summaryrefslogtreecommitdiff
path: root/CMakeLists.txt
blob: f0af6f66c16af1930bbdb17ca612bfb9f517ba9d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
#
# Copyright 2017 The Abseil Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# Most widely used distributions have cmake 3.5 or greater available as of March
# 2019.  A notable exception is RHEL-7 (CentOS7).  You can install a current
# version of CMake by first installing Extra Packages for Enterprise Linux
# (https://fedoraproject.org/wiki/EPEL#Extra_Packages_for_Enterprise_Linux_.28EPEL.29)
# and then issuing `yum install cmake3` on the command line.
cmake_minimum_required(VERSION 3.5)

# Compiler id for Apple Clang is now AppleClang.
if (POLICY CMP0025)
  cmake_policy(SET CMP0025 NEW)
endif (POLICY CMP0025)

# if command can use IN_LIST
if (POLICY CMP0057)
  cmake_policy(SET CMP0057 NEW)
endif (POLICY CMP0057)

# Project version variables are the empty string if version is unspecified
if (POLICY CMP0048)
  cmake_policy(SET CMP0048 NEW)
endif (POLICY CMP0048)

# option() honor variables
if (POLICY CMP0077)
  cmake_policy(SET CMP0077 NEW)
endif (POLICY CMP0077)

project(absl CXX)

# Output directory is correct by default for most build setups. However, when
# building Abseil as a DLL, it is important to have the DLL in the same
# directory as the executable using it. Thus, we put all executables in a single
# /bin directory.
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

# when absl is included as subproject (i.e. using add_subdirectory(abseil-cpp))
# in the source tree of a project that uses it, install rules are disabled.
if(NOT "^${CMAKE_SOURCE_DIR}$" STREQUAL "^${PROJECT_SOURCE_DIR}$")
  option(ABSL_ENABLE_INSTALL "Enable install rule" OFF)
else()
  option(ABSL_ENABLE_INSTALL "Enable install rule" ON)
endif()

list(APPEND CMAKE_MODULE_PATH
  ${CMAKE_CURRENT_LIST_DIR}/CMake
  ${CMAKE_CURRENT_LIST_DIR}/absl/copts
)

include(AbseilInstallDirs)
include(CMakePackageConfigHelpers)
include(AbseilDll)
include(AbseilHelpers)


##
## Using absl targets
##
## all public absl targets are
## exported with the absl:: prefix
##
## e.g absl::base absl::synchronization absl::strings ....
##
## DO NOT rely on the internal targets outside of the prefix


# include current path
list(APPEND ABSL_COMMON_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR})

if("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
  set(ABSL_USING_CLANG ON)
else()
  set(ABSL_USING_CLANG OFF)
endif()

# find dependencies
## pthread
find_package(Threads REQUIRED)

option(ABSL_USE_EXTERNAL_GOOGLETEST
  "If ON, Abseil will assume that the targets for GoogleTest are already provided by the including project. This makes sense when Abseil is used with add_subproject." OFF)


option(ABSL_USE_GOOGLETEST_HEAD
  "If ON, abseil will download HEAD from googletest at config time." OFF)

set(ABSL_LOCAL_GOOGLETEST_DIR "/usr/src/googletest" CACHE PATH
  "If ABSL_USE_GOOGLETEST_HEAD is OFF, specifies the directory of a local googletest checkout."
  )

option(ABSL_RUN_TESTS "If ON, Abseil tests will be run." OFF)

if(${ABSL_RUN_TESTS})
  # enable CTest.  This will set BUILD_TESTING to ON unless otherwise specified
  # on the command line
  include(CTest)

  ## check targets
  if (NOT ABSL_USE_EXTERNAL_GOOGLETEST)
    set(absl_gtest_build_dir ${CMAKE_BINARY_DIR}/googletest-build)
    if(${ABSL_USE_GOOGLETEST_HEAD})
      set(absl_gtest_src_dir ${CMAKE_BINARY_DIR}/googletest-src)
    else()
      set(absl_gtest_src_dir ${ABSL_LOCAL_GOOGLETEST_DIR})
    endif()
    include(CMake/Googletest/DownloadGTest.cmake)
  endif()

  check_target(gtest)
  check_target(gtest_main)
  check_target(gmock)

  list(APPEND ABSL_TEST_COMMON_LIBRARIES
    gtest_main
    gtest
    gmock
    ${CMAKE_THREAD_LIBS_INIT}
  )
endif()

add_subdirectory(absl)

if(ABSL_ENABLE_INSTALL)

  # install as a subdirectory only
  install(EXPORT ${PROJECT_NAME}Targets
    NAMESPACE absl::
    DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
  )

  configure_package_config_file(
    CMake/abslConfig.cmake.in
    "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
    INSTALL_DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
  )
  install(FILES "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
    DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
  )

  # Abseil only has a version in LTS releases.  This mechanism is accomplished
  # Abseil's internal Copybara (https://github.com/google/copybara) workflows and
  # isn't visible in the CMake buildsystem itself.
  if(absl_VERSION)
    write_basic_package_version_file(
      "${PROJECT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake"
      COMPATIBILITY ExactVersion
    )

    install(FILES "${PROJECT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake"
      DESTINATION ${ABSL_INSTALL_CONFIGDIR}
    )
  endif()  # absl_VERSION

  install(DIRECTORY absl
    DESTINATION ${ABSL_INSTALL_INCLUDEDIR}
    FILES_MATCHING
      PATTERN "*.inc"
      PATTERN "*.h"
      PATTERN "copts" EXCLUDE
      PATTERN "testdata" EXCLUDE
    )
endif()  # ABSL_ENABLE_INSTALL