Add shims for hidden API

Author: iscle

CMakeLists.txt

@@ -7,13 +7,13 @@ add_compile_definitions(VIPER_VERSION=20240314)
 
 # External
 set(CORE_SRC
-        external/core/libcutils/ashmem-host.cpp
+        #[[external/core/libcutils/ashmem-host.cpp
         external/core/libcutils/native_handle.cpp
         external/core/libutils/SystemClock.cpp
-        external/core/libutils/Timers.cpp)
+        external/core/libutils/Timers.cpp]])
 
 set(LIBFMQ_SRC
-        external/libfmq/EventFlag.cpp)
+        #[[external/libfmq/EventFlag.cpp]])
 
 include_directories(
         external/libbase/include
@@ -223,5 +223,6 @@ add_library(v4a_re SHARED
         ${FILES})
 
 target_link_libraries(v4a_re log binder_ndk) # kissfft)
+target_link_options(v4a_re PRIVATE "LINKER:--no-demangle")
 target_compile_options(v4a_re PRIVATE -flto -O3 -DNDEBUG)
 #target_compile_options(v4afx_r PRIVATE -O2 -DNDEBUG -Wall -Wsign-conversion -Wno-unused-result -Wno-unneeded-internal-declaration -fstrict-aliasing -fvisibility=hidden -Wextra -Wno-unused-parameter)

src/shim.cpp

@@ -1,20 +1,79 @@
-#include <string>
+/**
+ * Shims for the "hidden" api, not found in the Android NDK.
+ *
+ * The symbols are compiled with the NDK, but the real Android ones have
+ * a slightly different mangled name.
+*/
+
 #include <log/log.h>
+#include <dlfcn.h>
+
+// libcutils
+void *ashmem_create_region;
+void *ashmem_set_prot_region;
+void *native_handle_create;
+void *native_handle_delete;
+void *native_handle_close;
+
+// libfmq
+void *_ZN7android8hardware7details5checkEbPKc;
+void *_ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE; // ndk
+void *_ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_; // ndk
+void *_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_;
 
-namespace android::hardware::details {
-    void check(bool exp) {
-        ALOGE_IF(!exp, "Check failed");
+static void init_libcutils() {
+    void *libcutils = dlopen("libcutils.so", RTLD_NOW);
+    if (libcutils == nullptr) {
+        ALOGE("Failed to load libcutils.so");
+        return;
     }
 
-    void check(bool exp, const char* message) {
-        ALOGE_IF(!exp, "%s", message);
+    ashmem_create_region = dlsym(libcutils, "ashmem_create_region");
+    ashmem_set_prot_region = dlsym(libcutils, "ashmem_set_prot_region");
+
+    native_handle_create = dlsym(libcutils, "native_handle_create");
+    native_handle_close = dlsym(libcutils, "native_handle_close");
+    native_handle_delete = dlsym(libcutils, "native_handle_delete");
+
+    if (ashmem_create_region == nullptr ||
+        ashmem_set_prot_region == nullptr ||
+        native_handle_create == nullptr ||
+        native_handle_close == nullptr ||
+        native_handle_delete == nullptr) {
+        ALOGE("Failed to load symbols from libcutils.so");
     }
 
-    void logError(const std::string &message) {
-        ALOGE("%s", message.c_str());
+    dlclose(libcutils);
+}
+
+static void init_libfmq() {
+    void *libfmq = dlopen("libfmq.so", RTLD_NOW);
+    if (libfmq == nullptr) {
+        ALOGE("Failed to load libfmq.so");
+        return;
     }
 
-    void errorWriteLog(int tag, const char* info) {
-        ALOGE("%d: %s", tag, info);
+    _ZN7android8hardware7details5checkEbPKc = dlsym(libfmq, "_ZN7android8hardware7details5checkEbPKc");
+    // ndk variant, real symbol: _ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE
+    _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE = dlsym(libfmq, "_ZN7android8hardware7details8logErrorERKNSt3__112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE");
+    // ndk variant, real symbol: _ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_
+    _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15createEventFlagEPNSt3__16atomicIjEEPPS1_");
+    _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ = dlsym(libfmq, "_ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_");
+
+    if (_ZN7android8hardware7details5checkEbPKc == nullptr ||
+        _ZN7android8hardware7details8logErrorERKNSt6__ndk112basic_stringIcNS2_11char_traitsIcEENS2_9allocatorIcEEEE == nullptr ||
+        _ZN7android8hardware9EventFlag15createEventFlagEPNSt6__ndk16atomicIjEEPPS1_ == nullptr ||
+        _ZN7android8hardware9EventFlag15deleteEventFlagEPPS1_ == nullptr) {
+        ALOGE("Failed to load symbols from libfmq.so");
     }
-} // namespace android::hardware::details
+
+    dlclose(libfmq);
+}
+
+__attribute__((constructor))
+void shim_init() {
+    ALOGD("shim_init");
+    init_libcutils();
+    init_libfmq();
+    ALOGD("shim_init done");
+}

src/viper_aidl.cpp

@@ -238,8 +238,11 @@ ndk::ScopedAStatus ViPER4AndroidAIDL::command(CommandId id) {
             stopThread();
             break;
         }
+        default:
+            ALOGE("command: unknown command %d", static_cast<int>(id));
+            return ndk::ScopedAStatus::fromExceptionCode(EX_ILLEGAL_ARGUMENT);
     }
-    return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    return ndk::ScopedAStatus::ok();
 }
 
 ndk::ScopedAStatus ViPER4AndroidAIDL::getState(State *state) {