[cmake] FindFmt module enable_internal to check existing lib

enables the ENABLE_INTERNAL_FMT path to test for existing lib/package and if it meets
the version supplied by FMT-VERSION, we dont need to rebuild.

1 files changed, 83 insertions, 66 deletions

diff --git a/cmake/modules/FindFmt.cmake b/cmake/modules/FindFmt.cmake
index fa5f1c585c..a6e811eb5a 100644
--- a/cmake/modules/FindFmt.cmake
+++ b/cmake/modules/FindFmt.cmake
@@ -12,91 +12,108 @@
 #
 #   fmt::fmt   - The Fmt library
 
-if(ENABLE_INTERNAL_FMT)
-  include(cmake/scripts/common/ModuleHelpers.cmake)
+# If target exists, no need to rerun find
+# Allows a module that may be a dependency for multiple libraries to just be executed
+# once to populate all required variables/targets
+if(NOT TARGET fmt::fmt)
+  if(ENABLE_INTERNAL_FMT)
 
-  set(MODULE_LC fmt)
+    include(cmake/scripts/common/ModuleHelpers.cmake)
 
-  SETUP_BUILD_VARS()
+    set(MODULE_LC fmt)
 
-  if(APPLE)
-    set(EXTRA_ARGS "-DCMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}")
-  endif()
+    SETUP_BUILD_VARS()
 
-  set(FMT_VERSION ${${MODULE}_VER})
+    # Check for existing FMT. If version >= FMT-VERSION file version, dont build
+    find_package(FMT CONFIG QUIET)
 
-  if(WIN32 OR WINDOWS_STORE)
-    # find the path to the patch executable
-    find_package(Patch MODULE REQUIRED)
+    if(FMT_VERSION VERSION_LESS ${${MODULE}_VER})
 
-    set(patch ${CMAKE_SOURCE_DIR}/tools/depends/target/${MODULE_LC}/001-windows-pdb-symbol-gen.patch)
-    PATCH_LF_CHECK(${patch})
+      if(APPLE)
+        set(EXTRA_ARGS "-DCMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}")
+      endif()
 
-    set(PATCH_COMMAND ${PATCH_EXECUTABLE} -p1 -i ${patch})
-  endif()
+      set(FMT_VERSION ${${MODULE}_VER})
 
-  set(CMAKE_ARGS -DCMAKE_CXX_EXTENSIONS=${CMAKE_CXX_EXTENSIONS}
-                 -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
-                 -DFMT_DOC=OFF
-                 -DFMT_TEST=OFF
-                 -DFMT_INSTALL=ON
-                 "${EXTRA_ARGS}")
+      if(WIN32 OR WINDOWS_STORE)
+        # find the path to the patch executable
+        find_package(Patch MODULE REQUIRED)
 
-  # fmt debug uses postfix d for all platforms
-  set(FMT_DEBUG_POSTFIX d)
+        set(patch ${CMAKE_SOURCE_DIR}/tools/depends/target/${MODULE_LC}/001-windows-pdb-symbol-gen.patch)
+        PATCH_LF_CHECK(${patch})
 
-  BUILD_DEP_TARGET()
-else()
-  find_package(FMT 6.1.2 CONFIG REQUIRED QUIET)
+        set(PATCH_COMMAND ${PATCH_EXECUTABLE} -p1 -i ${patch})
+      endif()
 
-  if(PKG_CONFIG_FOUND)
-    pkg_check_modules(PC_FMT libfmt QUIET)
-    if(PC_FMT_VERSION AND NOT FMT_VERSION)
-      set(FMT_VERSION ${PC_FMT_VERSION})
-    endif()
-  endif()
+      set(CMAKE_ARGS -DCMAKE_CXX_EXTENSIONS=${CMAKE_CXX_EXTENSIONS}
+                     -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
+                     -DFMT_DOC=OFF
+                     -DFMT_TEST=OFF
+                     -DFMT_INSTALL=ON
+                     "${EXTRA_ARGS}")
 
-  find_path(FMT_INCLUDE_DIR NAMES fmt/format.h
-                            PATHS ${PC_FMT_INCLUDEDIR})
+      # fmt debug uses postfix d for all platforms
+      set(FMT_DEBUG_POSTFIX d)
 
-  find_library(FMT_LIBRARY_RELEASE NAMES fmt
-                                  PATHS ${PC_FMT_LIBDIR})
-  find_library(FMT_LIBRARY_DEBUG NAMES fmtd
-                                 PATHS ${PC_FMT_LIBDIR})
-
-endif()
+      BUILD_DEP_TARGET()
+    else()
+      # Populate paths for find_package_handle_standard_args
+      find_path(FMT_INCLUDE_DIR NAMES fmt/format.h)
+      find_library(FMT_LIBRARY_RELEASE NAMES fmt)
+      find_library(FMT_LIBRARY_DEBUG NAMES fmtd)
+    endif()
+  else()
+    find_package(FMT 6.1.2 CONFIG REQUIRED QUIET)
+
+    if(PKG_CONFIG_FOUND)
+      pkg_check_modules(PC_FMT libfmt QUIET)
+      if(PC_FMT_VERSION AND NOT FMT_VERSION)
+        set(FMT_VERSION ${PC_FMT_VERSION})
+      endif()
+    endif()
 
-include(SelectLibraryConfigurations)
-select_library_configurations(FMT)
+    find_path(FMT_INCLUDE_DIR NAMES fmt/format.h
+                              PATHS ${PC_FMT_INCLUDEDIR})
 
-include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(Fmt
-                                  REQUIRED_VARS FMT_LIBRARY FMT_INCLUDE_DIR
-                                  VERSION_VAR FMT_VERSION)
+    find_library(FMT_LIBRARY_RELEASE NAMES fmt
+                                    PATHS ${PC_FMT_LIBDIR})
+    find_library(FMT_LIBRARY_DEBUG NAMES fmtd
+                                   PATHS ${PC_FMT_LIBDIR})
 
-if(FMT_FOUND)
-  set(FMT_LIBRARIES ${FMT_LIBRARY})
-  set(FMT_INCLUDE_DIRS ${FMT_INCLUDE_DIR})
+  endif()
 
-  if(NOT TARGET fmt::fmt)
-    add_library(fmt::fmt UNKNOWN IMPORTED)
-    if(FMT_LIBRARY_RELEASE)
+  include(SelectLibraryConfigurations)
+  select_library_configurations(FMT)
+
+  include(FindPackageHandleStandardArgs)
+  find_package_handle_standard_args(Fmt
+                                    REQUIRED_VARS FMT_LIBRARY FMT_INCLUDE_DIR
+                                    VERSION_VAR FMT_VERSION)
+
+  if(FMT_FOUND)
+    set(FMT_LIBRARIES ${FMT_LIBRARY})
+    set(FMT_INCLUDE_DIRS ${FMT_INCLUDE_DIR})
+
+    if(NOT TARGET fmt::fmt)
+      add_library(fmt::fmt UNKNOWN IMPORTED)
+      if(FMT_LIBRARY_RELEASE)
+        set_target_properties(fmt::fmt PROPERTIES
+                                       IMPORTED_CONFIGURATIONS RELEASE
+                                       IMPORTED_LOCATION "${FMT_LIBRARY_RELEASE}")
+      endif()
+      if(FMT_LIBRARY_DEBUG)
+        set_target_properties(fmt::fmt PROPERTIES
+                                       IMPORTED_CONFIGURATIONS DEBUG
+                                       IMPORTED_LOCATION "${FMT_LIBRARY_DEBUG}")
+      endif()
       set_target_properties(fmt::fmt PROPERTIES
-                                     IMPORTED_CONFIGURATIONS RELEASE
-                                     IMPORTED_LOCATION "${FMT_LIBRARY_RELEASE}")
+                                     INTERFACE_INCLUDE_DIRECTORIES "${FMT_INCLUDE_DIR}")
     endif()
-    if(FMT_LIBRARY_DEBUG)
-      set_target_properties(fmt::fmt PROPERTIES
-                                     IMPORTED_CONFIGURATIONS DEBUG
-                                     IMPORTED_LOCATION "${FMT_LIBRARY_DEBUG}")
+    if(TARGET fmt)
+      add_dependencies(fmt::fmt fmt)
     endif()
-    set_target_properties(fmt::fmt PROPERTIES
-                                   INTERFACE_INCLUDE_DIRECTORIES "${FMT_INCLUDE_DIR}")
+    set_property(GLOBAL APPEND PROPERTY INTERNAL_DEPS_PROP fmt::fmt)
   endif()
-  if(TARGET fmt)
-    add_dependencies(fmt::fmt fmt)
-  endif()
-  set_property(GLOBAL APPEND PROPERTY INTERNAL_DEPS_PROP fmt::fmt)
-endif()
 
-mark_as_advanced(FMT_INCLUDE_DIR FMT_LIBRARY)
+  mark_as_advanced(FMT_INCLUDE_DIR FMT_LIBRARY)
+endif()