scuffle_mp4/boxes/types/
url.rs

use std::io;

use byteorder::{ReadBytesExt, WriteBytesExt};
use bytes::Bytes;

use crate::boxes::header::{BoxHeader, FullBoxHeader};
use crate::boxes::traits::BoxType;

#[derive(Debug, Clone, PartialEq)]
/// Url Box
/// ISO/IEC 14496-12:2022(E) - 8.7.2.2
pub struct Url {
    pub header: FullBoxHeader,
    pub location: Option<String>,
}

impl Default for Url {
    fn default() -> Self {
        Self::new()
    }
}

impl Url {
    pub fn new() -> Self {
        Self {
            header: FullBoxHeader::new(Self::NAME, 0, 1),
            location: None,
        }
    }
}

impl BoxType for Url {
    const NAME: [u8; 4] = *b"url ";

    fn demux(header: BoxHeader, data: Bytes) -> io::Result<Self> {
        let mut reader = io::Cursor::new(data);

        let header = FullBoxHeader::demux(header, &mut reader)?;

        let location = if header.flags == 0 {
            let mut location = String::new();
            loop {
                let byte = reader.read_u8()?;
                if byte == 0 {
                    break;
                }
                location.push(byte as char);
            }

            Some(location)
        } else {
            None
        };

        Ok(Self { header, location })
    }

    fn primitive_size(&self) -> u64 {
        self.header.size()
            + if let Some(location) = &self.location {
                location.len() as u64 + 1 // null terminator
            } else {
                0
            }
    }

    fn primitive_mux<T: io::Write>(&self, writer: &mut T) -> io::Result<()> {
        self.header.mux(writer)?;

        if let Some(location) = &self.location {
            writer.write_all(location.as_bytes())?;
            writer.write_u8(0)?;
        }

        Ok(())
    }

    fn validate(&self) -> io::Result<()> {
        if self.header.version != 0 {
            return Err(io::Error::new(io::ErrorKind::InvalidData, "url version must be 0"));
        }

        if self.header.flags != 0 && self.location.is_some() {
            return Err(io::Error::new(
                io::ErrorKind::InvalidData,
                "url location must be empty if flags is 1",
            ));
        } else if self.header.flags == 0 && self.location.is_none() {
            return Err(io::Error::new(
                io::ErrorKind::InvalidData,
                "url location must be present if flags is 0",
            ));
        }

        Ok(())
    }
}
scuffle_mp4/boxes/types/url.rs

scuffle_mp4/boxes/types/
url.rs
