splitting util.c

Message-Id: <200106132341.AAA24935@crypt.compulink.co.uk>

p4raw-id: //depot/perl@10579

1 files changed, 691 insertions, 0 deletions

diff --git a/numeric.c b/numeric.c
new file mode 100644
index 0000000000..a22f813e64
--- /dev/null
+++ b/numeric.c
@@ -0,0 +1,691 @@
+/*    numeric.c
+ *
+ *    Copyright (c) 2001, Larry Wall
+ *
+ *    You may distribute under the terms of either the GNU General Public
+ *    License or the Artistic License, as specified in the README file.
+ *
+ */
+
+/*
+ * "That only makes eleven (plus one mislaid) and not fourteen, unless
+ * wizards count differently to other people."
+ */
+
+#include "EXTERN.h"
+#define PERL_IN_NUMERIC_C
+#include "perl.h"
+
+U32
+Perl_cast_ulong(pTHX_ NV f)
+{
+  if (f < 0.0)
+    return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f;
+  if (f < U32_MAX_P1) {
+#if CASTFLAGS & 2
+    if (f < U32_MAX_P1_HALF)
+      return (U32) f;
+    f -= U32_MAX_P1_HALF;
+    return ((U32) f) | (1 + U32_MAX >> 1);
+#else
+    return (U32) f;
+#endif
+  }
+  return f > 0 ? U32_MAX : 0 /* NaN */;
+}
+
+I32
+Perl_cast_i32(pTHX_ NV f)
+{
+  if (f < I32_MAX_P1)
+    return f < I32_MIN ? I32_MIN : (I32) f;
+  if (f < U32_MAX_P1) {
+#if CASTFLAGS & 2
+    if (f < U32_MAX_P1_HALF)
+      return (I32)(U32) f;
+    f -= U32_MAX_P1_HALF;
+    return (I32)(((U32) f) | (1 + U32_MAX >> 1));
+#else
+    return (I32)(U32) f;
+#endif
+  }
+  return f > 0 ? (I32)U32_MAX : 0 /* NaN */;
+}
+
+IV
+Perl_cast_iv(pTHX_ NV f)
+{
+  if (f < IV_MAX_P1)
+    return f < IV_MIN ? IV_MIN : (IV) f;
+  if (f < UV_MAX_P1) {
+#if CASTFLAGS & 2
+    /* For future flexibility allowing for sizeof(UV) >= sizeof(IV)  */
+    if (f < UV_MAX_P1_HALF)
+      return (IV)(UV) f;
+    f -= UV_MAX_P1_HALF;
+    return (IV)(((UV) f) | (1 + UV_MAX >> 1));
+#else
+    return (IV)(UV) f;
+#endif
+  }
+  return f > 0 ? (IV)UV_MAX : 0 /* NaN */;
+}
+
+UV
+Perl_cast_uv(pTHX_ NV f)
+{
+  if (f < 0.0)
+    return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f;
+  if (f < UV_MAX_P1) {
+#if CASTFLAGS & 2
+    if (f < UV_MAX_P1_HALF)
+      return (UV) f;
+    f -= UV_MAX_P1_HALF;
+    return ((UV) f) | (1 + UV_MAX >> 1);
+#else
+    return (UV) f;
+#endif
+  }
+  return f > 0 ? UV_MAX : 0 /* NaN */;
+}
+
+#if defined(HUGE_VAL) || (defined(USE_LONG_DOUBLE) && defined(HUGE_VALL))
+/*
+ * This hack is to force load of "huge" support from libm.a
+ * So it is in perl for (say) POSIX to use.
+ * Needed for SunOS with Sun's 'acc' for example.
+ */
+NV
+Perl_huge(void)
+{
+#   if defined(USE_LONG_DOUBLE) && defined(HUGE_VALL)
+    return HUGE_VALL;
+#   endif
+    return HUGE_VAL;
+}
+#endif
+
+NV
+Perl_scan_bin(pTHX_ char *start, STRLEN len, STRLEN *retlen)
+{
+    register char *s = start;
+    register NV rnv = 0.0;
+    register UV ruv = 0;
+    register bool seenb = FALSE;
+    register bool overflowed = FALSE;
+
+    for (; len-- && *s; s++) {
+	if (!(*s == '0' || *s == '1')) {
+	    if (*s == '_' && len && *retlen
+		&& (s[1] == '0' || s[1] == '1'))
+	    {
+		--len;
+		++s;
+	    }
+	    else if (seenb == FALSE && *s == 'b' && ruv == 0) {
+		/* Disallow 0bbb0b0bbb... */
+		seenb = TRUE;
+		continue;
+	    }
+	    else {
+		if (ckWARN(WARN_DIGIT))
+		    Perl_warner(aTHX_ WARN_DIGIT,
+				"Illegal binary digit '%c' ignored", *s);
+		break;
+	    }
+	}
+	if (!overflowed) {
+	    register UV xuv = ruv << 1;
+
+	    if ((xuv >> 1) != ruv) {
+		overflowed = TRUE;
+		rnv = (NV) ruv;
+		if (ckWARN_d(WARN_OVERFLOW))
+		    Perl_warner(aTHX_ WARN_OVERFLOW,
+				"Integer overflow in binary number");
+	    }
+	    else
+		ruv = xuv | (*s - '0');
+	}
+	if (overflowed) {
+	    rnv *= 2;
+	    /* If an NV has not enough bits in its mantissa to
+	     * represent an UV this summing of small low-order numbers
+	     * is a waste of time (because the NV cannot preserve
+	     * the low-order bits anyway): we could just remember when
+	     * did we overflow and in the end just multiply rnv by the
+	     * right amount. */
+	    rnv += (*s - '0');
+	}
+    }
+    if (!overflowed)
+	rnv = (NV) ruv;
+    if (   ( overflowed && rnv > 4294967295.0)
+#if UVSIZE > 4
+	|| (!overflowed && ruv > 0xffffffff  )
+#endif
+	) {
+	if (ckWARN(WARN_PORTABLE))
+	    Perl_warner(aTHX_ WARN_PORTABLE,
+			"Binary number > 0b11111111111111111111111111111111 non-portable");
+    }
+    *retlen = s - start;
+    return rnv;
+}
+
+NV
+Perl_scan_oct(pTHX_ char *start, STRLEN len, STRLEN *retlen)
+{
+    register char *s = start;
+    register NV rnv = 0.0;
+    register UV ruv = 0;
+    register bool overflowed = FALSE;
+
+    for (; len-- && *s; s++) {
+	if (!(*s >= '0' && *s <= '7')) {
+	    if (*s == '_' && len && *retlen
+		&& (s[1] >= '0' && s[1] <= '7'))
+	    {
+		--len;
+		++s;
+	    }
+	    else {
+		/* Allow \octal to work the DWIM way (that is, stop scanning
+		 * as soon as non-octal characters are seen, complain only iff
+		 * someone seems to want to use the digits eight and nine). */
+		if (*s == '8' || *s == '9') {
+		    if (ckWARN(WARN_DIGIT))
+			Perl_warner(aTHX_ WARN_DIGIT,
+				    "Illegal octal digit '%c' ignored", *s);
+		}
+		break;
+	    }
+	}
+	if (!overflowed) {
+	    register UV xuv = ruv << 3;
+
+	    if ((xuv >> 3) != ruv) {
+		overflowed = TRUE;
+		rnv = (NV) ruv;
+		if (ckWARN_d(WARN_OVERFLOW))
+		    Perl_warner(aTHX_ WARN_OVERFLOW,
+				"Integer overflow in octal number");
+	    }
+	    else
+		ruv = xuv | (*s - '0');
+	}
+	if (overflowed) {
+	    rnv *= 8.0;
+	    /* If an NV has not enough bits in its mantissa to
+	     * represent an UV this summing of small low-order numbers
+	     * is a waste of time (because the NV cannot preserve
+	     * the low-order bits anyway): we could just remember when
+	     * did we overflow and in the end just multiply rnv by the
+	     * right amount of 8-tuples. */
+	    rnv += (NV)(*s - '0');
+	}
+    }
+    if (!overflowed)
+	rnv = (NV) ruv;
+    if (   ( overflowed && rnv > 4294967295.0)
+#if UVSIZE > 4
+	|| (!overflowed && ruv > 0xffffffff  )
+#endif
+	) {
+	if (ckWARN(WARN_PORTABLE))
+	    Perl_warner(aTHX_ WARN_PORTABLE,
+			"Octal number > 037777777777 non-portable");
+    }
+    *retlen = s - start;
+    return rnv;
+}
+
+NV
+Perl_scan_hex(pTHX_ char *start, STRLEN len, STRLEN *retlen)
+{
+    register char *s = start;
+    register NV rnv = 0.0;
+    register UV ruv = 0;
+    register bool overflowed = FALSE;
+    char *hexdigit;
+
+    if (len > 2) {
+	if (s[0] == 'x') {
+	    s++;
+	    len--;
+	}
+	else if (len > 3 && s[0] == '0' && s[1] == 'x') {
+	    s+=2;
+	    len-=2;
+	}
+    }
+
+    for (; len-- && *s; s++) {
+	hexdigit = strchr((char *) PL_hexdigit, *s);
+	if (!hexdigit) {
+	    if (*s == '_' && len && *retlen && s[1]
+		&& (hexdigit = strchr((char *) PL_hexdigit, s[1])))
+	    {
+		--len;
+		++s;
+	    }
+	    else {
+		if (ckWARN(WARN_DIGIT))
+		    Perl_warner(aTHX_ WARN_DIGIT,
+				"Illegal hexadecimal digit '%c' ignored", *s);
+		break;
+	    }
+	}
+	if (!overflowed) {
+	    register UV xuv = ruv << 4;
+
+	    if ((xuv >> 4) != ruv) {
+		overflowed = TRUE;
+		rnv = (NV) ruv;
+		if (ckWARN_d(WARN_OVERFLOW))
+		    Perl_warner(aTHX_ WARN_OVERFLOW,
+				"Integer overflow in hexadecimal number");
+	    }
+	    else
+		ruv = xuv | ((hexdigit - PL_hexdigit) & 15);
+	}
+	if (overflowed) {
+	    rnv *= 16.0;
+	    /* If an NV has not enough bits in its mantissa to
+	     * represent an UV this summing of small low-order numbers
+	     * is a waste of time (because the NV cannot preserve
+	     * the low-order bits anyway): we could just remember when
+	     * did we overflow and in the end just multiply rnv by the
+	     * right amount of 16-tuples. */
+	    rnv += (NV)((hexdigit - PL_hexdigit) & 15);
+	}
+    }
+    if (!overflowed)
+	rnv = (NV) ruv;
+    if (   ( overflowed && rnv > 4294967295.0)
+#if UVSIZE > 4
+	|| (!overflowed && ruv > 0xffffffff  )
+#endif
+	) {
+	if (ckWARN(WARN_PORTABLE))
+	    Perl_warner(aTHX_ WARN_PORTABLE,
+			"Hexadecimal number > 0xffffffff non-portable");
+    }
+    *retlen = s - start;
+    return rnv;
+}
+
+/*
+=for apidoc grok_numeric_radix
+
+Scan and skip for a numeric decimal separator (radix).
+
+=cut
+ */
+bool
+Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send)
+{
+#ifdef USE_LOCALE_NUMERIC
+    if (PL_numeric_radix_sv && IN_LOCALE) { 
+        STRLEN len;
+        char* radix = SvPV(PL_numeric_radix_sv, len);
+        if (*sp + len <= send && memEQ(*sp, radix, len)) {
+            *sp += len;
+            return TRUE; 
+        }
+    }
+    /* always try "." if numeric radix didn't match because
+     * we may have data from different locales mixed */
+#endif
+    if (*sp < send && **sp == '.') {
+        ++*sp;
+        return TRUE;
+    }
+    return FALSE;
+}
+
+/*
+=for apidoc grok_number
+
+Recognise (or not) a number.  The type of the number is returned
+(0 if unrecognised), otherwise it is a bit-ORed combination of
+IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT,
+IS_NUMBER_NEG, IS_NUMBER_INFINITY (defined in perl.h).  If the value
+of the number can fit an in UV, it is returned in the *valuep.
+
+=cut
+ */
+int
+Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep)
+{
+    const char *s = pv;
+    const char *send = pv + len;
+    const UV max_div_10 = UV_MAX / 10;
+    const char max_mod_10 = UV_MAX % 10 + '0';
+    int numtype = 0;
+    int sawinf = 0;
+
+    while (isSPACE(*s))
+	s++;
+    if (*s == '-') {
+	s++;
+	numtype = IS_NUMBER_NEG;
+    }
+    else if (*s == '+')
+	s++;
+
+    /* next must be digit or the radix separator or beginning of infinity */
+    if (isDIGIT(*s)) {
+	/* UVs are at least 32 bits, so the first 9 decimal digits cannot
+	   overflow.  */
+	UV value = *s - '0';
+	/* This construction seems to be more optimiser friendly.
+	   (without it gcc does the isDIGIT test and the *s - '0' separately)
+	   With it gcc on arm is managing 6 instructions (6 cycles) per digit.
+	   In theory the optimiser could deduce how far to unroll the loop
+	   before checking for overflow.  */
+	int digit = *++s - '0';
+	if (digit >= 0 && digit <= 9) {
+	    value = value * 10 + digit;
+	    digit = *++s - '0';
+	    if (digit >= 0 && digit <= 9) {
+		value = value * 10 + digit;
+		digit = *++s - '0';
+		if (digit >= 0 && digit <= 9) {
+		    value = value * 10 + digit;
+		    digit = *++s - '0';
+		    if (digit >= 0 && digit <= 9) {
+			value = value * 10 + digit;
+			digit = *++s - '0';
+			if (digit >= 0 && digit <= 9) {
+			    value = value * 10 + digit;
+			    digit = *++s - '0';
+			    if (digit >= 0 && digit <= 9) {
+				value = value * 10 + digit;
+				digit = *++s - '0';
+				if (digit >= 0 && digit <= 9) {
+				    value = value * 10 + digit;
+				    digit = *++s - '0';
+				    if (digit >= 0 && digit <= 9) {
+					value = value * 10 + digit;
+					/* Now got 9 digits, so need to check
+					   each time for overflow.  */
+					digit = *++s - '0';
+					while (digit >= 0 && digit <= 9
+					       && (value < max_div_10
+						   || (value == max_div_10
+						       && *s <= max_mod_10))) {
+					    value = value * 10 + digit;
+					    digit = *++s - '0';
+					}
+					if (digit >= 0 && digit <= 9) {
+					    /* value overflowed.
+					       skip the remaining digits, don't
+					       worry about setting *valuep.  */
+					    do {
+						s++;
+					    } while (isDIGIT(*s));
+					    numtype |=
+						IS_NUMBER_GREATER_THAN_UV_MAX;
+					    goto skip_value;
+					}
+				    }
+				}
+			    }
+			}
+		    }
+		}
+	    }
+	}
+	numtype |= IS_NUMBER_IN_UV;
+	if (valuep)
+	    *valuep = value;
+
+      skip_value:
+	if (GROK_NUMERIC_RADIX(&s, send)) {
+	    numtype |= IS_NUMBER_NOT_INT;
+	    while (isDIGIT(*s))  /* optional digits after the radix */
+	        s++;
+	}
+    }
+    else if (GROK_NUMERIC_RADIX(&s, send)) {
+        numtype |= IS_NUMBER_NOT_INT;
+	/* no digits before the radix means we need digits after it */
+	if (isDIGIT(*s)) {
+	    do {
+	        s++;
+	    } while (isDIGIT(*s));
+	    numtype |= IS_NUMBER_IN_UV;
+	    if (valuep) {
+	        /* integer approximation is valid - it's 0.  */
+	        *valuep = 0;
+	    }
+	}
+	else
+	    return 0;
+    }
+    else if (*s == 'I' || *s == 'i') {
+        s++; if (*s != 'N' && *s != 'n') return 0;
+	s++; if (*s != 'F' && *s != 'f') return 0;
+	s++; if (*s == 'I' || *s == 'i') {
+	    s++; if (*s != 'N' && *s != 'n') return 0;
+	    s++; if (*s != 'I' && *s != 'i') return 0;
+	    s++; if (*s != 'T' && *s != 't') return 0;
+	    s++; if (*s != 'Y' && *s != 'y') return 0;
+	    s++;
+	}
+	sawinf = 1;
+    }
+    else /* Add test for NaN here.  */
+        return 0;
+
+    if (sawinf) {
+	numtype &= IS_NUMBER_NEG; /* Keep track of sign  */
+	numtype |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT;
+    } else {
+	/* we can have an optional exponent part */
+	if (*s == 'e' || *s == 'E') {
+            /* The only flag we keep is sign.  Blow away any "it's UV"  */
+	    numtype &= IS_NUMBER_NEG;
+	    numtype |= IS_NUMBER_NOT_INT;
+	    s++;
+	    if (*s == '-' || *s == '+')
+		s++;
+	    if (isDIGIT(*s)) {
+		do {
+		    s++;
+		} while (isDIGIT(*s));
+	    }
+	    else
+		return 0;
+	}
+    }
+    while (isSPACE(*s))
+	s++;
+    if (s >= send)
+	return numtype;
+    if (len == 10 && memEQ(pv, "0 but true", 10)) {
+	if (valuep)
+	    *valuep = 0;
+	return IS_NUMBER_IN_UV;
+    }
+    return 0;
+}
+
+NV
+S_mulexp10(NV value, I32 exponent)
+{
+    NV result = 1.0;
+    NV power = 10.0;
+    bool negative = 0;
+    I32 bit;
+
+    if (exponent == 0)
+	return value;
+    else if (exponent < 0) {
+	negative = 1;
+	exponent = -exponent;
+    }
+    for (bit = 1; exponent; bit <<= 1) {
+	if (exponent & bit) {
+	    exponent ^= bit;
+	    result *= power;
+	}
+	power *= power;
+    }
+    return negative ? value / result : value * result;
+}
+
+NV
+Perl_my_atof(pTHX_ const char* s)
+{
+    NV x = 0.0;
+#ifdef USE_LOCALE_NUMERIC
+    if (PL_numeric_local && IN_LOCALE) {
+	NV y;
+
+	/* Scan the number twice; once using locale and once without;
+	 * choose the larger result (in absolute value). */
+	Perl_atof2(aTHX_ s, &x);
+	SET_NUMERIC_STANDARD();
+	Perl_atof2(aTHX_ s, &y);
+	SET_NUMERIC_LOCAL();
+	if ((y < 0.0 && y < x) || (y > 0.0 && y > x))
+	    return y;
+    }
+    else
+	Perl_atof2(aTHX_ s, &x);
+#else
+    Perl_atof2(aTHX_ s, &x);
+#endif
+    return x;
+}
+
+char*
+Perl_my_atof2(pTHX_ const char* orig, NV* value)
+{
+    NV result = 0.0;
+    bool negative = 0;
+    char* s = (char*)orig;
+    char* send = s + strlen(orig) - 1;
+    bool seendigit = 0;
+    I32 expextra = 0;
+    I32 exponent = 0;
+    I32 i;
+/* this is arbitrary */
+#define PARTLIM 6
+/* we want the largest integers we can usefully use */
+#if defined(HAS_QUAD) && defined(USE_64_BIT_INT)
+#   define PARTSIZE ((int)TYPE_DIGITS(U64)-1)
+    U64 part[PARTLIM];
+#else
+#   define PARTSIZE ((int)TYPE_DIGITS(U32)-1)
+    U32 part[PARTLIM];
+#endif
+    I32 ipart = 0;	/* index into part[] */
+    I32 offcount;	/* number of digits in least significant part */
+
+    /* sign */
+    switch (*s) {
+	case '-':
+	    negative = 1;
+	    /* fall through */
+	case '+':
+	    ++s;
+    }
+
+    part[0] = offcount = 0;
+    if (isDIGIT(*s)) {
+	seendigit = 1;	/* get this over with */
+
+	/* skip leading zeros */
+	while (*s == '0')
+	    ++s;
+    }
+
+    /* integer digits */
+    while (isDIGIT(*s)) {
+	if (++offcount > PARTSIZE) {
+	    if (++ipart < PARTLIM) {
+		part[ipart] = 0;
+		offcount = 1;	/* ++0 */
+	    }
+	    else {
+		/* limits of precision reached */
+		--ipart;
+		--offcount;
+		if (*s >= '5')
+		    ++part[ipart];
+		while (isDIGIT(*s)) {
+		    ++expextra;
+		    ++s;
+		}
+		/* warn of loss of precision? */
+		break;
+	    }
+	}
+	part[ipart] = part[ipart] * 10 + (*s++ - '0');
+    }
+
+    /* decimal point */
+    if (GROK_NUMERIC_RADIX((const char **)&s, send)) {
+	if (isDIGIT(*s))
+	    seendigit = 1;	/* get this over with */
+
+	/* decimal digits */
+	while (isDIGIT(*s)) {
+	    if (++offcount > PARTSIZE) {
+		if (++ipart < PARTLIM) {
+		    part[ipart] = 0;
+		    offcount = 1;	/* ++0 */
+		}
+		else {
+		    /* limits of precision reached */
+		    --ipart;
+		    --offcount;
+		    if (*s >= '5')
+			++part[ipart];
+		    while (isDIGIT(*s))
+			++s;
+		    /* warn of loss of precision? */
+		    break;
+		}
+	    }
+	    --expextra;
+	    part[ipart] = part[ipart] * 10 + (*s++ - '0');
+	}
+    }
+
+    /* combine components of mantissa */
+    for (i = 0; i <= ipart; ++i)
+	result += S_mulexp10((NV)part[ipart - i],
+		i ? offcount + (i - 1) * PARTSIZE : 0);
+
+    if (seendigit && (*s == 'e' || *s == 'E')) {
+	bool expnegative = 0;
+
+	++s;
+	switch (*s) {
+	    case '-':
+		expnegative = 1;
+		/* fall through */
+	    case '+':
+		++s;
+	}
+	while (isDIGIT(*s))
+	    exponent = exponent * 10 + (*s++ - '0');
+	if (expnegative)
+	    exponent = -exponent;
+    }
+
+    /* now apply the exponent */
+    exponent += expextra;
+    result = S_mulexp10(result, exponent);
+
+    /* now apply the sign */
+    if (negative)
+	result = -result;
+    *value = result;
+    return s;
+}
+