allow printf style logging

* tests updated for printf style
* tests makefile support printf style

.travis.yml

@@ -85,6 +85,7 @@ script:
   - ./"${BIN}"
   - valgrind --trace-children=yes --leak-check=full ./"${BIN}"
   - cd $CHECKOUT_PATH/tests; make rebuild; ./tests
+  - cd $CHECKOUT_PATH/tests; STYLE=printf make rebuild; ./tests
 
 notifications:
   email: false

include/spdlog/details/logger_impl.h

@@ -8,6 +8,14 @@
 #include "spdlog/logger.h"
 #include "spdlog/sinks/stdout_sinks.h"
 
+#if defined(SPDLOG_FMT_PRINTF)
+#if !defined(SPDLOG_FMT_EXTERNAL)
+#include "spdlog/fmt/bundled/printf.h"
+#else //external fmtlib
+#include <fmt/printf.h>
+#endif
+#endif
+
 #include <memory>
 #include <string>
 
@@ -58,7 +66,6 @@ inline void spdlog::logger::set_pattern(const std::string& pattern, pattern_time
     _set_pattern(pattern, pattern_time);
 }
 
-
 template <typename... Args>
 inline void spdlog::logger::log(level::level_enum lvl, const char* fmt, const Args&... args)
 {
@@ -67,7 +74,12 @@ inline void spdlog::logger::log(level::level_enum lvl, const char* fmt, const Ar
     try
     {
         details::log_msg log_msg(&_name, lvl);
+
+#if defined(SPDLOG_FMT_PRINTF)
+        fmt::printf(log_msg.raw, fmt, args...);
+#else
         log_msg.raw.write(fmt, args...);
+#endif
         _sink_it(log_msg);
     }
     catch (const std::exception &ex)

include/spdlog/tweakme.h

@@ -96,6 +96,14 @@
 ///////////////////////////////////////////////////////////////////////////////
 
 
+///////////////////////////////////////////////////////////////////////////////
+// Uncomment to use printf-style messages in your logs instead of the usual
+// format-style used by default.
+//
+// #define SPDLOG_FMT_PRINTF
+///////////////////////////////////////////////////////////////////////////////
+
+
 ///////////////////////////////////////////////////////////////////////////////
 // Uncomment to enable syslog (disabled by default)
 //

tests/Makefile

 CXX	?= g++
-CXXFLAGS	=  -Wall  -pedantic -std=c++11 -pthread -O2 -I../include
+ifeq ($(STYLE),printf)
+    $(info *** PRINTF STYLE ***)
+    CXXFLAGS	=  -DSPDLOG_FMT_PRINTF -Wall  -pedantic -std=c++11 -pthread -O2 -I../include
+else
+    $(info *** FORMAT STYLE ***)
+    CXXFLAGS	=  -Wall  -pedantic -std=c++11 -pthread -O2 -I../include
+endif
 LDPFALGS = -pthread
 
 CPP_FILES := $(wildcard *.cpp)

tests/cond_logging.cpp

@@ -135,6 +135,7 @@ TEST_CASE("conditional_trace_varargs", "[conditional_trace_varargs]")
     //const char
     for (auto i = 0; i < 2; i++)
     {
+#if !defined(SPDLOG_FMT_PRINTF)
         REQUIRE(conditional_log_varags(spdlog::level::trace, (i % 2 == 0), "Hello {}", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
         REQUIRE(conditional_log_varags(spdlog::level::debug, (i % 2 == 0), "Hello {}", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
         REQUIRE(conditional_log_varags(spdlog::level::info, (i % 2 == 0), "Hello {}", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
@@ -150,5 +151,24 @@ TEST_CASE("conditional_trace_varargs", "[conditional_trace_varargs]")
         REQUIRE(conditional_log_varags(spdlog::level::err, (i % 2 == 0), L"Hello {}", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
         REQUIRE(conditional_log_varags(spdlog::level::critical, (i % 2 == 0), L"Hello {}", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
 #endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
+#else
+        REQUIRE(conditional_log_varags(spdlog::level::trace, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+        REQUIRE(conditional_log_varags(spdlog::level::debug, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+        REQUIRE(conditional_log_varags(spdlog::level::info, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+        REQUIRE(conditional_log_varags(spdlog::level::warn, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+        REQUIRE(conditional_log_varags(spdlog::level::err, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+        REQUIRE(conditional_log_varags(spdlog::level::critical, (i % 2 == 0), "Hello %d", i) == (i % 2 == 0 ? "Hello " + std::to_string(i) : ""));
+
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+        REQUIRE(conditional_log_varags(spdlog::level::trace, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+        REQUIRE(conditional_log_varags(spdlog::level::debug, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+        REQUIRE(conditional_log_varags(spdlog::level::info, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+        REQUIRE(conditional_log_varags(spdlog::level::warn, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+        REQUIRE(conditional_log_varags(spdlog::level::err, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+        REQUIRE(conditional_log_varags(spdlog::level::critical, (i % 2 == 0), L"Hello %d", i) == (i % 2 == 0 ? L"Hello " + std::to_wstring(i) : L""));
+#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
+#endif // !defined(SPDLOG_FMT_PRINTF)
     }
 }
\ No newline at end of file

tests/errors.cpp

@@ -26,8 +26,13 @@ TEST_CASE("default_error_handler", "[errors]]")
 
     auto logger = spdlog::create<spdlog::sinks::simple_file_sink_mt>("logger", filename, true);
     logger->set_pattern("%v");
+#if !defined(SPDLOG_FMT_PRINTF)
     logger->info("Test message {} {}", 1);
     logger->info("Test message {}", 2);
+#else
+    logger->info("Test message %d %d", 1);
+    logger->info("Test message %d", 2);
+#endif
     logger->flush();
 
     REQUIRE(file_contents(filename) == std::string("Test message 2\n"));
@@ -50,7 +55,11 @@ TEST_CASE("custom_error_handler", "[errors]]")
         throw custom_ex();
     });
     logger->info("Good message #1");
+#if !defined(SPDLOG_FMT_PRINTF)
     REQUIRE_THROWS_AS(logger->info("Bad format msg {} {}", "xxx"), custom_ex);
+#else
+    REQUIRE_THROWS_AS(logger->info("Bad format msg %s %s", "xxx"), custom_ex);
+#endif
     logger->info("Good message #2");
     REQUIRE(count_lines(filename) == 2);
 }
@@ -81,7 +90,11 @@ TEST_CASE("async_error_handler", "[errors]]")
             ofs << err_msg;
         });
         logger->info("Good message #1");
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Bad format msg {} {}", "xxx");
+#else
+        logger->info("Bad format msg %s %s", "xxx");
+#endif
         logger->info("Good message #2");
         spdlog::drop("logger"); //force logger to drain the queue and shutdown
         spdlog::set_sync_mode();

tests/file_log.cpp

@@ -12,9 +12,13 @@ TEST_CASE("simple_file_logger", "[simple_logger]]")
     auto logger = spdlog::create<spdlog::sinks::simple_file_sink_mt>("logger", filename);
     logger->set_pattern("%v");
 
-
+#if !defined(SPDLOG_FMT_PRINTF)
     logger->info("Test message {}", 1);
     logger->info("Test message {}", 2);
+#else
+    logger->info("Test message %d", 1);
+    logger->info("Test message %d", 2);
+#endif
     logger->flush();
     REQUIRE(file_contents(filename) == std::string("Test message 1\nTest message 2\n"));
     REQUIRE(count_lines(filename) == 2);
@@ -33,8 +37,13 @@ TEST_CASE("flush_on", "[flush_on]]")
     logger->trace("Should not be flushed");
     REQUIRE(count_lines(filename) == 0);
 
+#if !defined(SPDLOG_FMT_PRINTF)
     logger->info("Test message {}", 1);
     logger->info("Test message {}", 2);
+#else
+    logger->info("Test message %d", 1);
+    logger->info("Test message %d", 2);
+#endif
     logger->flush();
     REQUIRE(file_contents(filename) == std::string("Should not be flushed\nTest message 1\nTest message 2\n"));
     REQUIRE(count_lines(filename) == 3);
@@ -47,7 +56,13 @@ TEST_CASE("rotating_file_logger1", "[rotating_logger]]")
     auto logger = spdlog::rotating_logger_mt("logger", basename, 1024, 0);
 
     for (int i = 0; i < 10; ++i)
+    {
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Test message {}", i);
+#else
+        logger->info("Test message %d", i);
+#endif
+    }
 
     logger->flush();
     auto filename = basename;
@@ -67,7 +82,13 @@ TEST_CASE("rotating_file_logger2", "[rotating_logger]]")
     auto filename = basename;
     REQUIRE(count_lines(filename) == 10);
     for (int i = 0; i < 1000; i++)
+    {
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Test message {}", i);
+#else
+        logger->info("Test message %d", i);
+#endif
+    }
 
     logger->flush();
     REQUIRE(get_filesize(filename) <= 1024);
@@ -88,7 +109,13 @@ TEST_CASE("daily_logger", "[daily_logger]]")
     auto logger = spdlog::daily_logger_mt("logger", basename, 0, 0);
     logger->flush_on(spdlog::level::info);
     for (int i = 0; i < 10; ++i)
+    {
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Test message {}", i);
+#else
+        logger->info("Test message %d", i);
+#endif
+    }
 
     auto filename = w.str();
     REQUIRE(count_lines(filename) == 10);
@@ -110,7 +137,13 @@ TEST_CASE("daily_logger with dateonly calculator", "[daily_logger_dateonly]]")
 
     auto logger = spdlog::create<sink_type>("logger", basename, 0, 0);
     for (int i = 0; i < 10; ++i)
+    {
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Test message {}", i);
+#else
+        logger->info("Test message %d", i);
+#endif
+    }
     logger->flush();
     auto filename = w.str();
     REQUIRE(count_lines(filename) == 10);
@@ -142,7 +175,13 @@ TEST_CASE("daily_logger with custom calculator", "[daily_logger_custom]]")
 
     auto logger = spdlog::create<sink_type>("logger", basename, 0, 0);
     for (int i = 0; i < 10; ++i)
+    {
+#if !defined(SPDLOG_FMT_PRINTF)
         logger->info("Test message {}", i);
+#else
+        logger->info("Test message %d", i);
+#endif
+    }
 
     logger->flush();
     auto filename = w.str();