embedded_sdmmc/
structure.rs

1//! embedded-sdmmc-rs - Useful macros for parsing SD/MMC structures.
2
3macro_rules! access_field {
4    ($self:expr, $offset:expr, $start_bit:expr, 1) => {
5        ($self.data[$offset] & (1 << $start_bit)) != 0
6    };
7    ($self:expr, $offset:expr, $start:expr, $num_bits:expr) => {
8        ($self.data[$offset] >> $start) & (((1u16 << $num_bits) - 1) as u8)
9    };
10}
11
12macro_rules! define_field {
13    ($name:ident, bool, $offset:expr, $bit:expr) => {
14        pub fn $name(&self) -> bool {
15            access_field!(self, $offset, $bit, 1)
16        }
17    };
18    ($name:ident, u8, $offset:expr, $start_bit:expr, $num_bits:expr) => {
19        pub fn $name(&self) -> u8 {
20            access_field!(self, $offset, $start_bit, $num_bits)
21        }
22    };
23    ($name:ident, $type:ty, [ $( ( $offset:expr, $start_bit:expr, $num_bits:expr ) ),+ ]) => {
24        pub fn $name(&self) -> $type {
25            let mut result = 0;
26            $(
27                    result <<= $num_bits;
28                    let part = access_field!(self, $offset, $start_bit, $num_bits) as $type;
29                    result |=  part;
30            )+
31            result
32        }
33    };
34
35    ($name:ident, u8, $offset:expr) => {
36        pub fn $name(&self) -> u8 {
37            self.data[$offset]
38        }
39    };
40
41    ($name:ident, u16, $offset:expr) => {
42        pub fn $name(&self) -> u16 {
43            LittleEndian::read_u16(&self.data[$offset..$offset+2])
44        }
45    };
46
47    ($name:ident, u32, $offset:expr) => {
48        pub fn $name(&self) -> u32 {
49            LittleEndian::read_u32(&self.data[$offset..$offset+4])
50        }
51    };
52}
53
54// ****************************************************************************
55//
56// End Of File
57//
58// ****************************************************************************