wkb 0.9.2

Fast, pure-Rust reader and writer for Well-Known Binary geometries
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use byteorder::{BigEndian, LittleEndian};

use crate::{common::WkbGeometryCode, error::WkbError, Endianness};
use std::io::{Cursor, Error};

pub(crate) trait ReadBytesExt: byteorder::ReadBytesExt {
    fn read_u32(&mut self, byte_order: Endianness) -> Result<u32, Error> {
        match byte_order {
            Endianness::BigEndian => byteorder::ReadBytesExt::read_u32::<BigEndian>(self),
            Endianness::LittleEndian => byteorder::ReadBytesExt::read_u32::<LittleEndian>(self),
        }
    }

    fn read_f64(&mut self, byte_order: Endianness) -> Result<f64, Error> {
        match byte_order {
            Endianness::BigEndian => byteorder::ReadBytesExt::read_f64::<BigEndian>(self),
            Endianness::LittleEndian => byteorder::ReadBytesExt::read_f64::<LittleEndian>(self),
        }
    }
}

/// All types that implement `Read` get methods defined in `ReadBytesExt`
/// for free.
impl<R: std::io::Read + ?Sized> ReadBytesExt for R {}

/// Return `true` if this WKB item is EWKB and has an embedded SRID
pub(crate) fn has_srid(buf: &[u8], byte_order: Endianness) -> Result<bool, WkbError> {
    // Read geometry code to see if an SRID exists.
    let mut reader = Cursor::new(buf);

    // Skip 1-byte byte order that we already know
    reader.set_position(1);

    let geometry_code = WkbGeometryCode::new(reader.read_u32(byte_order)?);
    Ok(geometry_code.has_srid())
}