FindCURL: support COMPONENTS to check features

- Use pkg-config or curl-config to retrieve version,
  supported features and protocols.
- Support optional COMPONENTS to check supported features

Signed-off-by: Hiroshi Miura <miurahr@linux.com>

1 files changed, 73 insertions, 4 deletions

diff --git a/Modules/FindCURL.cmake b/Modules/FindCURL.cmake
index a4b238d..d28dfea 100644
--- a/Modules/FindCURL.cmake
+++ b/Modules/FindCURL.cmake
@@ -7,6 +7,14 @@ FindCURL
 
 Find the native CURL headers and libraries.
 
+This module accept optional COMPONENTS to check supported features and
+protocols::
+
+  PROTOCOLS: ICT FILE FTP FTPS GOPHER HTTP HTTPS IMAP IMAPS LDAP LDAPS POP3
+             POP3S RTMP RTSP SCP SFTP SMB SMBS SMTP SMTPS TELNET TFTP
+  FEATURES:  SSL IPv6 UnixSockets libz AsynchDNS IDN GSS-API PSL SPNEGO
+             Kerberos NTLM NTLM_WB TLS-SRP HTTP2 HTTPS-proxy
+
 IMPORTED Targets
 ^^^^^^^^^^^^^^^^
 
@@ -31,8 +39,20 @@ This module defines the following variables:
   The version of curl found.
 #]=======================================================================]
 
+find_package(PkgConfig QUIET)
+if(PKG_CONFIG_FOUND)
+  pkg_check_modules(PC_CURL QUIET libcurl)
+  if(PC_CURL_FOUND)
+    set(CURL_VERSION_STRING ${PC_CURL_VERSION})
+    pkg_get_variable(CURL_SUPPORTED_PROTOCOLS libcurl supported_protocols)
+    pkg_get_variable(CURL_SUPPORTED_FEATURES libcurl supported_features)
+  endif()
+endif()
+
 # Look for the header file.
-find_path(CURL_INCLUDE_DIR NAMES curl/curl.h)
+find_path(CURL_INCLUDE_DIR
+          NAMES curl/curl.h
+          HINTS ${PC_CURL_INCLUDE_DIRS})
 mark_as_advanced(CURL_INCLUDE_DIR)
 
 if(NOT CURL_LIBRARY)
@@ -45,6 +65,7 @@ if(NOT CURL_LIBRARY)
       curllib_static
     # Windows older "Win32 - MSVC" prebuilts (libcurl.lib, e.g. libcurl-7.15.5-win32-msvc.zip):
       libcurl
+      HINTS ${PC_CURL_LIBRARY_DIRS}
   )
   mark_as_advanced(CURL_LIBRARY_RELEASE)
 
@@ -52,6 +73,7 @@ if(NOT CURL_LIBRARY)
     # Windows MSVC CMake builds in debug configuration on vcpkg:
       libcurl-d_imp
       libcurl-d
+      HINTS ${PC_CURL_LIBRARY_DIRS}
   )
   mark_as_advanced(CURL_LIBRARY_DEBUG)
 
@@ -59,7 +81,7 @@ if(NOT CURL_LIBRARY)
   select_library_configurations(CURL)
 endif()
 
-if(CURL_INCLUDE_DIR)
+if(CURL_INCLUDE_DIR AND NOT CURL_VERSION_STRING)
   foreach(_curl_version_header curlver.h curl.h)
     if(EXISTS "${CURL_INCLUDE_DIR}/curl/${_curl_version_header}")
       file(STRINGS "${CURL_INCLUDE_DIR}/curl/${_curl_version_header}" curl_version_str REGEX "^#define[\t ]+LIBCURL_VERSION[\t ]+\".*\"")
@@ -71,10 +93,57 @@ if(CURL_INCLUDE_DIR)
   endforeach()
 endif()
 
+if(CURL_FIND_COMPONENTS)
+  set(CURL_KNOWN_PROTOCOLS ICT FILE FTP FTPS GOPHER HTTP HTTPS IMAP IMAPS LDAP LDAPS POP3 POP3S RTMP RTSP SCP SFTP SMB SMBS SMTP SMTPS TELNET TFTP)
+  set(CURL_KNOWN_FEATURES  SSL IPv6 UnixSockets libz AsynchDNS IDN GSS-API PSL SPNEGO Kerberos NTLM NTLM_WB TLS-SRP HTTP2 HTTPS-proxy)
+  foreach(component IN LISTS CURL_KNOWN_PROTOCOLS CURL_KNOWN_FEATURES)
+    set(CURL_${component}_FOUND FALSE)
+  endforeach()
+  if(NOT PC_CURL_FOUND)
+    find_program(CURL_CONFIG_EXECUTABLE NAMES curl-config)
+    if(CURL_CONFIG_EXECUTABLE)
+      execute_process(COMMAND ${CURL_CONFIG_EXECUTABLE} --version
+                      OUTPUT_VARIABLE CURL_CONFIG_VERSION_STRING
+                      ERROR_QUIET
+                      OUTPUT_STRIP_TRAILING_WHITESPACE)
+      execute_process(COMMAND ${CURL_CONFIG_EXECUTABLE} --feature
+                      OUTPUT_VARIABLE CURL_CONFIG_FEATURES_STRING
+                      ERROR_QUIET
+                      OUTPUT_STRIP_TRAILING_WHITESPACE)
+      string(REPLACE "\n" ";" CURL_CONFIG_FEATURES "${CURL_CONFIG_FEATURES_STRING}")
+      execute_process(COMMAND ${CURL_CONFIG_EXECUTABLE} --protocols
+                      OUTPUT_VARIABLE CURL_CONFIG_PROTOCOLS_STRING
+                      ERROR_QUIET
+                      OUTPUT_STRIP_TRAILING_WHITESPACE)
+      string(REPLACE "\n" ";" CURL_CONFIG_PROTOCOLS "${CURL_CONFIG_PROTOCOLS_STRING}")
+    endif()
+
+  endif()
+  foreach(component IN LISTS CURL_FIND_COMPONENTS)
+    list(FIND CURL_KNOWN_PROTOCOLS ${component} _found)
+    if(_found)
+      list(FIND CURL_SUPPORTED_PROTOCOLS ${component} _found)
+      if(_found)
+        set(CURL_${component}_FOUND TRUE)
+      elseif(CURL_FIND_REQUIRED)
+        message(FATAL_ERROR "CURL: Required protocol ${component} is not found")
+      endif()
+    else()
+      list(FIND CURL_SUPPORTED_FEATURES ${component} _found)
+      if(_found)
+        set(CURL_${component}_FOUND TRUE)
+      elseif(CURL_FIND_REQUIRED)
+        message(FATAL_ERROR "CURL: Required feature ${component} is not found")
+      endif()
+    endif()
+  endforeach()
+endif()
+
 include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(CURL
+find_package_handle_standard_args(CURL
                                   REQUIRED_VARS CURL_LIBRARY CURL_INCLUDE_DIR
-                                  VERSION_VAR CURL_VERSION_STRING)
+                                  VERSION_VAR CURL_VERSION_STRING
+                                  HANDLE_COMPONENTS)
 
 if(CURL_FOUND)
   set(CURL_LIBRARIES ${CURL_LIBRARY})