Http client via libcurl

cmake/modules/FindCURL.cmake

@@ -0,0 +1,59 @@
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+#.rst:
+# FindCURL
+# --------
+#
+# Find curl
+#
+# Find the native CURL headers and libraries.
+#
+# ::
+#
+#   CURL_INCLUDE_DIRS   - where to find curl/curl.h, etc.
+#   CURL_LIBRARIES      - List of libraries when using curl.
+#   CURL_FOUND          - True if curl found.
+#   CURL_VERSION_STRING - the version of curl found (since CMake 2.8.8)
+
+# Look for the header file.
+find_path(CURL_INCLUDE_DIR NAMES curl/curl.h)
+mark_as_advanced(CURL_INCLUDE_DIR)
+
+# Look for the library (sorted from most current/relevant entry to least).
+find_library(CURL_LIBRARY NAMES
+    curl
+  # Windows MSVC Makefile:
+    libcurl_a
+  # Windows MSVC prebuilts:
+    curllib
+    libcurl_imp
+    curllib_static
+  # Windows older "Win32 - MSVC" prebuilts (libcurl.lib, e.g. libcurl-7.15.5-win32-msvc.zip):
+    libcurl
+)
+mark_as_advanced(CURL_LIBRARY)
+
+if(CURL_INCLUDE_DIR)
+  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 ]+\".*\"")
+
+      string(REGEX REPLACE "^#define[\t ]+LIBCURL_VERSION[\t ]+\"([^\"]*)\".*" "\\1" CURL_VERSION_STRING "${curl_version_str}")
+      unset(curl_version_str)
+      break()
+    endif()
+  endforeach()
+endif()
+
+find_package_handle_standard_args(CURL
+                                  REQUIRED_VARS CURL_LIBRARY CURL_INCLUDE_DIR
+                                  VERSION_VAR CURL_VERSION_STRING)
+
+if(CURL_FOUND)
+  set(CURL_LIBRARIES ${CURL_LIBRARY})
+  set(CURL_INCLUDE_DIRS ${CURL_INCLUDE_DIR})
+
+  message(STATUS "  Curl libraries:        = ${CURL_LIBRARIES}")
+  message(STATUS "  Curl include dirs:     = ${CURL_INCLUDE_DIRS}")
+endif()