Merge pull request #2471 from Exiv2/pc_improve

Improve pkg-config file generation

CMakeLists.txt

@@ -143,8 +143,17 @@ if (EXIV2_TEAM_PACKAGING)
   include(cmake/packaging.cmake)
 endif()
 
-join_paths(libdir_for_pc_file "\${prefix}" "${CMAKE_INSTALL_LIBDIR}")
+# Handle both relative and absolute paths (e.g. NixOS) for a relocatable package
-join_paths(includedir_for_pc_file "\${prefix}" "${CMAKE_INSTALL_INCLUDEDIR}")
+if(IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
+    set(libdir_for_pc_file "${CMAKE_INSTALL_LIBDIR}")
+else()
+    join_paths(libdir_for_pc_file "\${exec_prefix}" "${CMAKE_INSTALL_LIBDIR}")
+endif()
+if(IS_ABSOLUTE "${CMAKE_INSTALL_INCLUDEDIR}")
+    set(includedir_for_pc_file "${CMAKE_INSTALL_INCLUDEDIR}")
+else()
+    join_paths(includedir_for_pc_file "\${prefix}" "${CMAKE_INSTALL_INCLUDEDIR}")
+endif()
 configure_file(cmake/exiv2.pc.in exiv2.pc @ONLY)
 install(FILES ${CMAKE_CURRENT_BINARY_DIR}/exiv2.pc DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
 

cmake/FindIconv.cmake

@@ -1,132 +0,0 @@
-# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
-# file Copyright.txt or https://cmake.org/licensing for details.
-
-# This code is disabled for Visual Studio as explained in README.md
-if ( NOT MSVC )
-
-#[=======================================================================[.rst:
-FindIconv
----------
-
-This module finds the ``iconv()`` POSIX.1 functions on the system.
-These functions might be provided in the regular C library or externally
-in the form of an additional library.
-
-The following variables are provided to indicate iconv support:
-
-.. variable:: Iconv_FOUND
-
-  Variable indicating if the iconv support was found.
-
-.. variable:: Iconv_INCLUDE_DIRS
-
-  The directories containing the iconv headers.
-
-.. variable:: Iconv_LIBRARIES
-
-  The iconv libraries to be linked.
-
-.. variable:: Iconv_IS_BUILT_IN
-
-  A variable indicating whether iconv support is stemming from the
-  C library or not. Even if the C library provides `iconv()`, the presence of
-  an external `libiconv` implementation might lead to this being false.
-
-Additionally, the following :prop_tgt:`IMPORTED` target is being provided:
-
-.. variable:: Iconv::Iconv
-
-  Imported target for using iconv.
-
-The following cache variables may also be set:
-
-.. variable:: Iconv_INCLUDE_DIR
-
-  The directory containing the iconv headers.
-
-.. variable:: Iconv_LIBRARY
-
-  The iconv library (if not implicitly given in the C library).
-
-.. note::
-  On POSIX platforms, iconv might be part of the C library and the cache
-  variables ``Iconv_INCLUDE_DIR`` and ``Iconv_LIBRARY`` might be empty.
-
-#]=======================================================================]
-
-if (WIN32)
-  # If neither C nor CXX are loaded, implicit iconv makes no sense.
-  set(Iconv_IS_BUILT_IN FALSE)
-endif()
-
-# iconv can only be provided in libc on a POSIX system.
-# If any cache variable is already set, we'll skip this test.
-if(NOT DEFINED Iconv_IS_BUILT_IN)
-  if(UNIX AND NOT DEFINED Iconv_INCLUDE_DIR AND NOT DEFINED Iconv_LIBRARY)
-    include(CheckCSourceCompiles)
-    # We always suppress the message here: Otherwise on supported systems
-    # not having iconv in their C library (e.g. those using libiconv)
-    # would always display a confusing "Looking for iconv - not found" message
-    set(CMAKE_FIND_QUIETLY TRUE)
-    # The following code will not work, but it's sufficient to see if it compiles.
-    # Note: libiconv will define the iconv functions as macros, so CheckSymbolExists
-    # will not yield correct results.
-    set(Iconv_IMPLICIT_TEST_CODE
-      "
-      #include <stddef.h>
-      #include <iconv.h>
-      int main() {
-        char *a, *b;
-        size_t i, j;
-        iconv_t ic;
-        ic = iconv_open(\"to\", \"from\");
-        iconv(ic, &a, &i, &b, &j);
-        iconv_close(ic);
-      }
-      "
-    )
-    if(CMAKE_C_COMPILER_LOADED)
-      check_c_source_compiles("${Iconv_IMPLICIT_TEST_CODE}" Iconv_IS_BUILT_IN)
-    else()
-      check_cxx_source_compiles("${Iconv_IMPLICIT_TEST_CODE}" Iconv_IS_BUILT_IN)
-    endif()
-  else()
-    set(Iconv_IS_BUILT_IN FALSE)
-  endif()
-endif()
-
-if(NOT Iconv_IS_BUILT_IN)
-  find_path(Iconv_INCLUDE_DIR
-    NAMES "iconv.h"
-    DOC "iconv include directory")
-  set(Iconv_LIBRARY_NAMES "iconv" "libiconv")
-else()
-  set(Iconv_INCLUDE_DIR "" CACHE FILEPATH "iconv include directory")
-  set(Iconv_LIBRARY_NAMES "c")
-endif()
-
-find_library(Iconv_LIBRARY
-  NAMES ${Iconv_LIBRARY_NAMES}
-  DOC "iconv library (potentially the C library)")
-
-mark_as_advanced(Iconv_INCLUDE_DIR)
-mark_as_advanced(Iconv_LIBRARY)
-
-include(FindPackageHandleStandardArgs)
-if(NOT Iconv_IS_BUILT_IN)
-  find_package_handle_standard_args(Iconv REQUIRED_VARS Iconv_LIBRARY Iconv_INCLUDE_DIR)
-else()
-  find_package_handle_standard_args(Iconv REQUIRED_VARS Iconv_LIBRARY)
-endif()
-
-if(Iconv_FOUND)
-  set(Iconv_INCLUDE_DIRS "${Iconv_INCLUDE_DIR}")
-  set(Iconv_LIBRARIES "${Iconv_LIBRARY}")
-  if(NOT TARGET Iconv::Iconv)
-    add_library(Iconv::Iconv INTERFACE IMPORTED)
-  endif()
-  set_property(TARGET Iconv::Iconv PROPERTY INTERFACE_INCLUDE_DIRECTORIES "${Iconv_INCLUDE_DIRS}")
-  set_property(TARGET Iconv::Iconv PROPERTY INTERFACE_LINK_LIBRARIES "${Iconv_LIBRARIES}")
-endif()
-
-endif()

cmake/exiv2.pc.in

@@ -7,5 +7,7 @@ Name: exiv2
 Description: @PROJECT_DESCRIPTION@
 Version: @PROJECT_VERSION@
 URL: @PACKAGE_URL@
+Requires.private: @requires_private_for_pc_file@
 Libs: -L${libdir} -lexiv2
+Libs.private: @libs_private_for_pc_file@
 Cflags: -I${includedir}

src/CMakeLists.txt

@@ -189,10 +189,12 @@ target_include_directories(exiv2lib SYSTEM PRIVATE
 if (EXIV2_ENABLE_XMP OR EXIV2_ENABLE_EXTERNAL_XMP)
     target_include_directories(exiv2lib PRIVATE ${EXPAT_INCLUDE_DIR})
     target_link_libraries(exiv2lib PRIVATE EXPAT::EXPAT)
+    list(APPEND requires_private_list "expat")
 endif()
 
 if (EXIV2_ENABLE_XMP)
     target_link_libraries(exiv2lib PRIVATE exiv2-xmp)
+    list(APPEND libs_private_list "exiv2-xmp")
 elseif(EXIV2_ENABLE_EXTERNAL_XMP)
     target_link_libraries(exiv2lib PUBLIC ${XMPSDK_LIBRARY})
     target_include_directories(exiv2lib PUBLIC ${XMPSDK_INCLUDE_DIR})
@@ -211,12 +213,11 @@ target_include_directories(exiv2lib_int PUBLIC
 )
 
 if (EXIV2_ENABLE_WEBREADY)
-
     if( EXIV2_ENABLE_CURL )
         target_include_directories(exiv2lib SYSTEM PRIVATE ${CURL_INCLUDE_DIR} )
         target_link_libraries(exiv2lib PRIVATE ${CURL_LIBRARIES})
+        list(APPEND requires_private_list "libcurl")
     endif()
-
 endif()
 
 if (WIN32)
@@ -239,25 +240,31 @@ else()
 endif()
 
 if( EXIV2_ENABLE_PNG )
-	target_link_libraries( exiv2lib PRIVATE ZLIB::ZLIB)
+    target_link_libraries( exiv2lib PRIVATE ZLIB::ZLIB)
+    list(APPEND requires_private_list "zlib")
 endif()
 
 if( EXIV2_ENABLE_BMFF AND BROTLI_FOUND )
     target_link_libraries( exiv2lib PRIVATE ${Brotli_LIBRARIES})
     target_include_directories(exiv2lib PRIVATE ${Brotli_INCLUDE_DIRS})
+    list(APPEND requires_private_list "libbrotlidec")
 endif()
 
 if( EXIV2_ENABLE_NLS )
     target_link_libraries(exiv2lib PRIVATE ${Intl_LIBRARIES})
     target_include_directories(exiv2lib PRIVATE ${Intl_INCLUDE_DIRS})
     target_include_directories(exiv2lib_int PRIVATE ${Intl_INCLUDE_DIRS})
+    if( Intl_LIBRARIES )
+        list(APPEND libs_private_list "intl")
+    endif()
     # Definition needed for translations
     join_paths(EXV_LOCALEDIR ".." "${CMAKE_INSTALL_LOCALEDIR}")
     target_compile_definitions(exiv2lib PUBLIC EXV_LOCALEDIR="${EXV_LOCALEDIR}")
 endif()
 
-if( ICONV_FOUND )
+if( Iconv_FOUND AND Iconv_LIBRARIES )
     target_link_libraries( exiv2lib PRIVATE Iconv::Iconv )
+    list(APPEND libs_private_list "iconv")
 endif()
 
 if( EXIV2_ENABLE_INIH )
@@ -265,8 +272,21 @@ if( EXIV2_ENABLE_INIH )
   target_link_libraries( exiv2lib_int PRIVATE inih::inireader )
   target_link_libraries( exiv2lib PRIVATE inih::libinih )
   target_link_libraries( exiv2lib PRIVATE inih::inireader )
+  list(APPEND requires_private_list "INIReader")
 endif()
 
+# Convert private lists to delimited strings
+list(SORT libs_private_list)
+string(REPLACE ";" " -l" libs_private_string "${libs_private_list}")
+if(libs_private_string)
+    string(PREPEND libs_private_string "-l")
+endif()
+list(SORT requires_private_list)
+string(REPLACE ";" ", " requires_private_string "${requires_private_list}")
+
+set(libs_private_for_pc_file "${libs_private_string}" PARENT_SCOPE)
+set(requires_private_for_pc_file "${requires_private_string}" PARENT_SCOPE)
+
 write_basic_package_version_file(exiv2ConfigVersion.cmake COMPATIBILITY ExactVersion)
 
 install(TARGETS exiv2lib EXPORT exiv2Config