#
# Copyright (c) 2019 Carnegie Mellon University,
# Copyright (c) 2019 Triad National Security, LLC, as operator of
#     Los Alamos National Laboratory.
#
# All rights reserved.
#
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file. See the AUTHORS file for names of contributors.
#

#
# CMakeLists.txt  top-level cmake file for deltafs
# 16-Jun-2016  chuck@ece.cmu.edu
#

#
# deltafs is ... XXX
#

#
# configuration/build:
#   - choose a build directory and "cd" to it
#   - cmake [flags] directory
#   - make
#
#  where directory is the top-level source directory where this file resides.
#
#  general cmake flags:
#    -DCMAKE_INSTALL_PREFIX=/usr/local     -- the prefix for installing
#    -DCMAKE_BUILD_TYPE=type               -- type can be DEBUG, RELEASE, ...
#    -DCMAKE_PREFIX_PATH=/dir              -- external packages
#    -DBUILD_SHARED_LIBS=OFF               -- turn ON for shared libs
#    -DBUILD_TESTS=OFF                     -- turn ON to build tests
#
#     note that CMAKE_PREFIX_PATH can be a list of directories:
#      -DCMAKE_PREFIX_PATH='/dir1;/dir2;/dir3'
#
# general PDLFS config compile time options flags:
#   -DPDLFS_GFLAGS=ON                      -- use gflags for arg parsing
#     - GFLAGS_INCLUDE_DIR: optional hint for finding gflags/gflags.h
#     - GFLAGS_LIBRARY_DIR: optional hint for finding gflags lib
#   -DPDLFS_GLOG=ON                        -- use glog for logging
#   -DPDLFS_SILT_ECT=ON                    -- include SILT ECT code
#   -DPDLFS_MARGO_RPC=ON                   -- compile in margo rpc code
#   -DPDLFS_MERCURY_RPC=ON                 -- compile in mercury rpc code
#   -DPDLFS_RADOS=ON                       -- compile in RADOS env
#     - RADOS_INCLUDE_DIR: optional hint for finding rado/librados.h
#     - RADOS_LIBRARY_DIR: optional hint for finding rados lib
#   -DPDLFS_SNAPPY=ON                      -- compile in snappy compression
#     - SNAPPY_INCLUDE_DIR: optional hint for finding snappy.h
#     - SNAPPY_LIBRARY_DIR: optional hint for finding snappy lib
#   -DPDLFS_VERBOSE=1                      -- set max log verbose level
#
# DELTAFS specific compile time options flags:
#   -DDELTAFS_CXX_STANDARD=11              -- CXX stardard to request
#   -DDELTAFS_CXX_STANDARD_REQUIRED=OFF    -- if CXX stardard must be met
#   -DDELTAFS_BENCHMARKS=ON                -- build our MPI-based benchmarks
#   -DDELTAFS_COMMON_INTREE=OFF            -- in-tree common lib (for devel)
#   -DDELTAFS_MPI=ON                       -- enable MPI in deltafs
#
#    If you want to force a particular MPI compiler other than what we
#    autodetect (e.g. if you want to compile regular stuff with GNU and
#    parallel stuff with Intel), you can set your favorite
#    MPI_<lang>_COMPILER explicitly).
#
#
# note: package config files for external packages must be preinstalled in
#       CMAKE_INSTALL_PATH or on CMAKE_PREFIX_PATH, except as noted.
#

#
# note: cmake 2.8.12 is considered stale, and will be deprecated.
# yet cmake 2.8.12.2 is shipped by ubuntu14.04. ubuntu14.04 won't be end of
# life until Apr 2019, though cmake 3 was later backported to ubuntu14.04
# as cmake3 (use ``sudo apt-get install cmake3'' to install).
cmake_minimum_required (VERSION 2.8.12)

project (DELTAFS)

# add pdlfs-common cmake module directory to the path
set (CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
     "${CMAKE_CURRENT_SOURCE_DIR}/external/pdlfs-common/cmake")

#
# we compile everything with -DDELTAFS by attaching it as a property of
# the common lib.  we also set the common library's name to deltafs-common
# (since we may add deltafs-specific code to it)  we request (but don't
# require) C++ 11 standard for possible performance improvements due it
# its move semantics.
#
set (PDLFS_DFS_COMMON "ON" CACHE BOOL "Include common DFS code")
mark_as_advanced(PDLFS_DFS_COMMON)
set (PDLFS_COMMON_LIBNAME "deltafs-common" CACHE
     STRING "Custom name to install pdlfs-common with")
set (PDLFS_COMMON_DEFINES "DELTAFS" CACHE
     STRING "Additional defines for this version of pdlfs-common")
mark_as_advanced (PDLFS_COMMON_LIBNAME PDLFS_COMMON_DEFINES)
set (DELTAFS_CXX_STANDARD "11" CACHE STRING "C++ std to probe")
set (DELTAFS_CXX_STANDARD_REQUIRED "OFF" CACHE BOOL "C++ std must be met")
mark_as_advanced (DELTAFS_CXX_STANDARD DELTAFS_CXX_STANDARD_REQUIRED)
set_property (CACHE DELTAFS_CXX_STANDARD PROPERTY STRINGS "98" "11")

# note: CMAKE_CXX_STANDARD is not defined until cmake 3.1, and will be
# ignored by cmake 3.0 and before.
#
include (CheckCXXCompilerFlag)
if (CMAKE_VERSION VERSION_LESS "3.1")
    set (cxxstdflag "-std=c++${DELTAFS_CXX_STANDARD}")
    CHECK_CXX_COMPILER_FLAG (${cxxstdflag} flag${cxxstdflag})
    if (${flag${cxxstdflag}})
        add_compile_options (${cxxstdflag})
    else ()
        if (DELTAFS_CXX_STANDARD_REQUIRED)
            message (FATAL_ERROR "Fail to enable CXX ${DELTAFS_CXX_STANDARD}")
        endif ()
    endif ()
else ()
    set (CMAKE_CXX_STANDARD ${DELTAFS_CXX_STANDARD})
    set (CMAKE_CXX_STANDARD_REQUIRED ${DELTAFS_CXX_STANDARD_REQUIRED})
endif ()

# pull in pdlfs handling of generic cmake config
include (cmake-options)

# handle all the common PDLFS options using cmake/pdlfs-options.cmake
include (pdlfs-options)

# user hooks to configure deltafs
set (DELTAFS_BENCHMARKS "OFF" CACHE BOOL "Build benchmarks (requires MPI)")
set (DELTAFS_COMMON_INTREE "OFF" CACHE BOOL
     "Build in-tree common lib (for devel)")
set (DELTAFS_MPI "OFF" CACHE
     BOOL "Enable DELTAFS MPI-based communication")

#
# external packages
#
if (DELTAFS_MPI OR DELTAFS_BENCHMARKS)
    find_package(MPI MODULE)
    # XXX: avoid issues when MPI_CXX_COMPILE_FLAGS contains leading spaces
    string (REPLACE " " ";" MPI_CXX_COMPILE_FLAGS_LIST "${MPI_CXX_COMPILE_FLAGS}")
    if (NOT MPI_FOUND)
        message (FATAL_ERROR "MPI not found (required for DELTAFS_MPI or benchmarks)")
    endif ()
endif ()

#
# we build the in-tree pdlfs-common if DELTAFS_COMMON_INTREE is set,
# otherwise we look for one already built in our install or prefix path.
#
if (DELTAFS_COMMON_INTREE)
    add_subdirectory (external/pdlfs-common/src)
else ()
    message ("OK ${PDLFS_COMPONENT_CFG}") # XXXCDC
    find_package (deltafs-common REQUIRED COMPONENTS ${PDLFS_COMPONENT_CFG})
endif ()

add_subdirectory (src)
if (DELTAFS_BENCHMARKS)
    add_subdirectory (benchmarks)
endif ()