third-party-mirror / GRTEv5 / refs/heads/master / . / google3 / third_party / grte / v5_src / glibc-2.27 / wcsmbs / wcsncmp.c

/* Copyright (C) 1995-2018 Free Software Foundation, Inc. | |

This file is part of the GNU C Library. | |

Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. | |

The GNU C Library is free software; you can redistribute it and/or | |

modify it under the terms of the GNU Lesser General Public | |

License as published by the Free Software Foundation; either | |

version 2.1 of the License, or (at your option) any later version. | |

The GNU C 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 | |

Lesser General Public License for more details. | |

You should have received a copy of the GNU Lesser General Public | |

License along with the GNU C Library; if not, see | |

<http://www.gnu.org/licenses/>. */ | |

#include <wchar.h> | |

#ifndef WCSNCMP | |

# define WCSNCMP wcsncmp | |

#endif | |

/* Compare no more than N characters of S1 and S2, | |

returning less than, equal to or greater than zero | |

if S1 is lexicographically less than, equal to or | |

greater than S2. */ | |

int | |

WCSNCMP (const wchar_t *s1, const wchar_t *s2, size_t n) | |

{ | |

wchar_t c1 = L'\0'; | |

wchar_t c2 = L'\0'; | |

if (n >= 4) | |

{ | |

size_t n4 = n >> 2; | |

do | |

{ | |

c1 = *s1++; | |

c2 = *s2++; | |

if (c1 == L'\0' || c1 != c2) | |

return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0); | |

c1 = *s1++; | |

c2 = *s2++; | |

if (c1 == L'\0' || c1 != c2) | |

return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0); | |

c1 = *s1++; | |

c2 = *s2++; | |

if (c1 == L'\0' || c1 != c2) | |

return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0); | |

c1 = *s1++; | |

c2 = *s2++; | |

if (c1 == L'\0' || c1 != c2) | |

return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0); | |

} while (--n4 > 0); | |

n &= 3; | |

} | |

while (n > 0) | |

{ | |

c1 = *s1++; | |

c2 = *s2++; | |

if (c1 == L'\0' || c1 != c2) | |

return c1 > c2 ? 1 : (c1 < c2 ? -1 : 0); | |

n--; | |

} | |

return 0; | |

} |