/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*

 * CMS array functions.

 */

#include "cmslocal.h"

#include "secerr.h"

/*

 * ARRAY FUNCTIONS

 *

 * In NSS, arrays are rather primitive arrays of pointers.

 * Makes it easy to walk the array, but hard to count elements

 * and manage the storage.

 *

 * This is a feeble attempt to encapsulate the functionality

 * and get rid of hundreds of lines of similar code

 */

/*

 * NSS_CMSArray_Alloc - allocate an array in an arena

 *

 * This allocates space for the array of pointers

 */

void **

NSS_CMSArray_Alloc(PLArenaPool *poolp, int n)

{

    return (void **)PORT_ArenaZAlloc(poolp, n * sizeof(void *));

}

/*

 * NSS_CMSArray_Add - add an element to the end of an array

 *

 * The array of pointers is either created (if array was empty before) or grown.

 */

SECStatus

NSS_CMSArray_Add(PLArenaPool *poolp, void ***array, void *obj)

{

    void **p;

    int n;

    void **dest;

    PORT_Assert(array != NULL);

    if (array == NULL)

        return SECFailure;

    if (*array == NULL) {

        dest = (void **)PORT_ArenaAlloc(poolp, 2 * sizeof(void *));

        n = 0;

    } else {

        n = 0;

        p = *array;

        while (*p++)

            n++;

        dest = (void **)PORT_ArenaGrow(poolp,

                                       *array,

                                       (n + 1) * sizeof(void *),

                                       (n + 2) * sizeof(void *));

    }

    if (dest == NULL)

        return SECFailure;

    dest[n] = obj;

    dest[n + 1] = NULL;

    *array = dest;

    return SECSuccess;

}

/*

 * NSS_CMSArray_IsEmpty - check if array is empty

 */

PRBool

NSS_CMSArray_IsEmpty(void **array)

{

    return (array == NULL || array[0] == NULL);

}

/*

 * NSS_CMSArray_Count - count number of elements in array

 */

int

NSS_CMSArray_Count(void **array)

{

    int n = 0;

    if (array == NULL)

        return 0;

    while (*array++ != NULL)

        n++;

    return n;

}

/*

 * NSS_CMSArray_Sort - sort an array in place

 *

 * If "secondary" or "tertiary are not NULL, it must be arrays with the same

 *  number of elements as "primary". The same reordering will get applied to it.

 *

 * "compare" is a function that returns

 *  < 0 when the first element is less than the second

 *  = 0 when the first element is equal to the second

 *  > 0 when the first element is greater than the second

 * to acheive ascending ordering.

 */

void

NSS_CMSArray_Sort(void **primary, int (*compare)(void *, void *), void **secondary, void **tertiary)

{

    int n, i, limit, lastxchg;

    void *tmp;

    n = NSS_CMSArray_Count(primary);

    PORT_Assert(secondary == NULL || NSS_CMSArray_Count(secondary) == n);

    PORT_Assert(tertiary == NULL || NSS_CMSArray_Count(tertiary) == n);

    if (n <= 1) /* ordering is fine */

        return;

    /* yes, ladies and gentlemen, it's BUBBLE SORT TIME! */

    limit = n - 1;

    while (1) {

        lastxchg = 0;

        for (i = 0; i < limit; i++) {

            if ((*compare)(primary[i], primary[i + 1]) > 0) {

                /* exchange the neighbours */

                tmp = primary[i + 1];

                primary[i + 1] = primary[i];

                primary[i] = tmp;

                if (secondary) {            /* secondary array? */

                    tmp = secondary[i + 1]; /* exchange there as well */

                    secondary[i + 1] = secondary[i];

                    secondary[i] = tmp;

                }

                if (tertiary) {            /* tertiary array? */

                    tmp = tertiary[i + 1]; /* exchange there as well */

                    tertiary[i + 1] = tertiary[i];

                    tertiary[i] = tmp;

                }

                lastxchg = i + 1; /* index of the last element bubbled up */

            }

        }

        if (lastxchg == 0) /* no exchanges, so array is sorted */

            break;         /* we're done */

        limit = lastxchg;  /* array is sorted up to [limit] */

    }

}

#if 0

/* array iterator stuff... not used */

typedef void **NSSCMSArrayIterator;

/* iterator */

NSSCMSArrayIterator

NSS_CMSArray_First(void **array)

{

    if (array == NULL || array[0] == NULL)

    return NULL;

    return (NSSCMSArrayIterator)&(array[0]);

}

void *

NSS_CMSArray_Obj(NSSCMSArrayIterator iter)

{

    void **p = (void **)iter;

    return *iter;   /* which is NULL if we are at the end of the array */

}

NSSCMSArrayIterator

NSS_CMSArray_Next(NSSCMSArrayIterator iter)

{

    void **p = (void **)iter;

    return (NSSCMSArrayIterator)(p + 1);

}

#endif