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-rw-r--r--libc/stdlib/_strtod.c623
1 files changed, 623 insertions, 0 deletions
diff --git a/libc/stdlib/_strtod.c b/libc/stdlib/_strtod.c
new file mode 100644
index 000000000..c4447d9ea
--- /dev/null
+++ b/libc/stdlib/_strtod.c
@@ -0,0 +1,623 @@
+/*
+ * Copyright (C) 2000-2005 Manuel Novoa III
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* Notes:
+ *
+ * The primary objective of this implementation was minimal size and
+ * portablility, while providing robustness and resonable accuracy.
+ *
+ * This implementation depends on IEEE floating point behavior and expects
+ * to be able to generate +/- infinity as a result.
+ *
+ * There are a number of compile-time options below.
+ */
+
+/* July 27, 2003
+ *
+ * General cleanup and some minor size optimizations.
+ * Change implementation to support __strtofpmax() rather than strtod().
+ * Now all the strto{floating pt}() funcs are implemented in terms of
+ * of the internal __strtofpmax() function.
+ * Support "nan", "inf", and "infinity" strings (case-insensitive).
+ * Support hexadecimal floating point notation.
+ * Support wchar variants.
+ * Support xlocale variants.
+ *
+ * TODO:
+ *
+ * Consider accumulating blocks of digits in longs to save floating pt mults.
+ * This would likely be much better on anything that only supported floats
+ * where DECIMAL_DIG == 9. Actually, if floats have FLT_MAX_10_EXP == 38,
+ * we could calculate almost all the exponent multipliers (p_base) in
+ * long arithmetic as well.
+ */
+
+/**********************************************************************/
+/* OPTIONS */
+/**********************************************************************/
+
+/* Defined if we want to recognize "nan", "inf", and "infinity". (C99) */
+#define _STRTOD_NAN_INF_STRINGS 1
+
+/* Defined if we want support hexadecimal floating point notation. (C99) */
+/* Note! Now controlled by uClibc configuration. See below. */
+#define _STRTOD_HEXADECIMAL_FLOATS 1
+
+/* Defined if we want to scale with a O(log2(exp)) multiplications.
+ * This is generally a good thing to do unless you are really tight
+ * on space and do not expect to convert values of large magnitude. */
+
+#define _STRTOD_LOG_SCALING 1
+
+/* WARNING!!! WARNING!!! WARNING!!! WARNING!!! WARNING!!!
+ *
+ * Clearing any of the options below this point is not advised (or tested).
+ *
+ * WARNING!!! WARNING!!! WARNING!!! WARNING!!! WARNING!!! */
+
+/* Defined if we want strtod to set errno appropriately. */
+/* NOTE: Implies all options below. */
+#define _STRTOD_ERRNO 1
+
+/* Defined if we want support for the endptr arg. */
+/* Implied by _STRTOD_ERRNO. */
+#define _STRTOD_ENDPTR 1
+
+/* Defined if we want to prevent overflow in accumulating the exponent. */
+/* Implied by _STRTOD_ERRNO. */
+#define _STRTOD_RESTRICT_EXP 1
+
+/* Defined if we want to process mantissa digits more intelligently. */
+/* Implied by _STRTOD_ERRNO. */
+#define _STRTOD_RESTRICT_DIGITS 1
+
+/* Defined if we want to skip scaling 0 for the exponent. */
+/* Implied by _STRTOD_ERRNO. */
+#define _STRTOD_ZERO_CHECK 1
+
+/**********************************************************************/
+/* Don't change anything that follows. */
+/**********************************************************************/
+
+#ifdef _STRTOD_ERRNO
+#undef _STRTOD_ENDPTR
+#undef _STRTOD_RESTRICT_EXP
+#undef _STRTOD_RESTRICT_DIGITS
+#undef _STRTOD_ZERO_CHECK
+#define _STRTOD_ENDPTR 1
+#define _STRTOD_RESTRICT_EXP 1
+#define _STRTOD_RESTRICT_DIGITS 1
+#define _STRTOD_ZERO_CHECK 1
+#endif
+
+/**********************************************************************/
+
+#define _ISOC99_SOURCE 1
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <float.h>
+#include <bits/uClibc_fpmax.h>
+
+#include <locale.h>
+
+#ifdef __UCLIBC_HAS_WCHAR__
+
+#include <wchar.h>
+#include <wctype.h>
+#include <bits/uClibc_uwchar.h>
+libc_hidden_proto(iswspace)
+#endif
+
+#ifdef __UCLIBC_HAS_XLOCALE__
+#include <xlocale.h>
+libc_hidden_proto(iswspace_l)
+#endif /* __UCLIBC_HAS_XLOCALE__ */
+
+/* Handle _STRTOD_HEXADECIMAL_FLOATS via uClibc config now. */
+#undef _STRTOD_HEXADECIMAL_FLOATS
+#ifdef __UCLIBC_HAS_HEXADECIMAL_FLOATS__
+#define _STRTOD_HEXADECIMAL_FLOATS 1
+#endif /* __UCLIBC_HAS_HEXADECIMAL_FLOATS__ */
+
+/**********************************************************************/
+
+#undef _STRTOD_FPMAX
+
+#if FPMAX_TYPE == 3
+
+#define NEED_STRTOLD_WRAPPER
+#define NEED_STRTOD_WRAPPER
+#define NEED_STRTOF_WRAPPER
+
+#elif FPMAX_TYPE == 2
+
+#define NEED_STRTOD_WRAPPER
+#define NEED_STRTOF_WRAPPER
+
+#elif FPMAX_TYPE == 1
+
+#define NEED_STRTOF_WRAPPER
+
+#else
+
+#error unknown FPMAX_TYPE!
+
+#endif
+
+extern void __fp_range_check(__fpmax_t y, __fpmax_t x) attribute_hidden;
+
+/**********************************************************************/
+
+#ifdef _STRTOD_RESTRICT_DIGITS
+#define EXP_DENORM_ADJUST DECIMAL_DIG
+#define MAX_ALLOWED_EXP (DECIMAL_DIG + EXP_DENORM_ADJUST - FPMAX_MIN_10_EXP)
+
+#if MAX_ALLOWED_EXP > INT_MAX
+#error size assumption violated for MAX_ALLOWED_EXP
+#endif
+#else
+/* We want some excess if we're not restricting mantissa digits. */
+#define MAX_ALLOWED_EXP ((20 - FPMAX_MIN_10_EXP) * 2)
+#endif
+
+
+#if defined(_STRTOD_RESTRICT_DIGITS) || defined(_STRTOD_ENDPTR) || defined(_STRTOD_HEXADECIMAL_FLOATS)
+#undef _STRTOD_NEED_NUM_DIGITS
+#define _STRTOD_NEED_NUM_DIGITS 1
+#endif
+
+/**********************************************************************/
+#if defined(L___strtofpmax) || defined(L___strtofpmax_l) || defined(L___wcstofpmax) || defined(L___wcstofpmax_l)
+
+#ifdef __UCLIBC_HAS_XLOCALE__
+libc_hidden_proto(__ctype_b_loc)
+#else
+#ifdef __UCLIBC_HAS_LOCALE__
+libc_hidden_proto(__global_locale)
+#endif
+libc_hidden_proto(__ctype_b)
+libc_hidden_proto(__ctype_tolower)
+#endif
+
+#if defined(L___wcstofpmax) || defined(L___wcstofpmax_l)
+
+#define __strtofpmax __wcstofpmax
+#define __strtofpmax_l __wcstofpmax_l
+
+#define Wchar wchar_t
+#ifdef __UCLIBC_DO_XLOCALE
+#define ISSPACE(C) iswspace_l((C), locale_arg)
+#else
+#define ISSPACE(C) iswspace((C))
+#endif
+
+#else /* defined(L___wcstofpmax) || defined(L___wcstofpmax_l) */
+
+#define Wchar char
+#ifdef __UCLIBC_DO_XLOCALE
+#define ISSPACE(C) isspace_l((C), locale_arg)
+#else
+#define ISSPACE(C) isspace((C))
+#endif
+
+#endif /* defined(L___wcstofpmax) || defined(L___wcstofpmax_l) */
+
+
+#if defined(__UCLIBC_HAS_XLOCALE__) && !defined(__UCLIBC_DO_XLOCALE)
+
+__fpmax_t attribute_hidden __strtofpmax(const Wchar *str, Wchar **endptr, int exponent_power)
+{
+ return __strtofpmax_l(str, endptr, exponent_power, __UCLIBC_CURLOCALE);
+}
+
+#else /* defined(__UCLIBC_HAS_XLOCALE__) && !defined(__UCLIBC_DO_XLOCALE) */
+
+libc_hidden_proto(memcmp)
+
+__fpmax_t attribute_hidden __XL_NPP(__strtofpmax)(const Wchar *str, Wchar **endptr, int exponent_power
+ __LOCALE_PARAM )
+{
+ __fpmax_t number;
+ __fpmax_t p_base = 10; /* Adjusted to 16 in the hex case. */
+ Wchar *pos0;
+#ifdef _STRTOD_ENDPTR
+ Wchar *pos1;
+#endif
+ Wchar *pos = (Wchar *) str;
+ int exponent_temp;
+ int negative; /* A flag for the number, a multiplier for the exponent. */
+#ifdef _STRTOD_NEED_NUM_DIGITS
+ int num_digits;
+#endif
+#ifdef __UCLIBC_HAS_LOCALE__
+#if defined(L___wcstofpmax) || defined(L___wcstofpmax_l)
+ wchar_t decpt_wc = __LOCALE_PTR->decimal_point;
+#else
+ const char *decpt = __LOCALE_PTR->decimal_point;
+ int decpt_len = __LOCALE_PTR->decimal_point_len;
+#endif
+#endif
+
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ Wchar expchar = 'e';
+ Wchar *poshex = NULL;
+ __uint16_t is_mask = _ISdigit;
+#define EXPCHAR expchar
+#define IS_X_DIGIT(C) __isctype((C), is_mask)
+#else /* _STRTOD_HEXADECIMAL_FLOATS */
+#define EXPCHAR 'e'
+#define IS_X_DIGIT(C) isdigit((C))
+#endif /* _STRTOD_HEXADECIMAL_FLOATS */
+
+ while (ISSPACE(*pos)) { /* Skip leading whitespace. */
+ ++pos;
+ }
+
+ negative = 0;
+ switch(*pos) { /* Handle optional sign. */
+ case '-': negative = 1; /* Fall through to increment position. */
+ case '+': ++pos;
+ }
+
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ if ((*pos == '0') && (((pos[1])|0x20) == 'x')) {
+ poshex = ++pos; /* Save position of 'x' in case no digits */
+ ++pos; /* and advance past it. */
+ is_mask = _ISxdigit; /* Used by IS_X_DIGIT. */
+ expchar = 'p'; /* Adjust exponent char. */
+ p_base = 16; /* Adjust base multiplier. */
+ }
+#endif
+
+ number = 0.;
+#ifdef _STRTOD_NEED_NUM_DIGITS
+ num_digits = -1;
+#endif
+/* exponent_power = 0; */
+ pos0 = NULL;
+
+ LOOP:
+ while (IS_X_DIGIT(*pos)) { /* Process string of (hex) digits. */
+#ifdef _STRTOD_RESTRICT_DIGITS
+ if (num_digits < 0) { /* First time through? */
+ ++num_digits; /* We've now seen a digit. */
+ }
+ if (num_digits || (*pos != '0')) { /* Had/have nonzero. */
+ ++num_digits;
+ if (num_digits <= DECIMAL_DIG) { /* Is digit significant? */
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ number = number * p_base
+ + (isdigit(*pos)
+ ? (*pos - '0')
+ : (((*pos)|0x20) - ('a' - 10)));
+#else /* _STRTOD_HEXADECIMAL_FLOATS */
+ number = number * p_base + (*pos - '0');
+#endif /* _STRTOD_HEXADECIMAL_FLOATS */
+ }
+ }
+#else /* _STRTOD_RESTRICT_DIGITS */
+#ifdef _STRTOD_NEED_NUM_DIGITS
+ ++num_digits;
+#endif
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ number = number * p_base
+ + (isdigit(*pos)
+ ? (*pos - '0')
+ : (((*pos)|0x20) - ('a' - 10)));
+#else /* _STRTOD_HEXADECIMAL_FLOATS */
+ number = number * p_base + (*pos - '0');
+#endif /* _STRTOD_HEXADECIMAL_FLOATS */
+#endif /* _STRTOD_RESTRICT_DIGITS */
+ ++pos;
+ }
+
+#ifdef __UCLIBC_HAS_LOCALE__
+#if defined(L___wcstofpmax) || defined(L___wcstofpmax_l)
+ if (!pos0 && (*pos == decpt_wc)) { /* First decimal point? */
+ pos0 = ++pos;
+ goto LOOP;
+ }
+#else
+ if (!pos0 && !memcmp(pos, decpt, decpt_len)) { /* First decimal point? */
+ pos0 = (pos += decpt_len);
+ goto LOOP;
+ }
+#endif
+#else /* __UCLIBC_HAS_LOCALE__ */
+ if ((*pos == '.') && !pos0) { /* First decimal point? */
+ pos0 = ++pos; /* Save position of decimal point */
+ goto LOOP; /* and process rest of digits. */
+ }
+#endif /* __UCLIBC_HAS_LOCALE__ */
+
+#ifdef _STRTOD_NEED_NUM_DIGITS
+ if (num_digits<0) { /* Must have at least one digit. */
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ if (poshex) { /* Back up to '0' in '0x' prefix. */
+ pos = poshex;
+ goto DONE;
+ }
+#endif /* _STRTOD_HEXADECIMAL_FLOATS */
+
+#ifdef _STRTOD_NAN_INF_STRINGS
+ if (!pos0) { /* No decimal point, so check for inf/nan. */
+ /* Note: nan is the first string so 'number = i/0.;' works. */
+ static const char nan_inf_str[] = "\05nan\0\012infinity\0\05inf\0";
+ int i = 0;
+
+#ifdef __UCLIBC_HAS_LOCALE__
+ /* Avoid tolower problems for INFINITY in the tr_TR locale. (yuk)*/
+#undef _tolower
+#define _tolower(C) ((C)|0x20)
+#endif /* __UCLIBC_HAS_LOCALE__ */
+
+ do {
+ /* Unfortunately, we have no memcasecmp(). */
+ int j = 0;
+ while (_tolower(pos[j]) == nan_inf_str[i+1+j]) {
+ ++j;
+ if (!nan_inf_str[i+1+j]) {
+ number = i / 0.;
+ if (negative) { /* Correct for sign. */
+ number = -number;
+ }
+ pos += nan_inf_str[i] - 2;
+ goto DONE;
+ }
+ }
+ i += nan_inf_str[i];
+ } while (nan_inf_str[i]);
+ }
+
+#endif /* STRTOD_NAN_INF_STRINGS */
+#ifdef _STRTOD_ENDPTR
+ pos = (Wchar *) str;
+#endif
+ goto DONE;
+ }
+#endif /* _STRTOD_NEED_NUM_DIGITS */
+
+#ifdef _STRTOD_RESTRICT_DIGITS
+ if (num_digits > DECIMAL_DIG) { /* Adjust exponent for skipped digits. */
+ exponent_power += num_digits - DECIMAL_DIG;
+ }
+#endif
+
+ if (pos0) {
+ exponent_power += pos0 - pos; /* Adjust exponent for decimal point. */
+ }
+
+#ifdef _STRTOD_HEXADECIMAL_FLOATS
+ if (poshex) {
+ exponent_power *= 4; /* Above is 2**4, but below is 2. */
+ p_base = 2;
+ }
+#endif /* _STRTOD_HEXADECIMAL_FLOATS */
+
+ if (negative) { /* Correct for sign. */
+ number = -number;
+ }
+
+ /* process an exponent string */
+ if (((*pos)|0x20) == EXPCHAR) {
+#ifdef _STRTOD_ENDPTR
+ pos1 = pos;
+#endif
+ negative = 1;
+ switch(*++pos) { /* Handle optional sign. */
+ case '-': negative = -1; /* Fall through to increment pos. */
+ case '+': ++pos;
+ }
+
+ pos0 = pos;
+ exponent_temp = 0;
+ while (isdigit(*pos)) { /* Process string of digits. */
+#ifdef _STRTOD_RESTRICT_EXP
+ if (exponent_temp < MAX_ALLOWED_EXP) { /* Avoid overflow. */
+ exponent_temp = exponent_temp * 10 + (*pos - '0');
+ }
+#else
+ exponent_temp = exponent_temp * 10 + (*pos - '0');
+#endif
+ ++pos;
+ }
+
+#ifdef _STRTOD_ENDPTR
+ if (pos == pos0) { /* No digits? */
+ pos = pos1; /* Back up to {e|E}/{p|P}. */
+ } /* else */
+#endif
+
+ exponent_power += negative * exponent_temp;
+ }
+
+#ifdef _STRTOD_ZERO_CHECK
+ if (number == 0.) {
+ goto DONE;
+ }
+#endif
+
+ /* scale the result */
+#ifdef _STRTOD_LOG_SCALING
+ exponent_temp = exponent_power;
+
+ if (exponent_temp < 0) {
+ exponent_temp = -exponent_temp;
+ }
+
+ while (exponent_temp) {
+ if (exponent_temp & 1) {
+ if (exponent_power < 0) {
+ /* Warning... caluclating a factor for the exponent and
+ * then dividing could easily be faster. But doing so
+ * might cause problems when dealing with denormals. */
+ number /= p_base;
+ } else {
+ number *= p_base;
+ }
+ }
+ exponent_temp >>= 1;
+ p_base *= p_base;
+ }
+
+#else /* _STRTOD_LOG_SCALING */
+ while (exponent_power) {
+ if (exponent_power < 0) {
+ number /= p_base;
+ exponent_power++;
+ } else {
+ number *= p_base;
+ exponent_power--;
+ }
+ }
+#endif /* _STRTOD_LOG_SCALING */
+
+#ifdef _STRTOD_ERRNO
+ if (__FPMAX_ZERO_OR_INF_CHECK(number)) {
+ __set_errno(ERANGE);
+ }
+#endif
+
+ DONE:
+#ifdef _STRTOD_ENDPTR
+ if (endptr) {
+ *endptr = pos;
+ }
+#endif
+
+ return number;
+}
+
+#endif /* defined(__UCLIBC_HAS_XLOCALE__) && !defined(__UCLIBC_DO_XLOCALE) */
+
+#endif
+/**********************************************************************/
+#ifdef L___fp_range_check
+#if defined(NEED_STRTOF_WRAPPER) || defined(NEED_STRTOD_WRAPPER)
+
+void attribute_hidden __fp_range_check(__fpmax_t y, __fpmax_t x)
+{
+ if (__FPMAX_ZERO_OR_INF_CHECK(y) /* y is 0 or +/- infinity */
+ && (y != 0) /* y is not 0 (could have x>0, y==0 if underflow) */
+ && !__FPMAX_ZERO_OR_INF_CHECK(x) /* x is not 0 or +/- infinity */
+ ) {
+ __set_errno(ERANGE); /* Then x is not in y's range. */
+ }
+}
+
+#endif
+#endif
+/**********************************************************************/
+#if defined(L_strtof) || defined(L_strtof_l) || defined(L_wcstof) || defined(L_wcstof_l)
+#if defined(NEED_STRTOF_WRAPPER)
+
+#if defined(L_wcstof) || defined(L_wcstof_l)
+#define strtof wcstof
+#define strtof_l wcstof_l
+#define __strtofpmax __wcstofpmax
+#define __strtofpmax_l __wcstofpmax_l
+#define Wchar wchar_t
+#else
+#define Wchar char
+#endif
+
+
+libc_hidden_proto(__XL_NPP(strtof))
+float __XL_NPP(strtof)(const Wchar *str, Wchar **endptr __LOCALE_PARAM )
+{
+#if FPMAX_TYPE == 1
+ return __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+#else
+ __fpmax_t x;
+ float y;
+
+ x = __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+ y = (float) x;
+
+ __fp_range_check(y, x);
+
+ return y;
+#endif
+}
+libc_hidden_def(__XL_NPP(strtof))
+
+#endif
+#endif
+/**********************************************************************/
+#if defined(L_strtod) || defined(L_strtod_l) || defined(L_wcstod) || defined(L_wcstod_l)
+#if defined(NEED_STRTOD_WRAPPER)
+
+#if defined(L_wcstod) || defined(L_wcstod_l)
+#define strtod wcstod
+#define strtod_l wcstod_l
+#define __strtofpmax __wcstofpmax
+#define __strtofpmax_l __wcstofpmax_l
+#define Wchar wchar_t
+#else
+#define Wchar char
+#endif
+
+libc_hidden_proto(__XL_NPP(strtod))
+double __XL_NPP(strtod)(const Wchar *__restrict str,
+ Wchar **__restrict endptr __LOCALE_PARAM )
+{
+#if FPMAX_TYPE == 2
+ return __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+#else
+ __fpmax_t x;
+ double y;
+
+ x = __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+ y = (double) x;
+
+ __fp_range_check(y, x);
+
+ return y;
+#endif
+}
+libc_hidden_def(__XL_NPP(strtod))
+
+#endif
+#endif
+/**********************************************************************/
+#if defined(L_strtold) || defined(L_strtold_l) || defined(L_wcstold) || defined(L_wcstold_l)
+#if defined(NEED_STRTOLD_WRAPPER)
+
+#if defined(L_wcstold) || defined(L_wcstold_l)
+#define strtold wcstold
+#define strtold_l wcstold_l
+#define __strtofpmax __wcstofpmax
+#define __strtofpmax_l __wcstofpmax_l
+#define Wchar wchar_t
+#else
+#define Wchar char
+#endif
+
+libc_hidden_proto(__XL_NPP(strtold))
+long double __XL_NPP(strtold) (const Wchar *str, Wchar **endptr __LOCALE_PARAM )
+{
+#if FPMAX_TYPE == 3
+ return __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+#else
+ __fpmax_t x;
+ long double y;
+
+ x = __XL_NPP(__strtofpmax)(str, endptr, 0 __LOCALE_ARG );
+ y = (long double) x;
+
+ __fp_range_check(y, x);
+
+ return y;
+#endif
+}
+libc_hidden_def(__XL_NPP(strtold))
+
+#endif
+#endif
+/**********************************************************************/