feat(core): implement dynamic section string table and symbol resolution

crates/molotov-core/src/dynamic.rs

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+use std::collections::HashMap;
+
+#[derive(Debug, Clone)]
+pub struct ElfSymbol {
+    pub name_offset: u32,
+    pub info: u8,
+    pub other: u8,
+    pub shndx: u16,
+    pub value: u64,
+    pub size: u64,
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct DynamicSection<'a> {
+    pub strtab: &'a [u8],
+    pub symbols: Vec<ElfSymbol>,
+    pub name_to_index: HashMap<String, usize>,
+}
+
+impl<'a> DynamicSection<'a> {
+    pub fn new_with_strtab(strtab: &'a [u8]) -> Self {
+        Self {
+            strtab,
+            symbols: Vec::new(),
+            name_to_index: HashMap::new(),
+        }
+    }
+
+    pub fn lookup_string(&self, offset: usize) -> Option<&'a str> {
+        if offset >= self.strtab.len() {
+            return None;
+        }
+
+        let slice = &self.strtab[offset..];
+        let null_pos = slice.iter().position(|&b| b == 0)?;
+        std::str::from_utf8(&slice[..null_pos]).ok()
+    }
+
+    pub fn register_symbol(&mut self, sym: ElfSymbol) {
+        if let Some(name) = self.lookup_string(sym.name_offset as usize) {
+            self.name_to_index.insert(name.to_string(), self.symbols.len());
+        }
+        self.symbols.push(sym);
+    }
+
+    pub fn find_symbol(&self, name: &str) -> Option<&ElfSymbol> {
+        let idx = self.name_to_index.get(name)?;
+        self.symbols.get(*idx)
+    }
+}

crates/molotov-core/src/lib.rs

@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
+pub mod dynamic;
 pub mod elf;
 pub mod mmap;
 pub mod symbols;

crates/molotov-core/tests/dynamic_test.rs

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+use molotov_core::dynamic::DynamicSection;
+
+#[test]
+fn test_string_table_lookup() {
+    let strtab = b"\0JNI_OnLoad\0ANativeActivity_onCreate\0";
+    let dynamic = DynamicSection::new_with_strtab(strtab);
+
+    assert_eq!(dynamic.lookup_string(1), Some("JNI_OnLoad"));
+    assert_eq!(dynamic.lookup_string(12), Some("ANativeActivity_onCreate"));
+    assert_eq!(dynamic.lookup_string(999), None);
+}