merge

Update README.md

CMakeLists.txt

@@ -1,14 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.2)
-
-if (${CMAKE_VERSION} VERSION_LESS 3.11)
-    cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
-else ()
-    cmake_policy(VERSION 3.11)
-endif ()
-
-enable_language(C)
+cmake_minimum_required(VERSION 3.10)
 
 # ---------------------------------------------------------------------------------------
 # Start spdlog project
@@ -36,13 +28,13 @@ endif ()
 if (NOT CMAKE_CXX_STANDARD)
     set(CMAKE_CXX_STANDARD 14)
     set(CMAKE_CXX_STANDARD_REQUIRED ON)
-endif ()
+endif()
 
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-if (CMAKE_SYSTEM_NAME MATCHES "CYGWIN")
+if (CMAKE_SYSTEM_NAME MATCHES "CYGWIN" OR CMAKE_SYSTEM_NAME MATCHES "MSYS")
     set(CMAKE_CXX_EXTENSIONS ON)
-endif ()
+endif()
 
 # ---------------------------------------------------------------------------------------
 # Set SPDLOG_MASTER_PROJECT to ON if we are building spdlog
@@ -85,38 +77,38 @@ option(SPDLOG_FMT_EXTERNAL "Use external fmt library instead of bundled" OFF)
 option(SPDLOG_FMT_EXTERNAL_HO "Use external fmt header-only library instead of bundled" OFF)
 option(SPDLOG_NO_EXCEPTIONS "Compile with -fno-exceptions. Call abort() on any spdlog exceptions" OFF)
 
-if (SPDLOG_FMT_EXTERNAL AND SPDLOG_FMT_EXTERNAL_HO)
+if(SPDLOG_FMT_EXTERNAL AND SPDLOG_FMT_EXTERNAL_HO)
     message(FATAL_ERROR "SPDLOG_FMT_EXTERNAL and SPDLOG_FMT_EXTERNAL_HO are mutually exclusive")
-endif ()
+endif()
 
 # misc tweakme options
-if (WIN32)
+if(WIN32)
     option(SPDLOG_WCHAR_SUPPORT "Support wchar api" OFF)
     option(SPDLOG_WCHAR_FILENAMES "Support wchar filenames" OFF)
-endif ()
-if (${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
+endif()
+if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
     option(SPDLOG_CLOCK_COARSE
-            "Use the much faster (but much less accurate) CLOCK_REALTIME_COARSE instead of the regular clock," OFF)
-endif ()
+           "Use the much faster (but much less accurate) CLOCK_REALTIME_COARSE instead of the regular clock," OFF)
+endif()
 
 option(SPDLOG_PREVENT_CHILD_FD "Prevent from child processes to inherit log file descriptors" OFF)
 option(SPDLOG_NO_THREAD_ID "prevent spdlog from querying the thread id on each log call if thread id is not needed" OFF)
 option(SPDLOG_NO_TLS "prevent spdlog from using thread local storage" OFF)
 option(
-        SPDLOG_NO_ATOMIC_LEVELS
-        "prevent spdlog from using of std::atomic log levels (use only if your code never modifies log levels concurrently"
-        OFF)
+    SPDLOG_NO_ATOMIC_LEVELS
+    "prevent spdlog from using of std::atomic log levels (use only if your code never modifies log levels concurrently"
+    OFF)
 
 # clang-tidy
-if (${CMAKE_VERSION} VERSION_GREATER "3.5")
+if(${CMAKE_VERSION} VERSION_GREATER "3.5")
     option(SPDLOG_TIDY "run clang-tidy" OFF)
-endif ()
+endif()
 
-if (SPDLOG_TIDY)
+if(SPDLOG_TIDY)
     set(CMAKE_CXX_CLANG_TIDY "clang-tidy")
     set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
     message(STATUS "Enabled clang-tidy")
-endif ()
+endif()
 
 find_package(Threads REQUIRED)
 message(STATUS "Build type: " ${CMAKE_BUILD_TYPE})
@@ -157,7 +149,7 @@ endif ()
 
 if (NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
     list(APPEND SPDLOG_SRCS src/fmt.cpp)
-endif ()
+endif()
 
 if (WIN32 AND SPDLOG_BUILD_SHARED)
     list(APPEND SPDLOG_SRCS ${CMAKE_CURRENT_BINARY_DIR}/version.rc)
@@ -172,45 +164,45 @@ if (SPDLOG_BUILD_SHARED)
     endif ()
     if (NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
         target_compile_definitions(spdlog PRIVATE FMT_EXPORT PUBLIC FMT_SHARED)
-    endif ()
-else ()
+    endif()
+else()
     add_library(spdlog STATIC ${SPDLOG_SRCS} ${SPDLOG_ALL_HEADERS})
-endif ()
+endif()
 
 add_library(spdlog::spdlog ALIAS spdlog)
 
 target_include_directories(spdlog PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
-        "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
+                                         "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
 target_link_libraries(spdlog PUBLIC Threads::Threads)
 spdlog_enable_warnings(spdlog)
 
 set_target_properties(spdlog PROPERTIES VERSION ${SPDLOG_VERSION} SOVERSION ${SPDLOG_VERSION_MAJOR})
 set_target_properties(spdlog PROPERTIES DEBUG_POSTFIX d)
 
-if (COMMAND target_precompile_headers AND SPDLOG_ENABLE_PCH)
+if(COMMAND target_precompile_headers AND SPDLOG_ENABLE_PCH)
     configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/pch.h.in ${PROJECT_BINARY_DIR}/spdlog_pch.h @ONLY)
     target_precompile_headers(spdlog PRIVATE ${PROJECT_BINARY_DIR}/spdlog_pch.h)
-endif ()
+endif()
 
 
 # ---------------------------------------------------------------------------------------
 # Use fmt package if using external fmt
 # ---------------------------------------------------------------------------------------
-if (SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
-    if (NOT TARGET fmt::fmt)
+if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
+    if(NOT TARGET fmt::fmt)
         find_package(fmt 5.3.0 REQUIRED)
-    endif ()
+    endif()
     target_compile_definitions(spdlog PUBLIC SPDLOG_FMT_EXTERNAL)
 
     # use external fmt-header-nly
-    if (SPDLOG_FMT_EXTERNAL_HO)
+    if(SPDLOG_FMT_EXTERNAL_HO)
         target_link_libraries(spdlog PUBLIC fmt::fmt-header-only)
-    else () # use external compile fmt
+    else() # use external compile fmt
         target_link_libraries(spdlog PUBLIC fmt::fmt)
-    endif ()
+    endif()
 
     set(PKG_CONFIG_REQUIRES fmt) # add dependency to pkg-config
-endif ()
+endif()
 
 # ---------------------------------------------------------------------------------------
 # Misc definitions according to tweak options
@@ -263,21 +255,21 @@ if (SPDLOG_BUILD_EXAMPLE OR SPDLOG_BUILD_EXAMPLE_HO OR SPDLOG_BUILD_ALL)
     endif ()
 endif ()
 
-if (SPDLOG_BUILD_TESTS OR SPDLOG_BUILD_TESTS_HO OR SPDLOG_BUILD_ALL)
+if(SPDLOG_BUILD_TESTS OR SPDLOG_BUILD_TESTS_HO OR SPDLOG_BUILD_ALL)
     message(STATUS "Generating tests")
     enable_testing()
     add_subdirectory(tests)
-endif ()
+endif()
 
-if (SPDLOG_BUILD_BENCH OR SPDLOG_BUILD_ALL)
+if(SPDLOG_BUILD_BENCH OR SPDLOG_BUILD_ALL)
     message(STATUS "Generating benchmarks")
     add_subdirectory(bench)
-endif ()
+endif()
 
 # ---------------------------------------------------------------------------------------
 # Install
 # ---------------------------------------------------------------------------------------
-if (SPDLOG_INSTALL)
+if(SPDLOG_INSTALL)
     message(STATUS "Generating install")
     set(project_config_in "${CMAKE_CURRENT_LIST_DIR}/cmake/spdlogConfig.cmake.in")
     set(project_config_out "${CMAKE_CURRENT_BINARY_DIR}/spdlogConfig.cmake")
@@ -298,10 +290,10 @@ if (SPDLOG_INSTALL)
             ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
             RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 
-    if (NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
+    if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
         install(DIRECTORY include/${PROJECT_NAME}/fmt/bundled/
                 DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${PROJECT_NAME}/fmt/bundled/")
-    endif ()
+    endif()
 
     # ---------------------------------------------------------------------------------------
     # Install pkg-config file
@@ -327,4 +319,4 @@ if (SPDLOG_INSTALL)
     # Support creation of installable packages
     # ---------------------------------------------------------------------------------------
     include(cmake/spdlogCPack.cmake)
-endif ()
+endif()

README.md

@@ -25,7 +25,7 @@ $ cmake .. && make -j
 * Homebrew: `brew install spdlog`
 * MacPorts: `sudo port install spdlog`
 * FreeBSD:  `cd /usr/ports/devel/spdlog/ && make install clean`
-* Fedora: `yum install spdlog`
+* Fedora: `dnf install spdlog`
 * Gentoo: `emerge dev-libs/spdlog`
 * Arch Linux: `pacman -S spdlog`
 * vcpkg: `vcpkg install spdlog`
@@ -150,6 +150,20 @@ spdlog::flush_every(std::chrono::seconds(3));
 
 ```
 
+---
+#### Stopwatch
+```c++
+// Stopwatch support for spdlog
+#include "spdlog/stopwatch.h"
+void stopwatch_example()
+{
+    spdlog::stopwatch sw;    
+    spdlog::debug("Elapsed {}", sw);
+    spdlog::debug("Elapsed {:.3}", sw);       
+}
+
+```
+
 ---
 #### Log binary data in hex
 ```c++
@@ -399,6 +413,6 @@ Documentation can be found in the [wiki](https://github.com/gabime/spdlog/wiki/1
 
 ---
 
-Thanks to [JetBrains](https://www.jetbrains.com/?from=spdlog) for donating licenses to their products to help developing **spdlog** <a href="https://www.jetbrains.com/?from=spdlog"><img src="logos/jetbrains-variant-4.svg" width="94" align="center" /></a>
+Thanks to [JetBrains](https://www.jetbrains.com/?from=spdlog) for donating product licenses to help develop **spdlog** <a href="https://www.jetbrains.com/?from=spdlog"><img src="logos/jetbrains-variant-4.svg" width="94" align="center" /></a>
 
 

bench/CMakeLists.txt

@@ -1,6 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.10)
 project(spdlog_bench CXX)
 
 if(NOT TARGET spdlog)

bench/async_bench.cpp

@@ -9,7 +9,7 @@
 #include "spdlog/spdlog.h"
 #include "spdlog/async.h"
 #include "spdlog/sinks/basic_file_sink.h"
-#include "spdlog/sinks/stdout_color_sinks.h"
+#include "spdlog/fmt/bundled/locale.h"
 
 #include "utils.h"
 #include <atomic>
@@ -48,14 +48,14 @@ int count_lines(const char *filename)
 
 void verify_file(const char *filename, int expected_count)
 {
-    spdlog::info("Verifying {} to contain {:n} line..", filename, expected_count);
+    spdlog::info("Verifying {} to contain {} line..", filename, expected_count);
     auto count = count_lines(filename);
     if (count != expected_count)
     {
-        spdlog::error("Test failed. {} has {:n} lines instead of {:n}", filename, count, expected_count);
+        spdlog::error("Test failed. {} has {} lines instead of {}", filename, count, expected_count);
         exit(1);
     }
-    spdlog::info("Line count OK ({:n})\n", count);
+    spdlog::info("Line count OK ({})\n", count);
 }
 
 #ifdef _MSC_VER
@@ -98,11 +98,12 @@ int main(int argc, char *argv[])
 
         auto slot_size = sizeof(spdlog::details::async_msg);
         spdlog::info("-------------------------------------------------");
-        spdlog::info("Messages     : {:n}", howmany);
-        spdlog::info("Threads      : {:n}", threads);
-        spdlog::info("Queue        : {:n} slots", queue_size);
-        spdlog::info("Queue memory : {:n} x {} = {:n} KB ", queue_size, slot_size, (queue_size * slot_size) / 1024);
-        spdlog::info("Total iters  : {:n}", iters);
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Messages     : {:L}", howmany));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Threads      : {:L}", threads));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Queue        : {:L} slots", queue_size));
+        spdlog::info(fmt::format(
+            std::locale("en_US.UTF-8"), "Queue memory : {:L} x {:L} = {:L} KB ", queue_size, slot_size, (queue_size * slot_size) / 1024));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Total iters  : {:L}", iters));
         spdlog::info("-------------------------------------------------");
 
         const char *filename = "logs/basic_async.log";
@@ -175,5 +176,5 @@ void bench_mt(int howmany, std::shared_ptr<spdlog::logger> logger, int thread_co
 
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
-    spdlog::info("Elapsed: {} secs\t {:n}/sec", delta_d, int(howmany / delta_d));
+    spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Elapsed: {} secs\t {:L}/sec", delta_d, int(howmany / delta_d)));
 }

bench/bench.cpp

@@ -11,6 +11,7 @@
 #include "spdlog/sinks/daily_file_sink.h"
 #include "spdlog/sinks/null_sink.h"
 #include "spdlog/sinks/rotating_file_sink.h"
+#include "spdlog/fmt/bundled/locale.h"
 
 #include "utils.h"
 #include <atomic>
@@ -32,7 +33,7 @@ static const int max_threads = 1000;
 void bench_threaded_logging(size_t threads, int iters)
 {
     spdlog::info("**************************************************************");
-    spdlog::info("Multi threaded: {:n} threads, {:n} messages", threads, iters);
+    spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Multi threaded: {:L} threads, {:L} messages", threads, iters));
     spdlog::info("**************************************************************");
 
     auto basic_mt = spdlog::basic_logger_mt("basic_mt", "logs/basic_mt.log", true);
@@ -54,7 +55,7 @@ void bench_threaded_logging(size_t threads, int iters)
 void bench_single_threaded(int iters)
 {
     spdlog::info("**************************************************************");
-    spdlog::info("Single threaded: {:n} messages", iters);
+    spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Single threaded: {} messages", iters));
     spdlog::info("**************************************************************");
 
     auto basic_st = spdlog::basic_logger_st("basic_st", "logs/basic_st.log", true);
@@ -124,7 +125,8 @@ void bench(int howmany, std::shared_ptr<spdlog::logger> log)
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
 
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info(
+        fmt::format(std::locale("en_US.UTF-8"), "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(), delta_d, int(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
@@ -154,7 +156,8 @@ void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, size_t thread_co
 
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info(
+        fmt::format(std::locale("en_US.UTF-8"), "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(), delta_d, int(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
@@ -177,7 +180,7 @@ void bench_default_api(int howmany, std::shared_ptr<spdlog::logger> log)
     auto delta_d = duration_cast<duration<double>>(delta).count();
     spdlog::drop(log->name());
     spdlog::set_default_logger(std::move(orig_default));
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16}/sec", log->name(), delta_d, int(howmany / delta_d));
 }
 
 void bench_c_string(int howmany, std::shared_ptr<spdlog::logger> log)
@@ -204,7 +207,7 @@ void bench_c_string(int howmany, std::shared_ptr<spdlog::logger> log)
     auto delta_d = duration_cast<duration<double>>(delta).count();
     spdlog::drop(log->name());
     spdlog::set_default_logger(std::move(orig_default));
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16}/sec", log->name(), delta_d, int(howmany / delta_d));
 }
 
 */

cmake/version.rc.in

@@ -1,5 +1,5 @@
 #define APSTUDIO_READONLY_SYMBOLS
-#include "winres.h"
+#include <windows.h>
 #undef APSTUDIO_READONLY_SYMBOLS
 
 LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US

example/CMakeLists.txt

@@ -1,6 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.2)
+cmake_minimum_required(VERSION 3.10)
 project(spdlog_examples CXX)
 
 if (NOT TARGET spdlog)

example/example.cpp

@@ -13,6 +13,7 @@ void rotating_example();
 void daily_example();
 void async_example();
 void binary_example();
+void stopwatch_example();
 void trace_example();
 void multi_sink_example();
 void user_defined_example();
@@ -60,6 +61,7 @@ int main(int, char *[])
         user_defined_example();
         err_handler_example();
         trace_example();
+        stopwatch_example();
         custom_flags_example();
 
         // Flush all *registered* loggers using a worker thread every 3 seconds.
@@ -181,6 +183,16 @@ void trace_example()
     SPDLOG_LOGGER_TRACE(logger, "another trace message");
 }
 
+// stopwatch example
+#include "spdlog/stopwatch.h"
+#include <thread>
+void stopwatch_example()
+{
+    spdlog::stopwatch sw;
+    std::this_thread::sleep_for(std::chrono::milliseconds(123));
+    spdlog::info("Stopwatch: {} seconds", sw);
+}
+
 // A logger with multiple sinks (stdout and file) - each with a different format and log level.
 void multi_sink_example()
 {

include/spdlog/cfg/argv.h

@@ -21,7 +21,7 @@ namespace spdlog {
 namespace cfg {
 
 // search for SPDLOG_LEVEL= in the args and use it to init the levels
-void load_argv_levels(int argc, const char **argv)
+inline void load_argv_levels(int argc, const char **argv)
 {
     const std::string spdlog_level_prefix = "SPDLOG_LEVEL=";
     for (int i = 1; i < argc; i++)
@@ -36,7 +36,7 @@ void load_argv_levels(int argc, const char **argv)
     }
 }
 
-void load_argv_levels(int argc, char **argv)
+inline void load_argv_levels(int argc, char **argv)
 {
     load_argv_levels(argc, const_cast<const char **>(argv));
 }

include/spdlog/cfg/env.h

@@ -25,7 +25,7 @@
 
 namespace spdlog {
 namespace cfg {
-void load_env_levels()
+inline void load_env_levels()
 {
     auto env_val = details::os::getenv("SPDLOG_LEVEL");
     auto levels = helpers::extract_levels(env_val);

include/spdlog/details/fmt_helper.h

@@ -34,7 +34,15 @@ template<typename T>
 inline unsigned int count_digits(T n)
 {
     using count_type = typename std::conditional<(sizeof(T) > sizeof(uint32_t)), uint64_t, uint32_t>::type;
-    return static_cast<unsigned int>(fmt::internal::count_digits(static_cast<count_type>(n)));
+    return static_cast<unsigned int>(fmt::
+// fmt 7.0.0 renamed the internal namespace to detail.
+// See: https://github.com/fmtlib/fmt/issues/1538
+#if FMT_VERSION < 70000
+            internal
+#else
+            detail
+#endif
+        ::count_digits(static_cast<count_type>(n)));
 }
 
 inline void pad2(int n, memory_buf_t &dest)

include/spdlog/details/tcp_client-windows.h

@@ -8,8 +8,8 @@
 #include <spdlog/common.h>
 #include <spdlog/details/os.h>
 
-#include <windows.h>
 #include <winsock2.h>
+#include <windows.h>
 #include <ws2tcpip.h>
 #include <stdlib.h>
 #include <stdio.h>

include/spdlog/details/tcp_client.h

@@ -75,7 +75,11 @@ public:
         int last_errno = 0;
         for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
         {
-            int const flags = SOCK_CLOEXEC;
+#if defined(SOCK_CLOEXEC)
+            const int flags = SOCK_CLOEXEC;
+#else
+            const int flags = 0;
+#endif
             socket_ = ::socket(rp->ai_family, rp->ai_socktype | flags, rp->ai_protocol);
             if (socket_ == -1)
             {
@@ -87,12 +91,9 @@ public:
             {
                 break;
             }
-            else
-            {
-                last_errno = errno;
-                ::close(socket_);
-                socket_ = -1;
-            }
+            last_errno = errno;
+            ::close(socket_);
+            socket_ = -1;
         }
         ::freeaddrinfo(addrinfo_result);
         if (socket_ == -1)

include/spdlog/fmt/bin_to_hex.h

@@ -92,7 +92,7 @@ struct formatter<spdlog::details::dump_info<T>>
     auto parse(ParseContext &ctx) -> decltype(ctx.begin())
     {
         auto it = ctx.begin();
-        while (*it && *it != '}')
+        while (it != ctx.end() && *it != '}')
         {
             switch (*it)
             {

include/spdlog/fmt/bundled/chrono.h

@@ -48,7 +48,7 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
     // From fits in To without any problem.
   } else {
     // From does not always fit in To, resort to a dynamic check.
-    if (from < T::min() || from > T::max()) {
+    if (from < (T::min)() || from > (T::max)()) {
       // outside range.
       ec = 1;
       return {};
@@ -74,7 +74,7 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
 
   if (F::is_signed && !T::is_signed) {
     // From may be negative, not allowed!
-    if (fmt::internal::is_negative(from)) {
+    if (fmt::detail::is_negative(from)) {
       ec = 1;
       return {};
     }
@@ -84,7 +84,7 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
       // yes, From always fits in To.
     } else {
       // from may not fit in To, we have to do a dynamic check
-      if (from > static_cast<From>(T::max())) {
+      if (from > static_cast<From>((T::max)())) {
         ec = 1;
         return {};
       }
@@ -97,7 +97,7 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
       // yes, From always fits in To.
     } else {
       // from may not fit in To, we have to do a dynamic check
-      if (from > static_cast<From>(T::max())) {
+      if (from > static_cast<From>((T::max)())) {
         // outside range.
         ec = 1;
         return {};
@@ -141,7 +141,7 @@ FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
 
   // catch the only happy case
   if (std::isfinite(from)) {
-    if (from >= T::lowest() && from <= T::max()) {
+    if (from >= T::lowest() && from <= (T::max)()) {
       return static_cast<To>(from);
     }
     // not within range.
@@ -195,12 +195,13 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
   }
   // multiply with Factor::num without overflow or underflow
   if (Factor::num != 1) {
-    const auto max1 = internal::max_value<IntermediateRep>() / Factor::num;
+    const auto max1 = detail::max_value<IntermediateRep>() / Factor::num;
     if (count > max1) {
       ec = 1;
       return {};
     }
-    const auto min1 = std::numeric_limits<IntermediateRep>::min() / Factor::num;
+    const auto min1 =
+        (std::numeric_limits<IntermediateRep>::min)() / Factor::num;
     if (count < min1) {
       ec = 1;
       return {};
@@ -269,7 +270,7 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
 
   // multiply with Factor::num without overflow or underflow
   if (Factor::num != 1) {
-    constexpr auto max1 = internal::max_value<IntermediateRep>() /
+    constexpr auto max1 = detail::max_value<IntermediateRep>() /
                           static_cast<IntermediateRep>(Factor::num);
     if (count > max1) {
       ec = 1;
@@ -306,12 +307,12 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
 // Usage: f FMT_NOMACRO()
 #define FMT_NOMACRO
 
-namespace internal {
+namespace detail {
 inline null<> localtime_r FMT_NOMACRO(...) { return null<>(); }
 inline null<> localtime_s(...) { return null<>(); }
 inline null<> gmtime_r(...) { return null<>(); }
 inline null<> gmtime_s(...) { return null<>(); }
-}  // namespace internal
+}  // namespace detail
 
 // Thread-safe replacement for std::localtime
 inline std::tm localtime(std::time_t time) {
@@ -322,22 +323,22 @@ inline std::tm localtime(std::time_t time) {
     dispatcher(std::time_t t) : time_(t) {}
 
     bool run() {
-      using namespace fmt::internal;
+      using namespace fmt::detail;
       return handle(localtime_r(&time_, &tm_));
     }
 
     bool handle(std::tm* tm) { return tm != nullptr; }
 
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
+    bool handle(detail::null<>) {
+      using namespace fmt::detail;
       return fallback(localtime_s(&tm_, &time_));
     }
 
     bool fallback(int res) { return res == 0; }
 
 #if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
-      using namespace fmt::internal;
+    bool fallback(detail::null<>) {
+      using namespace fmt::detail;
       std::tm* tm = std::localtime(&time_);
       if (tm) tm_ = *tm;
       return tm != nullptr;
@@ -359,21 +360,21 @@ inline std::tm gmtime(std::time_t time) {
     dispatcher(std::time_t t) : time_(t) {}
 
     bool run() {
-      using namespace fmt::internal;
+      using namespace fmt::detail;
       return handle(gmtime_r(&time_, &tm_));
     }
 
     bool handle(std::tm* tm) { return tm != nullptr; }
 
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
+    bool handle(detail::null<>) {
+      using namespace fmt::detail;
       return fallback(gmtime_s(&tm_, &time_));
     }
 
     bool fallback(int res) { return res == 0; }
 
 #if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
+    bool fallback(detail::null<>) {
       std::tm* tm = std::gmtime(&time_);
       if (tm) tm_ = *tm;
       return tm != nullptr;
@@ -386,17 +387,17 @@ inline std::tm gmtime(std::time_t time) {
   return gt.tm_;
 }
 
-namespace internal {
-inline std::size_t strftime(char* str, std::size_t count, const char* format,
-                            const std::tm* time) {
+namespace detail {
+inline size_t strftime(char* str, size_t count, const char* format,
+                       const std::tm* time) {
   return std::strftime(str, count, format, time);
 }
 
-inline std::size_t strftime(wchar_t* str, std::size_t count,
-                            const wchar_t* format, const std::tm* time) {
+inline size_t strftime(wchar_t* str, size_t count, const wchar_t* format,
+                       const std::tm* time) {
   return std::wcsftime(str, count, format, time);
 }
-}  // namespace internal
+}  // namespace detail
 
 template <typename Char> struct formatter<std::tm, Char> {
   template <typename ParseContext>
@@ -405,7 +406,7 @@ template <typename Char> struct formatter<std::tm, Char> {
     if (it != ctx.end() && *it == ':') ++it;
     auto end = it;
     while (end != ctx.end() && *end != '}') ++end;
-    tm_format.reserve(internal::to_unsigned(end - it + 1));
+    tm_format.reserve(detail::to_unsigned(end - it + 1));
     tm_format.append(it, end);
     tm_format.push_back('\0');
     return end;
@@ -414,11 +415,10 @@ template <typename Char> struct formatter<std::tm, Char> {
   template <typename FormatContext>
   auto format(const std::tm& tm, FormatContext& ctx) -> decltype(ctx.out()) {
     basic_memory_buffer<Char> buf;
-    std::size_t start = buf.size();
+    size_t start = buf.size();
     for (;;) {
-      std::size_t size = buf.capacity() - start;
-      std::size_t count =
-          internal::strftime(&buf[start], size, &tm_format[0], &tm);
+      size_t size = buf.capacity() - start;
+      size_t count = detail::strftime(&buf[start], size, &tm_format[0], &tm);
       if (count != 0) {
         buf.resize(start + count);
         break;
@@ -430,7 +430,7 @@ template <typename Char> struct formatter<std::tm, Char> {
         // https://github.com/fmtlib/fmt/issues/367
         break;
       }
-      const std::size_t MIN_GROWTH = 10;
+      const size_t MIN_GROWTH = 10;
       buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
     }
     return std::copy(buf.begin(), buf.end(), ctx.out());
@@ -439,7 +439,7 @@ template <typename Char> struct formatter<std::tm, Char> {
   basic_memory_buffer<Char> tm_format;
 };
 
-namespace internal {
+namespace detail {
 template <typename Period> FMT_CONSTEXPR const char* get_units() {
   return nullptr;
 }
@@ -768,19 +768,25 @@ OutputIt format_duration_value(OutputIt out, Rep val, int precision) {
   return format_to(out, std::is_floating_point<Rep>::value ? fp_f : format,
                    val);
 }
+template <typename Char, typename OutputIt>
+OutputIt copy_unit(string_view unit, OutputIt out, Char) {
+  return std::copy(unit.begin(), unit.end(), out);
+}
+
+template <typename OutputIt>
+OutputIt copy_unit(string_view unit, OutputIt out, wchar_t) {
+  // This works when wchar_t is UTF-32 because units only contain characters
+  // that have the same representation in UTF-16 and UTF-32.
+  utf8_to_utf16 u(unit);
+  return std::copy(u.c_str(), u.c_str() + u.size(), out);
+}
 
 template <typename Char, typename Period, typename OutputIt>
 OutputIt format_duration_unit(OutputIt out) {
-  if (const char* unit = get_units<Period>()) {
-    string_view s(unit);
-    if (const_check(std::is_same<Char, wchar_t>())) {
-      utf8_to_utf16 u(s);
-      return std::copy(u.c_str(), u.c_str() + u.size(), out);
-    }
-    return std::copy(s.begin(), s.end(), out);
-  }
+  if (const char* unit = get_units<Period>())
+    return copy_unit(string_view(unit), out, Char());
   const Char num_f[] = {'[', '{', '}', ']', 's', 0};
-  if (Period::den == 1) return format_to(out, num_f, Period::num);
+  if (const_check(Period::den == 1)) return format_to(out, num_f, Period::num);
   const Char num_def_f[] = {'[', '{', '}', '/', '{', '}', ']', 's', 0};
   return format_to(out, num_def_f, Period::num, Period::den);
 }
@@ -874,9 +880,9 @@ struct chrono_formatter {
     if (isnan(value)) return write_nan();
     uint32_or_64_or_128_t<int> n =
         to_unsigned(to_nonnegative_int(value, max_value<int>()));
-    int num_digits = internal::count_digits(n);
+    int num_digits = detail::count_digits(n);
     if (width > num_digits) out = std::fill_n(out, width - num_digits, '0');
-    out = format_decimal<char_type>(out, n, num_digits);
+    out = format_decimal<char_type>(out, n, num_digits).end;
   }
 
   void write_nan() { std::copy_n("nan", 3, out); }
@@ -1004,14 +1010,14 @@ struct chrono_formatter {
     out = format_duration_unit<char_type, Period>(out);
   }
 };
-}  // namespace internal
+}  // namespace detail
 
 template <typename Rep, typename Period, typename Char>
 struct formatter<std::chrono::duration<Rep, Period>, Char> {
  private:
   basic_format_specs<Char> specs;
   int precision;
-  using arg_ref_type = internal::arg_ref<Char>;
+  using arg_ref_type = detail::arg_ref<Char>;
   arg_ref_type width_ref;
   arg_ref_type precision_ref;
   mutable basic_string_view<Char> format_str;
@@ -1032,7 +1038,7 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
       return arg_ref_type(arg_id);
     }
 
-    FMT_CONSTEXPR arg_ref_type make_arg_ref(internal::auto_id) {
+    FMT_CONSTEXPR arg_ref_type make_arg_ref(detail::auto_id) {
       return arg_ref_type(context.next_arg_id());
     }
 
@@ -1062,17 +1068,17 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
     auto begin = ctx.begin(), end = ctx.end();
     if (begin == end || *begin == '}') return {begin, begin};
     spec_handler handler{*this, ctx, format_str};
-    begin = internal::parse_align(begin, end, handler);
+    begin = detail::parse_align(begin, end, handler);
     if (begin == end) return {begin, begin};
-    begin = internal::parse_width(begin, end, handler);
+    begin = detail::parse_width(begin, end, handler);
     if (begin == end) return {begin, begin};
     if (*begin == '.') {
       if (std::is_floating_point<Rep>::value)
-        begin = internal::parse_precision(begin, end, handler);
+        begin = detail::parse_precision(begin, end, handler);
       else
         handler.on_error("precision not allowed for this argument type");
     }
-    end = parse_chrono_format(begin, end, internal::chrono_format_checker());
+    end = parse_chrono_format(begin, end, detail::chrono_format_checker());
     return {begin, end};
   }
 
@@ -1083,7 +1089,7 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
       -> decltype(ctx.begin()) {
     auto range = do_parse(ctx);
     format_str = basic_string_view<Char>(
-        &*range.begin, internal::to_unsigned(range.end - range.begin));
+        &*range.begin, detail::to_unsigned(range.end - range.begin));
     return range.end;
   }
 
@@ -1094,23 +1100,21 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
     // is not specified.
     basic_memory_buffer<Char> buf;
     auto out = std::back_inserter(buf);
-    using range = internal::output_range<decltype(ctx.out()), Char>;
-    internal::basic_writer<range> w(range(ctx.out()));
-    internal::handle_dynamic_spec<internal::width_checker>(specs.width,
-                                                           width_ref, ctx);
-    internal::handle_dynamic_spec<internal::precision_checker>(
-        precision, precision_ref, ctx);
+    detail::handle_dynamic_spec<detail::width_checker>(specs.width, width_ref,
+                                                       ctx);
+    detail::handle_dynamic_spec<detail::precision_checker>(precision,
+                                                           precision_ref, ctx);
     if (begin == end || *begin == '}') {
-      out = internal::format_duration_value<Char>(out, d.count(), precision);
-      internal::format_duration_unit<Char, Period>(out);
+      out = detail::format_duration_value<Char>(out, d.count(), precision);
+      detail::format_duration_unit<Char, Period>(out);
     } else {
-      internal::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
+      detail::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
           ctx, out, d);
       f.precision = precision;
       parse_chrono_format(begin, end, f);
     }
-    w.write(buf.data(), buf.size(), specs);
-    return w.out();
+    return detail::write(
+        ctx.out(), basic_string_view<Char>(buf.data(), buf.size()), specs);
   }
 };
 

include/spdlog/fmt/bundled/color.h

@@ -198,7 +198,7 @@ struct rgb {
   uint8_t b;
 };
 
-namespace internal {
+namespace detail {
 
 // color is a struct of either a rgb color or a terminal color.
 struct color_type {
@@ -221,7 +221,7 @@ struct color_type {
     uint32_t rgb_color;
   } value;
 };
-}  // namespace internal
+}  // namespace detail
 
 // Experimental text formatting support.
 class text_style {
@@ -298,11 +298,11 @@ class text_style {
   FMT_CONSTEXPR bool has_emphasis() const FMT_NOEXCEPT {
     return static_cast<uint8_t>(ems) != 0;
   }
-  FMT_CONSTEXPR internal::color_type get_foreground() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR detail::color_type get_foreground() const FMT_NOEXCEPT {
     FMT_ASSERT(has_foreground(), "no foreground specified for this style");
     return foreground_color;
   }
-  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR detail::color_type get_background() const FMT_NOEXCEPT {
     FMT_ASSERT(has_background(), "no background specified for this style");
     return background_color;
   }
@@ -313,7 +313,7 @@ class text_style {
 
  private:
   FMT_CONSTEXPR text_style(bool is_foreground,
-                           internal::color_type text_color) FMT_NOEXCEPT
+                           detail::color_type text_color) FMT_NOEXCEPT
       : set_foreground_color(),
         set_background_color(),
         ems() {
@@ -326,23 +326,23 @@ class text_style {
     }
   }
 
-  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
+  friend FMT_CONSTEXPR_DECL text_style fg(detail::color_type foreground)
       FMT_NOEXCEPT;
-  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
+  friend FMT_CONSTEXPR_DECL text_style bg(detail::color_type background)
       FMT_NOEXCEPT;
 
-  internal::color_type foreground_color;
-  internal::color_type background_color;
+  detail::color_type foreground_color;
+  detail::color_type background_color;
   bool set_foreground_color;
   bool set_background_color;
   emphasis ems;
 };
 
-FMT_CONSTEXPR text_style fg(internal::color_type foreground) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style fg(detail::color_type foreground) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/true, foreground);
 }
 
-FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style bg(detail::color_type background) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/false, background);
 }
 
@@ -350,21 +350,21 @@ FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
   return text_style(lhs) | rhs;
 }
 
-namespace internal {
+namespace detail {
 
 template <typename Char> struct ansi_color_escape {
-  FMT_CONSTEXPR ansi_color_escape(internal::color_type text_color,
+  FMT_CONSTEXPR ansi_color_escape(detail::color_type text_color,
                                   const char* esc) FMT_NOEXCEPT {
     // If we have a terminal color, we need to output another escape code
     // sequence.
     if (!text_color.is_rgb) {
-      bool is_background = esc == internal::data::background_color;
+      bool is_background = esc == detail::data::background_color;
       uint32_t value = text_color.value.term_color;
       // Background ASCII codes are the same as the foreground ones but with
       // 10 more.
       if (is_background) value += 10u;
 
-      std::size_t index = 0;
+      size_t index = 0;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
 
@@ -398,7 +398,7 @@ template <typename Char> struct ansi_color_escape {
     if (em_bits & static_cast<uint8_t>(emphasis::strikethrough))
       em_codes[3] = 9;
 
-    std::size_t index = 0;
+    size_t index = 0;
     for (int i = 0; i < 4; ++i) {
       if (!em_codes[i]) continue;
       buffer[index++] = static_cast<Char>('\x1b');
@@ -429,14 +429,14 @@ template <typename Char> struct ansi_color_escape {
 
 template <typename Char>
 FMT_CONSTEXPR ansi_color_escape<Char> make_foreground_color(
-    internal::color_type foreground) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(foreground, internal::data::foreground_color);
+    detail::color_type foreground) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(foreground, detail::data::foreground_color);
 }
 
 template <typename Char>
 FMT_CONSTEXPR ansi_color_escape<Char> make_background_color(
-    internal::color_type background) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(background, internal::data::background_color);
+    detail::color_type background) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(background, detail::data::background_color);
 }
 
 template <typename Char>
@@ -455,11 +455,11 @@ inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
 }
 
 template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::reset_color, stream);
+  fputs(detail::data::reset_color, stream);
 }
 
 template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::wreset_color, stream);
+  fputs(detail::data::wreset_color, stream);
 }
 
 template <typename Char>
@@ -476,33 +476,31 @@ void vformat_to(basic_memory_buffer<Char>& buf, const text_style& ts,
   bool has_style = false;
   if (ts.has_emphasis()) {
     has_style = true;
-    auto emphasis = internal::make_emphasis<Char>(ts.get_emphasis());
+    auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
     buf.append(emphasis.begin(), emphasis.end());
   }
   if (ts.has_foreground()) {
     has_style = true;
-    auto foreground =
-        internal::make_foreground_color<Char>(ts.get_foreground());
+    auto foreground = detail::make_foreground_color<Char>(ts.get_foreground());
     buf.append(foreground.begin(), foreground.end());
   }
   if (ts.has_background()) {
     has_style = true;
-    auto background =
-        internal::make_background_color<Char>(ts.get_background());
+    auto background = detail::make_background_color<Char>(ts.get_background());
     buf.append(background.begin(), background.end());
   }
-  internal::vformat_to(buf, format_str, args);
-  if (has_style) internal::reset_color<Char>(buf);
+  detail::vformat_to(buf, format_str, args);
+  if (has_style) detail::reset_color<Char>(buf);
 }
-}  // namespace internal
+}  // namespace detail
 
 template <typename S, typename Char = char_t<S>>
 void vprint(std::FILE* f, const text_style& ts, const S& format,
             basic_format_args<buffer_context<Char>> args) {
   basic_memory_buffer<Char> buf;
-  internal::vformat_to(buf, ts, to_string_view(format), args);
+  detail::vformat_to(buf, ts, to_string_view(format), args);
   buf.push_back(Char(0));
-  internal::fputs(buf.data(), f);
+  detail::fputs(buf.data(), f);
 }
 
 /**
@@ -513,10 +511,10 @@ void vprint(std::FILE* f, const text_style& ts, const S& format,
                "Elapsed time: {0:.2f} seconds", 1.23);
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
 void print(std::FILE* f, const text_style& ts, const S& format_str,
            const Args&... args) {
-  internal::check_format_string<Args...>(format_str);
+  detail::check_format_string<Args...>(format_str);
   using context = buffer_context<char_t<S>>;
   format_arg_store<context, Args...> as{args...};
   vprint(f, ts, format_str, basic_format_args<context>(as));
@@ -530,7 +528,7 @@ void print(std::FILE* f, const text_style& ts, const S& format_str,
                "Elapsed time: {0:.2f} seconds", 1.23);
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
 void print(const text_style& ts, const S& format_str, const Args&... args) {
   return print(stdout, ts, format_str, args...);
 }
@@ -540,7 +538,7 @@ inline std::basic_string<Char> vformat(
     const text_style& ts, const S& format_str,
     basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buf;
-  internal::vformat_to(buf, ts, to_string_view(format_str), args);
+  detail::vformat_to(buf, ts, to_string_view(format_str), args);
   return fmt::to_string(buf);
 }
 
@@ -560,7 +558,7 @@ template <typename S, typename... Args, typename Char = char_t<S>>
 inline std::basic_string<Char> format(const text_style& ts, const S& format_str,
                                       const Args&... args) {
   return vformat(ts, to_string_view(format_str),
-                 internal::make_args_checked<Args...>(format_str, args...));
+                 detail::make_args_checked<Args...>(format_str, args...));
 }
 
 FMT_END_NAMESPACE

include/spdlog/fmt/bundled/compile.h

@@ -13,7 +13,33 @@
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
+
+// A compile-time string which is compiled into fast formatting code.
+class compiled_string {};
+
+template <typename S>
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
+
+/**
+  \rst
+  Converts a string literal *s* into a format string that will be parsed at
+  compile time and converted into efficient formatting code. Requires C++17
+  ``constexpr if`` compiler support.
+
+  **Example**::
+
+    // Converts 42 into std::string using the most efficient method and no
+    // runtime format string processing.
+    std::string s = fmt::format(FMT_COMPILE("{}"), 42);
+  \endrst
+ */
+#define FMT_COMPILE(s) FMT_STRING_IMPL(s, fmt::detail::compiled_string)
+
+template <typename T, typename... Tail>
+const T& first(const T& value, const Tail&...) {
+  return value;
+}
 
 // Part of a compiled format string. It can be either literal text or a
 // replacement field.
@@ -62,13 +88,15 @@ template <typename Char> struct part_counter {
     if (begin != end) ++num_parts;
   }
 
-  FMT_CONSTEXPR void on_arg_id() { ++num_parts; }
-  FMT_CONSTEXPR void on_arg_id(int) { ++num_parts; }
-  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char>) { ++num_parts; }
+  FMT_CONSTEXPR int on_arg_id() { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(int) { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char>) {
+    return ++num_parts, 0;
+  }
 
-  FMT_CONSTEXPR void on_replacement_field(const Char*) {}
+  FMT_CONSTEXPR void on_replacement_field(int, const Char*) {}
 
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
                                             const Char* end) {
     // Find the matching brace.
     unsigned brace_counter = 0;
@@ -116,25 +144,28 @@ class format_string_compiler : public error_handler {
       handler_(part::make_text({begin, to_unsigned(end - begin)}));
   }
 
-  FMT_CONSTEXPR void on_arg_id() {
+  FMT_CONSTEXPR int on_arg_id() {
     part_ = part::make_arg_index(parse_context_.next_arg_id());
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_arg_id(int id) {
+  FMT_CONSTEXPR int on_arg_id(int id) {
     parse_context_.check_arg_id(id);
     part_ = part::make_arg_index(id);
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char> id) {
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char> id) {
     part_ = part::make_arg_name(id);
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_replacement_field(const Char* ptr) {
+  FMT_CONSTEXPR void on_replacement_field(int, const Char* ptr) {
     part_.arg_id_end = ptr;
     handler_(part_);
   }
 
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
                                             const Char* end) {
     auto repl = typename part::replacement();
     dynamic_specs_handler<basic_format_parse_context<Char>> handler(
@@ -160,23 +191,24 @@ FMT_CONSTEXPR void compile_format_string(basic_string_view<Char> format_str,
       format_string_compiler<Char, PartHandler>(format_str, handler));
 }
 
-template <typename Range, typename Context, typename Id>
+template <typename OutputIt, typename Context, typename Id>
 void format_arg(
-    basic_format_parse_context<typename Range::value_type>& parse_ctx,
+    basic_format_parse_context<typename Context::char_type>& parse_ctx,
     Context& ctx, Id arg_id) {
-  ctx.advance_to(
-      visit_format_arg(arg_formatter<Range>(ctx, &parse_ctx), ctx.arg(arg_id)));
+  ctx.advance_to(visit_format_arg(
+      arg_formatter<OutputIt, typename Context::char_type>(ctx, &parse_ctx),
+      ctx.arg(arg_id)));
 }
 
 // vformat_to is defined in a subnamespace to prevent ADL.
 namespace cf {
-template <typename Context, typename Range, typename CompiledFormat>
-auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
-    -> typename Context::iterator {
+template <typename Context, typename OutputIt, typename CompiledFormat>
+auto vformat_to(OutputIt out, CompiledFormat& cf,
+                basic_format_args<Context> args) -> typename Context::iterator {
   using char_type = typename Context::char_type;
   basic_format_parse_context<char_type> parse_ctx(
       to_string_view(cf.format_str_));
-  Context ctx(out.begin(), args);
+  Context ctx(out, args);
 
   const auto& parts = cf.parts();
   for (auto part_it = std::begin(parts); part_it != std::end(parts);
@@ -197,12 +229,12 @@ auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
 
     case format_part_t::kind::arg_index:
       advance_to(parse_ctx, part.arg_id_end);
-      internal::format_arg<Range>(parse_ctx, ctx, value.arg_index);
+      detail::format_arg<OutputIt>(parse_ctx, ctx, value.arg_index);
       break;
 
     case format_part_t::kind::arg_name:
       advance_to(parse_ctx, part.arg_id_end);
-      internal::format_arg<Range>(parse_ctx, ctx, value.str);
+      detail::format_arg<OutputIt>(parse_ctx, ctx, value.str);
       break;
 
     case format_part_t::kind::replacement: {
@@ -226,7 +258,9 @@ auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
 
       advance_to(parse_ctx, part.arg_id_end);
       ctx.advance_to(
-          visit_format_arg(arg_formatter<Range>(ctx, nullptr, &specs), arg));
+          visit_format_arg(arg_formatter<OutputIt, typename Context::char_type>(
+                               ctx, nullptr, &specs),
+                           arg));
       break;
     }
     }
@@ -240,7 +274,7 @@ struct basic_compiled_format {};
 template <typename S, typename = void>
 struct compiled_format_base : basic_compiled_format {
   using char_type = char_t<S>;
-  using parts_container = std::vector<internal::format_part<char_type>>;
+  using parts_container = std::vector<detail::format_part<char_type>>;
 
   parts_container compiled_parts;
 
@@ -305,7 +339,7 @@ struct compiled_format_base<S, enable_if_t<is_compile_string<S>::value>>
   const parts_container& parts() const {
     static FMT_CONSTEXPR_DECL const auto compiled_parts =
         compile_to_parts<char_type, num_format_parts>(
-            internal::to_string_view(S()));
+            detail::to_string_view(S()));
     return compiled_parts.data;
   }
 };
@@ -318,8 +352,8 @@ class compiled_format : private compiled_format_base<S> {
  private:
   basic_string_view<char_type> format_str_;
 
-  template <typename Context, typename Range, typename CompiledFormat>
-  friend auto cf::vformat_to(Range out, CompiledFormat& cf,
+  template <typename Context, typename OutputIt, typename CompiledFormat>
+  friend auto cf::vformat_to(OutputIt out, CompiledFormat& cf,
                              basic_format_args<Context> args) ->
       typename Context::iterator;
 
@@ -359,8 +393,7 @@ template <typename Char> struct text {
 
   template <typename OutputIt, typename... Args>
   OutputIt format(OutputIt out, const Args&...) const {
-    // TODO: reserve
-    return copy_str<Char>(data.begin(), data.end(), out);
+    return write<Char>(out, data);
   }
 };
 
@@ -373,33 +406,6 @@ constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
   return {{&s[pos], size}};
 }
 
-template <typename Char, typename OutputIt, typename T,
-          std::enable_if_t<std::is_integral_v<T>, int> = 0>
-OutputIt format_default(OutputIt out, T value) {
-  // TODO: reserve
-  format_int fi(value);
-  return std::copy(fi.data(), fi.data() + fi.size(), out);
-}
-
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, double value) {
-  writer w(out);
-  w.write(value);
-  return w.out();
-}
-
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, Char value) {
-  *out++ = value;
-  return out;
-}
-
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, const Char* value) {
-  auto length = std::char_traits<Char>::length(value);
-  return copy_str<Char>(value, value + length, out);
-}
-
 // A replacement field that refers to argument N.
 template <typename Char, typename T, int N> struct field {
   using char_type = Char;
@@ -408,13 +414,30 @@ template <typename Char, typename T, int N> struct field {
   OutputIt format(OutputIt out, const Args&... args) const {
     // This ensures that the argument type is convertile to `const T&`.
     const T& arg = get<N>(args...);
-    return format_default<Char>(out, arg);
+    return write<Char>(out, arg);
   }
 };
 
 template <typename Char, typename T, int N>
 struct is_compiled_format<field<Char, T, N>> : std::true_type {};
 
+// A replacement field that refers to argument N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  mutable formatter<T, Char> fmt;
+
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&... args) const {
+    // This ensures that the argument type is convertile to `const T&`.
+    const T& arg = get<N>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, {});
+    return fmt.format(arg, ctx);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<spec_field<Char, T, N>> : std::true_type {};
+
 template <typename L, typename R> struct concat {
   L lhs;
   R rhs;
@@ -450,7 +473,8 @@ constexpr auto compile_format_string(S format_str);
 
 template <typename Args, size_t POS, int ID, typename T, typename S>
 constexpr auto parse_tail(T head, S format_str) {
-  if constexpr (POS != to_string_view(format_str).size()) {
+  if constexpr (POS !=
+                basic_string_view<typename S::char_type>(format_str).size()) {
     constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
     if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
                                unknown_format>())
@@ -462,6 +486,21 @@ constexpr auto parse_tail(T head, S format_str) {
   }
 }
 
+template <typename T, typename Char> struct parse_specs_result {
+  formatter<T, Char> fmt;
+  size_t end;
+};
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos) {
+  str.remove_prefix(pos);
+  auto ctx = basic_format_parse_context<Char>(str);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + (end - str.data()) + 1};
+}
+
 // Compiles a non-empty format string and returns the compiled representation
 // or unknown_format() on unrecognized input.
 template <typename Args, size_t POS, int ID, typename S>
@@ -475,12 +514,13 @@ constexpr auto compile_format_string(S format_str) {
       return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
     } else if constexpr (str[POS + 1] == '}') {
       using type = get_type<ID, Args>;
-      if constexpr (std::is_same<type, int>::value) {
-        return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
-                                                 format_str);
-      } else {
-        return unknown_format();
-      }
+      return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
+                                               format_str);
+    } else if constexpr (str[POS + 1] == ':') {
+      using type = get_type<ID, Args>;
+      constexpr auto result = parse_specs<type>(str, POS + 2);
+      return parse_tail<Args, result.end, ID + 1>(
+          spec_field<char_type, type, ID>{result.fmt}, format_str);
     } else {
       return unknown_format();
     }
@@ -494,100 +534,130 @@ constexpr auto compile_format_string(S format_str) {
                                      format_str);
   }
 }
-#endif  // __cpp_if_constexpr
-}  // namespace internal
 
-#if FMT_USE_CONSTEXPR
-#  ifdef __cpp_if_constexpr
 template <typename... Args, typename S,
-          FMT_ENABLE_IF(is_compile_string<S>::value)>
+          FMT_ENABLE_IF(is_compile_string<S>::value ||
+                        detail::is_compiled_string<S>::value)>
 constexpr auto compile(S format_str) {
   constexpr basic_string_view<typename S::char_type> str = format_str;
   if constexpr (str.size() == 0) {
-    return internal::make_text(str, 0, 0);
+    return detail::make_text(str, 0, 0);
   } else {
     constexpr auto result =
-        internal::compile_format_string<internal::type_list<Args...>, 0, 0>(
+        detail::compile_format_string<detail::type_list<Args...>, 0, 0>(
             format_str);
     if constexpr (std::is_same<remove_cvref_t<decltype(result)>,
-                               internal::unknown_format>()) {
-      return internal::compiled_format<S, Args...>(to_string_view(format_str));
+                               detail::unknown_format>()) {
+      return detail::compiled_format<S, Args...>(to_string_view(format_str));
     } else {
       return result;
     }
   }
 }
-
-template <typename CompiledFormat, typename... Args,
-          typename Char = typename CompiledFormat::char_type,
-          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
-std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
-  basic_memory_buffer<Char> buffer;
-  cf.format(std::back_inserter(buffer), args...);
-  return to_string(buffer);
-}
-
-template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
-OutputIt format_to(OutputIt out, const CompiledFormat& cf,
-                   const Args&... args) {
-  return cf.format(out, args...);
-}
-#  else
+#else
 template <typename... Args, typename S,
           FMT_ENABLE_IF(is_compile_string<S>::value)>
-constexpr auto compile(S format_str) -> internal::compiled_format<S, Args...> {
-  return internal::compiled_format<S, Args...>(to_string_view(format_str));
+constexpr auto compile(S format_str) -> detail::compiled_format<S, Args...> {
+  return detail::compiled_format<S, Args...>(to_string_view(format_str));
 }
-#  endif  // __cpp_if_constexpr
-#endif    // FMT_USE_CONSTEXPR
+#endif  // __cpp_if_constexpr
 
 // Compiles the format string which must be a string literal.
 template <typename... Args, typename Char, size_t N>
 auto compile(const Char (&format_str)[N])
-    -> internal::compiled_format<const Char*, Args...> {
-  return internal::compiled_format<const Char*, Args...>(
+    -> detail::compiled_format<const Char*, Args...> {
+  return detail::compiled_format<const Char*, Args...>(
       basic_string_view<Char>(format_str, N - 1));
 }
+}  // namespace detail
+
+// DEPRECATED! use FMT_COMPILE instead.
+template <typename... Args>
+FMT_DEPRECATED auto compile(const Args&... args)
+    -> decltype(detail::compile(args...)) {
+  return detail::compile(args...);
+}
+
+#if FMT_USE_CONSTEXPR
+#  ifdef __cpp_if_constexpr
 
 template <typename CompiledFormat, typename... Args,
           typename Char = typename CompiledFormat::char_type,
-          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
-                                        CompiledFormat>::value)>
-std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE std::basic_string<Char> format(const CompiledFormat& cf,
+                                          const Args&... args) {
   basic_memory_buffer<Char> buffer;
-  using range = buffer_range<Char>;
-  using context = buffer_context<Char>;
-  internal::cf::vformat_to<context>(range(buffer), cf,
-                                    make_format_args<context>(args...));
+  detail::buffer<Char>& base = buffer;
+  cf.format(std::back_inserter(base), args...);
   return to_string(buffer);
 }
 
 template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  return cf.format(out, args...);
+}
+#  endif  // __cpp_if_constexpr
+#endif    // FMT_USE_CONSTEXPR
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(std::is_base_of<detail::basic_compiled_format,
+                                        CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using context = buffer_context<Char>;
+  detail::buffer<Char>& base = buffer;
+  detail::cf::vformat_to<context>(std::back_inserter(base), cf,
+                                  make_format_args<context>(args...));
+  return to_string(buffer);
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+  constexpr basic_string_view<typename S::char_type> str = S();
+  if (str.size() == 2 && str[0] == '{' && str[1] == '}')
+    return fmt::to_string(detail::first(args...));
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format(compiled, std::forward<Args>(args)...);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(std::is_base_of<detail::basic_compiled_format,
                                         CompiledFormat>::value)>
 OutputIt format_to(OutputIt out, const CompiledFormat& cf,
                    const Args&... args) {
   using char_type = typename CompiledFormat::char_type;
-  using range = internal::output_range<OutputIt, char_type>;
   using context = format_context_t<OutputIt, char_type>;
-  return internal::cf::vformat_to<context>(range(out), cf,
-                                           make_format_args<context>(args...));
+  return detail::cf::vformat_to<context>(out, cf,
+                                         make_format_args<context>(args...));
 }
 
-template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value)>
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+OutputIt format_to(OutputIt out, const S&, const Args&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format_to(out, compiled, args...);
+}
+
+template <
+    typename OutputIt, typename CompiledFormat, typename... Args,
+    FMT_ENABLE_IF(detail::is_output_iterator<OutputIt>::value&& std::is_base_of<
+                  detail::basic_compiled_format, CompiledFormat>::value)>
 format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n,
                                          const CompiledFormat& cf,
                                          const Args&... args) {
   auto it =
-      format_to(internal::truncating_iterator<OutputIt>(out, n), cf, args...);
+      format_to(detail::truncating_iterator<OutputIt>(out, n), cf, args...);
   return {it.base(), it.count()};
 }
 
 template <typename CompiledFormat, typename... Args>
-std::size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
-  return format_to(internal::counting_iterator(), cf, args...).count();
+size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
+  return format_to(detail::counting_iterator(), cf, args...).count();
 }
 
 FMT_END_NAMESPACE

include/spdlog/fmt/bundled/format-inl.h

@@ -15,6 +15,7 @@
 #include <cstdarg>
 #include <cstring>  // for std::memmove
 #include <cwchar>
+#include <exception>
 
 #include "format.h"
 #if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
@@ -22,8 +23,16 @@
 #endif
 
 #ifdef _WIN32
+#  if !defined(NOMINMAX) && !defined(WIN32_LEAN_AND_MEAN)
+#    define NOMINMAX
+#    define WIN32_LEAN_AND_MEAN
+#    include <windows.h>
+#    undef WIN32_LEAN_AND_MEAN
+#    undef NOMINMAX
+#  else
+#    include <windows.h>
+#  endif
 #  include <io.h>
-#  include <windows.h>
 #endif
 
 #ifdef _MSC_VER
@@ -33,15 +42,19 @@
 
 // Dummy implementations of strerror_r and strerror_s called if corresponding
 // system functions are not available.
-inline fmt::internal::null<> strerror_r(int, char*, ...) { return {}; }
-inline fmt::internal::null<> strerror_s(char*, std::size_t, ...) { return {}; }
+inline fmt::detail::null<> strerror_r(int, char*, ...) { return {}; }
+inline fmt::detail::null<> strerror_s(char*, size_t, ...) { return {}; }
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
 FMT_FUNC void assert_fail(const char* file, int line, const char* message) {
-  print(stderr, "{}:{}: assertion failed: {}", file, line, message);
-  std::abort();
+  // Use unchecked std::fprintf to avoid triggering another assertion when
+  // writing to stderr fails
+  std::fprintf(stderr, "%s:%d: assertion failed: %s", file, line, message);
+  // Chosen instead of std::abort to satisfy Clang in CUDA mode during device
+  // code pass.
+  std::terminate();
 }
 
 #ifndef _MSC_VER
@@ -67,14 +80,14 @@ inline int fmt_snprintf(char* buffer, size_t size, const char* format, ...) {
 //   other  - failure
 // Buffer should be at least of size 1.
 FMT_FUNC int safe_strerror(int error_code, char*& buffer,
-                           std::size_t buffer_size) FMT_NOEXCEPT {
+                           size_t buffer_size) FMT_NOEXCEPT {
   FMT_ASSERT(buffer != nullptr && buffer_size != 0, "invalid buffer");
 
   class dispatcher {
    private:
     int error_code_;
     char*& buffer_;
-    std::size_t buffer_size_;
+    size_t buffer_size_;
 
     // A noop assignment operator to avoid bogus warnings.
     void operator=(const dispatcher&) {}
@@ -97,7 +110,7 @@ FMT_FUNC int safe_strerror(int error_code, char*& buffer,
 
     // Handle the case when strerror_r is not available.
     FMT_MAYBE_UNUSED
-    int handle(internal::null<>) {
+    int handle(detail::null<>) {
       return fallback(strerror_s(buffer_, buffer_size_, error_code_));
     }
 
@@ -111,7 +124,7 @@ FMT_FUNC int safe_strerror(int error_code, char*& buffer,
 
 #if !FMT_MSC_VER
     // Fallback to strerror if strerror_r and strerror_s are not available.
-    int fallback(internal::null<>) {
+    int fallback(detail::null<>) {
       errno = 0;
       buffer_ = strerror(error_code_);
       return errno;
@@ -119,7 +132,7 @@ FMT_FUNC int safe_strerror(int error_code, char*& buffer,
 #endif
 
    public:
-    dispatcher(int err_code, char*& buf, std::size_t buf_size)
+    dispatcher(int err_code, char*& buf, size_t buf_size)
         : error_code_(err_code), buffer_(buf), buffer_size_(buf_size) {}
 
     int run() { return handle(strerror_r(error_code_, buffer_, buffer_size_)); }
@@ -127,7 +140,7 @@ FMT_FUNC int safe_strerror(int error_code, char*& buffer,
   return dispatcher(error_code, buffer, buffer_size).run();
 }
 
-FMT_FUNC void format_error_code(internal::buffer<char>& out, int error_code,
+FMT_FUNC void format_error_code(detail::buffer<char>& out, int error_code,
                                 string_view message) FMT_NOEXCEPT {
   // Report error code making sure that the output fits into
   // inline_buffer_size to avoid dynamic memory allocation and potential
@@ -136,20 +149,17 @@ FMT_FUNC void format_error_code(internal::buffer<char>& out, int error_code,
   static const char SEP[] = ": ";
   static const char ERROR_STR[] = "error ";
   // Subtract 2 to account for terminating null characters in SEP and ERROR_STR.
-  std::size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
+  size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
   auto abs_value = static_cast<uint32_or_64_or_128_t<int>>(error_code);
-  if (internal::is_negative(error_code)) {
+  if (detail::is_negative(error_code)) {
     abs_value = 0 - abs_value;
     ++error_code_size;
   }
-  error_code_size += internal::to_unsigned(internal::count_digits(abs_value));
-  internal::writer w(out);
-  if (message.size() <= inline_buffer_size - error_code_size) {
-    w.write(message);
-    w.write(SEP);
-  }
-  w.write(ERROR_STR);
-  w.write(error_code);
+  error_code_size += detail::to_unsigned(detail::count_digits(abs_value));
+  auto it = std::back_inserter(out);
+  if (message.size() <= inline_buffer_size - error_code_size)
+    format_to(it, "{}{}", message, SEP);
+  format_to(it, "{}{}", ERROR_STR, error_code);
   assert(out.size() <= inline_buffer_size);
 }
 
@@ -168,10 +178,10 @@ FMT_FUNC void fwrite_fully(const void* ptr, size_t size, size_t count,
   size_t written = std::fwrite(ptr, size, count, stream);
   if (written < count) FMT_THROW(system_error(errno, "cannot write to file"));
 }
-}  // namespace internal
+}  // namespace detail
 
 #if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
-namespace internal {
+namespace detail {
 
 template <typename Locale>
 locale_ref::locale_ref(const Locale& loc) : locale_(&loc) {
@@ -194,18 +204,16 @@ template <typename Char> FMT_FUNC Char decimal_point_impl(locale_ref loc) {
   return std::use_facet<std::numpunct<Char>>(loc.get<std::locale>())
       .decimal_point();
 }
-}  // namespace internal
+}  // namespace detail
 #else
 template <typename Char>
-FMT_FUNC std::string internal::grouping_impl(locale_ref) {
+FMT_FUNC std::string detail::grouping_impl(locale_ref) {
   return "\03";
 }
-template <typename Char>
-FMT_FUNC Char internal::thousands_sep_impl(locale_ref) {
+template <typename Char> FMT_FUNC Char detail::thousands_sep_impl(locale_ref) {
   return FMT_STATIC_THOUSANDS_SEPARATOR;
 }
-template <typename Char>
-FMT_FUNC Char internal::decimal_point_impl(locale_ref) {
+template <typename Char> FMT_FUNC Char detail::decimal_point_impl(locale_ref) {
   return '.';
 }
 #endif
@@ -222,9 +230,9 @@ FMT_FUNC void system_error::init(int err_code, string_view format_str,
   base = std::runtime_error(to_string(buffer));
 }
 
-namespace internal {
+namespace detail {
 
-template <> FMT_FUNC int count_digits<4>(internal::fallback_uintptr n) {
+template <> FMT_FUNC int count_digits<4>(detail::fallback_uintptr n) {
   // fallback_uintptr is always stored in little endian.
   int i = static_cast<int>(sizeof(void*)) - 1;
   while (i > 0 && n.value[i] == 0) --i;
@@ -233,12 +241,27 @@ template <> FMT_FUNC int count_digits<4>(internal::fallback_uintptr n) {
 }
 
 template <typename T>
-const char basic_data<T>::digits[] =
-    "0001020304050607080910111213141516171819"
-    "2021222324252627282930313233343536373839"
-    "4041424344454647484950515253545556575859"
-    "6061626364656667686970717273747576777879"
-    "8081828384858687888990919293949596979899";
+const typename basic_data<T>::digit_pair basic_data<T>::digits[] = {
+    {'0', '0'},  {'0', '1'},  {'0', '2'},  {'0', '3'},  {'0', '4'},
+    {'0', '5'},  {'0', '6'},  {'0', '7'},  {'0', '8'},  {'0', '9'},
+    {'1', '0'},  {'1', '1'},  {'1', '2'},  {'1', '3'},  {'1', '4'},
+    {'1', '5'},  {'1', '6'},  {'1', '7'},  {'1', '8'},  {'1', '9'},
+    {'2', '0'},  {'2', '1'},  {'2', '2'},  {'2', '3'},  {'2', '4'},
+    {'2', '5'},  {'2', '6'},  {'2', '7'},  {'2', '8'},  {'2', '9'},
+    {'3', '0'},  {'3', '1'},  {'3', '2'},  {'3', '3'},  {'3', '4'},
+    {'3', '5'},  {'3', '6'},  {'3', '7'},  {'3', '8'},  {'3', '9'},
+    {'4', '0'},  {'4', '1'},  {'4', '2'},  {'4', '3'},  {'4', '4'},
+    {'4', '5'},  {'4', '6'},  {'4', '7'},  {'4', '8'},  {'4', '9'},
+    {'5', '0'},  {'5', '1'},  {'5', '2'},  {'5', '3'},  {'5', '4'},
+    {'5', '5'},  {'5', '6'},  {'5', '7'},  {'5', '8'},  {'5', '9'},
+    {'6', '0'},  {'6', '1'},  {'6', '2'},  {'6', '3'},  {'6', '4'},
+    {'6', '5'},  {'6', '6'},  {'6', '7'},  {'6', '8'},  {'6', '9'},
+    {'7', '0'},  {'7', '1'},  {'7', '2'},  {'7', '3'},  {'7', '4'},
+    {'7', '5'},  {'7', '6'},  {'7', '7'},  {'7', '8'},  {'7', '9'},
+    {'8', '0'},  {'8', '1'},  {'8', '2'},  {'8', '3'},  {'8', '4'},
+    {'8', '5'},  {'8', '6'},  {'8', '7'},  {'8', '8'},  {'8', '9'},
+    {'9', '0'},  {'9', '1'},  {'9', '2'},  {'9', '3'},  {'9', '4'},
+    {'9', '5'},  {'9', '6'},  {'9', '7'},  {'9', '8'},  {'9', '9'}};
 
 template <typename T>
 const char basic_data<T>::hex_digits[] = "0123456789abcdef";
@@ -317,6 +340,10 @@ const char basic_data<T>::background_color[] = "\x1b[48;2;";
 template <typename T> const char basic_data<T>::reset_color[] = "\x1b[0m";
 template <typename T> const wchar_t basic_data<T>::wreset_color[] = L"\x1b[0m";
 template <typename T> const char basic_data<T>::signs[] = {0, '-', '+', ' '};
+template <typename T>
+const char basic_data<T>::left_padding_shifts[] = {31, 31, 0, 1, 0};
+template <typename T>
+const char basic_data<T>::right_padding_shifts[] = {0, 31, 0, 1, 0};
 
 template <typename T> struct bits {
   static FMT_CONSTEXPR_DECL const int value =
@@ -576,9 +603,10 @@ class bigint {
   void operator=(const bigint&) = delete;
 
   void assign(const bigint& other) {
-    bigits_.resize(other.bigits_.size());
+    auto size = other.bigits_.size();
+    bigits_.resize(size);
     auto data = other.bigits_.data();
-    std::copy(data, data + other.bigits_.size(), bigits_.data());
+    std::copy(data, data + size, make_checked(bigits_.data(), size));
     exp_ = other.exp_;
   }
 
@@ -594,7 +622,7 @@ class bigint {
 
   int num_bigits() const { return static_cast<int>(bigits_.size()) + exp_; }
 
-  bigint& operator<<=(int shift) {
+  FMT_NOINLINE bigint& operator<<=(int shift) {
     assert(shift >= 0);
     exp_ += shift / bigit_bits;
     shift %= bigit_bits;
@@ -1125,7 +1153,7 @@ int snprintf_float(T value, int precision, float_specs specs,
     precision = (precision >= 0 ? precision : 6) - 1;
 
   // Build the format string.
-  enum { max_format_size = 7 };  // Ths longest format is "%#.*Le".
+  enum { max_format_size = 7 };  // The longest format is "%#.*Le".
   char format[max_format_size];
   char* format_ptr = format;
   *format_ptr++ = '%';
@@ -1145,13 +1173,13 @@ int snprintf_float(T value, int precision, float_specs specs,
   for (;;) {
     auto begin = buf.data() + offset;
     auto capacity = buf.capacity() - offset;
-#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+#ifdef FMT_FUZZ
     if (precision > 100000)
       throw std::runtime_error(
           "fuzz mode - avoid large allocation inside snprintf");
 #endif
     // Suppress the warning about a nonliteral format string.
-    // Cannot use auto becase of a bug in MinGW (#1532).
+    // Cannot use auto because of a bug in MinGW (#1532).
     int (*snprintf_ptr)(char*, size_t, const char*, ...) = FMT_SNPRINTF;
     int result = precision >= 0
                      ? snprintf_ptr(begin, capacity, format, precision, value)
@@ -1268,14 +1296,14 @@ FMT_FUNC const char* utf8_decode(const char* buf, uint32_t* c, int* e) {
 
   return next;
 }
-}  // namespace internal
+}  // namespace detail
 
-template <> struct formatter<internal::bigint> {
+template <> struct formatter<detail::bigint> {
   format_parse_context::iterator parse(format_parse_context& ctx) {
     return ctx.begin();
   }
 
-  format_context::iterator format(const internal::bigint& n,
+  format_context::iterator format(const detail::bigint& n,
                                   format_context& ctx) {
     auto out = ctx.out();
     bool first = true;
@@ -1289,12 +1317,12 @@ template <> struct formatter<internal::bigint> {
       out = format_to(out, "{:08x}", value);
     }
     if (n.exp_ > 0)
-      out = format_to(out, "p{}", n.exp_ * internal::bigint::bigit_bits);
+      out = format_to(out, "p{}", n.exp_ * detail::bigint::bigit_bits);
     return out;
   }
 };
 
-FMT_FUNC internal::utf8_to_utf16::utf8_to_utf16(string_view s) {
+FMT_FUNC detail::utf8_to_utf16::utf8_to_utf16(string_view s) {
   auto transcode = [this](const char* p) {
     auto cp = uint32_t();
     auto error = 0;
@@ -1325,7 +1353,7 @@ FMT_FUNC internal::utf8_to_utf16::utf8_to_utf16(string_view s) {
   buffer_.push_back(0);
 }
 
-FMT_FUNC void format_system_error(internal::buffer<char>& out, int error_code,
+FMT_FUNC void format_system_error(detail::buffer<char>& out, int error_code,
                                   string_view message) FMT_NOEXCEPT {
   FMT_TRY {
     memory_buffer buf;
@@ -1333,12 +1361,9 @@ FMT_FUNC void format_system_error(internal::buffer<char>& out, int error_code,
     for (;;) {
       char* system_message = &buf[0];
       int result =
-          internal::safe_strerror(error_code, system_message, buf.size());
+          detail::safe_strerror(error_code, system_message, buf.size());
       if (result == 0) {
-        internal::writer w(out);
-        w.write(message);
-        w.write(": ");
-        w.write(system_message);
+        format_to(std::back_inserter(out), "{}: {}", message, system_message);
         return;
       }
       if (result != ERANGE)
@@ -1350,7 +1375,7 @@ FMT_FUNC void format_system_error(internal::buffer<char>& out, int error_code,
   format_error_code(out, error_code, message);
 }
 
-FMT_FUNC void internal::error_handler::on_error(const char* message) {
+FMT_FUNC void detail::error_handler::on_error(const char* message) {
   FMT_THROW(format_error(message));
 }
 
@@ -1359,14 +1384,39 @@ FMT_FUNC void report_system_error(int error_code,
   report_error(format_system_error, error_code, message);
 }
 
+struct stringifier {
+  template <typename T> FMT_INLINE std::string operator()(T value) const {
+    return to_string(value);
+  }
+  std::string operator()(basic_format_arg<format_context>::handle h) const {
+    memory_buffer buf;
+    detail::buffer<char>& base = buf;
+    format_parse_context parse_ctx({});
+    format_context format_ctx(std::back_inserter(base), {}, {});
+    h.format(parse_ctx, format_ctx);
+    return to_string(buf);
+  }
+};
+
+FMT_FUNC std::string detail::vformat(string_view format_str, format_args args) {
+  if (format_str.size() == 2 && equal2(format_str.data(), "{}")) {
+    auto arg = args.get(0);
+    if (!arg) error_handler().on_error("argument not found");
+    return visit_format_arg(stringifier(), arg);
+  }
+  memory_buffer buffer;
+  detail::vformat_to(buffer, format_str, args);
+  return to_string(buffer);
+}
+
 FMT_FUNC void vprint(std::FILE* f, string_view format_str, format_args args) {
   memory_buffer buffer;
-  internal::vformat_to(buffer, format_str,
-                       basic_format_args<buffer_context<char>>(args));
+  detail::vformat_to(buffer, format_str,
+                     basic_format_args<buffer_context<char>>(args));
 #ifdef _WIN32
   auto fd = _fileno(f);
   if (_isatty(fd)) {
-    internal::utf8_to_utf16 u16(string_view(buffer.data(), buffer.size()));
+    detail::utf8_to_utf16 u16(string_view(buffer.data(), buffer.size()));
     auto written = DWORD();
     if (!WriteConsoleW(reinterpret_cast<HANDLE>(_get_osfhandle(fd)),
                        u16.c_str(), static_cast<DWORD>(u16.size()), &written,
@@ -1376,16 +1426,16 @@ FMT_FUNC void vprint(std::FILE* f, string_view format_str, format_args args) {
     return;
   }
 #endif
-  internal::fwrite_fully(buffer.data(), 1, buffer.size(), f);
+  detail::fwrite_fully(buffer.data(), 1, buffer.size(), f);
 }
 
 #ifdef _WIN32
 // Print assuming legacy (non-Unicode) encoding.
-FMT_FUNC void internal::vprint_mojibake(std::FILE* f, string_view format_str,
-                                        format_args args) {
+FMT_FUNC void detail::vprint_mojibake(std::FILE* f, string_view format_str,
+                                      format_args args) {
   memory_buffer buffer;
-  internal::vformat_to(buffer, format_str,
-                       basic_format_args<buffer_context<char>>(args));
+  detail::vformat_to(buffer, format_str,
+                     basic_format_args<buffer_context<char>>(args));
   fwrite_fully(buffer.data(), 1, buffer.size(), f);
 }
 #endif

include/spdlog/fmt/bundled/locale.h

@@ -14,15 +14,15 @@
 
 FMT_BEGIN_NAMESPACE
 
-namespace internal {
+namespace detail {
 template <typename Char>
 typename buffer_context<Char>::iterator vformat_to(
     const std::locale& loc, buffer<Char>& buf,
     basic_string_view<Char> format_str,
     basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  using range = buffer_range<Char>;
-  return vformat_to<arg_formatter<range>>(buf, to_string_view(format_str), args,
-                                          internal::locale_ref(loc));
+  using af = arg_formatter<typename buffer_context<Char>::iterator, Char>;
+  return vformat_to<af>(std::back_inserter(buf), to_string_view(format_str),
+                        args, detail::locale_ref(loc));
 }
 
 template <typename Char>
@@ -30,43 +30,43 @@ std::basic_string<Char> vformat(
     const std::locale& loc, basic_string_view<Char> format_str,
     basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  internal::vformat_to(loc, buffer, format_str, args);
+  detail::vformat_to(loc, buffer, format_str, args);
   return fmt::to_string(buffer);
 }
-}  // namespace internal
+}  // namespace detail
 
 template <typename S, typename Char = char_t<S>>
 inline std::basic_string<Char> vformat(
     const std::locale& loc, const S& format_str,
     basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  return internal::vformat(loc, to_string_view(format_str), args);
+  return detail::vformat(loc, to_string_view(format_str), args);
 }
 
 template <typename S, typename... Args, typename Char = char_t<S>>
 inline std::basic_string<Char> format(const std::locale& loc,
                                       const S& format_str, Args&&... args) {
-  return internal::vformat(
+  return detail::vformat(
       loc, to_string_view(format_str),
-      internal::make_args_checked<Args...>(format_str, args...));
+      detail::make_args_checked<Args...>(format_str, args...));
 }
 
 template <typename S, typename OutputIt, typename... Args,
           typename Char = enable_if_t<
-              internal::is_output_iterator<OutputIt>::value, char_t<S>>>
+              detail::is_output_iterator<OutputIt>::value, char_t<S>>>
 inline OutputIt vformat_to(
     OutputIt out, const std::locale& loc, const S& format_str,
     format_args_t<type_identity_t<OutputIt>, Char> args) {
-  using range = internal::output_range<OutputIt, Char>;
-  return vformat_to<arg_formatter<range>>(
-      range(out), to_string_view(format_str), args, internal::locale_ref(loc));
+  using af = detail::arg_formatter<OutputIt, Char>;
+  return vformat_to<af>(out, to_string_view(format_str), args,
+                        detail::locale_ref(loc));
 }
 
 template <typename OutputIt, typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value&&
-                            internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt>::value&&
+                            detail::is_string<S>::value)>
 inline OutputIt format_to(OutputIt out, const std::locale& loc,
                           const S& format_str, Args&&... args) {
-  internal::check_format_string<Args...>(format_str);
+  detail::check_format_string<Args...>(format_str);
   using context = format_context_t<OutputIt, char_t<S>>;
   format_arg_store<context, Args...> as{args...};
   return vformat_to(out, loc, to_string_view(format_str),

include/spdlog/fmt/bundled/ostream.h

@@ -14,10 +14,10 @@
 
 FMT_BEGIN_NAMESPACE
 
-template <typename CHar> class basic_printf_parse_context;
+template <typename Char> class basic_printf_parse_context;
 template <typename OutputIt, typename Char> class basic_printf_context;
 
-namespace internal {
+namespace detail {
 
 template <class Char> class formatbuf : public std::basic_streambuf<Char> {
  private:
@@ -80,7 +80,7 @@ template <typename T, typename Char> class is_streamable {
 
 // Write the content of buf to os.
 template <typename Char>
-void write(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
   const Char* buf_data = buf.data();
   using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
   unsigned_streamsize size = buf.size();
@@ -101,8 +101,8 @@ void format_value(buffer<Char>& buf, const T& value,
 #if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
   if (loc) output.imbue(loc.get<std::locale>());
 #endif
-  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
   output << value;
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
   buf.resize(buf.size());
 }
 
@@ -110,7 +110,8 @@ void format_value(buffer<Char>& buf, const T& value,
 template <typename T, typename Char>
 struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
     : private formatter<basic_string_view<Char>, Char> {
-  auto parse(basic_format_parse_context<Char>& ctx) -> decltype(ctx.begin()) {
+  FMT_CONSTEXPR auto parse(basic_format_parse_context<Char>& ctx)
+      -> decltype(ctx.begin()) {
     return formatter<basic_string_view<Char>, Char>::parse(ctx);
   }
   template <typename ParseCtx,
@@ -136,14 +137,14 @@ struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
     return std::copy(buffer.begin(), buffer.end(), ctx.out());
   }
 };
-}  // namespace internal
+}  // namespace detail
 
 template <typename Char>
 void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
             basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  internal::vformat_to(buffer, format_str, args);
-  internal::write(os, buffer);
+  detail::vformat_to(buffer, format_str, args);
+  detail::write_buffer(os, buffer);
 }
 
 /**
@@ -156,10 +157,10 @@ void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
   \endrst
  */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) {
   vprint(os, to_string_view(format_str),
-         internal::make_args_checked<Args...>(format_str, args...));
+         detail::make_args_checked<Args...>(format_str, args...));
 }
 FMT_END_NAMESPACE
 

include/spdlog/fmt/bundled/posix.h

@@ -1,2 +1,2 @@
 #include "os.h"
-#warning "fmt/posix.h is deprecated; use fmt/os.h instead"
+#warning "fmt/posix.h is deprecated; use fmt/os.h instead"

include/spdlog/fmt/bundled/printf.h

@@ -14,7 +14,7 @@
 #include "ostream.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
 // Checks if a value fits in int - used to avoid warnings about comparing
 // signed and unsigned integers.
@@ -90,11 +90,11 @@ template <typename T, typename Context> class arg_converter {
     if (const_check(sizeof(target_type) <= sizeof(int))) {
       // Extra casts are used to silence warnings.
       if (is_signed) {
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<int>(static_cast<target_type>(value)));
       } else {
         using unsigned_type = typename make_unsigned_or_bool<target_type>::type;
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<unsigned>(static_cast<unsigned_type>(value)));
       }
     } else {
@@ -102,9 +102,9 @@ template <typename T, typename Context> class arg_converter {
         // glibc's printf doesn't sign extend arguments of smaller types:
         //   std::printf("%lld", -42);  // prints "4294967254"
         // but we don't have to do the same because it's a UB.
-        arg_ = internal::make_arg<Context>(static_cast<long long>(value));
+        arg_ = detail::make_arg<Context>(static_cast<long long>(value));
       } else {
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<typename make_unsigned_or_bool<U>::type>(value));
       }
     }
@@ -133,7 +133,7 @@ template <typename Context> class char_converter {
 
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   void operator()(T value) {
-    arg_ = internal::make_arg<Context>(
+    arg_ = detail::make_arg<Context>(
         static_cast<typename Context::char_type>(value));
   }
 
@@ -141,6 +141,13 @@ template <typename Context> class char_converter {
   void operator()(T) {}  // No conversion needed for non-integral types.
 };
 
+// An argument visitor that return a pointer to a C string if argument is a
+// string or null otherwise.
+template <typename Char> struct get_cstring {
+  template <typename T> const Char* operator()(T) { return nullptr; }
+  const Char* operator()(const Char* s) { return s; }
+};
+
 // Checks if an argument is a valid printf width specifier and sets
 // left alignment if it is negative.
 template <typename Char> class printf_width_handler {
@@ -155,7 +162,7 @@ template <typename Char> class printf_width_handler {
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   unsigned operator()(T value) {
     auto width = static_cast<uint32_or_64_or_128_t<T>>(value);
-    if (internal::is_negative(value)) {
+    if (detail::is_negative(value)) {
       specs_.align = align::left;
       width = 0 - width;
     }
@@ -172,22 +179,20 @@ template <typename Char> class printf_width_handler {
 };
 
 template <typename Char, typename Context>
-void printf(buffer<Char>& buf, basic_string_view<Char> format,
-            basic_format_args<Context> args) {
+void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
+             basic_format_args<Context> args) {
   Context(std::back_inserter(buf), format, args).format();
 }
+}  // namespace detail
 
-template <typename OutputIt, typename Char, typename Context>
-internal::truncating_iterator<OutputIt> printf(
-    internal::truncating_iterator<OutputIt> it, basic_string_view<Char> format,
-    basic_format_args<Context> args) {
-  return Context(it, format, args).format();
+// For printing into memory_buffer.
+template <typename Char, typename Context>
+FMT_DEPRECATED void printf(detail::buffer<Char>& buf,
+                           basic_string_view<Char> format,
+                           basic_format_args<Context> args) {
+  return detail::vprintf(buf, format, args);
 }
-}  // namespace internal
-
-using internal::printf;  // For printing into memory_buffer.
-
-template <typename Range> class printf_arg_formatter;
+using detail::vprintf;
 
 template <typename Char>
 class basic_printf_parse_context : public basic_format_parse_context<Char> {
@@ -200,15 +205,15 @@ template <typename OutputIt, typename Char> class basic_printf_context;
   The ``printf`` argument formatter.
   \endrst
  */
-template <typename Range>
-class printf_arg_formatter : public internal::arg_formatter_base<Range> {
+template <typename OutputIt, typename Char>
+class printf_arg_formatter : public detail::arg_formatter_base<OutputIt, Char> {
  public:
-  using iterator = typename Range::iterator;
+  using iterator = OutputIt;
 
  private:
-  using char_type = typename Range::value_type;
-  using base = internal::arg_formatter_base<Range>;
-  using context_type = basic_printf_context<iterator, char_type>;
+  using char_type = Char;
+  using base = detail::arg_formatter_base<OutputIt, Char>;
+  using context_type = basic_printf_context<OutputIt, Char>;
 
   context_type& context_;
 
@@ -233,9 +238,9 @@ class printf_arg_formatter : public internal::arg_formatter_base<Range> {
     \endrst
    */
   printf_arg_formatter(iterator iter, format_specs& specs, context_type& ctx)
-      : base(Range(iter), &specs, internal::locale_ref()), context_(ctx) {}
+      : base(iter, &specs, detail::locale_ref()), context_(ctx) {}
 
-  template <typename T, FMT_ENABLE_IF(fmt::internal::is_integral<T>::value)>
+  template <typename T, FMT_ENABLE_IF(fmt::detail::is_integral<T>::value)>
   iterator operator()(T value) {
     // MSVC2013 fails to compile separate overloads for bool and char_type so
     // use std::is_same instead.
@@ -250,7 +255,11 @@ class printf_arg_formatter : public internal::arg_formatter_base<Range> {
         return (*this)(static_cast<int>(value));
       fmt_specs.sign = sign::none;
       fmt_specs.alt = false;
-      fmt_specs.align = align::right;
+      fmt_specs.fill[0] = ' ';  // Ignore '0' flag for char types.
+      // align::numeric needs to be overwritten here since the '0' flag is
+      // ignored for non-numeric types
+      if (fmt_specs.align == align::none || fmt_specs.align == align::numeric)
+        fmt_specs.align = align::right;
       return base::operator()(value);
     } else {
       return base::operator()(value);
@@ -316,12 +325,14 @@ template <typename T> struct printf_formatter {
 
   template <typename FormatContext>
   auto format(const T& value, FormatContext& ctx) -> decltype(ctx.out()) {
-    internal::format_value(internal::get_container(ctx.out()), value);
+    detail::format_value(detail::get_container(ctx.out()), value);
     return ctx.out();
   }
 };
 
-/** This template formats data and writes the output to a writer. */
+/**
+ This template formats data and writes the output through an output iterator.
+ */
 template <typename OutputIt, typename Char> class basic_printf_context {
  public:
   /** The character type for the output. */
@@ -351,9 +362,8 @@ template <typename OutputIt, typename Char> class basic_printf_context {
  public:
   /**
    \rst
-   Constructs a ``printf_context`` object. References to the arguments and
-   the writer are stored in the context object so make sure they have
-   appropriate lifetimes.
+   Constructs a ``printf_context`` object. References to the arguments are
+   stored in the context object so make sure they have appropriate lifetimes.
    \endrst
    */
   basic_printf_context(OutputIt out, basic_string_view<char_type> format_str,
@@ -363,7 +373,7 @@ template <typename OutputIt, typename Char> class basic_printf_context {
   OutputIt out() { return out_; }
   void advance_to(OutputIt it) { out_ = it; }
 
-  internal::locale_ref locale() { return {}; }
+  detail::locale_ref locale() { return {}; }
 
   format_arg arg(int id) const { return args_.get(id); }
 
@@ -374,7 +384,7 @@ template <typename OutputIt, typename Char> class basic_printf_context {
   }
 
   /** Formats stored arguments and writes the output to the range. */
-  template <typename ArgFormatter = printf_arg_formatter<buffer_range<Char>>>
+  template <typename ArgFormatter = printf_arg_formatter<OutputIt, Char>>
   OutputIt format();
 };
 
@@ -394,7 +404,9 @@ void basic_printf_context<OutputIt, Char>::parse_flags(format_specs& specs,
       specs.fill[0] = '0';
       break;
     case ' ':
-      specs.sign = sign::space;
+      if (specs.sign != sign::plus) {
+        specs.sign = sign::space;
+      }
       break;
     case '#':
       specs.alt = true;
@@ -412,7 +424,7 @@ basic_printf_context<OutputIt, Char>::get_arg(int arg_index) {
     arg_index = parse_ctx_.next_arg_id();
   else
     parse_ctx_.check_arg_id(--arg_index);
-  return internal::get_arg(*this, arg_index);
+  return detail::get_arg(*this, arg_index);
 }
 
 template <typename OutputIt, typename Char>
@@ -424,7 +436,7 @@ int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
   if (c >= '0' && c <= '9') {
     // Parse an argument index (if followed by '$') or a width possibly
     // preceded with '0' flag(s).
-    internal::error_handler eh;
+    detail::error_handler eh;
     int value = parse_nonnegative_int(it, end, eh);
     if (it != end && *it == '$') {  // value is an argument index
       ++it;
@@ -443,12 +455,12 @@ int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
   // Parse width.
   if (it != end) {
     if (*it >= '0' && *it <= '9') {
-      internal::error_handler eh;
+      detail::error_handler eh;
       specs.width = parse_nonnegative_int(it, end, eh);
     } else if (*it == '*') {
       ++it;
       specs.width = static_cast<int>(visit_format_arg(
-          internal::printf_width_handler<char_type>(specs), get_arg()));
+          detail::printf_width_handler<char_type>(specs), get_arg()));
     }
   }
   return arg_index;
@@ -476,38 +488,52 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
 
     // Parse argument index, flags and width.
     int arg_index = parse_header(it, end, specs);
-    if (arg_index == 0) on_error("argument index out of range");
+    if (arg_index == 0) on_error("argument not found");
 
     // Parse precision.
     if (it != end && *it == '.') {
       ++it;
       c = it != end ? *it : 0;
       if ('0' <= c && c <= '9') {
-        internal::error_handler eh;
+        detail::error_handler eh;
         specs.precision = parse_nonnegative_int(it, end, eh);
       } else if (c == '*') {
         ++it;
         specs.precision = static_cast<int>(
-            visit_format_arg(internal::printf_precision_handler(), get_arg()));
+            visit_format_arg(detail::printf_precision_handler(), get_arg()));
       } else {
         specs.precision = 0;
       }
     }
 
     format_arg arg = get_arg(arg_index);
-    if (specs.alt && visit_format_arg(internal::is_zero_int(), arg))
+    // For d, i, o, u, x, and X conversion specifiers, if a precision is
+    // specified, the '0' flag is ignored
+    if (specs.precision >= 0 && arg.is_integral())
+      specs.fill[0] =
+          ' ';  // Ignore '0' flag for non-numeric types or if '-' present.
+    if (specs.precision >= 0 && arg.type() == detail::type::cstring_type) {
+      auto str = visit_format_arg(detail::get_cstring<Char>(), arg);
+      auto str_end = str + specs.precision;
+      auto nul = std::find(str, str_end, Char());
+      arg = detail::make_arg<basic_printf_context>(basic_string_view<Char>(
+          str,
+          detail::to_unsigned(nul != str_end ? nul - str : specs.precision)));
+    }
+    if (specs.alt && visit_format_arg(detail::is_zero_int(), arg))
       specs.alt = false;
     if (specs.fill[0] == '0') {
-      if (arg.is_arithmetic())
+      if (arg.is_arithmetic() && specs.align != align::left)
         specs.align = align::numeric;
       else
-        specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types.
+        specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types or if '-'
+                              // flag is also present.
     }
 
     // Parse length and convert the argument to the required type.
     c = it != end ? *it++ : 0;
     char_type t = it != end ? *it : 0;
-    using internal::convert_arg;
+    using detail::convert_arg;
     switch (c) {
     case 'h':
       if (t == 'h') {
@@ -531,7 +557,7 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
       convert_arg<intmax_t>(arg, t);
       break;
     case 'z':
-      convert_arg<std::size_t>(arg, t);
+      convert_arg<size_t>(arg, t);
       break;
     case 't':
       convert_arg<std::ptrdiff_t>(arg, t);
@@ -556,7 +582,7 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
         specs.type = 'd';
         break;
       case 'c':
-        visit_format_arg(internal::char_converter<basic_printf_context>(arg),
+        visit_format_arg(detail::char_converter<basic_printf_context>(arg),
                          arg);
         break;
       }
@@ -565,15 +591,14 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
     start = it;
 
     // Format argument.
-    visit_format_arg(ArgFormatter(out, specs, *this), arg);
+    out = visit_format_arg(ArgFormatter(out, specs, *this), arg);
   }
   return std::copy(start, it, out);
 }
 
 template <typename Char>
 using basic_printf_context_t =
-    basic_printf_context<std::back_insert_iterator<internal::buffer<Char>>,
-                         Char>;
+    basic_printf_context<std::back_insert_iterator<detail::buffer<Char>>, Char>;
 
 using printf_context = basic_printf_context_t<char>;
 using wprintf_context = basic_printf_context_t<wchar_t>;
@@ -610,7 +635,7 @@ inline std::basic_string<Char> vsprintf(
     const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
+  vprintf(buffer, to_string_view(format), args);
   return to_string(buffer);
 }
 
@@ -624,7 +649,7 @@ inline std::basic_string<Char> vsprintf(
   \endrst
 */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 inline std::basic_string<Char> sprintf(const S& format, const Args&... args) {
   using context = basic_printf_context_t<Char>;
   return vsprintf(to_string_view(format), make_format_args<context>(args...));
@@ -635,8 +660,8 @@ inline int vfprintf(
     std::FILE* f, const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
-  std::size_t size = buffer.size();
+  vprintf(buffer, to_string_view(format), args);
+  size_t size = buffer.size();
   return std::fwrite(buffer.data(), sizeof(Char), size, f) < size
              ? -1
              : static_cast<int>(size);
@@ -652,7 +677,7 @@ inline int vfprintf(
   \endrst
  */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 inline int fprintf(std::FILE* f, const S& format, const Args&... args) {
   using context = basic_printf_context_t<Char>;
   return vfprintf(f, to_string_view(format),
@@ -676,7 +701,7 @@ inline int vprintf(
   \endrst
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
 inline int printf(const S& format_str, const Args&... args) {
   using context = basic_printf_context_t<char_t<S>>;
   return vprintf(to_string_view(format_str),
@@ -688,8 +713,8 @@ inline int vfprintf(
     std::basic_ostream<Char>& os, const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
-  internal::write(os, buffer);
+  vprintf(buffer, to_string_view(format), args);
+  detail::write_buffer(os, buffer);
   return static_cast<int>(buffer.size());
 }
 
@@ -698,7 +723,7 @@ template <typename ArgFormatter, typename Char,
           typename Context =
               basic_printf_context<typename ArgFormatter::iterator, Char>>
 typename ArgFormatter::iterator vprintf(
-    internal::buffer<Char>& out, basic_string_view<Char> format_str,
+    detail::buffer<Char>& out, basic_string_view<Char> format_str,
     basic_format_args<type_identity_t<Context>> args) {
   typename ArgFormatter::iterator iter(out);
   Context(iter, format_str, args).template format<ArgFormatter>();

include/spdlog/fmt/bundled/ranges.h

@@ -33,7 +33,7 @@ template <typename Char> struct formatting_base {
 
 template <typename Char, typename Enable = void>
 struct formatting_range : formatting_base<Char> {
-  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
+  static FMT_CONSTEXPR_DECL const size_t range_length_limit =
       FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
                                       // range.
   Char prefix;
@@ -54,7 +54,7 @@ struct formatting_tuple : formatting_base<Char> {
   static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
 };
 
-namespace internal {
+namespace detail {
 
 template <typename RangeT, typename OutputIterator>
 OutputIterator copy(const RangeT& range, OutputIterator out) {
@@ -118,26 +118,24 @@ template <typename T> class is_tuple_like_ {
 #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
 template <typename T, T... N>
 using integer_sequence = std::integer_sequence<T, N...>;
-template <std::size_t... N> using index_sequence = std::index_sequence<N...>;
-template <std::size_t N>
-using make_index_sequence = std::make_index_sequence<N>;
+template <size_t... N> using index_sequence = std::index_sequence<N...>;
+template <size_t N> using make_index_sequence = std::make_index_sequence<N>;
 #else
 template <typename T, T... N> struct integer_sequence {
   using value_type = T;
 
-  static FMT_CONSTEXPR std::size_t size() { return sizeof...(N); }
+  static FMT_CONSTEXPR size_t size() { return sizeof...(N); }
 };
 
-template <std::size_t... N>
-using index_sequence = integer_sequence<std::size_t, N...>;
+template <size_t... N> using index_sequence = integer_sequence<size_t, N...>;
 
-template <typename T, std::size_t N, T... Ns>
+template <typename T, size_t N, T... Ns>
 struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
 template <typename T, T... Ns>
 struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
 
-template <std::size_t N>
-using make_index_sequence = make_integer_sequence<std::size_t, N>;
+template <size_t N>
+using make_index_sequence = make_integer_sequence<size_t, N>;
 #endif
 
 template <class Tuple, class F, size_t... Is>
@@ -185,11 +183,11 @@ FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
   return add_space ? L" '{}'" : L"'{}'";
 }
 
-}  // namespace internal
+}  // namespace detail
 
 template <typename T> struct is_tuple_like {
   static FMT_CONSTEXPR_DECL const bool value =
-      internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
+      detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
 };
 
 template <typename TupleT, typename Char>
@@ -202,17 +200,17 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
         if (formatting.add_prepostfix_space) {
           *out++ = ' ';
         }
-        out = internal::copy(formatting.delimiter, out);
+        out = detail::copy(formatting.delimiter, out);
       }
       out = format_to(out,
-                      internal::format_str_quoted(
+                      detail::format_str_quoted(
                           (formatting.add_delimiter_spaces && i > 0), v),
                       v);
       ++i;
     }
 
     formatting_tuple<Char>& formatting;
-    std::size_t& i;
+    size_t& i;
     typename std::add_lvalue_reference<decltype(
         std::declval<FormatContext>().out())>::type out;
   };
@@ -228,14 +226,14 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
   template <typename FormatContext = format_context>
   auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
     auto out = ctx.out();
-    std::size_t i = 0;
-    internal::copy(formatting.prefix, out);
+    size_t i = 0;
+    detail::copy(formatting.prefix, out);
 
-    internal::for_each(values, format_each<FormatContext>{formatting, i, out});
+    detail::for_each(values, format_each<FormatContext>{formatting, i, out});
     if (formatting.add_prepostfix_space) {
       *out++ = ' ';
     }
-    internal::copy(formatting.postfix, out);
+    detail::copy(formatting.postfix, out);
 
     return ctx.out();
   }
@@ -243,10 +241,9 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
 
 template <typename T, typename Char> struct is_range {
   static FMT_CONSTEXPR_DECL const bool value =
-      internal::is_range_<T>::value &&
-      !internal::is_like_std_string<T>::value &&
+      detail::is_range_<T>::value && !detail::is_like_std_string<T>::value &&
       !std::is_convertible<T, std::basic_string<Char>>::value &&
-      !std::is_constructible<internal::std_string_view<Char>, T>::value;
+      !std::is_constructible<detail::std_string_view<Char>, T>::value;
 };
 
 template <typename RangeT, typename Char>
@@ -262,15 +259,17 @@ struct formatter<RangeT, Char,
   template <typename FormatContext>
   typename FormatContext::iterator format(const RangeT& values,
                                           FormatContext& ctx) {
-    auto out = internal::copy(formatting.prefix, ctx.out());
-    std::size_t i = 0;
-    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
+    auto out = detail::copy(formatting.prefix, ctx.out());
+    size_t i = 0;
+    auto it = values.begin();
+    auto end = values.end();
+    for (; it != end; ++it) {
       if (i > 0) {
         if (formatting.add_prepostfix_space) *out++ = ' ';
-        out = internal::copy(formatting.delimiter, out);
+        out = detail::copy(formatting.delimiter, out);
       }
       out = format_to(out,
-                      internal::format_str_quoted(
+                      detail::format_str_quoted(
                           (formatting.add_delimiter_spaces && i > 0), *it),
                       *it);
       if (++i > formatting.range_length_limit) {
@@ -279,11 +278,11 @@ struct formatter<RangeT, Char,
       }
     }
     if (formatting.add_prepostfix_space) *out++ = ' ';
-    return internal::copy(formatting.postfix, out);
+    return detail::copy(formatting.postfix, out);
   }
 };
 
-template <typename Char, typename... T> struct tuple_arg_join : internal::view {
+template <typename Char, typename... T> struct tuple_arg_join : detail::view {
   const std::tuple<T...>& tuple;
   basic_string_view<Char> sep;
 
@@ -301,14 +300,14 @@ struct formatter<tuple_arg_join<Char, T...>, Char> {
   template <typename FormatContext>
   typename FormatContext::iterator format(
       const tuple_arg_join<Char, T...>& value, FormatContext& ctx) {
-    return format(value, ctx, internal::make_index_sequence<sizeof...(T)>{});
+    return format(value, ctx, detail::make_index_sequence<sizeof...(T)>{});
   }
 
  private:
   template <typename FormatContext, size_t... N>
   typename FormatContext::iterator format(
       const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
-      internal::index_sequence<N...>) {
+      detail::index_sequence<N...>) {
     return format_args(value, ctx, std::get<N>(value.tuple)...);
   }
 
@@ -371,14 +370,14 @@ FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
   \endrst
  */
 template <typename T>
-arg_join<internal::iterator_t<const std::initializer_list<T>>, char> join(
-    std::initializer_list<T> list, string_view sep) {
+arg_join<const T*, const T*, char> join(std::initializer_list<T> list,
+                                        string_view sep) {
   return join(std::begin(list), std::end(list), sep);
 }
 
 template <typename T>
-arg_join<internal::iterator_t<const std::initializer_list<T>>, wchar_t> join(
-    std::initializer_list<T> list, wstring_view sep) {
+arg_join<const T*, const T*, wchar_t> join(std::initializer_list<T> list,
+                                           wstring_view sep) {
   return join(std::begin(list), std::end(list), sep);
 }
 

include/spdlog/fmt/fmt.h

@@ -14,6 +14,8 @@
 #ifndef FMT_USE_WINDOWS_H
 #define FMT_USE_WINDOWS_H 0
 #endif
+// enable the 'n' flag in for backward compatibility with fmt 6.x
+#define FMT_DEPRECATED_N_SPECIFIER
 #include <spdlog/fmt/bundled/core.h>
 #include <spdlog/fmt/bundled/format.h>
 #else // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib

include/spdlog/logger.h

@@ -170,9 +170,9 @@ public:
     }
 
     // T cannot be statically converted to string_view or wstring_view
-    template<class T,
-        typename std::enable_if_t<
-            !std::is_convertible<const T &, spdlog::string_view_t>::value && !is_convertible_to_wstring_view<const T &>::value, int> = 0>
+    template<class T, typename std::enable_if<!std::is_convertible<const T &, spdlog::string_view_t>::value &&
+                                                  !is_convertible_to_wstring_view<const T &>::value,
+                          int>::type = 0>
     void log(source_loc loc, level::level_enum lvl, const T &msg)
     {
         log(loc, lvl, "{}", msg);

include/spdlog/spdlog-inl.h

@@ -0,0 +1,125 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#ifndef SPDLOG_HEADER_ONLY
+#include <spdlog/spdlog.h>
+#endif
+
+#include <spdlog/common.h>
+#include <spdlog/pattern_formatter.h>
+
+namespace spdlog {
+
+SPDLOG_INLINE void initialize_logger(std::shared_ptr<logger> logger)
+{
+    details::registry::instance().initialize_logger(std::move(logger));
+}
+
+SPDLOG_INLINE std::shared_ptr<logger> get(const std::string &name)
+{
+    return details::registry::instance().get(name);
+}
+
+SPDLOG_INLINE void set_formatter(std::unique_ptr<spdlog::formatter> formatter)
+{
+    details::registry::instance().set_formatter(std::move(formatter));
+}
+
+SPDLOG_INLINE void set_pattern(std::string pattern, pattern_time_type time_type)
+{
+    set_formatter(std::unique_ptr<spdlog::formatter>(new pattern_formatter(std::move(pattern), time_type)));
+}
+
+SPDLOG_INLINE void enable_backtrace(size_t n_messages)
+{
+    details::registry::instance().enable_backtrace(n_messages);
+}
+
+SPDLOG_INLINE void disable_backtrace()
+{
+    details::registry::instance().disable_backtrace();
+}
+
+SPDLOG_INLINE void dump_backtrace()
+{
+    default_logger_raw()->dump_backtrace();
+}
+
+SPDLOG_INLINE level::level_enum get_level()
+{
+    return default_logger_raw()->level();
+}
+
+SPDLOG_INLINE bool should_log(level::level_enum log_level)
+{
+    return default_logger_raw()->should_log(log_level);
+}
+
+SPDLOG_INLINE void set_level(level::level_enum log_level)
+{
+    details::registry::instance().set_level(log_level);
+}
+
+SPDLOG_INLINE void flush_on(level::level_enum log_level)
+{
+    details::registry::instance().flush_on(log_level);
+}
+
+SPDLOG_INLINE void flush_every(std::chrono::seconds interval)
+{
+    details::registry::instance().flush_every(interval);
+}
+
+SPDLOG_INLINE void set_error_handler(void (*handler)(const std::string &msg))
+{
+    details::registry::instance().set_error_handler(handler);
+}
+
+SPDLOG_INLINE void register_logger(std::shared_ptr<logger> logger)
+{
+    details::registry::instance().register_logger(std::move(logger));
+}
+
+SPDLOG_INLINE void apply_all(const std::function<void(std::shared_ptr<logger>)> &fun)
+{
+    details::registry::instance().apply_all(fun);
+}
+
+SPDLOG_INLINE void drop(const std::string &name)
+{
+    details::registry::instance().drop(name);
+}
+
+SPDLOG_INLINE void drop_all()
+{
+    details::registry::instance().drop_all();
+}
+
+SPDLOG_INLINE void shutdown()
+{
+    details::registry::instance().shutdown();
+}
+
+SPDLOG_INLINE void set_automatic_registration(bool automatic_registration)
+{
+    details::registry::instance().set_automatic_registration(automatic_registration);
+}
+
+SPDLOG_INLINE std::shared_ptr<spdlog::logger> default_logger()
+{
+    return details::registry::instance().default_logger();
+}
+
+SPDLOG_INLINE spdlog::logger *default_logger_raw()
+{
+    return details::registry::instance().get_default_raw();
+}
+
+SPDLOG_INLINE void set_default_logger(std::shared_ptr<spdlog::logger> default_logger)
+{
+    details::registry::instance().set_default_logger(std::move(default_logger));
+}
+
+} // namespace spdlog

include/spdlog/stopwatch.h

@@ -0,0 +1,61 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/fmt/fmt.h>
+
+// Stopwatch support for spdlog  (using std::chrono::high_resolution_clock).
+// Displays elapsed seconds since construction as double.
+//
+// Usage:
+//
+// spdlog::stopwatch sw;
+// ...
+// spdlog::debug("Elapsed: {} seconds", sw);    =>  "Elapsed 0.005116733 seconds"
+// spdlog::info("Elapsed: {:.6} seconds", sw);  =>  "Elapsed 0.005163 seconds"
+//
+//
+// If other units are needed (e.g. millis instead of double), include "fmt/chrono.h" and use "duration_cast<..>(sw.elapsed())":
+//
+// #include <fmt/chrono.h>
+//..
+// using std::chrono::duration_cast;
+// using std::chrono::milliseconds;
+// spdlog::info("Elapsed {}", duration_cast<milliseconds>(sw.elapsed())); => "Elapsed 5ms"
+
+namespace spdlog {
+class stopwatch
+{
+    using clock = std::chrono::high_resolution_clock;
+    std::chrono::time_point<clock> start_tp_;
+
+public:
+    stopwatch()
+        : start_tp_{clock::now()}
+    {}
+
+    std::chrono::duration<double> elapsed() const
+    {
+        return std::chrono::duration<double>(clock::now() - start_tp_);
+    }
+
+    void reset()
+    {
+        start_tp_ = clock ::now();
+    }
+};
+} // namespace spdlog
+
+// Support for fmt formatting  (e.g. "{:012.9}" or just "{}")
+namespace fmt {
+template<>
+struct formatter<spdlog::stopwatch> : formatter<double>
+{
+    template<typename FormatContext>
+    auto format(const spdlog::stopwatch &sw, FormatContext &ctx) -> decltype(ctx.out())
+    {
+        return formatter<double>::format(sw.elapsed().count(), ctx);
+    }
+};
+} // namespace fmt

src/fmt.cpp

@@ -6,12 +6,12 @@
 #include <spdlog/fmt/bundled/format-inl.h>
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
 template<typename T>
 int format_float(char *buf, std::size_t size, const char *format, int precision, T value)
 {
-#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+#ifdef FMT_FUZZ
     if (precision > 100000)
         throw std::runtime_error("fuzz mode - avoid large allocation inside snprintf");
 #endif
@@ -19,167 +19,41 @@ int format_float(char *buf, std::size_t size, const char *format, int precision,
     int (*snprintf_ptr)(char *, size_t, const char *, ...) = FMT_SNPRINTF;
     return precision < 0 ? snprintf_ptr(buf, size, format, value) : snprintf_ptr(buf, size, format, precision, value);
 }
-struct sprintf_specs
-{
-    int precision;
-    char type;
-    bool alt : 1;
+} // namespace detail
 
-    template<typename Char>
-    constexpr sprintf_specs(basic_format_specs<Char> specs)
-        : precision(specs.precision)
-        , type(specs.type)
-        , alt(specs.alt)
-    {}
-
-    constexpr bool has_precision() const
-    {
-        return precision >= 0;
-    }
-};
-
-// This is deprecated and is kept only to preserve ABI compatibility.
-template<typename Double>
-char *sprintf_format(Double value, internal::buffer<char> &buf, sprintf_specs specs)
-{
-    // Buffer capacity must be non-zero, otherwise MSVC's vsnprintf_s will fail.
-    FMT_ASSERT(buf.capacity() != 0, "empty buffer");
-
-    // Build format string.
-    enum
-    {
-        max_format_size = 10
-    }; // longest format: %#-*.*Lg
-    char format[max_format_size];
-    char *format_ptr = format;
-    *format_ptr++ = '%';
-    if (specs.alt || !specs.type)
-        *format_ptr++ = '#';
-    if (specs.precision >= 0)
-    {
-        *format_ptr++ = '.';
-        *format_ptr++ = '*';
-    }
-    if (std::is_same<Double, long double>::value)
-        *format_ptr++ = 'L';
-
-    char type = specs.type;
-
-    if (type == '%')
-        type = 'f';
-    else if (type == 0 || type == 'n')
-        type = 'g';
-#if FMT_MSC_VER
-    if (type == 'F')
-    {
-        // MSVC's printf doesn't support 'F'.
-        type = 'f';
-    }
-#endif
-    *format_ptr++ = type;
-    *format_ptr = '\0';
-
-    // Format using snprintf.
-    char *start = nullptr;
-    char *decimal_point_pos = nullptr;
-    for (;;)
-    {
-        std::size_t buffer_size = buf.capacity();
-        start = &buf[0];
-        int result = format_float(start, buffer_size, format, specs.precision, value);
-        if (result >= 0)
-        {
-            unsigned n = internal::to_unsigned(result);
-            if (n < buf.capacity())
-            {
-                // Find the decimal point.
-                auto p = buf.data(), end = p + n;
-                if (*p == '+' || *p == '-')
-                    ++p;
-                if (specs.type != 'a' && specs.type != 'A')
-                {
-                    while (p < end && *p >= '0' && *p <= '9')
-                        ++p;
-                    if (p < end && *p != 'e' && *p != 'E')
-                    {
-                        decimal_point_pos = p;
-                        if (!specs.type)
-                        {
-                            // Keep only one trailing zero after the decimal point.
-                            ++p;
-                            if (*p == '0')
-                                ++p;
-                            while (p != end && *p >= '1' && *p <= '9')
-                                ++p;
-                            char *where = p;
-                            while (p != end && *p == '0')
-                                ++p;
-                            if (p == end || *p < '0' || *p > '9')
-                            {
-                                if (p != end)
-                                    std::memmove(where, p, to_unsigned(end - p));
-                                n -= static_cast<unsigned>(p - where);
-                            }
-                        }
-                    }
-                }
-                buf.resize(n);
-                break; // The buffer is large enough - continue with formatting.
-            }
-            buf.reserve(n + 1);
-        }
-        else
-        {
-            // If result is negative we ask to increase the capacity by at least 1,
-            // but as std::vector, the buffer grows exponentially.
-            buf.reserve(buf.capacity() + 1);
-        }
-    }
-    return decimal_point_pos;
-}
-} // namespace internal
-
-template FMT_API char *internal::sprintf_format(double, internal::buffer<char> &, sprintf_specs);
-template FMT_API char *internal::sprintf_format(long double, internal::buffer<char> &, sprintf_specs);
-
-template struct FMT_INSTANTIATION_DEF_API internal::basic_data<void>;
+template struct FMT_INSTANTIATION_DEF_API detail::basic_data<void>;
 
 // Workaround a bug in MSVC2013 that prevents instantiation of format_float.
-int (*instantiate_format_float)(double, int, internal::float_specs, internal::buffer<char> &) = internal::format_float;
+int (*instantiate_format_float)(double, int, detail::float_specs, detail::buffer<char> &) = detail::format_float;
 
 #ifndef FMT_STATIC_THOUSANDS_SEPARATOR
-template FMT_API internal::locale_ref::locale_ref(const std::locale &loc);
-template FMT_API std::locale internal::locale_ref::get<std::locale>() const;
+template FMT_API detail::locale_ref::locale_ref(const std::locale &loc);
+template FMT_API std::locale detail::locale_ref::get<std::locale>() const;
 #endif
 
 // Explicit instantiations for char.
 
-template FMT_API std::string internal::grouping_impl<char>(locale_ref);
-template FMT_API char internal::thousands_sep_impl(locale_ref);
-template FMT_API char internal::decimal_point_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<char>(locale_ref);
+template FMT_API char detail::thousands_sep_impl(locale_ref);
+template FMT_API char detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::buffer<char>::append(const char *, const char *);
+template FMT_API void detail::buffer<char>::append(const char *, const char *);
 
-template FMT_API void internal::arg_map<format_context>::init(const basic_format_args<format_context> &args);
+template FMT_API FMT_BUFFER_CONTEXT(char)::iterator detail::vformat_to(
+    detail::buffer<char> &, string_view, basic_format_args<FMT_BUFFER_CONTEXT(char)>);
 
-template FMT_API std::string internal::vformat<char>(string_view, basic_format_args<format_context>);
-
-template FMT_API format_context::iterator internal::vformat_to(internal::buffer<char> &, string_view, basic_format_args<format_context>);
-
-template FMT_API int internal::snprintf_float(double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::snprintf_float(long double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::format_float(double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::format_float(long double, int, internal::float_specs, internal::buffer<char> &);
+template FMT_API int detail::snprintf_float(double, int, detail::float_specs, detail::buffer<char> &);
+template FMT_API int detail::snprintf_float(long double, int, detail::float_specs, detail::buffer<char> &);
+template FMT_API int detail::format_float(double, int, detail::float_specs, detail::buffer<char> &);
+template FMT_API int detail::format_float(long double, int, detail::float_specs, detail::buffer<char> &);
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API std::string internal::grouping_impl<wchar_t>(locale_ref);
-template FMT_API wchar_t internal::thousands_sep_impl(locale_ref);
-template FMT_API wchar_t internal::decimal_point_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<wchar_t>(locale_ref);
+template FMT_API wchar_t detail::thousands_sep_impl(locale_ref);
+template FMT_API wchar_t detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::buffer<wchar_t>::append(const wchar_t *, const wchar_t *);
-
-template FMT_API std::wstring internal::vformat<wchar_t>(wstring_view, basic_format_args<wformat_context>);
+template FMT_API void detail::buffer<wchar_t>::append(const wchar_t *, const wchar_t *);
 FMT_END_NAMESPACE
 
 #endif // !SPDLOG_FMT_EXTERNAL

src/pattern_formatter.cpp

@@ -1240,9 +1240,24 @@ void pattern_formatter::handle_flag_(char flag, details::padding_info padding)
 
     default: // Unknown flag appears as is
         auto unknown_flag = std::make_unique<details::aggregate_formatter>();
-        unknown_flag->add_ch('%');
-        unknown_flag->add_ch(flag);
-        formatters_.push_back((std::move(unknown_flag)));
+
+        if (!padding.truncate_)
+        {
+            unknown_flag->add_ch('%');
+            unknown_flag->add_ch(flag);
+            formatters_.push_back((std::move(unknown_flag)));
+        }
+            // fix issue #1617 (prev char was '!' and should have been treated as funcname flag instead of truncating flag)
+            // spdlog::set_pattern("[%10!] %v") => "[      main] some message"
+            // spdlog::set_pattern("[%3!!] %v") => "[mai] some message"
+        else
+        {
+            padding.truncate_ = false;
+            formatters_.push_back(std::make_unique<details::source_funcname_formatter<Padder>>(padding));
+            unknown_flag->add_ch(flag);
+            formatters_.push_back((std::move(unknown_flag)));
+        }
+
         break;
     }
 }

tests/CMakeLists.txt

@@ -1,5 +1,4 @@
-cmake_minimum_required(VERSION 3.2)
-
+cmake_minimum_required(VERSION 3.10)
 project(spdlog_utests CXX)
 
 if (NOT TARGET spdlog)
@@ -32,7 +31,8 @@ set(SPDLOG_UTESTS_SOURCES
         test_stdout_api.cpp
         test_create_dir.cpp
         test_cfg.cpp
-        test_time_point.cpp)
+        test_time_point.cpp
+        test_stopwatch.cpp)
 
 if (NOT SPDLOG_NO_EXCEPTIONS)
     list(APPEND SPDLOG_UTESTS_SOURCES test_errors.cpp)

tests/test_mpmc_q.cpp

@@ -10,7 +10,7 @@ static milliseconds millis_from(const test_clock::time_point &tp0)
 TEST_CASE("dequeue-empty-nowait", "[mpmc_blocking_q]")
 {
     size_t q_size = 100;
-    milliseconds tolerance_wait(10);
+    milliseconds tolerance_wait(20);
     spdlog::details::mpmc_blocking_queue<int> q(q_size);
     int popped_item = 0;
 

tests/test_pattern_formatter.cpp

@@ -227,7 +227,7 @@ TEST_CASE("paddinng_truncate", "[pattern_formatter]")
     REQUIRE(log_to_str("123456", "%0!v", spdlog::pattern_time_type::local, "\n") == "\n");
 }
 
-TEST_CASE("paddinng_truncate_funcname", "[pattern_formatter]")
+TEST_CASE("padding_truncate_funcname", "[pattern_formatter]")
 {
     spdlog::sinks::test_sink_st test_sink;
 
@@ -237,13 +237,28 @@ TEST_CASE("paddinng_truncate_funcname", "[pattern_formatter]")
 
     spdlog::details::log_msg msg1{spdlog::source_loc{"ignored", 1, "func"}, "test_logger", spdlog::level::info, "message"};
     test_sink.log(msg1);
+    REQUIRE(test_sink.lines()[0] == "message [ func]");
 
     spdlog::details::log_msg msg2{spdlog::source_loc{"ignored", 1, "function"}, "test_logger", spdlog::level::info, "message"};
     test_sink.log(msg2);
+    REQUIRE(test_sink.lines()[1] == "message [funct]");
+}
 
-    auto lines = test_sink.lines();
-    REQUIRE(lines[0] == "message [ func]");
-    REQUIRE(lines[1] == "message [funct]");
+TEST_CASE("padding_funcname", "[pattern_formatter]")
+{
+    spdlog::sinks::test_sink_st test_sink;
+
+    const char *pattern = "%v [%10!]";
+    auto formatter = std::unique_ptr<spdlog::formatter>(new spdlog::pattern_formatter(pattern));
+    test_sink.set_formatter(std::move(formatter));
+
+    spdlog::details::log_msg msg1{spdlog::source_loc{"ignored", 1, "func"}, "test_logger", spdlog::level::info, "message"};
+    test_sink.log(msg1);
+    REQUIRE(test_sink.lines()[0] == "message [      func]");
+
+    spdlog::details::log_msg msg2{spdlog::source_loc{"ignored", 1, "func567890123"}, "test_logger", spdlog::level::info, "message"};
+    test_sink.log(msg2);
+    REQUIRE(test_sink.lines()[1] == "message [func567890123]");
 }
 
 TEST_CASE("clone-default-formatter", "[pattern_formatter]")

tests/test_stopwatch.cpp

@@ -0,0 +1,35 @@
+#include "includes.h"
+#include "test_sink.h"
+#include "spdlog/stopwatch.h"
+
+TEST_CASE("stopwatch1", "[stopwatch]")
+{
+    using std::chrono::milliseconds;
+    milliseconds wait_ms(250);
+    milliseconds tolerance_ms(250);
+
+    spdlog::stopwatch sw;
+    std::this_thread::sleep_for(wait_ms);
+    REQUIRE(sw.elapsed() >= wait_ms);
+    REQUIRE(sw.elapsed() <= wait_ms + tolerance_ms);
+}
+
+TEST_CASE("stopwatch2", "[stopwatch]")
+{
+    using spdlog::sinks::test_sink_st;
+
+    std::chrono::duration<double> wait_duration(0.250);
+    std::chrono::duration<double> tolerance_duration(0.250);
+
+    auto test_sink = std::make_shared<test_sink_st>();
+
+    spdlog::stopwatch sw;
+    spdlog::logger logger("test-stopwatch", test_sink);
+    logger.set_pattern("%v");
+    std::this_thread::sleep_for(wait_duration);
+    logger.info("{}", sw);
+    auto val = std::stod(test_sink->lines()[0]);
+
+    REQUIRE(val >= wait_duration.count());
+    REQUIRE(val <= (wait_duration + tolerance_duration).count());
+}