build: install libcurl headers

Ship libcurl headers to system path "${PREFIX}/include/tarantool"
in the case of libcurl included as bundled library or static
build. It is needed to use SMTP client with tarantool's libcurl
instead of system libcurl.

See related issue: https://github.com/tarantool/smtp/issues/24

Closes #4559

CMakeLists.txt

@@ -428,6 +428,13 @@ else()
     find_package(CURL)
 endif()
 
+# Install headers.
+if (ENABLE_BUNDLED_LIBCURL)
+    install(DIRECTORY "${CURL_INCLUDE_DIRS}/curl"
+            DESTINATION ${MODULE_FULL_INCLUDEDIR}
+            FILES_MATCHING PATTERN "*.h")
+endif()
+
 #
 # Export libcurl symbols if the library is linked statically.
 #

changelogs/unreleased/install-headers.md

+## feature/build
+
+* Ship libcurl headers to system path "${PREFIX}/include/tarantool" in the
+  case of libcurl included as bundled library or static build (gh-4559).

rpm/tarantool.spec

@@ -268,6 +268,7 @@ fi
 %{_includedir}/tarantool/luajit.h
 %{_includedir}/tarantool/lualib.h
 %{_includedir}/tarantool/module.h
+%{_includedir}/tarantool/curl
 
 %changelog
 * Tue Sep 12 2017 Roman Tsisyk <roman@tarantool.org> 1.7.5.46-1