clean up fpinfo a little bit.

include/endian.h

@@ -21,7 +21,7 @@
 #define bswap32 __builtin_bswap32
 #define bswap64 __builtin_bswap64
 
-#if _BYTE_ORDER == _LITTLE_ENDIAN
+#if BYTE_ORDER == LITTLE_ENDIAN
 #define	htobe16(x)	bswap16((x))
 #define	htobe32(x)	bswap32((x))
 #define	htobe64(x)	bswap64((x))
@@ -35,7 +35,7 @@
 #define	le16toh(x)	((uint16_t)(x))
 #define	le32toh(x)	((uint32_t)(x))
 #define	le64toh(x)	((uint64_t)(x))
-#else /* _BYTE_ORDER != _LITTLE_ENDIAN */
+#else /* BYTE_ORDER != LITTLE_ENDIAN */
 #define	htobe16(x)	((uint16_t)(x))
 #define	htobe32(x)	((uint32_t)(x))
 #define	htobe64(x)	((uint64_t)(x))
@@ -49,7 +49,28 @@
 #define	le16toh(x)	bswap16((x))
 #define	le32toh(x)	bswap32((x))
 #define	le64toh(x)	bswap64((x))
-#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
+#endif /* BYTE_ORDER == LITTLE_ENDIAN */
+
+#endif
+
+
+#ifdef __cplusplus
+
+// https://github.com/HowardHinnant/hash_append/blob/master/endian.h
+enum class endian
+{
+    native = LITTLE_ENDIAN,
+    little = LITTLE_ENDIAN,
+    big    = BIG_ENDIAN
+};
+
+static_assert(endian::native == endian::little ||
+              endian::native == endian::big,
+              "endian::native shall be one of endian::little or endian::big");
+
+static_assert(endian::big != endian::little,
+              "endian::big and endian::little shall have different values");
+
 
 #endif
 

toolbox/fpinfo.cpp

@@ -7,6 +7,154 @@ static_assert(sizeof(float) == 4, "Unexpected float size");
 static_assert(sizeof(double) == 8, "Unexpected double size");
 static_assert(sizeof(long double) == 8 || sizeof(long double) == 12 || sizeof(long double) == 16, "Unexpected long double size");
 
+
+namespace {
+
+
+	template<int size>
+	void init(const void *vp, fpinfo &info);
+
+	// 32-bit float
+	template<>
+	void init<4>(const void *vp, fpinfo &info) {
+
+
+		uint32_t i = *(uint32_t *)vp;
+
+		info.sign = i >> 31;
+		info.one = 1;
+		info.exp = (i >> 23) & ((1 << 8) - 1);
+		info.sig = i & ((1 << 24) - 1);
+
+		if (info.exp == 255) {
+			if (info.sig == 0) info.inf = true;
+			else info.nan = true;
+			return;
+		}
+
+		if (info.exp == 0) {
+			// 0 or denormalized.
+			info.one = 0;
+			info.exp = -126;
+			return;
+		}
+
+		info.exp -= 127; // bias
+	}
+
+	// 64-bit double or long double.
+	template<>
+	void init<8>(const void *vp, fpinfo &info) {
+
+		uint64_t i = *(uint64_t *)vp;
+
+		info.sign = i >> 63;
+		info.one = 1;
+		info.exp = (i >> 52) & ((1 << 11) - 1);
+		info.sig = i & ((UINT64_C(1) << 53) - 1);
+
+
+		if (info.exp == 2047) {
+			if (info.sig == 0) info.inf = true;
+			else info.nan = true;
+			return;
+		}
+
+		if (info.exp == 0) {
+			// 0 or denormalized.
+			info.one = 0;
+			info.exp = -1022;
+			return;
+		}
+
+		info.exp -= 1023; // bias
+	}
+
+	/* solaris - 96-bit long double. */
+	template<>
+	void init<12>(const void *vp, fpinfo &info) {
+
+
+		uint64_t i;
+		uint32_t sexp;
+
+
+		// this needs to be verified.
+		#if BYTE_ORDER == LITTLE_ENDIAN
+		i = ((uint64_t *)vp)[0];
+		sexp = ((uint32_t *)vp)[2] & 0xffff;
+		#else
+		#error "please verify big-endian long double format."
+		sexp = *((uint32_t *)vp) & 0xffff;
+		i = *((uint64_t *)((uint8_t *)vp+4);
+		#endif
+
+		info.sign = (sexp >> 15) & 0x01;
+		info.exp = sexp & ((1 << 15) - 1);
+
+		info.one = i >> 63;
+		info.sig = i & ((UINT64_C(1) << 63) - 1);
+
+		if (info.exp == 32767) {
+			if (info.sig == 0) info.inf = true;
+			else info.nan = true;
+			return;
+		}
+		// 
+
+		info.exp -= 16383;
+
+	}
+
+	/* 128-bit long double. same format as 96 but extra padding */
+	template<>
+	void init<16>(const void *vp, fpinfo &info) {
+
+		uint64_t i;
+		uint32_t sexp;
+
+
+		// this needs to be verified.
+		#if BYTE_ORDER == LITTLE_ENDIAN
+		i = ((uint64_t *)vp)[0];
+		sexp = ((uint32_t *)vp)[2] & 0xffff;
+		#else
+		#error "please verify big-endian long double format."
+		i = ((uint64_t *)vp)[1];
+		sexp = ((uint64_t *)vp)[0] & 0xffff;
+		#endif
+
+		info.sign = (sexp >> 15) & 0x01;
+		info.exp = sexp & ((1 << 15) - 1);
+
+		info.one = i >> 63;
+		info.sig = i & ((UINT64_C(1) << 63) - 1);
+
+		if (info.exp == 32767) {
+			if (info.sig == 0) info.inf = true;
+			else info.nan = true;
+			return;
+		}
+		// 
+
+		info.exp -= 16383;
+	}
+
+
+}
+
+fpinfo::fpinfo(const float &f) {
+	init<sizeof(f)>(&f, *this);
+}
+fpinfo::fpinfo(const double &d) {
+	init<sizeof(d)>(&d, *this);
+
+}
+fpinfo::fpinfo(const long double &ld) {
+	init<sizeof(ld)>(&ld, *this);
+}
+
+#if 0
 void fpinfo::init(float *f)
 {
 	union split {
@@ -104,3 +252,5 @@ void fpinfo::init(long double *ld)
 
 	exp -= 16383;
 }
+
+#endif

toolbox/fpinfo.h

@@ -4,6 +4,16 @@
 #include <cstdint>
 
 struct fpinfo {
+
+private:
+	/*
+	void init(float *);
+	void init(double *);
+	void init(long double *);
+	*/
+
+public:
+
 	bool sign = false;
 	bool one = false;
 	int exp = 0;
@@ -12,17 +22,9 @@ struct fpinfo {
 	bool nan = false;
 	bool inf = false;
 
-	fpinfo(float f) { init(&f); }
-	fpinfo(double d) { init(&d); }
-	fpinfo(long double ld) {
-		if (sizeof(long double) == 16 || sizeof(long double) == 12) init(&ld);
-		if (sizeof(long double) == 8) init((double *)&ld);
-	}
-
-private:
-	void init(float *);
-	void init(double *);
-	void init(long double *);
+	fpinfo(const float &f);
+	fpinfo(const double &d);
+	fpinfo(const long double &ld);
 };
 
 

toolbox/sane.cpp

@@ -167,7 +167,7 @@ using its_complicated::signbit;
 	template<>
 	long double readnum<long double>(uint32_t address)
 	{
-		char buffer[16];
+		uint8_t buffer[16];
 
 		static_assert(sizeof(long double) == 16 || sizeof(long double) == 12, "unexpected long double size");
 
@@ -237,7 +237,7 @@ using its_complicated::signbit;
 	{
 		static_assert(sizeof(value) == 16 || sizeof(value) == 12, "unexpected long double size");
 
-		char buffer[16];
+		uint8_t buffer[16];
 
 		std::memcpy(buffer, &value, sizeof(value));