Implemented multi-binary app packaging (#648)

Modules/app-posix-module/source/app_posix_loader_service.cpp

@@ -58,19 +58,21 @@ bool is_executable_file(const std::string& resolved_path) {
 #endif
 }
 
-// location.location can be either an app's install directory or the .so file directly; the
-// former resolves to the per-architecture binary at {dir}/elf/posix-{TACTILITY_POSIX_ARCH}.so,
-// mirroring app_esp32_loader_service.cpp's resolve_elf_path().
+// location.location can be either an app's install directory or the .so file directly, mirroring
+// app_esp32_loader_service.cpp's resolve_elf_path(). A "packaged" app's install directory always
+// holds its single binary at the fixed path {dir}/bin/posix-{TACTILITY_POSIX_ARCH}/app.so - a
+// "terminal" app has no such file (its several binaries keep their own names), so this correctly
+// leaves it unresolvable - terminal apps aren't run through AppLoaderApi (see app/install.h).
 error_t resolve_app_path(const std::string& path, std::string& resolvedPath) {
     if (path.ends_with(".so")) {
         resolvedPath = path;
         return ERROR_NONE;
     }
-    std::string shared_object_path = path + "/elf/posix-" TACTILITY_POSIX_ARCH ".so";
-    if (!is_regular_file(shared_object_path)) {
+    std::string candidate = path + "/bin/posix-" TACTILITY_POSIX_ARCH "/app.so";
+    if (!is_regular_file(candidate)) {
         return ERROR_NOT_FOUND;
     }
-    resolvedPath = shared_object_path;
+    resolvedPath = candidate;
     return ERROR_NONE;
 }
 
@@ -94,9 +96,6 @@ error_t api_load(AppLocation location, AppRuntime* out_runtime) {
 
     LOG_I(TAG, "Loading %s", app_path.c_str());
 
-    // RTLD_NOW: a missing symbol fails here, not mid-run(). RTLD_LOCAL: this app's own exported
-    // symbols (if any beyond its entry point) don't leak into the process's global scope and
-    // clash with a different app's.
     void* handle = dlopen(app_path.c_str(), RTLD_NOW | RTLD_LOCAL);
     if (handle == nullptr) {
         LOG_E(TAG, "dlopen(%s) failed: %s", app_path.c_str(), dlerror());
@@ -117,8 +116,8 @@ error_t api_load(AppLocation location, AppRuntime* out_runtime) {
 int32_t api_run(AppRuntime runtime_ptr, uint32_t /*app_instance_id*/, int argc, char* argv[]) {
     auto* runtime = static_cast<PosixAppRuntime*>(runtime_ptr);
 
-    dlerror(); // clear any pending error, per dlsym(3)'s own recommended idiom for telling a NULL
-               // symbol address apart from a real lookup failure
+    // Clear any pending error, per dlsym(3)'s own recommended idiom for telling a NULL symbol address apart from a real lookup failure
+    dlerror();
     void* symbol = dlsym(runtime->handle, "main");
     const char* lookup_error = dlerror();
     if (symbol == nullptr || lookup_error != nullptr) {

Modules/app-posix-module/tests/CMakeLists.txt

@@ -15,14 +15,27 @@ set_target_properties(app_posix_module_test_fixture PROPERTIES POSITION_INDEPEND
 set(NON_ELF_FIXTURE_PATH "${CMAKE_CURRENT_BINARY_DIR}/not-elf.so")
 file(WRITE "${NON_ELF_FIXTURE_PATH}" "not an elf file")
 
+# An install-directory-shaped fixture: {dir}/bin/posix-{arch}/app.so, matching where
+# app_posix_loader_service.cpp's resolve_app_path() looks for a "packaged" app's single binary.
+set(INSTALL_DIR_FIXTURE_PATH "${CMAKE_CURRENT_BINARY_DIR}/install-dir-fixture")
+set(INSTALL_DIR_FIXTURE_BIN_DIR "${INSTALL_DIR_FIXTURE_PATH}/bin/posix-${CMAKE_SYSTEM_PROCESSOR}")
+add_custom_command(
+    OUTPUT "${INSTALL_DIR_FIXTURE_BIN_DIR}/app.so"
+    COMMAND ${CMAKE_COMMAND} -E make_directory "${INSTALL_DIR_FIXTURE_BIN_DIR}"
+    COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:app_posix_module_test_fixture>" "${INSTALL_DIR_FIXTURE_BIN_DIR}/app.so"
+    DEPENDS app_posix_module_test_fixture
+)
+add_custom_target(install_dir_fixture DEPENDS "${INSTALL_DIR_FIXTURE_BIN_DIR}/app.so")
+
 file(GLOB_RECURSE TEST_SOURCES CONFIGURE_DEPENDS ${PROJECT_SOURCE_DIR}/source/*.cpp)
 add_executable(AppPosixModuleTests EXCLUDE_FROM_ALL ${TEST_SOURCES})
-add_dependencies(AppPosixModuleTests app_posix_module_test_fixture)
+add_dependencies(AppPosixModuleTests app_posix_module_test_fixture install_dir_fixture)
 
 target_include_directories(AppPosixModuleTests PRIVATE ${DOCTESTINC})
 target_compile_definitions(AppPosixModuleTests PRIVATE
     FIXTURE_APP_PATH="$<TARGET_FILE:app_posix_module_test_fixture>"
     FIXTURE_NON_ELF_PATH="${NON_ELF_FIXTURE_PATH}"
+    FIXTURE_INSTALL_DIR_PATH="${INSTALL_DIR_FIXTURE_PATH}"
 )
 
 add_test(NAME AppPosixModuleTests COMMAND AppPosixModuleTests)

Modules/app-posix-module/tests/source/loader_test.cpp

@@ -148,6 +148,12 @@ TEST_CASE("app_is_executable() rejects a nonexistent path") {
 TEST_CASE("app_is_executable() rejects an install-directory-shaped path missing its per-arch .so") {
     ensure_path_loader_registered();
 
-    // FIXTURE_DIR itself has no elf/posix-<arch>.so under it, so resolution fails.
+    // FIXTURE_DIR itself has no bin/posix-<arch>/app.so under it, so resolution fails.
     CHECK_FALSE(is_executable_path(FIXTURE_DIR.c_str()));
 }
+
+TEST_CASE("app_is_executable() accepts an install-directory-shaped path with bin/<arch>/app.so") {
+    ensure_path_loader_registered();
+
+    CHECK(is_executable_path(FIXTURE_INSTALL_DIR_PATH));
+}