/* Copyright (C) 2007-2023 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 Anoop Saldanha <anoopsaldanha@gmail.com>

 */

#include "suricata-common.h"

#include "suricata.h"

#include "util-debug.h"

#include "util-buffer.h"

/* 10 mb */

#define MAX_LIMIT 10485760

MemBuffer *MemBufferCreateNew(uint32_t size)

{

    sc_errno = SC_OK;

    if (size > MAX_LIMIT) {

        SCLogWarning("Mem buffer asked to create "

                     "buffer with size greater than API limit - %d",

                MAX_LIMIT);

        sc_errno = SC_EINVAL;

        return NULL;

    }

    size_t total_size = size + sizeof(MemBuffer);

    MemBuffer *buffer = SCCalloc(1, total_size);

    if (unlikely(buffer == NULL)) {

        sc_errno = SC_ENOMEM;

        return NULL;

    }

    buffer->size = size;

    return buffer;

}

/** \brief expand membuffer by size of 'expand_by'

 *

 *  If expansion failed, buffer will still be valid.

 *

 *  \retval result 0 ok, -1 expansion failed

 */

int MemBufferExpand(MemBuffer **buffer, uint32_t expand_by) {

    if (((*buffer)->size + expand_by) > MAX_LIMIT) {

        SCLogWarning("Mem buffer asked to create "

                     "buffer with size greater than API limit - %d",

                MAX_LIMIT);

        return -1;

    }

    /* Adjust expand_by to next multiple of 4k. */

    if (expand_by % 4096 != 0) {

        expand_by = expand_by - (expand_by % 4096) + 4096;

    }

    size_t total_size = (*buffer)->size + sizeof(MemBuffer) + expand_by;

    MemBuffer *tbuffer = SCRealloc(*buffer, total_size);

    if (unlikely(tbuffer == NULL)) {

        return -1;

    }

    *buffer = tbuffer;

    (*buffer)->size += expand_by;

    SCLogDebug("expanded buffer by %u, size is now %u", expand_by, (*buffer)->size);

    return 0;

}

void MemBufferFree(MemBuffer *buffer)

{

    SCFree(buffer);

    return;

}

void MemBufferPrintToFP(MemBuffer *buffer, FILE *fp)

{

    for (uint32_t i = 0; i < buffer->offset; i++) {

        if (isprint(buffer->buffer[i]))

            fprintf(fp, "%c", buffer->buffer[i]);

        else

            fprintf(fp, "|%02X|", buffer->buffer[i]);

    }

}

size_t MemBufferPrintToFPAsString(MemBuffer *b, FILE *fp)

{

    return fwrite(MEMBUFFER_BUFFER(b), sizeof(uint8_t), MEMBUFFER_OFFSET(b), fp);

}

void MemBufferPrintToFPAsHex(MemBuffer *b, FILE *fp)

{

    for (uint32_t i = 0; i < MEMBUFFER_OFFSET(b); i++) {

        if (MEMBUFFER_OFFSET(b) % 8 == 0)

            fprintf(fp, "\n");

        fprintf(fp, " %02X", b->buffer[i]);

    }

}

uint32_t MemBufferWriteRaw(MemBuffer *dst, const uint8_t *raw, const uint32_t raw_len)

{

    uint32_t write_len;

    if (raw_len >= dst->size - dst->offset) {

        SCLogDebug("Truncating data write since it exceeded buffer limit of %" PRIu32, dst->size);

        write_len = dst->size - dst->offset - 1;

    } else {

        write_len = raw_len;

    }

    memcpy(dst->buffer + dst->offset, raw, write_len);

    dst->offset += write_len;

    dst->buffer[dst->offset] = '\0';

    return write_len;

}

void MemBufferWriteString(MemBuffer *dst, const char *fmt, ...)

{

    uint32_t available = dst->size - dst->offset;

    uint32_t max_string_size = MIN(available, 2048);

    va_list ap;

    char string[max_string_size];

    va_start(ap, fmt);

    int written = vsnprintf(string, sizeof(string), fmt, ap);

    va_end(ap);

    if (written < 0) {

        return;

    } else if ((uint32_t)written > max_string_size) {

        SCLogDebug("Truncating data write since it exceeded buffer "

                   "limit of %" PRIu32,

                dst->size);

    }

    size_t string_size = strlen(string);

    memcpy(dst->buffer + dst->offset, string, string_size);

    dst->offset += string_size;

    dst->buffer[dst->offset] = '\0';

}