File 0001-cmake-Fix-pkgconfig-support-on-Windows.patch of Package mingw32-zlib

From 4debfd7393379f83bf5ecf4afa2f39bef76abee9 Mon Sep 17 00:00:00 2001
From: Ralf Habacker <ralf.habacker@freenet.de>
Date: Sun, 5 May 2019 16:48:49 +0200
Subject: [PATCH] cmake: Fix pkgconfig support on Windows

1. Add cpp macro ZLIB_DLL to zlib.pc, which is required to link
   to the shared library
2. Install zlib-static.pc for usage of the static library
3  Let library names follow mingw style,which is the same as on unix
  (libz.a/libz.dll.a)
---
 CMakeLists.txt  | 34 +++++++++++++++++++++++++++-------
 zlib.pc.cmakein |  4 ++--
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0fe939d..5d0363a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -78,9 +78,6 @@ if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
   endif()
 endif()
 
-set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
-configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
-		${ZLIB_PC} @ONLY)
 configure_file(	${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.cmakein
 		${CMAKE_CURRENT_BINARY_DIR}/zconf.h @ONLY)
 include_directories(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_SOURCE_DIR})
@@ -205,11 +202,34 @@ if(UNIX)
    if(NOT APPLE)
      set_target_properties(zlib PROPERTIES LINK_FLAGS "-Wl,--version-script,\"${CMAKE_CURRENT_SOURCE_DIR}/zlib.map\"")
    endif()
-elseif(BUILD_SHARED_LIBS AND WIN32)
-    # Creates zlib1.dll when building shared library version
-    set_target_properties(zlib PROPERTIES SUFFIX "1.dll")
+elseif(WIN32)
+    # on windows the static library is always called <compiler-prefix>z
+    set_target_properties(zlibstatic PROPERTIES OUTPUT_NAME z)
+    if(BUILD_SHARED_LIBS AND MSVC)
+        # Creates zlib1.dll when building shared library version
+        set_target_properties(zlib PROPERTIES SUFFIX "1.dll")
+    else()
+        # on windows the shared library is always called <compiler-prefix>z
+        set_target_properties(zlib PROPERTIES OUTPUT_NAME z)
+    endif()
 endif()
 
+# in the static library pc file we use the whole filename
+# to avoid fetching the shared import library name
+set(ZLIB_PC_STATIC ${CMAKE_CURRENT_BINARY_DIR}/zlib-static.pc)
+get_target_property(static_location zlibstatic LOCATION)
+get_filename_component(filename ${static_location} NAME)
+set(PC_LIBS "-Wl,\${libdir}/${filename}")
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
+               ${ZLIB_PC_STATIC} @ONLY)
+
+# in the shared library pc file we use the regular library name
+set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
+set(PC_LIBS "-L\${libdir} -L\${sharedlibdir} -lz")
+set(PC_CFLAGS -DZLIB_DLL)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
+               ${ZLIB_PC} @ONLY)
+
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
     install(TARGETS zlib zlibstatic
         RUNTIME DESTINATION "${INSTALL_BIN_DIR}"
@@ -223,7 +243,7 @@ if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
     install(FILES zlib.3 DESTINATION "${INSTALL_MAN_DIR}/man3")
 endif()
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
-    install(FILES ${ZLIB_PC} DESTINATION "${INSTALL_PKGCONFIG_DIR}")
+    install(FILES ${ZLIB_PC} ${ZLIB_PC_STATIC} DESTINATION "${INSTALL_PKGCONFIG_DIR}")
 endif()
 
 #============================================================================
diff --git a/zlib.pc.cmakein b/zlib.pc.cmakein
index a5e6429..916c109 100644
--- a/zlib.pc.cmakein
+++ b/zlib.pc.cmakein
@@ -9,5 +9,5 @@ Description: zlib compression library
 Version: @VERSION@
 
 Requires:
-Libs: -L${libdir} -L${sharedlibdir} -lz
-Cflags: -I${includedir}
+Libs: @PC_LIBS@
+Cflags: -I${includedir} @PC_CFLAGS@
-- 
1.8.4.5