Add function dladdr() and associated test application test-dladdr

2 files changed, 192 insertions, 0 deletions

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 5fc6c44..f0871e5 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -9,9 +9,17 @@ target_link_libraries(testdll2 dl)
 
 add_library(testdll3 SHARED testdll3.c)
 set_target_properties(testdll3 PROPERTIES PREFIX "")
+add_executable(test-dladdr test-dladdr.c)
+target_link_libraries(test-dladdr dl)
+if(UNIX)
+    set_target_properties(test-dladdr PROPERTIES COMPILE_FLAGS "-Wl,--export-dynamic -fpie")
+endif()
+
+install(TARGETS test-dladdr EXPORT dlfcn-win32-targets RUNTIME DESTINATION bin)
 
 add_executable(t_dlfcn test.c)
 target_link_libraries(t_dlfcn dl)
 if(RUN_TESTS)
     add_test(NAME t_dlfcn COMMAND ${WRAPPER} $<TARGET_FILE:t_dlfcn> WORKING_DIRECTORY $<TARGET_FILE_DIR:t_dlfcn>)
+    add_test(NAME test-dladdr COMMAND ${WRAPPER} $<TARGET_FILE:test-dladdr> WORKING_DIRECTORY $<TARGET_FILE_DIR:test-dladdr>)
 endif()
diff --git a/tests/test-dladdr.c b/tests/test-dladdr.c
new file mode 100644
index 0000000..57914cb
--- /dev/null
+++ b/tests/test-dladdr.c
@@ -0,0 +1,184 @@
+/* On Unix like os compile with "-Wl,--export-dynamic -fpie" (default with cmake) */
+
+/* required for non Windows builds, must be set in front of the first system include */
+#define _GNU_SOURCE
+
+#include <dlfcn.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static int verbose = 0;
+
+typedef enum {
+    Pass = 1,
+    PassWithoutSymbol = 2,
+    PassWithDifferentAddress = 3,
+    Fail = 0,
+    NoInfo = -1,
+} ExpectedResult;
+
+typedef void (* func) (void);
+
+static void print_dl_info( Dl_info *info, char *prefix, char *suffix )
+{
+    printf( "%sfilename: %s base: %p symbol name: '%s' addr: %p%s", prefix, info->dli_fname, info->dli_fbase, info->dli_sname, info->dli_saddr, suffix );
+}
+
+/**
+ * @brief check information returned by dladdr
+ * @param hint text describing what to test
+ * @param addr address to check
+ * @param addrsym
+ * @param expected check against expected result
+ * @return 0 check passed
+ * @return 1 check failed
+ */
+static int check_dladdr( const char *hint, void *addr, char *addrsym, ExpectedResult expected_result )
+{
+    Dl_info info;
+    int result = dladdr( addr, &info );
+    int passed = 0;
+    if (!result)
+    {
+        passed = expected_result == NoInfo || expected_result == Fail;
+    }
+    else
+    {
+        int sym_match  = info.dli_sname && strcmp( addrsym, info.dli_sname ) == 0;
+        int addr_match  = addr == info.dli_saddr;
+        passed = (expected_result == Pass && sym_match && addr_match)
+                 || (expected_result == PassWithoutSymbol && addr_match && !info.dli_sname)
+                 || (expected_result == PassWithDifferentAddress && sym_match && !addr_match)
+                 || (expected_result == Fail && (!sym_match || !addr_match));
+    }
+    printf( "checking '%s' - address %p which should have symbol '%s' -> %s%s", hint, addr, addrsym, passed ? "passed" : "failed", verbose || !passed ? " " : "\n" );
+    if( verbose || !passed )
+    {
+        if( !result )
+            printf( "(could not get symbol information for address %p)\n", addr );
+        else
+            print_dl_info( &info, "(", ")\n");
+    }
+    return !passed;
+}
+
+#ifdef _WIN32
+/**
+ * @brief check address from a symbol located in a shared lilbrary
+ * @param hint text describing what to test
+ * @param libname libray to get the address from
+ * @param addrsym symbol to get the address for
+ * @param should_match result should match the given values
+ * @return 0 check passed
+ * @return 1 check failed
+ * @return 2 failed to open library
+ * @return 3 failed to get symbol address
+ */
+static int check_dladdr_by_dlopen( const char *hint, char *libname, char *sym, int should_match )
+{
+    void *library = NULL;
+    void *addr = NULL;
+    int result;
+
+    library = dlopen( libname, RTLD_GLOBAL );
+    if ( library == NULL )
+    {
+        fprintf( stderr, "could not open '%s'\n", libname );
+        return 2;
+    }
+
+    addr = dlsym( library, sym );
+    if ( !addr ) {
+        fprintf( stderr, "could not get address from library '%s' for symbol '%s'\n", libname, sym );
+        return 3;
+    }
+
+    result = check_dladdr( hint, addr, sym, should_match );
+    dlclose( library );
+
+    return result;
+}
+#endif
+
+#ifdef _WIN32
+#include <windows.h>
+#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
+/* hide warning "reclared without 'dllimport' attribute" */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wattributes"
+#elif defined(_MSC_VER)
+/* disable warning C4273 inconsistent dll linkage */
+#pragma warning(push)
+#pragma warning(disable: 4273)
+#endif
+/*
+ * Windows API functions decorated with WINBASEAPI are imported from iat.
+ * For testing force linking by import thunk for the following functions
+ */
+HMODULE WINAPI GetModuleHandleA (LPCSTR lpModuleName);
+SIZE_T WINAPI VirtualQuery (LPCVOID lpAddress, PMEMORY_BASIC_INFORMATION lpBuffer, SIZE_T dwLength);
+/* force linking by iat */
+/* WINBASEAPI, which is normally used here, can be overriden by compiler or application, so we cannot use it */
+__declspec(dllimport) HMODULE WINAPI LoadLibraryExA(LPCSTR lpLibFileName, HANDLE hFile, DWORD  dwFlags);
+__declspec(dllimport) int __cdecl atoi(const char *_Str);
+
+#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))
+#pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+#pragma warning(pop)
+#endif
+#endif
+
+#ifdef _WIN32
+#define FailOnWin Fail
+#else
+#define FailOnWin Pass
+#endif
+
+#if defined(_WIN32) && !defined(DLFCN_WIN32_SHARED)
+#define PassOnSharedBuild Fail
+#else
+#define PassOnSharedBuild Pass
+#endif
+
+#define UNUSED(x) (void)x
+
+int main(int argc, char **argv)
+{
+    /* points to non reachable address */
+    unsigned char zero_thunk_address[6] = { 0xFF, 0x25, 0x00, 0x00, 0x00, 0x00 };
+    /* points to executable base */
+    unsigned char invalid_thunk_address[6] = { 0xFF, 0x25, 0x00, 0x00, 0x40, 0x00 };
+    /* no import thunk */
+    unsigned char no_import_thunk[6] = { 0xFF, 0x26, 0x00, 0x00, 0x40, 0x00 };
+    int  result = 0;
+    UNUSED(argv);
+
+    if (argc == 2)
+        verbose = 1;
+
+    result = check_dladdr( "null pointer", (void*)0, NULL , NoInfo);
+    result |= check_dladdr( "invalid pointer", (void*)0x125, NULL , NoInfo);
+    result |= check_dladdr( "function from dl library", (void*)dladdr, "dladdr" , PassOnSharedBuild );
+    result |= check_dladdr( "function from dl library", (void*)dlopen, "dlopen", PassOnSharedBuild );
+    result |= check_dladdr( "function from glibc/msvcrt library", (void*)atoi, "atoi", Pass );
+    result |= check_dladdr( "function from executable", (void*)main, "main", FailOnWin );
+    result |= check_dladdr( "static function from executable", (void*)print_dl_info, "print_dl_info", Fail );
+    result |= check_dladdr( "address with positive offset", ((char*)atoi)+1, "atoi", PassWithDifferentAddress );
+    result |= check_dladdr( "zero address from import thunk", zero_thunk_address, "", NoInfo );
+    result |= check_dladdr( "invalid address from import thunk", invalid_thunk_address, "", NoInfo );
+    result |= check_dladdr( "no import thunk", no_import_thunk, "", NoInfo );
+
+#ifdef _WIN32
+    result |= check_dladdr( "last entry in iat", (void*)VirtualQuery, "VirtualQuery", PassWithDifferentAddress );
+
+    result |= check_dladdr ( "address through import thunk", (void*)GetModuleHandleA, "GetModuleHandleA", PassWithDifferentAddress );
+    result |= check_dladdr_by_dlopen( "address by dlsym", "kernel32.dll", "GetModuleHandleA", Pass );
+
+    result |= check_dladdr ( "address by image allocation table", (void*)LoadLibraryExA, "LoadLibraryExA", Pass );
+    result |= check_dladdr_by_dlopen( "address by dlsym", "kernel32.dll", "LoadLibraryExA", Pass );
+#endif
+    return result;
+}