From 8e0b1b22982de8467f0d1e9af5fdd13972828a4f Mon Sep 17 00:00:00 2001
From: Dnomd343 <dnomd343@gmail.com>
Date: Sun, 24 Mar 2024 21:54:38 +0800
Subject: [PATCH] feat: build dynamic library

---
 CMakeLists.txt | 43 ++++++++++++++++++++++++++++++++++---------
 src/md5.h      |  8 +++++---
 2 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 93faaa5..50609c4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,42 +1,67 @@
 cmake_minimum_required(VERSION 3.12)
 project(md5sum LANGUAGES CXX)
 
+# ------------------------------------------------------------------------------------ #
+
+option(MD5_SHARED_LIB "Built as a dynamic library." OFF)
 option(MD5_ENABLE_TESTING "Enable testing of the md5sum library." ON)
 option(MD5_ENABLE_BENCHMARK "Enable benchmark of the md5sum library." ON)
 
+# ------------------------------------------------------------------------------------ #
+
 set(CXX_STANDARDS)
 foreach (CXX_FEATURE ${CMAKE_CXX_COMPILE_FEATURES})
     if (CXX_FEATURE MATCHES "^cxx_std_[0-9]+$")
         string(REGEX MATCH "[0-9]+$" CXX_STANDARD ${CXX_FEATURE})
-        list(APPEND CXX_STANDARDS ${CXX_STANDARD})  # Get supported c++ standards
+        list(APPEND CXX_STANDARDS ${CXX_STANDARD})  # supported c++ standards
     endif()
 endforeach()
 
 if (NOT 17 IN_LIST CXX_STANDARDS)
-    message(FATAL_ERROR "MD5 projects require at least C++17 support.")
+    message(FATAL_ERROR "MD5 project require at least C++17.")
 endif()
 
-list(GET CXX_STANDARDS -1 MD5_CXX_STANDARD)  # Select the latest C++ standard
+list(GET CXX_STANDARDS -1 MD5_CXX_STANDARD)  # select the latest C++ standard
 message(STATUS "MD5 CXX Standard: ${MD5_CXX_STANDARD}")
 set(CMAKE_CXX_STANDARD ${MD5_CXX_STANDARD})
+
+# ------------------------------------------------------------------------------------ #
+
+if (NOT CMAKE_BUILD_TYPE)
+    set(CMAKE_BUILD_TYPE Release)  # using release build in default
+endif()
 add_compile_options(-Wall -Wextra)
 
-add_library(md5sum STATIC src/impl/core.cc src/impl/wrapper.cc)
-target_compile_options(md5sum PRIVATE -fno-rtti -fno-exceptions)
+file(GLOB MD5_SRC src/impl/*.cc)
+if (NOT MD5_SHARED_LIB)
+    add_library(md5sum STATIC ${MD5_SRC})
+else()
+    add_library(md5sum SHARED ${MD5_SRC})
+    target_compile_options(md5sum PRIVATE -fvisibility=hidden)
+endif()
 target_include_directories(md5sum PUBLIC src/)
 
-include(third_party/ThirdParty.cmake)
+set(MD5_COMPILE_OPTIONS -fno-rtti -fno-exceptions -pedantic)
+target_compile_options(md5sum PRIVATE ${MD5_COMPILE_OPTIONS})
+
 add_library(md5sum::md5sum ALIAS md5sum)
 
+# ------------------------------------------------------------------------------------ #
+
+include(third_party/ThirdParty.cmake)
+
 if (MD5_ENABLE_TESTING)
     enable_testing()
-    add_executable(md5_test test/hash.cc test/assert.cc test/simple.cc test/stream.cc)
-    target_link_libraries(md5_test PRIVATE md5sum::md5sum GTest::gtest_main)
+    file(GLOB MD5_TEST_SRC test/*.cc)
+    add_executable(md5_test ${MD5_TEST_SRC})
+    target_link_libraries(md5_test PRIVATE md5sum GTest::gtest_main)
     add_test(NAME md5_test COMMAND md5_test)
 endif()
 
 if (MD5_ENABLE_BENCHMARK)
     add_executable(md5_benchmark benchmark.cc)
-    target_link_libraries(md5_benchmark PRIVATE md5sum::md5sum benchmark::benchmark_main)
+    target_link_libraries(md5_benchmark PRIVATE md5sum benchmark::benchmark_main)
     target_compile_options(md5_benchmark PRIVATE -fno-rtti -fno-exceptions)
 endif()
+
+# ------------------------------------------------------------------------------------ #
diff --git a/src/md5.h b/src/md5.h
index 5a40be1..fc8d707 100644
--- a/src/md5.h
+++ b/src/md5.h
@@ -10,6 +10,8 @@ static_assert(sizeof(uintptr_t) == 8,
 static_assert(__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__,
     "Project only works on little-endian architecture.");
 
+#define MD5_EXPORT __attribute__ ((visibility ("default")))
+
 #include "impl/value.inc"
 #include "impl/constexpr.inc"
 
@@ -26,13 +28,13 @@ public:
     MD5& Update(const std::string_view &data);
 
     /// Update md5 hash with specified data.
-    MD5& Update(const void *data, uint64_t len);
+    MD5_EXPORT MD5& Update(const void *data, uint64_t len);
 
     /// Stop streaming updates and calculate result.
     MD5& Final();
 
     /// Get the string result of md5.
-    [[nodiscard]] std::string Digest() const;
+    [[nodiscard]] MD5_EXPORT std::string Digest() const;
 
     /// Calculate the md5 hash value of the specified data.
     static std::string Hash(const std::string_view &data);
@@ -63,7 +65,7 @@ private:
     const void* UpdateImpl(const void *data, uint64_t len);
 
     /// Update and final the md5 hash with the specified data.
-    void FinalImpl(const void *data, uint64_t len);
+    MD5_EXPORT void FinalImpl(const void *data, uint64_t len);
 };
 
 } // namespace md5