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-rw-r--r--mpf/set_str.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/mpf/set_str.c b/mpf/set_str.c
new file mode 100644
index 000000000..2ab9faebe
--- /dev/null
+++ b/mpf/set_str.c
@@ -0,0 +1,302 @@
+/* mpf_set_str (dest, string, base) -- Convert the string STRING
+ in base BASE to a float in dest. If BASE is zero, the leading characters
+ of STRING is used to figure out the base.
+
+Copyright (C) 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Library General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at your
+option) any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
+License for more details.
+
+You should have received a copy of the GNU Library General Public License
+along with the GNU MP Library; see the file COPYING.LIB. If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include <string.h>
+#include <ctype.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+
+long int strtol _PROTO ((const char *, char **ptr, int));
+
+static int
+digit_value_in_base (c, base)
+ int c;
+ int base;
+{
+ int digit;
+
+ if (isdigit (c))
+ digit = c - '0';
+ else if (islower (c))
+ digit = c - 'a' + 10;
+ else if (isupper (c))
+ digit = c - 'A' + 10;
+ else
+ return -1;
+
+ if (digit < base)
+ return digit;
+ return -1;
+}
+
+int
+#if __STDC__
+mpf_set_str (mpf_ptr x, const char *str, int base)
+#else
+mpf_set_str (x, str, base)
+ mpf_ptr x;
+ char *str;
+ int base;
+#endif
+{
+ size_t str_size;
+ char *s, *begs;
+ size_t i;
+ mp_size_t xsize;
+ int c;
+ int negative;
+ char *dotpos = 0;
+ int expflag;
+ int decimal_exponent_flag;
+ TMP_DECL (marker);
+
+ TMP_MARK (marker);
+
+ c = *str;
+
+ /* Skip whitespace. */
+ while (isspace (c))
+ c = *++str;
+
+ negative = 0;
+ if (c == '-')
+ {
+ negative = 1;
+ c = *++str;
+ }
+
+ decimal_exponent_flag = base < 0;
+ base = ABS (base);
+
+ if (digit_value_in_base (c, base == 0 ? 10 : base) < 0)
+ return -1; /* error if no digits */
+
+ /* If BASE is 0, try to find out the base by looking at the initial
+ characters. */
+ if (base == 0)
+ {
+ base = 10;
+#if 0
+ if (c == '0')
+ {
+ base = 8;
+ c = *++str;
+ if (c == 'x' || c == 'X')
+ base = 16;
+ }
+#endif
+ }
+
+ expflag = 0;
+ str_size = strlen (str);
+ for (i = 0; i < str_size; i++)
+ {
+ c = str[i];
+ if (c == '@' || (base <= 10 && (c == 'e' || c == 'E')))
+ {
+ expflag = 1;
+ str_size = i;
+ break;
+ }
+
+ }
+
+ s = begs = (char *) TMP_ALLOC (str_size + 1);
+
+ for (i = 0; i < str_size; i++)
+ {
+ c = *str;
+ if (!isspace (c))
+ {
+ int dig;
+
+ if (c == '.')
+ {
+ if (dotpos != 0)
+ {
+ TMP_FREE (marker);
+ return -1;
+ }
+ dotpos = s;
+ }
+ else
+ {
+ dig = digit_value_in_base (c, base);
+ if (dig < 0)
+ {
+ TMP_FREE (marker);
+ return -1;
+ }
+ *s++ = dig;
+ }
+ }
+ c = *++str;
+ }
+
+ str_size = s - begs;
+
+ xsize = str_size / __mp_bases[base].chars_per_limb + 2;
+ {
+ long exp_in_base;
+ mp_size_t rsize, msize;
+ int cnt, i;
+ mp_ptr mp, xp, tp, rp;
+ mp_limb_t cy;
+ mp_exp_t exp_in_limbs;
+ mp_size_t prec = x->_mp_prec;
+ int divflag;
+ mp_size_t xxx = 0;
+
+ mp = (mp_ptr) TMP_ALLOC (xsize * BYTES_PER_MP_LIMB);
+ msize = mpn_set_str (mp, (unsigned char *) begs, str_size, base);
+
+ if (msize == 0)
+ {
+ x->_mp_size = 0;
+ x->_mp_exp = 0;
+ TMP_FREE (marker);
+ return 0;
+ }
+
+ if (expflag != 0)
+ exp_in_base = strtol (str + 1, (char **) 0,
+ decimal_exponent_flag ? 10 : base);
+ else
+ exp_in_base = 0;
+ if (dotpos != 0)
+ exp_in_base -= s - dotpos;
+ divflag = exp_in_base < 0;
+ exp_in_base = ABS (exp_in_base);
+
+ if (exp_in_base == 0)
+ {
+ MPN_COPY (x->_mp_d, mp, msize);
+ x->_mp_size = negative ? -msize : msize;
+ x->_mp_exp = msize;
+ TMP_FREE (marker);
+ return 0;
+ }
+
+#if 1
+ rsize = (((mp_size_t) (exp_in_base / __mp_bases[base].chars_per_bit_exactly))
+ / BITS_PER_MP_LIMB + 3);
+#else
+ count_leading_zeros (cnt, (mp_limb_t) base);
+ rsize = exp_in_base - cnt * exp_in_base / BITS_PER_MP_LIMB + 1;
+#endif
+ rp = (mp_ptr) TMP_ALLOC (rsize * BYTES_PER_MP_LIMB);
+ tp = (mp_ptr) TMP_ALLOC (rsize * BYTES_PER_MP_LIMB);
+
+ rp[0] = base;
+ rsize = 1;
+
+ count_leading_zeros (cnt, exp_in_base);
+
+ for (i = BITS_PER_MP_LIMB - cnt - 2; i >= 0; i--)
+ {
+ mpn_mul_n (tp, rp, rp, rsize);
+ rsize = 2 * rsize;
+ rsize -= tp[rsize - 1] == 0;
+ xp = tp; tp = rp; rp = xp;
+
+ if (((exp_in_base >> i) & 1) != 0)
+ {
+ cy = mpn_mul_1 (rp, rp, rsize, (mp_limb_t) base);
+ rp[rsize] = cy;
+ rsize += cy != 0;
+ }
+ }
+
+ if (rsize > prec)
+ {
+ xxx += rsize - prec;
+ rp += rsize - prec;
+ rsize = prec;
+ }
+#if 0
+ if (msize > prec)
+ {
+ xxx -= msize - prec;
+ mp += msize - prec;
+ msize = prec;
+ }
+#endif
+ if (divflag)
+ {
+ mp_ptr qp;
+ mp_limb_t qflag;
+ mp_size_t xtra;
+ if (msize <= rsize)
+ {
+ /* Allocate extra limb for current divrem sematics. */
+ mp_ptr tmp = (mp_ptr) TMP_ALLOC ((rsize + 1) * BYTES_PER_MP_LIMB);
+ MPN_ZERO (tmp, rsize - msize);
+ MPN_COPY (tmp + rsize - msize, mp, msize);
+ mp = tmp;
+ xxx += rsize - msize;
+ msize = rsize;
+ }
+ count_leading_zeros (cnt, rp[rsize - 1]);
+ if (cnt != 0)
+ {
+ mpn_lshift (rp, rp, rsize, cnt);
+ cy = mpn_lshift (mp, mp, msize, cnt);
+ if (cy)
+ mp[msize++] = cy;
+ }
+ qp = (mp_ptr) TMP_ALLOC ((prec + 1) * BYTES_PER_MP_LIMB);
+ xtra = prec - (msize - rsize);
+ qflag = mpn_divrem (qp, xtra, mp, msize, rp, rsize);
+ qp[prec] = qflag;
+ tp = qp;
+ rsize = prec + qflag;
+ exp_in_limbs = rsize - xtra - xxx;
+ }
+ else
+ {
+ tp = (mp_ptr) TMP_ALLOC ((rsize + msize) * BYTES_PER_MP_LIMB);
+ if (rsize > msize)
+ mpn_mul (tp, rp, rsize, mp, msize);
+ else
+ mpn_mul (tp, mp, msize, rp, rsize);
+ rsize += msize;
+ rsize -= tp[rsize - 1] == 0;
+ exp_in_limbs = rsize + xxx;
+
+ if (rsize > prec)
+ {
+ xxx = rsize - prec;
+ tp += rsize - prec;
+ rsize = prec;
+ exp_in_limbs += 0;
+ }
+ }
+
+ MPN_COPY (x->_mp_d, tp, rsize);
+ x->_mp_size = negative ? -rsize : rsize;
+ x->_mp_exp = exp_in_limbs;
+ TMP_FREE (marker);
+ return 0;
+ }
+}
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