Add support for dynamically loaded libraries

cargo-apk/CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Added `runtime_libs` path to android metadata for packaging extra dynamic libraries into the apk.
+
 # 0.7.0 (2021-05-10)
 
 - Added `cargo apk check`. Useful for compile-testing crates that contain C/C++ dependencies or

cargo-apk/README.md

@@ -87,6 +87,11 @@ icon = "@mipmap/ic_launcher"
 # Defaults to the compiled artifact's name.
 label = "Application Name"
 
+# Folder containing extra shared libraries intended to be dynamically loaded at runtime.
+# Files matching `libs_folder/${android_abi}/*.so` are added to the apk
+# according to the specified build_targets.
+runtime_libs = "path/to/libs_folder"
+
 # See https://developer.android.com/guide/topics/manifest/meta-data-element
 #
 # Note: there can be several .meta_data entries.

cargo-apk/src/apk.rs

@@ -121,28 +121,23 @@ impl<'a> ApkBuilder<'a> {
             manifest.application.label = artifact.name().to_string();
         }
 
-        let assets = self.manifest.assets.as_ref().map(|assets| {
-            dunce::simplified(
-                &self
-                    .cmd
-                    .manifest()
-                    .parent()
-                    .expect("invalid manifest path")
-                    .join(&assets),
-            )
-            .to_owned()
-        });
-        let resources = self.manifest.resources.as_ref().map(|res| {
-            dunce::simplified(
-                &self
-                    .cmd
-                    .manifest()
-                    .parent()
-                    .expect("invalid manifest path")
-                    .join(&res),
-            )
-            .to_owned()
-        });
+        let crate_path = self.cmd.manifest().parent().expect("invalid manifest path");
+
+        let assets = self
+            .manifest
+            .assets
+            .as_ref()
+            .map(|assets| dunce::simplified(&crate_path.join(&assets)).to_owned());
+        let resources = self
+            .manifest
+            .resources
+            .as_ref()
+            .map(|res| dunce::simplified(&crate_path.join(&res)).to_owned());
+        let runtime_libs = self
+            .manifest
+            .runtime_libs
+            .as_ref()
+            .map(|libs| dunce::simplified(&crate_path.join(&libs)).to_owned());
         let apk_name = self
             .manifest
             .apk_name
@@ -190,6 +185,10 @@ impl<'a> ApkBuilder<'a> {
                 .collect::<Vec<_>>();
 
             apk.add_lib_recursively(&artifact, *target, libs_search_paths.as_slice())?;
+
+            if let Some(runtime_libs) = &runtime_libs {
+                apk.add_runtime_libs(runtime_libs, *target, libs_search_paths.as_slice())?;
+            }
         }
 
         Ok(apk.align()?.sign(config.ndk.debug_key()?)?)

cargo-apk/src/manifest.rs

@@ -11,6 +11,7 @@ pub struct Manifest {
     pub build_targets: Vec<Target>,
     pub assets: Option<String>,
     pub resources: Option<String>,
+    pub runtime_libs: Option<String>,
 }
 
 impl Manifest {
@@ -30,6 +31,7 @@ impl Manifest {
             build_targets: metadata.build_targets,
             assets: metadata.assets,
             resources: metadata.resources,
+            runtime_libs: metadata.runtime_libs,
         })
     }
 }
@@ -59,4 +61,5 @@ struct AndroidMetadata {
     build_targets: Vec<Target>,
     assets: Option<String>,
     resources: Option<String>,
+    runtime_libs: Option<String>,
 }

ndk-build/CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Added `add_runtime_libs` function for including extra dynamic libraries in the APK.
+
 # 0.3.0 (2021-05-10)
 
 - New `ApkConfig` field `apk_name` is now used for APK file naming, instead of the application label.

ndk-build/src/apk.rs

@@ -2,6 +2,8 @@ use crate::error::NdkError;
 use crate::manifest::AndroidManifest;
 use crate::ndk::{Key, Ndk};
 use crate::target::Target;
+use std::ffi::OsStr;
+use std::fs;
 use std::path::{Path, PathBuf};
 use std::process::Command;
 
@@ -94,6 +96,23 @@ impl<'a> UnalignedApk<'a> {
         Ok(())
     }
 
+    pub fn add_runtime_libs(
+        &self,
+        path: &Path,
+        target: Target,
+        search_paths: &[&Path],
+    ) -> Result<(), NdkError> {
+        let abi_dir = path.join(target.android_abi());
+        for entry in fs::read_dir(abi_dir)? {
+            let entry = entry?;
+            let path = entry.path();
+            if path.extension() == Some(OsStr::new("so")) {
+                self.add_lib_recursively(&path, target, search_paths)?;
+            }
+        }
+        Ok(())
+    }
+
     pub fn align(self) -> Result<UnsignedApk<'a>, NdkError> {
         let mut zipalign = self.0.build_tool(bin!("zipalign"))?;
         zipalign