CMake cleanup

- use FIND_PACKAGE(LIBAIO) to find libaio
- Use standard CMake conventions in Find{PMEM,URING}.cmake
- Drop the LIB from LIB{PMEM,URING}_{INCLUDE_DIR,LIBRARIES}
  It is cleaner, and consistent with how other packages are handled in CMake.
  e.g successful FIND_PACKAGE(PMEM) now sets PMEM_FOUND, PMEM_LIBRARIES,
  PMEM_INCLUDE_DIR, not  LIBPMEM_{FOUND,LIBRARIES,INCLUDE_DIR}.
- Decrease the output. use FIND_PACKAGE with QUIET argument.
- for Linux packages, either liburing, or libaio is required
  If liburing is installed, libaio does not need to be present   .
  Use FIND_PACKAGE([LIBAIO|URING] REQUIRED) if either library is required.

1 files changed, 13 insertions, 10 deletions

diff --git a/tpool/CMakeLists.txt b/tpool/CMakeLists.txt
index 213cef7b5de..69440d09490 100644
--- a/tpool/CMakeLists.txt
+++ b/tpool/CMakeLists.txt
@@ -3,24 +3,27 @@ IF(WIN32)
   SET(EXTRA_SOURCES tpool_win.cc aio_win.cc)
 ELSEIF(CMAKE_SYSTEM_NAME STREQUAL "Linux")
   OPTION(WITH_URING "Require that io_uring be used" OFF)
-  FIND_PACKAGE(URING)
+  OPTION(WITH_LIBAIO "Require that libaio is used, unless uring is there" OFF)
+  IF(WITH_URING)
+    SET(URING_REQUIRED REQUIRED)
+  ELSEIF(WITH_LIBAIO)
+    SET(LIBAIO_REQIRED REQUIRED)
+  ENDIF()
+  FIND_PACKAGE(URING QUIET ${URING_REQUIRED})
   IF(URING_FOUND)
     SET(URING_FOUND ${URING_FOUND} PARENT_SCOPE)
     SET(TPOOL_DEFINES "-DHAVE_URING" PARENT_SCOPE)
     ADD_DEFINITIONS(-DHAVE_URING)
-    LINK_LIBRARIES(${LIBURING_LIBRARIES})
-    INCLUDE_DIRECTORIES(${LIBURING_INCLUDE_DIR})
+    LINK_LIBRARIES(${URING_LIBRARIES})
+    INCLUDE_DIRECTORIES(${URING_INCLUDE_DIR})
     SET(EXTRA_SOURCES aio_liburing.cc)
   ELSE()
-    IF(WITH_URING)
-      MESSAGE(FATAL_ERROR "WITH_URING=ON cannot be satisfied")
-    ENDIF()
-    CHECK_INCLUDE_FILES (libaio.h HAVE_LIBAIO_H)
-    CHECK_LIBRARY_EXISTS(aio io_queue_init "" HAVE_LIBAIO)
-    IF(HAVE_LIBAIO_H AND HAVE_LIBAIO)
+    FIND_PACKAGE(LIBAIO QUIET ${LIBAIO_REQUIRED})
+    IF(LIBAIO_FOUND)
       SET(TPOOL_DEFINES "-DLINUX_NATIVE_AIO" PARENT_SCOPE)
       ADD_DEFINITIONS(-DLINUX_NATIVE_AIO)
-      LINK_LIBRARIES(aio)
+      INCLUDE_DIRECTORIES(${LIBAIO_INCLUDE_DIR})
+      LINK_LIBRARIES(${LIBAIO_LIBRARIES})
       SET(EXTRA_SOURCES aio_linux.cc)
     ENDIF()
   ENDIF()