/*

 zip_buffer.c -- bounds checked access to memory buffer

 Copyright (C) 2014-2024 Dieter Baron and Thomas Klausner

 This file is part of libzip, a library to manipulate ZIP archives.

 The authors can be contacted at <info@libzip.org>

 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.

 3. The names of the authors may not be used to endorse or promote

 products derived from this software without specific prior

 written permission.

 THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS

 OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY

 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE

 GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER

 IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN

 IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include <stdlib.h>

#include <string.h>

#include "zipint.h"

zip_uint8_t *

_zip_buffer_data(zip_buffer_t *buffer) {

    return buffer->data;

}

void

_zip_buffer_free(zip_buffer_t *buffer) {

    if (buffer == NULL) {

        return;

    }

    if (buffer->free_data) {

        free(buffer->data);

    }

    free(buffer);

}

bool

_zip_buffer_eof(zip_buffer_t *buffer) {

    return buffer->ok && buffer->offset == buffer->size;

}

zip_uint8_t *

_zip_buffer_get(zip_buffer_t *buffer, zip_uint64_t length) {

    zip_uint8_t *data;

    data = _zip_buffer_peek(buffer, length);

    if (data != NULL) {

        buffer->offset += length;

    }

    return data;

}

zip_uint16_t

_zip_buffer_get_16(zip_buffer_t *buffer) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 2);

    if (data == NULL) {

        return 0;

    }

    return (zip_uint16_t)(data[0] + (data[1] << 8));

}

zip_uint32_t

_zip_buffer_get_32(zip_buffer_t *buffer) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 4);

    if (data == NULL) {

        return 0;

    }

    return ((((((zip_uint32_t)data[3] << 8) + data[2]) << 8) + data[1]) << 8) + data[0];

}

zip_uint64_t

_zip_buffer_get_64(zip_buffer_t *buffer) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 8);

    if (data == NULL) {

        return 0;

    }

    return ((zip_uint64_t)data[7] << 56) + ((zip_uint64_t)data[6] << 48) + ((zip_uint64_t)data[5] << 40) + ((zip_uint64_t)data[4] << 32) + ((zip_uint64_t)data[3] << 24) + ((zip_uint64_t)data[2] << 16) + ((zip_uint64_t)data[1] << 8) + (zip_uint64_t)data[0];

}

zip_uint8_t

_zip_buffer_get_8(zip_buffer_t *buffer) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 1);

    if (data == NULL) {

        return 0;

    }

    return data[0];

}

zip_uint64_t

_zip_buffer_left(zip_buffer_t *buffer) {

    return buffer->ok ? buffer->size - buffer->offset : 0;

}

zip_uint64_t

_zip_buffer_read(zip_buffer_t *buffer, zip_uint8_t *data, zip_uint64_t length) {

    zip_uint64_t copied;

    if (_zip_buffer_left(buffer) < length) {

        length = _zip_buffer_left(buffer);

    }

    copied = 0;

    while (copied < length) {

        size_t n = ZIP_MIN(length - copied, SIZE_MAX);

        (void)memcpy_s(data + copied, n, _zip_buffer_get(buffer, n), n);

        copied += n;

    }

    return copied;

}

zip_buffer_t *

_zip_buffer_new(zip_uint8_t *data, zip_uint64_t size) {

    bool free_data = (data == NULL);

    zip_buffer_t *buffer;

#if ZIP_UINT64_MAX > SIZE_MAX

    if (size > SIZE_MAX) {

        return NULL;

    }

#endif

    if (data == NULL) {

        if ((data = (zip_uint8_t *)malloc((size_t)size)) == NULL) {

            return NULL;

        }

    }

    if ((buffer = (zip_buffer_t *)malloc(sizeof(*buffer))) == NULL) {

        if (free_data) {

            free(data);

        }

        return NULL;

    }

    buffer->ok = true;

    buffer->data = data;

    buffer->size = size;

    buffer->offset = 0;

    buffer->free_data = free_data;

    return buffer;

}

zip_buffer_t *

_zip_buffer_new_from_source(zip_source_t *src, zip_uint64_t size, zip_uint8_t *buf, zip_error_t *error) {

    zip_buffer_t *buffer;

    if ((buffer = _zip_buffer_new(buf, size)) == NULL) {

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

    if (_zip_read(src, buffer->data, size, error) < 0) {

        _zip_buffer_free(buffer);

        return NULL;

    }

    return buffer;

}

zip_uint64_t

_zip_buffer_offset(zip_buffer_t *buffer) {

    return buffer->ok ? buffer->offset : 0;

}

bool

_zip_buffer_ok(zip_buffer_t *buffer) {

    return buffer->ok;

}

zip_uint8_t *

_zip_buffer_peek(zip_buffer_t *buffer, zip_uint64_t length) {

    zip_uint8_t *data;

    if (!buffer->ok || buffer->offset + length < length || buffer->offset + length > buffer->size) {

        buffer->ok = false;

        return NULL;

    }

    data = buffer->data + buffer->offset;

    return data;

}

int

_zip_buffer_put(zip_buffer_t *buffer, const void *src, size_t length) {

    zip_uint8_t *dst = _zip_buffer_get(buffer, length);

    if (dst == NULL) {

        return -1;

    }

    (void)memcpy_s(dst, length, src, length);

    return 0;

}

int

_zip_buffer_put_16(zip_buffer_t *buffer, zip_uint16_t i) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 2);

    if (data == NULL) {

        return -1;

    }

    data[0] = (zip_uint8_t)(i & 0xff);

    data[1] = (zip_uint8_t)((i >> 8) & 0xff);

    return 0;

}

int

_zip_buffer_put_32(zip_buffer_t *buffer, zip_uint32_t i) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 4);

    if (data == NULL) {

        return -1;

    }

    data[0] = (zip_uint8_t)(i & 0xff);

    data[1] = (zip_uint8_t)((i >> 8) & 0xff);

    data[2] = (zip_uint8_t)((i >> 16) & 0xff);

    data[3] = (zip_uint8_t)((i >> 24) & 0xff);

    return 0;

}

int

_zip_buffer_put_64(zip_buffer_t *buffer, zip_uint64_t i) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 8);

    if (data == NULL) {

        return -1;

    }

    data[0] = (zip_uint8_t)(i & 0xff);

    data[1] = (zip_uint8_t)((i >> 8) & 0xff);

    data[2] = (zip_uint8_t)((i >> 16) & 0xff);

    data[3] = (zip_uint8_t)((i >> 24) & 0xff);

    data[4] = (zip_uint8_t)((i >> 32) & 0xff);

    data[5] = (zip_uint8_t)((i >> 40) & 0xff);

    data[6] = (zip_uint8_t)((i >> 48) & 0xff);

    data[7] = (zip_uint8_t)((i >> 56) & 0xff);

    return 0;

}

int

_zip_buffer_put_8(zip_buffer_t *buffer, zip_uint8_t i) {

    zip_uint8_t *data = _zip_buffer_get(buffer, 1);

    if (data == NULL) {

        return -1;

    }

    data[0] = i;

    return 0;

}

int _zip_buffer_set_offset(zip_buffer_t *buffer, zip_uint64_t offset) {

    if (offset > buffer->size) {

        buffer->ok = false;

        return -1;

    }

    buffer->ok = true;

    buffer->offset = offset;

    return 0;

}

int

_zip_buffer_skip(zip_buffer_t *buffer, zip_uint64_t length) {

    zip_uint64_t offset = buffer->offset + length;

    if (offset < buffer->offset) {

        buffer->ok = false;

        return -1;

    }

    return _zip_buffer_set_offset(buffer, offset);

}

zip_uint64_t

_zip_buffer_size(zip_buffer_t *buffer) {

    return buffer->size;

}