Specific linking option for rdkafka library

Author: accelerated

Diff for: CMakeLists.txt

@@ -5,6 +5,7 @@ project(cppkafka)
 set(CPPKAFKA_VERSION_MAJOR 0)
 set(CPPKAFKA_VERSION_MINOR 1)
 set(CPPKAFKA_VERSION "${CPPKAFKA_VERSION_MAJOR}.${CPPKAFKA_VERSION_MINOR}")
+set(RDKAFKA_MIN_VERSION 0x00090400)
 
 if(MSVC)
     # Don't always use Wall, since VC's /Wall is ridiculously verbose.
@@ -30,6 +31,7 @@ option(CPPKAFKA_DISABLE_TESTS "Disable build of cppkafka tests." OFF)
 option(CPPKAFKA_DISABLE_EXAMPLES "Disable build of cppkafka examples." OFF)
 option(CPPKAFKA_BOOST_STATIC_LIBS "Link with Boost static libraries." ON)
 option(CPPKAFKA_BOOST_USE_MULTITHREADED "Use Boost multithreaded libraries." ON)
+option(CPPKAFKA_RDKAFKA_STATIC_LIB "Link with Rdkafka static library." OFF)
 
 # Disable output from find_package macro
 if (NOT CPPKAFKA_CMAKE_VERBOSE)

Diff for: README.md

@@ -77,20 +77,25 @@ The following cmake options can be specified:
 * `CPPKAFKA_DISABLE_EXAMPLES` : Disable build of cppkafka examples. Default is `OFF`.
 * `CPPKAFKA_BOOST_STATIC_LIBS` : Link with Boost static libraries. Default is `ON`.
 * `CPPKAFKA_BOOST_USE_MULTITHREADED` : Use Boost multi-threaded libraries. Default is `ON`.
+* `CPPKAFKA_RDKAFKA_STATIC_LIB` : Link to Rdkafka static library. Default is `OFF`.
 
 Example:
 ```Shell
 cmake -DRDKAFKA_ROOT_DIR=/some/other/dir -DCPPKAFKA_BUILD_SHARED=OFF ...
 ```
 
-Note that the `RDKAFKA_ROOT_DIR` must contain the following structure:
+The `RDKAFKA_ROOT_DIR` must contain the following structure. If the system
+architecture is 64-bit and both `lib` and `lib64` folders are available, the `lib64`
+folder location will be selected by cmake.
 
 ```Shell
 ${RDKAFKA_ROOT_DIR}/
                    |
                    + include/librdkafka/rdkafka.h
                    |
                    + lib/librdkafka.a
+                   |
+                   + lib64/librdkafka.a (optional)
 ```
 
 # Using

Diff for: cmake/FindRdKafka.cmake

@@ -1,3 +1,18 @@
+# Override default CMAKE_FIND_LIBRARY_SUFFIXES
+if (CPPKAFKA_RDKAFKA_STATIC_LIB)
+    if (MSVC)
+        set(RDKAFKA_SUFFIX lib)
+    else()
+        set(RDKAFKA_SUFFIX a)
+    endif()
+else()
+    if (MSVC)
+        set(RDKAFKA_SUFFIX dll)
+    else()
+        set(RDKAFKA_SUFFIX so)
+    endif()
+endif()
+
 find_path(RDKAFKA_ROOT_DIR
     NAMES include/librdkafka/rdkafka.h
 )
@@ -7,11 +22,17 @@ find_path(RDKAFKA_INCLUDE_DIR
     HINTS ${RDKAFKA_ROOT_DIR}/include
 )
 
-set(HINT_DIR ${RDKAFKA_ROOT_DIR}/lib)
+# Check lib paths
+if (CPPKAFKA_CMAKE_VERBOSE)
+    get_property(FIND_LIBRARY_32 GLOBAL PROPERTY FIND_LIBRARY_USE_LIB32_PATHS)
+    get_property(FIND_LIBRARY_64 GLOBAL PROPERTY FIND_LIBRARY_USE_LIB64_PATHS)
+    MESSAGE(STATUS "RDKAFKA search 32-bit library paths: ${FIND_LIBRARY_32}")
+    MESSAGE(STATUS "RDKAFKA search 64-bit library paths: ${FIND_LIBRARY_64}")
+endif()
 
 find_library(RDKAFKA_LIBRARY
-    NAMES rdkafka librdkafka
-    HINTS ${HINT_DIR}
+    NAMES rdkafka.${RDKAFKA_SUFFIX} librdkafka.${RDKAFKA_SUFFIX} rdkafka
+    HINTS ${RDKAFKA_ROOT_DIR}/lib
 )
 
 include(FindPackageHandleStandardArgs)
@@ -20,7 +41,7 @@ find_package_handle_standard_args(RDKAFKA DEFAULT_MSG
     RDKAFKA_INCLUDE_DIR
 )
 
-set(CONTENTS "#include <librdkafka/rdkafka.h>\n #if RD_KAFKA_VERSION >= 0x00090400\n int main() { }\n #endif")
+set(CONTENTS "#include <librdkafka/rdkafka.h>\n #if RD_KAFKA_VERSION >= ${RDKAFKA_MIN_VERSION}\n int main() { }\n #endif")
 set(FILE_NAME ${CMAKE_CURRENT_BINARY_DIR}/rdkafka_version_test.c)
 file(WRITE ${FILE_NAME} ${CONTENTS})