FindPkgConfig: split args if loaded from environment

It's common for some people to use the PKG_CONFIG environment variable
to not only load a custom pkg-config/pkgconf but also to load some
default arguments such as `--static` or `--keep-system-libs` which often
worked since shell scripts would call `$PKG_CONFIG --libs pkg` without
quotes, but this breaks FindPkgConfig since it uses the full string as
`argv[0]` and might try looking for a binary called `pkgconf --static`,
instead of looking for `pkgconf` and adding `--static` as the `argv[1]`

Additionally adds RunCMake.FindPkgConfig ARGN test case

Fixes: #22305
Signed-off-by: Christopher Degawa <ccom@randomderp.com>

1 files changed, 34 insertions, 5 deletions

diff --git a/Modules/FindPkgConfig.cmake b/Modules/FindPkgConfig.cmake
index 3bc9dba..bd54fd9 100644
--- a/Modules/FindPkgConfig.cmake
+++ b/Modules/FindPkgConfig.cmake
@@ -15,6 +15,8 @@ following variables will also be set:
   if pkg-config executable was found
 ``PKG_CONFIG_EXECUTABLE``
   pathname of the pkg-config program
+``PKG_CONFIG_ARGN``
+  list of arguments to pass to pkg-config
 ``PKG_CONFIG_VERSION_STRING``
   version of pkg-config (since CMake 2.8.8)
 
@@ -29,7 +31,15 @@ set(PKG_CONFIG_VERSION 1)
 
 # find pkg-config, use PKG_CONFIG if set
 if((NOT PKG_CONFIG_EXECUTABLE) AND (NOT "$ENV{PKG_CONFIG}" STREQUAL ""))
-  set(PKG_CONFIG_EXECUTABLE "$ENV{PKG_CONFIG}" CACHE FILEPATH "pkg-config executable")
+  separate_arguments(PKG_CONFIG_FROM_ENV_SPLIT NATIVE_COMMAND PROGRAM SEPARATE_ARGS "$ENV{PKG_CONFIG}")
+  list(LENGTH PKG_CONFIG_FROM_ENV_SPLIT PKG_CONFIG_FROM_ENV_SPLIT_ARGC)
+  if(PKG_CONFIG_FROM_ENV_SPLIT_ARGC GREATER 0)
+    list(GET PKG_CONFIG_FROM_ENV_SPLIT 0 PKG_CONFIG_FROM_ENV_ARGV0)
+    if(PKG_CONFIG_FROM_ENV_SPLIT_ARGC GREATER 1)
+      list(SUBLIST PKG_CONFIG_FROM_ENV_SPLIT 1 -1 PKG_CONFIG_ARGN)
+    endif()
+    set(PKG_CONFIG_EXECUTABLE "${PKG_CONFIG_FROM_ENV_ARGV0}" CACHE FILEPATH "pkg-config executable")
+  endif()
 endif()
 
 set(PKG_CONFIG_NAMES "pkg-config")
@@ -43,9 +53,12 @@ find_program(PKG_CONFIG_EXECUTABLE
   DOC "pkg-config executable")
 mark_as_advanced(PKG_CONFIG_EXECUTABLE)
 
+set(PKG_CONFIG_ARGN "${PKG_CONFIG_ARGN}" CACHE STRING "Arguments to supply to pkg-config")
+mark_as_advanced(PKG_CONFIG_ARGN)
+
 set(_PKG_CONFIG_FAILURE_MESSAGE "")
 if (PKG_CONFIG_EXECUTABLE)
-  execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE} --version
+  execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE} ${PKG_CONFIG_ARGN} --version
     OUTPUT_VARIABLE PKG_CONFIG_VERSION_STRING OUTPUT_STRIP_TRAILING_WHITESPACE
     ERROR_VARIABLE _PKG_CONFIG_VERSION_ERROR ERROR_STRIP_TRAILING_WHITESPACE
     RESULT_VARIABLE _PKG_CONFIG_VERSION_RESULT
@@ -53,14 +66,18 @@ if (PKG_CONFIG_EXECUTABLE)
 
   if (NOT _PKG_CONFIG_VERSION_RESULT EQUAL 0)
     string(REPLACE "\n" "\n    " _PKG_CONFIG_VERSION_ERROR "      ${_PKG_CONFIG_VERSION_ERROR}")
+    if(PKG_CONFIG_ARGN)
+      string(REPLACE ";" " " PKG_CONFIG_ARGN " ${PKG_CONFIG_ARGN}")
+    endif()
     string(APPEND _PKG_CONFIG_FAILURE_MESSAGE
       "The command\n"
-      "      \"${PKG_CONFIG_EXECUTABLE}\" --version\n"
+      "      \"${PKG_CONFIG_EXECUTABLE}\"${PKG_CONFIG_ARGN} --version\n"
       "    failed with output:\n${PKG_CONFIG_VERSION_STRING}\n"
       "    stderr: \n${_PKG_CONFIG_VERSION_ERROR}\n"
       "    result: \n${_PKG_CONFIG_VERSION_RESULT}"
       )
     set(PKG_CONFIG_EXECUTABLE "")
+    set(PKG_CONFIG_ARGN "")
     unset(PKG_CONFIG_VERSION_STRING)
   endif ()
   unset(_PKG_CONFIG_VERSION_RESULT)
@@ -91,7 +108,7 @@ macro(_pkgconfig_invoke _pkglist _prefix _varname _regexp)
   set(_pkgconfig_invoke_result)
 
   execute_process(
-    COMMAND ${PKG_CONFIG_EXECUTABLE} ${ARGN} ${_pkglist}
+    COMMAND ${PKG_CONFIG_EXECUTABLE} ${PKG_CONFIG_ARGN} ${ARGN} ${_pkglist}
     OUTPUT_VARIABLE _pkgconfig_invoke_result
     RESULT_VARIABLE _pkgconfig_failed
     OUTPUT_STRIP_TRAILING_WHITESPACE)
@@ -533,7 +550,7 @@ macro(_pkg_check_modules_internal _is_required _is_silent _no_cmake_path _no_cma
 
       # execute the query
       execute_process(
-        COMMAND ${PKG_CONFIG_EXECUTABLE} ${_pkg_check_modules_exist_query}
+        COMMAND ${PKG_CONFIG_EXECUTABLE} ${PKG_CONFIG_ARGN} ${_pkg_check_modules_exist_query}
         RESULT_VARIABLE _pkgconfig_retval
         ERROR_VARIABLE _pkgconfig_error
         ERROR_STRIP_TRAILING_WHITESPACE)
@@ -892,6 +909,18 @@ Variables Affecting Behavior
   .. versionadded:: 3.1
     The ``PKG_CONFIG`` environment variable can be used as a hint.
 
+.. variable:: PKG_CONFIG_ARGN
+
+  .. versionadded:: 3.22
+
+  This can be set to a list of arguments to additionally pass to pkg-config
+  if needed. If not provided, it will be an empty string, however, if the
+  environment variable ``PKG_CONFIG`` is provided, this will be set to the
+  result of splitting the variable.
+
+  The ``PKG_CONFIG`` environment variable can be used to provide both
+  ``PKG_CONFIG_EXECUTABLE`` and ``PKG_CONFIG_ARGN``
+
 .. variable:: PKG_CONFIG_USE_CMAKE_PREFIX_PATH
 
   .. versionadded:: 3.1