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/* Compare strings while treating digits characters numerically.
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Copyright (C) 1997, 2000, 2002, 2004, 2006 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Jean-François Bignolles <bignolle@ecoledoc.ibp.fr>, 1997.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1, or (at your option)
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License along
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with this program; if not, write to the Free Software Foundation,
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Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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/* states: S_N: normal, S_I: comparing integral part, S_F: comparing
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fractional parts, S_Z: idem but with leading Zeroes only */
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/* result_type: CMP: return diff; LEN: compare using len_diff/diff */
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/* ISDIGIT differs from isdigit, as follows:
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- Its arg may be any int or unsigned int; it need not be an unsigned char
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- It's typically faster.
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POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
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isdigit unless it's important to use the locale's definition
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of `digit' even when the host does not conform to POSIX. */
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#define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
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# define __strverscmp strverscmp
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/* Compare S1 and S2 as strings holding indices/version numbers,
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returning less than, equal to or greater than zero if S1 is less than,
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equal to or greater than S2 (for more info, see the texinfo doc).
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__strverscmp (const char *s1, const char *s2)
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const unsigned char *p1 = (const unsigned char *) s1;
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const unsigned char *p2 = (const unsigned char *) s2;
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/* Symbol(s) 0 [1-9] others (padding)
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Transition (10) 0 (01) d (00) x (11) - */
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static const unsigned int next_state[] =
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/* S_N */ S_N, S_I, S_Z, S_N,
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/* S_I */ S_N, S_I, S_I, S_I,
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/* S_F */ S_N, S_F, S_F, S_F,
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/* S_Z */ S_N, S_F, S_Z, S_Z
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static const int result_type[] =
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/* state x/x x/d x/0 x/- d/x d/d d/0 d/-
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0/x 0/d 0/0 0/- -/x -/d -/0 -/- */
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/* S_N */ CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
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CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
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/* S_I */ CMP, -1, -1, CMP, 1, LEN, LEN, CMP,
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1, LEN, LEN, CMP, CMP, CMP, CMP, CMP,
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/* S_F */ CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
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CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
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/* S_Z */ CMP, 1, 1, CMP, -1, CMP, CMP, CMP,
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/* Hint: '0' is a digit too. */
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state = S_N | ((c1 == '0') + (ISDIGIT (c1) != 0));
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while ((diff = c1 - c2) == 0 && c1 != '\0')
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state = next_state[state];
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state |= (c1 == '0') + (ISDIGIT (c1) != 0);
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state = result_type[state << 2 | ((c2 == '0') + (ISDIGIT (c2) != 0))];
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while (ISDIGIT (*p1++))
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if (!ISDIGIT (*p2++))
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return ISDIGIT (*p2) ? -1 : diff;
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weak_alias (__strverscmp, strverscmp)