locker.c
1.99 KB
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/* GNU mailutils - a suite of utilities for electronic mail
Copyright (C) 1999, 2000 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Library 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 Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <locker.h>
#include <errno.h>
#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
/*
* Waiting for Brian E. to implement this.
*/
struct _locker
{
char *filename;
size_t filename_len;
int lock;
};
int
locker_init (locker_t *plocker, char *filename, size_t len)
{
locker_t l;
if (plocker == NULL)
return EINVAL;
if (filename == NULL || len == 0)
return EINVAL;
l = malloc (sizeof(*l));
if (l == NULL)
return ENOMEM;
l->filename = calloc (len + 1, sizeof(char));
if (l->filename == NULL)
{
free (l);
return ENOMEM;
}
memcpy (l->filename, filename, len);
l->lock = 0;
l->filename_len = len;
*plocker = l;
return 0;
}
void
locker_destroy (locker_t *plocker)
{
if (plocker && *plocker)
{
free ((*plocker)->filename);
free (*plocker);
*plocker = NULL;
}
}
int
locker_lock (locker_t locker, int flags)
{
(void)flags;
if (locker == NULL)
return EINVAL;
locker->lock++;
return 0;
}
int
locker_touchlock (locker_t locker)
{
if (locker == NULL)
return EINVAL;
return 0;
}
int
locker_unlock (locker_t locker)
{
if (locker == NULL)
return EINVAL;
locker->lock--;
return 0;
}