Add generic support extended conditional syntax

extended conditionals use a syntax of
    cond=value
    cond=(value1 value2)
    cond=(value1,value2)
  where the comma is optional and supported as such because the
  flags syntax used them

  The mount patch extends, and improves on this patch, the changes probably
  should have been separated out but ...

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>

parser/parser_lex.l

@@ -213,6 +213,7 @@ ARROW		->
 LT_EQUAL	<=
 
 %x SUB_NAME
+%x EXTCOND_MODE
 %x NETWORK_MODE
 %x LIST_VAL_MODE
 %x ASSIGN_MODE
@@ -306,6 +307,34 @@ LT_EQUAL	<=
 			}
 }
 
+<EXTCOND_MODE>{
+	{WS}+		{ DUMP_PREPROCESS; /* Eat whitespace */ }
+
+	{EQUALS}	{
+			DUMP_PREPROCESS;
+			return TOK_EQUALS;
+		}
+
+	{OPEN_PAREN}	{
+			DUMP_PREPROCESS;
+			PDEBUG("extcond listv\n");
+			/* Don't push state here as this is a transition
+			 * start condition and we want to return to the start
+			 * condition that invoked <EXTCOND_MODE> when
+			 * SUB_NAME is done
+			 */
+			BEGIN(LIST_VAL_MODE);
+			return TOK_OPENPAREN;
+		}
+
+	[^\n]	{
+			DUMP_PREPROCESS;
+			/* Something we didn't expect */
+			yyerror(_("Found unexpected character: '%s'"), yytext);
+		}
+
+}
+
 <ASSIGN_MODE>{
 	{WS}+		{ DUMP_PREPROCESS; /* Eat whitespace */ }
 
@@ -536,6 +565,18 @@ LT_EQUAL	<=
 			return TOK_OPENPAREN;
 			}
 
+{VARIABLE_NAME}/{WS}*={WS}*	{
+				/* we match to the = in the lexer so that
+				 * can switch scanner state.  By the time
+				 * the parser see the = it may be to late
+				 * as bison may have requested the next
+				 * token from the scanner
+				 */
+				yylval.id = processid(yytext, yyleng);
+				yy_push_state(EXTCOND_MODE);
+				return TOK_CONDID;
+			}
+
 {VARIABLE_NAME}		{
 			DUMP_PREPROCESS;
 			int token = get_keyword_token(yytext);

parser/parser_yacc.y

@@ -78,6 +78,7 @@ void add_local_entry(struct codomain *cod);
 %}
 
 %token TOK_ID
+%token TOK_CONDID
 %token TOK_CARET
 %token TOK_OPEN
 %token TOK_CLOSE