hush: never glob result of dquoted "${v:+/bin/c*}"

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

shell/ash_test/ash-glob/glob_altvalue1.right

@@ -0,0 +1,7 @@
+1u: glob_altvalue1.tests
+2u: glob_altvalue1.t*
+3u: glob_altvalue1.t*
+4u: glob_altvalue1.t*
+1q: glob_altvalue1.t*
+2q: 'glob_altvalue1.t*'
+3q: glob_altvalue1.t*

shell/ash_test/ash-glob/glob_altvalue1.tests

@@ -0,0 +1,13 @@
+x=x
+
+echo 1u: ${x:+glob_altvalue1.t*}
+echo 2u: ${x:+'glob_altvalue1.t*'}
+echo 3u: ${x:+"glob_altvalue1.t*"}
+echo 4u: ${x:+glob_altvalue1.t\*}
+##echo 5u: ${x:+"glob_altvalue1.t\*"}
+
+echo 1q: "${x:+glob_altvalue1.t*}"
+echo 2q: "${x:+'glob_altvalue1.t*'}"
+echo 3q: "${x:+"glob_altvalue1.t*"}"
+##echo 4q: "${x:+glob_altvalue1.t\*}"
+##echo 5q: "${x:+"glob_altvalue1.t\*"}"

shell/hush.c

@@ -5994,7 +5994,19 @@ static int encode_then_append_var_plusminus(o_string *output, int n,
 			continue;
 		}
 #endif
-		o_addQchr(&dest, ch);
+		if (dquoted) {
+			/* Always glob-protect if in dquotes:
+			 * x=x; echo "${x:+/bin/c*}" - prints: /bin/c*
+			 * x=x; echo "${x:+"/bin/c*"}" - prints: /bin/c*
+			 */
+			o_addqchr(&dest, ch);
+		} else {
+			/* Glob-protect only if char is quoted:
+			 * x=x; echo ${x:+/bin/c*} - prints many filenames
+			 * x=x; echo ${x:+"/bin/c*"} - prints: /bin/c*
+			 */
+			o_addQchr(&dest, ch);
+		}
 	} /* for (;;) */
 
 	if (dest.data) {

shell/hush_test/hush-glob/glob_altvalue1.right

@@ -0,0 +1,7 @@
+1u: glob_altvalue1.tests
+2u: glob_altvalue1.t*
+3u: glob_altvalue1.t*
+4u: glob_altvalue1.t*
+1q: glob_altvalue1.t*
+2q: 'glob_altvalue1.t*'
+3q: glob_altvalue1.t*

shell/hush_test/hush-glob/glob_altvalue1.tests

@@ -0,0 +1,13 @@
+x=x
+
+echo 1u: ${x:+glob_altvalue1.t*}
+echo 2u: ${x:+'glob_altvalue1.t*'}
+echo 3u: ${x:+"glob_altvalue1.t*"}
+echo 4u: ${x:+glob_altvalue1.t\*}
+##echo 5u: ${x:+"glob_altvalue1.t\*"}
+
+echo 1q: "${x:+glob_altvalue1.t*}"
+echo 2q: "${x:+'glob_altvalue1.t*'}"
+echo 3q: "${x:+"glob_altvalue1.t*"}"
+##echo 4q: "${x:+glob_altvalue1.t\*}"
+##echo 5q: "${x:+"glob_altvalue1.t\*"}"