Unify the way of writing a range of data (#64)

Author: bet4it

src/gdbstub_impl/ext/base.rs

@@ -131,16 +131,7 @@ impl<T: Target, C: Connection> GdbStubImpl<T, C> {
                 match xml {
                     Some(xml) => {
                         let xml = xml.trim().as_bytes();
-                        if cmd.offset < xml.len() {
-                            // still more data
-                            res.write_str("m")?;
-                            res.write_binary(
-                                &xml[cmd.offset..][..cmd.len.min(xml.len() - cmd.offset)],
-                            )?
-                        } else {
-                            // no more data
-                            res.write_str("l")?;
-                        }
+                        res.write_binary_range(xml, cmd.offset, cmd.len)?;
                     }
                     // If the target hasn't provided their own XML, then the initial response to
                     // "qSupported" wouldn't have included "qXfer:features:read", and gdb wouldn't

src/gdbstub_impl/ext/memory_map.rs

@@ -17,20 +17,8 @@ impl<T: Target, C: Connection> GdbStubImpl<T, C> {
 
         let handler_status = match command {
             MemoryMap::qXferMemoryMapRead(cmd) => {
-                let xml = ops.memory_map_xml().trim();
-                if cmd.offset >= xml.len() {
-                    // no more data
-                    res.write_str("l")?;
-                } else if cmd.offset + cmd.len >= xml.len() {
-                    // last little bit of data
-                    res.write_str("l")?;
-                    res.write_binary(&xml.as_bytes()[cmd.offset..])?
-                } else {
-                    // still more data
-                    res.write_str("m")?;
-                    res.write_binary(&xml.as_bytes()[cmd.offset..(cmd.offset + cmd.len)])?
-                }
-
+                let xml = ops.memory_map_xml().trim().as_bytes();
+                res.write_binary_range(xml, cmd.offset, cmd.len)?;
                 HandlerStatus::Handled
             }
         };

src/protocol/response_writer.rs

@@ -193,6 +193,25 @@ impl<'a, C: Connection + 'a> ResponseWriter<'a, C> {
         Ok(())
     }
 
+    /// Write a range of data specified by offset and len.
+    /// Used by qXfer:_object_:read commands.
+    pub fn write_binary_range(
+        &mut self,
+        data: &[u8],
+        offset: usize,
+        len: usize,
+    ) -> Result<(), Error<C::Error>> {
+        if offset < data.len() {
+            // still more data
+            self.write_str("m")?;
+            self.write_binary(&data[offset..][..len.min(data.len() - offset)])?
+        } else {
+            // no more data
+            self.write_str("l")?;
+        }
+        Ok(())
+    }
+
     /// Write a number as a big-endian hex string using the most compact
     /// representation possible (i.e: trimming leading zeros).
     pub fn write_num<D: BeBytes + PrimInt>(&mut self, digit: D) -> Result<(), Error<C::Error>> {