rohc_buf_prepend

NAME
SYNOPSIS
DESCRIPTION
PARAMETERS
STRUCTURES
SEE ALSO

NAME

rohc_buf_prepend − Add data at the beginning of the given network buffer.

SYNOPSIS

#include <rohc/rohc.h>

void rohc_buf_prepend(
struct rohc_buf *const buf
,
const uint8_t *const data
,
const size_t len

);

DESCRIPTION

PARAMETERS

buf

The network buffer to prepend data to

data

The data to prepend

len

The length (in bytes) of the data to prepend

STRUCTURES

A network buffer for the ROHC library
May represent one uncompressed packet, one ROHC packet, or a ROHC feedback.

The network buffer does not contain the packet data itself. It only has a pointer on it. This is designed this way for performance reasons: no copy required to initialize a network buffer, the struct is small and may be passed as copy to function.

The network buffer is able to keep some free space at its beginning. The unused space at the beginning of the buffer may be used to prepend a network header at the very end of the packet handling.

The beginning of the network buffer may also be shifted forward with the rohc_buf_pull function or shifted backward with the rohc_buf_push function. This is useful when parsing a network packet (once bytes are read, shift them forward) for example.

The network buffer may be initialized manually (see below) or with the helper functions rohc_buf_init_empty or rohc_buf_init_full...

struct rohc_buf {
struct rohc_ts time; /* The timestamp associated to the data */
uint8_t *data; /* The buffer data */
size_t max_len; /* The maximum length of the buffer */
size_t offset; /* The offset for the beginning of the data */
size_t len; /* The data length (in bytes) */
};

SEE ALSO

rohc.h(3)