From: Eric Biggers <ebiggers3@gmail.com>
Date: Sat, 9 Mar 2013 19:51:59 +0000 (-0600)
Subject: Support for making DLL correctly on Cygwin
X-Git-Tag: v1.3.0~42
X-Git-Url: https://wimlib.net/git/?p=wimlib;a=commitdiff_plain;h=c8b34bffb7884de559d6ac208e0bd982ea318a36

Support for making DLL correctly on Cygwin
---

diff --git a/Makefile.am b/Makefile.am
index 1e545bb1..9f455622 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,7 +7,7 @@ AM_CFLAGS	= -std=gnu99 -D_LARGEFILE_SOURCE \
 
 lib_LTLIBRARIES = libwim.la
 
-libwim_la_LDFLAGS = -version-info 4:0:2
+libwim_la_LDFLAGS = -version-info 4:0:2 $(CYGWIN_EXTRA_LDFLAGS)
 
 libwim_la_SOURCES =		\
 	src/add_image.c		\
@@ -86,7 +86,7 @@ libwim_la_LIBADD =		\
 
 libwim_la_CFLAGS =		\
 	$(AM_CFLAGS)		\
-	-fvisibility=hidden	\
+	$(VISIBILITY_CFLAGS)	\
 	$(LIBXML2_CFLAGS)	\
 	$(LIBFUSE_CFLAGS)	\
 	$(LIBNTFS_3G_CFLAGS)	\
diff --git a/configure.ac b/configure.ac
index 3b02ef84..c0c0f132 100644
--- a/configure.ac
+++ b/configure.ac
@@ -323,4 +323,22 @@ AC_SUBST([LIBCRYPTO_LDADD], [$LIBCRYPTO_LDADD])
 AC_SUBST([LIBCRYPTO_CFLAGS], [$LIBCRYPTO_CFLAGS])
 AC_SUBST([SHA1_SOURCES], [$SHA1_SOURCES])
 
+case "$host" in
+	*-*-cygwin*)
+		dnl -no-undefined is needed to build a DLL in a Cygwin environment.
+		CYGWIN_EXTRA_LDFLAGS="-no-undefined"
+
+		dnl -fvisibility=hidden should not be used in a Cygwin
+		dnl  environment
+		VISIBILITY_CFLAGS=""
+		;;
+	*)
+		CYGWIN_EXTRA_LDFLAGS=""
+		VISIBILITY_CFLAGS="-fvisibility=hidden"
+		;;
+esac
+
+AC_SUBST([CYGWIN_EXTRA_LDFLAGS], [$CYGWIN_EXTRA_LDFLAGS])
+AC_SUBST([VISIBILITY_CFLAGS], [$VISIBILITY_CFLAGS])
+
 AC_OUTPUT
diff --git a/src/util.h b/src/util.h
index 4f405666..b79490e8 100644
--- a/src/util.h
+++ b/src/util.h
@@ -9,7 +9,11 @@
 #include "config.h"
 
 #ifdef __GNUC__
-#	define WIMLIBAPI __attribute__((visibility("default")))
+#	if defined(__CYGWIN__) || defined(__WIN32__)
+#		define WIMLIBAPI __declspec(dllexport)
+#	else
+#		define WIMLIBAPI __attribute__((visibility("default")))
+#	endif
 #	define ALWAYS_INLINE inline __attribute__((always_inline))
 #	define PACKED __attribute__((packed))
 #	define FORMAT(type, format_str, args_start) \