/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   replacement routines for broken systems
   Copyright (C) Andrew Tridgell 1992-1998
   
   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 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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

extern int DEBUGLEVEL;


 void replace_dummy(void) 
{}


#ifndef HAVE_FTRUNCATE
 /*******************************************************************
ftruncate for operating systems that don't have it
********************************************************************/
 int ftruncate(int f,SMB_OFF_T l)
{
      struct  flock   fl;

      fl.l_whence = 0;
      fl.l_len = 0;
      fl.l_start = l;
      fl.l_type = F_WRLCK;
      return fcntl(f, F_FREESP, &fl);
}
#endif


#ifndef HAVE_MKTIME
/*******************************************************************
a mktime() replacement for those who don't have it - contributed by 
C.A. Lademann <cal@zls.com>
********************************************************************/
#define  MINUTE  60
#define  HOUR    60*MINUTE
#define  DAY             24*HOUR
#define  YEAR    365*DAY
 time_t mktime(struct tm *t)
{
  struct tm       *u;
  time_t  epoch = 0;
  int             mon [] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
  y, m, i;

  if(t->tm_year < 70)
    return((time_t)-1);

  epoch = (t->tm_year - 70) * YEAR + 
    (t->tm_year / 4 - 70 / 4 - t->tm_year / 100) * DAY;

  y = t->tm_year;
  m = 0;

  for(i = 0; i < t->tm_mon; i++) {
    epoch += mon [m] * DAY;
    if(m == 1 && y % 4 == 0 && (y % 100 != 0 || y % 400 == 0))
      epoch += DAY;
    
    if(++m > 11) {
      m = 0;
      y++;
    }
  }

  epoch += (t->tm_mday - 1) * DAY;
  epoch += t->tm_hour * HOUR + t->tm_min * MINUTE + t->tm_sec;
  
  if((u = localtime(&epoch)) != NULL) {
    t->tm_sec = u->tm_sec;
    t->tm_min = u->tm_min;
    t->tm_hour = u->tm_hour;
    t->tm_mday = u->tm_mday;
    t->tm_mon = u->tm_mon;
    t->tm_year = u->tm_year;
    t->tm_wday = u->tm_wday;
    t->tm_yday = u->tm_yday;
    t->tm_isdst = u->tm_isdst;
  }

  return(epoch);
}
#endif /* !HAVE_MKTIME */



#ifndef HAVE_RENAME
/* Rename a file. (from libiberty in GNU binutils)  */
 int rename(const char *zfrom, const char *zto)
{
  if (link (zfrom, zto) < 0)
    {
      if (errno != EEXIST)
	return -1;
      if (unlink (zto) < 0
	  || link (zfrom, zto) < 0)
	return -1;
    }
  return unlink (zfrom);
}
#endif


#ifndef HAVE_INNETGR
/*
 * Search for a match in a netgroup. This replaces it on broken systems.
 */
 int innetgr(char *group,char *host,char *user,char *dom)
{
	char *hst, *usr, *dm;
  
	setnetgrent(group);
	while (getnetgrent(&hst, &usr, &dm)) {
		if (((host == 0) || (hst == 0) || !strcmp(host, hst)) &&
		    ((user == 0) || (usr == 0) || !strcmp(user, usr)) &&
		    ((dom == 0) || (dm == 0) || !strcmp(dom, dm))) {
			endnetgrent();
			return (1);
		}
	}
	endnetgrent();
	return (0);
}
#endif



#ifndef HAVE_INITGROUPS
/****************************************************************************
 some systems don't have an initgroups call 
****************************************************************************/
 int initgroups(char *name,gid_t id)
{
#ifndef HAVE_SETGROUPS
	static int done;
	if (!done) {
		DEBUG(1,("WARNING: running without setgroups\n"));
		done=1;
	}
	/* yikes! no SETGROUPS or INITGROUPS? how can this work? */
	return(0);
#else
	gid_t  grouplst[NGROUPS_MAX];
	int    i,j;
	struct group *g;
	char   *gr;
	
	grouplst[0] = id;
	i = 1;
	while (i < NGROUPS_MAX && 
	       ((g = (struct group *)getgrent()) != (struct group *)NULL)) {
		if (g->gr_gid == id)
			continue;
		j = 0;
		gr = g->gr_mem[0];
		while (gr && (*gr != (char)NULL)) {
			if (strcmp(name,gr) == 0) {
				grouplst[i] = g->gr_gid;
				i++;
				gr = (char *)NULL;
				break;
			}
			gr = g->gr_mem[++j];
		}
	}
	endgrent();
	return(setgroups(i,grouplst));
#endif
}
#endif


#if (defined(SecureWare) && defined(SCO))
/* This is needed due to needing the nap() function but we don't want
   to include the Xenix libraries since that will break other things...
   BTW: system call # 0x0c28 is the same as calling nap() */
 long nap(long milliseconds) {
	 return syscall(0x0c28, milliseconds);
 }
#endif


#ifndef HAVE_MEMMOVE
/*******************************************************************
safely copies memory, ensuring no overlap problems.
this is only used if the machine does not have it's own memmove().
this is not the fastest algorithm in town, but it will do for our
needs.
********************************************************************/
 void *memmove(void *dest,const void *src,int size)
{
	unsigned long d,s;
	int i;
	if (dest==src || !size) return(dest);

	d = (unsigned long)dest;
	s = (unsigned long)src;

	if ((d >= (s+size)) || (s >= (d+size))) {
		/* no overlap */
		memcpy(dest,src,size);
		return(dest);
	}

	if (d < s) {
		/* we can forward copy */
		if (s-d >= sizeof(int) && 
		    !(s%sizeof(int)) && 
		    !(d%sizeof(int)) && 
		    !(size%sizeof(int))) {
			/* do it all as words */
			int *idest = (int *)dest;
			int *isrc = (int *)src;
			size /= sizeof(int);
			for (i=0;i<size;i++) idest[i] = isrc[i];
		} else {
			/* simplest */
			char *cdest = (char *)dest;
			char *csrc = (char *)src;
			for (i=0;i<size;i++) cdest[i] = csrc[i];
		}
	} else {
		/* must backward copy */
		if (d-s >= sizeof(int) && 
		    !(s%sizeof(int)) && 
		    !(d%sizeof(int)) && 
		    !(size%sizeof(int))) {
			/* do it all as words */
			int *idest = (int *)dest;
			int *isrc = (int *)src;
			size /= sizeof(int);
			for (i=size-1;i>=0;i--) idest[i] = isrc[i];
		} else {
			/* simplest */
			char *cdest = (char *)dest;
			char *csrc = (char *)src;
			for (i=size-1;i>=0;i--) cdest[i] = csrc[i];
		}      
	}
	return(dest);
}
#endif

#ifndef HAVE_STRDUP
/****************************************************************************
duplicate a string
****************************************************************************/
 char *strdup(const char *s)
{
	int len;
	char *ret;

	if (!s) return(NULL);

	len = strlen(s)+1;
	ret = (char *)malloc(len);
	if (!ret) return(NULL);
	memcpy(ret,s,len);
	return(ret);
}
#endif

#ifdef REPLACE_INET_NTOA
char *rep_inet_ntoa(struct in_addr ip)
{
	unsigned char *p = (unsigned char *)&ip.s_addr;
	static char buf[18];
#if WORDS_BIGENDIAN
	slprintf(buf, 17, "%d.%d.%d.%d", 
		 (int)p[0], (int)p[1], (int)p[2], (int)p[3]);
#else
	slprintf(buf, 17, "%d.%d.%d.%d", 
		 (int)p[3], (int)p[2], (int)p[1], (int)p[0]);
#endif
	return buf;
}
#endif


#ifndef HAVE_SETENV
/*****************************************************************
set an env variable - some systems don't have this
*****************************************************************/  
 int setenv(const char *name, const char *value, int overwrite)
{
	pstring s;

	if (!overwrite && getenv(name)) return 0;

	slprintf(s,sizeof(s)-1,"%s=%s", name, value);

	return putenv(s);
}

#endif