ash: fix arithmetic closing )) split by backslash-newline

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

shell/ash.c

@@ -11437,7 +11437,7 @@ readtoken1(int c, int syntax, char *eofmark, int striptabs)
 			if (parenlevel > 0) {
 				parenlevel--;
 			} else {
-				if (pgetc() == ')') {
+				if (pgetc_eatbnl() == ')') {
 					c = CTLENDARI;
 					if (--arinest == 0) {
 						syntax = prevsyntax;
@@ -11464,6 +11464,7 @@ readtoken1(int c, int syntax, char *eofmark, int striptabs)
 			if (varnest == 0) {
 #if ENABLE_ASH_BASH_COMPAT
 				if (c == '&') {
+//Can't call pgetc_eatbnl() here, this requires three-deep pungetc()
 					if (pgetc() == '>')
 						c = 0x100 + '>'; /* flag &> */
 					pungetc();

shell/ash_test/ash-vars/var_unbackslash1.right

@@ -1,3 +1,7 @@
 Ok
 Ba d
 Ok
+Ok
+Ok
+Forty two:42
+Forty two:42

shell/ash_test/ash-vars/var_unbackslash1.tests

@@ -13,3 +13,23 @@ d'
 eval $e
 # "Ok"
 eval "$e"
+
+echo $\
+(echo Ok\
+)
+echo "$\
+(echo Ok\
+)"
+
+echo Forty two:$\
+(\
+(\
+42\
+)\
+)
+echo "Forty two:$\
+(\
+(\
+42\
+)\
+)"

shell/hush_test/hush-vars/var_unbackslash1.right

@@ -1,3 +1,7 @@
 Ok
 Ba d
 Ok
+Ok
+Ok
+Forty two:42
+Forty two:42

shell/hush_test/hush-vars/var_unbackslash1.tests

@@ -13,3 +13,23 @@ d'
 eval $e
 # "Ok"
 eval "$e"
+
+echo $\
+(echo Ok\
+)
+echo "$\
+(echo Ok\
+)"
+
+echo Forty two:$\
+(\
+(\
+42\
+)\
+)
+echo "Forty two:$\
+(\
+(\
+42\
+)\
+)"