Basic support for building with Cygwin and MinGW using

the Autotools based build system. It's not good yet, more
fixes will follow.

configure.ac

@@ -427,7 +427,14 @@ echo
 echo "Initializing Libtool:"
 CXX=no
 F77=no
+AC_LIBTOOL_WIN32_DLL
 AC_PROG_LIBTOOL
+AC_LIBTOOL_RC
+
+dnl Some day we can drop support for libtool 1.5.x. Then the above five
+dnl lines can be replaced with these:
+dnl LT_INIT([win32-dll])
+dnl LT_LANG([Windows Resource])
 
 
 ###############################################################################

src/liblzma/api/lzma.h

@@ -173,9 +173,12 @@
  * to operating systems like Windows, or at least don't care about linking
  * against static liblzma on them, don't worry about LZMA_API_STATIC. That
  * is, most developers will never need to use LZMA_API_STATIC.
+ *
+ * Cygwin is a special case on Windows. We rely on GCC doing the right thing
+ * and thus don't use dllimport and don't specify the calling convention.
  */
 #ifndef LZMA_API_IMPORT
-#	if !defined(LZMA_API_STATIC) && defined(_WIN32)
+#	if !defined(LZMA_API_STATIC) && defined(_WIN32) && !defined(__CYGWIN__)
 #		define LZMA_API_IMPORT __declspec(dllimport)
 #	else
 #		define LZMA_API_IMPORT
@@ -183,7 +186,7 @@
 #endif
 
 #ifndef LZMA_API_CALL
-#	ifdef _WIN32
+#	if defined(_WIN32) && !defined(__CYGWIN__)
 #		define LZMA_API_CALL __cdecl
 #	else
 #		define LZMA_API_CALL

src/liblzma/check/crc32_x86.S

@@ -76,7 +76,8 @@ init_table(void)
 	.text
 	.globl	LZMA_CRC32
 
-#if !defined(__MACH__) && !defined(_WIN32) && !defined(__MSDOS__)
+#if !defined(__MACH__) && !defined(_WIN32) && !defined(__CYGWIN__) \
+		&& !defined(__MSDOS__)
 	.type	LZMA_CRC32, @function
 #endif
 
@@ -275,8 +276,8 @@ LZMA_CRC32:
 	.indirect_symbol LZMA_CRC32_TABLE
 	.long 0
 
-#elif defined(_WIN32)
+#elif defined(_WIN32) || defined(__CYGWIN__)
-#	ifndef LZMA_API_STATIC
+#	ifdef DLL_EXPORT
 	/* This is equivalent of __declspec(dllexport). */
 	.section .drectve
 	.ascii " -export:lzma_crc32"

src/liblzma/check/crc64_x86.S

@@ -66,7 +66,8 @@ init_table(void)
 	.text
 	.globl	LZMA_CRC64
 
-#if !defined(__MACH__) && !defined(_WIN32) && !defined(__MSDOS__)
+#if !defined(__MACH__) && !defined(_WIN32) && !defined(__CYGWIN__) \
+		&& !defined(__MSDOS__)
 	.type	LZMA_CRC64, @function
 #endif
 
@@ -258,8 +259,8 @@ LZMA_CRC64:
 	.indirect_symbol LZMA_CRC64_TABLE
 	.long 0
 
-#elif defined(_WIN32)
+#elif defined(_WIN32) || defined(__CYGWIN__)
-#	ifndef LZMA_API_STATIC
+#	ifdef DLL_EXPORT
 	/* This is equivalent of __declspec(dllexport). */
 	.section .drectve
 	.ascii " -export:lzma_crc64"

src/liblzma/common/common.h

@@ -17,7 +17,7 @@
 #include "../../common/mythread.h"
 #include "../../common/integer.h"
 
-#if !defined(LZMA_API_STATIC) && defined(_WIN32)
+#if defined(DLL_EXPORT) && (defined(_WIN32) || defined(__CYGWIN__))
 #	define LZMA_API_EXPORT __declspec(dllexport)
 // Don't use ifdef or defined() below.
 #elif HAVE_VISIBILITY

windows/Makefile

@@ -62,8 +62,6 @@ ALL_CPPFLAGS = \
 
 ALL_CPPFLAGS += -DHAVE_CONFIG_H
 
-STATIC_CPPFLAGS = -DLZMA_API_STATIC
-
 # This works with Wine too while using native GNU make, sed, and rm.
 ifdef WINE
 ifdef W64
@@ -213,10 +211,10 @@ liblzma.dll: $(LIBLZMA_OBJS)
 	$(STRIP) --strip-all liblzma.dll
 
 $(LIBLZMA_OBJS_C): %.o: %.c
-	$(CC) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
+	$(CC) -DDLL_EXPORT $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
 
 $(LIBLZMA_OBJS_ASM): %.o: %.S
-	$(CC) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
+	$(CC) -DDLL_EXPORT $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
 
 liblzma_static.lib: $(LIBLZMA_OBJS_STATIC)
 	$(RM) $@
@@ -224,10 +222,10 @@ liblzma_static.lib: $(LIBLZMA_OBJS_STATIC)
 	$(STRIP) --strip-unneeded $@
 
 $(LIBLZMA_OBJS_STATIC_C): %-static.o: %.c
-	$(CC) $(STATIC_CPPFLAGS) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
+	$(CC) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
 
 $(LIBLZMA_OBJS_STATIC_ASM): %-static.o: %.S
-	$(CC) $(STATIC_CPPFLAGS) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
+	$(CC) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
 
 .PHONY: liblzma-clean
 liblzma-clean:
@@ -252,11 +250,11 @@ lzmadec-dynamic.exe: liblzma.dll $(XZDEC_SRCS) lzmadec_rc.o
 	$(STRIP) --strip-all $@
 
 xzdec.exe: liblzma_static.lib $(XZDEC_SRCS) xzdec_rc.o
-	$(CC) $(STATIC_CPPFLAGS) $(ALL_CPPFLAGS) $(ALL_CFLAGS) $(XZDEC_SRCS) xzdec_rc.o -o $@ liblzma_static.lib
+	$(CC) -DLZMA_API_STATIC $(ALL_CPPFLAGS) $(ALL_CFLAGS) $(XZDEC_SRCS) xzdec_rc.o -o $@ liblzma_static.lib
 	$(STRIP) --strip-all $@
 
 lzmadec.exe: liblzma_static.lib $(XZDEC_SRCS) lzmadec_rc.o
-	$(CC) $(STATIC_CPPFLAGS) $(ALL_CPPFLAGS) -DLZMADEC $(ALL_CFLAGS) $(XZDEC_SRCS) lzmadec_rc.o -o $@ liblzma_static.lib
+	$(CC) -DLZMA_API_STATIC $(ALL_CPPFLAGS) -DLZMADEC $(ALL_CFLAGS) $(XZDEC_SRCS) lzmadec_rc.o -o $@ liblzma_static.lib
 	$(STRIP) --strip-all $@
 
 .PHONY: xzdec-clean
@@ -301,7 +299,7 @@ xz-dynamic.exe: liblzma.dll $(XZ_OBJS) xz_rc.o
 	$(STRIP) --strip-all $@
 
 $(XZ_OBJS_STATIC): %-static.o: %-fixed.c
-	$(CC) $(STATIC_CPPFLAGS) $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
+	$(CC) -DLZMA_API_STATIC $(ALL_CPPFLAGS) $(ALL_CFLAGS) -c -o $@ $<
 
 xz.exe: liblzma_static.lib $(XZ_OBJS_STATIC) xz_rc.o
 	$(CC) $(ALL_CFLAGS) $(XZ_OBJS_STATIC) xz_rc.o -o $@ liblzma_static.lib