Merge pull request #531 from fogo/printf

Support for printf-style logging

.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

@@ -58,7 +58,6 @@ 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 +66,12 @@ 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/fmt/bundled/printf.cc

+/*
+ Formatting library for C++
+
+ Copyright (c) 2012 - 2016, Victor Zverovich
+ All rights reserved.
+
+ For the license information refer to format.h.
+ */
+
+#include "format.h"
+#include "printf.h"
+
+namespace fmt {
+
+template <typename Char>
+void printf(BasicWriter<Char> &w, BasicCStringRef<Char> format, ArgList args);
+
+FMT_FUNC int fprintf(std::FILE *f, CStringRef format, ArgList args) {
+  MemoryWriter w;
+  printf(w, format, args);
+  std::size_t size = w.size();
+  return std::fwrite(w.data(), 1, size, f) < size ? -1 : static_cast<int>(size);
+}
+
+#ifndef FMT_HEADER_ONLY
+
+template void PrintfFormatter<char>::format(CStringRef format);
+template void PrintfFormatter<wchar_t>::format(WCStringRef format);
+
+#endif  // FMT_HEADER_ONLY
+
+}  // namespace fmt

include/spdlog/fmt/bundled/printf.h

+/*
+ Formatting library for C++
+
+ Copyright (c) 2012 - 2016, Victor Zverovich
+ All rights reserved.
+
+ For the license information refer to format.h.
+ */
+
+#ifndef FMT_PRINTF_H_
+#define FMT_PRINTF_H_
+
+#include <algorithm>  // std::fill_n
+#include <limits>     // std::numeric_limits
+
+#include "ostream.h"
+
+namespace fmt {
+namespace internal {
+
+// Checks if a value fits in int - used to avoid warnings about comparing
+// signed and unsigned integers.
+template <bool IsSigned>
+struct IntChecker {
+  template <typename T>
+  static bool fits_in_int(T value) {
+    unsigned max = std::numeric_limits<int>::max();
+    return value <= max;
+  }
+  static bool fits_in_int(bool) { return true; }
+};
+
+template <>
+struct IntChecker<true> {
+  template <typename T>
+  static bool fits_in_int(T value) {
+    return value >= std::numeric_limits<int>::min() &&
+           value <= std::numeric_limits<int>::max();
+  }
+  static bool fits_in_int(int) { return true; }
+};
+
+class PrecisionHandler : public ArgVisitor<PrecisionHandler, int> {
+ public:
+  void report_unhandled_arg() {
+    FMT_THROW(FormatError("precision is not integer"));
+  }
+
+  template <typename T>
+  int visit_any_int(T value) {
+    if (!IntChecker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
+      FMT_THROW(FormatError("number is too big"));
+    return static_cast<int>(value);
+  }
+};
+
+// IsZeroInt::visit(arg) returns true iff arg is a zero integer.
+class IsZeroInt : public ArgVisitor<IsZeroInt, bool> {
+ public:
+  template <typename T>
+  bool visit_any_int(T value) { return value == 0; }
+};
+
+// returns the default type for format specific "%s"
+class DefaultType : public ArgVisitor<DefaultType, char> {
+ public:
+  char visit_char(int) { return 'c'; }
+
+  char visit_bool(bool) { return 's'; }
+
+  char visit_pointer(const void *) { return 'p'; }
+
+  template <typename T>
+  char visit_any_int(T) { return 'd'; }
+
+  template <typename T>
+  char visit_any_double(T) { return 'g'; }
+
+  char visit_unhandled_arg() { return 's'; }
+};
+
+template <typename T, typename U>
+struct is_same {
+  enum { value = 0 };
+};
+
+template <typename T>
+struct is_same<T, T> {
+  enum { value = 1 };
+};
+
+// An argument visitor that converts an integer argument to T for printf,
+// if T is an integral type. If T is void, the argument is converted to
+// corresponding signed or unsigned type depending on the type specifier:
+// 'd' and 'i' - signed, other - unsigned)
+template <typename T = void>
+class ArgConverter : public ArgVisitor<ArgConverter<T>, void> {
+ private:
+  internal::Arg &arg_;
+  wchar_t type_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(ArgConverter);
+
+ public:
+  ArgConverter(internal::Arg &arg, wchar_t type)
+    : arg_(arg), type_(type) {}
+
+  void visit_bool(bool value) {
+    if (type_ != 's')
+      visit_any_int(value);
+  }
+
+  void visit_char(char value) {
+    if (type_ != 's')
+      visit_any_int(value);
+  }
+
+  template <typename U>
+  void visit_any_int(U value) {
+    bool is_signed = type_ == 'd' || type_ == 'i';
+    if (type_ == 's') {
+      is_signed = std::numeric_limits<U>::is_signed;
+    }
+
+    using internal::Arg;
+    typedef typename internal::Conditional<
+        is_same<T, void>::value, U, T>::type TargetType;
+    if (sizeof(TargetType) <= sizeof(int)) {
+      // Extra casts are used to silence warnings.
+      if (is_signed) {
+        arg_.type = Arg::INT;
+        arg_.int_value = static_cast<int>(static_cast<TargetType>(value));
+      } else {
+        arg_.type = Arg::UINT;
+        typedef typename internal::MakeUnsigned<TargetType>::Type Unsigned;
+        arg_.uint_value = static_cast<unsigned>(static_cast<Unsigned>(value));
+      }
+    } else {
+      if (is_signed) {
+        arg_.type = Arg::LONG_LONG;
+        // 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_.long_long_value = static_cast<LongLong>(value);
+      } else {
+        arg_.type = Arg::ULONG_LONG;
+        arg_.ulong_long_value =
+            static_cast<typename internal::MakeUnsigned<U>::Type>(value);
+      }
+    }
+  }
+};
+
+// Converts an integer argument to char for printf.
+class CharConverter : public ArgVisitor<CharConverter, void> {
+ private:
+  internal::Arg &arg_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(CharConverter);
+
+ public:
+  explicit CharConverter(internal::Arg &arg) : arg_(arg) {}
+
+  template <typename T>
+  void visit_any_int(T value) {
+    arg_.type = internal::Arg::CHAR;
+    arg_.int_value = static_cast<char>(value);
+  }
+};
+
+// Checks if an argument is a valid printf width specifier and sets
+// left alignment if it is negative.
+class WidthHandler : public ArgVisitor<WidthHandler, unsigned> {
+ private:
+  FormatSpec &spec_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(WidthHandler);
+
+ public:
+  explicit WidthHandler(FormatSpec &spec) : spec_(spec) {}
+
+  void report_unhandled_arg() {
+    FMT_THROW(FormatError("width is not integer"));
+  }
+
+  template <typename T>
+  unsigned visit_any_int(T value) {
+    typedef typename internal::IntTraits<T>::MainType UnsignedType;
+    UnsignedType width = static_cast<UnsignedType>(value);
+    if (internal::is_negative(value)) {
+      spec_.align_ = ALIGN_LEFT;
+      width = 0 - width;
+    }
+    unsigned int_max = std::numeric_limits<int>::max();
+    if (width > int_max)
+      FMT_THROW(FormatError("number is too big"));
+    return static_cast<unsigned>(width);
+  }
+};
+}  // namespace internal
+
+/**
+  \rst
+  A ``printf`` argument formatter based on the `curiously recurring template
+  pattern <http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern>`_.
+
+  To use `~fmt::BasicPrintfArgFormatter` define a subclass that implements some
+  or all of the visit methods with the same signatures as the methods in
+  `~fmt::ArgVisitor`, for example, `~fmt::ArgVisitor::visit_int()`.
+  Pass the subclass as the *Impl* template parameter. When a formatting
+  function processes an argument, it will dispatch to a visit method
+  specific to the argument type. For example, if the argument type is
+  ``double`` then the `~fmt::ArgVisitor::visit_double()` method of a subclass
+  will be called. If the subclass doesn't contain a method with this signature,
+  then a corresponding method of `~fmt::BasicPrintfArgFormatter` or its
+  superclass will be called.
+  \endrst
+ */
+template <typename Impl, typename Char, typename Spec>
+class BasicPrintfArgFormatter :
+    public internal::ArgFormatterBase<Impl, Char, Spec> {
+ private:
+  void write_null_pointer() {
+    this->spec().type_ = 0;
+    this->write("(nil)");
+  }
+
+  typedef internal::ArgFormatterBase<Impl, Char, Spec> Base;
+
+ public:
+  /**
+    \rst
+    Constructs an argument formatter object.
+    *writer* is a reference to the output writer and *spec* contains format
+    specifier information for standard argument types.
+    \endrst
+   */
+  BasicPrintfArgFormatter(BasicWriter<Char> &w, Spec &s)
+  : internal::ArgFormatterBase<Impl, Char, Spec>(w, s) {}
+
+  /** Formats an argument of type ``bool``. */
+  void visit_bool(bool value) {
+    Spec &fmt_spec = this->spec();
+    if (fmt_spec.type_ != 's')
+      return this->visit_any_int(value);
+    fmt_spec.type_ = 0;
+    this->write(value);
+  }
+
+  /** Formats a character. */
+  void visit_char(int value) {
+    const Spec &fmt_spec = this->spec();
+    BasicWriter<Char> &w = this->writer();
+    if (fmt_spec.type_ && fmt_spec.type_ != 'c')
+      w.write_int(value, fmt_spec);
+    typedef typename BasicWriter<Char>::CharPtr CharPtr;
+    CharPtr out = CharPtr();
+    if (fmt_spec.width_ > 1) {
+      Char fill = ' ';
+      out = w.grow_buffer(fmt_spec.width_);
+      if (fmt_spec.align_ != ALIGN_LEFT) {
+        std::fill_n(out, fmt_spec.width_ - 1, fill);
+        out += fmt_spec.width_ - 1;
+      } else {
+        std::fill_n(out + 1, fmt_spec.width_ - 1, fill);
+      }
+    } else {
+      out = w.grow_buffer(1);
+    }
+    *out = static_cast<Char>(value);
+  }
+
+  /** Formats a null-terminated C string. */
+  void visit_cstring(const char *value) {
+    if (value)
+      Base::visit_cstring(value);
+    else if (this->spec().type_ == 'p')
+      write_null_pointer();
+    else
+      this->write("(null)");
+  }
+
+  /** Formats a pointer. */
+  void visit_pointer(const void *value) {
+    if (value)
+      return Base::visit_pointer(value);
+    this->spec().type_ = 0;
+    write_null_pointer();
+  }
+
+  /** Formats an argument of a custom (user-defined) type. */
+  void visit_custom(internal::Arg::CustomValue c) {
+    BasicFormatter<Char> formatter(ArgList(), this->writer());
+    const Char format_str[] = {'}', 0};
+    const Char *format = format_str;
+    c.format(&formatter, c.value, &format);
+  }
+};
+
+/** The default printf argument formatter. */
+template <typename Char>
+class PrintfArgFormatter :
+    public BasicPrintfArgFormatter<PrintfArgFormatter<Char>, Char, FormatSpec> {
+ public:
+  /** Constructs an argument formatter object. */
+  PrintfArgFormatter(BasicWriter<Char> &w, FormatSpec &s)
+  : BasicPrintfArgFormatter<PrintfArgFormatter<Char>, Char, FormatSpec>(w, s) {}
+};
+
+/** This template formats data and writes the output to a writer. */
+template <typename Char, typename ArgFormatter = PrintfArgFormatter<Char> >
+class PrintfFormatter : private internal::FormatterBase {
+ private:
+  BasicWriter<Char> &writer_;
+
+  void parse_flags(FormatSpec &spec, const Char *&s);
+
+  // Returns the argument with specified index or, if arg_index is equal
+  // to the maximum unsigned value, the next argument.
+  internal::Arg get_arg(
+      const Char *s,
+      unsigned arg_index = (std::numeric_limits<unsigned>::max)());
+
+  // Parses argument index, flags and width and returns the argument index.
+  unsigned parse_header(const Char *&s, FormatSpec &spec);
+
+ public:
+  /**
+   \rst
+   Constructs a ``PrintfFormatter`` object. References to the arguments and
+   the writer are stored in the formatter object so make sure they have
+   appropriate lifetimes.
+   \endrst
+   */
+  explicit PrintfFormatter(const ArgList &al, BasicWriter<Char> &w)
+    : FormatterBase(al), writer_(w) {}
+
+  /** Formats stored arguments and writes the output to the writer. */
+  void format(BasicCStringRef<Char> format_str);
+};
+
+template <typename Char, typename AF>
+void PrintfFormatter<Char, AF>::parse_flags(FormatSpec &spec, const Char *&s) {
+  for (;;) {
+    switch (*s++) {
+      case '-':
+        spec.align_ = ALIGN_LEFT;
+        break;
+      case '+':
+        spec.flags_ |= SIGN_FLAG | PLUS_FLAG;
+        break;
+      case '0':
+        spec.fill_ = '0';
+        break;
+      case ' ':
+        spec.flags_ |= SIGN_FLAG;
+        break;
+      case '#':
+        spec.flags_ |= HASH_FLAG;
+        break;
+      default:
+        --s;
+        return;
+    }
+  }
+}
+
+template <typename Char, typename AF>
+internal::Arg PrintfFormatter<Char, AF>::get_arg(const Char *s,
+                                                 unsigned arg_index) {
+  (void)s;
+  const char *error = FMT_NULL;
+  internal::Arg arg = arg_index == std::numeric_limits<unsigned>::max() ?
+    next_arg(error) : FormatterBase::get_arg(arg_index - 1, error);
+  if (error)
+    FMT_THROW(FormatError(!*s ? "invalid format string" : error));
+  return arg;
+}
+
+template <typename Char, typename AF>
+unsigned PrintfFormatter<Char, AF>::parse_header(
+  const Char *&s, FormatSpec &spec) {
+  unsigned arg_index = std::numeric_limits<unsigned>::max();
+  Char c = *s;
+  if (c >= '0' && c <= '9') {
+    // Parse an argument index (if followed by '$') or a width possibly
+    // preceded with '0' flag(s).
+    unsigned value = internal::parse_nonnegative_int(s);
+    if (*s == '$') {  // value is an argument index
+      ++s;
+      arg_index = value;
+    } else {
+      if (c == '0')
+        spec.fill_ = '0';
+      if (value != 0) {
+        // Nonzero value means that we parsed width and don't need to
+        // parse it or flags again, so return now.
+        spec.width_ = value;
+        return arg_index;
+      }
+    }
+  }
+  parse_flags(spec, s);
+  // Parse width.
+  if (*s >= '0' && *s <= '9') {
+    spec.width_ = internal::parse_nonnegative_int(s);
+  } else if (*s == '*') {
+    ++s;
+    spec.width_ = internal::WidthHandler(spec).visit(get_arg(s));
+  }
+  return arg_index;
+}
+
+template <typename Char, typename AF>
+void PrintfFormatter<Char, AF>::format(BasicCStringRef<Char> format_str) {
+  const Char *start = format_str.c_str();
+  const Char *s = start;
+  while (*s) {
+    Char c = *s++;
+    if (c != '%') continue;
+    if (*s == c) {
+      write(writer_, start, s);
+      start = ++s;
+      continue;
+    }
+    write(writer_, start, s - 1);
+
+    FormatSpec spec;
+    spec.align_ = ALIGN_RIGHT;
+
+    // Parse argument index, flags and width.
+    unsigned arg_index = parse_header(s, spec);
+
+    // Parse precision.
+    if (*s == '.') {
+      ++s;
+      if ('0' <= *s && *s <= '9') {
+        spec.precision_ = static_cast<int>(internal::parse_nonnegative_int(s));
+      } else if (*s == '*') {
+        ++s;
+        spec.precision_ = internal::PrecisionHandler().visit(get_arg(s));
+      } else {
+        spec.precision_ = 0;
+      }
+    }
+
+    using internal::Arg;
+    Arg arg = get_arg(s, arg_index);
+    if (spec.flag(HASH_FLAG) && internal::IsZeroInt().visit(arg))
+      spec.flags_ &= ~internal::to_unsigned<int>(HASH_FLAG);
+    if (spec.fill_ == '0') {
+      if (arg.type <= Arg::LAST_NUMERIC_TYPE)
+        spec.align_ = ALIGN_NUMERIC;
+      else
+        spec.fill_ = ' ';  // Ignore '0' flag for non-numeric types.
+    }
+
+    // Parse length and convert the argument to the required type.
+    using internal::ArgConverter;
+    switch (*s++) {
+    case 'h':
+      if (*s == 'h')
+        ArgConverter<signed char>(arg, *++s).visit(arg);
+      else
+        ArgConverter<short>(arg, *s).visit(arg);
+      break;
+    case 'l':
+      if (*s == 'l')
+        ArgConverter<fmt::LongLong>(arg, *++s).visit(arg);
+      else
+        ArgConverter<long>(arg, *s).visit(arg);
+      break;
+    case 'j':
+      ArgConverter<intmax_t>(arg, *s).visit(arg);
+      break;
+    case 'z':
+      ArgConverter<std::size_t>(arg, *s).visit(arg);
+      break;
+    case 't':
+      ArgConverter<std::ptrdiff_t>(arg, *s).visit(arg);
+      break;
+    case 'L':
+      // printf produces garbage when 'L' is omitted for long double, no
+      // need to do the same.
+      break;
+    default:
+      --s;
+      ArgConverter<void>(arg, *s).visit(arg);
+    }
+
+    // Parse type.
+    if (!*s)
+      FMT_THROW(FormatError("invalid format string"));
+    spec.type_ = static_cast<char>(*s++);
+
+    if (spec.type_ == 's') {
+      // set the format type to the default if 's' is specified
+      spec.type_ = internal::DefaultType().visit(arg);
+    }
+
+    if (arg.type <= Arg::LAST_INTEGER_TYPE) {
+      // Normalize type.
+      switch (spec.type_) {
+      case 'i': case 'u':
+        spec.type_ = 'd';
+        break;
+      case 'c':
+        // TODO: handle wchar_t
+        internal::CharConverter(arg).visit(arg);
+        break;
+      }
+    }
+
+    start = s;
+
+    // Format argument.
+    AF(writer_, spec).visit(arg);
+  }
+  write(writer_, start, s);
+}
+
+inline void printf(Writer &w, CStringRef format, ArgList args) {
+  PrintfFormatter<char>(args, w).format(format);
+}
+FMT_VARIADIC(void, printf, Writer &, CStringRef)
+
+inline void printf(WWriter &w, WCStringRef format, ArgList args) {
+  PrintfFormatter<wchar_t>(args, w).format(format);
+}
+FMT_VARIADIC(void, printf, WWriter &, WCStringRef)
+
+/**
+  \rst
+  Formats arguments and returns the result as a string.
+
+  **Example**::
+
+    std::string message = fmt::sprintf("The answer is %d", 42);
+  \endrst
+*/
+inline std::string sprintf(CStringRef format, ArgList args) {
+  MemoryWriter w;
+  printf(w, format, args);
+  return w.str();
+}
+FMT_VARIADIC(std::string, sprintf, CStringRef)
+
+inline std::wstring sprintf(WCStringRef format, ArgList args) {
+  WMemoryWriter w;
+  printf(w, format, args);
+  return w.str();
+}
+FMT_VARIADIC_W(std::wstring, sprintf, WCStringRef)
+
+/**
+  \rst
+  Prints formatted data to the file *f*.
+
+  **Example**::
+
+    fmt::fprintf(stderr, "Don't %s!", "panic");
+  \endrst
+ */
+FMT_API int fprintf(std::FILE *f, CStringRef format, ArgList args);
+FMT_VARIADIC(int, fprintf, std::FILE *, CStringRef)
+
+/**
+  \rst
+  Prints formatted data to ``stdout``.
+
+  **Example**::
+
+    fmt::printf("Elapsed time: %.2f seconds", 1.23);
+  \endrst
+ */
+inline int printf(CStringRef format, ArgList args) {
+  return fprintf(stdout, format, args);
+}
+FMT_VARIADIC(int, printf, CStringRef)
+
+/**
+  \rst
+  Prints formatted data to the stream *os*.
+
+  **Example**::
+
+    fprintf(cerr, "Don't %s!", "panic");
+  \endrst
+ */
+inline int fprintf(std::ostream &os, CStringRef format_str, ArgList args) {
+  MemoryWriter w;
+  printf(w, format_str, args);
+  internal::write(os, w);
+  return static_cast<int>(w.size());
+}
+FMT_VARIADIC(int, fprintf, std::ostream &, CStringRef)
+}  // namespace fmt
+
+#ifdef FMT_HEADER_ONLY
+# include "printf.cc"
+#endif
+
+#endif  // FMT_PRINTF_H_

include/spdlog/fmt/fmt.h

@@ -19,10 +19,16 @@
 #define FMT_USE_WINDOWS_H 0
 #endif
 #include "spdlog/fmt/bundled/format.h"
+#if defined(SPDLOG_FMT_PRINTF)
+#include "spdlog/fmt/bundled/printf.h"
+#endif
 
 #else //external fmtlib
 
 #include <fmt/format.h>
+#if defined(SPDLOG_FMT_PRINTF)
+#include <fmt/printf.h>
+#endif
 
 #endif
 

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();