string-inlines.c

glibc 库, 不仅可以学习使用库函数,还可以学习函数的具体实现,是提高功力的好资料

/* Copyright (C) 1999, 2002, 2003 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/*  <bits/string.h> and <bits/string2.h> declare some extern inline
    functions.  These functions are declared additionally here if
    inlining is not possible.  */

#undef __USE_STRING_INLINES
#define __USE_STRING_INLINES
#define _FORCE_INLINES
#define __STRING_INLINE /* empty */
#define __NO_INLINE__

/* This is to avoid PLT entries for the x86 version.  */
#define __memcpy_g __memcpy_g_internal
#define __strchr_g __strchr_g_internal

#include <string.h>
#undef index
#undef rindex

#undef __NO_INLINE__
#include <bits/string.h>
#include <bits/string2.h>

void *
(__memcpy_c) (void *d, const void *s, size_t n)
{
  return memcpy (d, s, n);
}

void *
__memset_cc (void *s, unsigned long int pattern, size_t n)
{
  return memset (s, pattern & 0xff, n);
}
strong_alias (__memset_cc, __memset_cg)

void *
__memset_gg (void *s, char c, size_t n)
{
  return memset (s, c, n);
}

#ifdef __memcpy_c
# undef __memcpy_g
strong_alias (__memcpy_g_internal, __memcpy_g)
# undef __strchr_g
strong_alias (__strchr_g_internal, __strchr_g)
#endif