Initial commit of mpg123-1.29.3

src/compat/compat_dl.c

@@ -0,0 +1,108 @@
+/*
+	compat_dl: dynamic loading of shared libs
+
+	This is a separate libcompat to avoid needlessly linking all mpg123 code
+	with libdl on Unix.
+
+	copyright 2007-2019 by the mpg123 project - free software under the terms of the LGPL 2.1
+	see COPYING and AUTHORS files in distribution or http://mpg123.org
+	initially written by Thomas Orgis, Windows Unicode stuff by JonY.
+*/
+
+#include "config.h"
+/* This source file does need _POSIX_SOURCE to get some sigaction. */
+#define _POSIX_SOURCE
+#include "compat.h"
+
+#ifdef _MSC_VER
+#include <io.h>
+
+#if(defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_APP))
+#define WINDOWS_UWP
+#endif
+
+#endif
+#ifdef HAVE_SYS_STAT_H
+#  include <sys/stat.h>
+#endif
+#ifdef HAVE_DIRENT_H
+#  include <dirent.h>
+#endif
+
+/* Win32 is only supported with unicode now. These headers also cover
+   module stuff. The WANT_WIN32_UNICODE macro is synonymous with
+   "want windows-specific API, and only the unicode variants of which". */
+#ifdef WANT_WIN32_UNICODE
+#include <wchar.h>
+#include <windows.h>
+#include <winnls.h>
+#include <shlwapi.h>
+#endif
+
+#ifdef USE_MODULES
+#  ifdef HAVE_DLFCN_H
+#    include <dlfcn.h>
+#  endif
+#endif
+
+#include "debug.h"
+
+#include "wpathconv.h"
+
+#ifdef USE_MODULES
+/*
+	This is what I expected the platform-specific dance for dynamic module
+	support to be. Little did I know about the peculiarities of (long)
+	paths and directory/file search on Windows.
+
+	LoadLibrary throws GUI error boxes, use SetThreadErrorMode to suppress.
+	It needs to be done on per-thread basis to avoid race conditions
+	clobbering each other when setting/restoring across different threads.
+*/
+
+void *compat_dlopen(const char *path)
+{
+	void *handle = NULL;
+#ifdef WANT_WIN32_UNICODE
+	wchar_t *wpath;
+	wpath = u2wlongpath(path);
+	if(wpath) {
+		DWORD emode = GetThreadErrorMode();
+		int mode_ok = SetThreadErrorMode(emode | SEM_FAILCRITICALERRORS, NULL);
+		handle = LoadLibraryW(wpath);
+		if(mode_ok) {
+			SetThreadErrorMode(emode, NULL);
+		}
+	}
+	free(wpath);
+#else
+	handle = dlopen(path, RTLD_NOW);
+#endif
+	return handle;
+}
+
+void *compat_dlsym(void *handle, const char *name)
+{
+	void *sym = NULL;
+	if(!handle)
+		return NULL;
+#ifdef WANT_WIN32_UNICODE
+	sym = GetProcAddress(handle, name);
+#else
+	sym = dlsym(handle, name);
+#endif
+	return sym;
+}
+
+void compat_dlclose(void *handle)
+{
+	if(!handle)
+		return;
+#ifdef WANT_WIN32_UNICODE
+	FreeLibrary(handle);
+#else
+	dlclose(handle);
+#endif
+}
+
+#endif /* USE_MODULES */