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authornaruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2010-04-01 04:32:57 (GMT)
committernaruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2010-04-01 04:32:57 (GMT)
commit12b2e16e21bbd7f0b6fd12c7e21cba4d42e284ad (patch)
tree20346cc6c455bba7684139a3c2af88806a9ba7b4 /util.c
parent4d399f12d4354c17bbb1ea2b12de4c11c6ac03ff (diff)
* sprintf.c (rb_str_format): support %a format. [ruby-dev:40650]
* missing/vsnprintf.c (BSD_vfprintf): ditto. * missing/vsnprintf.c (cvt): ditto. * util.c (BSD__hdtoa): added. This is 2-clause BSDL licensed by David Schultz and from FreeBSD. * LEGAL: add about hdtoa() in util.c. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@27141 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'util.c')
-rw-r--r--util.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/util.c b/util.c
index 11d0272..88914be 100644
--- a/util.c
+++ b/util.c
@@ -3857,6 +3857,149 @@ ruby_each_words(const char *str, void (*func)(const char*, int, void*), void *ar
}
}
+/*-
+ * Copyright (c) 2004-2008 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#define DBL_MANH_SIZE 20
+#define DBL_MANL_SIZE 32
+#define INFSTR "Infinity"
+#define NANSTR "NaN"
+#define DBL_ADJ (DBL_MAX_EXP - 2)
+#define SIGFIGS ((DBL_MANT_DIG + 3) / 4 + 1)
+#define dexp_get(u) ((int)(word0(u) >> Exp_shift) & ~Exp_msk1)
+#define dexp_set(u,v) (word0(u) = (((int)(word0(u)) & ~Exp_mask) | (v << Exp_shift)))
+#define dmanh_get(u) ((int)(word0(u) & Frac_mask))
+#define dmanl_get(u) ((int)word1(u))
+
+
+/*
+ * This procedure converts a double-precision number in IEEE format
+ * into a string of hexadecimal digits and an exponent of 2. Its
+ * behavior is bug-for-bug compatible with dtoa() in mode 2, with the
+ * following exceptions:
+ *
+ * - An ndigits < 0 causes it to use as many digits as necessary to
+ * represent the number exactly.
+ * - The additional xdigs argument should point to either the string
+ * "0123456789ABCDEF" or the string "0123456789abcdef", depending on
+ * which case is desired.
+ * - This routine does not repeat dtoa's mistake of setting decpt
+ * to 9999 in the case of an infinity or NaN. INT_MAX is used
+ * for this purpose instead.
+ *
+ * Note that the C99 standard does not specify what the leading digit
+ * should be for non-zero numbers. For instance, 0x1.3p3 is the same
+ * as 0x2.6p2 is the same as 0x4.cp3. This implementation always makes
+ * the leading digit a 1. This ensures that the exponent printed is the
+ * actual base-2 exponent, i.e., ilogb(d).
+ *
+ * Inputs: d, xdigs, ndigits
+ * Outputs: decpt, sign, rve
+ */
+char *
+BSD__hdtoa(double d, const char *xdigs, int ndigits, int *decpt, int *sign,
+ char **rve)
+{
+ U u;
+ char *s, *s0;
+ int bufsize;
+ uint32_t manh, manl;
+
+ u.d = d;
+ if (word0(u) & Sign_bit) {
+ /* set sign for everything, including 0's and NaNs */
+ *sign = 1;
+ word0(u) &= ~Sign_bit; /* clear sign bit */
+ }
+ else
+ *sign = 0;
+
+ switch (fpclassify(d)) {
+ case FP_NORMAL:
+ *decpt = dexp_get(u) - DBL_ADJ;
+ break;
+ case FP_ZERO:
+ *decpt = 1;
+ return (nrv_alloc("0", rve, 1));
+ case FP_SUBNORMAL:
+ u.d *= 5.363123171977039e+154 /* 0x1p514 */;
+ *decpt = dexp_get(u) - (514 + DBL_ADJ);
+ break;
+ case FP_INFINITE:
+ *decpt = INT_MAX;
+ return (nrv_alloc(INFSTR, rve, sizeof(INFSTR) - 1));
+ default: /* FP_NAN or unrecognized */
+ *decpt = INT_MAX;
+ return (nrv_alloc(NANSTR, rve, sizeof(NANSTR) - 1));
+ }
+
+ /* FP_NORMAL or FP_SUBNORMAL */
+
+ if (ndigits == 0) /* dtoa() compatibility */
+ ndigits = 1;
+
+ /*
+ * If ndigits < 0, we are expected to auto-size, so we allocate
+ * enough space for all the digits.
+ */
+ bufsize = (ndigits > 0) ? ndigits : SIGFIGS;
+ s0 = rv_alloc(bufsize);
+
+ /* Round to the desired number of digits. */
+ if (SIGFIGS > ndigits && ndigits > 0) {
+ float redux = 1.0;
+ int offset = 4 * ndigits + DBL_MAX_EXP - 4 - DBL_MANT_DIG;
+ dexp_set(u, offset);
+ u.d += redux;
+ u.d -= redux;
+ *decpt += dexp_get(u) - offset;
+ }
+
+ manh = dmanh_get(u);
+ manl = dmanl_get(u);
+ *s0 = '1';
+ for (s = s0 + 1; s < s0 + bufsize; s++) {
+ *s = xdigs[(manh >> (DBL_MANH_SIZE - 4)) & 0xf];
+ manh = (manh << 4) | (manl >> (DBL_MANL_SIZE - 4));
+ manl <<= 4;
+ }
+
+ /* If ndigits < 0, we are expected to auto-size the precision. */
+ if (ndigits < 0) {
+ for (ndigits = SIGFIGS; s0[ndigits - 1] == '0'; ndigits--)
+ ;
+ }
+
+ s = s0 + ndigits;
+ *s = '\0';
+ if (rve != NULL)
+ *rve = s;
+ return (s0);
+}
+
#ifdef __cplusplus
#if 0
{