Fixed whitespace, added %e/%g to README.md

2 files changed, 44 insertions, 41 deletions

diff --git a/README.md b/README.md
index 0b39488..f86b7e4 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,7 @@ Therefore I decided to write an own, final implementation which meets the follow
  - Support of decimal/floating number representation (with an own fast itoa/ftoa)

  - Reentrant and thread-safe, malloc free, no static vars/buffers

  - LINT and compiler L4 warning free, mature, coverity clean, automotive ready

- - Extensive test suite (> 370 test cases) passing

+ - Extensive test suite (> 390 test cases) passing

  - Simply the best *printf* around the net

  - MIT license

 

@@ -92,6 +92,8 @@ The following format specifiers are supported:
 | x      | Unsigned hexadecimal integer (lowercase) |

 | X      | Unsigned hexadecimal integer (uppercase) |

 | f or F | Decimal floating point |

+| e or E | Scientific-notation (exponential) floating point |

+| g or G | Scientific or decimal floating point |

 | c      | Single character |

 | s      | String of characters |

 | p      | Pointer address |

@@ -164,6 +166,7 @@ int length = sprintf(NULL, "Hello, world"); // length is set to 12
 | PRINTF_NTOA_BUFFER_SIZE          | 32        | ntoa (integer) conversion buffer size. This must be big enough to hold one converted numeric number _including_ leading zeros, normally 32 is a sufficient value. Created on the stack |

 | PRINTF_FTOA_BUFFER_SIZE          | 32        | ftoa (float) conversion buffer size. This must be big enough to hold one converted float number _including_ leading zeros, normally 32 is a sufficient value. Created on the stack |

 | PRINTF_DISABLE_SUPPORT_FLOAT     | undefined | Define this to disable floating point (%f) support |

+| PRINTF_DISABLE_SUPPORT_EXPONENTIAL | undefined | Define this to disable exponential floating point (%e) support |

 | PRINTF_DISABLE_SUPPORT_LONG_LONG | undefined | Define this to disable long long (%ll) support |

 | PRINTF_DISABLE_SUPPORT_PTRDIFF_T | undefined | Define this to disable ptrdiff_t (%t) support |

 

diff --git a/printf.c b/printf.c
index 62cc52c..99eb7c6 100644
--- a/printf.c
+++ b/printf.c
@@ -106,7 +106,7 @@
 #define FLAGS_LONG      (1U <<  8U)

 #define FLAGS_LONG_LONG (1U <<  9U)

 #define FLAGS_PRECISION (1U << 10U)

-#define FLAGS_ADAPT_EXP	(1U << 11U)

+#define FLAGS_ADAPT_EXP (1U << 11U)

 

 

 // output function type

@@ -337,7 +337,7 @@ static size_t _ftoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
   if (value < -DBL_MAX)

     return _out_rev(out, buffer, idx, maxlen, "fni-", 4, width, flags);

   if (value > DBL_MAX)

-	return _out_rev(out, buffer, idx, maxlen, (flags & FLAGS_PLUS) ? "fni+" : "fni", (flags & FLAGS_PLUS) ? 4 : 3, width, flags);

+    return _out_rev(out, buffer, idx, maxlen, (flags & FLAGS_PLUS) ? "fni+" : "fni", (flags & FLAGS_PLUS) ? 4 : 3, width, flags);

 

   // test for very large values

   // standard printf behavior is to print EVERY whole number digit -- which could be 100s of characters overflowing your buffers == bad

@@ -456,14 +456,14 @@ static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
 {

   // check for special values

   if ((value != value)||(value > DBL_MAX)||(value < -DBL_MAX))

-	return _ftoa(out, buffer, idx, maxlen, value, prec, width, flags);

+    return _ftoa(out, buffer, idx, maxlen, value, prec, width, flags);

   

   // determine the sign

   bool negative = value < 0;

   if (negative) value = -value;

 

   // determine the decimal exponent

-  int expval = (int)floor(log10(value));	// "value" must be +ve

+  int expval = (int)floor(log10(value));    // "value" must be +ve

 

   // the exponent format is "%+03d" and largest value is "307", so set aside 4-5 characters

   unsigned int minwidth = ((expval < 100)&&(expval > -100)) ? 4 : 5;

@@ -475,23 +475,23 @@ static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
   

   // in "%g" mode, "prec" is the number of *significant figures* not decimals

   if (flags & FLAGS_ADAPT_EXP) {

-	// do we want to fall-back to "%f" mode for small number?

-	if ((expval > -5)&&(expval < 6)) {

-	  if ((int)prec > expval) {

-		prec = (unsigned)((int)prec - expval - 1);

+    // do we want to fall-back to "%f" mode for small number?

+    if ((expval > -5)&&(expval < 6)) {

+      if ((int)prec > expval) {

+        prec = (unsigned)((int)prec - expval - 1);

       } else {

-		prec = 0;

-	  }

-	  // TODO: there's also a special case where we're supposed to ELIMINATE digits from the whole part

-	  flags |= FLAGS_PRECISION; // make sure _ftoa respects precision

-	  

-	  // no characters in exponent

-	  minwidth = 0;

-	  expval = 0;

-	} else {

-	  // we use one sigfig for the whole part

-	  if ((prec > 0)&&(flags & FLAGS_PRECISION)) --prec;

-	}

+        prec = 0;

+      }

+      // TODO: there's also a special case where we're supposed to ELIMINATE digits from the whole part

+      flags |= FLAGS_PRECISION; // make sure _ftoa respects precision

+      

+      // no characters in exponent

+      minwidth = 0;

+      expval = 0;

+    } else {

+      // we use one sigfig for the whole part

+      if ((prec > 0)&&(flags & FLAGS_PRECISION)) --prec;

+    }

   }

   // will everything fit?

   unsigned int fwidth = width;

@@ -499,12 +499,12 @@ static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
     // we didn't fall-back so subtract the characters required for the exponent

     fwidth -= minwidth;

   } else {

-	// not enough characters, so go back to default sizing

-	fwidth = 0;

+    // not enough characters, so go back to default sizing

+    fwidth = 0;

   }

   if ((flags & FLAGS_LEFT) && minwidth) {

-	// if we're padding on the right, DON'T pad the floating part

-	fwidth = 0;

+    // if we're padding on the right, DON'T pad the floating part

+    fwidth = 0;

   }

 

   // rescale the float value

@@ -516,14 +516,14 @@ static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, d
 

   // output the exponent part

   if (minwidth) {

-	// output the exponential symbol

-	out((flags & FLAGS_UPPERCASE) ? 'E' : 'e', buffer, idx++, maxlen);

-	// output the exponent value

-	idx = _ntoa_long(out, buffer, idx, maxlen, (expval < 0) ? -expval : expval, expval < 0, 10, 0, minwidth-1, FLAGS_ZEROPAD | FLAGS_PLUS);

-	// might need to right-pad spaces

-	if (flags & FLAGS_LEFT) {

-		while (idx - start_idx < width) out(' ', buffer, idx++, maxlen);

-	}

+    // output the exponential symbol

+    out((flags & FLAGS_UPPERCASE) ? 'E' : 'e', buffer, idx++, maxlen);

+    // output the exponent value

+    idx = _ntoa_long(out, buffer, idx, maxlen, (expval < 0) ? -expval : expval, expval < 0, 10, 0, minwidth-1, FLAGS_ZEROPAD | FLAGS_PLUS);

+    // might need to right-pad spaces

+    if (flags & FLAGS_LEFT) {

+      while (idx - start_idx < width) out(' ', buffer, idx++, maxlen);

+    }

   }

   return idx;

 }

@@ -716,20 +716,20 @@ static int _vsnprintf(out_fct_type out, char* buffer, const size_t maxlen, const
 #if defined(PRINTF_SUPPORT_FLOAT)

       case 'f' :

       case 'F' :

-	    if (*format == 'F') flags |= FLAGS_UPPERCASE;

+        if (*format == 'F') flags |= FLAGS_UPPERCASE;

         idx = _ftoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags);

         format++;

         break;

 #if defined(PRINTF_SUPPORT_EXPONENTIAL)

       case 'e':

-	  case 'E':

+      case 'E':

       case 'g':

-	  case 'G':

-	    if ((*format == 'g')||(*format == 'G')) flags |= FLAGS_ADAPT_EXP;

-		if ((*format == 'E')||(*format == 'G')) flags |= FLAGS_UPPERCASE;

-	    idx = _etoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags);

-		format++;

-		break;

+      case 'G':

+        if ((*format == 'g')||(*format == 'G')) flags |= FLAGS_ADAPT_EXP;

+        if ((*format == 'E')||(*format == 'G')) flags |= FLAGS_UPPERCASE;

+        idx = _etoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags);

+        format++;

+        break;

 #endif  // PRINTF_SUPPORT_EXPONENTIAL

 #endif  // PRINTF_SUPPORT_FLOAT

       case 'c' : {