From 0e90645ac037ee278f2937454faca413c409d42b Mon Sep 17 00:00:00 2001
From: Raphael Dumusc <raphael.dumusc@epfl.ch>
Date: Wed, 31 May 2017 11:38:56 +0200
Subject: [PATCH] CommonGraph: improve graph output and options, fix recursion

New ${PROJECT_NAME}_IS_METAPROJECT option in SubProject.cmake to
generate graphs without a top-level item for meta-projects that
don't call common_find_package(), such as VizStable.
---
 CommonFindPackage.cmake |  22 ++++++-
 CommonGraph.cmake       | 141 +++++++++++++++++++++++++---------------
 SubProject.cmake        |  70 +++++++++++---------
 3 files changed, 145 insertions(+), 88 deletions(-)

diff --git a/CommonFindPackage.cmake b/CommonFindPackage.cmake
index a558c9f..975626d 100644
--- a/CommonFindPackage.cmake
+++ b/CommonFindPackage.cmake
@@ -85,8 +85,19 @@ macro(common_find_package Package_Name)
       ${__find_quiet})
   endif()
 
+  # Check find operation result and add graph dependency
+
+  if(${Package_Name}_IS_SUBPROJECT)
+    set(_is_subproject SOURCE)
+  else()
+    set(_is_subproject)
+  endif()
+
   if(__pkg_REQUIRED)  # required find
-    if((NOT ${Package_Name}_FOUND) AND (NOT ${PACKAGE_NAME}_FOUND))
+    if(${Package_Name}_FOUND OR ${PACKAGE_NAME}_FOUND)
+      common_graph_dep(${PROJECT_NAME} ${Package_Name} ${_is_subproject} REQUIRED)
+    else()
+      common_graph_dep(${PROJECT_NAME} ${Package_Name} ${_is_subproject} REQUIRED NOTFOUND)
       if(CMAKE_SOURCE_DIR STREQUAL PROJECT_SOURCE_DIR)
         message(FATAL_ERROR "Not configured ${PROJECT_NAME}: Required ${Package_Name} not found")
       else()
@@ -94,11 +105,16 @@ macro(common_find_package Package_Name)
       endif()
       return()
     endif()
-    common_graph_dep(${PROJECT_NAME} ${Package_Name} TRUE FALSE)
   else()  # optional find
-    common_graph_dep(${PROJECT_NAME} ${Package_Name} FALSE FALSE)
+    if(${Package_Name}_FOUND OR ${PACKAGE_NAME}_FOUND)
+      common_graph_dep(${PROJECT_NAME} ${Package_Name} ${_is_subproject})
+    else()
+      common_graph_dep(${PROJECT_NAME} ${Package_Name} ${_is_subproject} NOTFOUND)
+    endif()
   endif()
 
+  # Set common found variables, link and include directories
+
   if(${PACKAGE_NAME}_FOUND)
     set(${Package_Name}_name ${PACKAGE_NAME})
     set(${Package_Name}_FOUND TRUE)
diff --git a/CommonGraph.cmake b/CommonGraph.cmake
index 65c62ae..2e6c4bb 100644
--- a/CommonGraph.cmake
+++ b/CommonGraph.cmake
@@ -12,6 +12,7 @@
 # CMake options:
 # * COMMON_GRAPH_SHOW_EXTERNAL include external dependencies in graphs.
 # * COMMON_GRAPH_SHOW_OPTIONAL include optional dependencies in graphs.
+# * COMMON_GRAPH_SHOW_NOTFOUND include missing dependencies in graphs.
 #
 # Targets generated:
 # * graphs: generate .png graphs for all (sub)projects.
@@ -24,82 +25,116 @@ endif()
 set(COMMON_GRAPH_DONE ON)
 
 option(COMMON_GRAPH_SHOW_EXTERNAL "Include external dependencies in graphs" ON)
-option(COMMON_GRAPH_SHOW_OPTIONAL "Include optional dependencies in graphs" OFF)
+option(COMMON_GRAPH_SHOW_OPTIONAL "Include optional dependencies in graphs" ON)
+option(COMMON_GRAPH_SHOW_NOTFOUND "Include missing dependencies in graphs" ON)
 
 find_program(DOT_EXECUTABLE dot)
 find_program(TRED_EXECUTABLE tred)
 
-function(common_graph_dep From To Required Source)
+function(common_graph_dep From To)
+  # Parse function arguments
+  set(__options SOURCE REQUIRED NOTFOUND TOPLEVEL)
+  set(__oneValueArgs)
+  set(__multiValueArgs)
+  cmake_parse_arguments(__dep "${__options}" "${__oneValueArgs}" "${__multiValueArgs}" ${ARGN})
+
+  if(NOT __dep_SOURCE AND NOT COMMON_GRAPH_SHOW_EXTERNAL)
+    return()
+  endif()
+  if(NOT __dep_REQUIRED AND NOT COMMON_GRAPH_SHOW_OPTIONAL)
+    return()
+  endif()
+  if(__dep_NOTFOUND AND NOT COMMON_GRAPH_SHOW_NOTFOUND)
+    return()
+  endif()
+
   string(REPLACE "-" "_" Title ${From})
   string(REPLACE "-" "_" Dep ${To})
   # prevent syntax error in tred, e.g. Magick++ -> MagickPP
   string(REPLACE "+" "P" Title ${Title})
   string(REPLACE "+" "P" Dep ${Dep})
 
-  if(Source)
-    set(style "style=bold")
-  elseif(NOT COMMON_GRAPH_SHOW_EXTERNAL)
-    return()
-  elseif(Required)
-    set(style "style=solid")
-  elseif(COMMON_GRAPH_SHOW_OPTIONAL)
-    set(style "style=dashed")
+  if(__dep_SOURCE)
+    set(_style "style=bold")
+  elseif(__dep_REQUIRED)
+    set(_style "style=solid")
+  elseif(__dep_NOTFOUND)
+    set(_style "style=dotted")
   else()
-    return()
+    set(_style "style=dashed")
   endif()
 
-  set_property(GLOBAL APPEND_STRING PROPERTY ${From}_COMMON_GRAPH
-    "${Title} [label=\"${From}\"]\n")
-  if(Required)
+  if(__dep_NOTFOUND)
+    set(_linestyle "style=dotted")
+  elseif(__dep_SOURCE AND __dep_REQUIRED)
+    set(_linestyle "style=bold")
+  elseif(__dep_REQUIRED)
+    set(_linestyle "style=solid")
+  else()
+    set(_linestyle "style=dashed")
+  endif()
+
+  if(__dep_TOPLEVEL)
     set_property(GLOBAL APPEND_STRING PROPERTY ${From}_COMMON_GRAPH
-      "${Dep} [${style}, label=\"${To}\"]\n"
-      "\"${Dep}\" -> \"${Title}\" [${style}]\n" )
+      "${Dep} [${_style}, label=\"${To}\"]\n")
   else()
     set_property(GLOBAL APPEND_STRING PROPERTY ${From}_COMMON_GRAPH
-      "${Dep} [${style}, label=\"${To}\", fontsize=10]\n"
-      "\"${Dep}\" -> \"${Title}\" [${style}]\n" )
+      "${Title} [style=bold, label=\"${From}\"]\n"
+      "${Dep} [${_style}, label=\"${To}\"]\n"
+      "\"${Dep}\" -> \"${Title}\" [${_linestyle}]\n")
   endif()
   set_property(GLOBAL APPEND PROPERTY ${From}_COMMON_GRAPH_DEPENDS ${To})
 endfunction()
 
 function(common_graph Name)
-  # collect graph recursively
-  get_property(graph GLOBAL PROPERTY ${Name}_COMMON_GRAPH)
-  get_property(graph_depends GLOBAL PROPERTY ${Name}_COMMON_GRAPH_DEPENDS)
+  if(NOT DOT_EXECUTABLE OR NOT TRED_EXECUTABLE)
+    return()
+  endif()
 
-  list(LENGTH graph_depends nDepends)
+  # collect graph recursively for all dependencies of Name
+  get_property(_graph GLOBAL PROPERTY ${Name}_COMMON_GRAPH)
+  get_property(_dependencies GLOBAL PROPERTY ${Name}_COMMON_GRAPH_DEPENDS)
+  list(LENGTH _dependencies nDepends)
+
+  set(_loop_count 0)
   while(nDepends)
-    list(GET graph_depends 0 dep)
-    list(REMOVE_AT graph_depends 0)
-    get_property(graph_dep GLOBAL PROPERTY ${dep}_COMMON_GRAPH)
-    get_property(graph_dep_depends GLOBAL PROPERTY ${dep}_COMMON_GRAPH_DEPENDS)
-
-    set(graph "${graph_dep} ${graph}")
-    list(APPEND graph_dep ${graph_dep_depends})
-    list(LENGTH graph_depends nDepends)
+    list(GET _dependencies 0 dep)
+    list(REMOVE_AT _dependencies 0)
+
+    get_property(_dep_graph GLOBAL PROPERTY ${dep}_COMMON_GRAPH)
+    set(_graph "${_dep_graph} ${_graph}")
+
+    get_property(_dep_depends GLOBAL PROPERTY ${dep}_COMMON_GRAPH_DEPENDS)
+    list(APPEND _dependencies ${_dep_depends})
+    list(LENGTH _dependencies nDepends)
+
+    # prevent infinite looping in the case of circular dependencies
+    MATH(EXPR _loop_count "${_loop_count}+1")
+    if(_loop_count GREATER 1000)
+      message(WARNING "CommonGraph detected a probable circular dependency")
+      return()
+    endif()
   endwhile()
 
-  if(DOT_EXECUTABLE AND TRED_EXECUTABLE)
-    set(_dot_file ${CMAKE_CURRENT_BINARY_DIR}/${Name}.dot)
-    file(GENERATE OUTPUT ${_dot_file}
-      CONTENT "strict digraph G { rankdir=\"RL\"; ${graph} }")
-
-    set(_tred_dot_file ${CMAKE_CURRENT_BINARY_DIR}/${Name}_tred.dot)
-    add_custom_command(OUTPUT ${_tred_dot_file}
-      COMMAND ${TRED_EXECUTABLE} ${_dot_file} > ${_tred_dot_file}
-      DEPENDS ${_dot_file})
-
-    set(_image_folder ${PROJECT_BINARY_DIR}/doc/images)
-    set(_image_file ${_image_folder}/${Name}.png)
-    add_custom_command(OUTPUT ${_image_file}
-      COMMAND ${CMAKE_COMMAND} -E make_directory ${_image_folder}
-      COMMAND ${DOT_EXECUTABLE} -o ${_image_file} -Tpng ${_tred_dot_file}
-      DEPENDS ${_tred_dot_file})
-
-    add_custom_target(${Name}-graph DEPENDS ${_image_file})
-    set_target_properties(${Name}-graph PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD ON
-      FOLDER ${Name}/doxygen)
-    common_target(graphs doxygen)
-    add_dependencies(graphs ${Name}-graph)
-  endif()
+  set(_dot_file ${CMAKE_CURRENT_BINARY_DIR}/${Name}.dot)
+  file(GENERATE OUTPUT ${_dot_file}
+    CONTENT "strict digraph G { rankdir=\"RL\"; ${_graph} }")
+
+  set(_tred_dot_file ${CMAKE_CURRENT_BINARY_DIR}/${Name}_tred.dot)
+  add_custom_command(OUTPUT ${_tred_dot_file}
+    COMMAND ${TRED_EXECUTABLE} ${_dot_file} > ${_tred_dot_file}
+    DEPENDS ${_dot_file})
+
+  set(_image_folder ${PROJECT_BINARY_DIR}/doc/images)
+  set(_image_file ${_image_folder}/${Name}.png)
+  add_custom_command(OUTPUT ${_image_file}
+    COMMAND ${CMAKE_COMMAND} -E make_directory ${_image_folder}
+    COMMAND ${DOT_EXECUTABLE} -o ${_image_file} -Tpng ${_tred_dot_file}
+    DEPENDS ${_tred_dot_file})
+
+  add_custom_target(${Name}-graph DEPENDS ${_image_file})
+  set_target_properties(${Name}-graph PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD ON
+    FOLDER ${Name}/doxygen)
+  common_target(graphs doxygen)
+  add_dependencies(graphs ${Name}-graph)
 endfunction()
diff --git a/SubProject.cmake b/SubProject.cmake
index fae1d66..93e91a9 100644
--- a/SubProject.cmake
+++ b/SubProject.cmake
@@ -39,6 +39,8 @@
 # - SUBPROJECT_${name}: If set to OFF, the subproject is not added.
 # - COMMON_SOURCE_DIR: When set, the source code of subprojects will be
 #   downloaded in this path instead of CMAKE_SOURCE_DIR.
+# - ${PROJECT_NAME}_IS_METAPROJECT: Enable CommonGraph compatibility for a
+#   top-level project which does not use common_find_package().
 # A sample project can be found at https://github.com/Eyescale/Collage.git
 #
 # How to create a dependency graph:
@@ -86,8 +88,6 @@ function(add_subproject name)
       "cmake -DCLONE_SUBPROJECTS=ON\n"
       "to git-clone it automatically.")
   endif()
-  # enter again to catch direct add_subproject() calls
-  common_graph_dep(${PROJECT_NAME} ${name} TRUE TRUE)
 
   # allow exclusion of subproject via set(SUBPROJECT_${name} OFF)
   if(DEFINED SUBPROJECT_${name} AND NOT SUBPROJECT_${name})
@@ -111,9 +111,7 @@ function(add_subproject name)
 
   # add the source sub directory to our build and set the binary dir
   # to the build tree
-
-  add_subdirectory("${path}"
-    "${CMAKE_BINARY_DIR}/${name}")
+  add_subdirectory("${path}" "${CMAKE_BINARY_DIR}/${name}")
   set(${name}_IS_SUBPROJECT ON PARENT_SCOPE)
 
   # Mark globally that we've already used name as a sub project
@@ -121,36 +119,41 @@ function(add_subproject name)
 endfunction()
 
 macro(git_subproject name url tag)
-  # enter early to catch all dependencies
-  common_graph_dep(${PROJECT_NAME} ${name} TRUE TRUE)
-  if(NOT DISABLE_SUBPROJECTS)
-    string(TOUPPER ${name} NAME)
-    if(NOT ${NAME}_FOUND AND NOT ${name}_FOUND)
-      get_property(__included GLOBAL PROPERTY ${name}_IS_SUBPROJECT)
-      if(NOT __included)
-        if(NOT EXISTS ${__common_source_dir}/${name})
-          # Always try first using Config mode, then Module mode.
-          find_package(${name} QUIET CONFIG)
-          if(NOT ${NAME}_FOUND AND NOT ${name}_FOUND)
-            find_package(${name} QUIET MODULE)
-          endif()
+  if(DISABLE_SUBPROJECTS)
+    return()
+  endif()
+
+  # add graph dependency for meta-projects with no common_find_package() calls
+  if(${PROJECT_NAME}_IS_METAPROJECT)
+    common_graph_dep(${PROJECT_NAME} ${name} SOURCE TOPLEVEL REQUIRED)
+  endif()
+
+  string(TOUPPER ${name} NAME)
+  if(NOT ${NAME}_FOUND AND NOT ${name}_FOUND)
+    get_property(__included GLOBAL PROPERTY ${name}_IS_SUBPROJECT)
+    if(NOT __included)
+      if(NOT EXISTS ${__common_source_dir}/${name})
+        # Always try first using Config mode, then Module mode.
+        find_package(${name} QUIET CONFIG)
+        if(NOT ${NAME}_FOUND AND NOT ${name}_FOUND)
+          find_package(${name} QUIET MODULE)
         endif()
-        if((NOT ${NAME}_FOUND AND NOT ${name}_FOUND) OR
-            ${NAME}_FOUND_SUBPROJECT)
-          # not found externally, add as sub project
-          if(CLONE_SUBPROJECTS)
-            git_external(${__common_source_dir}/${name} ${url} ${tag})
-          endif()
-          add_subproject(${name})
+      endif()
+      if((NOT ${NAME}_FOUND AND NOT ${name}_FOUND) OR
+          ${NAME}_FOUND_SUBPROJECT)
+        # not found externally, add as sub project
+        if(CLONE_SUBPROJECTS)
+          git_external(${__common_source_dir}/${name} ${url} ${tag})
         endif()
+        add_subproject(${name})
       endif()
     endif()
-    get_property(__included GLOBAL PROPERTY ${name}_IS_SUBPROJECT)
-    if(__included)
-      list(APPEND __subprojects "${name} ${url} ${tag}")
-      if(TARGET ${PROJECT_NAME}-install AND TARGET ${name}-install)
-        add_dependencies(${PROJECT_NAME}-install ${name}-install)
-      endif()
+  endif()
+  get_property(__included GLOBAL PROPERTY ${name}_IS_SUBPROJECT)
+  if(__included)
+    list(APPEND __subprojects "${name} ${url} ${tag}")
+    if(TARGET ${PROJECT_NAME}-install AND TARGET ${name}-install)
+      add_dependencies(${PROJECT_NAME}-install ${name}-install)
     endif()
   endif()
 endmacro()
@@ -204,6 +207,9 @@ if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/.gitsubprojects")
       set_target_properties(update PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD ON)
     endif()
     add_dependencies(update ${PROJECT_NAME}-update-gitsubprojects)
-  endif()
 
+    if(${PROJECT_NAME}_IS_METAPROJECT)
+      common_graph(${PROJECT_NAME})
+    endif()
+  endif()
 endif()