add map layout feature for dex file

androscalpel_serializer/src/file_reader/map_dex_file.rs

@@ -0,0 +1,57 @@
+//! Most of the logic for the map_dex_file feature.
+
+use crate::DexFileReader;
+
+impl<'a> DexFileReader<'a> {
+    /// List the different structures of the dex file, in order of
+    /// offset, including holes.
+    pub fn get_chunks(&self) -> Vec<(u32, usize, String)> {
+        let dex_size = self.data.len();
+        let mut structs: Vec<_> = self
+            .layout_map
+            .lock()
+            .expect("Failed to acquire mutex lock on layout_map")
+            .iter()
+            .map(|((off, size), desc)| (*off, *size, desc.clone()))
+            .collect();
+        structs.sort();
+        let mut chunks = vec![];
+        let mut last_off = 0;
+        for (off, size, desc) in structs.into_iter() {
+            if off > last_off {
+                let size = (off - last_off) as usize;
+                // ignore padding
+                if (size < 4)
+                    && self.data[last_off as usize..off as usize]
+                        .iter()
+                        .all(|&b| b == 0)
+                {
+                    chunks.push((
+                        last_off,
+                        size,
+                        format!(
+                            "Padding: {:x?}",
+                            &self.data[last_off as usize..off as usize]
+                        ),
+                    ));
+                } else {
+                    chunks.push((last_off, size, "Unreferenced Data".into()));
+                }
+                last_off = off;
+            }
+            // TODO: do something with overlapping struct?
+            if off + size as u32 > last_off {
+                last_off = off + size as u32;
+            }
+            chunks.push((off, size, desc));
+        }
+        if (last_off as usize) < dex_size {
+            chunks.push((
+                last_off,
+                dex_size - last_off as usize,
+                "Unreferenced Data".into(),
+            ));
+        }
+        chunks
+    }
+}