/* Copyright (C) 2007-2010 Open Information Security Foundation
 *
 * You can copy, redistribute or modify this Program under the terms of
 * the GNU General Public License version 2 as published by the Free
 * Software Foundation.
 *
 * 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
 * version 2 along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

/**
 * \file
 *
 * \author Victor Julien <victor@inliniac.net>
 *
 * Pool utility functions
 */

#include "suricata-common.h"
#include "util-pool.h"
#include "util-unittest.h"
#include "util-debug.h"

Pool *PoolInit(uint32_t size, uint32_t prealloc_size, void *(*Alloc)(void *), void *AllocData, void (*Free)(void *))
{
    Pool *p = NULL;

    if (Alloc == NULL) {
        //printf("ERROR: PoolInit no Hash function\n");
        goto error;
    }

    if (size != 0 && prealloc_size > size)
        goto error;

    /* setup the filter */
    p = SCMalloc(sizeof(Pool));
    if (p == NULL)
        goto error;

    memset(p,0,sizeof(Pool));

    p->max_buckets = size;
    p->Alloc = Alloc;
    p->AllocData = AllocData;
    p->Free  = Free;

    /* alloc the buckets and place them in the empty list */
    uint32_t u32 = 0;
    if (size > 0) {
        PoolBucket *pb = SCCalloc(size, sizeof(PoolBucket));
        p->pb_buffer = pb;
        if (pb == NULL)
            goto error;
        memset(pb, 0, size * sizeof(PoolBucket));
        for (u32 = 0; u32 < size; u32++) {
            /* populate pool */
            pb->next = p->empty_list;
            pb->flags |= POOL_BUCKET_PREALLOCATED;
            p->empty_list = pb;
            p->empty_list_size++;
            pb++;
        }
    }

    /* prealloc the buckets and requeue them to the alloc list */
    for (u32 = 0; u32 < prealloc_size; u32++) {
        if (size == 0) { /* unlimited */
            PoolBucket *pb = SCMalloc(sizeof(PoolBucket));
            if (pb == NULL)
                goto error;

            memset(pb, 0, sizeof(PoolBucket));

            pb->data = p->Alloc(p->AllocData);
            p->allocated++;

            pb->next = p->alloc_list;
            p->alloc_list = pb;
            p->alloc_list_size++;
        } else {
            PoolBucket *pb = p->empty_list;
            if (pb == NULL)
                goto error;

            p->empty_list = pb->next;
            p->empty_list_size--;

            pb->data = p->Alloc(p->AllocData);
            p->allocated++;

            pb->next = p->alloc_list;
            p->alloc_list = pb;
            p->alloc_list_size++;
        }
    }

    return p;

error:
    if (p != NULL) {
        PoolFree(p);
    }
    return NULL;
}

void PoolFree(Pool *p) {
    if (p == NULL)
        return;

    while (p->alloc_list != NULL) {
        PoolBucket *pb = p->alloc_list;
        p->alloc_list = pb->next;
        p->Free(pb->data);
        pb->data = NULL;
        if (! pb->flags & POOL_BUCKET_PREALLOCATED) {
            SCFree(pb);
        }
    }

    while (p->empty_list != NULL) {
        PoolBucket *pb = p->empty_list;
        p->empty_list = pb->next;
        if (pb->data!= NULL) {
            p->Free(pb->data);
            pb->data = NULL;
        }
        if (! pb->flags & POOL_BUCKET_PREALLOCATED) {
            SCFree(pb);
        }
    }

    if (p->pb_buffer)
        SCFree(p->pb_buffer);
    SCFree(p);
}

void PoolPrint(Pool *p) {
    printf("\n----------- Hash Table Stats ------------\n");
    printf("Buckets:               %" PRIu32 "\n", p->empty_list_size + p->alloc_list_size);
    printf("-----------------------------------------\n");
}

void *PoolGet(Pool *p) {
    SCEnter();

    PoolBucket *pb = p->alloc_list;
    if (pb != NULL) {
        /* pull from the alloc list */
        p->alloc_list = pb->next;
        p->alloc_list_size--;

        /* put in the empty list */
        pb->next = p->empty_list;
        p->empty_list = pb;
        p->empty_list_size++;
    } else {
        if (p->max_buckets == 0 || p->allocated < p->max_buckets) {
            SCLogDebug("max_buckets %"PRIu32"", p->max_buckets);
            p->allocated++;

            p->outstanding++;
            if (p->outstanding > p->max_outstanding)
                p->max_outstanding = p->outstanding;

            SCReturnPtr(p->Alloc(p->AllocData), "void");
        } else {
            SCReturnPtr(NULL, "void");
        }
    }

    void *ptr = pb->data;
    pb->data = NULL;
    p->outstanding++;
    if (p->outstanding > p->max_outstanding)
        p->max_outstanding = p->outstanding;
    SCReturnPtr(ptr,"void");
}

void PoolReturn(Pool *p, void *data) {
    SCEnter();

    PoolBucket *pb = p->empty_list;

    SCLogDebug("pb %p", pb);

    if (pb == NULL) {
        p->allocated--;
        p->outstanding--;
        if (p->Free != NULL)
            p->Free(data);

        SCLogDebug("tried to return data %p to the pool %p, but no more "
                   "buckets available. Just freeing the data.", data, p);
        SCReturn;
    }

    /* pull from the alloc list */
    p->empty_list = pb->next;
    p->empty_list_size--;

    /* put in the alloc list */
    pb->next = p->alloc_list;
    p->alloc_list = pb;
    p->alloc_list_size++;

    pb->data = data;
    p->outstanding--;
    SCReturn;
}

void PoolPrintSaturation(Pool *p) {
    SCLogDebug("pool %p is using %"PRIu32" out of %"PRIu32" items (%02.1f%%), max %"PRIu32" (%02.1f%%): pool struct memory %"PRIu64".", p, p->outstanding, p->max_buckets, (float)(p->outstanding/(float)(p->max_buckets))*100, p->max_outstanding, (float)(p->max_outstanding/(float)(p->max_buckets))*100, (uint64_t)(p->max_buckets * sizeof(PoolBucket)));
}

/*
 * ONLY TESTS BELOW THIS COMMENT
 */

void *PoolTestAlloc(void *allocdata) {
    void *ptr = SCMalloc(10);
    return ptr;
}
void *PoolTestAllocArg(void *allocdata) {
    size_t len = strlen((char *)allocdata) + 1;
    char *str = SCMalloc(len);
    if (str != NULL)
        strlcpy(str,(char *)allocdata,len);
    return (void *)str;
}

void PoolTestFree(void *ptr) {
    SCFree(ptr);
}

#ifdef UNITTESTS
static int PoolTestInit01 (void) {
    Pool *p = PoolInit(10,5,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        return 0;

    PoolFree(p);
    return 1;
}

static int PoolTestInit02 (void) {
    int retval = 0;

    Pool *p = PoolInit(10,5,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        goto end;

    if (p->alloc_list == NULL || p->empty_list == NULL) {
        printf("list(s) not properly initialized (a:%p e:%p): ",
            p->alloc_list, p->empty_list);
        retval = 0;
        goto end;
    }

    if (p->Alloc != PoolTestAlloc) {
        printf("Alloc func ptr %p != %p: ",
            p->Alloc, PoolTestAlloc);
        retval = 0;
        goto end;
    }

    if (p->Free != PoolTestFree) {
        printf("Free func ptr %p != %p: ",
            p->Free, PoolTestFree);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (p != NULL)
        PoolFree(p);
    return retval;
}

static int PoolTestInit03 (void) {
    int retval = 0;
    void *data = NULL;

    Pool *p = PoolInit(10,5,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        goto end;

    data = PoolGet(p);
    if (data == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (p->alloc_list_size != 4) {
        printf("p->alloc_list_size 4 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    if (p->empty_list_size != 6) {
        printf("p->empty_list_size 6 != %" PRIu32 ": ", p->empty_list_size);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (data != NULL)
        SCFree(data);
    if (p != NULL)
        PoolFree(p);
    return retval;
}

static int PoolTestInit04 (void) {
    int retval = 0;
    char *str = NULL;

    Pool *p = PoolInit(10,5,PoolTestAllocArg,(void *)"test",PoolTestFree);
    if (p == NULL)
        goto end;

    str = PoolGet(p);
    if (str == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (strcmp(str, "test") != 0) {
        printf("Memory not properly initialized: ");
        retval = 0;
        goto end;
    }

    if (p->alloc_list_size != 4) {
        printf("p->alloc_list_size 4 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    if (p->empty_list_size != 6) {
        printf("p->empty_list_size 6 != %" PRIu32 ": ", p->empty_list_size);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (str != NULL)
        SCFree(str);
    if (p != NULL)
        PoolFree(p);
    return retval;
}

static int PoolTestInit05 (void) {
    int retval = 0;
    void *data = NULL;

    Pool *p = PoolInit(10,5,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        goto end;

    data = PoolGet(p);
    if (data == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (p->alloc_list_size != 4) {
        printf("p->alloc_list_size 4 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    if (p->empty_list_size != 6) {
        printf("p->empty_list_size 6 != %" PRIu32 ": ", p->empty_list_size);
        retval = 0;
        goto end;
    }

    PoolReturn(p, data);
    data = NULL;

    if (p->alloc_list_size != 5) {
        printf("p->alloc_list_size 5 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    if (p->empty_list_size != 5) {
        printf("p->empty_list_size 5 != %" PRIu32 ": ", p->empty_list_size);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (data != NULL)
        SCFree(data);
    if (p != NULL)
        PoolFree(p);
    return retval;
}

static int PoolTestInit06 (void) {
    int retval = 0;
    void *data = NULL;
    void *data2 = NULL;

    Pool *p = PoolInit(1,0,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        goto end;

    if (p->allocated != 0) {
        printf("p->allocated 0 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    data = PoolGet(p);
    if (data == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (p->allocated != 1) {
        printf("p->allocated 1 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    data2 = PoolGet(p);
    if (data2 != NULL) {
        printf("PoolGet returned %p, expected NULL: ", data2);
        retval = 0;
        goto end;
    }

    PoolReturn(p,data);
    data = NULL;

    if (p->allocated != 1) {
        printf("p->allocated 1 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    if (p->alloc_list_size != 1) {
        printf("p->alloc_list_size 1 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (data != NULL)
        SCFree(data);
    if (data2 != NULL)
        SCFree(data2);
    if (p != NULL)
        PoolFree(p);
    return retval;
}

/** \test pool with unlimited size */
static int PoolTestInit07 (void) {
    int retval = 0;
    void *data = NULL;
    void *data2 = NULL;

    Pool *p = PoolInit(0,1,PoolTestAlloc,NULL,PoolTestFree);
    if (p == NULL)
        goto end;

    if (p->max_buckets != 0) {
        printf("p->max_buckets 0 != %" PRIu32 ": ", p->max_buckets);
        retval = 0;
        goto end;
    }

    if (p->allocated != 1) {
        printf("p->allocated 1 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    data = PoolGet(p);
    if (data == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (p->allocated != 1) {
        printf("(2) p->allocated 1 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    data2 = PoolGet(p);
    if (data2 == NULL) {
        printf("PoolGet returned NULL: ");
        retval = 0;
        goto end;
    }

    if (p->allocated != 2) {
        printf("(3) p->allocated 2 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    PoolReturn(p,data);
    data = NULL;

    if (p->allocated != 2) {
        printf("(4) p->allocated 2 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    if (p->alloc_list_size != 1) {
        printf("p->alloc_list_size 1 != %" PRIu32 ": ", p->alloc_list_size);
        retval = 0;
        goto end;
    }

    PoolReturn(p,data2);
    data2 = NULL;

    if (p->allocated != 1) {
        printf("(5) p->allocated 1 != %" PRIu32 ": ", p->allocated);
        retval = 0;
        goto end;
    }

    retval = 1;
end:
    if (data != NULL)
        SCFree(data);
    if (data2 != NULL)
        SCFree(data2);
    if (p != NULL)
        PoolFree(p);
    return retval;
}
#endif /* UNITTESTS */

void PoolRegisterTests(void) {
#ifdef UNITTESTS
    UtRegisterTest("PoolTestInit01", PoolTestInit01, 1);
    UtRegisterTest("PoolTestInit02", PoolTestInit02, 1);
    UtRegisterTest("PoolTestInit03", PoolTestInit03, 1);
    UtRegisterTest("PoolTestInit04", PoolTestInit04, 1);
    UtRegisterTest("PoolTestInit05", PoolTestInit05, 1);
    UtRegisterTest("PoolTestInit06", PoolTestInit06, 1);
    UtRegisterTest("PoolTestInit07", PoolTestInit07, 1);
#endif /* UNITTESTS */
}