adns_unix_calls.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

/*
* adns_unix_calls.c
* - Simple implementation of requiered UNIX system calls and
*   library functions.
*/
/*
*  This file is
*    Copyright (C) 2000, 2002 Jarle (jgaa) Aase <[e-mail]>
*
*  It is part of adns, which is
*    Copyright (C) 1997-2000 Ian Jackson <[e-mail]>
*    Copyright (C) 1999 Tony Finch <[e-mail]>
*  
*  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 2, 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, write to the Free Software Foundation,
*  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 
*/


#include "adns.h"

int adns_writev(SOCKET FileDescriptor, const struct iovec * iov, int iovCount)
{
	int total_len = 0;	
	int i = 0, r = 0;
	char *buf = NULL, *p = NULL;
	
	for(; i < iovCount; i++)
		total_len += iov[i].iov_len;
	
	p = buf = (char *)alloca( (size_t) total_len);
	
	for(; i < iovCount; i++)
	{
		memcpy(p, iov[i].iov_base, (size_t) iov[i].iov_len);
		p += iov[i].iov_len;
	}
	
	ADNS_CLEAR_ERRNO
	r = send(FileDescriptor, buf, total_len, 0);
	ADNS_CAPTURE_ERRNO;
	return r;
}

int adns_inet_aton(const char *cp, struct in_addr *inp)
{
	inp->s_addr = inet_addr(cp);
	return inp->s_addr != INADDR_ANY;
}

int adns_getpid()
{
	return GetCurrentProcessId();
}

/* ReactOS: Fixed gettimeofday implementation.  Was wrong by a factor of
 * 10 */
int gettimeofday(struct timeval *tv, struct timezone *tz)
{
    static __int64 Adjustment;
    __int64 Now = 0;
    
    
    if (!Adjustment)
    {
	SYSTEMTIME st = {1970,1,3,0,0,0,0};
	
	SystemTimeToFileTime(&st, ((LPFILETIME)(VOID *)&Adjustment));
    }
    
    if (tz)
    {
	return -1;
    }
    
    GetSystemTimeAsFileTime(((LPFILETIME)(VOID *)&Now));
    Now -= Adjustment;
    
    /* 100 ns
       .1  us
       10 * 1000000 */
    tv->tv_sec = (long)(Now / 10000000);
    tv->tv_usec = (long)((Now /     10) % 1000000);
    return 0;
}

/* Memory allocated in the DLL must be freed in the dll, so
   we provide memory manegement functions. */

#ifdef ADNS_DLL

#undef malloc
#undef realloc
#undef free

void *adns_malloc(const size_t bytes)
{
	return malloc(bytes);
}

void *adns_realloc(void *ptr, const size_t bytes)
{
	return realloc(ptr, bytes);
}

void adns_free(void *ptr)
{
	free(ptr);
}

#endif /* ADNS_DLL */