Add minimal robot factory functionality and arc archive support for #6

rc_core/src/data/mod.rs

@@ -28,6 +28,22 @@ pub fn encode_7_bit_i32(mut src: i32) -> Vec<u8> {
     out
 }
 
+pub fn decode_7_bit_i32(reader: &mut dyn std::io::Read) -> std::io::Result<i32> {
+    let mut buf = [0u8; 1];
+    let mut out: i32 = 0;
+    for _ in 0..5 {
+        reader.read_exact(&mut buf)?;
+        let byte = buf[0];
+        let has_more = byte & 0x80;
+        let number = byte & 0x7F;
+        out = (out << 7) | (number as i32);
+        if has_more == 0 {
+            return Ok(out);
+        }
+    }
+    Ok(out)
+}
+
 pub fn write_str_for_binreader(s: &str, writer: &mut dyn std::io::Write) -> std::io::Result<usize> {
     let s_bytes = s.as_bytes();
     let mut total_len = writer.write(&encode_7_bit_i32(s_bytes.len() as i32))?;
@@ -35,6 +51,13 @@ pub fn write_str_for_binreader(s: &str, writer: &mut dyn std::io::Write) -> std:
     Ok(total_len)
 }
 
+pub fn read_str_for_binwriter(reader: &mut dyn std::io::Read) -> std::io::Result<String> {
+    let len = decode_7_bit_i32(reader)?;
+    let mut buf = vec![0u8; len as usize];
+    reader.read_exact(&mut buf)?;
+    Ok(String::from_utf8_lossy(&buf).into_owned())
+}
+
 pub fn cube_id_to_str(id: u32) -> String {
     hex::encode(id.to_be_bytes()).into()
 }