/* 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/. */

/*

 * Support routines for SECItem data structure.

 */

#include "seccomon.h"

#include "secitem.h"

#include "secerr.h"

#include "secport.h"

SECItem *

SECITEM_AllocItem(PLArenaPool *arena, SECItem *item, unsigned int len)

{

    SECItem *result = NULL;

    void *mark = NULL;

    if (arena != NULL) {

	mark = PORT_ArenaMark(arena);

    }

    if (item == NULL) {

	if (arena != NULL) {

	    result = PORT_ArenaZAlloc(arena, sizeof(SECItem));

	} else {

	    result = PORT_ZAlloc(sizeof(SECItem));

	}

	if (result == NULL) {

	    goto loser;

	}

    } else {

	PORT_Assert(item->data == NULL);

	result = item;

    }

    result->len = len;

    if (len) {

	if (arena != NULL) {

	    result->data = PORT_ArenaAlloc(arena, len);

	} else {

	    result->data = PORT_Alloc(len);

	}

	if (result->data == NULL) {

	    goto loser;

	}

    } else {

	result->data = NULL;

    }

    if (mark) {

	PORT_ArenaUnmark(arena, mark);

    }

    return(result);

loser:

    if ( arena != NULL ) {

	if (mark) {

	    PORT_ArenaRelease(arena, mark);

	}

	if (item != NULL) {

	    item->data = NULL;

	    item->len = 0;

	}

    } else {

	if (result != NULL) {

	    SECITEM_FreeItem(result, (item == NULL) ? PR_TRUE : PR_FALSE);

	}

	/*

	 * If item is not NULL, the above has set item->data and

	 * item->len to 0.

	 */

    }

    return(NULL);

}

SECStatus

SECITEM_ReallocItem(PLArenaPool *arena, SECItem *item, unsigned int oldlen,

		    unsigned int newlen)

{

    PORT_Assert(item != NULL);

    if (item == NULL) {

	/* XXX Set error.  But to what? */

	return SECFailure;

    }

    /*

     * If no old length, degenerate to just plain alloc.

     */

    if (oldlen == 0) {

	PORT_Assert(item->data == NULL || item->len == 0);

	if (newlen == 0) {

	    /* Nothing to do.  Weird, but not a failure.  */

	    return SECSuccess;

	}

	item->len = newlen;

	if (arena != NULL) {

	    item->data = PORT_ArenaAlloc(arena, newlen);

	} else {

	    item->data = PORT_Alloc(newlen);

	}

    } else {

	if (arena != NULL) {

	    item->data = PORT_ArenaGrow(arena, item->data, oldlen, newlen);

	} else {

	    item->data = PORT_Realloc(item->data, newlen);

	}

    }

    if (item->data == NULL) {

	return SECFailure;

    }

    return SECSuccess;

}

SECStatus

SECITEM_ReallocItemV2(PLArenaPool *arena, SECItem *item, unsigned int newlen)

{

    unsigned char *newdata = NULL;

    PORT_Assert(item);

    if (!item) {

	PORT_SetError(SEC_ERROR_INVALID_ARGS);

	return SECFailure;

    }

    if (item->len == newlen) {

	return SECSuccess;

    }

    if (!newlen) {

	if (!arena) {

	    PORT_Free(item->data);

	}

	item->data = NULL;

	item->len = 0;

	return SECSuccess;

    }

    if (!item->data) {

	/* allocate fresh block of memory */

	PORT_Assert(!item->len);

	if (arena) {

	    newdata = PORT_ArenaAlloc(arena, newlen);

	} else {

	    newdata = PORT_Alloc(newlen);

	}

    } else {

	/* reallocate or adjust existing block of memory */

	if (arena) {

	    if (item->len > newlen) {

		/* There's no need to realloc a shorter block from the arena,

		 * because it would result in using even more memory!

		 * Therefore we'll continue to use the old block and 

		 * set the item to the shorter size.

		 */

		item->len = newlen;

		return SECSuccess;

	    }

	    newdata = PORT_ArenaGrow(arena, item->data, item->len, newlen);

	} else {

	    newdata = PORT_Realloc(item->data, newlen);

	}

    }

    if (!newdata) {

	PORT_SetError(SEC_ERROR_NO_MEMORY);

	return SECFailure;

    }

    item->len = newlen;

    item->data = newdata;

    return SECSuccess;

}

SECComparison

SECITEM_CompareItem(const SECItem *a, const SECItem *b)

{

    unsigned m;

    int rv;

    if (a == b)

    	return SECEqual;

    if (!a || !a->len || !a->data) 

        return (!b || !b->len || !b->data) ? SECEqual : SECLessThan;

    if (!b || !b->len || !b->data) 

    	return SECGreaterThan;

    m = ( ( a->len < b->len ) ? a->len : b->len );

    rv = PORT_Memcmp(a->data, b->data, m);

    if (rv) {

	return rv < 0 ? SECLessThan : SECGreaterThan;

    }

    if (a->len < b->len) {

	return SECLessThan;

    }

    if (a->len == b->len) {

	return SECEqual;

    }

    return SECGreaterThan;

}

PRBool

SECITEM_ItemsAreEqual(const SECItem *a, const SECItem *b)

{

    if (a->len != b->len)

        return PR_FALSE;

    if (!a->len)

    	return PR_TRUE;

    if (!a->data || !b->data) {

        /* avoid null pointer crash. */

	return (PRBool)(a->data == b->data);

    }

    return (PRBool)!PORT_Memcmp(a->data, b->data, a->len);

}

SECItem *

SECITEM_DupItem(const SECItem *from)

{

    return SECITEM_ArenaDupItem(NULL, from);

}

SECItem *

SECITEM_ArenaDupItem(PLArenaPool *arena, const SECItem *from)

{

    SECItem *to;

    if ( from == NULL ) {

	return(NULL);

    }

    if ( arena != NULL ) {

	to = (SECItem *)PORT_ArenaAlloc(arena, sizeof(SECItem));

    } else {

	to = (SECItem *)PORT_Alloc(sizeof(SECItem));

    }

    if ( to == NULL ) {

	return(NULL);

    }

    if ( arena != NULL ) {

	to->data = (unsigned char *)PORT_ArenaAlloc(arena, from->len);

    } else {

	to->data = (unsigned char *)PORT_Alloc(from->len);

    }

    if ( to->data == NULL ) {

	PORT_Free(to);

	return(NULL);

    }

    to->len = from->len;

    to->type = from->type;

    if ( to->len ) {

	PORT_Memcpy(to->data, from->data, to->len);

    }

    return(to);

}

SECStatus

SECITEM_CopyItem(PLArenaPool *arena, SECItem *to, const SECItem *from)

{

    to->type = from->type;

    if (from->data && from->len) {

	if ( arena ) {

	    to->data = (unsigned char*) PORT_ArenaAlloc(arena, from->len);

	} else {

	    to->data = (unsigned char*) PORT_Alloc(from->len);

	}

	if (!to->data) {

	    return SECFailure;

	}

	PORT_Memcpy(to->data, from->data, from->len);

	to->len = from->len;

    } else {

	/*

	 * If from->data is NULL but from->len is nonzero, this function

	 * will succeed.  Is this right?

	 */

	to->data = 0;

	to->len = 0;

    }

    return SECSuccess;

}

void

SECITEM_FreeItem(SECItem *zap, PRBool freeit)

{

    if (zap) {

	PORT_Free(zap->data);

	zap->data = 0;

	zap->len = 0;

	if (freeit) {

	    PORT_Free(zap);

	}

    }

}

void

SECITEM_ZfreeItem(SECItem *zap, PRBool freeit)

{

    if (zap) {

	PORT_ZFree(zap->data, zap->len);

	zap->data = 0;

	zap->len = 0;

	if (freeit) {

	    PORT_ZFree(zap, sizeof(SECItem));

	}

    }

}

/* these reroutines were taken from pkix oid.c, which is supposed to

 * replace this file some day */

/*

 * This is the hash function.  We simply XOR the encoded form with

 * itself in sizeof(PLHashNumber)-byte chunks.  Improving this

 * routine is left as an excercise for the more mathematically

 * inclined student.

 */

PLHashNumber PR_CALLBACK

SECITEM_Hash ( const void *key)

{

    const SECItem *item = (const SECItem *)key;

    PLHashNumber rv = 0;

    PRUint8 *data = (PRUint8 *)item->data;

    PRUint32 i;

    PRUint8 *rvc = (PRUint8 *)&rv;

    for( i = 0; i < item->len; i++ ) {

        rvc[ i % sizeof(rv) ] ^= *data;

        data++;

    }

    return rv;

}

/*

 * This is the key-compare function.  It simply does a lexical

 * comparison on the item data.  This does not result in

 * quite the same ordering as the "sequence of numbers" order,

 * but heck it's only used internally by the hash table anyway.

 */

PRIntn PR_CALLBACK

SECITEM_HashCompare ( const void *k1, const void *k2)

{

    const SECItem *i1 = (const SECItem *)k1;

    const SECItem *i2 = (const SECItem *)k2;

    return SECITEM_ItemsAreEqual(i1,i2);

}

SECItemArray *

SECITEM_AllocArray(PLArenaPool *arena, SECItemArray *array, unsigned int len)

{

    SECItemArray *result = NULL;

    void *mark = NULL;

    if (array != NULL && array->items != NULL) {

        PORT_Assert(0);

        PORT_SetError(SEC_ERROR_INVALID_ARGS);

        return NULL;

    }

    if (arena != NULL) {

        mark = PORT_ArenaMark(arena);

    }

    if (array == NULL) {

        if (arena != NULL) {

            result = PORT_ArenaZAlloc(arena, sizeof(SECItemArray));

        } else {

            result = PORT_ZAlloc(sizeof(SECItemArray));

        }

        if (result == NULL) {

            goto loser;

        }

    } else {

        result = array;

    }

    result->len = len;

    if (len) {

        if (arena != NULL) {

            result->items = PORT_ArenaZNewArray(arena, SECItem, len);

        } else {

            result->items = PORT_ZNewArray(SECItem, len);

        }

        if (result->items == NULL) {

            goto loser;

        }

    } else {

        result->items = NULL;

    }

    if (mark) {

        PORT_ArenaUnmark(arena, mark);

    }

    return result;

loser:

    if ( arena != NULL ) {

        if (mark) {

            PORT_ArenaRelease(arena, mark);

        }

    } else {

        if (result != NULL && array == NULL) {

            PORT_Free(result);

        }

    }

    if (array != NULL) {

        array->items = NULL;

        array->len = 0;

    }

    return NULL;

}

static void

secitem_FreeArray(SECItemArray *array, PRBool zero_items, PRBool freeit)

{

    unsigned int i;

    if (!array || !array->len || !array->items)

        return;

    for (i = 0; i < array->len; ++i) {

        SECItem *item = &array->items[i];

        if (item->data) {

            if (zero_items) {

                SECITEM_ZfreeItem(item, PR_FALSE);

            } else {

                SECITEM_FreeItem(item, PR_FALSE);

            }

        }

    }

    PORT_Free(array->items);

    array->items = NULL;

    array->len = 0;

    if (freeit)

        PORT_Free(array);

}

void SECITEM_FreeArray(SECItemArray *array, PRBool freeit)

{

    secitem_FreeArray(array, PR_FALSE, freeit);

}

void SECITEM_ZfreeArray(SECItemArray *array, PRBool freeit)

{

    secitem_FreeArray(array, PR_TRUE, freeit);

}

SECItemArray *

SECITEM_DupArray(PLArenaPool *arena, const SECItemArray *from)

{

    SECItemArray *result;

    unsigned int i;

    /* Require a "from" array.

     * Reject an inconsistent "from" array with NULL data and nonzero length.

     * However, allow a "from" array of zero length.

     */

    if (!from || (!from->items && from->len))

        return NULL;

    result = SECITEM_AllocArray(arena, NULL, from->len);

    if (!result)

        return NULL;

    for (i = 0; i < from->len; ++i) {

        SECStatus rv = SECITEM_CopyItem(arena,

                                        &result->items[i], &from->items[i]);

        if (rv != SECSuccess) {

            SECITEM_ZfreeArray(result, PR_TRUE);

            return NULL;

        }

    }

    return result;

}