parsing should work

1 files changed, 38 insertions, 7 deletions

diff --git a/ebml/src/lib.rs b/ebml/src/lib.rs
index 7445bbc..22af473 100644
--- a/ebml/src/lib.rs
+++ b/ebml/src/lib.rs
@@ -16,13 +16,6 @@ pub trait ValueFromBuf: Sized {
 
 impl ValueFromBuf for u64 {
     fn from_buf(buf: &[u8]) -> anyhow::Result<Self> {
-        // if buf.len() != 8 {
-        //     bail!("u64 is not 64 bits long")
-        // }
-        // Ok((buf[0] as u64) << 24
-        //     | (buf[1] as u64) << 16
-        //     | (buf[2] as u64) << 8
-        //     | (buf[3] as u64) << 0)
         if buf.len() > 8 {
             bail!("u64 too big")
         }
@@ -34,6 +27,34 @@ impl ValueFromBuf for u64 {
         Ok(val)
     }
 }
+impl ValueFromBuf for i64 {
+    fn from_buf(buf: &[u8]) -> anyhow::Result<Self> {
+        if buf.len() > 8 {
+            bail!("i64 too big")
+        }
+        Ok(if buf[0] > 127 {
+            if buf.len() == 8 {
+                i64::from_be_bytes(buf.try_into().unwrap())
+            } else {
+                -((1 << (buf.len() * 8)) - (u64::from_buf(buf)? as i64))
+            }
+        } else {
+            u64::from_buf(buf)? as i64
+        })
+    }
+}
+impl ValueFromBuf for f64 {
+    fn from_buf(buf: &[u8]) -> anyhow::Result<Self> {
+        Ok(if buf.len() == 4 {
+            f32::from_be_bytes(buf.try_into().unwrap()) as f64
+        } else if buf.len() == 8 {
+            f64::from_be_bytes(buf.try_into().unwrap())
+        } else {
+            bail!("float is not 4 or 8 bytes long");
+        })
+    }
+}
+
 impl ValueFromBuf for Vec<u8> {
     fn from_buf(buf: &[u8]) -> anyhow::Result<Self> {
         Ok(buf.to_vec())
@@ -44,3 +65,13 @@ impl ValueFromBuf for String {
         Ok(String::from_utf8(Vec::from(buf))?)
     }
 }
+impl ValueFromBuf for Master {
+    /// this has an internal usage, where buf has len of 1, when an end should be constructed
+    fn from_buf(buf: &[u8]) -> anyhow::Result<Self> {
+        Ok(match buf.len() {
+            0 => Master::Start,
+            1 => Master::End,
+            _ => unreachable!(),
+        })
+    }
+}