From 6aacfb674cc05e5d8deb1c9aa7c2e7ac32e661fd Mon Sep 17 00:00:00 2001
From: Dan Kegel <dank@kegel.com>
Date: Wed, 10 Jun 2020 16:35:44 -0700
Subject: [PATCH] cmake: generate same .pc file contents as configure

---
 CMakeLists.txt  | 23 ++++++++++++++++++-----
 zlib.pc.cmakein | 10 +++++-----
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e75f9a1e..eddf4771 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -817,11 +817,18 @@ if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
     endif()
 endif()
 
-set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib${SUFFIX}.pc)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
-    ${ZLIB_PC} @ONLY)
-configure_file(${CMAKE_CURRENT_BINARY_DIR}/zconf${SUFFIX}.h.cmakein
-    ${CMAKE_CURRENT_BINARY_DIR}/zconf${SUFFIX}.h @ONLY)
+# Refer to prefix symbolically to ease relocation by end user,
+# as Makefile-generated .pc file does.
+if(INSTALL_INC_DIR STREQUAL "${CMAKE_INSTALL_PREFIX}/include")
+  set(PC_INSTALL_INC_DIR "\${prefix}/include")
+else()
+  set(PC_INSTALL_INC_DIR "${INSTALL_INC_DIR}")
+endif()
+if(INSTALL_LIB_DIR STREQUAL "${CMAKE_INSTALL_PREFIX}/lib")
+  set(PC_INSTALL_LIB_DIR "\${exec_prefix}/lib")
+else()
+  set(PC_INSTALL_LIB_DIR "${INSTALL_LIB_DIR}")
+endif()
 
 #============================================================================
 # zlib
@@ -968,6 +975,12 @@ if(NOT DEFINED BUILD_SHARED_LIBS OR BUILD_SHARED_LIBS)
     endif()
 endif()
 
+set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib${SUFFIX}.pc)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
+    ${ZLIB_PC} @ONLY)
+configure_file(${CMAKE_CURRENT_BINARY_DIR}/zconf${SUFFIX}.h.cmakein
+    ${CMAKE_CURRENT_BINARY_DIR}/zconf${SUFFIX}.h @ONLY)
+
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
     install(TARGETS ${ZLIB_INSTALL_LIBRARIES}
         RUNTIME DESTINATION "${INSTALL_BIN_DIR}"
diff --git a/zlib.pc.cmakein b/zlib.pc.cmakein
index 0635b6e3..7744dc2a 100644
--- a/zlib.pc.cmakein
+++ b/zlib.pc.cmakein
@@ -1,12 +1,12 @@
 prefix=@CMAKE_INSTALL_PREFIX@
-exec_prefix=@CMAKE_INSTALL_PREFIX@
-libdir=@INSTALL_LIB_DIR@
-sharedlibdir=@INSTALL_LIB_DIR@
-includedir=@INSTALL_INC_DIR@
+exec_prefix=${prefix}
+libdir=@PC_INSTALL_LIB_DIR@
+sharedlibdir=${libdir}
+includedir=@PC_INSTALL_INC_DIR@
 
 Name: zlib@SUFFIX@
 Description: zlib-ng compression library
-Version: @zlib_VERSION@
+Version: @ZLIB_FULL_VERSION@
 
 Requires:
 Libs: -L${libdir} -L${sharedlibdir} -lz@SUFFIX@
-- 
2.47.2