os: dyn_linker: Add DynamicLinker (singleton) handling cross-platform dynamic libraries (WIP)

test_os_dynlinker passes on GNU/Linux, other platforms (esp Windows) must be tested.

For Windows we also would have other items to port, like jau::fs etc ..
in case no POSIX functions are available.

1 files changed, 98 insertions, 0 deletions

diff --git a/test/test_os_dynlinker.cpp b/test/test_os_dynlinker.cpp
new file mode 100644
index 0000000..cf86010
--- /dev/null
+++ b/test/test_os_dynlinker.cpp
@@ -0,0 +1,98 @@
+/*
+ * Author: Sven Gothel <[email protected]>
+ * Copyright (c) 2021 Gothel Software e.K.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <cassert>
+#include <cinttypes>
+#include <cstring>
+#include <memory>
+#include <thread>
+#include <pthread.h>
+
+#include <jau/test/catch2_ext.hpp>
+
+#include <jau/file_util.hpp>
+#include <jau/environment.hpp>
+#include <jau/os/dyn_linker.hpp>
+
+TEST_CASE( "Test 01 Global Open dlsym ..", "[dll][os]" ) {
+    {
+        std::string lib_path_var_name = jau::os::DynamicLinker::getEnvLibPathVarName();
+        std::string lib_path_var = jau::environment::getProperty( lib_path_var_name );
+        std::vector<std::string> lib_paths = jau::os::DynamicLinker::getSystemEnvLibraryPaths();
+        std::cout << "- lib_path_var_name: " << lib_path_var_name << std::endl;
+        std::cout << "- lib_path_var     : " << lib_path_var << std::endl;
+        std::cout << "- lib_paths: count " << lib_paths.size() << std::endl;
+        int i = 0;
+        for(const std::string& s : lib_paths) {
+            std::cout << "  - path[" << i << "]: " << s << std::endl;
+        }
+    }
+    const std::string libBasename = "jaulib";
+    const std::string symbolName = "jaulib_id_entryfunc";
+    const std::string libName = jau::os::DynamicLinker::getCanonicalName(libBasename);
+    std::cout << "- libBasename: " << libBasename << std::endl;
+    std::cout << "- libName: " << libName << std::endl;
+
+    std::string libPath;
+    {
+        std::cout << "- cwd: " << jau::fs::get_cwd() << std::endl;
+        std::cout << "- exe " << executable_path << std::endl << std::endl;
+
+        libPath = jau::fs::dirname(executable_path) + "/../src/"+libName;
+
+        jau::fs::file_stats path_stats(libPath);
+        std::cout << "fs: " << path_stats.to_string() << std::endl << std::endl;
+        if( !path_stats.exists() ) {
+            std::cout << "Warning: library '" << libName << "' doesn't exist at: '" << libPath << "'" << std::endl;
+            return;
+        }
+    }
+    jau::os::DynamicLinker& dl = jau::os::DynamicLinker::get();
+    jau::os::DynamicLinker::libhandle_t libHandle = dl.openLibraryGlobal(libPath);
+    std::cout << "- Path: " << libPath << std::endl;
+    std::cout << "- LibHandle: " << jau::to_hexstring(libHandle) << std::endl;
+    REQUIRE( 0 != libHandle );
+
+    jau::os::DynamicLinker::symhandle_t symHandle = dl.lookupSymbol(libHandle, symbolName);
+    std::cout << "- Symbol '" << symbolName << "': Handle = " << jau::to_hexstring(symHandle) << std::endl;
+    REQUIRE( 0 != symHandle );
+
+    const char* nativePath = dl.lookupLibraryPathname(libHandle, symbolName);
+    if( nullptr == nativePath ) {
+        std::cout << "- Native Path: null" << std::endl;
+    } else {
+        std::cout << "- Native Path: '" << std::string(nativePath) << "'" << std::endl;
+    }
+    REQUIRE( nullptr != nativePath );
+
+    {
+        std::string bname1 = jau::os::DynamicLinker::getBaseName(libPath);
+        std::cout << "- Basename (path): " << bname1 << std::endl;
+        REQUIRE( libBasename == bname1 );
+        if( nullptr != nativePath ) {
+            std::string bname2 = jau::os::DynamicLinker::getBaseName(std::string(nativePath));
+            std::cout << "- Basename (native-path): " << bname2 << std::endl;
+            REQUIRE( libBasename == bname2 );
+        }
+    }
+}