move stuff into files

crates/linker/src/generate_dylib/mod.rs

@@ -0,0 +1,63 @@
+use target_lexicon::Triple;
+
+mod elf64;
+mod pe;
+
+/// an empty shared library, that we build on top of
+const DUMMY_ELF64: &[u8] = include_bytes!("../../dummy-elf64-x86-64.so");
+
+pub fn generate(target: &Triple, custom_names: &[String]) -> object::read::Result<Vec<u8>> {
+    match target.binary_format {
+        target_lexicon::BinaryFormat::Elf => elf64::create_dylib_elf64(DUMMY_ELF64, custom_names),
+        target_lexicon::BinaryFormat::Macho => todo!("macho dylib creation"),
+        target_lexicon::BinaryFormat::Coff => Ok(pe::synthetic_dll(custom_names)),
+        other => unimplemented!("dylib creation for {:?}", other),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use object::Object;
+
+    fn check_exports(target: &Triple) {
+        let custom_names = ["foo".to_string(), "bar".to_string()];
+
+        let bytes = generate(target, &custom_names).unwrap();
+        let object = object::File::parse(bytes.as_slice()).unwrap();
+
+        let exports = object.exports().unwrap();
+        for custom in custom_names {
+            assert!(
+                exports.iter().any(|e| e.name() == custom.as_bytes()),
+                "missing {}",
+                &custom
+            );
+        }
+    }
+
+    #[test]
+    fn check_exports_elf64() {
+        let target = target_lexicon::Triple {
+            architecture: target_lexicon::Architecture::X86_64,
+            operating_system: target_lexicon::OperatingSystem::Linux,
+            binary_format: target_lexicon::BinaryFormat::Elf,
+            ..target_lexicon::Triple::host()
+        };
+
+        check_exports(&target);
+    }
+
+    #[test]
+    fn check_exports_coff() {
+        let target = target_lexicon::Triple {
+            architecture: target_lexicon::Architecture::X86_64,
+            operating_system: target_lexicon::OperatingSystem::Windows,
+            binary_format: target_lexicon::BinaryFormat::Coff,
+            ..target_lexicon::Triple::host()
+        };
+
+        check_exports(&target);
+    }
+}