From e59516950193f9dea1b903c9fcd5e6091f9bcb70 Mon Sep 17 00:00:00 2001
From: ccremers <ccremers@4f7d145f-a0d4-0310-ae10-d96cc04433c1>
Date: Mon, 8 Jan 2007 06:17:10 +0000
Subject: [PATCH] - Improved svnversion writes.

---
 src/SVNVersion.cmake | 53 ++++++++++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 14 deletions(-)

diff --git a/src/SVNVersion.cmake b/src/SVNVersion.cmake
index 1e476b0..fcc3b60 100644
--- a/src/SVNVersion.cmake
+++ b/src/SVNVersion.cmake
@@ -14,20 +14,45 @@ set_source_files_properties(version.h
 	GENERATED true)
 find_program (SVNVERSION_EXECUTABLE NAMES svnversion)
 mark_as_advanced (SVNVERSION_EXECUTABLE)
+mark_as_advanced (SVNVERSION_DYNAMIC)
+set (SVNVERSION_DYNAMIC false)
 if (SVNVERSION_EXECUTABLE)
-	# svnversion found; we should always build this
-	mark_as_advanced (SVN_Version)
-	message (STATUS "Generating version.h using svnversion command")
-	exec_program (${SVNVERSION_EXECUTABLE}
-		OUTPUT_VARIABLE SVN_Version
-	)
-	message (STATUS "svnversion gave ${SVN_Version}")
-	file (WRITE version.h
-		"#define SVNVERSION \"${SVN_Version}\"\n"
-	)
-else (SVNVERSION_EXECUTABLE)
-	# No svnversion. what do we write then? just empty...?
-	message (STATUS "Generating empty version.h")
-	file (WRITE version.h "")
+	# svnversion found
+	if (UNIX)
+		# Unix system
+		# test whether svnversion gives useful info
+		exec_program (${SVNVERSION_EXECUTABLE}
+			OUTPUT_VALUE SVN_Result
+		)
+		mark_as_advanced (SVN_Result)
+		if (SVN_Result STREQUAL "exported")
+			# svnversion gives useful stuff
+			set (SVNVERSION_DYNAMIC true)
+		endif (SVN_Result STREQUAL "exported")
+		mark_as_advanced (SVNDIR)
+	endif (UNIX)
 endif (SVNVERSION_EXECUTABLE)
 
+if (SVNVERSION_DYNAMIC)
+	# add a command to generate version.h
+	message (STATUS	"Generating version.h dynamically using svnversion command")
+	add_custom_command (
+		OUTPUT	version.h
+		# The version number depends on all the files; if they
+		# don't change, neither should the version number
+		# (although this might be incorrect when updating the
+		# current directory)
+		DEPENDS	${Scyther_sources}
+		DEPENDS .svn
+		COMMAND	echo
+		ARGS	"\\#define SVNVERSION \\\"`${SVNVERSION_EXECUTABLE}`\\\"" >version.h
+		COMMENT	"Generating subversion version information in version.h using svnversion command"
+	)
+else (SVNVERSION_DYNAMIC)
+	# Don't dynamically generate, simply empty every time
+	file (WRITE version.h "#define SVNVERSION \"Unknown\"\n")
+endif (SVNVERSION_DYNAMIC)
+
+# add the version number to the sources
+set (Scyther_sources ${Scyther_sources} version.h)
+