public: build: split Q_buildnum to separate function that calculates build number from arbitrary date string

public/build.c

@@ -16,27 +16,16 @@ GNU General Public License for more details.
 #include "crtlib.h"
 #include "buildenums.h"
 
-static const char *date = __DATE__ ;
 static const char *mon[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
 static const char mond[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
 
-/*
-===============
-Q_buildnum
-
-returns days since Apr 1 2015
-===============
-*/
-int Q_buildnum( void )
+int Q_buildnum_date( const char *date )
 {
-	static int b = 0;
+	int b;
 	int m = 0;
 	int d = 0;
 	int y = 0;
 
-	if( b != 0 )
-		return b;
-
 	for( m = 0; m < 11; m++ )
 	{
 		if( !Q_strnicmp( &date[0], mon[m], 3 ))
@@ -57,6 +46,23 @@ int Q_buildnum( void )
 	return b;
 }
 
+/*
+===============
+Q_buildnum
+
+returns days since Apr 1 2015
+===============
+*/
+int Q_buildnum( void )
+{
+	static int b = 0;
+
+	if( !b )
+		b = Q_buildnum_date( __DATE__ );
+
+	return b;
+}
+
 /*
 =============
 Q_buildnum_compat

public/crtlib.h

@@ -48,6 +48,7 @@ enum
 // build.c
 //
 int Q_buildnum( void );
+int Q_buildnum_date( const char *date );
 int Q_buildnum_compat( void );
 const char *Q_PlatformStringByID( const int platform );
 const char *Q_buildos( void );