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/* Optimized string comparison.
Copyright (C) 2001-2002, 2007, 2009-2016 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>. */
#ifndef _GL_STREQ_H
#define _GL_STREQ_H
#include <string.h>
/* STREQ_OPT allows to optimize string comparison with a small literal string.
STREQ_OPT (s, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0)
is semantically equivalent to
strcmp (s, "EUC-KR") == 0
just faster. */
/* Help GCC to generate good code for string comparisons with
immediate strings. */
#if defined (__GNUC__) && defined (__OPTIMIZE__)
static inline int
streq9 (const char *s1, const char *s2)
{
return strcmp (s1 + 9, s2 + 9) == 0;
}
static inline int
streq8 (const char *s1, const char *s2, char s28)
{
if (s1[8] == s28)
{
if (s28 == 0)
return 1;
else
return streq9 (s1, s2);
}
else
return 0;
}
static inline int
streq7 (const char *s1, const char *s2, char s27, char s28)
{
if (s1[7] == s27)
{
if (s27 == 0)
return 1;
else
return streq8 (s1, s2, s28);
}
else
return 0;
}
static inline int
streq6 (const char *s1, const char *s2, char s26, char s27, char s28)
{
if (s1[6] == s26)
{
if (s26 == 0)
return 1;
else
return streq7 (s1, s2, s27, s28);
}
else
return 0;
}
static inline int
streq5 (const char *s1, const char *s2, char s25, char s26, char s27, char s28)
{
if (s1[5] == s25)
{
if (s25 == 0)
return 1;
else
return streq6 (s1, s2, s26, s27, s28);
}
else
return 0;
}
static inline int
streq4 (const char *s1, const char *s2, char s24, char s25, char s26, char s27, char s28)
{
if (s1[4] == s24)
{
if (s24 == 0)
return 1;
else
return streq5 (s1, s2, s25, s26, s27, s28);
}
else
return 0;
}
static inline int
streq3 (const char *s1, const char *s2, char s23, char s24, char s25, char s26, char s27, char s28)
{
if (s1[3] == s23)
{
if (s23 == 0)
return 1;
else
return streq4 (s1, s2, s24, s25, s26, s27, s28);
}
else
return 0;
}
static inline int
streq2 (const char *s1, const char *s2, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
{
if (s1[2] == s22)
{
if (s22 == 0)
return 1;
else
return streq3 (s1, s2, s23, s24, s25, s26, s27, s28);
}
else
return 0;
}
static inline int
streq1 (const char *s1, const char *s2, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
{
if (s1[1] == s21)
{
if (s21 == 0)
return 1;
else
return streq2 (s1, s2, s22, s23, s24, s25, s26, s27, s28);
}
else
return 0;
}
static inline int
streq0 (const char *s1, const char *s2, char s20, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
{
if (s1[0] == s20)
{
if (s20 == 0)
return 1;
else
return streq1 (s1, s2, s21, s22, s23, s24, s25, s26, s27, s28);
}
else
return 0;
}
#define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
streq0 (s1, s2, s20, s21, s22, s23, s24, s25, s26, s27, s28)
#else
#define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
(strcmp (s1, s2) == 0)
#endif
#endif /* _GL_STREQ_H */