xref: /aosp_15_r20/external/openscreen/third_party/abseil/src/CMake/AbseilHelpers.cmake (revision 3f982cf4871df8771c9d4abe6e9a6f8d829b2736)
1#
2# Copyright 2017 The Abseil Authors.
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#    https://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15#
16
17include(CMakeParseArguments)
18include(AbseilConfigureCopts)
19include(AbseilDll)
20include(AbseilInstallDirs)
21
22# The IDE folder for Abseil that will be used if Abseil is included in a CMake
23# project that sets
24#    set_property(GLOBAL PROPERTY USE_FOLDERS ON)
25# For example, Visual Studio supports folders.
26if(NOT DEFINED ABSL_IDE_FOLDER)
27  set(ABSL_IDE_FOLDER Abseil)
28endif()
29
30# absl_cc_library()
31#
32# CMake function to imitate Bazel's cc_library rule.
33#
34# Parameters:
35# NAME: name of target (see Note)
36# HDRS: List of public header files for the library
37# SRCS: List of source files for the library
38# DEPS: List of other libraries to be linked in to the binary targets
39# COPTS: List of private compile options
40# DEFINES: List of public defines
41# LINKOPTS: List of link options
42# PUBLIC: Add this so that this library will be exported under absl::
43# Also in IDE, target will appear in Abseil folder while non PUBLIC will be in Abseil/internal.
44# TESTONLY: When added, this target will only be built if user passes -DABSL_RUN_TESTS=ON to CMake.
45#
46# Note:
47# By default, absl_cc_library will always create a library named absl_${NAME},
48# and alias target absl::${NAME}.  The absl:: form should always be used.
49# This is to reduce namespace pollution.
50#
51# absl_cc_library(
52#   NAME
53#     awesome
54#   HDRS
55#     "a.h"
56#   SRCS
57#     "a.cc"
58# )
59# absl_cc_library(
60#   NAME
61#     fantastic_lib
62#   SRCS
63#     "b.cc"
64#   DEPS
65#     absl::awesome # not "awesome" !
66#   PUBLIC
67# )
68#
69# absl_cc_library(
70#   NAME
71#     main_lib
72#   ...
73#   DEPS
74#     absl::fantastic_lib
75# )
76#
77# TODO: Implement "ALWAYSLINK"
78function(absl_cc_library)
79  cmake_parse_arguments(ABSL_CC_LIB
80    "DISABLE_INSTALL;PUBLIC;TESTONLY"
81    "NAME"
82    "HDRS;SRCS;COPTS;DEFINES;LINKOPTS;DEPS"
83    ${ARGN}
84  )
85
86  if(ABSL_CC_LIB_TESTONLY AND NOT ABSL_RUN_TESTS)
87    return()
88  endif()
89
90  if(ABSL_ENABLE_INSTALL)
91    set(_NAME "${ABSL_CC_LIB_NAME}")
92  else()
93    set(_NAME "absl_${ABSL_CC_LIB_NAME}")
94  endif()
95
96  # Check if this is a header-only library
97  # Note that as of February 2019, many popular OS's (for example, Ubuntu
98  # 16.04 LTS) only come with cmake 3.5 by default.  For this reason, we can't
99  # use list(FILTER...)
100  set(ABSL_CC_SRCS "${ABSL_CC_LIB_SRCS}")
101  foreach(src_file IN LISTS ABSL_CC_SRCS)
102    if(${src_file} MATCHES ".*\\.(h|inc)")
103      list(REMOVE_ITEM ABSL_CC_SRCS "${src_file}")
104    endif()
105  endforeach()
106
107  if("${ABSL_CC_SRCS}" STREQUAL "")
108    set(ABSL_CC_LIB_IS_INTERFACE 1)
109  else()
110    set(ABSL_CC_LIB_IS_INTERFACE 0)
111  endif()
112
113  # Determine this build target's relationship to the DLL. It's one of four things:
114  # 1. "dll"     -- This target is part of the DLL
115  # 2. "dll_dep" -- This target is not part of the DLL, but depends on the DLL.
116  #                 Note that we assume any target not in the DLL depends on the
117  #                 DLL. This is not a technical necessity but a convenience
118  #                 which happens to be true, because nearly every target is
119  #                 part of the DLL.
120  # 3. "shared"  -- This is a shared library, perhaps on a non-windows platform
121  #                 where DLL doesn't make sense.
122  # 4. "static"  -- This target does not depend on the DLL and should be built
123  #                 statically.
124  if (${ABSL_BUILD_DLL})
125    if(ABSL_ENABLE_INSTALL)
126      absl_internal_dll_contains(TARGET ${_NAME} OUTPUT _in_dll)
127    else()
128      absl_internal_dll_contains(TARGET ${ABSL_CC_LIB_NAME} OUTPUT _in_dll)
129    endif()
130    if (${_in_dll})
131      # This target should be replaced by the DLL
132      set(_build_type "dll")
133      set(ABSL_CC_LIB_IS_INTERFACE 1)
134    else()
135      # Building a DLL, but this target is not part of the DLL
136      set(_build_type "dll_dep")
137    endif()
138  elseif(BUILD_SHARED_LIBS)
139    set(_build_type "shared")
140  else()
141    set(_build_type "static")
142  endif()
143
144  # Generate a pkg-config file for every library:
145  if(${_build_type} STREQUAL "static" OR ${_build_type} STREQUAL "shared")
146    if(NOT ABSL_CC_LIB_TESTONLY)
147      if(absl_VERSION)
148        set(PC_VERSION "${absl_VERSION}")
149      else()
150        set(PC_VERSION "head")
151      endif()
152      foreach(dep ${ABSL_CC_LIB_DEPS})
153        if(${dep} MATCHES "^absl::(.*)")
154          set(PC_DEPS "${PC_DEPS} absl_${CMAKE_MATCH_1} = ${PC_VERSION}")
155        endif()
156      endforeach()
157      foreach(cflag ${ABSL_CC_LIB_COPTS})
158        if(${cflag} MATCHES "^(-Wno|/wd)")
159          # These flags are needed to suppress warnings that might fire in our headers.
160          set(PC_CFLAGS "${PC_CFLAGS} ${cflag}")
161        elseif(${cflag} MATCHES "^(-W|/w[1234eo])")
162          # Don't impose our warnings on others.
163        else()
164          set(PC_CFLAGS "${PC_CFLAGS} ${cflag}")
165        endif()
166      endforeach()
167      FILE(GENERATE OUTPUT "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc" CONTENT "\
168prefix=${CMAKE_INSTALL_PREFIX}\n\
169exec_prefix=\${prefix}\n\
170libdir=\${prefix}/lib\n\
171includedir=\${prefix}/include\n\
172\n\
173Name: absl_${_NAME}\n\
174Description: Abseil ${_NAME} library\n\
175URL: https://abseil.io/\n\
176Version: ${PC_VERSION}\n\
177Requires.private:${PC_DEPS}\n\
178Libs: -L\${libdir} $<JOIN:${ABSL_CC_LIB_LINKOPTS}, > $<$<NOT:$<BOOL:${ABSL_CC_LIB_IS_INTERFACE}>>:-labsl_${_NAME}>\n\
179Cflags: -I\${includedir}${PC_CFLAGS}\n")
180      INSTALL(FILES "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc"
181              DESTINATION "${CMAKE_INSTALL_PREFIX}/lib/pkgconfig")
182    endif()
183  endif()
184
185  if(NOT ABSL_CC_LIB_IS_INTERFACE)
186    if(${_build_type} STREQUAL "dll_dep")
187      # This target depends on the DLL. When adding dependencies to this target,
188      # any depended-on-target which is contained inside the DLL is replaced
189      # with a dependency on the DLL.
190      add_library(${_NAME} STATIC "")
191      target_sources(${_NAME} PRIVATE ${ABSL_CC_LIB_SRCS} ${ABSL_CC_LIB_HDRS})
192      absl_internal_dll_targets(
193        DEPS ${ABSL_CC_LIB_DEPS}
194        OUTPUT _dll_deps
195      )
196      target_link_libraries(${_NAME}
197        PUBLIC ${_dll_deps}
198        PRIVATE
199          ${ABSL_CC_LIB_LINKOPTS}
200          ${ABSL_DEFAULT_LINKOPTS}
201      )
202
203      if (ABSL_CC_LIB_TESTONLY)
204        set(_gtest_link_define "GTEST_LINKED_AS_SHARED_LIBRARY=1")
205      else()
206        set(_gtest_link_define)
207      endif()
208
209      target_compile_definitions(${_NAME}
210        PUBLIC
211          ABSL_CONSUME_DLL
212          "${_gtest_link_define}"
213      )
214
215    elseif(${_build_type} STREQUAL "static" OR ${_build_type} STREQUAL "shared")
216      add_library(${_NAME} "")
217      target_sources(${_NAME} PRIVATE ${ABSL_CC_LIB_SRCS} ${ABSL_CC_LIB_HDRS})
218      target_link_libraries(${_NAME}
219      PUBLIC ${ABSL_CC_LIB_DEPS}
220      PRIVATE
221        ${ABSL_CC_LIB_LINKOPTS}
222        ${ABSL_DEFAULT_LINKOPTS}
223      )
224    else()
225      message(FATAL_ERROR "Invalid build type: ${_build_type}")
226    endif()
227
228    # Linker language can be inferred from sources, but in the case of DLLs we
229    # don't have any .cc files so it would be ambiguous. We could set it
230    # explicitly only in the case of DLLs but, because "CXX" is always the
231    # correct linker language for static or for shared libraries, we set it
232    # unconditionally.
233    set_property(TARGET ${_NAME} PROPERTY LINKER_LANGUAGE "CXX")
234
235    target_include_directories(${_NAME}
236      PUBLIC
237        "$<BUILD_INTERFACE:${ABSL_COMMON_INCLUDE_DIRS}>"
238        $<INSTALL_INTERFACE:${ABSL_INSTALL_INCLUDEDIR}>
239    )
240    target_compile_options(${_NAME}
241      PRIVATE ${ABSL_CC_LIB_COPTS})
242    target_compile_definitions(${_NAME} PUBLIC ${ABSL_CC_LIB_DEFINES})
243
244    # Add all Abseil targets to a a folder in the IDE for organization.
245    if(ABSL_CC_LIB_PUBLIC)
246      set_property(TARGET ${_NAME} PROPERTY FOLDER ${ABSL_IDE_FOLDER})
247    elseif(ABSL_CC_LIB_TESTONLY)
248      set_property(TARGET ${_NAME} PROPERTY FOLDER ${ABSL_IDE_FOLDER}/test)
249    else()
250      set_property(TARGET ${_NAME} PROPERTY FOLDER ${ABSL_IDE_FOLDER}/internal)
251    endif()
252
253    # INTERFACE libraries can't have the CXX_STANDARD property set
254    set_property(TARGET ${_NAME} PROPERTY CXX_STANDARD ${ABSL_CXX_STANDARD})
255    set_property(TARGET ${_NAME} PROPERTY CXX_STANDARD_REQUIRED ON)
256
257    # When being installed, we lose the absl_ prefix.  We want to put it back
258    # to have properly named lib files.  This is a no-op when we are not being
259    # installed.
260    if(ABSL_ENABLE_INSTALL)
261      set_target_properties(${_NAME} PROPERTIES
262        OUTPUT_NAME "absl_${_NAME}"
263        # TODO(b/173696973): Figure out how to set SOVERSION for LTS releases.
264        SOVERSION 0
265      )
266    endif()
267  else()
268    # Generating header-only library
269    add_library(${_NAME} INTERFACE)
270    target_include_directories(${_NAME}
271      INTERFACE
272        "$<BUILD_INTERFACE:${ABSL_COMMON_INCLUDE_DIRS}>"
273        $<INSTALL_INTERFACE:${ABSL_INSTALL_INCLUDEDIR}>
274      )
275
276    if (${_build_type} STREQUAL "dll")
277        set(ABSL_CC_LIB_DEPS abseil_dll)
278    endif()
279
280    target_link_libraries(${_NAME}
281      INTERFACE
282        ${ABSL_CC_LIB_DEPS}
283        ${ABSL_CC_LIB_LINKOPTS}
284        ${ABSL_DEFAULT_LINKOPTS}
285    )
286    target_compile_definitions(${_NAME} INTERFACE ${ABSL_CC_LIB_DEFINES})
287  endif()
288
289  # TODO currently we don't install googletest alongside abseil sources, so
290  # installed abseil can't be tested.
291  if(NOT ABSL_CC_LIB_TESTONLY AND ABSL_ENABLE_INSTALL)
292    install(TARGETS ${_NAME} EXPORT ${PROJECT_NAME}Targets
293          RUNTIME DESTINATION ${ABSL_INSTALL_BINDIR}
294          LIBRARY DESTINATION ${ABSL_INSTALL_LIBDIR}
295          ARCHIVE DESTINATION ${ABSL_INSTALL_LIBDIR}
296    )
297  endif()
298
299    add_library(absl::${ABSL_CC_LIB_NAME} ALIAS ${_NAME})
300endfunction()
301
302# absl_cc_test()
303#
304# CMake function to imitate Bazel's cc_test rule.
305#
306# Parameters:
307# NAME: name of target (see Usage below)
308# SRCS: List of source files for the binary
309# DEPS: List of other libraries to be linked in to the binary targets
310# COPTS: List of private compile options
311# DEFINES: List of public defines
312# LINKOPTS: List of link options
313#
314# Note:
315# By default, absl_cc_test will always create a binary named absl_${NAME}.
316# This will also add it to ctest list as absl_${NAME}.
317#
318# Usage:
319# absl_cc_library(
320#   NAME
321#     awesome
322#   HDRS
323#     "a.h"
324#   SRCS
325#     "a.cc"
326#   PUBLIC
327# )
328#
329# absl_cc_test(
330#   NAME
331#     awesome_test
332#   SRCS
333#     "awesome_test.cc"
334#   DEPS
335#     absl::awesome
336#     gmock
337#     gtest_main
338# )
339function(absl_cc_test)
340  if(NOT ABSL_RUN_TESTS)
341    return()
342  endif()
343
344  cmake_parse_arguments(ABSL_CC_TEST
345    ""
346    "NAME"
347    "SRCS;COPTS;DEFINES;LINKOPTS;DEPS"
348    ${ARGN}
349  )
350
351  set(_NAME "absl_${ABSL_CC_TEST_NAME}")
352
353  add_executable(${_NAME} "")
354  target_sources(${_NAME} PRIVATE ${ABSL_CC_TEST_SRCS})
355  target_include_directories(${_NAME}
356    PUBLIC ${ABSL_COMMON_INCLUDE_DIRS}
357    PRIVATE ${GMOCK_INCLUDE_DIRS} ${GTEST_INCLUDE_DIRS}
358  )
359
360  if (${ABSL_BUILD_DLL})
361    target_compile_definitions(${_NAME}
362      PUBLIC
363        ${ABSL_CC_TEST_DEFINES}
364        ABSL_CONSUME_DLL
365        GTEST_LINKED_AS_SHARED_LIBRARY=1
366    )
367
368    # Replace dependencies on targets inside the DLL with abseil_dll itself.
369    absl_internal_dll_targets(
370      DEPS ${ABSL_CC_TEST_DEPS}
371      OUTPUT ABSL_CC_TEST_DEPS
372    )
373  else()
374    target_compile_definitions(${_NAME}
375      PUBLIC
376        ${ABSL_CC_TEST_DEFINES}
377    )
378  endif()
379  target_compile_options(${_NAME}
380    PRIVATE ${ABSL_CC_TEST_COPTS}
381  )
382
383  target_link_libraries(${_NAME}
384    PUBLIC ${ABSL_CC_TEST_DEPS}
385    PRIVATE ${ABSL_CC_TEST_LINKOPTS}
386  )
387  # Add all Abseil targets to a folder in the IDE for organization.
388  set_property(TARGET ${_NAME} PROPERTY FOLDER ${ABSL_IDE_FOLDER}/test)
389
390  set_property(TARGET ${_NAME} PROPERTY CXX_STANDARD ${ABSL_CXX_STANDARD})
391  set_property(TARGET ${_NAME} PROPERTY CXX_STANDARD_REQUIRED ON)
392
393  add_test(NAME ${_NAME} COMMAND ${_NAME})
394endfunction()
395
396
397function(check_target my_target)
398  if(NOT TARGET ${my_target})
399    message(FATAL_ERROR " ABSL: compiling absl requires a ${my_target} CMake target in your project,
400                   see CMake/README.md for more details")
401  endif(NOT TARGET ${my_target})
402endfunction()
403