/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000-2003 The Apache Software Foundation.  All rights
 * reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
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 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
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 *    not be used to endorse or promote products derived from this
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 * 5. Products derived from this software may not be called "Apache",
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 *
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 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

#include "apr.h"
#include "apr_private.h"
#include "apr_general.h"
#include "apr_strings.h"
#include "apr_mmap.h"
#include "apr_errno.h"
#include "apr_arch_file_io.h"
#include "apr_portable.h"

/* System headers required for the mmap library */
#ifdef BEOS
#include <kernel/OS.h>
#endif
#if APR_HAVE_STRING_H
#include <string.h>
#endif
#if APR_HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif

#if APR_HAS_MMAP || defined(BEOS)

static apr_status_t mmap_cleanup(void *themmap)
{
    apr_mmap_t *mm = themmap;
    apr_mmap_t *next = APR_RING_NEXT(mm,link);
    int rv = 0;

    /* we no longer refer to the mmaped region */
    APR_RING_REMOVE(mm,link);
    APR_RING_NEXT(mm,link) = NULL;
    APR_RING_PREV(mm,link) = NULL;

    if (next != mm) {
        /* more references exist, so we're done */
        return APR_SUCCESS;
    }

#ifdef BEOS
    rv = delete_area(mm->area);
#else
    rv = munmap(mm->mm, mm->size);
#endif
    mm->mm = (void *)-1;

    if (rv == 0) {
        return APR_SUCCESS;
    }
    return errno;
}

APR_DECLARE(apr_status_t) apr_mmap_create(apr_mmap_t **new, 
                                          apr_file_t *file, apr_off_t offset, 
                                          apr_size_t size, apr_int32_t flag, 
                                          apr_pool_t *cont)
{
    void *mm;
#ifdef BEOS
    area_id aid = -1;
    uint32 pages = 0;
#else
    apr_int32_t native_flags = 0;
#endif

    if (size == 0)
        return APR_EINVAL;
    
    if (file == NULL || file->filedes == -1 || file->buffered)
        return APR_EBADF;
    (*new) = (apr_mmap_t *)apr_pcalloc(cont, sizeof(apr_mmap_t));
    
#ifdef BEOS
    /* XXX: mmap shouldn't really change the seek offset */
    apr_file_seek(file, APR_SET, &offset);

    /* There seems to be some strange interactions that mean our area must
     * be set as READ & WRITE or writev will fail!  Go figure...
     * So we ignore the value in flags and always ask for both READ and WRITE
     */
    pages = (size + B_PAGE_SIZE -1) / B_PAGE_SIZE;
    aid = create_area("apr_mmap", &mm , B_ANY_ADDRESS, pages * B_PAGE_SIZE,
        B_NO_LOCK, B_WRITE_AREA|B_READ_AREA);

    if (aid < B_NO_ERROR) {
        /* we failed to get an area we can use... */
        *new = NULL;
        return APR_ENOMEM;
    }

    if (aid >= B_NO_ERROR)
        read(file->filedes, mm, size);
    
    (*new)->area = aid;
#else

    if (flag & APR_MMAP_WRITE) {
        native_flags |= PROT_WRITE;
    }
    if (flag & APR_MMAP_READ) {
        native_flags |= PROT_READ;
    }

    mm = mmap(NULL, size, native_flags, MAP_SHARED, file->filedes, offset);

    if (mm == (void *)-1) {
        /* we failed to get an mmap'd file... */
        *new = NULL;
        return errno;
    }
#endif

    (*new)->mm = mm;
    (*new)->size = size;
    (*new)->cntxt = cont;
    APR_RING_ELEM_INIT(*new, link);

    /* register the cleanup... */
    apr_pool_cleanup_register((*new)->cntxt, (void*)(*new), mmap_cleanup,
             apr_pool_cleanup_null);
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_mmap_dup(apr_mmap_t **new_mmap,
                                       apr_mmap_t *old_mmap,
                                       apr_pool_t *p,
                                       int transfer_ownership)
{
    *new_mmap = (apr_mmap_t *)apr_pmemdup(p, old_mmap, sizeof(apr_mmap_t));
    (*new_mmap)->cntxt = p;

    APR_RING_INSERT_AFTER(old_mmap, *new_mmap, link);

    apr_pool_cleanup_register(p, *new_mmap, mmap_cleanup,
                              apr_pool_cleanup_null);
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_mmap_delete(apr_mmap_t *mm)
{
    return apr_pool_cleanup_run(mm->cntxt, mm, mmap_cleanup);
}

#endif