| // https://docs.microsoft.com/en-us/typography/opentype/spec/maxp |
| |
| use core::num::NonZeroU16; |
| |
| use crate::parser::Stream; |
| |
| // We care only about `numGlyphs`. |
| pub fn parse(data: &[u8]) -> Option<NonZeroU16> { |
| let mut s = Stream::new(data); |
| let version: u32 = s.read()?; |
| if !(version == 0x00005000 || version == 0x00010000) { |
| return None; |
| } |
| |
| let n: u16 = s.read()?; |
| NonZeroU16::new(n) |
| } |
| |
| |
| #[cfg(test)] |
| mod tests { |
| #[test] |
| fn version_05() { |
| let num_glyphs = super::parse(&[ |
| 0x00, 0x00, 0x50, 0x00, // version: 0.3125 |
| 0x00, 0x01, // number of glyphs: 1 |
| ]).map(|n| n.get()); |
| assert_eq!(num_glyphs, Some(1)); |
| } |
| |
| #[test] |
| fn version_1_full() { |
| let num_glyphs = super::parse(&[ |
| 0x00, 0x01, 0x00, 0x00, // version: 1 |
| 0x00, 0x01, // number of glyphs: 1 |
| 0x00, 0x00, // maximum points in a non-composite glyph: 0 |
| 0x00, 0x00, // maximum contours in a non-composite glyph: 0 |
| 0x00, 0x00, // maximum points in a composite glyph: 0 |
| 0x00, 0x00, // maximum contours in a composite glyph: 0 |
| 0x00, 0x00, // maximum zones: 0 |
| 0x00, 0x00, // maximum twilight points: 0 |
| 0x00, 0x00, // number of Storage Area locations: 0 |
| 0x00, 0x00, // number of FDEFs: 0 |
| 0x00, 0x00, // number of IDEFs: 0 |
| 0x00, 0x00, // maximum stack depth: 0 |
| 0x00, 0x00, // maximum byte count for glyph instructions: 0 |
| 0x00, 0x00, // maximum number of components: 0 |
| 0x00, 0x00, // maximum levels of recursion: 0 |
| ]).map(|n| n.get()); |
| assert_eq!(num_glyphs, Some(1)); |
| } |
| |
| #[test] |
| fn version_1_trimmed() { |
| // We don't really care about the data after the number of glyphs. |
| let num_glyphs = super::parse(&[ |
| 0x00, 0x01, 0x00, 0x00, // version: 1 |
| 0x00, 0x01, // number of glyphs: 1 |
| ]).map(|n| n.get()); |
| assert_eq!(num_glyphs, Some(1)); |
| } |
| |
| #[test] |
| fn unknown_version() { |
| let num_glyphs = super::parse(&[ |
| 0x00, 0x00, 0x00, 0x00, // version: 0 |
| 0x00, 0x01, // number of glyphs: 1 |
| ]).map(|n| n.get()); |
| assert_eq!(num_glyphs, None); |
| } |
| |
| #[test] |
| fn zero_glyphs() { |
| let num_glyphs = super::parse(&[ |
| 0x00, 0x00, 0x50, 0x00, // version: 0.3125 |
| 0x00, 0x00, // number of glyphs: 0 |
| ]).map(|n| n.get()); |
| assert_eq!(num_glyphs, None); |
| } |
| |
| // TODO: what to do when the number of glyphs is 0xFFFF? |
| // we're actually checking this in loca |
| } |
