asctime.c

上一个上传的有问题,这个是好的。visopsys包括系统内核和GUI的全部SOURCE code ,还包括一些基本的docs文档。里面src子目录对应所有SOURCE code.对于想研究操作系统的朋

// 
//  Visopsys
//  Copyright (C) 1998-2007 J. Andrew McLaughlin
//  
//  This 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.
//
//  This 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 this library; if not, write to the Free Software Foundation,
//  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
//  asctime.c
//

// This is the standard "asctime" function, as found in standard C libraries

#include <time.h>
#include <stdio.h>
#include <errno.h>


char *asctime(const struct tm *timePtr)
{
  // From the linux man page about this function:
  // The asctime() function converts the broken-down time value
  // timeptr into a string with the  same  format  as  ctime().
  // The  return  value points to a statically allocated string
  // which might be overwritten by subsequent calls to  any  of
  // the date and time functions.
  
  // ctime() time format:
  // "Wed Jun 30 21:49:08 1993\n"

  static char *weekDay[] = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"};
  static char *month[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
			   "Aug", "Sep", "Oct", "Nov", "Dec" };
  static char timeString[25];

  // Make sure timePtr is not NULL
  if (timePtr == NULL)
    {
      errno = ERR_NULLPARAMETER;
      return (NULL);
    }
  
  // Create the string
  sprintf(timeString, "%s %s %d %02d:%02d:%02d %d", weekDay[timePtr->tm_wday],
	  month[timePtr->tm_mon], timePtr->tm_mday, timePtr->tm_hour,
	  timePtr->tm_min, timePtr->tm_sec, timePtr->tm_year);

  // Ok, return a pointer to timeString
  return (timeString);
}