Cannot build against system libcurl

[amadio]

The reason is that the library is called libcurl.so and needs to be linked as -lcurl not -llibcurl. However, the build system has no code to support the case in which the embedded library is not used. See the error below.

FAILED: src/libdavix.so.0.8.0 
: && /usr/bin/x86_64-pc-linux-gnu-g++ -fPIC -march=native -O2 -pipe -std=c++11  -Wl,-O1 -Wl,--as-needed -shared -Wl,-soname,libdavix.so.0 -o src/libdavix.so.0.8.0 deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_207.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_acl3744.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_alloc.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_auth.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_basic.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_compress.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_dates.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_i18n.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_locks.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_md5.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_ntlm.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_oldacl.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_pkcs11.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_props.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_redirect.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_request.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_session.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_socket.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_socks.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_sspi.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_string.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_uri.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_utils.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_xml.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_xmlreq.c.o deps/libneon/CMakeFiles/LibNeonObjects.dir/src/ne_openssl.c.o src/CMakeFiles/libdavix.dir/auth/davix_openssl.cpp.o src/CMakeFiles/libdavix.dir/auth/davixauth.cpp.o src/CMakeFiles/libdavix.dir/auth/davixx509cred.cpp.o src/CMakeFiles/libdavix.dir/backend/BackendRequest.cpp.o src/CMakeFiles/libdavix.dir/backend/SessionFactory.cpp.o src/CMakeFiles/libdavix.dir/backend/StandaloneNeonRequest.cpp.o src/CMakeFiles/libdavix.dir/core/ContentProvider.cpp.o src/CMakeFiles/libdavix.dir/core/RedirectionResolver.cpp.o src/CMakeFiles/libdavix.dir/curl/CurlSession.cpp.o src/CMakeFiles/libdavix.dir/curl/CurlSessionFactory.cpp.o src/CMakeFiles/libdavix.dir/curl/HeaderlineParser.cpp.o src/CMakeFiles/libdavix.dir/curl/ResponseBuffer.cpp.o src/CMakeFiles/libdavix.dir/curl/StandaloneCurlRequest.cpp.o src/CMakeFiles/libdavix.dir/deprecated/httpcachetoken.cpp.o src/CMakeFiles/libdavix.dir/file/davfile.cpp.o src/CMakeFiles/libdavix.dir/file/davposix.cpp.o src/CMakeFiles/libdavix.dir/fileops/AzureIO.cpp.o src/CMakeFiles/libdavix.dir/fileops/chain_factory.cpp.o src/CMakeFiles/libdavix.dir/fileops/davix_reliability_ops.cpp.o src/CMakeFiles/libdavix.dir/fileops/davmeta.cpp.o src/CMakeFiles/libdavix.dir/fileops/fileutils.cpp.o src/CMakeFiles/libdavix.dir/fileops/httpiochain.cpp.o src/CMakeFiles/libdavix.dir/fileops/httpiovec.cpp.o src/CMakeFiles/libdavix.dir/fileops/iobuffmap.cpp.o src/CMakeFiles/libdavix.dir/fileops/S3IO.cpp.o src/CMakeFiles/libdavix.dir/fileops/SwiftIO.cpp.o src/CMakeFiles/libdavix.dir/hooks/davix_hooks.cpp.o src/CMakeFiles/libdavix.dir/libs/alibxx/chrono/timepoint.cpp.o src/CMakeFiles/libdavix.dir/libs/alibxx/crypto/base64.cpp.o src/CMakeFiles/libdavix.dir/libs/alibxx/crypto/hmacsha.cpp.o src/CMakeFiles/libdavix.dir/libs/alibxx/str/format.cpp.o src/CMakeFiles/libdavix.dir/libs/datetime/datetime_utils.cpp.o src/CMakeFiles/libdavix.dir/modules/modules_profiles.cpp.o src/CMakeFiles/libdavix.dir/neon/neonrequest.cpp.o src/CMakeFiles/libdavix.dir/neon/neonsession.cpp.o src/CMakeFiles/libdavix.dir/neon/neonsessionfactory.cpp.o src/CMakeFiles/libdavix.dir/params/davixrequestparams.cpp.o src/CMakeFiles/libdavix.dir/request/httprequest.cpp.o src/CMakeFiles/libdavix.dir/status/DavixStatus.cpp.o src/CMakeFiles/libdavix.dir/status/davixstatusrequest.cpp.o src/CMakeFiles/libdavix.dir/utils/checksum_extractor.cpp.o src/CMakeFiles/libdavix.dir/utils/CompatibilityHacks.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_azure_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_gcloud_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_logger.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_misc_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_cs3_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_s3_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/davix_swift_utils.cpp.o src/CMakeFiles/libdavix.dir/utils/simple_get_pass.cpp.o src/CMakeFiles/libdavix.dir/utils/stringutils.cpp.o src/CMakeFiles/libdavix.dir/utils/davixuri.cpp.o src/CMakeFiles/libdavix.dir/xml/azurepropparser.cpp.o src/CMakeFiles/libdavix.dir/xml/davdeletexmlparser.cpp.o src/CMakeFiles/libdavix.dir/xml/davix_ptree.cpp.o src/CMakeFiles/libdavix.dir/xml/davpropxmlparser.cpp.o src/CMakeFiles/libdavix.dir/xml/davxmlparser.cpp.o src/CMakeFiles/libdavix.dir/xml/metalinkparser.cpp.o src/CMakeFiles/libdavix.dir/xml/s3deleteparser.cpp.o src/CMakeFiles/libdavix.dir/xml/S3MultiPartInitiationParser.cpp.o src/CMakeFiles/libdavix.dir/xml/s3propparser.cpp.o src/CMakeFiles/libdavix.dir/xml/swiftpropparser.cpp.o src/CMakeFiles/libdavix.dir/davixcontext.cpp.o  -llibcurl  -lssl  -lcrypto  -lxml2  -lpthread  -luuid  -lz && :
/usr/lib/gcc/x86_64-pc-linux-gnu/10.3.0/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -llibcurl
collect2: error: ld returned 1 exit status

For now, in order to package Davix, I am using the following patch:

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c65ed46b..35950a9a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -117,6 +117,8 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CXX11_FLAG_ENABLE}")
 if(EMBEDDED_LIBCURL)
   include(buildCurl REQUIRED)
   buildCurl()
+else()
+  find_package(CURL REQUIRED)
 endif()
 
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}/deps/libneon/src/ ${UUID_INCLUDE_DIRS})
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 79a8858b..53455abb 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -108,7 +108,7 @@ add_library(libdavix  SHARED ${DAVIX_SOURCES} )
 
 target_include_directories(libdavix PRIVATE ${DAVIX_INTERNAL_INCLUDES} )
 target_link_libraries(libdavix
-  PRIVATE libcurl
+  PRIVATE CURL::libcurl
   PUBLIC ${LIBSSL_PKG_LIBRARIES}
          ${LIBXML2_LIBRARIES}
          ${CMAKE_THREAD_LIBS_INIT}
@@ -146,7 +146,7 @@ set_target_properties(libdavix_static PROPERTIES
 target_include_directories(libdavix_static PRIVATE ${DAVIX_INTERNAL_INCLUDES} )
 
 target_link_libraries(libdavix_static
-  PRIVATE libcurl
+  PRIVATE CURL::libcurl
   PUBLIC  ${OPENSSL_LIBRARIES}
           ${CMAKE_THREAD_LIBS_INIT}
           dl ${UUID_LIBRARIES}

However, that is not a full solution, as that breaks the case with embedded libcurl. It would be nice to have davix support building against all external libraries rather than only the embedded ones. Thanks!

[amadio]

Fixed by 78c00e1.