Vendor things

third-party/vendor/ttf-parser-0.15.2/src/tables/svg.rs

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+//! An [SVG Table](https://docs.microsoft.com/en-us/typography/opentype/spec/svg) implementation.
+
+use crate::GlyphId;
+use crate::parser::{FromData, LazyArray16, NumFrom, Offset, Offset32, Stream};
+
+#[derive(Clone, Copy)]
+struct SvgDocumentRecord {
+    start_glyph_id: GlyphId,
+    end_glyph_id: GlyphId,
+    svg_doc_offset: Option<Offset32>,
+    svg_doc_length: u32,
+}
+
+impl FromData for SvgDocumentRecord {
+    const SIZE: usize = 12;
+
+    #[inline]
+    fn parse(data: &[u8]) -> Option<Self> {
+        let mut s = Stream::new(data);
+        Some(SvgDocumentRecord {
+            start_glyph_id: s.read::<GlyphId>()?,
+            end_glyph_id: s.read::<GlyphId>()?,
+            svg_doc_offset: s.read::<Option<Offset32>>()?,
+            svg_doc_length: s.read::<u32>()?,
+        })
+    }
+}
+
+
+/// A list of [SVG documents](
+/// https://docs.microsoft.com/en-us/typography/opentype/spec/svg#svg-document-list).
+#[derive(Clone, Copy)]
+pub struct SvgDocumentsList<'a> {
+    data: &'a [u8],
+    records: LazyArray16<'a, SvgDocumentRecord>,
+}
+
+impl<'a> SvgDocumentsList<'a> {
+    /// Returns SVG document data at index.
+    ///
+    /// `index` is not a GlyphId. You should use [`find()`](SvgDocumentsList::find) instead.
+    #[inline]
+    pub fn get(&self, index: u16) -> Option<&'a [u8]> {
+        let record = self.records.get(index)?;
+        let offset = record.svg_doc_offset?.to_usize();
+        self.data.get(offset..offset + usize::num_from(record.svg_doc_length))
+    }
+
+    /// Returns a SVG document data by glyph ID.
+    #[inline]
+    pub fn find(&self, glyph_id: GlyphId) -> Option<&'a [u8]> {
+        let index = self.records.into_iter()
+            .position(|v| (v.start_glyph_id..=v.end_glyph_id).contains(&glyph_id))?;
+        self.get(index as u16)
+    }
+
+    /// Returns the number of SVG documents in the list.
+    pub fn len(&self) -> u16 {
+        self.records.len()
+    }
+}
+
+impl core::fmt::Debug for SvgDocumentsList<'_> {
+    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
+        write!(f, "SvgDocumentsList {{ ... }}")
+    }
+}
+
+impl<'a> IntoIterator for SvgDocumentsList<'a,> {
+    type Item = &'a [u8];
+    type IntoIter = SvgDocumentsListIter<'a>;
+
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        SvgDocumentsListIter {
+            list: self,
+            index: 0,
+        }
+    }
+}
+
+
+/// An iterator over [`SvgDocumentsList`] values.
+#[derive(Clone, Copy)]
+#[allow(missing_debug_implementations)]
+pub struct SvgDocumentsListIter<'a> {
+    list: SvgDocumentsList<'a>,
+    index: u16,
+}
+
+impl<'a> Iterator for SvgDocumentsListIter<'a> {
+    type Item = &'a [u8];
+
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.index < self.list.len() {
+            self.index += 1;
+            self.list.get(self.index - 1)
+        } else {
+            None
+        }
+    }
+
+    #[inline]
+    fn count(self) -> usize {
+        usize::from(self.list.len().checked_sub(self.index).unwrap_or(0))
+    }
+}
+
+
+/// An [SVG Table](https://docs.microsoft.com/en-us/typography/opentype/spec/svg).
+#[derive(Clone, Copy, Debug)]
+pub struct Table<'a> {
+    /// A list of SVG documents.
+    pub documents: SvgDocumentsList<'a>,
+}
+
+impl<'a> Table<'a> {
+    /// Parses a table from raw data.
+    pub fn parse(data: &'a [u8]) -> Option<Self> {
+        let mut s = Stream::new(data);
+        s.skip::<u16>(); // version
+        let doc_list_offset = s.read::<Option<Offset32>>()??;
+
+        let mut s = Stream::new_at(data, doc_list_offset.to_usize())?;
+        let count = s.read::<u16>()?;
+        let records = s.read_array16::<SvgDocumentRecord>(count)?;
+
+        Some(Table {
+            documents: SvgDocumentsList {
+                data: &data[doc_list_offset.0 as usize..],
+                records,
+            }
+        })
+    }
+}