Rewrite strtof(3).

libc/stdlib/strtod.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -25,6 +25,10 @@
 #define STRTOF_FLOAT double
 #define STRTOF strtod
 #define STRTOF_CHAR char
+#define STRTOF_CTYPE_CHAR unsigned char
 #define STRTOF_L(x) x
+#define STRTOF_ISSPACE isspace
+#define STRTOF_STRNCASECMP strncasecmp
+#define STRTOF_POW pow
 
 #include "strtof.cpp"

libc/stdlib/strtof.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -26,74 +26,178 @@
 #define STRTOF_FLOAT float
 #define STRTOF strtof
 #define STRTOF_CHAR char
+#define STRTOF_CTYPE_CHAR unsigned char
 #define STRTOF_L(x) x
+#define STRTOF_ISSPACE isspace
+#define STRTOF_STRNCASECMP strncasecmp
+#define STRTOF_POW powf
 #endif
 
+#include <ctype.h>
+#include <errno.h>
+#include <math.h>
 #include <stdlib.h>
+#include <string.h>
 #include <wchar.h>
+#include <wctype.h>
 
-// TODO: This horribly hacky code is taken from sdlquake's common.c, which is
+// TODO: This is an imperfect implementation that doesn't try to minimize loss
-//       licensed under the GPL. Since most Sortix software is GPL-compatible
+//       and explicitly handle overflow conditions. It behaves well enough on
-//       this will do for now. It's a temporary measure until I get around to
+//       simple common inputs to do for now.
-//       writing a real strtod function - most of them are true horrors.
 
 #if !defined(__is_sortix_kernel)
+static inline size_t nan_parameter(const STRTOF_CHAR* str)
+{
+	size_t index = 0;
+	if ( str[index++] != STRTOF_L('(') )
+		return 0;
+	// TODO: What exactly does digit and nondigit mean here in POSIX?
+	if ( !str[index] || str[index] == STRTOF_L(')') )
+		return 0;
+	while ( str[index] && str[index] != STRTOF_L(')') )
+		index++;
+	if ( str[index++] != STRTOF_L(')') )
+		return 0;
+	return index;
+}
+
+static inline bool is_hexadecimal_float(const STRTOF_CHAR* str)
+{
+	if ( *str++ != '0' )
+		return false;
+	if ( *str != 'x' && *str != 'X' )
+		return false;
+	str++;
+	if ( *str == '.' )
+		str++;
+	return isxdigit((STRTOF_CTYPE_CHAR) *str);
+}
+
+static inline bool is_exponent(const STRTOF_CHAR* str,
+                               STRTOF_CHAR elc,
+                               STRTOF_CHAR euc)
+{
+	if ( *str != elc && *str != euc )
+		return false;
+	str++;
+	if ( *str == '-' || *str == '+' )
+		str++;
+	return STRTOF_L('0') <= *str && *str <= STRTOF_L('9');
+}
+
+static inline bool parse_digit(const STRTOF_CHAR* str,
+                               int base,
+                               STRTOF_FLOAT* out)
+{
+	if ( STRTOF_L('0') <= *str && *str <= STRTOF_L('9') )
+		return *out = *str - STRTOF_L('0') , true;
+	if ( base == 16 )
+	{
+		if ( STRTOF_L('a') <= *str && *str <= STRTOF_L('f') )
+			return *out = 10 + *str - STRTOF_L('a') , true;
+		if ( STRTOF_L('A') <= *str && *str <= STRTOF_L('F') )
+			return *out = 10 + *str - STRTOF_L('A') , true;
+	}
+	return false;
+}
+
 extern "C" STRTOF_FLOAT STRTOF(const STRTOF_CHAR* str, STRTOF_CHAR** nptr)
 {
-	int sign = *str == STRTOF_L('-') ? (str++, -1) : 1;
+	if ( nptr )
-	STRTOF_FLOAT val = 0.0;
+		*nptr = (STRTOF_CHAR*) str;
 
-	if ( false )
+	while ( *str && STRTOF_ISSPACE((STRTOF_CTYPE_CHAR) *str) )
+		str++;
+
+	if ( !STRTOF_STRNCASECMP(str, STRTOF_L("INF"), 3) )
 	{
-	out:
+		str += 3;
+		if ( !STRTOF_STRNCASECMP(str, STRTOF_L("INITY"), 5) )
+			str += 5;
 		if ( nptr )
 			*nptr = (STRTOF_CHAR*) str;
-		return val * sign;
+		return INFINITY;
 	}
 
-	if ( str[0] == STRTOF_L('0') &&
+	if ( !STRTOF_STRNCASECMP(str, STRTOF_L("NAN"), 3) )
-	     (str[1] == STRTOF_L('x') || str[1] == STRTOF_L('X')) )
+	{
+		str += 3;
+		str += nan_parameter(str);
+		if ( nptr )
+			*nptr = (STRTOF_CHAR*) str;
+		return NAN;
+	}
+
+	bool negative = *str == STRTOF_L('-');
+	if ( *str == STRTOF_L('-') )
+		str++;
+	else if ( *str == STRTOF_L('+') )
+		str++;
+
+	int base = 10;
+	STRTOF_CHAR elc = 'e';
+	STRTOF_CHAR euc = 'E';
+
+	if ( is_hexadecimal_float(str) )
 	{
 		str += 2;
-		while ( true )
+		base = 16;
+		elc = 'p';
+		euc = 'P';
+	}
+
+	bool any_digits = false;
+	STRTOF_FLOAT result = 0.0;
+	STRTOF_FLOAT add;
+
+	while ( parse_digit(str, base, &add) )
+	{
+		str++;
+		result = base * result + add;
+		any_digits = true;
+	}
+
+	if ( *str == STRTOF_L('.' ) )
+	{
+		str++;
+		STRTOF_FLOAT magnitude = 1.0;
+		while ( parse_digit(str, base, &add) )
 		{
-			STRTOF_CHAR c = *str++;
+			str++;
-			if ( STRTOF_L('0') <= c && c <= STRTOF_L('9') )
+			magnitude /= base;
-				val = val * 16 + c - STRTOF_L('0');
+			result += add * magnitude;
-			else if ( STRTOF_L('a') <= c && c <= STRTOF_L('f') )
+			any_digits = true;
-				val = val * 16 + c - STRTOF_L('a') + 10;
-			else if ( STRTOF_L('A') <= c && c <= STRTOF_L('F') )
-				val = val * 16 + c - STRTOF_L('A') + 10;
-			else
-				goto out;
 		}
 	}
 
-	int decimal = -1;
+	if ( !any_digits )
-	int total = 0;
+		return errno = EINVAL, 0;
-	while ( true )
+
+	if ( is_exponent(str, elc, euc) )
 	{
-		STRTOF_CHAR c = *str++;
+		str++;
-		if ( c == STRTOF_L('.') )
+		bool exponent_negative = *str == STRTOF_L('-');
+		if ( *str == STRTOF_L('-') )
+			str++;
+		else if ( *str == STRTOF_L('+') )
+			str++;
+		STRTOF_FLOAT exponent = 0.0;
+		while ( parse_digit(str, 10, &add) )
 		{
-			decimal = total;
+			str++;
-			continue;
+			exponent = 10.0 * exponent + add;
+			any_digits = true;
 		}
-		if ( c < STRTOF_L('0') || c > STRTOF_L('9') )
+		if ( exponent_negative )
-			break;
+			exponent = -exponent;
-		val = val * 10 + c - STRTOF_L('0');
+		result *= STRTOF_POW(base == 16 ? 2 : base, exponent);
-		total++;
 	}
 
-	if ( decimal == -1 )
+	if ( negative )
-		goto out;
+		result = -result;
 
-	while ( decimal < total )
+	if ( nptr )
-	{
+		*nptr = (STRTOF_CHAR*) str;
-		val /= 10;
+	return result;
-		total--;
-	}
-
-	goto out;
 }
 #endif

libc/stdlib/strtold.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -25,6 +25,10 @@
 #define STRTOF_FLOAT long double
 #define STRTOF strtold
 #define STRTOF_CHAR char
+#define STRTOF_CTYPE_CHAR unsigned char
 #define STRTOF_L(x) x
+#define STRTOF_ISSPACE isspace
+#define STRTOF_STRNCASECMP strncasecmp
+#define STRTOF_POW pow /* TODO: powl */
 
 #include "strtof.cpp"

libc/wchar/wcstod.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -25,6 +25,10 @@
 #define STRTOF_FLOAT double
 #define STRTOF wcstod
 #define STRTOF_CHAR wchar_t
+#define STRTOF_CTYPE_CHAR wint_t
 #define STRTOF_L(x) L##x
+#define STRTOF_ISSPACE iswspace
+#define STRTOF_STRNCASECMP wcsncasecmp
+#define STRTOF_POW pow
 
 #include "../stdlib/strtof.cpp"

libc/wchar/wcstof.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -25,6 +25,10 @@
 #define STRTOF_FLOAT float
 #define STRTOF wcstof
 #define STRTOF_CHAR wchar_t
+#define STRTOF_CTYPE_CHAR wint_t
 #define STRTOF_L(x) L##x
+#define STRTOF_ISSPACE iswspace
+#define STRTOF_STRNCASECMP wcsncasecmp
+#define STRTOF_POW powf
 
 #include "../stdlib/strtof.cpp"

libc/wchar/wcstold.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2014.
+    Copyright(C) Jonas 'Sortie' Termansen 2016.
 
     This file is part of the Sortix C Library.
 
@@ -25,6 +25,10 @@
 #define STRTOF_FLOAT long double
 #define STRTOF wcstold
 #define STRTOF_CHAR wchar_t
+#define STRTOF_CTYPE_CHAR wint_t
 #define STRTOF_L(x) L##x
+#define STRTOF_ISSPACE iswspace
+#define STRTOF_STRNCASECMP wcsncasecmp
+#define STRTOF_POW pow /* TODO: powl */
 
 #include "../stdlib/strtof.cpp"