premake: Introduce REVISION_CLEAN. More info in this commit msg.

REVISION_CLEAN can be 0 or 1. When it is 0 that means that there were uncommitted changes to the code at the time of version info generation, otherwise this will be 1 which means that there have been no uncommitted changes.

premake5.lua

@@ -33,8 +33,20 @@ newaction {
 		local revNumber = assert(proc:read('*a')):gsub("%s+", "")
 		proc:close()
 
+		-- get whether this is a clean revision (no uncommitted changes)
+		local proc = assert(io.popen("git status --porcelain", "r"))
+		local revClean = 1
+		local revCleanSuffix = ""
+		if assert(proc:read('*a')) ~= "" then
+			revClean = 0
+			revCleanSuffix = " (unclean)"
+		end
+		proc:close()
+
 		-- get old version number from version.hpp if any
 		local oldRevNumber = "(none)"
+		local oldRevClean = 1
+		local oldRevCleanSuffix = ""
 		local oldVersionHeader = io.open(wks.location .. "/src/version.hpp", "r")
 		if oldVersionHeader ~=nil then
 			local oldVersionHeaderContent = assert(oldVersionHeader:read('*a'))
@@ -43,11 +55,23 @@ newaction {
 				-- old version.hpp format?
 				oldRevNumber = "(none)"
 			end
+			oldRevClean = string.match(oldVersionHeaderContent, "#define REVISION_CLEAN (%d+)")
+			if oldRevClean == nil then
+				-- old version.hpp format?
+				oldRevClean = 1
+			elseif oldRevClean ~= "1" then
+				oldRevClean = 0
+			else
+				oldRevClean = 1
+			end
+		end
+		if oldRevClean == 0 then
+			oldRevCleanSuffix = " (unclean)"
 		end
 
 		-- generate version.hpp with a revision number if not equal
-		if oldRevNumber ~= revNumber then
-			print ("Update " .. oldRevNumber .. " -> " .. revNumber)
+		if oldRevNumber ~= revNumber or oldRevClean ~= revClean then
+			print ("Update " .. oldRevNumber .. oldRevCleanSuffix .. " -> " .. revNumber .. revCleanSuffix)
 			local versionHeader = assert(io.open(wks.location .. "/src/version.hpp", "w"))
 			versionHeader:write("/*\n")
 			versionHeader:write(" * Automatically generated by premake5.\n")
@@ -55,6 +79,7 @@ newaction {
 			versionHeader:write(" */\n")
 			versionHeader:write("\n")
 			versionHeader:write("#define REVISION " .. revNumber .. "\n")
+			versionHeader:write("#define REVISION_CLEAN " .. revClean .. "\n")
 			versionHeader:close()
 		end
 	end