[libtorrent] add iconv feature on windows and clean up portfile (#11257)

ports/libtorrent/CONTROL

@@ -1,5 +1,5 @@
 Source: libtorrent
-Version: 1.2.6
+Version: 1.2.6-1
 Homepage: https://github.com/arvidn/libtorrent
 Description: An efficient feature complete C++ BitTorrent implementation
 Build-Depends: openssl, boost-system, boost-date-time, boost-chrono, boost-random, boost-asio, boost-crc, boost-config, boost-iterator, boost-scope-exit, boost-multiprecision
@@ -11,6 +11,10 @@ Description: build with deprecated functions enabled
 Feature: examples
 Description: build the examples in the examples directory
 
+Feature: iconv
+Build-Depends: libiconv (windows)
+Description: build with libiconv on Windows
+
 Feature: python
 Build-Depends: boost-python, libtorrent[deprfun]
 Description: build the python bindings in bindings/python directory

ports/libtorrent/fix_find_iconv.patch

@@ -0,0 +1,35 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 303f905e4..6bdbc5ac4 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -603,24 +603,19 @@ target_optional_compile_definitions(torrent-rasterbar PUBLIC FEATURE NAME mutabl
+ target_optional_compile_definitions(torrent-rasterbar PUBLIC FEATURE NAME streaming DEFAULT ON
+ 	DESCRIPTION "Enables support for piece deadline" DISABLED TORRENT_DISABLE_STREAMING)
+ 
+-find_public_dependency(Iconv)
+-if(MSVC)
+-	set(iconv_package_type OPTIONAL)
+-else()
+-	set(iconv_package_type RECOMMENDED)
+-endif()
++find_public_dependency(unofficial-iconv REQUIRED)
+ 
+-set_package_properties(Iconv
++set_package_properties(unofficial-iconv
+ 	PROPERTIES
+ 		URL "https://www.gnu.org/software/libiconv/"
+-		DESCRIPTION "GNU encoding conversion library"
+-		TYPE ${iconv_package_type}
++		DESCRIPTION "GNU encoding conversion library (unofficial vcpkg CMake port)"
++		TYPE REQUIRED
+ 		PURPOSE "Convert strings between various encodings"
+ )
+ 
+-if(Iconv_FOUND)
++if(unofficial-iconv_FOUND)
+ 	target_compile_definitions(torrent-rasterbar PUBLIC TORRENT_USE_ICONV)
+-	target_link_libraries(torrent-rasterbar PRIVATE Iconv::Iconv)
++	target_link_libraries(torrent-rasterbar PRIVATE unofficial::iconv::libiconv unofficial::iconv::libcharset)
+ endif()
+ 
+ find_public_dependency(OpenSSL)

ports/libtorrent/no_use_iconv.patch

@@ -0,0 +1,31 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 303f905e4..1810c23c6 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -603,26 +603,6 @@ target_optional_compile_definitions(torrent-rasterbar PUBLIC FEATURE NAME mutabl
+ target_optional_compile_definitions(torrent-rasterbar PUBLIC FEATURE NAME streaming DEFAULT ON
+ 	DESCRIPTION "Enables support for piece deadline" DISABLED TORRENT_DISABLE_STREAMING)
+ 
+-find_public_dependency(Iconv)
+-if(MSVC)
+-	set(iconv_package_type OPTIONAL)
+-else()
+-	set(iconv_package_type RECOMMENDED)
+-endif()
+-
+-set_package_properties(Iconv
+-	PROPERTIES
+-		URL "https://www.gnu.org/software/libiconv/"
+-		DESCRIPTION "GNU encoding conversion library"
+-		TYPE ${iconv_package_type}
+-		PURPOSE "Convert strings between various encodings"
+-)
+-
+-if(Iconv_FOUND)
+-	target_compile_definitions(torrent-rasterbar PUBLIC TORRENT_USE_ICONV)
+-	target_link_libraries(torrent-rasterbar PRIVATE Iconv::Iconv)
+-endif()
+-
+ find_public_dependency(OpenSSL)
+ set_package_properties(OpenSSL
+ 	PROPERTIES

ports/libtorrent/portfile.cmake

@@ -6,12 +6,19 @@ if(VCPKG_TARGET_IS_WINDOWS)
         message(FATAL_ERROR "The python feature is currently broken on Windows")
     endif()
 
-    # Ensure OPENSSL_USE_STATIC_LIBS is set to ON
+    if("iconv" IN_LIST FEATURES)
+        set(ICONV_PATCH "fix_find_iconv.patch")
+    else()
+        # prevent picking up libiconv if it happens to already be installed
+        set(ICONV_PATCH "no_use_iconv.patch")
+    endif()
+
+    # Ensure "OPENSSL_USE_STATIC_LIBS" is set to ON
     # when statically linking against OpenSSL on Windows.
     # Also ensure "static_runtime" will be used when statically linking against the runtime.
     # Prevents OpenSSL crypt32.lib linking errors.
     if(VCPKG_CRT_LINKAGE STREQUAL "static")
-        set(LIBTORRENT_STATIC_RUNTIME ON)
+        set(_static_runtime ON)
     elseif(VCPKG_LIBRARY_LINKAGE STREQUAL "static")
         set(_OPENSSL_USE_STATIC_LIBS ON)
     endif()
@@ -32,7 +39,7 @@ if("python" IN_LIST FEATURES)
     vcpkg_add_to_path(${PYTHON3_PATH})
 
     file(GLOB BOOST_PYTHON_LIB "${CURRENT_INSTALLED_DIR}/lib/*boost_python*")
-    string(REGEX REPLACE ".*(python)([0-9])([0-9]+).*" "\\1\\2\\3" BOOST_PYTHON_MODULE "${BOOST_PYTHON_LIB}")
+    string(REGEX REPLACE ".*(python)([0-9])([0-9]+).*" "\\1\\2\\3" _boost-python-module-name "${BOOST_PYTHON_LIB}")
 endif()
 
 vcpkg_from_github(
@@ -44,6 +51,7 @@ vcpkg_from_github(
     PATCHES
         add-datetime-to-boost-libs.patch
         fix_python_cmake.patch
+        ${ICONV_PATCH}
 )
 
 vcpkg_configure_cmake(
@@ -51,24 +59,15 @@ vcpkg_configure_cmake(
     PREFER_NINJA # Disable this option if project cannot be built with Ninja
     OPTIONS
         ${FEATURE_OPTIONS}
-        -Dboost-python-module-name=${BOOST_PYTHON_MODULE}
-        -Dstatic_runtime=${LIBTORRENT_STATIC_RUNTIME}
+        -Dboost-python-module-name=${_boost-python-module-name}
+        -Dstatic_runtime=${_static_runtime}
         -DOPENSSL_USE_STATIC_LIBS=${_OPENSSL_USE_STATIC_LIBS}
         -DPython3_USE_STATIC_LIBS=ON
 )
 
 vcpkg_install_cmake()
 
-file(READ ${CURRENT_PACKAGES_DIR}/include/libtorrent/aux_/export.hpp EXPORT_H)
-string(REPLACE "defined TORRENT_BUILDING_SHARED" "0" EXPORT_H "${EXPORT_H}")
-if (VCPKG_LIBRARY_LINKAGE STREQUAL "dynamic")
-    string(REPLACE "defined TORRENT_LINKING_SHARED" "1" EXPORT_H "${EXPORT_H}")
-else()
-    string(REPLACE "defined TORRENT_LINKING_SHARED" "0" EXPORT_H "${EXPORT_H}")
-endif()
-file(WRITE ${CURRENT_PACKAGES_DIR}/include/libtorrent/aux_/export.hpp "${EXPORT_H}")
-
-vcpkg_fixup_cmake_targets(CONFIG_PATH lib/cmake/LibtorrentRasterbar TARGET_PATH share/libtorrentrasterbar)
+vcpkg_fixup_cmake_targets(CONFIG_PATH lib/cmake/LibtorrentRasterbar TARGET_PATH share/LibtorrentRasterbar)
 
 # Handle copyright
 file(INSTALL ${SOURCE_PATH}/LICENSE DESTINATION ${CURRENT_PACKAGES_DIR}/share/${PORT} RENAME copyright)