From 0161971c17102a24e529461fd49e9b12e9599835 Mon Sep 17 00:00:00 2001
From: hybrid <hybrid@dfc29bdd-3216-0410-991c-e03cc46cb475>
Date: Wed, 27 Apr 2011 22:15:51 +0000
Subject: [PATCH] Add some more features from assimp patch. Also fix some
 things in the previously added methods.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@3673 dfc29bdd-3216-0410-991c-e03cc46cb475
---
 include/fast_atof.h | 117 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 103 insertions(+), 14 deletions(-)

diff --git a/include/fast_atof.h b/include/fast_atof.h
index ed423903..79e560d2 100644
--- a/include/fast_atof.h
+++ b/include/fast_atof.h
@@ -111,6 +111,24 @@ inline s32 strtol10(const char* in, const char** out=0)
 	}
 }
 
+//! Convert a hex-encoded character to an unsigned integer.
+/** \param[in] in The digit to convert. Only digits 0 to 9 and chars A-F,a-f
+    will be considered.
+    \return The unsigned integer value of the digit. 0xffffffff if the input is
+    not hex
+*/
+inline u32 ctoul16(char in)
+{
+	if (in >= '0' && in <= '9')
+		return in - '0';
+	else if (in >= 'a' && in <= 'f')
+		return 10u + in - 'a';
+	else if (in >= 'A' && in <= 'F')
+		return 10u + in - 'A';
+	else
+		return 0xffffffff;
+}
+
 //! Convert a simple string of base 16 digits into an unsigned 32 bit integer.
 /** \param[in] in: The string of digits to convert. No leading chars are
     allowed, only digits 0 to 9 and chars A-F,a-f are allowed. Parsing stops
@@ -120,7 +138,7 @@ inline s32 strtol10(const char* in, const char** out=0)
     \return The unsigned integer value of the digits. If the string specifies
     too many digits to encode in an u32 then INT_MAX will be returned.
 */
-inline s32 strtoul16(const char* in, const char** out=0)
+inline u32 strtoul16(const char* in, const char** out=0)
 {
 	if (!in)
 	{
@@ -145,7 +163,7 @@ inline s32 strtoul16(const char* in, const char** out=0)
 		if (tmp<unsignedValue)
 		{
 			unsignedValue=(u32)INT_MAX;
-			overflow=false;
+			overflow=true;
 		}
 		if (!overflow)
 			unsignedValue = tmp;
@@ -158,8 +176,73 @@ inline s32 strtoul16(const char* in, const char** out=0)
 	return unsignedValue;
 }
 
+//! Convert a simple string of base 8 digits into an unsigned 32 bit integer.
+/** \param[in] in The string of digits to convert. No leading chars are
+    allowed, only digits 0 to 7 are allowed. Parsing stops at the first illegal
+    char.
+    \param[out] out (optional) If provided, it will be set to point at the
+    first character not used in the calculation.
+    \return The unsigned integer value of the digits. If the string specifies
+    too many digits to encode in an u32 then INT_MAX will be returned.
+*/
+inline u32 strtoul8(const char* in, const char** out=0)
+{
+	if (!in)
+	{
+		if (out)
+			*out = in;
+		return 0;
+	}
+
+	bool overflow=false;
+	u32 unsignedValue = 0;
+	while (true)
+	{
+		u32 tmp = 0;
+		if ((*in >= '0') && (*in <= '7'))
+			tmp = (unsignedValue << 3u) + (*in - '0');
+		else
+			break;
+		if (tmp<unsignedValue)
+		{
+			unsignedValue=(u32)INT_MAX;
+			overflow=true;
+		}
+		if (!overflow)
+			unsignedValue = tmp;
+		++in;
+	}
+
+	if (out)
+		*out = in;
+
+	return unsignedValue;
+}
+
+//! Convert a C-style prefixed string (hex, oct, integer) into an unsigned 32 bit integer.
+/** \param[in] in The string of digits to convert. If string starts with 0x the
+    hex parser is used, if only leading 0 is used, oct parser is used. In all
+    other cases, the usual unsigned parser is used.
+    \param[out] out (optional) If provided, it will be set to point at the
+    first character not used in the calculation.
+    \return The unsigned integer value of the digits. If the string specifies
+    too many digits to encode in an u32 then INT_MAX will be returned.
+*/
+inline u32 strtoul_prefix(const char* in, const char** out=0)
+{
+	if (!in)
+	{
+		if (out)
+			*out = in;
+		return 0;
+	}
+	if ('0'==in[0])
+		return ('x'==in[1] ? strtoul16(in+2,out) : strtoul8(in+1,out));
+	return strtoul10(in,out);
+}
+
 //! Converts a sequence of digits into a whole positive floating point value.
-/** Only digits 0 to 9 are parsed.  Parsing stops at any other character, 
+/** Only digits 0 to 9 are parsed.  Parsing stops at any other character,
     including sign characters or a decimal point.
     \param in: the sequence of digits to convert.
     \param out: (optional) will be set to point at the first non-converted
@@ -194,7 +277,7 @@ inline f32 strtof10(const char* in, const char** out = 0)
 
 	f32 floatValue = (f32)intValue;
 
-	// If there are any digits left to parse, then we need to use 
+	// If there are any digits left to parse, then we need to use
 	// floating point arithmetic from here.
 	while ( ( *in >= '0') && ( *in <= '9' ) )
 	{
@@ -211,14 +294,14 @@ inline f32 strtof10(const char* in, const char** out = 0)
 }
 
 //! Provides a fast function for converting a string into a float.
-/** This is not guaranteed to be as accurate as atof(), but is 
+/** This is not guaranteed to be as accurate as atof(), but is
     approximately 6 to 8 times as fast.
-    \param[in] in: The string to convert. 
-    \param[out] out: The resultant float will be written here.
-    \return A pointer to the first character in the string that wasn't
-    used to create the float value.
+    \param[in] in The string to convert.
+    \param[out] result The resultant float will be written here.
+    \return Pointer to the first character in the string that wasn't used
+    to create the float value.
 */
-inline const char* fast_atof_move(const char * in, f32& result)
+inline const char* fast_atof_move(const char* in, f32& result)
 {
 	// Please run this regression test when making any modifications to this function:
 	// https://sourceforge.net/tracker/download.php?group_id=74339&atid=540676&file_id=298968&aid=1865300
@@ -228,7 +311,7 @@ inline const char* fast_atof_move(const char * in, f32& result)
 		return 0;
 
 	const bool negative = ('-' == *in);
-	if (negative)
+	if (negative || ('+'==*in))
 		++in;
 
 	f32 value = strtof10(in, &in);
@@ -255,12 +338,18 @@ inline const char* fast_atof_move(const char * in, f32& result)
 }
 
 //! Convert a string to a floating point number
-/** \param floatAsString: The string to convert. 
+/** \param floatAsString The string to convert.
+    \param out Optional pointer to the first character in the string that
+    wasn't used to create the float value.
+    \result Float value parsed from the input string
 */
-inline float fast_atof(const char* floatAsString)
+inline float fast_atof(const char* floatAsString, const char** out=0)
 {
 	float ret;
-	fast_atof_move(floatAsString, ret);
+	if (out)
+		*out=fast_atof_move(floatAsString, ret);
+	else
+		fast_atof_move(floatAsString, ret);
 	return ret;
 }