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/* SPDX-License-Identifier: LGPL-2.1-only */
/*
* lib/data.c Abstract Data
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation version 2.1
* of the License.
*
* Copyright (c) 2003-2012 Thomas Graf <tgraf@suug.ch>
*/
/**
* @ingroup core_types
* @defgroup data Abstract Data
*
* Abstract data type representing a binary data blob.
*
* Related sections in the development guide:
* - @core_doc{_abstract_data, Abstract Data}
*
* @{
*
* Header
* ------
* ~~~~{.c}
* #include <netlink/data.h>
* ~~~~
*/
#include <netlink-private/netlink.h>
#include <netlink/netlink.h>
#include <netlink/utils.h>
#include <linux/socket.h>
/**
* @name General
* @{
*/
/**
* Allocate a new abstract data object.
* @arg buf Data buffer containing the actual data.
* @arg size Size of data buffer.
*
* Allocates a new abstract data and copies the specified data
* buffer into the new handle.
*
* @return Newly allocated data handle or NULL
*/
struct nl_data *nl_data_alloc(const void *buf, size_t size)
{
struct nl_data *data;
data = calloc(1, sizeof(*data));
if (!data)
goto errout;
data->d_data = calloc(1, size);
if (!data->d_data) {
free(data);
goto errout;
}
data->d_size = size;
if (buf)
memcpy(data->d_data, buf, size);
return data;
errout:
return NULL;
}
/**
* Allocate abstract data object based on netlink attribute.
* @arg nla Netlink attribute of unspecific type.
*
* Allocates a new abstract data and copies the payload of the
* attribute to the abstract data object.
*
* @see nla_data_alloc
* @return Newly allocated data handle or NULL
*/
struct nl_data *nl_data_alloc_attr(const struct nlattr *nla)
{
return nl_data_alloc(nla_data(nla), nla_len(nla));
}
/**
* Clone an abstract data object.
* @arg src Abstract data object
*
* @return Cloned object or NULL
*/
struct nl_data *nl_data_clone(const struct nl_data *src)
{
return nl_data_alloc(src->d_data, src->d_size);
}
/**
* Append data to an abstract data object.
* @arg data Abstract data object.
* @arg buf Data buffer containing the data to be appended.
* @arg size Size of data to be apppended.
*
* Reallocates an abstract data and copies the specified data
* buffer into the new handle.
*
* @return 0 on success or a negative error code
*/
int nl_data_append(struct nl_data *data, const void *buf, size_t size)
{
if (size > 0) {
char *d_data = realloc(data->d_data, data->d_size + size);
if (!d_data)
return -NLE_NOMEM;
if (buf)
memcpy(d_data + data->d_size, buf, size);
else
memset(d_data + data->d_size, 0, size);
data->d_data = d_data;
data->d_size += size;
}
return 0;
}
/**
* Free an abstract data object.
* @arg data Abstract data object.
*/
void nl_data_free(struct nl_data *data)
{
if (data)
free(data->d_data);
free(data);
}
/** @} */
/**
* @name Attribute Access
* @{
*/
/**
* Get data buffer of abstract data object.
* @arg data Abstract data object.
* @return Data buffer or NULL if empty.
*/
void *nl_data_get(const struct nl_data *data)
{
if (data->d_size > 0)
return (void*)data->d_data;
return NULL;
}
/**
* Get size of data buffer of abstract data object.
* @arg data Abstract data object.
* @return Size of data buffer.
*/
size_t nl_data_get_size(const struct nl_data *data)
{
return data->d_size;
}
/** @} */
/**
* @name Misc
* @{
*/
/**
* Compare two abstract data objects.
* @arg a Abstract data object.
* @arg b Another abstract data object.
* @return An integer less than, equal to, or greater than zero if
* a is found, respectively, to be less than, to match, or
* be greater than b.
*/
int nl_data_cmp(const struct nl_data *a, const struct nl_data *b)
{
const void *a_ = nl_data_get(a);
const void *b_ = nl_data_get(b);
if (a_ && b_)
return memcmp(a_, b_, nl_data_get_size(a));
else
return -1;
}
/** @} */
/** @} */