/*
 *      cook - file construction tool
 *      Copyright (C) 1991-1994, 1997, 1999, 2001, 2006, 2007 Peter Miller;
 *      All rights reserved.
 *
 *      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., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 * MANIFEST: functions to manipulate dynamic memory
 */

#include <common/ac/stddef.h>
#include <common/ac/string.h>
#include <common/ac/stdlib.h>
#include <common/ac/errno.h>

#include <common/error.h>
#include <common/mem.h>


/*
 * NAME
 *      memory_error - diagnostic
 *
 * SYNOPSIS
 *      void memory_error(void);
 *
 * DESCRIPTION
 *      The memory_error function is used to report fatal problems with the
 *      memory allocator.
 *
 * RETURNS
 *      The memory_error function does not return.
 */

static void
memory_error(void)
{
#ifdef DEBUG
    nerror_raw("memory allocator");
    abort();
#else
    nfatal_raw("memory allocator");
#endif
}


/*
 * NAME
 *      mem_alloc - allocate and clear memory
 *
 * SYNOPSIS
 *      char *mem_alloc(size_t n);
 *
 * DESCRIPTION
 *      Mem_alloc uses malloc to allocate the required sized chunk of memory.
 *      If any error is returned from malloc() an fatal diagnostic is issued.
 *      The memory is zeroed befor it is returned.
 *
 * CAVEAT
 *      It is the responsibility of the caller to ensure that the space is
 *      freed when finished with, by a call to free().
 */

void *
mem_alloc(size_t n)
{
    void            *p;

    if (n < 1)
        n = 1;
    errno = ENOMEM;
    p = malloc(n);
    if (!p)
        memory_error();
    return p;
}


/*
 * NAME
 *      mem_alloc_clear - allocate and clear memory
 *
 * SYNOPSIS
 *      char *mem_alloc_clear(size_t n);
 *
 * DESCRIPTION
 *      Mem_alloc_clear uses malloc to allocate the required sized chunk
 *      of memory.  If any error is returned from malloc() an fatal
 *      diagnostic is issued.  The memory is zeroed befor it is returned.
 *
 * CAVEAT
 *      It is the responsibility of the caller to ensure that the space is
 *      freed when finished with, by a call to free().
 */

void *
mem_alloc_clear(size_t n)
{
    void            *p;

    p = mem_alloc(n);
    memset(p, 0, n);
    return p;
}


void *
mem_change_size(void *p, size_t n)
{
    if (n < 1)
        n = 1;
    errno = ENOMEM;
    if (!p)
        p = malloc(n);
    else
        p = realloc(p, n);
    if (!p)
        memory_error();
    return p;
}


void
mem_free(void *p)
{
    free(p);
}


char *
mem_copy_string(char *s)
{
    char            *cp;
    size_t          len;

    len = strlen(s) + 1;
    cp = mem_alloc(len);
    memcpy(cp, s, len);
    return cp;
}