/* 
   Unix SMB/CIFS implementation.
   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"

 void replace_dummy(void);
 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 /* HAVE_FTRUNCATE */


#ifndef HAVE_STRLCPY
/* like strncpy but does not 0 fill the buffer and always null 
   terminates. bufsize is the size of the destination buffer */
 size_t strlcpy(char *d, const char *s, size_t bufsize)
{
	size_t len = strlen(s);
	size_t ret = len;
	if (bufsize <= 0) return 0;
	if (len >= bufsize) len = bufsize-1;
	memcpy(d, s, len);
	d[len] = 0;
	return ret;
}
#endif

#ifndef HAVE_STRLCAT
/* like strncat but does not 0 fill the buffer and always null 
   terminates. bufsize is the length of the buffer, which should
   be one more than the maximum resulting string length */
 size_t strlcat(char *d, const char *s, size_t bufsize)
{
	size_t len1 = strlen(d);
	size_t len2 = strlen(s);
	size_t ret = len1 + len2;

	if (len1+len2 >= bufsize) {
		len2 = bufsize - (len1+1);
	}
	if (len2 > 0) {
		memcpy(d+len1, s, len2);
		d[len1+len2] = 0;
	}
	return ret;
}
#endif

#ifndef HAVE_MKTIME
/*******************************************************************
a mktime() replacement for those who don't have it - contributed by 
C.A. Lademann <cal@zls.com>
Corrections by richard.kettlewell@kewill.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 n;
  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);

  n = t->tm_year + 1900 - 1;
  epoch = (t->tm_year - 70) * YEAR + 
    ((n / 4 - n / 100 + n / 400) - (1969 / 4 - 1969 / 100 + 1969 / 400)) * DAY;

  y = t->tm_year + 1900;
  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 /* HAVE_RENAME */


#ifndef HAVE_INNETGR
#if defined(HAVE_SETNETGRENT) && defined(HAVE_GETNETGRENT) && defined(HAVE_ENDNETGRENT)
/*
 * Search for a match in a netgroup. This replaces it on broken systems.
 */
 int innetgr(const char *group,const char *host,const char *user,const 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 /* HAVE_SETNETGRENT HAVE_GETNETGRENT HAVE_ENDNETGRENT */
#endif /* HAVE_INNETGR */



#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 /* HAVE_SETGROUPS */
	gid_t *grouplst = NULL;
	int max_gr = groups_max();
	int ret;
	int    i,j;
	struct group *g;
	char   *gr;
	
	if((grouplst = (gid_t *)malloc(sizeof(gid_t) * max_gr)) == NULL) {
		DEBUG(0,("initgroups: malloc fail !\n"));
		return -1;
	}

	grouplst[0] = id;
	i = 1;
	while (i < max_gr && ((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();
	ret = sys_setgroups(i,grouplst);
	SAFE_FREE(grouplst);
	return ret;
#endif /* HAVE_SETGROUPS */
}
#endif /* HAVE_INITGROUPS */


#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 /* HAVE_MEMMOVE */

#ifndef HAVE_STRDUP
/****************************************************************************
duplicate a string
****************************************************************************/
 char *strdup(const char *s)
{
	size_t 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 /* HAVE_STRDUP */

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

#ifndef HAVE_STRTOUL
#ifndef ULONG_MAX
#define	ULONG_MAX	((unsigned long)(~0L))		/* 0xFFFFFFFF */
#endif

/*
 * Convert a string to an unsigned long integer.
 * Taken from libg++ - libiberty code.
 *
 * Ignores `locale' stuff.  Assumes that the upper and lower case
 * alphabets and digits are each contiguous.
 */
 unsigned long strtoul(const char *nptr, char **endptr, int base)
{
	const char *s = nptr;
	unsigned long acc;
	int c;
	unsigned long cutoff;
	int neg = 0, any, cutlim;

	/*
	 * See strtol for comments as to the logic used.
	 */
	do {
		c = *s++;
	} while (isspace(c));
	if (c == '-') {
		neg = 1;
		c = *s++;
	} else if (c == '+')
		c = *s++;
	if ((base == 0 || base == 16) &&
	    c == '0' && (*s == 'x' || *s == 'X')) {
		c = s[1];
		s += 2;
		base = 16;
	}
	if (base == 0)
		base = c == '0' ? 8 : 10;
	cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
	cutlim = (int)((unsigned long)ULONG_MAX % (unsigned long)base);
	for (acc = 0, any = 0;; c = *s++) {
		if (isdigit(c))
			c -= '0';
		else if (isalpha(c))
			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
		else
			break;
		if (c >= base)
			break;
		if (any < 0 || acc > cutoff || acc == cutoff && c > cutlim)
			any = -1;
		else {
			any = 1;
			acc *= base;
			acc += c;
		}
	}
	if (any < 0) {
		acc = ULONG_MAX;
		errno = ERANGE;
	} else if (neg)
		acc = -acc;
	if (endptr != 0)
		*endptr = (char *) (any ? s - 1 : nptr);
	return (acc);
}
#endif /* HAVE_STRTOUL */

#ifndef HAVE_SETLINEBUF
 int setlinebuf(FILE *stream)
{
	return setvbuf(stream, (char *)NULL, _IOLBF, 0);
}
#endif /* HAVE_SETLINEBUF */

#ifndef HAVE_VSYSLOG
#ifdef HAVE_SYSLOG
 void vsyslog (int facility_priority, char *format, va_list arglist)
{
	char *msg = NULL;
	vasprintf(&msg, format, arglist);
	if (!msg)
		return;
	syslog(facility_priority, "%s", msg);
	SAFE_FREE(msg);
}
#endif /* HAVE_SYSLOG */
#endif /* HAVE_VSYSLOG */


#ifndef HAVE_TIMEGM
/*
  yes, I know this looks insane, but its really needed. The function in the 
  Linux timegm() manpage does not work on solaris.
*/
 time_t timegm(struct tm *tm) 
{
	struct tm tm2, tm3;
	time_t t;

	tm2 = *tm;

	t = mktime(&tm2);
	tm3 = *localtime(&t);
	tm2 = *tm;
	tm2.tm_isdst = tm3.tm_isdst;
	t = mktime(&tm2);
	t -= TimeDiff(t);

	return t;
}
#endif

#ifndef HAVE_SETENV
 int setenv(const char *name, const char *value, int overwrite) 
{
	char *p = NULL;
	int ret = -1;

	asprintf(&p, "%s=%s", name, value);

	if (overwrite || getenv(name)) {
		if (p) ret = putenv(p);
	} else {
		ret = 0;
	}

	return ret;	
}
#endif
