From 9ce67d30011db4528d3d0bbee36412e13cfb80cc Mon Sep 17 00:00:00 2001
From: Tobias Bieniek <Tobias.Bieniek@gmx.de>
Date: Tue, 29 May 2012 17:45:03 +0200
Subject: [PATCH] Qt4Macros: Added support for generated resource files

Using the QT4_ADD_RESOURCES() macro required the resource file to exist
already for dependency scanning.  This prevented the use of resource
files that are generated by cmake because it needs the file before
resolving the dependency.  This patch adds support for generated
resource files by not scanning the resource file for dependencies if it
doesn't exist yet.  The add_custom_command() to generate the resource
file should add the dependencies on the files used by the resource file.
---
 Modules/Qt4Macros.cmake | 40 ++++++++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/Modules/Qt4Macros.cmake b/Modules/Qt4Macros.cmake
index f327125b2..f867bc51a 100644
--- a/Modules/Qt4Macros.cmake
+++ b/Modules/Qt4Macros.cmake
@@ -182,23 +182,31 @@ MACRO (QT4_ADD_RESOURCES outfiles )
     GET_FILENAME_COMPONENT(infile ${it} ABSOLUTE)
     GET_FILENAME_COMPONENT(rc_path ${infile} PATH)
     SET(outfile ${CMAKE_CURRENT_BINARY_DIR}/qrc_${outfilename}.cxx)
-    #  parse file for dependencies 
-    #  all files are absolute paths or relative to the location of the qrc file
-    FILE(READ "${infile}" _RC_FILE_CONTENTS)
-    STRING(REGEX MATCHALL "<file[^<]+" _RC_FILES "${_RC_FILE_CONTENTS}")
+
     SET(_RC_DEPENDS)
-    FOREACH(_RC_FILE ${_RC_FILES})
-      STRING(REGEX REPLACE "^<file[^>]*>" "" _RC_FILE "${_RC_FILE}")
-      IF(NOT IS_ABSOLUTE "${_RC_FILE}")
-        SET(_RC_FILE "${rc_path}/${_RC_FILE}")
-      ENDIF(NOT IS_ABSOLUTE "${_RC_FILE}")
-      SET(_RC_DEPENDS ${_RC_DEPENDS} "${_RC_FILE}")
-    ENDFOREACH(_RC_FILE)
-    # Since this cmake macro is doing the dependency scanning for these files,
-    # let's make a configured file and add it as a dependency so cmake is run
-    # again when dependencies need to be recomputed.
-    QT4_MAKE_OUTPUT_FILE("${infile}" "" "qrc.depends" out_depends)
-    CONFIGURE_FILE("${infile}" "${out_depends}" COPY_ONLY)
+    IF(EXISTS "${infile}")
+      #  parse file for dependencies
+      #  all files are absolute paths or relative to the location of the qrc file
+      FILE(READ "${infile}" _RC_FILE_CONTENTS)
+      STRING(REGEX MATCHALL "<file[^<]+" _RC_FILES "${_RC_FILE_CONTENTS}")
+      FOREACH(_RC_FILE ${_RC_FILES})
+        STRING(REGEX REPLACE "^<file[^>]*>" "" _RC_FILE "${_RC_FILE}")
+        IF(NOT IS_ABSOLUTE "${_RC_FILE}")
+          SET(_RC_FILE "${rc_path}/${_RC_FILE}")
+        ENDIF(NOT IS_ABSOLUTE "${_RC_FILE}")
+        SET(_RC_DEPENDS ${_RC_DEPENDS} "${_RC_FILE}")
+      ENDFOREACH(_RC_FILE)
+      # Since this cmake macro is doing the dependency scanning for these files,
+      # let's make a configured file and add it as a dependency so cmake is run
+      # again when dependencies need to be recomputed.
+      QT4_MAKE_OUTPUT_FILE("${infile}" "" "qrc.depends" out_depends)
+      CONFIGURE_FILE("${infile}" "${out_depends}" COPY_ONLY)
+    ELSE(EXISTS "${infile}")
+      # The .qrc file does not exist (yet). Let's add a dependency and hope
+      # that it will be generated later
+      SET(out_depends)
+    ENDIF(EXISTS "${infile}")
+
     ADD_CUSTOM_COMMAND(OUTPUT ${outfile}
       COMMAND ${QT_RCC_EXECUTABLE}
       ARGS ${rcc_options} -name ${outfilename} -o ${outfile} ${infile}