RocksDB : Add lookup / compiling with optional compression libraries.

This change add WITH_ROCKSDB_{LZ4,BZIP2,ZSTD,snappy} CMake variables
that can be set to ON/OFF/AUTO.

If variable has default value AUTO, rocksdb links with corresponding
compression library. OFF disables compiling/linking with specific compression
library, ON forces compiling with it (cmake would throw error if library
is not available)

Support for ZLIB is added unconditionally, as it is always there.

cmake/FindLZ4.cmake

+find_path(LZ4_INCLUDE_DIR NAMES lz4.h)
+find_library(LZ4_LIBRARY NAMES lz4)
+
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(
+    LZ4 DEFAULT_MSG
+    LZ4_LIBRARY LZ4_INCLUDE_DIR)
+
+mark_as_advanced(LZ4_INCLUDE_DIR LZ4_LIBRARY)

cmake/FindZSTD.cmake

+find_path(
+    ZSTD_INCLUDE_DIR
+    NAMES "zstd.h"
+)
+
+find_library(
+    ZSTD_LIBRARY
+    NAMES zstd
+)
+
+set(ZSTD_LIBRARIES ${ZSTD_LIBRARY})
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(
+    ZSTD DEFAULT_MSG ZSTD_INCLUDE_DIR ZSTD_LIBRARIES)
+
+mark_as_advanced(ZSTD_INCLUDE_DIR ZSTD_LIBRARIES ZSTD_FOUND)
+

storage/rocksdb/CMakeLists.txt

@@ -152,34 +152,3 @@ IF(MSVC)
   # Some checks in C++ runtime that make debug build much slower
   ADD_DEFINITIONS(-D_ITERATOR_DEBUG_LEVEL=0)
 ENDIF()
-
-# Optional compression libraries.
-#
-# TODO: search compression libraries properly.
-# Use FIND_PACKAGE, CHECK_LIBRARY_EXISTS etc
-IF(MARIAROCKS_NOT_YET)
-IF (NOT "$ENV{WITH_SNAPPY}" STREQUAL "")
-  SET(rocksdb_static_libs ${rocksdb_static_libs}
-  $ENV{WITH_SNAPPY}/libsnappy${PIC_EXT}.a)
-  ADD_DEFINITIONS(-DSNAPPY)
-ENDIF()
-
-IF (NOT "$ENV{WITH_LZ4}" STREQUAL "")
-  SET(rocksdb_static_libs ${rocksdb_static_libs}
-  $ENV{WITH_LZ4}/liblz4${PIC_EXT}.a)
-  ADD_DEFINITIONS(-DLZ4)
-ENDIF()
-
-IF (NOT "$ENV{WITH_BZ2}" STREQUAL "")
-  SET(rocksdb_static_libs ${rocksdb_static_libs}
-  $ENV{WITH_BZ2}/libbz2${PIC_EXT}.a)
-  ADD_DEFINITIONS(-DBZIP2)
-ENDIF()
-
-# link ZSTD only if instructed
-IF (NOT "$ENV{WITH_ZSTD}" STREQUAL "")
-  SET(rocksdb_static_libs ${rocksdb_static_libs}
-  $ENV{WITH_ZSTD}/libzstd${PIC_EXT}.a)
-  ADD_DEFINITIONS(-DZSTD)
-ENDIF()
-ENDIF(MARIAROCKS_NOT_YET)

storage/rocksdb/build_rocksdb.cmake

@@ -11,8 +11,6 @@ INCLUDE_DIRECTORIES(
   ${ROCKSDB_SOURCE_DIR}/third-party/gtest-1.7.0/fused-src
 )
 
-
-
 list(APPEND CMAKE_MODULE_PATH "${ROCKSDB_SOURCE_DIR}/cmake/modules/")
 
 if(WIN32)
@@ -29,18 +27,49 @@ else()
     add_definitions(-DROCKSDB_JEMALLOC)
     set(WITH_JEMALLOC ON)
   endif()
-  option(WITH_ROCKSDB_SNAPPY "build RocksDB with SNAPPY" OFF)
-  if(WITH_ROCKSDB_SNAPPY)
-    find_package(snappy REQUIRED)
-    add_definitions(-DSNAPPY)
-    include_directories(${SNAPPY_INCLUDE_DIR})
-    list(APPEND THIRDPARTY_LIBS ${SNAPPY_LIBRARIES})
+endif()
+
+# Optional compression libraries.
+
+foreach(compression_lib LZ4 BZIP2 ZSTD snappy)
+  FIND_PACKAGE(${compression_lib} QUIET)
+
+  SET(WITH_ROCKSDB_${compression_lib} AUTO CACHE STRING
+  "Build RocksDB  with ${compression_lib} compression. Possible values are 'ON', 'OFF', 'AUTO' and default is 'AUTO'")
+
+  if(${WITH_ROCKSDB_${compression_lib}} STREQUAL "ON"  AND NOT ${${compression_lib}_FOUND})
+    MESSAGE(FATAL_ERROR
+      "${compression_lib} library was not found, but WITH_ROCKSDB${compression_lib} option is ON.\
+      Either set WITH_ROCKSDB${compression_lib} to OFF, or make sure ${compression_lib} is installed")
   endif()
+endforeach()
+
+if(LZ4_FOUND AND (NOT WITH_ROCKSDB_LZ4 STREQUAL "OFF"))
+  add_definitions(-DLZ4)
+  include_directories(${LZ4_INCLUDE_DIR})
+  list(APPEND THIRDPARTY_LIBS ${LZ4_LIBRARY})
 endif()
 
+if(BZIP2_FOUND AND (NOT WITH_ROCKSDB_BZIP2 STREQUAL "OFF"))
+  add_definitions(-DBZIP2)
+  include_directories(${BZIP2_INCLUDE_DIR})
+  list(APPEND THIRDPARTY_LIBS ${BZIP2_LIBRARIES})
+endif()
 
+if(SNAPPY_FOUND  AND (NOT WITH_ROCKSDB_SNAPPY STREQUAL "OFF"))
+  add_definitions(-DSNAPPY)
+  include_directories(${SNAPPY_INCLUDE_DIR})
+  list(APPEND THIRDPARTY_LIBS ${SNAPPY_LIBRARIES})
+endif()
 
+if(ZSTD_FOUND AND (NOT WITH_ROCKSDB_ZSTD STREQUAL "OFF"))
+  add_definitions(-DZSTD)
+  include_directories(${ZSTD_INCLUDE_DIR})
+  list(APPEND THIRDPARTY_LIBS ${ZSTD_LIBRARY})
+endif()
 
+add_definitions(-DZLIB)
+list(APPEND THIRDPARTY_LIBS ${ZLIB_LIBRARY})
 
 if(CMAKE_SYSTEM_NAME MATCHES "Cygwin")
   add_definitions(-fno-builtin-memcmp -DCYGWIN)
@@ -330,7 +359,7 @@ CONFIGURE_FILE(${ROCKSDB_SOURCE_DIR}/util/build_version.cc.in build_version.cc @
 INCLUDE_DIRECTORIES(${ROCKSDB_SOURCE_DIR}/util)
 list(APPEND SOURCES ${CMAKE_CURRENT_BINARY_DIR}/build_version.cc)
 
-ADD_CONVENIENCE_LIBRARY(rocksdblib STATIC ${SOURCES})
+ADD_CONVENIENCE_LIBRARY(rocksdblib ${SOURCES})
 target_link_libraries(rocksdblib ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})
 IF(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
   set_target_properties(rocksdblib PROPERTIES COMPILE_FLAGS "-fPIC -fno-builtin-memcmp -frtti")