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util.c
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util.c
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/**********************************************************************
util.c -
$Author$
created at: Fri Mar 10 17:22:34 JST 1995
Copyright (C) 1993-2008 Yukihiro Matsumoto
**********************************************************************/
#if defined __MINGW32__ || defined __MINGW64__
#define MINGW_HAS_SECURE_API 1
#endif
#include "internal.h"
#include <ctype.h>
#include <stdio.h>
#include <errno.h>
#include <math.h>
#include <float.h>
#ifdef _WIN32
#include "missing/file.h"
#endif
#include "ruby/util.h"
const char ruby_hexdigits[] = "0123456789abcdef0123456789ABCDEF";
#define hexdigit ruby_hexdigits
unsigned long
ruby_scan_oct(const char *start, size_t len, size_t *retlen)
{
register const char *s = start;
register unsigned long retval = 0;
while (len-- && *s >= '0' && *s <= '7') {
retval <<= 3;
retval |= *s++ - '0';
}
*retlen = (int)(s - start); /* less than len */
return retval;
}
unsigned long
ruby_scan_hex(const char *start, size_t len, size_t *retlen)
{
register const char *s = start;
register unsigned long retval = 0;
const char *tmp;
while (len-- && *s && (tmp = strchr(hexdigit, *s))) {
retval <<= 4;
retval |= (tmp - hexdigit) & 15;
s++;
}
*retlen = (int)(s - start); /* less than len */
return retval;
}
const signed char ruby_digit36_to_number_table[] = {
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
/*0*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*1*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*2*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*3*/ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1,-1,-1,-1,-1,
/*4*/ -1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
/*5*/ 25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
/*6*/ -1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
/*7*/ 25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
/*8*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*9*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*a*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*b*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*c*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*d*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*e*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
/*f*/ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
};
unsigned long
ruby_scan_digits(const char *str, ssize_t len, int base, size_t *retlen, int *overflow)
{
const char *start = str;
unsigned long ret = 0, x;
unsigned long mul_overflow = (~(unsigned long)0) / base;
*overflow = 0;
if (!len) {
*retlen = 0;
return 0;
}
do {
int d = ruby_digit36_to_number_table[(unsigned char)*str++];
if (d == -1 || base <= d) {
--str;
break;
}
if (mul_overflow < ret)
*overflow = 1;
ret *= base;
x = ret;
ret += d;
if (ret < x)
*overflow = 1;
} while (len < 0 || --len);
*retlen = str - start;
return ret;
}
unsigned long
ruby_strtoul(const char *str, char **endptr, int base)
{
int c, b, overflow;
int sign = 0;
size_t len;
unsigned long ret;
const char *subject_found = str;
if (base == 1 || 36 < base) {
errno = EINVAL;
return 0;
}
while ((c = *str) && ISSPACE(c))
str++;
if (c == '+') {
sign = 1;
str++;
}
else if (c == '-') {
sign = -1;
str++;
}
if (str[0] == '0') {
subject_found = str+1;
if (base == 0 || base == 16) {
if (str[1] == 'x' || str[1] == 'X') {
b = 16;
str += 2;
}
else {
b = base == 0 ? 8 : 16;
str++;
}
}
else {
b = base;
str++;
}
}
else {
b = base == 0 ? 10 : base;
}
ret = ruby_scan_digits(str, -1, b, &len, &overflow);
if (0 < len)
subject_found = str+len;
if (endptr)
*endptr = (char*)subject_found;
if (overflow) {
errno = ERANGE;
return ULONG_MAX;
}
if (sign < 0) {
ret = (unsigned long)(-(long)ret);
return ret;
}
else {
return ret;
}
}
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#if defined(HAVE_FCNTL_H)
#include <fcntl.h>
#endif
#ifndef S_ISDIR
# define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif
#if !defined HAVE_BSD_QSORT_R && defined HAVE_QSORT_S
# define qsort_r(base, nel, size, arg, cmp) qsort_s(base, nel, size, cmp, arg)
# define cmp_bsd_qsort cmp_ms_qsort
# define HAVE_BSD_QSORT_R 1
#endif
#if defined HAVE_BSD_QSORT_R
typedef int (cmpfunc_t)(const void*, const void*, void*);
struct bsd_qsort_r_args {
cmpfunc_t *cmp;
void *arg;
};
static int
cmp_bsd_qsort(void *d, const void *a, const void *b)
{
const struct bsd_qsort_r_args *args = d;
return (*args->cmp)(a, b, args->arg);
}
void
ruby_qsort(void* base, const size_t nel, const size_t size, cmpfunc_t *cmp, void *d)
{
struct bsd_qsort_r_args args;
args.cmp = cmp;
args.arg = d;
qsort_r(base, nel, size, &args, cmp_bsd_qsort);
}
#elif !defined HAVE_GNU_QSORT_R
/* mm.c */
#define mmtype long
#define mmcount (16 / SIZEOF_LONG)
#define A ((mmtype*)a)
#define B ((mmtype*)b)
#define C ((mmtype*)c)
#define D ((mmtype*)d)
#define mmstep (sizeof(mmtype) * mmcount)
#define mmprepare(base, size) do {\
if (((VALUE)(base) % sizeof(mmtype)) == 0 && ((size) % sizeof(mmtype)) == 0) \
if ((size) >= mmstep) mmkind = 1;\
else mmkind = 0;\
else mmkind = -1;\
high = ((size) / mmstep) * mmstep;\
low = ((size) % mmstep);\
} while (0)\
#define mmarg mmkind, size, high, low
#define mmargdecl int mmkind, size_t size, size_t high, size_t low
static void mmswap_(register char *a, register char *b, mmargdecl)
{
if (a == b) return;
if (mmkind >= 0) {
register mmtype s;
#if mmcount > 1
if (mmkind > 0) {
register char *t = a + high;
do {
s = A[0]; A[0] = B[0]; B[0] = s;
s = A[1]; A[1] = B[1]; B[1] = s;
#if mmcount > 2
s = A[2]; A[2] = B[2]; B[2] = s;
#if mmcount > 3
s = A[3]; A[3] = B[3]; B[3] = s;
#endif
#endif
a += mmstep; b += mmstep;
} while (a < t);
}
#endif
if (low != 0) { s = A[0]; A[0] = B[0]; B[0] = s;
#if mmcount > 2
if (low >= 2 * sizeof(mmtype)) { s = A[1]; A[1] = B[1]; B[1] = s;
#if mmcount > 3
if (low >= 3 * sizeof(mmtype)) {s = A[2]; A[2] = B[2]; B[2] = s;}
#endif
}
#endif
}
}
else {
register char *t = a + size, s;
do {s = *a; *a++ = *b; *b++ = s;} while (a < t);
}
}
#define mmswap(a,b) mmswap_((a),(b),mmarg)
/* a, b, c = b, c, a */
static void mmrot3_(register char *a, register char *b, register char *c, mmargdecl)
{
if (mmkind >= 0) {
register mmtype s;
#if mmcount > 1
if (mmkind > 0) {
register char *t = a + high;
do {
s = A[0]; A[0] = B[0]; B[0] = C[0]; C[0] = s;
s = A[1]; A[1] = B[1]; B[1] = C[1]; C[1] = s;
#if mmcount > 2
s = A[2]; A[2] = B[2]; B[2] = C[2]; C[2] = s;
#if mmcount > 3
s = A[3]; A[3] = B[3]; B[3] = C[3]; C[3] = s;
#endif
#endif
a += mmstep; b += mmstep; c += mmstep;
} while (a < t);
}
#endif
if (low != 0) { s = A[0]; A[0] = B[0]; B[0] = C[0]; C[0] = s;
#if mmcount > 2
if (low >= 2 * sizeof(mmtype)) { s = A[1]; A[1] = B[1]; B[1] = C[1]; C[1] = s;
#if mmcount > 3
if (low == 3 * sizeof(mmtype)) {s = A[2]; A[2] = B[2]; B[2] = C[2]; C[2] = s;}
#endif
}
#endif
}
}
else {
register char *t = a + size, s;
do {s = *a; *a++ = *b; *b++ = *c; *c++ = s;} while (a < t);
}
}
#define mmrot3(a,b,c) mmrot3_((a),(b),(c),mmarg)
/* qs6.c */
/*****************************************************/
/* */
/* qs6 (Quick sort function) */
/* */
/* by Tomoyuki Kawamura 1995.4.21 */
/* kawamura@tokuyama.ac.jp */
/*****************************************************/
typedef struct { char *LL, *RR; } stack_node; /* Stack structure for L,l,R,r */
#define PUSH(ll,rr) do { top->LL = (ll); top->RR = (rr); ++top; } while (0) /* Push L,l,R,r */
#define POP(ll,rr) do { --top; (ll) = top->LL; (rr) = top->RR; } while (0) /* Pop L,l,R,r */
#define med3(a,b,c) ((*cmp)((a),(b),d)<0 ? \
((*cmp)((b),(c),d)<0 ? (b) : ((*cmp)((a),(c),d)<0 ? (c) : (a))) : \
((*cmp)((b),(c),d)>0 ? (b) : ((*cmp)((a),(c),d)<0 ? (a) : (c))))
typedef int (cmpfunc_t)(const void*, const void*, void*);
void
ruby_qsort(void* base, const size_t nel, const size_t size, cmpfunc_t *cmp, void *d)
{
register char *l, *r, *m; /* l,r:left,right group m:median point */
register int t, eq_l, eq_r; /* eq_l: all items in left group are equal to S */
char *L = base; /* left end of current region */
char *R = (char*)base + size*(nel-1); /* right end of current region */
size_t chklim = 63; /* threshold of ordering element check */
enum {size_bits = sizeof(size) * CHAR_BIT};
stack_node stack[size_bits]; /* enough for size_t size */
stack_node *top = stack;
int mmkind;
size_t high, low, n;
if (nel <= 1) return; /* need not to sort */
mmprepare(base, size);
goto start;
nxt:
if (stack == top) return; /* return if stack is empty */
POP(L,R);
for (;;) {
start:
if (L + size == R) { /* 2 elements */
if ((*cmp)(L,R,d) > 0) mmswap(L,R); goto nxt;
}
l = L; r = R;
n = (r - l + size) / size; /* number of elements */
m = l + size * (n >> 1); /* calculate median value */
if (n >= 60) {
register char *m1;
register char *m3;
if (n >= 200) {
n = size*(n>>3); /* number of bytes in splitting 8 */
{
register char *p1 = l + n;
register char *p2 = p1 + n;
register char *p3 = p2 + n;
m1 = med3(p1, p2, p3);
p1 = m + n;
p2 = p1 + n;
p3 = p2 + n;
m3 = med3(p1, p2, p3);
}
}
else {
n = size*(n>>2); /* number of bytes in splitting 4 */
m1 = l + n;
m3 = m + n;
}
m = med3(m1, m, m3);
}
if ((t = (*cmp)(l,m,d)) < 0) { /*3-5-?*/
if ((t = (*cmp)(m,r,d)) < 0) { /*3-5-7*/
if (chklim && nel >= chklim) { /* check if already ascending order */
char *p;
chklim = 0;
for (p=l; p<r; p+=size) if ((*cmp)(p,p+size,d) > 0) goto fail;
goto nxt;
}
fail: goto loopA; /*3-5-7*/
}
if (t > 0) {
if ((*cmp)(l,r,d) <= 0) {mmswap(m,r); goto loopA;} /*3-5-4*/
mmrot3(r,m,l); goto loopA; /*3-5-2*/
}
goto loopB; /*3-5-5*/
}
if (t > 0) { /*7-5-?*/
if ((t = (*cmp)(m,r,d)) > 0) { /*7-5-3*/
if (chklim && nel >= chklim) { /* check if already ascending order */
char *p;
chklim = 0;
for (p=l; p<r; p+=size) if ((*cmp)(p,p+size,d) < 0) goto fail2;
while (l<r) {mmswap(l,r); l+=size; r-=size;} /* reverse region */
goto nxt;
}
fail2: mmswap(l,r); goto loopA; /*7-5-3*/
}
if (t < 0) {
if ((*cmp)(l,r,d) <= 0) {mmswap(l,m); goto loopB;} /*7-5-8*/
mmrot3(l,m,r); goto loopA; /*7-5-6*/
}
mmswap(l,r); goto loopA; /*7-5-5*/
}
if ((t = (*cmp)(m,r,d)) < 0) {goto loopA;} /*5-5-7*/
if (t > 0) {mmswap(l,r); goto loopB;} /*5-5-3*/
/* determining splitting type in case 5-5-5 */ /*5-5-5*/
for (;;) {
if ((l += size) == r) goto nxt; /*5-5-5*/
if (l == m) continue;
if ((t = (*cmp)(l,m,d)) > 0) {mmswap(l,r); l = L; goto loopA;}/*575-5*/
if (t < 0) {mmswap(L,l); l = L; goto loopB;} /*535-5*/
}
loopA: eq_l = 1; eq_r = 1; /* splitting type A */ /* left <= median < right */
for (;;) {
for (;;) {
if ((l += size) == r)
{l -= size; if (l != m) mmswap(m,l); l -= size; goto fin;}
if (l == m) continue;
if ((t = (*cmp)(l,m,d)) > 0) {eq_r = 0; break;}
if (t < 0) eq_l = 0;
}
for (;;) {
if (l == (r -= size))
{l -= size; if (l != m) mmswap(m,l); l -= size; goto fin;}
if (r == m) {m = l; break;}
if ((t = (*cmp)(r,m,d)) < 0) {eq_l = 0; break;}
if (t == 0) break;
}
mmswap(l,r); /* swap left and right */
}
loopB: eq_l = 1; eq_r = 1; /* splitting type B */ /* left < median <= right */
for (;;) {
for (;;) {
if (l == (r -= size))
{r += size; if (r != m) mmswap(r,m); r += size; goto fin;}
if (r == m) continue;
if ((t = (*cmp)(r,m,d)) < 0) {eq_l = 0; break;}
if (t > 0) eq_r = 0;
}
for (;;) {
if ((l += size) == r)
{r += size; if (r != m) mmswap(r,m); r += size; goto fin;}
if (l == m) {m = r; break;}
if ((t = (*cmp)(l,m,d)) > 0) {eq_r = 0; break;}
if (t == 0) break;
}
mmswap(l,r); /* swap left and right */
}
fin:
if (eq_l == 0) /* need to sort left side */
if (eq_r == 0) /* need to sort right side */
if (l-L < R-r) {PUSH(r,R); R = l;} /* sort left side first */
else {PUSH(L,l); L = r;} /* sort right side first */
else R = l; /* need to sort left side only */
else if (eq_r == 0) L = r; /* need to sort right side only */
else goto nxt; /* need not to sort both sides */
}
}
#endif /* HAVE_GNU_QSORT_R */
char *
ruby_strdup(const char *str)
{
char *tmp;
size_t len = strlen(str) + 1;
tmp = xmalloc(len);
memcpy(tmp, str, len);
return tmp;
}
char *
ruby_getcwd(void)
{
#if defined HAVE_GETCWD
# undef RUBY_UNTYPED_DATA_WARNING
# define RUBY_UNTYPED_DATA_WARNING 0
# if defined NO_GETCWD_MALLOC
VALUE guard = Data_Wrap_Struct((VALUE)0, NULL, RUBY_DEFAULT_FREE, NULL);
int size = 200;
char *buf = xmalloc(size);
while (!getcwd(buf, size)) {
int e = errno;
if (e != ERANGE) {
xfree(buf);
DATA_PTR(guard) = NULL;
rb_syserr_fail(e, "getcwd");
}
size *= 2;
DATA_PTR(guard) = buf;
buf = xrealloc(buf, size);
}
# else
VALUE guard = Data_Wrap_Struct((VALUE)0, NULL, free, NULL);
char *buf, *cwd = getcwd(NULL, 0);
DATA_PTR(guard) = cwd;
if (!cwd) rb_sys_fail("getcwd");
buf = ruby_strdup(cwd); /* allocate by xmalloc */
free(cwd);
# endif
DATA_PTR(RB_GC_GUARD(guard)) = NULL;
#else
# ifndef PATH_MAX
# define PATH_MAX 8192
# endif
char *buf = xmalloc(PATH_MAX+1);
if (!getwd(buf)) {
int e = errno;
xfree(buf);
rb_syserr_fail(e, "getwd");
}
#endif
return buf;
}
/****************************************************************
*
* The author of this software is David M. Gay.
*
* Copyright (c) 1991, 2000, 2001 by Lucent Technologies.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose without fee is hereby granted, provided that this entire notice
* is included in all copies of any software which is or includes a copy
* or modification of this software and in all copies of the supporting
* documentation for such software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR LUCENT MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
* OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
*
***************************************************************/
/* Please send bug reports to David M. Gay (dmg at acm dot org,
* with " at " changed at "@" and " dot " changed to "."). */
/* On a machine with IEEE extended-precision registers, it is
* necessary to specify double-precision (53-bit) rounding precision
* before invoking strtod or dtoa. If the machine uses (the equivalent
* of) Intel 80x87 arithmetic, the call
* _control87(PC_53, MCW_PC);
* does this with many compilers. Whether this or another call is
* appropriate depends on the compiler; for this to work, it may be
* necessary to #include "float.h" or another system-dependent header
* file.
*/
/* strtod for IEEE-, VAX-, and IBM-arithmetic machines.
*
* This strtod returns a nearest machine number to the input decimal
* string (or sets errno to ERANGE). With IEEE arithmetic, ties are
* broken by the IEEE round-even rule. Otherwise ties are broken by
* biased rounding (add half and chop).
*
* Inspired loosely by William D. Clinger's paper "How to Read Floating
* Point Numbers Accurately" [Proc. ACM SIGPLAN '90, pp. 92-101].
*
* Modifications:
*
* 1. We only require IEEE, IBM, or VAX double-precision
* arithmetic (not IEEE double-extended).
* 2. We get by with floating-point arithmetic in a case that
* Clinger missed -- when we're computing d * 10^n
* for a small integer d and the integer n is not too
* much larger than 22 (the maximum integer k for which
* we can represent 10^k exactly), we may be able to
* compute (d*10^k) * 10^(e-k) with just one roundoff.
* 3. Rather than a bit-at-a-time adjustment of the binary
* result in the hard case, we use floating-point
* arithmetic to determine the adjustment to within
* one bit; only in really hard cases do we need to
* compute a second residual.
* 4. Because of 3., we don't need a large table of powers of 10
* for ten-to-e (just some small tables, e.g. of 10^k
* for 0 <= k <= 22).
*/
/*
* #define IEEE_LITTLE_ENDIAN for IEEE-arithmetic machines where the least
* significant byte has the lowest address.
* #define IEEE_BIG_ENDIAN for IEEE-arithmetic machines where the most
* significant byte has the lowest address.
* #define Long int on machines with 32-bit ints and 64-bit longs.
* #define IBM for IBM mainframe-style floating-point arithmetic.
* #define VAX for VAX-style floating-point arithmetic (D_floating).
* #define No_leftright to omit left-right logic in fast floating-point
* computation of dtoa.
* #define Honor_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
* and strtod and dtoa should round accordingly.
* #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
* and Honor_FLT_ROUNDS is not #defined.
* #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines
* that use extended-precision instructions to compute rounded
* products and quotients) with IBM.
* #define ROUND_BIASED for IEEE-format with biased rounding.
* #define Inaccurate_Divide for IEEE-format with correctly rounded
* products but inaccurate quotients, e.g., for Intel i860.
* #define NO_LONG_LONG on machines that do not have a "long long"
* integer type (of >= 64 bits). On such machines, you can
* #define Just_16 to store 16 bits per 32-bit Long when doing
* high-precision integer arithmetic. Whether this speeds things
* up or slows things down depends on the machine and the number
* being converted. If long long is available and the name is
* something other than "long long", #define Llong to be the name,
* and if "unsigned Llong" does not work as an unsigned version of
* Llong, #define #ULLong to be the corresponding unsigned type.
* #define KR_headers for old-style C function headers.
* #define Bad_float_h if your system lacks a float.h or if it does not
* define some or all of DBL_DIG, DBL_MAX_10_EXP, DBL_MAX_EXP,
* FLT_RADIX, FLT_ROUNDS, and DBL_MAX.
* #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n)
* if memory is available and otherwise does something you deem
* appropriate. If MALLOC is undefined, malloc will be invoked
* directly -- and assumed always to succeed.
* #define Omit_Private_Memory to omit logic (added Jan. 1998) for making
* memory allocations from a private pool of memory when possible.
* When used, the private pool is PRIVATE_MEM bytes long: 2304 bytes,
* unless #defined to be a different length. This default length
* suffices to get rid of MALLOC calls except for unusual cases,
* such as decimal-to-binary conversion of a very long string of
* digits. The longest string dtoa can return is about 751 bytes
* long. For conversions by strtod of strings of 800 digits and
* all dtoa conversions in single-threaded executions with 8-byte
* pointers, PRIVATE_MEM >= 7400 appears to suffice; with 4-byte
* pointers, PRIVATE_MEM >= 7112 appears adequate.
* #define INFNAN_CHECK on IEEE systems to cause strtod to check for
* Infinity and NaN (case insensitively). On some systems (e.g.,
* some HP systems), it may be necessary to #define NAN_WORD0
* appropriately -- to the most significant word of a quiet NaN.
* (On HP Series 700/800 machines, -DNAN_WORD0=0x7ff40000 works.)
* When INFNAN_CHECK is #defined and No_Hex_NaN is not #defined,
* strtod also accepts (case insensitively) strings of the form
* NaN(x), where x is a string of hexadecimal digits and spaces;
* if there is only one string of hexadecimal digits, it is taken
* for the 52 fraction bits of the resulting NaN; if there are two
* or more strings of hex digits, the first is for the high 20 bits,
* the second and subsequent for the low 32 bits, with intervening
* white space ignored; but if this results in none of the 52
* fraction bits being on (an IEEE Infinity symbol), then NAN_WORD0
* and NAN_WORD1 are used instead.
* #define MULTIPLE_THREADS if the system offers preemptively scheduled
* multiple threads. In this case, you must provide (or suitably
* #define) two locks, acquired by ACQUIRE_DTOA_LOCK(n) and freed
* by FREE_DTOA_LOCK(n) for n = 0 or 1. (The second lock, accessed
* in pow5mult, ensures lazy evaluation of only one copy of high
* powers of 5; omitting this lock would introduce a small
* probability of wasting memory, but would otherwise be harmless.)
* You must also invoke freedtoa(s) to free the value s returned by
* dtoa. You may do so whether or not MULTIPLE_THREADS is #defined.
* #define NO_IEEE_Scale to disable new (Feb. 1997) logic in strtod that
* avoids underflows on inputs whose result does not underflow.
* If you #define NO_IEEE_Scale on a machine that uses IEEE-format
* floating-point numbers and flushes underflows to zero rather
* than implementing gradual underflow, then you must also #define
* Sudden_Underflow.
* #define YES_ALIAS to permit aliasing certain double values with
* arrays of ULongs. This leads to slightly better code with
* some compilers and was always used prior to 19990916, but it
* is not strictly legal and can cause trouble with aggressively
* optimizing compilers (e.g., gcc 2.95.1 under -O2).
* #define USE_LOCALE to use the current locale's decimal_point value.
* #define SET_INEXACT if IEEE arithmetic is being used and extra
* computation should be done to set the inexact flag when the
* result is inexact and avoid setting inexact when the result
* is exact. In this case, dtoa.c must be compiled in
* an environment, perhaps provided by #include "dtoa.c" in a
* suitable wrapper, that defines two functions,
* int get_inexact(void);
* void clear_inexact(void);
* such that get_inexact() returns a nonzero value if the
* inexact bit is already set, and clear_inexact() sets the
* inexact bit to 0. When SET_INEXACT is #defined, strtod
* also does extra computations to set the underflow and overflow
* flags when appropriate (i.e., when the result is tiny and
* inexact or when it is a numeric value rounded to +-infinity).
* #define NO_ERRNO if strtod should not assign errno = ERANGE when
* the result overflows to +-Infinity or underflows to 0.
*/
#ifdef WORDS_BIGENDIAN
#define IEEE_BIG_ENDIAN
#else
#define IEEE_LITTLE_ENDIAN
#endif
#ifdef __vax__
#define VAX
#undef IEEE_BIG_ENDIAN
#undef IEEE_LITTLE_ENDIAN
#endif
#if defined(__arm__) && !defined(__VFP_FP__)
#define IEEE_BIG_ENDIAN
#undef IEEE_LITTLE_ENDIAN
#endif
#undef Long
#undef ULong
#if SIZEOF_INT == 4
#define Long int
#define ULong unsigned int
#elif SIZEOF_LONG == 4
#define Long long int
#define ULong unsigned long int
#endif
#if HAVE_LONG_LONG
#define Llong LONG_LONG
#else
#define NO_LONG_LONG
#endif
#ifdef DEBUG
#include "stdio.h"
#define Bug(x) {fprintf(stderr, "%s\n", (x)); exit(EXIT_FAILURE);}
#endif
#include "stdlib.h"
#include "string.h"
#ifdef USE_LOCALE
#include "locale.h"
#endif
#ifdef MALLOC
extern void *MALLOC(size_t);
#else
#define MALLOC xmalloc
#endif
#ifdef FREE
extern void FREE(void*);
#else
#define FREE xfree
#endif
#ifndef Omit_Private_Memory
#ifndef PRIVATE_MEM
#define PRIVATE_MEM 2304
#endif
#define PRIVATE_mem ((PRIVATE_MEM+sizeof(double)-1)/sizeof(double))
static double private_mem[PRIVATE_mem], *pmem_next = private_mem;
#endif
#undef IEEE_Arith
#undef Avoid_Underflow
#ifdef IEEE_BIG_ENDIAN
#define IEEE_Arith
#endif
#ifdef IEEE_LITTLE_ENDIAN
#define IEEE_Arith
#endif
#ifdef Bad_float_h
#ifdef IEEE_Arith
#define DBL_DIG 15
#define DBL_MAX_10_EXP 308
#define DBL_MAX_EXP 1024
#define FLT_RADIX 2
#endif /*IEEE_Arith*/
#ifdef IBM
#define DBL_DIG 16
#define DBL_MAX_10_EXP 75
#define DBL_MAX_EXP 63
#define FLT_RADIX 16
#define DBL_MAX 7.2370055773322621e+75
#endif
#ifdef VAX
#define DBL_DIG 16
#define DBL_MAX_10_EXP 38
#define DBL_MAX_EXP 127
#define FLT_RADIX 2
#define DBL_MAX 1.7014118346046923e+38
#endif
#ifndef LONG_MAX
#define LONG_MAX 2147483647
#endif
#else /* ifndef Bad_float_h */
#include "float.h"
#endif /* Bad_float_h */
#ifndef __MATH_H__
#include "math.h"
#endif
#ifdef __cplusplus
extern "C" {
#if 0
} /* satisfy cc-mode */
#endif
#endif
#if defined(IEEE_LITTLE_ENDIAN) + defined(IEEE_BIG_ENDIAN) + defined(VAX) + defined(IBM) != 1
Exactly one of IEEE_LITTLE_ENDIAN, IEEE_BIG_ENDIAN, VAX, or IBM should be defined.
#endif
typedef union { double d; ULong L[2]; } U;
#ifdef YES_ALIAS
typedef double double_u;
# define dval(x) (x)
# ifdef IEEE_LITTLE_ENDIAN
# define word0(x) (((ULong *)&(x))[1])
# define word1(x) (((ULong *)&(x))[0])
# else
# define word0(x) (((ULong *)&(x))[0])
# define word1(x) (((ULong *)&(x))[1])
# endif
#else
typedef U double_u;
# ifdef IEEE_LITTLE_ENDIAN
# define word0(x) ((x).L[1])
# define word1(x) ((x).L[0])
# else
# define word0(x) ((x).L[0])
# define word1(x) ((x).L[1])
# endif
# define dval(x) ((x).d)
#endif
/* The following definition of Storeinc is appropriate for MIPS processors.
* An alternative that might be better on some machines is
* #define Storeinc(a,b,c) (*a++ = b << 16 | c & 0xffff)
*/
#if defined(IEEE_LITTLE_ENDIAN) + defined(VAX) + defined(__arm__)
#define Storeinc(a,b,c) (((unsigned short *)(a))[1] = (unsigned short)(b), \
((unsigned short *)(a))[0] = (unsigned short)(c), (a)++)
#else
#define Storeinc(a,b,c) (((unsigned short *)(a))[0] = (unsigned short)(b), \
((unsigned short *)(a))[1] = (unsigned short)(c), (a)++)
#endif
/* #define P DBL_MANT_DIG */
/* Ten_pmax = floor(P*log(2)/log(5)) */
/* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */
/* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */
/* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */
#ifdef IEEE_Arith
#define Exp_shift 20
#define Exp_shift1 20
#define Exp_msk1 0x100000
#define Exp_msk11 0x100000
#define Exp_mask 0x7ff00000
#define P 53
#define Bias 1023
#define Emin (-1022)
#define Exp_1 0x3ff00000
#define Exp_11 0x3ff00000
#define Ebits 11
#define Frac_mask 0xfffff
#define Frac_mask1 0xfffff
#define Ten_pmax 22
#define Bletch 0x10
#define Bndry_mask 0xfffff
#define Bndry_mask1 0xfffff
#define LSB 1
#define Sign_bit 0x80000000
#define Log2P 1
#define Tiny0 0
#define Tiny1 1
#define Quick_max 14
#define Int_max 14
#ifndef NO_IEEE_Scale
#define Avoid_Underflow
#ifdef Flush_Denorm /* debugging option */
#undef Sudden_Underflow
#endif
#endif
#ifndef Flt_Rounds
#ifdef FLT_ROUNDS
#define Flt_Rounds FLT_ROUNDS
#else
#define Flt_Rounds 1
#endif
#endif /*Flt_Rounds*/
#ifdef Honor_FLT_ROUNDS
#define Rounding rounding
#undef Check_FLT_ROUNDS
#define Check_FLT_ROUNDS
#else
#define Rounding Flt_Rounds
#endif
#else /* ifndef IEEE_Arith */
#undef Check_FLT_ROUNDS
#undef Honor_FLT_ROUNDS
#undef SET_INEXACT
#undef Sudden_Underflow
#define Sudden_Underflow
#ifdef IBM
#undef Flt_Rounds
#define Flt_Rounds 0
#define Exp_shift 24
#define Exp_shift1 24
#define Exp_msk1 0x1000000
#define Exp_msk11 0x1000000
#define Exp_mask 0x7f000000
#define P 14
#define Bias 65
#define Exp_1 0x41000000
#define Exp_11 0x41000000
#define Ebits 8 /* exponent has 7 bits, but 8 is the right value in b2d */
#define Frac_mask 0xffffff
#define Frac_mask1 0xffffff
#define Bletch 4
#define Ten_pmax 22
#define Bndry_mask 0xefffff
#define Bndry_mask1 0xffffff
#define LSB 1
#define Sign_bit 0x80000000
#define Log2P 4
#define Tiny0 0x100000
#define Tiny1 0
#define Quick_max 14
#define Int_max 15
#else /* VAX */
#undef Flt_Rounds
#define Flt_Rounds 1
#define Exp_shift 23
#define Exp_shift1 7
#define Exp_msk1 0x80
#define Exp_msk11 0x800000
#define Exp_mask 0x7f80
#define P 56
#define Bias 129
#define Exp_1 0x40800000
#define Exp_11 0x4080
#define Ebits 8
#define Frac_mask 0x7fffff
#define Frac_mask1 0xffff007f
#define Ten_pmax 24
#define Bletch 2
#define Bndry_mask 0xffff007f
#define Bndry_mask1 0xffff007f
#define LSB 0x10000
#define Sign_bit 0x8000
#define Log2P 1
#define Tiny0 0x80
#define Tiny1 0
#define Quick_max 15
#define Int_max 15
#endif /* IBM, VAX */
#endif /* IEEE_Arith */
#ifndef IEEE_Arith
#define ROUND_BIASED
#endif
#ifdef RND_PRODQUOT
#define rounded_product(a,b) ((a) = rnd_prod((a), (b)))
#define rounded_quotient(a,b) ((a) = rnd_quot((a), (b)))
extern double rnd_prod(double, double), rnd_quot(double, double);
#else
#define rounded_product(a,b) ((a) *= (b))