From 9d783a6df723fbbe221a5b77412a3418fdffbaeb Mon Sep 17 00:00:00 2001
From: ruki <waruqi@gmail.com>
Date: Sun, 3 May 2020 20:42:29 +0800
Subject: [PATCH] improve to detect elf arch

---
 src/lni/main.cpp | 40 ++++++++++++++++++++++++++++++++++++++++
 src/lua/main.lua | 19 ++++++++++++-------
 2 files changed, 52 insertions(+), 7 deletions(-)

diff --git a/src/lni/main.cpp b/src/lni/main.cpp
index df07a53..7417236 100644
--- a/src/lni/main.cpp
+++ b/src/lni/main.cpp
@@ -100,6 +100,45 @@ static tb_int_t lni_elf_add_libraries(lua_State* lua)
     return 1;
 }
 
+// elf.detect_arch("libx.so")
+static tb_int_t lni_elf_detect_arch(lua_State* lua)
+{
+    try 
+    {
+        // get arguments
+        tb_char_t const* inputfile = luaL_checkstring(lua, 1);
+        if (!inputfile) throw "invalid arguments!";
+
+        // get arch
+        auto elf_binary = std::unique_ptr<LIEF::ELF::Binary>{LIEF::ELF::Parser::parse(inputfile)};
+        switch (elf_binary->header().machine_type())
+        {
+        case LIEF::ELF::ARCH::EM_AARCH64:
+            lua_pushliteral(lua, "arm64-v8a");
+            break;
+        case LIEF::ELF::ARCH::EM_ARM:
+            lua_pushliteral(lua, "armeabi-v7a");
+            break;
+        case LIEF::ELF::ARCH::EM_X86_64:
+            lua_pushliteral(lua, "x86_64");
+            break;
+        case LIEF::ELF::ARCH::EM_386:
+            lua_pushliteral(lua, "x86");
+            break;
+        default:
+            lua_pushliteral(lua, "armeabi");
+            break;
+        }
+    }
+    catch (std::exception const& e) 
+    {
+        lua_pushnil(lua);
+        lua_pushstring(lua, e.what());
+        return 2;
+    }
+    return 1;
+}
+
 // macho.add_libraries("libx.so", {"liba.dylib", "libb.dylib"})
 static tb_int_t lni_macho_add_libraries(lua_State* lua)
 {
@@ -154,6 +193,7 @@ static tb_void_t lni_initalizer(xm_engine_ref_t engine, lua_State* lua)
     static luaL_Reg const lni_elf_funcs[] = 
     {
         {"add_libraries", lni_elf_add_libraries}
+    ,   {"detect_arch",   lni_elf_detect_arch}
     ,   {tb_null, tb_null}
     };
     xm_engine_register(engine, "elf", lni_elf_funcs);
diff --git a/src/lua/main.lua b/src/lua/main.lua
index 020b751..ecfa0f1 100644
--- a/src/lua/main.lua
+++ b/src/lua/main.lua
@@ -155,15 +155,20 @@ function _inject_apk(inputfile, outputfile, libraries)
         raise("extract failed!")
     end
 
+    -- detect architecture
+    local arch
+    for _, library in ipairs(libraries) do
+        arch = os.isfile(library) and elf.detect_arch(library)
+        if arch then
+            break
+        end
+    end
+    arch = arch or "armeabi-v7a"
+    print("%s found!", arch)
+
     -- remove META-INF
     os.tryrm(path.join(tmpdir, "META-INF"))
 
-    -- get arch and library directory
-    local arch = "armeabi-v7a"
-    local result = try {function () return os.iorunv("file", {inputfile}) end}
-    if result and result:find("aarch64", 1, true) then
-        arch = "arm64-v8a"
-    end
     local libdir = path.join(tmpdir, "lib", arch)
     if not os.isdir(libdir) then
         arch = "armeabi"
@@ -177,7 +182,7 @@ function _inject_apk(inputfile, outputfile, libraries)
         table.insert(libnames, path.filename(library))
     end
     for _, libfile in ipairs(os.files(path.join(libdir, (option.get("pattern") or "*") .. ".so"))) do
-        print("inject to %s", path.filename(libfile))
+        print("inject to %s/%s", path.filename(path.directory(libfile)), path.filename(libfile))
         elf.add_libraries(libfile, libfile, libnames)
     end