-res.rc)
 	endif()
 
 	target_link_libraries(bitcoin-tx bitcoinconsensus)
 
 	add_to_symbols_check(bitcoin-tx)
 	add_to_security_check(bitcoin-tx)
 
 	install_target(bitcoin-tx)
 endif()
 
 # bitcoind
 add_executable(bitcoind bitcoind.cpp)
 target_link_libraries(bitcoind server)
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	target_sources(bitcoind PRIVATE bitcoind-res.rc)
 endif()
 add_to_symbols_check(bitcoind)
 add_to_security_check(bitcoind)
 
 install_target(bitcoind)
 
 # Bitcoin-qt
 if(BUILD_BITCOIN_QT)
 	add_subdirectory(qt)
 endif()
diff --git a/src/Makefile.am b/src/Makefile.am
index 92b211d92..807760aa8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,805 +1,807 @@
 # Copyright (c) 2013-2016 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 DIST_SUBDIRS = secp256k1 univalue
 
 AM_LDFLAGS = $(PTHREAD_CFLAGS) $(LIBTOOL_LDFLAGS) $(HARDENED_LDFLAGS) $(GPROF_LDFLAGS) $(SANITIZER_LDFLAGS)
 AM_CXXFLAGS = $(DEBUG_CXXFLAGS) $(HARDENED_CXXFLAGS) $(WARN_CXXFLAGS) $(NOWARN_CXXFLAGS) $(ERROR_CXXFLAGS) $(GPROF_CXXFLAGS) $(SANITIZER_CXXFLAGS)
 AM_CPPFLAGS = $(DEBUG_CPPFLAGS) $(HARDENED_CPPFLAGS)
 AM_LIBTOOLFLAGS = --preserve-dup-deps
 EXTRA_LIBRARIES =
 
 if EMBEDDED_UNIVALUE
 LIBUNIVALUE = univalue/libunivalue.la
 
 $(LIBUNIVALUE): $(wildcard univalue/lib/*) $(wildcard univalue/include/*)
 	$(AM_V_at)$(MAKE) $(AM_MAKEFLAGS) -C $(@D) $(@F)
 else
 LIBUNIVALUE = $(UNIVALUE_LIBS)
 endif
 
 BITCOIN_INCLUDES=-I$(builddir) $(BDB_CPPFLAGS) $(BOOST_CPPFLAGS) $(LEVELDB_CPPFLAGS)
 
 BITCOIN_INCLUDES += -I$(srcdir)/secp256k1/include
 BITCOIN_INCLUDES += $(UNIVALUE_CFLAGS)
 
 BITCOIN_SEEDER_INCLUDES = -I$(srcdir)/seeder
 BITCOIN_SEEDER_INCLUDES += $(BITCOIN_INCLUDES)
 
 LIBBITCOIN_SERVER=libbitcoin_server.a
 LIBBITCOIN_COMMON=libbitcoin_common.a
 LIBBITCOIN_CONSENSUS=libbitcoin_consensus.a
 LIBBITCOIN_CLI=libbitcoin_cli.a
 LIBBITCOIN_UTIL=libbitcoin_util.a
 LIBBITCOIN_CRYPTO_BASE=crypto/libbitcoin_crypto_base.a
 LIBBITCOINQT=qt/libbitcoinqt.a
 LIBSECP256K1=secp256k1/libsecp256k1.la
 
 if ENABLE_ZMQ
 LIBBITCOIN_ZMQ=libbitcoin_zmq.a
 endif
 if BUILD_BITCOIN_LIBS
 LIBBITCOINCONSENSUS=libbitcoinconsensus.la
 endif
 if BUILD_BITCOIN_SEEDER
 LIBBITCOIN_SEEDER=libbitcoin_seeder.a
 endif
 if ENABLE_WALLET
 LIBBITCOIN_WALLET=libbitcoin_wallet.a
 LIBBITCOIN_WALLET_TOOL=libbitcoin_wallet_tool.a
 endif
 
 LIBBITCOIN_CRYPTO= $(LIBBITCOIN_CRYPTO_BASE)
 if ENABLE_SSE41
 LIBBITCOIN_CRYPTO_SSE41 = crypto/libbitcoin_crypto_sse41.a
 LIBBITCOIN_CRYPTO += $(LIBBITCOIN_CRYPTO_SSE41)
 endif
 if ENABLE_AVX2
 LIBBITCOIN_CRYPTO_AVX2 = crypto/libbitcoin_crypto_avx2.a
 LIBBITCOIN_CRYPTO += $(LIBBITCOIN_CRYPTO_AVX2)
 endif
 if ENABLE_SHANI
 LIBBITCOIN_CRYPTO_SHANI = crypto/libbitcoin_crypto_shani.a
 LIBBITCOIN_CRYPTO += $(LIBBITCOIN_CRYPTO_SHANI)
 endif
 
 $(LIBSECP256K1): $(wildcard secp256k1/src/*) $(wildcard secp256k1/include/*)
 	$(AM_V_at)$(MAKE) $(AM_MAKEFLAGS) -C $(@D) $(@F)
 
 # Make is not made aware of per-object dependencies to avoid limiting building parallelization
 # But to build the less dependent modules first, we manually select their order here:
 EXTRA_LIBRARIES += \
   $(LIBBITCOIN_CRYPTO) \
   $(LIBBITCOIN_UTIL) \
   $(LIBBITCOIN_COMMON) \
   $(LIBBITCOIN_CONSENSUS) \
   $(LIBBITCOIN_SERVER) \
   $(LIBBITCOIN_CLI) \
   $(LIBBITCOIN_SEEDER) \
   $(LIBBITCOIN_WALLET) \
   $(LIBBITCOIN_WALLET_TOOL) \
   $(LIBBITCOIN_ZMQ)
 
 lib_LTLIBRARIES = $(LIBBITCOINCONSENSUS)
 
 bin_PROGRAMS =
 noinst_PROGRAMS =
 TESTS =
 BENCHMARKS =
 
 if BUILD_BITCOIND
   bin_PROGRAMS += bitcoind
 endif
 
 if BUILD_BITCOIN_SEEDER
   bin_PROGRAMS += bitcoin-seeder
 endif
 
 if BUILD_BITCOIN_CLI
   bin_PROGRAMS += bitcoin-cli
 endif
 if BUILD_BITCOIN_TX
   bin_PROGRAMS += bitcoin-tx
 endif
 if ENABLE_WALLET
 if BUILD_BITCOIN_WALLET
   bin_PROGRAMS += bitcoin-wallet
 endif
 endif
 
 .PHONY: FORCE check-symbols check-security
 # bitcoin core #
 BITCOIN_CORE_H = \
   addrdb.h \
   addrman.h \
   attributes.h \
   avalanche.h \
   banman.h \
   base58.h \
   bloom.h \
   blockencodings.h \
   blockfileinfo.h \
   blockfilter.h \
   blockindexworkcomparator.h \
   blockstatus.h \
   blockvalidity.h \
   cashaddr.h \
   cashaddrenc.h \
   chain.h \
   chainparams.h \
   chainparamsbase.h \
   chainparamsconstants.h \
   chainparamsseeds.h \
   checkpoints.h \
   checkqueue.h \
   clientversion.h \
   coins.h \
   compat.h \
   compat/assumptions.h \
   compat/byteswap.h \
   compat/cpuid.h \
   compat/endian.h \
   compat/sanity.h \
   compat/setenv.h \
   compressor.h \
   config.h \
   consensus/activation.h \
   consensus/consensus.h \
   consensus/tx_check.h \
   consensus/tx_verify.h \
   core_io.h \
   core_memusage.h \
   cuckoocache.h \
   disconnectresult.h \
   eventloop.h \
   flatfile.h \
   fs.h \
   httprpc.h \
   httpserver.h \
   index/base.h \
   index/blockfilterindex.h \
   index/txindex.h \
   indirectmap.h \
   init.h \
   interfaces/chain.h \
   interfaces/handler.h \
   interfaces/node.h \
   interfaces/wallet.h \
   key.h \
   key_io.h \
   keystore.h \
   dbwrapper.h \
   limitedmap.h \
   logging.h \
   memusage.h \
   merkleblock.h \
   miner.h \
   minerfund.h \
   net.h \
   net_permissions.h \
   net_processing.h \
   netaddress.h \
   netbase.h \
   netmessagemaker.h \
   node/coin.h \
   node/context.h \
   node/coinstats.h \
   node/psbt.h \
   node/transaction.h \
   noui.h \
   optional.h \
   outputtype.h \
   policy/fees.h \
   policy/mempool.h \
   policy/policy.h \
   policy/settings.h \
   pow.h \
   protocol.h \
   psbt.h \
   radix.h \
   random.h \
   randomenv.h \
   rcu.h \
   reverse_iterator.h \
   reverselock.h \
   rpc/blockchain.h \
   rpc/client.h \
   rpc/command.h \
   rpc/jsonrpcrequest.h \
   rpc/mining.h \
   rpc/protocol.h \
   rpc/rawtransaction_util.h \
   rpc/server.h \
   rpc/register.h \
   rpc/util.h \
   rwcollection.h \
   scheduler.h \
   script/descriptor.h \
   script/ismine.h \
   script/scriptcache.h \
   script/sigcache.h \
   script/sign.h \
   script/standard.h \
   shutdown.h \
   streams.h \
   support/allocators/secure.h \
   support/allocators/zeroafterfree.h \
   support/cleanse.h \
   support/events.h \
   support/lockedpool.h \
   sync.h \
   threadsafety.h \
   threadinterrupt.h \
   timedata.h \
   torcontrol.h \
   txdb.h \
   txmempool.h \
   ui_interface.h \
   undo.h \
   util/bitmanip.h \
   util/bip32.h \
   util/bytevectorhash.h \
   util/check.h \
   util/error.h \
   util/macros.h \
   util/moneystr.h \
   util/system.h \
   util/settings.h \
+  util/string.h \
   util/threadnames.h \
   util/time.h \
   util/translation.h \
   util/url.h \
   util/validation.h \
   validation.h \
   validationinterface.h \
   versionbits.h \
   versionbitsinfo.h \
   walletinitinterface.h \
   wallet/coincontrol.h \
   wallet/coinselection.h \
   wallet/crypter.h \
   wallet/db.h \
   wallet/rpcdump.h \
   wallet/fees.h \
   wallet/load.h \
   wallet/psbtwallet.h \
   wallet/rpcwallet.h \
   wallet/wallet.h \
   wallet/walletdb.h \
   wallet/wallettool.h \
   wallet/walletutil.h \
   warnings.h \
   zmq/zmqabstractnotifier.h \
   zmq/zmqconfig.h\
   zmq/zmqnotificationinterface.h \
   zmq/zmqpublishnotifier.h \
   zmq/zmqrpc.h
 
 
 obj/build.h: FORCE
 	@$(MKDIR_P) "$(builddir)/obj"
 	@$(top_srcdir)/share/genbuild.sh "$(abs_top_builddir)/src/obj/build.h" \
 	  "$(abs_top_srcdir)"
 libbitcoin_util_a-clientversion.$(OBJEXT): obj/build.h
 
 # server: shared between bitcoind and bitcoin-qt
 # Contains code accessing mempool and chain state that is meant to be separated
 # from wallet and gui code (see node/README.md). Shared code should go in
 # libbitcoin_common or libbitcoin_util libraries, instead.
 libbitcoin_server_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(MINIUPNPC_CPPFLAGS) $(EVENT_CFLAGS) $(EVENT_PTHREADS_CFLAGS)
 libbitcoin_server_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_server_a_SOURCES = \
   addrdb.cpp \
   addrman.cpp \
   avalanche.cpp \
   banman.cpp \
   blockencodings.cpp \
   blockfilter.cpp \
   chain.cpp \
   checkpoints.cpp \
   config.cpp \
   consensus/activation.cpp \
   consensus/tx_verify.cpp \
   flatfile.cpp \
   httprpc.cpp \
   httpserver.cpp \
   index/base.cpp \
   index/blockfilterindex.cpp \
   index/txindex.cpp \
   init.cpp \
   interfaces/chain.cpp \
   interfaces/node.cpp \
   dbwrapper.cpp \
   miner.cpp \
   minerfund.cpp \
   net.cpp \
   net_processing.cpp \
   node/coin.cpp \
   node/coinstats.cpp \
   node/psbt.cpp \
   node/transaction.cpp \
   noui.cpp \
   policy/fees.cpp \
   policy/mempool.cpp \
   policy/settings.cpp \
   pow.cpp \
   rest.cpp \
   rpc/abc.cpp \
   rpc/avalanche.cpp \
   rpc/blockchain.cpp \
   rpc/command.cpp \
   rpc/jsonrpcrequest.cpp \
   rpc/mining.cpp \
   rpc/misc.cpp \
   rpc/net.cpp \
   rpc/rawtransaction.cpp \
   rpc/server.cpp \
   script/scriptcache.cpp \
   script/sigcache.cpp \
   shutdown.cpp \
   timedata.cpp \
   torcontrol.cpp \
   txdb.cpp \
   txmempool.cpp \
   ui_interface.cpp \
   validation.cpp \
   validationinterface.cpp \
   versionbits.cpp \
   $(BITCOIN_CORE_H)
 
 if ENABLE_WALLET
 libbitcoin_server_a_SOURCES += wallet/init.cpp
 endif
 if !ENABLE_WALLET
 libbitcoin_server_a_SOURCES += dummywallet.cpp
 endif
 
 if ENABLE_ZMQ
 libbitcoin_zmq_a_CPPFLAGS = $(BITCOIN_INCLUDES) $(ZMQ_CFLAGS)
 libbitcoin_zmq_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_zmq_a_SOURCES = \
   zmq/zmqabstractnotifier.cpp \
   zmq/zmqnotificationinterface.cpp \
   zmq/zmqpublishnotifier.cpp \
   zmq/zmqrpc.cpp
 endif
 
 
 # wallet: shared between bitcoind and bitcoin-qt, but only linked
 # when wallet enabled
 libbitcoin_wallet_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_wallet_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_wallet_a_SOURCES = \
   interfaces/wallet.cpp \
   wallet/coincontrol.cpp \
   wallet/crypter.cpp \
   wallet/coinselection.cpp \
   wallet/db.cpp \
   wallet/fees.cpp \
   wallet/load.cpp \
   wallet/psbtwallet.cpp \
   wallet/rpcdump.cpp \
   wallet/rpcwallet.cpp \
   wallet/wallet.cpp \
   wallet/walletdb.cpp \
   wallet/walletutil.cpp \
   $(BITCOIN_CORE_H)
 
 libbitcoin_wallet_tool_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_wallet_tool_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_wallet_tool_a_SOURCES = \
   wallet/wallettool.cpp \
   $(BITCOIN_CORE_H)
 
 # crypto primitives library
 crypto_libbitcoin_crypto_base_a_CPPFLAGS = $(AM_CPPFLAGS)
 crypto_libbitcoin_crypto_base_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 crypto_libbitcoin_crypto_base_a_SOURCES = \
   crypto/aes.cpp \
   crypto/aes.h \
   crypto/chacha20.h \
   crypto/chacha20.cpp \
   crypto/common.h \
   crypto/hmac_sha256.cpp \
   crypto/hmac_sha256.h \
   crypto/hmac_sha512.cpp \
   crypto/hmac_sha512.h \
   crypto/ripemd160.cpp \
   crypto/ripemd160.h \
   crypto/sha1.cpp \
   crypto/sha1.h \
   crypto/sha256.cpp \
   crypto/sha256.h \
   crypto/sha512.cpp \
   crypto/sha512.h \
   crypto/siphash.cpp \
   crypto/siphash.h
 
 if USE_ASM
 crypto_libbitcoin_crypto_base_a_SOURCES += crypto/sha256_sse4.cpp
 endif
 
 crypto_libbitcoin_crypto_sse41_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 crypto_libbitcoin_crypto_sse41_a_CPPFLAGS = $(AM_CPPFLAGS)
 crypto_libbitcoin_crypto_sse41_a_CXXFLAGS += $(SSE41_CXXFLAGS)
 crypto_libbitcoin_crypto_sse41_a_CPPFLAGS += -DENABLE_SSE41
 crypto_libbitcoin_crypto_sse41_a_SOURCES = crypto/sha256_sse41.cpp
 
 crypto_libbitcoin_crypto_avx2_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 crypto_libbitcoin_crypto_avx2_a_CPPFLAGS = $(AM_CPPFLAGS)
 crypto_libbitcoin_crypto_avx2_a_CXXFLAGS += $(AVX2_CXXFLAGS)
 crypto_libbitcoin_crypto_avx2_a_CPPFLAGS += -DENABLE_AVX2
 crypto_libbitcoin_crypto_avx2_a_SOURCES = crypto/sha256_avx2.cpp
 
 crypto_libbitcoin_crypto_shani_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 crypto_libbitcoin_crypto_shani_a_CPPFLAGS = $(AM_CPPFLAGS)
 crypto_libbitcoin_crypto_shani_a_CXXFLAGS += $(SHANI_CXXFLAGS)
 crypto_libbitcoin_crypto_shani_a_CPPFLAGS += -DENABLE_SHANI
 crypto_libbitcoin_crypto_shani_a_SOURCES = crypto/sha256_shani.cpp
 
 # consensus: shared between all executables that validate any consensus rules.
 libbitcoin_consensus_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_consensus_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_consensus_a_SOURCES = \
   amount.h \
   arith_uint256.cpp \
   arith_uint256.h \
   consensus/merkle.cpp \
   consensus/merkle.h \
   consensus/params.h \
   consensus/tx_check.cpp \
   consensus/validation.h \
   feerate.h \
   hash.cpp \
   hash.h \
   prevector.h \
   primitives/block.cpp \
   primitives/block.h \
   primitives/transaction.cpp \
   primitives/transaction.h \
   primitives/txid.h \
   pubkey.cpp \
   pubkey.h \
   script/bitcoinconsensus.cpp \
   script/bitfield.cpp \
   script/bitfield.h \
   script/sighashtype.h \
   script/interpreter.cpp \
   script/interpreter.h \
   script/script.cpp \
   script/script.h \
   script/script_error.cpp \
   script/script_error.h \
   script/script_flags.h \
   script/script_metrics.h \
   script/sigencoding.cpp \
   script/sigencoding.h \
   serialize.h \
   span.h \
   tinyformat.h \
   uint256.cpp \
   uint256.h \
   util/strencodings.cpp \
   util/strencodings.h \
   version.h
 
 # common: shared between bitcoind, and bitcoin-qt and non-server tools
 libbitcoin_common_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_common_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_common_a_SOURCES = \
   amount.cpp \
   base58.cpp \
   cashaddr.cpp \
   cashaddrenc.cpp \
   bloom.cpp \
   chainparams.cpp \
   config.cpp \
   coins.cpp \
   compressor.cpp \
   eventloop.cpp \
   feerate.cpp \
   core_read.cpp \
   core_write.cpp \
   key.cpp \
   key_io.cpp \
   keystore.cpp \
   merkleblock.cpp \
   net_permissions.cpp \
   netaddress.cpp \
   netbase.cpp \
   outputtype.cpp \
   policy/policy.cpp \
   protocol.cpp \
   psbt.cpp \
   rpc/rawtransaction_util.cpp \
   rpc/util.cpp \
   scheduler.cpp \
   script/descriptor.cpp \
   script/ismine.cpp \
   script/sign.cpp \
   script/standard.cpp \
   versionbitsinfo.cpp \
   warnings.cpp \
   $(BITCOIN_CORE_H)
 
 # util: shared between all executables.
 # This library *must* be included to make sure that the glibc
 # backward-compatibility objects and their sanity checks are linked.
 libbitcoin_util_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_util_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_util_a_SOURCES = \
   support/lockedpool.cpp \
   chainparamsbase.cpp \
   clientversion.cpp \
   compat/glibcxx_sanity.cpp \
   compat/strnlen.cpp \
   fs.cpp \
   interfaces/handler.cpp \
   logging.cpp \
   random.cpp \
   randomenv.cpp \
   rcu.cpp \
   rpc/protocol.cpp \
   support/cleanse.cpp \
   sync.cpp \
   threadinterrupt.cpp \
   uint256.cpp \
   uint256.h \
   util/error.cpp \
   util/bip32.cpp \
   util/system.cpp \
   util/moneystr.cpp \
   util/settings.cpp \
   util/strencodings.cpp \
+  util/string.cpp \
   util/threadnames.cpp \
   util/time.cpp \
   util/url.cpp \
   util/validation.cpp \
   util/bytevectorhash.cpp \
   $(BITCOIN_CORE_H)
 
 if GLIBC_BACK_COMPAT
 libbitcoin_util_a_SOURCES += compat/glibc_compat.cpp
 AM_LDFLAGS += $(COMPAT_LDFLAGS)
 endif
 
 # cli: shared between bitcoin-cli and bitcoin-qt
 libbitcoin_cli_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 libbitcoin_cli_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_cli_a_SOURCES = \
   rpc/client.cpp \
   $(BITCOIN_CORE_H)
 
 # seeder library
 libbitcoin_seeder_a_CPPFLAGS = $(AM_CPPFLAGS) $(PIE_FLAGS) $(BITCOIN_SEEDER_INCLUDES)
 libbitcoin_seeder_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_seeder_a_SOURCES = \
   seeder/bitcoin.cpp \
   seeder/bitcoin.h \
   seeder/db.cpp \
   seeder/db.h \
   seeder/dns.cpp \
   seeder/dns.h \
   seeder/util.h
 
 nodist_libbitcoin_util_a_SOURCES = $(srcdir)/obj/build.h
 #
 
 # bitcoind binary #
 bitcoind_SOURCES = bitcoind.cpp
 bitcoind_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 bitcoind_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 bitcoind_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
 bitcoind_SOURCES += bitcoind-res.rc
 endif
 
 bitcoind_LDADD = \
   $(LIBBITCOIN_SERVER) \
   $(LIBBITCOIN_WALLET) \
   $(LIBBITCOIN_SERVER) \
   $(LIBBITCOIN_COMMON) \
   $(LIBUNIVALUE) \
   $(LIBBITCOIN_UTIL) \
   $(LIBBITCOIN_ZMQ) \
   $(LIBBITCOIN_CONSENSUS) \
   $(LIBBITCOIN_CRYPTO) \
   $(LIBLEVELDB) \
   $(LIBLEVELDB_SSE42) \
   $(LIBMEMENV) \
   $(LIBSECP256K1)
 
 bitcoind_LDADD += $(BOOST_LIBS) $(BDB_LIBS) $(MINIUPNPC_LIBS) $(EVENT_PTHREADS_LIBS) $(EVENT_LIBS) $(ZMQ_LIBS)
 
 # bitcoin-cli binary #
 bitcoin_cli_SOURCES = bitcoin-cli.cpp
 bitcoin_cli_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(EVENT_CFLAGS)
 bitcoin_cli_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 bitcoin_cli_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
 bitcoin_cli_SOURCES += bitcoin-cli-res.rc
 endif
 
 bitcoin_cli_LDADD = \
   $(LIBBITCOIN_CLI) \
   $(LIBUNIVALUE) \
   $(LIBBITCOIN_UTIL) \
   $(LIBBITCOIN_CRYPTO)
 
 bitcoin_cli_LDADD += $(BOOST_LIBS) $(EVENT_LIBS)
 #
 
 # bitcoin-seeder binary #
 bitcoin_seeder_SOURCES = seeder/main.cpp
 bitcoin_seeder_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_SEEDER_INCLUDES)
 bitcoin_seeder_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 bitcoin_seeder_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 bitcoin_seeder_LDADD = \
   $(LIBBITCOIN_SEEDER) \
   $(LIBBITCOIN_COMMON) \
   $(LIBBITCOIN_UTIL) \
   $(LIBUNIVALUE) \
   $(LIBBITCOIN_CRYPTO) \
   $(LIBBITCOIN_CONSENSUS)
 
 bitcoin_seeder_LDADD += $(BOOST_LIBS)
 #
 
 # bitcoin-tx binary #
 bitcoin_tx_SOURCES = bitcoin-tx.cpp
 bitcoin_tx_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 bitcoin_tx_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 bitcoin_tx_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
 bitcoin_tx_SOURCES += bitcoin-tx-res.rc
 endif
 
 bitcoin_tx_LDADD = \
   $(LIBUNIVALUE) \
   $(LIBBITCOIN_COMMON) \
   $(LIBBITCOIN_UTIL) \
   $(LIBBITCOIN_CONSENSUS) \
   $(LIBBITCOIN_CRYPTO) \
   $(LIBSECP256K1)
 
 bitcoin_tx_LDADD += $(BOOST_LIBS)
 #
 
 # bitcoin-wallet binary #
 bitcoin_wallet_SOURCES = bitcoin-wallet.cpp
 bitcoin_wallet_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
 bitcoin_wallet_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 bitcoin_wallet_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
 if TARGET_WINDOWS
 bitcoin_wallet_SOURCES += bitcoin-wallet-res.rc
 endif
 
 bitcoin_wallet_LDADD = \
   $(LIBBITCOIN_WALLET_TOOL) \
   $(LIBBITCOIN_WALLET) \
   $(LIBBITCOIN_SERVER) \
   $(LIBBITCOIN_COMMON) \
   $(LIBBITCOIN_CONSENSUS) \
   $(LIBBITCOIN_UTIL) \
   $(LIBBITCOIN_CRYPTO) \
   $(LIBBITCOIN_ZMQ) \
   $(LIBLEVELDB) \
   $(LIBLEVELDB_SSE42) \
   $(LIBMEMENV) \
   $(LIBSECP256K1) \
   $(LIBUNIVALUE)
 
 bitcoin_wallet_LDADD += $(BOOST_LIBS) $(BDB_LIBS) $(EVENT_PTHREADS_LIBS) $(EVENT_LIBS) $(MINIUPNPC_LIBS) $(ZMQ_LIBS)
 #
 
 # bitcoinconsensus library #
 if BUILD_BITCOIN_LIBS
 include_HEADERS = script/bitcoinconsensus.h
 libbitcoinconsensus_la_SOURCES = $(crypto_libbitcoin_crypto_base_a_SOURCES) $(libbitcoin_consensus_a_SOURCES)
 
 if GLIBC_BACK_COMPAT
   libbitcoinconsensus_la_SOURCES += compat/glibc_compat.cpp
 endif
 
 libbitcoinconsensus_la_LDFLAGS = $(AM_LDFLAGS) -no-undefined $(RELDFLAGS)
 libbitcoinconsensus_la_LIBADD = $(LIBSECP256K1)
 libbitcoinconsensus_la_CPPFLAGS = $(AM_CPPFLAGS) -I$(builddir)/obj -I$(srcdir)/secp256k1/include -DBUILD_BITCOIN_INTERNAL
 libbitcoinconsensus_la_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 
 endif
 #
 
 CTAES_DIST =  crypto/ctaes/bench.c
 CTAES_DIST += crypto/ctaes/ctaes.c
 CTAES_DIST += crypto/ctaes/ctaes.h
 CTAES_DIST += crypto/ctaes/README.md
 CTAES_DIST += crypto/ctaes/test.c
 
 CLEANFILES = $(EXTRA_LIBRARIES)
 
 CLEANFILES += *.gcda *.gcno
 CLEANFILES += compat/*.gcda compat/*.gcno
 CLEANFILES += consensus/*.gcda consensus/*.gcno
 CLEANFILES += crypto/*.gcda crypto/*.gcno
 CLEANFILES += policy/*.gcda policy/*.gcno
 CLEANFILES += primitives/*.gcda primitives/*.gcno
 CLEANFILES += script/*.gcda script/*.gcno
 CLEANFILES += support/*.gcda support/*.gcno
 CLEANFILES += univalue/*.gcda univalue/*.gcno
 CLEANFILES += wallet/*.gcda wallet/*.gcno
 CLEANFILES += wallet/test/*.gcda wallet/test/*.gcno
 CLEANFILES += zmq/*.gcda zmq/*.gcno
 CLEANFILES += obj/build.h
 
 EXTRA_DIST = $(CTAES_DIST)
 
 
 config/bitcoin-config.h: config/stamp-h1
 	@$(MAKE) -C $(top_builddir) $(subdir)/$(@)
 config/stamp-h1: $(top_srcdir)/$(subdir)/config/bitcoin-config.h.in $(top_builddir)/config.status
 	$(AM_V_at)$(MAKE) -C $(top_builddir) $(subdir)/$(@)
 $(top_srcdir)/$(subdir)/config/bitcoin-config.h.in:  $(am__configure_deps)
 	$(AM_V_at)$(MAKE) -C $(top_srcdir) $(subdir)/config/bitcoin-config.h.in
 
 clean-local:
 	-$(MAKE) -C secp256k1 clean
 	-$(MAKE) -C univalue clean
 	-rm -f leveldb/*/*.gcda leveldb/*/*.gcno leveldb/helpers/memenv/*.gcda leveldb/helpers/memenv/*.gcno
 	-rm -rf test/__pycache__
 
 .rc.o:
 	@test -f $(WINDRES)
 	## FIXME: How to get the appropriate modulename_CPPFLAGS in here?
 	$(AM_V_GEN) $(WINDRES) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(CPPFLAGS) -DWINDRES_PREPROC -i $< -o $@
 
 .mm.o:
 	$(AM_V_CXX) $(OBJCXX) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
 	  $(CPPFLAGS) $(AM_CXXFLAGS) $(QT_INCLUDES) $(AM_CXXFLAGS) $(PIE_FLAGS) $(CXXFLAGS) -c -o $@ $<
 
 check-symbols: $(bin_PROGRAMS)
 if GLIBC_BACK_COMPAT
 	@echo "Checking glibc back compat..."
 	$(AM_V_at) READELF=$(READELF) CPPFILT=$(CPPFILT) $(PYTHON) $(top_srcdir)/contrib/devtools/symbol-check.py < $(bin_PROGRAMS)
 endif
 
 check-security: $(bin_PROGRAMS)
 if HARDEN
 	@echo "Checking binary security..."
 	$(AM_V_at) READELF=$(READELF) OBJDUMP=$(OBJDUMP) $(PYTHON) $(top_srcdir)/contrib/devtools/security-check.py < $(bin_PROGRAMS)
 endif
 
 if ENABLE_BIP70
 %.pb.cc %.pb.h: %.proto
 	@test -f $(PROTOC)
 	$(AM_V_GEN) $(PROTOC) --cpp_out=$(@D) --proto_path=$(<D) $<
 endif
 
 if EMBEDDED_LEVELDB
 include Makefile.leveldb.include
 endif
 
 if ENABLE_TESTS
 include Makefile.test.include
 endif
 
 if ENABLE_BENCH
 include Makefile.bench.include
 endif
 
 if ENABLE_QT
 include Makefile.qt.include
 endif
 
 if ENABLE_QT_TESTS
 include Makefile.qttest.include
 endif
 
 if ENABLE_SEEDER_TESTS
 include Makefile.seedertest.include
 endif
diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp
index 2ce8739d0..22fa1b816 100644
--- a/src/rpc/util.cpp
+++ b/src/rpc/util.cpp
@@ -1,673 +1,670 @@
 // Copyright (c) 2017-2019 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 <key_io.h>
 #include <keystore.h>
 #include <pubkey.h>
 #include <rpc/util.h>
 #include <tinyformat.h>
 #include <util/strencodings.h>
+#include <util/string.h>
 
 #include <univalue.h>
 
 #include <boost/variant/static_visitor.hpp>
 
 NodeContext *g_rpc_node = nullptr;
 
 void RPCTypeCheck(const UniValue &params,
                   const std::list<UniValueType> &typesExpected,
                   bool fAllowNull) {
     unsigned int i = 0;
     for (const UniValueType &t : typesExpected) {
         if (params.size() <= i) {
             break;
         }
 
         const UniValue &v = params[i];
         if (!(fAllowNull && v.isNull())) {
             RPCTypeCheckArgument(v, t);
         }
         i++;
     }
 }
 
 void RPCTypeCheckArgument(const UniValue &value,
                           const UniValueType &typeExpected) {
     if (!typeExpected.typeAny && value.type() != typeExpected.type) {
         throw JSONRPCError(RPC_TYPE_ERROR,
                            strprintf("Expected type %s, got %s",
                                      uvTypeName(typeExpected.type),
                                      uvTypeName(value.type())));
     }
 }
 
 void RPCTypeCheckObj(const UniValue &o,
                      const std::map<std::string, UniValueType> &typesExpected,
                      bool fAllowNull, bool fStrict) {
     for (const auto &t : typesExpected) {
         const UniValue &v = find_value(o, t.first);
         if (!fAllowNull && v.isNull()) {
             throw JSONRPCError(RPC_TYPE_ERROR,
                                strprintf("Missing %s", t.first));
         }
 
         if (!(t.second.typeAny || v.type() == t.second.type ||
               (fAllowNull && v.isNull()))) {
             std::string err = strprintf("Expected type %s for %s, got %s",
                                         uvTypeName(t.second.type), t.first,
                                         uvTypeName(v.type()));
             throw JSONRPCError(RPC_TYPE_ERROR, err);
         }
     }
 
     if (fStrict) {
         for (const std::string &k : o.getKeys()) {
             if (typesExpected.count(k) == 0) {
                 std::string err = strprintf("Unexpected key %s", k);
                 throw JSONRPCError(RPC_TYPE_ERROR, err);
             }
         }
     }
 }
 
 Amount AmountFromValue(const UniValue &value) {
     if (!value.isNum() && !value.isStr()) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Amount is not a number or string");
     }
 
     int64_t n;
     if (!ParseFixedPoint(value.getValStr(), 8, &n)) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount");
     }
 
     Amount amt = n * SATOSHI;
     if (!MoneyRange(amt)) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Amount out of range");
     }
 
     return amt;
 }
 
 uint256 ParseHashV(const UniValue &v, std::string strName) {
     std::string strHex(v.get_str());
     if (64 != strHex.length()) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             strprintf("%s must be of length %d (not %d, for '%s')", strName, 64,
                       strHex.length(), strHex));
     }
     // Note: IsHex("") is false
     if (!IsHex(strHex)) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strName + " must be hexadecimal string (not '" +
                                strHex + "')");
     }
     return uint256S(strHex);
 }
 
 uint256 ParseHashO(const UniValue &o, std::string strKey) {
     return ParseHashV(find_value(o, strKey), strKey);
 }
 
 std::vector<uint8_t> ParseHexV(const UniValue &v, std::string strName) {
     std::string strHex;
     if (v.isStr()) {
         strHex = v.get_str();
     }
     if (!IsHex(strHex)) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strName + " must be hexadecimal string (not '" +
                                strHex + "')");
     }
 
     return ParseHex(strHex);
 }
 
 std::vector<uint8_t> ParseHexO(const UniValue &o, std::string strKey) {
     return ParseHexV(find_value(o, strKey), strKey);
 }
 
 std::string HelpExampleCli(const std::string &methodname,
                            const std::string &args) {
     return "> bitcoin-cli " + methodname + " " + args + "\n";
 }
 
 std::string HelpExampleRpc(const std::string &methodname,
                            const std::string &args) {
     return "> curl --user myusername --data-binary '{\"jsonrpc\": \"1.0\", "
            "\"id\":\"curltest\", "
            "\"method\": \"" +
            methodname + "\", \"params\": [" + args +
            "] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/\n";
 }
 
 // Converts a hex string to a public key if possible
 CPubKey HexToPubKey(const std::string &hex_in) {
     if (!IsHex(hex_in)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid public key: " + hex_in);
     }
     CPubKey vchPubKey(ParseHex(hex_in));
     if (!vchPubKey.IsFullyValid()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid public key: " + hex_in);
     }
     return vchPubKey;
 }
 
 // Retrieves a public key for an address from the given CKeyStore
 CPubKey AddrToPubKey(const CChainParams &chainparams, CKeyStore *const keystore,
                      const std::string &addr_in) {
     CTxDestination dest = DecodeDestination(addr_in, chainparams);
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid address: " + addr_in);
     }
     CKeyID key = GetKeyForDestination(*keystore, dest);
     if (key.IsNull()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            strprintf("%s does not refer to a key", addr_in));
     }
     CPubKey vchPubKey;
     if (!keystore->GetPubKey(key, vchPubKey)) {
         throw JSONRPCError(
             RPC_INVALID_ADDRESS_OR_KEY,
             strprintf("no full public key for address %s", addr_in));
     }
     if (!vchPubKey.IsFullyValid()) {
         throw JSONRPCError(RPC_INTERNAL_ERROR,
                            "Wallet contains an invalid public key");
     }
     return vchPubKey;
 }
 
 // Creates a multisig redeemscript from a given list of public keys and number
 // required.
 CScript CreateMultisigRedeemscript(const int required,
                                    const std::vector<CPubKey> &pubkeys) {
     // Gather public keys
     if (required < 1) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             "a multisignature address must require at least one key to redeem");
     }
     if ((int)pubkeys.size() < required) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strprintf("not enough keys supplied (got %u keys, "
                                      "but need at least %d to redeem)",
                                      pubkeys.size(), required));
     }
     if (pubkeys.size() > 16) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "Number of keys involved in the multisignature "
                            "address creation > 16\nReduce the number");
     }
 
     CScript result = GetScriptForMultisig(required, pubkeys);
 
     if (result.size() > MAX_SCRIPT_ELEMENT_SIZE) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             (strprintf("redeemScript exceeds size limit: %d > %d",
                        result.size(), MAX_SCRIPT_ELEMENT_SIZE)));
     }
 
     return result;
 }
 
 class DescribeAddressVisitor : public boost::static_visitor<UniValue> {
 public:
     explicit DescribeAddressVisitor() {}
 
     UniValue operator()(const CNoDestination &dest) const {
         return UniValue(UniValue::VOBJ);
     }
 
     UniValue operator()(const CKeyID &keyID) const {
         UniValue obj(UniValue::VOBJ);
         obj.pushKV("isscript", false);
         return obj;
     }
 
     UniValue operator()(const CScriptID &scriptID) const {
         UniValue obj(UniValue::VOBJ);
         obj.pushKV("isscript", true);
         return obj;
     }
 };
 
 UniValue DescribeAddress(const CTxDestination &dest) {
     return boost::apply_visitor(DescribeAddressVisitor(), dest);
 }
 
 RPCErrorCode RPCErrorFromTransactionError(TransactionError terr) {
     switch (terr) {
         case TransactionError::MEMPOOL_REJECTED:
             return RPC_TRANSACTION_REJECTED;
         case TransactionError::ALREADY_IN_CHAIN:
             return RPC_TRANSACTION_ALREADY_IN_CHAIN;
         case TransactionError::P2P_DISABLED:
             return RPC_CLIENT_P2P_DISABLED;
         case TransactionError::INVALID_PSBT:
         case TransactionError::PSBT_MISMATCH:
             return RPC_INVALID_PARAMETER;
         case TransactionError::SIGHASH_MISMATCH:
             return RPC_DESERIALIZATION_ERROR;
         default:
             break;
     }
     return RPC_TRANSACTION_ERROR;
 }
 
 UniValue JSONRPCTransactionError(TransactionError terr,
                                  const std::string &err_string) {
     if (err_string.length() > 0) {
         return JSONRPCError(RPCErrorFromTransactionError(terr), err_string);
     } else {
         return JSONRPCError(RPCErrorFromTransactionError(terr),
                             TransactionErrorString(terr));
     }
 }
 
 /**
  * A pair of strings that can be aligned (through padding) with other Sections
  * later on
  */
 struct Section {
     Section(const std::string &left, const std::string &right)
         : m_left{left}, m_right{right} {}
     const std::string m_left;
     const std::string m_right;
 };
 
 /**
  * Keeps track of RPCArgs by transforming them into sections for the purpose
  * of serializing everything to a single string
  */
 struct Sections {
     std::vector<Section> m_sections;
     size_t m_max_pad{0};
 
     void PushSection(const Section &s) {
         m_max_pad = std::max(m_max_pad, s.m_left.size());
         m_sections.push_back(s);
     }
 
     /**
      * Serializing RPCArgs depends on the outer type. Only arrays and
      * dictionaries can be nested in json. The top-level outer type is "named
      * arguments", a mix between a dictionary and arrays.
      */
     enum class OuterType {
         ARR,
         OBJ,
         // Only set on first recursion
         NAMED_ARG,
     };
 
     /**
      * Recursive helper to translate an RPCArg into sections
      */
     void Push(const RPCArg &arg, const size_t current_indent = 5,
               const OuterType outer_type = OuterType::NAMED_ARG) {
         const auto indent = std::string(current_indent, ' ');
         const auto indent_next = std::string(current_indent + 2, ' ');
         // Dictionary keys must have a name
         const bool push_name{outer_type == OuterType::OBJ};
 
         switch (arg.m_type) {
             case RPCArg::Type::STR_HEX:
             case RPCArg::Type::STR:
             case RPCArg::Type::NUM:
             case RPCArg::Type::AMOUNT:
             case RPCArg::Type::BOOL: {
                 // Nothing more to do for non-recursive types on first recursion
                 if (outer_type == OuterType::NAMED_ARG) {
                     return;
                 }
                 auto left = indent;
                 if (arg.m_type_str.size() != 0 && push_name) {
                     left += "\"" + arg.m_name + "\": " + arg.m_type_str.at(0);
                 } else {
                     left += push_name ? arg.ToStringObj(/* oneline */ false)
                                       : arg.ToString(/* oneline */ false);
                 }
                 left += ",";
                 PushSection({left, arg.ToDescriptionString()});
                 break;
             }
             case RPCArg::Type::OBJ:
             case RPCArg::Type::OBJ_USER_KEYS: {
                 const auto right = outer_type == OuterType::NAMED_ARG
                                        ? ""
                                        : arg.ToDescriptionString();
                 PushSection({indent +
                                  (push_name ? "\"" + arg.m_name + "\": " : "") +
                                  "{",
                              right});
                 for (const auto &arg_inner : arg.m_inner) {
                     Push(arg_inner, current_indent + 2, OuterType::OBJ);
                 }
                 if (arg.m_type != RPCArg::Type::OBJ) {
                     PushSection({indent_next + "...", ""});
                 }
                 PushSection(
                     {indent + "}" +
                          (outer_type != OuterType::NAMED_ARG ? "," : ""),
                      ""});
                 break;
             }
             case RPCArg::Type::ARR: {
                 auto left = indent;
                 left += push_name ? "\"" + arg.m_name + "\": " : "";
                 left += "[";
                 const auto right = outer_type == OuterType::NAMED_ARG
                                        ? ""
                                        : arg.ToDescriptionString();
                 PushSection({left, right});
                 for (const auto &arg_inner : arg.m_inner) {
                     Push(arg_inner, current_indent + 2, OuterType::ARR);
                 }
                 PushSection({indent_next + "...", ""});
                 PushSection(
                     {indent + "]" +
                          (outer_type != OuterType::NAMED_ARG ? "," : ""),
                      ""});
                 break;
             }
 
                 // no default case, so the compiler can warn about missing cases
         }
     }
 
     /**
      * Concatenate all sections with proper padding
      */
     std::string ToString() const {
         std::string ret;
         const size_t pad = m_max_pad + 4;
         for (const auto &s : m_sections) {
             if (s.m_right.empty()) {
                 ret += s.m_left;
                 ret += "\n";
                 continue;
             }
 
             std::string left = s.m_left;
             left.resize(pad, ' ');
             ret += left;
 
             // Properly pad after newlines
             std::string right;
             size_t begin = 0;
             size_t new_line_pos = s.m_right.find_first_of('\n');
             while (true) {
                 right += s.m_right.substr(begin, new_line_pos - begin);
                 if (new_line_pos == std::string::npos) {
                     // No new line
                     break;
                 }
                 right += "\n" + std::string(pad, ' ');
                 begin = s.m_right.find_first_not_of(' ', new_line_pos + 1);
                 if (begin == std::string::npos) {
                     break; // Empty line
                 }
                 new_line_pos = s.m_right.find_first_of('\n', begin + 1);
             }
             ret += right;
             ret += "\n";
         }
         return ret;
     }
 };
 
 RPCHelpMan::RPCHelpMan(std::string name, std::string description,
                        std::vector<RPCArg> args, RPCResults results,
                        RPCExamples examples)
     : m_name{std::move(name)}, m_description{std::move(description)},
       m_args{std::move(args)}, m_results{std::move(results)},
       m_examples{std::move(examples)} {
     std::set<std::string> named_args;
     for (const auto &arg : m_args) {
         // Should have unique named arguments
         CHECK_NONFATAL(named_args.insert(arg.m_name).second);
     }
 }
 
 std::string RPCResults::ToDescriptionString() const {
     std::string result;
     for (const auto &r : m_results) {
         if (r.m_cond.empty()) {
             result += "\nResult:\n";
         } else {
             result += "\nResult (" + r.m_cond + "):\n";
         }
         result += r.m_result;
     }
     return result;
 }
 
 std::string RPCExamples::ToDescriptionString() const {
     return m_examples.empty() ? m_examples : "\nExamples:\n" + m_examples;
 }
 
 bool RPCHelpMan::IsValidNumArgs(size_t num_args) const {
     size_t num_required_args = 0;
     for (size_t n = m_args.size(); n > 0; --n) {
         if (!m_args.at(n - 1).IsOptional()) {
             num_required_args = n;
             break;
         }
     }
     return num_required_args <= num_args && num_args <= m_args.size();
 }
 std::string RPCHelpMan::ToString() const {
     std::string ret;
 
     // Oneline summary
     ret += m_name;
     bool was_optional{false};
     for (const auto &arg : m_args) {
         const bool optional = arg.IsOptional();
         ret += " ";
         if (optional) {
             if (!was_optional) {
                 ret += "( ";
             }
             was_optional = true;
         } else {
             if (was_optional) {
                 ret += ") ";
             }
             was_optional = false;
         }
         ret += arg.ToString(/* oneline */ true);
     }
     if (was_optional) {
         ret += " )";
     }
     ret += "\n";
 
     // Description
     ret += m_description;
 
     // Arguments
     Sections sections;
     for (size_t i{0}; i < m_args.size(); ++i) {
         const auto &arg = m_args.at(i);
 
         if (i == 0) {
             ret += "\nArguments:\n";
         }
 
         // Push named argument name and description
         sections.m_sections.emplace_back(std::to_string(i + 1) + ". " +
                                              arg.m_name,
                                          arg.ToDescriptionString());
         sections.m_max_pad = std::max(sections.m_max_pad,
                                       sections.m_sections.back().m_left.size());
 
         // Recursively push nested args
         sections.Push(arg);
     }
     ret += sections.ToString();
 
     // Result
     ret += m_results.ToDescriptionString();
 
     // Examples
     ret += m_examples.ToDescriptionString();
 
     return ret;
 }
 
 bool RPCArg::IsOptional() const {
     if (m_fallback.which() == 1) {
         return true;
     } else {
         return RPCArg::Optional::NO != boost::get<RPCArg::Optional>(m_fallback);
     }
 }
 
 std::string RPCArg::ToDescriptionString() const {
     std::string ret;
     ret += "(";
     if (m_type_str.size() != 0) {
         ret += m_type_str.at(1);
     } else {
         switch (m_type) {
             case Type::STR_HEX:
             case Type::STR: {
                 ret += "string";
                 break;
             }
             case Type::NUM: {
                 ret += "numeric";
                 break;
             }
             case Type::AMOUNT: {
                 ret += "numeric or string";
                 break;
             }
             case Type::BOOL: {
                 ret += "boolean";
                 break;
             }
             case Type::OBJ:
             case Type::OBJ_USER_KEYS: {
                 ret += "json object";
                 break;
             }
             case Type::ARR: {
                 ret += "json array";
                 break;
             }
 
                 // no default case, so the compiler can warn about missing cases
         }
     }
     if (m_fallback.which() == 1) {
         ret += ", optional, default=" + boost::get<std::string>(m_fallback);
     } else {
         switch (boost::get<RPCArg::Optional>(m_fallback)) {
             case RPCArg::Optional::OMITTED: {
                 // nothing to do. Element is treated as if not present and has
                 // no default value
                 break;
             }
             case RPCArg::Optional::OMITTED_NAMED_ARG: {
                 ret += ", optional"; // Default value is "null"
                 break;
             }
             case RPCArg::Optional::NO: {
                 ret += ", required";
                 break;
             }
 
                 // no default case, so the compiler can warn about missing cases
         }
     }
     ret += ")";
     ret += m_description.empty() ? "" : " " + m_description;
     return ret;
 }
 
 std::string RPCArg::ToStringObj(const bool oneline) const {
     std::string res;
     res += "\"";
     res += m_name;
     if (oneline) {
         res += "\":";
     } else {
         res += "\": ";
     }
     switch (m_type) {
         case Type::STR:
             return res + "\"str\"";
         case Type::STR_HEX:
             return res + "\"hex\"";
         case Type::NUM:
             return res + "n";
         case Type::AMOUNT:
             return res + "amount";
         case Type::BOOL:
             return res + "bool";
         case Type::ARR:
             res += "[";
             for (const auto &i : m_inner) {
                 res += i.ToString(oneline) + ",";
             }
             return res + "...]";
         case Type::OBJ:
         case Type::OBJ_USER_KEYS:
             // Currently unused, so avoid writing dead code
             assert(false);
 
             // no default case, so the compiler can warn about missing cases
     }
     assert(false);
 }
 
 std::string RPCArg::ToString(const bool oneline) const {
     if (oneline && !m_oneline_description.empty()) {
         return m_oneline_description;
     }
 
     switch (m_type) {
         case Type::STR_HEX:
         case Type::STR: {
             return "\"" + m_name + "\"";
         }
         case Type::NUM:
         case Type::AMOUNT:
         case Type::BOOL: {
             return m_name;
         }
         case Type::OBJ:
         case Type::OBJ_USER_KEYS: {
-            std::string res;
-            for (size_t i = 0; i < m_inner.size();) {
-                res += m_inner[i].ToStringObj(oneline);
-                if (++i < m_inner.size()) {
-                    res += ",";
-                }
-            }
+            const std::string res = Join(m_inner, ",", [&](const RPCArg &i) {
+                return i.ToStringObj(oneline);
+            });
             if (m_type == Type::OBJ) {
                 return "{" + res + "}";
             } else {
                 return "{" + res + ",...}";
             }
         }
         case Type::ARR: {
             std::string res;
             for (const auto &i : m_inner) {
                 res += i.ToString(oneline) + ",";
             }
             return "[" + res + "...]";
         }
 
             // no default case, so the compiler can warn about missing cases
     }
     assert(false);
 }
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 14437e64a..263ae5a97 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -1,2058 +1,2073 @@
 // Copyright (c) 2011-2019 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 <util/system.h>
 
 #include <clientversion.h>
 #include <optional.h>
 #include <sync.h>
 #include <test/util.h>
 #include <util/moneystr.h>
 #include <util/strencodings.h>
+#include <util/string.h>
 #include <util/time.h>
 
 #include <test/util/setup_common.h>
 
 #include <univalue.h>
 
 #include <boost/test/unit_test.hpp>
 
 #include <cstdint>
 #include <utility>
 #ifndef WIN32
 #include <csignal>
 #include <sys/types.h>
 #include <sys/wait.h>
 #endif
 #include <thread>
 #include <vector>
 
 BOOST_FIXTURE_TEST_SUITE(util_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(util_criticalsection) {
     RecursiveMutex cs;
 
     do {
         LOCK(cs);
         break;
 
         BOOST_ERROR("break was swallowed!");
     } while (0);
 
     do {
         TRY_LOCK(cs, lockTest);
         if (lockTest) {
             // Needed to suppress "Test case [...] did not check any assertions"
             BOOST_CHECK(true);
             break;
         }
 
         BOOST_ERROR("break was swallowed!");
     } while (0);
 }
 
 static const uint8_t ParseHex_expected[65] = {
     0x04, 0x67, 0x8a, 0xfd, 0xb0, 0xfe, 0x55, 0x48, 0x27, 0x19, 0x67,
     0xf1, 0xa6, 0x71, 0x30, 0xb7, 0x10, 0x5c, 0xd6, 0xa8, 0x28, 0xe0,
     0x39, 0x09, 0xa6, 0x79, 0x62, 0xe0, 0xea, 0x1f, 0x61, 0xde, 0xb6,
     0x49, 0xf6, 0xbc, 0x3f, 0x4c, 0xef, 0x38, 0xc4, 0xf3, 0x55, 0x04,
     0xe5, 0x1e, 0xc1, 0x12, 0xde, 0x5c, 0x38, 0x4d, 0xf7, 0xba, 0x0b,
     0x8d, 0x57, 0x8a, 0x4c, 0x70, 0x2b, 0x6b, 0xf1, 0x1d, 0x5f};
 BOOST_AUTO_TEST_CASE(util_ParseHex) {
     std::vector<uint8_t> result;
     std::vector<uint8_t> expected(
         ParseHex_expected, ParseHex_expected + sizeof(ParseHex_expected));
     // Basic test vector
     result = ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0"
                       "ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d"
                       "578a4c702b6bf11d5f");
     BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(),
                                   expected.begin(), expected.end());
 
     // Spaces between bytes must be supported
     result = ParseHex("12 34 56 78");
     BOOST_CHECK(result.size() == 4 && result[0] == 0x12 && result[1] == 0x34 &&
                 result[2] == 0x56 && result[3] == 0x78);
 
     // Leading space must be supported (used in BerkeleyEnvironment::Salvage)
     result = ParseHex(" 89 34 56 78");
     BOOST_CHECK(result.size() == 4 && result[0] == 0x89 && result[1] == 0x34 &&
                 result[2] == 0x56 && result[3] == 0x78);
 
     // Stop parsing at invalid value
     result = ParseHex("1234 invalid 1234");
     BOOST_CHECK(result.size() == 2 && result[0] == 0x12 && result[1] == 0x34);
 }
 
 BOOST_AUTO_TEST_CASE(util_HexStr) {
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected,
                              ParseHex_expected + sizeof(ParseHex_expected)),
                       "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0"
                       "ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d"
                       "578a4c702b6bf11d5f");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected + 5, true),
                       "04 67 8a fd b0");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected + sizeof(ParseHex_expected),
                              ParseHex_expected + sizeof(ParseHex_expected)),
                       "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected + sizeof(ParseHex_expected),
                              ParseHex_expected + sizeof(ParseHex_expected),
                              true),
                       "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected), "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected, true), "");
 
     std::vector<uint8_t> ParseHex_vec(ParseHex_expected, ParseHex_expected + 5);
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec, true), "04 67 8a fd b0");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec.rbegin(), ParseHex_vec.rend()),
                       "b0fd8a6704");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec.rbegin(), ParseHex_vec.rend(), true),
                       "b0 fd 8a 67 04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 1),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 1),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 5),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "b0fd8a6704");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 5),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "b0 fd 8a 67 04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 65),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "5f1df16b2b704c8a578d0bbaf74d385cde12c11ee50455f3c438ef4c3fbcf649b6de61"
         "1feae06279a60939e028a8d65c10b73071a6f16719274855feb0fd8a6704");
 }
 
+BOOST_AUTO_TEST_CASE(util_Join) {
+    // Normal version
+    BOOST_CHECK_EQUAL(Join({}, ", "), "");
+    BOOST_CHECK_EQUAL(Join({"foo"}, ", "), "foo");
+    BOOST_CHECK_EQUAL(Join({"foo", "bar"}, ", "), "foo, bar");
+
+    // Version with unary operator
+    const auto op_upper = [](const std::string &s) { return ToUpper(s); };
+    BOOST_CHECK_EQUAL(Join<std::string>({}, ", ", op_upper), "");
+    BOOST_CHECK_EQUAL(Join<std::string>({"foo"}, ", ", op_upper), "FOO");
+    BOOST_CHECK_EQUAL(Join<std::string>({"foo", "bar"}, ", ", op_upper),
+                      "FOO, BAR");
+}
+
 BOOST_AUTO_TEST_CASE(util_FormatParseISO8601DateTime) {
     BOOST_CHECK_EQUAL(FormatISO8601DateTime(1317425777),
                       "2011-09-30T23:36:17Z");
     BOOST_CHECK_EQUAL(FormatISO8601DateTime(0), "1970-01-01T00:00:00Z");
 
     BOOST_CHECK_EQUAL(ParseISO8601DateTime("1970-01-01T00:00:00Z"), 0);
     BOOST_CHECK_EQUAL(ParseISO8601DateTime("1960-01-01T00:00:00Z"), 0);
     BOOST_CHECK_EQUAL(ParseISO8601DateTime("2011-09-30T23:36:17Z"), 1317425777);
 
     auto time = GetSystemTimeInSeconds();
     BOOST_CHECK_EQUAL(ParseISO8601DateTime(FormatISO8601DateTime(time)), time);
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatISO8601Date) {
     BOOST_CHECK_EQUAL(FormatISO8601Date(1317425777), "2011-09-30");
 }
 
 struct TestArgsManager : public ArgsManager {
     TestArgsManager() { m_network_only_args.clear(); }
     void ReadConfigString(const std::string str_config) {
         std::istringstream streamConfig(str_config);
         {
             LOCK(cs_args);
             m_settings.ro_config.clear();
             m_config_sections.clear();
         }
         std::string error;
         BOOST_REQUIRE(ReadConfigStream(streamConfig, "", error));
     }
     void SetNetworkOnlyArg(const std::string arg) {
         LOCK(cs_args);
         m_network_only_args.insert(arg);
     }
     void
     SetupArgs(const std::vector<std::pair<std::string, unsigned int>> &args) {
         for (const auto &arg : args) {
             AddArg(arg.first, "", arg.second, OptionsCategory::OPTIONS);
         }
     }
     using ArgsManager::cs_args;
     using ArgsManager::GetSetting;
     using ArgsManager::GetSettingsList;
     using ArgsManager::m_network;
     using ArgsManager::m_settings;
     using ArgsManager::ReadConfigStream;
 };
 
 //! Test GetSetting and GetArg type coercion, negation, and default value
 //! handling.
 class CheckValueTest : public TestChain100Setup {
 public:
     struct Expect {
         util::SettingsValue setting;
         bool default_string = false;
         bool default_int = false;
         bool default_bool = false;
         const char *string_value = nullptr;
         Optional<int64_t> int_value;
         Optional<bool> bool_value;
         Optional<std::vector<std::string>> list_value;
         const char *error = nullptr;
 
         Expect(util::SettingsValue s) : setting(std::move(s)) {}
         Expect &DefaultString() {
             default_string = true;
             return *this;
         }
         Expect &DefaultInt() {
             default_int = true;
             return *this;
         }
         Expect &DefaultBool() {
             default_bool = true;
             return *this;
         }
         Expect &String(const char *s) {
             string_value = s;
             return *this;
         }
         Expect &Int(int64_t i) {
             int_value = i;
             return *this;
         }
         Expect &Bool(bool b) {
             bool_value = b;
             return *this;
         }
         Expect &List(std::vector<std::string> m) {
             list_value = std::move(m);
             return *this;
         }
         Expect &Error(const char *e) {
             error = e;
             return *this;
         }
     };
 
     void CheckValue(unsigned int flags, const char *arg, const Expect &expect) {
         TestArgsManager test;
         test.SetupArgs({{"-value", flags}});
         const char *argv[] = {"ignored", arg};
         std::string error;
         bool success = test.ParseParameters(arg ? 2 : 1, (char **)argv, error);
 
         BOOST_CHECK_EQUAL(test.GetSetting("-value").write(),
                           expect.setting.write());
         auto settings_list = test.GetSettingsList("-value");
         if (expect.setting.isNull() || expect.setting.isFalse()) {
             BOOST_CHECK_EQUAL(settings_list.size(), 0);
         } else {
             BOOST_CHECK_EQUAL(settings_list.size(), 1);
             BOOST_CHECK_EQUAL(settings_list[0].write(), expect.setting.write());
         }
 
         if (expect.error) {
             BOOST_CHECK(!success);
             BOOST_CHECK_NE(error.find(expect.error), std::string::npos);
         } else {
             BOOST_CHECK(success);
             BOOST_CHECK_EQUAL(error, "");
         }
 
         if (expect.default_string) {
             BOOST_CHECK_EQUAL(test.GetArg("-value", "zzzzz"), "zzzzz");
         } else if (expect.string_value) {
             BOOST_CHECK_EQUAL(test.GetArg("-value", "zzzzz"),
                               expect.string_value);
         } else {
             BOOST_CHECK(!success);
         }
 
         if (expect.default_int) {
             BOOST_CHECK_EQUAL(test.GetArg("-value", 99999), 99999);
         } else if (expect.int_value) {
             BOOST_CHECK_EQUAL(test.GetArg("-value", 99999), *expect.int_value);
         } else {
             BOOST_CHECK(!success);
         }
 
         if (expect.default_bool) {
             BOOST_CHECK_EQUAL(test.GetBoolArg("-value", false), false);
             BOOST_CHECK_EQUAL(test.GetBoolArg("-value", true), true);
         } else if (expect.bool_value) {
             BOOST_CHECK_EQUAL(test.GetBoolArg("-value", false),
                               *expect.bool_value);
             BOOST_CHECK_EQUAL(test.GetBoolArg("-value", true),
                               *expect.bool_value);
         } else {
             BOOST_CHECK(!success);
         }
 
         if (expect.list_value) {
             auto l = test.GetArgs("-value");
             BOOST_CHECK_EQUAL_COLLECTIONS(l.begin(), l.end(),
                                           expect.list_value->begin(),
                                           expect.list_value->end());
         } else {
             BOOST_CHECK(!success);
         }
     }
 };
 
 BOOST_FIXTURE_TEST_CASE(util_CheckValue, CheckValueTest) {
     using M = ArgsManager;
 
     CheckValue(M::ALLOW_ANY, nullptr,
                Expect{{}}.DefaultString().DefaultInt().DefaultBool().List({}));
     CheckValue(M::ALLOW_ANY, "-novalue",
                Expect{false}.String("0").Int(0).Bool(false).List({}));
     CheckValue(M::ALLOW_ANY, "-novalue=",
                Expect{false}.String("0").Int(0).Bool(false).List({}));
     CheckValue(M::ALLOW_ANY, "-novalue=0",
                Expect{true}.String("1").Int(1).Bool(true).List({"1"}));
     CheckValue(M::ALLOW_ANY, "-novalue=1",
                Expect{false}.String("0").Int(0).Bool(false).List({}));
     CheckValue(M::ALLOW_ANY, "-novalue=2",
                Expect{false}.String("0").Int(0).Bool(false).List({}));
     CheckValue(M::ALLOW_ANY, "-novalue=abc",
                Expect{true}.String("1").Int(1).Bool(true).List({"1"}));
     CheckValue(M::ALLOW_ANY, "-value",
                Expect{""}.String("").Int(0).Bool(true).List({""}));
     CheckValue(M::ALLOW_ANY,
                "-value=", Expect{""}.String("").Int(0).Bool(true).List({""}));
     CheckValue(M::ALLOW_ANY, "-value=0",
                Expect{"0"}.String("0").Int(0).Bool(false).List({"0"}));
     CheckValue(M::ALLOW_ANY, "-value=1",
                Expect{"1"}.String("1").Int(1).Bool(true).List({"1"}));
     CheckValue(M::ALLOW_ANY, "-value=2",
                Expect{"2"}.String("2").Int(2).Bool(true).List({"2"}));
     CheckValue(M::ALLOW_ANY, "-value=abc",
                Expect{"abc"}.String("abc").Int(0).Bool(false).List({"abc"}));
 }
 
 BOOST_AUTO_TEST_CASE(util_ParseParameters) {
     TestArgsManager testArgs;
     const auto a = std::make_pair("-a", ArgsManager::ALLOW_ANY);
     const auto b = std::make_pair("-b", ArgsManager::ALLOW_ANY);
     const auto ccc = std::make_pair("-ccc", ArgsManager::ALLOW_ANY);
     const auto d = std::make_pair("-d", ArgsManager::ALLOW_ANY);
 
     const char *argv_test[] = {"-ignored",      "-a", "-b",  "-ccc=argument",
                                "-ccc=multiple", "f",  "-d=e"};
 
     std::string error;
     LOCK(testArgs.cs_args);
     testArgs.SetupArgs({a, b, ccc, d});
     BOOST_CHECK(testArgs.ParseParameters(0, (char **)argv_test, error));
     BOOST_CHECK(testArgs.m_settings.command_line_options.empty() &&
                 testArgs.m_settings.ro_config.empty());
 
     BOOST_CHECK(testArgs.ParseParameters(1, (char **)argv_test, error));
     BOOST_CHECK(testArgs.m_settings.command_line_options.empty() &&
                 testArgs.m_settings.ro_config.empty());
 
     BOOST_CHECK(testArgs.ParseParameters(7, (char **)argv_test, error));
     // expectation: -ignored is ignored (program name argument),
     // -a, -b and -ccc end up in map, -d ignored because it is after
     // a non-option argument (non-GNU option parsing)
     BOOST_CHECK(testArgs.m_settings.command_line_options.size() == 3 &&
                 testArgs.m_settings.ro_config.empty());
     BOOST_CHECK(testArgs.IsArgSet("-a") && testArgs.IsArgSet("-b") &&
                 testArgs.IsArgSet("-ccc") && !testArgs.IsArgSet("f") &&
                 !testArgs.IsArgSet("-d"));
     BOOST_CHECK(testArgs.m_settings.command_line_options.count("a") &&
                 testArgs.m_settings.command_line_options.count("b") &&
                 testArgs.m_settings.command_line_options.count("ccc") &&
                 !testArgs.m_settings.command_line_options.count("f") &&
                 !testArgs.m_settings.command_line_options.count("d"));
 
     BOOST_CHECK(testArgs.m_settings.command_line_options["a"].size() == 1);
     BOOST_CHECK(
         testArgs.m_settings.command_line_options["a"].front().get_str() == "");
     BOOST_CHECK(testArgs.m_settings.command_line_options["ccc"].size() == 2);
     BOOST_CHECK(
         testArgs.m_settings.command_line_options["ccc"].front().get_str() ==
         "argument");
     BOOST_CHECK(
         testArgs.m_settings.command_line_options["ccc"].back().get_str() ==
         "multiple");
     BOOST_CHECK(testArgs.GetArgs("-ccc").size() == 2);
 }
 
 BOOST_AUTO_TEST_CASE(util_ParseKeyValue) {
     {
         std::string key = "badarg";
         std::string value;
         BOOST_CHECK(!ParseKeyValue(key, value));
     }
     {
         std::string key = "badarg=v";
         std::string value;
         BOOST_CHECK(!ParseKeyValue(key, value));
     }
     {
         std::string key = "-a";
         std::string value;
         BOOST_CHECK(ParseKeyValue(key, value));
         BOOST_CHECK_EQUAL(key, "-a");
         BOOST_CHECK_EQUAL(value, "");
     }
     {
         std::string key = "-a=1";
         std::string value;
         BOOST_CHECK(ParseKeyValue(key, value));
         BOOST_CHECK_EQUAL(key, "-a");
         BOOST_CHECK_EQUAL(value, "1");
     }
     {
         std::string key = "--b";
         std::string value;
         BOOST_CHECK(ParseKeyValue(key, value));
         BOOST_CHECK_EQUAL(key, "-b");
         BOOST_CHECK_EQUAL(value, "");
     }
     {
         std::string key = "--b=abc";
         std::string value;
         BOOST_CHECK(ParseKeyValue(key, value));
         BOOST_CHECK_EQUAL(key, "-b");
         BOOST_CHECK_EQUAL(value, "abc");
     }
 }
 
 BOOST_AUTO_TEST_CASE(util_GetBoolArg) {
     TestArgsManager testArgs;
     const auto a = std::make_pair("-a", ArgsManager::ALLOW_ANY);
     const auto b = std::make_pair("-b", ArgsManager::ALLOW_ANY);
     const auto c = std::make_pair("-c", ArgsManager::ALLOW_ANY);
     const auto d = std::make_pair("-d", ArgsManager::ALLOW_ANY);
     const auto e = std::make_pair("-e", ArgsManager::ALLOW_ANY);
     const auto f = std::make_pair("-f", ArgsManager::ALLOW_ANY);
 
     const char *argv_test[] = {"ignored", "-a",       "-nob",   "-c=0",
                                "-d=1",    "-e=false", "-f=true"};
     std::string error;
     LOCK(testArgs.cs_args);
     testArgs.SetupArgs({a, b, c, d, e, f});
     BOOST_CHECK(testArgs.ParseParameters(7, (char **)argv_test, error));
 
     // Each letter should be set.
     for (const char opt : "abcdef") {
         BOOST_CHECK(testArgs.IsArgSet({'-', opt}) || !opt);
     }
 
     // Nothing else should be in the map
     BOOST_CHECK(testArgs.m_settings.command_line_options.size() == 6 &&
                 testArgs.m_settings.ro_config.empty());
 
     // The -no prefix should get stripped on the way in.
     BOOST_CHECK(!testArgs.IsArgSet("-nob"));
 
     // The -b option is flagged as negated, and nothing else is
     BOOST_CHECK(testArgs.IsArgNegated("-b"));
     BOOST_CHECK(!testArgs.IsArgNegated("-a"));
 
     // Check expected values.
     BOOST_CHECK(testArgs.GetBoolArg("-a", false) == true);
     BOOST_CHECK(testArgs.GetBoolArg("-b", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-c", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-d", false) == true);
     BOOST_CHECK(testArgs.GetBoolArg("-e", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-f", true) == false);
 }
 
 BOOST_AUTO_TEST_CASE(util_GetBoolArgEdgeCases) {
     // Test some awful edge cases that hopefully no user will ever exercise.
     TestArgsManager testArgs;
 
     // Params test
     const auto foo = std::make_pair("-foo", ArgsManager::ALLOW_ANY);
     const auto bar = std::make_pair("-bar", ArgsManager::ALLOW_ANY);
     const char *argv_test[] = {"ignored", "-nofoo", "-foo", "-nobar=0"};
     testArgs.SetupArgs({foo, bar});
     std::string error;
     BOOST_CHECK(testArgs.ParseParameters(4, (char **)argv_test, error));
 
     // This was passed twice, second one overrides the negative setting.
     BOOST_CHECK(!testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "");
 
     // A double negative is a positive, and not marked as negated.
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "1");
 
     // Config test
     const char *conf_test = "nofoo=1\nfoo=1\nnobar=0\n";
     BOOST_CHECK(testArgs.ParseParameters(1, (char **)argv_test, error));
     testArgs.ReadConfigString(conf_test);
 
     // This was passed twice, second one overrides the negative setting,
     // and the value.
     BOOST_CHECK(!testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "1");
 
     // A double negative is a positive, and does not count as negated.
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "1");
 
     // Combined test
     const char *combo_test_args[] = {"ignored", "-nofoo", "-bar"};
     const char *combo_test_conf = "foo=1\nnobar=1\n";
     BOOST_CHECK(testArgs.ParseParameters(3, (char **)combo_test_args, error));
     testArgs.ReadConfigString(combo_test_conf);
 
     // Command line overrides, but doesn't erase old setting
     BOOST_CHECK(testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "0");
     BOOST_CHECK(testArgs.GetArgs("-foo").size() == 0);
 
     // Command line overrides, but doesn't erase old setting
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "");
     BOOST_CHECK(testArgs.GetArgs("-bar").size() == 1 &&
                 testArgs.GetArgs("-bar").front() == "");
 }
 
 BOOST_AUTO_TEST_CASE(util_ReadConfigStream) {
     const char *str_config = "a=\n"
                              "b=1\n"
                              "ccc=argument\n"
                              "ccc=multiple\n"
                              "d=e\n"
                              "nofff=1\n"
                              "noggg=0\n"
                              "h=1\n"
                              "noh=1\n"
                              "noi=1\n"
                              "i=1\n"
                              "sec1.ccc=extend1\n"
                              "\n"
                              "[sec1]\n"
                              "ccc=extend2\n"
                              "d=eee\n"
                              "h=1\n"
                              "[sec2]\n"
                              "ccc=extend3\n"
                              "iii=2\n";
 
     TestArgsManager test_args;
     LOCK(test_args.cs_args);
     const auto a = std::make_pair("-a", ArgsManager::ALLOW_ANY);
     const auto b = std::make_pair("-b", ArgsManager::ALLOW_ANY);
     const auto ccc = std::make_pair("-ccc", ArgsManager::ALLOW_ANY);
     const auto d = std::make_pair("-d", ArgsManager::ALLOW_ANY);
     const auto e = std::make_pair("-e", ArgsManager::ALLOW_ANY);
     const auto fff = std::make_pair("-fff", ArgsManager::ALLOW_ANY);
     const auto ggg = std::make_pair("-ggg", ArgsManager::ALLOW_ANY);
     const auto h = std::make_pair("-h", ArgsManager::ALLOW_ANY);
     const auto i = std::make_pair("-i", ArgsManager::ALLOW_ANY);
     const auto iii = std::make_pair("-iii", ArgsManager::ALLOW_ANY);
     test_args.SetupArgs({a, b, ccc, d, e, fff, ggg, h, i, iii});
 
     test_args.ReadConfigString(str_config);
     // expectation: a, b, ccc, d, fff, ggg, h, i end up in map
     // so do sec1.ccc, sec1.d, sec1.h, sec2.ccc, sec2.iii
 
     BOOST_CHECK(test_args.m_settings.command_line_options.empty());
     BOOST_CHECK(test_args.m_settings.ro_config.size() == 3);
     BOOST_CHECK(test_args.m_settings.ro_config[""].size() == 8);
     BOOST_CHECK(test_args.m_settings.ro_config["sec1"].size() == 3);
     BOOST_CHECK(test_args.m_settings.ro_config["sec2"].size() == 2);
 
     BOOST_CHECK(test_args.m_settings.ro_config[""].count("a") &&
                 test_args.m_settings.ro_config[""].count("b") &&
                 test_args.m_settings.ro_config[""].count("ccc") &&
                 test_args.m_settings.ro_config[""].count("d") &&
                 test_args.m_settings.ro_config[""].count("fff") &&
                 test_args.m_settings.ro_config[""].count("ggg") &&
                 test_args.m_settings.ro_config[""].count("h") &&
                 test_args.m_settings.ro_config[""].count("i"));
     BOOST_CHECK(test_args.m_settings.ro_config["sec1"].count("ccc") &&
                 test_args.m_settings.ro_config["sec1"].count("h") &&
                 test_args.m_settings.ro_config["sec2"].count("ccc") &&
                 test_args.m_settings.ro_config["sec2"].count("iii"));
 
     BOOST_CHECK(test_args.IsArgSet("-a") && test_args.IsArgSet("-b") &&
                 test_args.IsArgSet("-ccc") && test_args.IsArgSet("-d") &&
                 test_args.IsArgSet("-fff") && test_args.IsArgSet("-ggg") &&
                 test_args.IsArgSet("-h") && test_args.IsArgSet("-i") &&
                 !test_args.IsArgSet("-zzz") && !test_args.IsArgSet("-iii"));
 
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-ccc", "xxx") == "argument" &&
                 test_args.GetArg("-d", "xxx") == "e" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-h", "xxx") == "0" &&
                 test_args.GetArg("-i", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-iii", "xxx") == "xxx");
 
     for (const bool def : {false, true}) {
         BOOST_CHECK(test_args.GetBoolArg("-a", def) &&
                     test_args.GetBoolArg("-b", def) &&
                     !test_args.GetBoolArg("-ccc", def) &&
                     !test_args.GetBoolArg("-d", def) &&
                     !test_args.GetBoolArg("-fff", def) &&
                     test_args.GetBoolArg("-ggg", def) &&
                     !test_args.GetBoolArg("-h", def) &&
                     test_args.GetBoolArg("-i", def) &&
                     test_args.GetBoolArg("-zzz", def) == def &&
                     test_args.GetBoolArg("-iii", def) == def);
     }
 
     BOOST_CHECK(test_args.GetArgs("-a").size() == 1 &&
                 test_args.GetArgs("-a").front() == "");
     BOOST_CHECK(test_args.GetArgs("-b").size() == 1 &&
                 test_args.GetArgs("-b").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2 &&
                 test_args.GetArgs("-ccc").front() == "argument" &&
                 test_args.GetArgs("-ccc").back() == "multiple");
     BOOST_CHECK(test_args.GetArgs("-fff").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-nofff").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-ggg").size() == 1 &&
                 test_args.GetArgs("-ggg").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-noggg").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-h").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-noh").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-i").size() == 1 &&
                 test_args.GetArgs("-i").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-noi").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-zzz").size() == 0);
 
     BOOST_CHECK(!test_args.IsArgNegated("-a"));
     BOOST_CHECK(!test_args.IsArgNegated("-b"));
     BOOST_CHECK(!test_args.IsArgNegated("-ccc"));
     BOOST_CHECK(!test_args.IsArgNegated("-d"));
     BOOST_CHECK(test_args.IsArgNegated("-fff"));
     BOOST_CHECK(!test_args.IsArgNegated("-ggg"));
     // last setting takes precedence
     BOOST_CHECK(test_args.IsArgNegated("-h"));
     // last setting takes precedence
     BOOST_CHECK(!test_args.IsArgNegated("-i"));
     BOOST_CHECK(!test_args.IsArgNegated("-zzz"));
 
     // Test sections work
     test_args.SelectConfigNetwork("sec1");
 
     // same as original
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-iii", "xxx") == "xxx");
     // d is overridden
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "eee");
     // section-specific setting
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "1");
     // section takes priority for multiple values
     BOOST_CHECK(test_args.GetArg("-ccc", "xxx") == "extend1");
     // check multiple values works
     const std::vector<std::string> sec1_ccc_expected = {"extend1", "extend2",
                                                         "argument", "multiple"};
     const auto &sec1_ccc_res = test_args.GetArgs("-ccc");
     BOOST_CHECK_EQUAL_COLLECTIONS(sec1_ccc_res.begin(), sec1_ccc_res.end(),
                                   sec1_ccc_expected.begin(),
                                   sec1_ccc_expected.end());
 
     test_args.SelectConfigNetwork("sec2");
 
     // same as original
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-d", "xxx") == "e" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-h", "xxx") == "0");
     // section-specific setting
     BOOST_CHECK(test_args.GetArg("-iii", "xxx") == "2");
     // section takes priority for multiple values
     BOOST_CHECK(test_args.GetArg("-ccc", "xxx") == "extend3");
     // check multiple values works
     const std::vector<std::string> sec2_ccc_expected = {"extend3", "argument",
                                                         "multiple"};
     const auto &sec2_ccc_res = test_args.GetArgs("-ccc");
     BOOST_CHECK_EQUAL_COLLECTIONS(sec2_ccc_res.begin(), sec2_ccc_res.end(),
                                   sec2_ccc_expected.begin(),
                                   sec2_ccc_expected.end());
 
     // Test section only options
 
     test_args.SetNetworkOnlyArg("-d");
     test_args.SetNetworkOnlyArg("-ccc");
     test_args.SetNetworkOnlyArg("-h");
 
     test_args.SelectConfigNetwork(CBaseChainParams::MAIN);
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "e");
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "0");
 
     test_args.SelectConfigNetwork("sec1");
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "eee");
     BOOST_CHECK(test_args.GetArgs("-d").size() == 1);
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "1");
 
     test_args.SelectConfigNetwork("sec2");
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "xxx");
     BOOST_CHECK(test_args.GetArgs("-d").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 1);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "0");
 }
 
 BOOST_AUTO_TEST_CASE(util_GetArg) {
     TestArgsManager testArgs;
     LOCK(testArgs.cs_args);
     testArgs.m_settings.command_line_options.clear();
     testArgs.m_settings.command_line_options["strtest1"] = {"string..."};
     // strtest2 undefined on purpose
     testArgs.m_settings.command_line_options["inttest1"] = {"12345"};
     testArgs.m_settings.command_line_options["inttest2"] = {
         "81985529216486895"};
     // inttest3 undefined on purpose
     testArgs.m_settings.command_line_options["booltest1"] = {""};
     // booltest2 undefined on purpose
     testArgs.m_settings.command_line_options["booltest3"] = {"0"};
     testArgs.m_settings.command_line_options["booltest4"] = {"1"};
 
     // priorities
     testArgs.m_settings.command_line_options["pritest1"] = {"a", "b"};
     testArgs.m_settings.ro_config[""]["pritest2"] = {"a", "b"};
     testArgs.m_settings.command_line_options["pritest3"] = {"a"};
     testArgs.m_settings.ro_config[""]["pritest3"] = {"b"};
     testArgs.m_settings.command_line_options["pritest4"] = {"a", "b"};
     testArgs.m_settings.ro_config[""]["pritest4"] = {"c", "d"};
 
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest1", -1), 12345);
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest2", -1), 81985529216486895LL);
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest3", -1), -1);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest2", false), false);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest3", false), false);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest4", false), true);
 
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest1", "default"), "b");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest2", "default"), "a");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest3", "default"), "a");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest4", "default"), "b");
 }
 
 BOOST_AUTO_TEST_CASE(util_ClearForcedArg) {
     TestArgsManager testArgs;
     LOCK(testArgs.cs_args);
 
     // Clear command line arg
     testArgs.m_settings.command_line_options["cmdarg"] = {"cmdval"};
     BOOST_CHECK_EQUAL(testArgs.GetArg("cmdarg", "default"), "cmdval");
     testArgs.ClearForcedArg("cmdarg");
     BOOST_CHECK_EQUAL(testArgs.GetArg("cmdarg", "default"), "cmdval");
 
     // Clear config arg
     testArgs.m_settings.ro_config[""]["configarg"] = {"configval"};
     BOOST_CHECK_EQUAL(testArgs.GetArg("configarg", "default"), "configval");
     testArgs.ClearForcedArg("configarg");
     BOOST_CHECK_EQUAL(testArgs.GetArg("configarg", "default"), "configval");
 
     // Clear forced arg
     testArgs.m_settings.forced_settings["forcedarg"] = {"forcedval"};
     BOOST_CHECK_EQUAL(testArgs.GetArg("forcedarg", "default"), "forcedval");
     testArgs.ClearForcedArg("forcedarg");
     BOOST_CHECK_EQUAL(testArgs.GetArg("forcedarg", "default"), "default");
 }
 
 BOOST_AUTO_TEST_CASE(util_SetArg) {
     TestArgsManager testArgs;
 
     // SoftSetArg
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "string..."), true);
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest1").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest1").front(), "string...");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "...gnirts"), false);
     testArgs.ClearForcedArg("strtest1");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "...gnirts"), true);
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "...gnirts");
 
     // SoftSetBoolArg
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), false);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", true), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", false), false);
     testArgs.ClearForcedArg("booltest1");
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", true), true);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", true), false);
 
     // ForceSetArg
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     testArgs.ForceSetArg("strtest2", "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     testArgs.ForceSetArg("strtest2", "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "...gnirts");
 
     // ForceSetMultiArg
     testArgs.ForceSetMultiArg("strtest2", {"string...", "...gnirts"});
     BOOST_CHECK_THROW(testArgs.GetArg("strtest2", "default"),
                       std::runtime_error);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 2);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").back(), "...gnirts");
     testArgs.ClearForcedArg("strtest2");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 0);
 
     // If there are multi args, ForceSetArg should erase them
     testArgs.ForceSetMultiArg("strtest2", {"string..."});
     BOOST_CHECK_THROW(testArgs.GetArg("strtest2", "default"),
                       std::runtime_error);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     testArgs.ForceSetArg("strtest2", "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "...gnirts");
 }
 
 BOOST_AUTO_TEST_CASE(util_GetChainName) {
     TestArgsManager test_args;
     const auto testnet = std::make_pair("-testnet", ArgsManager::ALLOW_ANY);
     const auto regtest = std::make_pair("-regtest", ArgsManager::ALLOW_ANY);
     test_args.SetupArgs({testnet, regtest});
 
     const char *argv_testnet[] = {"cmd", "-testnet"};
     const char *argv_regtest[] = {"cmd", "-regtest"};
     const char *argv_test_no_reg[] = {"cmd", "-testnet", "-noregtest"};
     const char *argv_both[] = {"cmd", "-testnet", "-regtest"};
 
     // equivalent to "-testnet"
     // regtest in testnet section is ignored
     const char *testnetconf = "testnet=1\nregtest=0\n[test]\nregtest=1";
     std::string error;
 
     BOOST_CHECK(test_args.ParseParameters(0, (char **)argv_testnet, error));
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "main");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_testnet, error));
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_regtest, error));
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "regtest");
 
     BOOST_CHECK(test_args.ParseParameters(3, (char **)argv_test_no_reg, error));
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(3, (char **)argv_both, error));
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
     BOOST_CHECK(test_args.ParseParameters(0, (char **)argv_testnet, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_testnet, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_regtest, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
     BOOST_CHECK(test_args.ParseParameters(3, (char **)argv_test_no_reg, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(3, (char **)argv_both, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
     // check setting the network to test (and thus making
     // [test] regtest=1 potentially relevant) doesn't break things
     test_args.SelectConfigNetwork("test");
 
     BOOST_CHECK(test_args.ParseParameters(0, (char **)argv_testnet, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_testnet, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_regtest, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
     BOOST_CHECK(test_args.ParseParameters(2, (char **)argv_test_no_reg, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
     BOOST_CHECK(test_args.ParseParameters(3, (char **)argv_both, error));
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 }
 
 // Test different ways settings can be merged, and verify results. This test can
 // be used to confirm that updates to settings code don't change behavior
 // unintentionally.
 //
 // The test covers:
 //
 // - Combining different setting actions. Possible actions are: configuring a
 //   setting, negating a setting (adding "-no" prefix), and configuring/negating
 //   settings in a network section (adding "main." or "test." prefixes).
 //
 // - Combining settings from command line arguments and a config file.
 //
 // - Combining SoftSet and ForceSet calls.
 //
 // - Testing "main" and "test" network values to make sure settings from network
 //   sections are applied and to check for mainnet-specific behaviors like
 //   inheriting settings from the default section.
 //
 // - Testing network-specific settings like "-wallet", that may be ignored
 //   outside a network section, and non-network specific settings like "-server"
 //   that aren't sensitive to the network.
 //
 struct ArgsMergeTestingSetup : public BasicTestingSetup {
     //! Max number of actions to sequence together. Can decrease this when
     //! debugging to make test results easier to understand.
     static constexpr int MAX_ACTIONS = 3;
 
     enum Action { NONE, SET, NEGATE, SECTION_SET, SECTION_NEGATE };
     using ActionList = Action[MAX_ACTIONS];
 
     //! Enumerate all possible test configurations.
     template <typename Fn> void ForEachMergeSetup(Fn &&fn) {
         ActionList arg_actions = {};
         ForEachNoDup(arg_actions, SET, SECTION_NEGATE, [&] {
             ActionList conf_actions = {};
             ForEachNoDup(conf_actions, SET, SECTION_NEGATE, [&] {
                 for (bool soft_set : {false, true}) {
                     for (bool force_set : {false, true}) {
                         for (const std::string &section :
                              {CBaseChainParams::MAIN,
                               CBaseChainParams::TESTNET}) {
                             for (const std::string &network :
                                  {CBaseChainParams::MAIN,
                                   CBaseChainParams::TESTNET}) {
                                 for (bool net_specific : {false, true}) {
                                     fn(arg_actions, conf_actions, soft_set,
                                        force_set, section, network,
                                        net_specific);
                                 }
                             }
                         }
                     }
                 }
             });
         });
     }
 
     //! Translate actions into a list of <key>=<value> setting strings.
     std::vector<std::string> GetValues(const ActionList &actions,
                                        const std::string &section,
                                        const std::string &name,
                                        const std::string &value_prefix) {
         std::vector<std::string> values;
         int suffix = 0;
         for (Action action : actions) {
             if (action == NONE) {
                 break;
             }
             std::string prefix;
             if (action == SECTION_SET || action == SECTION_NEGATE) {
                 prefix = section + ".";
             }
             if (action == SET || action == SECTION_SET) {
                 for (int i = 0; i < 2; ++i) {
                     values.push_back(prefix + name + "=" + value_prefix +
                                      std::to_string(++suffix));
                 }
             }
             if (action == NEGATE || action == SECTION_NEGATE) {
                 values.push_back(prefix + "no" + name + "=1");
             }
         }
         return values;
     }
 };
 
 // Regression test covering different ways config settings can be merged. The
 // test parses and merges settings, representing the results as strings that get
 // compared against an expected hash. To debug, the result strings can be dumped
 // to a file (see comments below).
 BOOST_FIXTURE_TEST_CASE(util_ArgsMerge, ArgsMergeTestingSetup) {
     CHash256 out_sha;
     FILE *out_file = nullptr;
     if (const char *out_path = getenv("ARGS_MERGE_TEST_OUT")) {
         out_file = fsbridge::fopen(out_path, "w");
         if (!out_file) {
             throw std::system_error(errno, std::generic_category(),
                                     "fopen failed");
         }
     }
 
     ForEachMergeSetup([&](const ActionList &arg_actions,
                           const ActionList &conf_actions, bool soft_set,
                           bool force_set, const std::string &section,
                           const std::string &network, bool net_specific) {
         TestArgsManager parser;
         LOCK(parser.cs_args);
 
         std::string desc = "net=";
         desc += network;
         parser.m_network = network;
 
         const std::string &name = net_specific ? "wallet" : "server";
         const std::string key = "-" + name;
         parser.AddArg(key, name, ArgsManager::ALLOW_ANY,
                       OptionsCategory::OPTIONS);
         if (net_specific) {
             parser.SetNetworkOnlyArg(key);
         }
 
         auto args = GetValues(arg_actions, section, name, "a");
         std::vector<const char *> argv = {"ignored"};
         for (auto &arg : args) {
             arg.insert(0, "-");
             desc += " ";
             desc += arg;
             argv.push_back(arg.c_str());
         }
         std::string error;
         BOOST_CHECK(parser.ParseParameters(argv.size(), argv.data(), error));
         BOOST_CHECK_EQUAL(error, "");
 
         std::string conf;
         for (auto &conf_val : GetValues(conf_actions, section, name, "c")) {
             desc += " ";
             desc += conf_val;
             conf += conf_val;
             conf += "\n";
         }
         std::istringstream conf_stream(conf);
         BOOST_CHECK(parser.ReadConfigStream(conf_stream, "filepath", error));
         BOOST_CHECK_EQUAL(error, "");
 
         if (soft_set) {
             desc += " soft";
             parser.SoftSetArg(key, "soft1");
             parser.SoftSetArg(key, "soft2");
         }
 
         if (force_set) {
             desc += " force";
             parser.ForceSetArg(key, "force1");
             parser.ForceSetArg(key, "force2");
         }
 
         desc += " || ";
 
         if (!parser.IsArgSet(key)) {
             desc += "unset";
             BOOST_CHECK(!parser.IsArgNegated(key));
             BOOST_CHECK_EQUAL(parser.GetArg(key, "default"), "default");
             BOOST_CHECK(parser.GetArgs(key).empty());
         } else if (parser.IsArgNegated(key)) {
             desc += "negated";
             BOOST_CHECK_EQUAL(parser.GetArg(key, "default"), "0");
             BOOST_CHECK(parser.GetArgs(key).empty());
         } else {
             desc += parser.GetArg(key, "default");
             desc += " |";
             for (const auto &arg : parser.GetArgs(key)) {
                 desc += " ";
                 desc += arg;
             }
         }
 
         std::set<std::string> ignored = parser.GetUnsuitableSectionOnlyArgs();
         if (!ignored.empty()) {
             desc += " | ignored";
             for (const auto &arg : ignored) {
                 desc += " ";
                 desc += arg;
             }
         }
 
         desc += "\n";
 
         out_sha.Write((const uint8_t *)desc.data(), desc.size());
         if (out_file) {
             BOOST_REQUIRE(fwrite(desc.data(), 1, desc.size(), out_file) ==
                           desc.size());
         }
     });
 
     if (out_file) {
         if (fclose(out_file)) {
             throw std::system_error(errno, std::generic_category(),
                                     "fclose failed");
         }
         out_file = nullptr;
     }
 
     uint8_t out_sha_bytes[CSHA256::OUTPUT_SIZE];
     out_sha.Finalize(out_sha_bytes);
     std::string out_sha_hex =
         HexStr(std::begin(out_sha_bytes), std::end(out_sha_bytes));
 
     // If check below fails, should manually dump the results with:
     //
     //   ARGS_MERGE_TEST_OUT=results.txt ./test_bitcoin
     //   --run_test=util_tests/util_ArgsMerge
     //
     // And verify diff against previous results to make sure the changes are
     // expected.
     //
     // Results file is formatted like:
     //
     //   <input> || <IsArgSet/IsArgNegated/GetArg output> | <GetArgs output> |
     //   <GetUnsuitable output>
     BOOST_CHECK_EQUAL(
         out_sha_hex,
         "b835eef5977d69114eb039a976201f8c7121f34fe2b7ea2b73cafb516e5c9dc8");
 }
 
 // Similar test as above, but for ArgsManager::GetChainName function.
 struct ChainMergeTestingSetup : public BasicTestingSetup {
     static constexpr int MAX_ACTIONS = 2;
 
     enum Action {
         NONE,
         ENABLE_TEST,
         DISABLE_TEST,
         NEGATE_TEST,
         ENABLE_REG,
         DISABLE_REG,
         NEGATE_REG
     };
     using ActionList = Action[MAX_ACTIONS];
 
     //! Enumerate all possible test configurations.
     template <typename Fn> void ForEachMergeSetup(Fn &&fn) {
         ActionList arg_actions = {};
         ForEachNoDup(arg_actions, ENABLE_TEST, NEGATE_REG, [&] {
             ActionList conf_actions = {};
             ForEachNoDup(conf_actions, ENABLE_TEST, NEGATE_REG,
                          [&] { fn(arg_actions, conf_actions); });
         });
     }
 };
 
 BOOST_FIXTURE_TEST_CASE(util_ChainMerge, ChainMergeTestingSetup) {
     CHash256 out_sha;
     FILE *out_file = nullptr;
     if (const char *out_path = getenv("CHAIN_MERGE_TEST_OUT")) {
         out_file = fsbridge::fopen(out_path, "w");
         if (!out_file) {
             throw std::system_error(errno, std::generic_category(),
                                     "fopen failed");
         }
     }
 
     ForEachMergeSetup([&](const ActionList &arg_actions,
                           const ActionList &conf_actions) {
         TestArgsManager parser;
         LOCK(parser.cs_args);
         parser.AddArg("-regtest", "regtest", ArgsManager::ALLOW_ANY,
                       OptionsCategory::OPTIONS);
         parser.AddArg("-testnet", "testnet", ArgsManager::ALLOW_ANY,
                       OptionsCategory::OPTIONS);
 
         auto arg = [](Action action) -> const char * {
             switch (action) {
                 case ENABLE_TEST:
                     return "-testnet=1";
                 case DISABLE_TEST:
                     return "-testnet=0";
                 case NEGATE_TEST:
                     return "-notestnet=1";
                 case ENABLE_REG:
                     return "-regtest=1";
                 case DISABLE_REG:
                     return "-regtest=0";
                 case NEGATE_REG:
                     return "-noregtest=1";
                 default:
                     return nullptr;
             }
         };
 
         std::string desc;
         std::vector<const char *> argv = {"ignored"};
         for (Action action : arg_actions) {
             const char *argstr = arg(action);
             if (!argstr) {
                 break;
             }
             argv.push_back(argstr);
             desc += " ";
             desc += argv.back();
         }
         std::string error;
         BOOST_CHECK(parser.ParseParameters(argv.size(), argv.data(), error));
         BOOST_CHECK_EQUAL(error, "");
 
         std::string conf;
         for (Action action : conf_actions) {
             const char *argstr = arg(action);
             if (!argstr) {
                 break;
             }
             desc += " ";
             desc += argstr + 1;
             conf += argstr + 1;
         }
         std::istringstream conf_stream(conf);
         BOOST_CHECK(parser.ReadConfigStream(conf_stream, "filepath", error));
         BOOST_CHECK_EQUAL(error, "");
 
         desc += " || ";
         try {
             desc += parser.GetChainName();
         } catch (const std::runtime_error &e) {
             desc += "error: ";
             desc += e.what();
         }
         desc += "\n";
 
         out_sha.Write((const uint8_t *)desc.data(), desc.size());
         if (out_file) {
             BOOST_REQUIRE(fwrite(desc.data(), 1, desc.size(), out_file) ==
                           desc.size());
         }
     });
 
     if (out_file) {
         if (fclose(out_file)) {
             throw std::system_error(errno, std::generic_category(),
                                     "fclose failed");
         }
         out_file = nullptr;
     }
 
     uint8_t out_sha_bytes[CSHA256::OUTPUT_SIZE];
     out_sha.Finalize(out_sha_bytes);
     std::string out_sha_hex =
         HexStr(std::begin(out_sha_bytes), std::end(out_sha_bytes));
 
     // If check below fails, should manually dump the results with:
     //
     //   CHAIN_MERGE_TEST_OUT=results.txt ./test_bitcoin
     //   --run_test=util_tests/util_ChainMerge
     //
     // And verify diff against previous results to make sure the changes are
     // expected.
     //
     // Results file is formatted like:
     //
     //   <input> || <output>
     BOOST_CHECK_EQUAL(
         out_sha_hex,
         "94b4ad55c8ac639a56b93e36f7e32e4c611fd7d7dd7b2be6a71707b1eadcaec7");
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatMoney) {
     BOOST_CHECK_EQUAL(FormatMoney(Amount::zero()), "0.00");
     BOOST_CHECK_EQUAL(FormatMoney(123456789 * (COIN / 10000)), "12345.6789");
     BOOST_CHECK_EQUAL(FormatMoney(-1 * COIN), "-1.00");
 
     BOOST_CHECK_EQUAL(FormatMoney(100000000 * COIN), "100000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(10000000 * COIN), "10000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(1000000 * COIN), "1000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(100000 * COIN), "100000.00");
     BOOST_CHECK_EQUAL(FormatMoney(10000 * COIN), "10000.00");
     BOOST_CHECK_EQUAL(FormatMoney(1000 * COIN), "1000.00");
     BOOST_CHECK_EQUAL(FormatMoney(100 * COIN), "100.00");
     BOOST_CHECK_EQUAL(FormatMoney(10 * COIN), "10.00");
     BOOST_CHECK_EQUAL(FormatMoney(COIN), "1.00");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10), "0.10");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100), "0.01");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 1000), "0.001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10000), "0.0001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100000), "0.00001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 1000000), "0.000001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10000000), "0.0000001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100000000), "0.00000001");
 }
 
 BOOST_AUTO_TEST_CASE(util_ParseMoney) {
     Amount ret = Amount::zero();
     BOOST_CHECK(ParseMoney("0.0", ret));
     BOOST_CHECK_EQUAL(ret, Amount::zero());
 
     BOOST_CHECK(ParseMoney("12345.6789", ret));
     BOOST_CHECK_EQUAL(ret, 123456789 * (COIN / 10000));
 
     BOOST_CHECK(ParseMoney("100000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 100000000 * COIN);
     BOOST_CHECK(ParseMoney("10000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 10000000 * COIN);
     BOOST_CHECK(ParseMoney("1000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 1000000 * COIN);
     BOOST_CHECK(ParseMoney("100000.00", ret));
     BOOST_CHECK_EQUAL(ret, 100000 * COIN);
     BOOST_CHECK(ParseMoney("10000.00", ret));
     BOOST_CHECK_EQUAL(ret, 10000 * COIN);
     BOOST_CHECK(ParseMoney("1000.00", ret));
     BOOST_CHECK_EQUAL(ret, 1000 * COIN);
     BOOST_CHECK(ParseMoney("100.00", ret));
     BOOST_CHECK_EQUAL(ret, 100 * COIN);
     BOOST_CHECK(ParseMoney("10.00", ret));
     BOOST_CHECK_EQUAL(ret, 10 * COIN);
     BOOST_CHECK(ParseMoney("1.00", ret));
     BOOST_CHECK_EQUAL(ret, COIN);
     BOOST_CHECK(ParseMoney("1", ret));
     BOOST_CHECK_EQUAL(ret, COIN);
     BOOST_CHECK(ParseMoney("0.1", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10);
     BOOST_CHECK(ParseMoney("0.01", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100);
     BOOST_CHECK(ParseMoney("0.001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 1000);
     BOOST_CHECK(ParseMoney("0.0001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10000);
     BOOST_CHECK(ParseMoney("0.00001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100000);
     BOOST_CHECK(ParseMoney("0.000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 1000000);
     BOOST_CHECK(ParseMoney("0.0000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10000000);
     BOOST_CHECK(ParseMoney("0.00000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100000000);
 
     // Attempted 63 bit overflow should fail
     BOOST_CHECK(!ParseMoney("92233720368.54775808", ret));
 
     // Parsing negative amounts must fail
     BOOST_CHECK(!ParseMoney("-1", ret));
 }
 
 BOOST_AUTO_TEST_CASE(util_IsHex) {
     BOOST_CHECK(IsHex("00"));
     BOOST_CHECK(IsHex("00112233445566778899aabbccddeeffAABBCCDDEEFF"));
     BOOST_CHECK(IsHex("ff"));
     BOOST_CHECK(IsHex("FF"));
 
     BOOST_CHECK(!IsHex(""));
     BOOST_CHECK(!IsHex("0"));
     BOOST_CHECK(!IsHex("a"));
     BOOST_CHECK(!IsHex("eleven"));
     BOOST_CHECK(!IsHex("00xx00"));
     BOOST_CHECK(!IsHex("0x0000"));
 }
 
 BOOST_AUTO_TEST_CASE(util_IsHexNumber) {
     BOOST_CHECK(IsHexNumber("0x0"));
     BOOST_CHECK(IsHexNumber("0"));
     BOOST_CHECK(IsHexNumber("0x10"));
     BOOST_CHECK(IsHexNumber("10"));
     BOOST_CHECK(IsHexNumber("0xff"));
     BOOST_CHECK(IsHexNumber("ff"));
     BOOST_CHECK(IsHexNumber("0xFfa"));
     BOOST_CHECK(IsHexNumber("Ffa"));
     BOOST_CHECK(IsHexNumber("0x00112233445566778899aabbccddeeffAABBCCDDEEFF"));
     BOOST_CHECK(IsHexNumber("00112233445566778899aabbccddeeffAABBCCDDEEFF"));
 
     BOOST_CHECK(!IsHexNumber(""));      // empty string not allowed
     BOOST_CHECK(!IsHexNumber("0x"));    // empty string after prefix not allowed
     BOOST_CHECK(!IsHexNumber("0x0 "));  // no spaces at end,
     BOOST_CHECK(!IsHexNumber(" 0x0"));  // or beginning,
     BOOST_CHECK(!IsHexNumber("0x 0"));  // or middle,
     BOOST_CHECK(!IsHexNumber(" "));     // etc.
     BOOST_CHECK(!IsHexNumber("0x0ga")); // invalid character
     BOOST_CHECK(!IsHexNumber("x0"));    // broken prefix
     BOOST_CHECK(!IsHexNumber("0x0x00")); // two prefixes not allowed
 }
 
 BOOST_AUTO_TEST_CASE(util_seed_insecure_rand) {
     SeedInsecureRand(true);
     for (int mod = 2; mod < 11; mod++) {
         int mask = 1;
         // Really rough binomial confidence approximation.
         int err =
             30 * 10000. / mod * sqrt((1. / mod * (1 - 1. / mod)) / 10000.);
         // mask is 2^ceil(log2(mod))-1
         while (mask < mod - 1) {
             mask = (mask << 1) + 1;
         }
 
         int count = 0;
         // How often does it get a zero from the uniform range [0,mod)?
         for (int i = 0; i < 10000; i++) {
             uint32_t rval;
             do {
                 rval = InsecureRand32() & mask;
             } while (rval >= uint32_t(mod));
             count += rval == 0;
         }
         BOOST_CHECK(count <= 10000 / mod + err);
         BOOST_CHECK(count >= 10000 / mod - err);
     }
 }
 
 BOOST_AUTO_TEST_CASE(util_TimingResistantEqual) {
     BOOST_CHECK(TimingResistantEqual(std::string(""), std::string("")));
     BOOST_CHECK(!TimingResistantEqual(std::string("abc"), std::string("")));
     BOOST_CHECK(!TimingResistantEqual(std::string(""), std::string("abc")));
     BOOST_CHECK(!TimingResistantEqual(std::string("a"), std::string("aa")));
     BOOST_CHECK(!TimingResistantEqual(std::string("aa"), std::string("a")));
     BOOST_CHECK(TimingResistantEqual(std::string("abc"), std::string("abc")));
     BOOST_CHECK(!TimingResistantEqual(std::string("abc"), std::string("aba")));
 }
 
 /* Test strprintf formatting directives.
  * Put a string before and after to ensure sanity of element sizes on stack. */
 #define B "check_prefix"
 #define E "check_postfix"
 BOOST_AUTO_TEST_CASE(strprintf_numbers) {
     int64_t s64t = -9223372036854775807LL;   /* signed 64 bit test value */
     uint64_t u64t = 18446744073709551615ULL; /* unsigned 64 bit test value */
     BOOST_CHECK(strprintf("%s %d %s", B, s64t, E) == B
                 " -9223372036854775807 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, u64t, E) == B
                 " 18446744073709551615 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, u64t, E) == B " ffffffffffffffff " E);
 
     size_t st = 12345678;    /* unsigned size_t test value */
     ssize_t sst = -12345678; /* signed size_t test value */
     BOOST_CHECK(strprintf("%s %d %s", B, sst, E) == B " -12345678 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, st, E) == B " 12345678 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, st, E) == B " bc614e " E);
 
     ptrdiff_t pt = 87654321;   /* positive ptrdiff_t test value */
     ptrdiff_t spt = -87654321; /* negative ptrdiff_t test value */
     BOOST_CHECK(strprintf("%s %d %s", B, spt, E) == B " -87654321 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, pt, E) == B " 87654321 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, pt, E) == B " 5397fb1 " E);
 }
 #undef B
 #undef E
 
 /* Check for mingw/wine issue #3494
  * Remove this test before time.ctime(0xffffffff) == 'Sun Feb  7 07:28:15 2106'
  */
 BOOST_AUTO_TEST_CASE(gettime) {
     BOOST_CHECK((GetTime() & ~0xFFFFFFFFLL) == 0);
 }
 
 BOOST_AUTO_TEST_CASE(util_time_GetTime) {
     SetMockTime(111);
     // Check that mock time does not change after a sleep
     for (const auto &num_sleep : {0, 1}) {
         MilliSleep(num_sleep);
         BOOST_CHECK_EQUAL(111, GetTime()); // Deprecated time getter
         BOOST_CHECK_EQUAL(111, GetTime<std::chrono::seconds>().count());
         BOOST_CHECK_EQUAL(111000, GetTime<std::chrono::milliseconds>().count());
         BOOST_CHECK_EQUAL(111000000,
                           GetTime<std::chrono::microseconds>().count());
     }
 
     SetMockTime(0);
     // Check that system time changes after a sleep
     const auto ms_0 = GetTime<std::chrono::milliseconds>();
     const auto us_0 = GetTime<std::chrono::microseconds>();
     MilliSleep(1);
     BOOST_CHECK(ms_0 < GetTime<std::chrono::milliseconds>());
     BOOST_CHECK(us_0 < GetTime<std::chrono::microseconds>());
 }
 
 BOOST_AUTO_TEST_CASE(test_IsDigit) {
     BOOST_CHECK_EQUAL(IsDigit('0'), true);
     BOOST_CHECK_EQUAL(IsDigit('1'), true);
     BOOST_CHECK_EQUAL(IsDigit('8'), true);
     BOOST_CHECK_EQUAL(IsDigit('9'), true);
 
     BOOST_CHECK_EQUAL(IsDigit('0' - 1), false);
     BOOST_CHECK_EQUAL(IsDigit('9' + 1), false);
     BOOST_CHECK_EQUAL(IsDigit(0), false);
     BOOST_CHECK_EQUAL(IsDigit(1), false);
     BOOST_CHECK_EQUAL(IsDigit(8), false);
     BOOST_CHECK_EQUAL(IsDigit(9), false);
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseInt32) {
     int32_t n;
     // Valid values
     BOOST_CHECK(ParseInt32("1234", nullptr));
     BOOST_CHECK(ParseInt32("0", &n) && n == 0);
     BOOST_CHECK(ParseInt32("1234", &n) && n == 1234);
     BOOST_CHECK(ParseInt32("01234", &n) && n == 1234); // no octal
     BOOST_CHECK(ParseInt32("2147483647", &n) && n == 2147483647);
     // (-2147483647 - 1) equals INT_MIN
     BOOST_CHECK(ParseInt32("-2147483648", &n) && n == (-2147483647 - 1));
     BOOST_CHECK(ParseInt32("-1234", &n) && n == -1234);
     // Invalid values
     BOOST_CHECK(!ParseInt32("", &n));
     BOOST_CHECK(!ParseInt32(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseInt32("1 ", &n));
     BOOST_CHECK(!ParseInt32("1a", &n));
     BOOST_CHECK(!ParseInt32("aap", &n));
     BOOST_CHECK(!ParseInt32("0x1", &n)); // no hex
     BOOST_CHECK(!ParseInt32("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseInt32(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseInt32("-2147483649", nullptr));
     BOOST_CHECK(!ParseInt32("2147483648", nullptr));
     BOOST_CHECK(!ParseInt32("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseInt32("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseInt64) {
     int64_t n;
     // Valid values
     BOOST_CHECK(ParseInt64("1234", nullptr));
     BOOST_CHECK(ParseInt64("0", &n) && n == 0LL);
     BOOST_CHECK(ParseInt64("1234", &n) && n == 1234LL);
     BOOST_CHECK(ParseInt64("01234", &n) && n == 1234LL); // no octal
     BOOST_CHECK(ParseInt64("2147483647", &n) && n == 2147483647LL);
     BOOST_CHECK(ParseInt64("-2147483648", &n) && n == -2147483648LL);
     BOOST_CHECK(ParseInt64("9223372036854775807", &n) &&
                 n == (int64_t)9223372036854775807);
     BOOST_CHECK(ParseInt64("-9223372036854775808", &n) &&
                 n == (int64_t)-9223372036854775807 - 1);
     BOOST_CHECK(ParseInt64("-1234", &n) && n == -1234LL);
     // Invalid values
     BOOST_CHECK(!ParseInt64("", &n));
     BOOST_CHECK(!ParseInt64(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseInt64("1 ", &n));
     BOOST_CHECK(!ParseInt64("1a", &n));
     BOOST_CHECK(!ParseInt64("aap", &n));
     BOOST_CHECK(!ParseInt64("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseInt64(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseInt64("-9223372036854775809", nullptr));
     BOOST_CHECK(!ParseInt64("9223372036854775808", nullptr));
     BOOST_CHECK(!ParseInt64("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseInt64("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseUInt32) {
     uint32_t n;
     // Valid values
     BOOST_CHECK(ParseUInt32("1234", nullptr));
     BOOST_CHECK(ParseUInt32("0", &n) && n == 0);
     BOOST_CHECK(ParseUInt32("1234", &n) && n == 1234);
     BOOST_CHECK(ParseUInt32("01234", &n) && n == 1234); // no octal
     BOOST_CHECK(ParseUInt32("2147483647", &n) && n == 2147483647);
     BOOST_CHECK(ParseUInt32("2147483648", &n) && n == (uint32_t)2147483648);
     BOOST_CHECK(ParseUInt32("4294967295", &n) && n == (uint32_t)4294967295);
     // Invalid values
     BOOST_CHECK(!ParseUInt32("", &n));
     BOOST_CHECK(!ParseUInt32(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseUInt32(" -1", &n));
     BOOST_CHECK(!ParseUInt32("1 ", &n));
     BOOST_CHECK(!ParseUInt32("1a", &n));
     BOOST_CHECK(!ParseUInt32("aap", &n));
     BOOST_CHECK(!ParseUInt32("0x1", &n)); // no hex
     BOOST_CHECK(!ParseUInt32("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseUInt32(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseUInt32("-2147483648", &n));
     BOOST_CHECK(!ParseUInt32("4294967296", &n));
     BOOST_CHECK(!ParseUInt32("-1234", &n));
     BOOST_CHECK(!ParseUInt32("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseUInt32("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseUInt64) {
     uint64_t n;
     // Valid values
     BOOST_CHECK(ParseUInt64("1234", nullptr));
     BOOST_CHECK(ParseUInt64("0", &n) && n == 0LL);
     BOOST_CHECK(ParseUInt64("1234", &n) && n == 1234LL);
     BOOST_CHECK(ParseUInt64("01234", &n) && n == 1234LL); // no octal
     BOOST_CHECK(ParseUInt64("2147483647", &n) && n == 2147483647LL);
     BOOST_CHECK(ParseUInt64("9223372036854775807", &n) &&
                 n == 9223372036854775807ULL);
     BOOST_CHECK(ParseUInt64("9223372036854775808", &n) &&
                 n == 9223372036854775808ULL);
     BOOST_CHECK(ParseUInt64("18446744073709551615", &n) &&
                 n == 18446744073709551615ULL);
     // Invalid values
     BOOST_CHECK(!ParseUInt64("", &n));
     BOOST_CHECK(!ParseUInt64(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseUInt64(" -1", &n));
     BOOST_CHECK(!ParseUInt64("1 ", &n));
     BOOST_CHECK(!ParseUInt64("1a", &n));
     BOOST_CHECK(!ParseUInt64("aap", &n));
     BOOST_CHECK(!ParseUInt64("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseUInt64(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseUInt64("-9223372036854775809", nullptr));
     BOOST_CHECK(!ParseUInt64("18446744073709551616", nullptr));
     BOOST_CHECK(!ParseUInt64("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseUInt64("-2147483648", &n));
     BOOST_CHECK(!ParseUInt64("-9223372036854775808", &n));
     BOOST_CHECK(!ParseUInt64("-1234", &n));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseDouble) {
     double n;
     // Valid values
     BOOST_CHECK(ParseDouble("1234", nullptr));
     BOOST_CHECK(ParseDouble("0", &n) && n == 0.0);
     BOOST_CHECK(ParseDouble("1234", &n) && n == 1234.0);
     BOOST_CHECK(ParseDouble("01234", &n) && n == 1234.0); // no octal
     BOOST_CHECK(ParseDouble("2147483647", &n) && n == 2147483647.0);
     BOOST_CHECK(ParseDouble("-2147483648", &n) && n == -2147483648.0);
     BOOST_CHECK(ParseDouble("-1234", &n) && n == -1234.0);
     BOOST_CHECK(ParseDouble("1e6", &n) && n == 1e6);
     BOOST_CHECK(ParseDouble("-1e6", &n) && n == -1e6);
     // Invalid values
     BOOST_CHECK(!ParseDouble("", &n));
     BOOST_CHECK(!ParseDouble(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseDouble("1 ", &n));
     BOOST_CHECK(!ParseDouble("1a", &n));
     BOOST_CHECK(!ParseDouble("aap", &n));
     BOOST_CHECK(!ParseDouble("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseDouble(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseDouble("-1e10000", nullptr));
     BOOST_CHECK(!ParseDouble("1e10000", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_FormatParagraph) {
     BOOST_CHECK_EQUAL(FormatParagraph("", 79, 0), "");
     BOOST_CHECK_EQUAL(FormatParagraph("test", 79, 0), "test");
     BOOST_CHECK_EQUAL(FormatParagraph(" test", 79, 0), " test");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 79, 0), "test test");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 4, 0), "test\ntest");
     BOOST_CHECK_EQUAL(FormatParagraph("testerde test", 4, 0), "testerde\ntest");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 4, 4), "test\n    test");
 
     // Make sure we don't indent a fully-new line following a too-long line
     // ending
     BOOST_CHECK_EQUAL(FormatParagraph("test test\nabc", 4, 4),
                       "test\n    test\nabc");
 
     BOOST_CHECK_EQUAL(
         FormatParagraph("This_is_a_very_long_test_string_without_any_spaces_so_"
                         "it_should_just_get_returned_as_is_despite_the_length "
                         "until it gets here",
                         79),
         "This_is_a_very_long_test_string_without_any_spaces_so_it_should_just_"
         "get_returned_as_is_despite_the_length\nuntil it gets here");
 
     // Test wrap length is exact
     BOOST_CHECK_EQUAL(
         FormatParagraph("a b c d e f g h i j k l m n o p q r s t u v w x y z 1 "
                         "2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p",
                         79),
         "a b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 8 9 "
         "a b c de\nf g h i j k l m n o p");
     BOOST_CHECK_EQUAL(
         FormatParagraph("x\na b c d e f g h i j k l m n o p q r s t u v w x y "
                         "z 1 2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p",
                         79),
         "x\na b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 "
         "8 9 a b c de\nf g h i j k l m n o p");
     // Indent should be included in length of lines
     BOOST_CHECK_EQUAL(
         FormatParagraph("x\na b c d e f g h i j k l m n o p q r s t u v w x y "
                         "z 1 2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p q "
                         "r s t u v w x y z 0 1 2 3 4 5 6 7 8 9 a b c d e fg h "
                         "i j k",
                         79, 4),
         "x\na b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 "
         "8 9 a b c de\n    f g h i j k l m n o p q r s t u v w x y z 0 1 2 3 4 "
         "5 6 7 8 9 a b c d e fg\n    h i j k");
 
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string. This is a second "
                         "sentence in the very long test string.",
                         79),
         "This is a very long test string. This is a second sentence in the "
         "very long\ntest string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string.\nThis is a second "
                         "sentence in the very long test string. This is a "
                         "third sentence in the very long test string.",
                         79),
         "This is a very long test string.\nThis is a second sentence in the "
         "very long test string. This is a third\nsentence in the very long "
         "test string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string.\n\nThis is a second "
                         "sentence in the very long test string. This is a "
                         "third sentence in the very long test string.",
                         79),
         "This is a very long test string.\n\nThis is a second sentence in the "
         "very long test string. This is a third\nsentence in the very long "
         "test string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph(
             "Testing that normal newlines do not get indented.\nLike here.",
             79),
         "Testing that normal newlines do not get indented.\nLike here.");
 }
 
 BOOST_AUTO_TEST_CASE(test_FormatSubVersion) {
     std::vector<std::string> comments;
     comments.push_back(std::string("comment1"));
     std::vector<std::string> comments2;
     comments2.push_back(std::string("comment1"));
     // Semicolon is discouraged but not forbidden by BIP-0014
     comments2.push_back(SanitizeString(
         std::string("Comment2; .,_?@-; !\"#$%&'()*+/<=>[]\\^`{|}~"),
         SAFE_CHARS_UA_COMMENT));
     BOOST_CHECK_EQUAL(
         FormatSubVersion("Test", 99900, std::vector<std::string>()),
         std::string("/Test:0.9.99/"));
     BOOST_CHECK_EQUAL(FormatSubVersion("Test", 99900, comments),
                       std::string("/Test:0.9.99(comment1)/"));
     BOOST_CHECK_EQUAL(
         FormatSubVersion("Test", 99900, comments2),
         std::string("/Test:0.9.99(comment1; Comment2; .,_?@-; )/"));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseFixedPoint) {
     int64_t amount = 0;
     BOOST_CHECK(ParseFixedPoint("0", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 0LL);
     BOOST_CHECK(ParseFixedPoint("1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000LL);
     BOOST_CHECK(ParseFixedPoint("0.0", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 0LL);
     BOOST_CHECK(ParseFixedPoint("-0.1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -10000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 110000000LL);
     BOOST_CHECK(ParseFixedPoint("1.10000000000000000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 110000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1e1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1100000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1e-1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 11000000LL);
     BOOST_CHECK(ParseFixedPoint("1000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000000LL);
     BOOST_CHECK(ParseFixedPoint("-1000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -100000000000LL);
     BOOST_CHECK(ParseFixedPoint("0.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1LL);
     BOOST_CHECK(ParseFixedPoint("0.0000000100000000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1LL);
     BOOST_CHECK(ParseFixedPoint("-0.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -1LL);
     BOOST_CHECK(ParseFixedPoint("1000000000.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000000000001LL);
     BOOST_CHECK(ParseFixedPoint("9999999999.99999999", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 999999999999999999LL);
     BOOST_CHECK(ParseFixedPoint("-9999999999.99999999", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -999999999999999999LL);
 
     BOOST_CHECK(!ParseFixedPoint("", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("a-1000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-a1000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-1000a", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-01000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("00.1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint(".1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("--0.1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("0.000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-0.000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("0.00000001000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000009", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000009", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-99999999999.99999999", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("99999909999.09999999", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("92233720368.54775807", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("92233720368.54775808", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-92233720368.54775808", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-92233720368.54775809", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.1e", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.1e-", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.", 8, &amount));
 }
 
 static void TestOtherThread(fs::path dirname, std::string lockname,
                             bool *result) {
     *result = LockDirectory(dirname, lockname);
 }
 
 #ifndef WIN32 // Cannot do this test on WIN32 due to lack of fork()
 static constexpr char LockCommand = 'L';
 static constexpr char UnlockCommand = 'U';
 static constexpr char ExitCommand = 'X';
 
 static void TestOtherProcess(fs::path dirname, std::string lockname, int fd) {
     char ch;
     while (true) {
         // Wait for command
         int rv = read(fd, &ch, 1);
         assert(rv == 1);
         switch (ch) {
             case LockCommand:
                 ch = LockDirectory(dirname, lockname);
                 rv = write(fd, &ch, 1);
                 assert(rv == 1);
                 break;
             case UnlockCommand:
                 ReleaseDirectoryLocks();
                 ch = true; // Always succeeds
                 rv = write(fd, &ch, 1);
                 assert(rv == 1);
                 break;
             case ExitCommand:
                 close(fd);
                 // As an alternative to exit() which runs the exit handlers
                 // (which seem to be flakey with Boost test suite with JUNIT
                 // logging in a forked process), just vanish this process as
                 // fast as possible. `quick_exit()` would also work, but it is
                 // not available on all non glibc platforms.
                 // Using exec also stops valgrind from thinking it needs to
                 // analyze the memory leaks in this forked process.
                 execlp("true", "true", (char *)NULL);
             default:
                 assert(0);
         }
     }
 }
 #endif
 
 BOOST_AUTO_TEST_CASE(test_LockDirectory) {
     fs::path dirname = GetDataDir() / "lock_dir";
     const std::string lockname = ".lock";
 #ifndef WIN32
     // Revert SIGCHLD to default, otherwise boost.test will catch and fail on
     // it: there is BOOST_TEST_IGNORE_SIGCHLD but that only works when defined
     // at build-time of the boost library
     void (*old_handler)(int) = signal(SIGCHLD, SIG_DFL);
 
     // Fork another process for testing before creating the lock, so that we
     // won't fork while holding the lock (which might be undefined, and is not
     // relevant as test case as that is avoided with -daemonize).
     int fd[2];
     BOOST_CHECK_EQUAL(socketpair(AF_UNIX, SOCK_STREAM, 0, fd), 0);
     pid_t pid = fork();
     if (!pid) {
         BOOST_CHECK_EQUAL(close(fd[1]), 0); // Child: close parent end
         TestOtherProcess(dirname, lockname, fd[0]);
     }
     BOOST_CHECK_EQUAL(close(fd[0]), 0); // Parent: close child end
 #endif
     // Lock on non-existent directory should fail
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), false);
 
     fs::create_directories(dirname);
 
     // Probing lock on new directory should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Persistent lock on new directory should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), true);
 
     // Another lock on the directory from the same thread should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), true);
 
     // Another lock on the directory from a different thread within the same
     // process should succeed
     bool threadresult;
     std::thread thr(TestOtherThread, dirname, lockname, &threadresult);
     thr.join();
     BOOST_CHECK_EQUAL(threadresult, true);
 #ifndef WIN32
     // Try to acquire lock in child process while we're holding it, this should
     // fail.
     char ch;
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, false);
 
     // Give up our lock
     ReleaseDirectoryLocks();
     // Probing lock from our side now should succeed, but not hold on to the
     // lock.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Try to acquire the lock in the child process, this should be successful.
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, true);
 
     // When we try to probe the lock now, it should fail.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), false);
 
     // Unlock the lock in the child process
     BOOST_CHECK_EQUAL(write(fd[1], &UnlockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, true);
 
     // When we try to probe the lock now, it should succeed.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Re-lock the lock in the child process, then wait for it to exit, check
     // successful return. After that, we check that exiting the process
     // has released the lock as we would expect by probing it.
     int processstatus;
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(write(fd[1], &ExitCommand, 1), 1);
     BOOST_CHECK_EQUAL(waitpid(pid, &processstatus, 0), pid);
     BOOST_CHECK_EQUAL(processstatus, 0);
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Restore SIGCHLD
     signal(SIGCHLD, old_handler);
     BOOST_CHECK_EQUAL(close(fd[1]), 0); // Close our side of the socketpair
 #endif
     // Clean up
     ReleaseDirectoryLocks();
     fs::remove_all(dirname);
 }
 
 BOOST_AUTO_TEST_CASE(test_DirIsWritable) {
     // Should be able to write to the data dir.
     fs::path tmpdirname = GetDataDir();
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), true);
 
     // Should not be able to write to a non-existent dir.
     tmpdirname = tmpdirname / fs::unique_path();
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), false);
 
     fs::create_directory(tmpdirname);
     // Should be able to write to it now.
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), true);
     fs::remove(tmpdirname);
 }
 
 template <int F, int T>
 static void CheckConvertBits(const std::vector<uint8_t> &in,
                              const std::vector<uint8_t> &expected) {
     std::vector<uint8_t> outpad;
     bool ret = ConvertBits<F, T, true>([&](uint8_t c) { outpad.push_back(c); },
                                        in.begin(), in.end());
     BOOST_CHECK(ret);
     BOOST_CHECK(outpad == expected);
 
     const bool dopad = (in.size() * F) % T;
     std::vector<uint8_t> outnopad;
     ret = ConvertBits<F, T, false>([&](uint8_t c) { outnopad.push_back(c); },
                                    in.begin(), in.end());
     BOOST_CHECK(ret != (dopad && !outpad.empty() && outpad.back()));
 
     if (dopad) {
         // We should have skipped the last digit.
         outnopad.push_back(expected.back());
     }
 
     BOOST_CHECK(outnopad == expected);
 
     // Check the other way around.
     // Check with padding. We may get an extra 0 in that case.
     std::vector<uint8_t> origpad;
     ret = ConvertBits<T, F, true>([&](uint8_t c) { origpad.push_back(c); },
                                   expected.begin(), expected.end());
     BOOST_CHECK(ret);
 
     std::vector<uint8_t> orignopad;
     ret = ConvertBits<T, F, false>([&](uint8_t c) { orignopad.push_back(c); },
                                    expected.begin(), expected.end());
     BOOST_CHECK(ret != ((expected.size() * T) % F && !origpad.empty() &&
                         origpad.back()));
     BOOST_CHECK(orignopad == in);
 
     if (dopad) {
         BOOST_CHECK_EQUAL(origpad.back(), 0);
         origpad.pop_back();
     }
 
     BOOST_CHECK(origpad == in);
 }
 
 BOOST_AUTO_TEST_CASE(test_ConvertBits) {
     CheckConvertBits<8, 5>({}, {});
     CheckConvertBits<8, 5>({0xff}, {0x1f, 0x1c});
     CheckConvertBits<8, 5>({0xff, 0xff}, {0x1f, 0x1f, 0x1f, 0x10});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff}, {0x1f, 0x1f, 0x1f, 0x1f, 0x1e});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x18});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef},
                            {0x00, 0x04, 0x11, 0x14, 0x0a, 0x19, 0x1c, 0x09,
                             0x15, 0x0f, 0x06, 0x1e, 0x1e});
     CheckConvertBits<8, 5>({0x00}, {0x00, 0x00});
     CheckConvertBits<8, 5>({0xf8}, {0x1f, 0x00});
     CheckConvertBits<8, 5>({0x00, 0x00}, {0x00, 0x00, 0x00, 0x00});
 }
 
 BOOST_AUTO_TEST_CASE(test_ToLower) {
     BOOST_CHECK_EQUAL(ToLower('@'), '@');
     BOOST_CHECK_EQUAL(ToLower('A'), 'a');
     BOOST_CHECK_EQUAL(ToLower('Z'), 'z');
     BOOST_CHECK_EQUAL(ToLower('['), '[');
     BOOST_CHECK_EQUAL(ToLower(0), 0);
     BOOST_CHECK_EQUAL(ToLower('\xff'), '\xff');
 
     BOOST_CHECK_EQUAL(ToLower(""), "");
     BOOST_CHECK_EQUAL(ToLower("#HODL"), "#hodl");
     BOOST_CHECK_EQUAL(ToLower("\x00\xfe\xff"), "\x00\xfe\xff");
 }
 
 BOOST_AUTO_TEST_CASE(test_ToUpper) {
     BOOST_CHECK_EQUAL(ToUpper('`'), '`');
     BOOST_CHECK_EQUAL(ToUpper('a'), 'A');
     BOOST_CHECK_EQUAL(ToUpper('z'), 'Z');
     BOOST_CHECK_EQUAL(ToUpper('{'), '{');
     BOOST_CHECK_EQUAL(ToUpper(0), 0);
     BOOST_CHECK_EQUAL(ToUpper('\xff'), '\xff');
 
     BOOST_CHECK_EQUAL(ToUpper(""), "");
     BOOST_CHECK_EQUAL(ToUpper("#hodl"), "#HODL");
     BOOST_CHECK_EQUAL(ToUpper("\x00\xfe\xff"), "\x00\xfe\xff");
 }
 
 BOOST_AUTO_TEST_CASE(test_Capitalize) {
     BOOST_CHECK_EQUAL(Capitalize(""), "");
     BOOST_CHECK_EQUAL(Capitalize("bitcoin"), "Bitcoin");
     BOOST_CHECK_EQUAL(Capitalize("\x00\xfe\xff"), "\x00\xfe\xff");
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/util/string.cpp b/src/util/string.cpp
new file mode 100644
index 000000000..8ea3a1afc
--- /dev/null
+++ b/src/util/string.cpp
@@ -0,0 +1,5 @@
+// Copyright (c) 2019 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 <util/string.h>
diff --git a/src/util/string.h b/src/util/string.h
new file mode 100644
index 000000000..ccbb778ed
--- /dev/null
+++ b/src/util/string.h
@@ -0,0 +1,37 @@
+// Copyright (c) 2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_UTIL_STRING_H
+#define BITCOIN_UTIL_STRING_H
+
+#include <functional>
+#include <string>
+#include <vector>
+
+/**
+ * Join a list of items
+ *
+ * @param list       The list to join
+ * @param separator  The separator
+ * @param unary_op   Apply this operator to each item in the list
+ */
+template <typename T, typename UnaryOp>
+std::string Join(const std::vector<T> &list, const std::string &separator,
+                 UnaryOp unary_op) {
+    std::string ret;
+    for (size_t i = 0; i < list.size(); ++i) {
+        if (i > 0) {
+            ret += separator;
+        }
+        ret += unary_op(list.at(i));
+    }
+    return ret;
+}
+
+inline std::string Join(const std::vector<std::string> &list,
+                        const std::string &separator) {
+    return Join(list, separator, [](const std::string &i) { return i; });
+}
+
+#endif // BITCOIN_UTIL_STRING_H