Let's make sure people invoking STRV_FOREACH_BACKWARDS() as a single statement
of an if statement don't fall into a trap, and find the tail for the list via
strv_length().
#define STRV_FOREACH(s, l) \
for ((s) = (l); (s) && *(s); (s)++)
-#define STRV_FOREACH_BACKWARDS(s, l) \
- STRV_FOREACH(s, l) \
- ; \
- for ((s)--; (l) && ((s) >= (l)); (s)--)
+#define STRV_FOREACH_BACKWARDS(s, l) \
+ for (s = ({ \
+ char **_l = l; \
+ _l ? _l + strv_length(_l) - 1U : NULL; \
+ }); \
+ (l) && ((s) >= (l)); \
+ (s)--)
#define STRV_FOREACH_PAIR(x, y, l) \
for ((x) = (l), (y) = (x+1); (x) && *(x) && *(y); (x) += 2, (y) = (x + 1))
assert_se(a);
- STRV_FOREACH_BACKWARDS(check, a) {
+ STRV_FOREACH_BACKWARDS(check, a)
assert_se(streq_ptr(*check, input_table_multiple[i--]));
- }
+
+ STRV_FOREACH_BACKWARDS(check, (char**) NULL)
+ assert_not_reached("Let's see that we check empty strv right, too.");
+
+ STRV_FOREACH_BACKWARDS(check, (char**) { NULL })
+ assert_not_reached("Let's see that we check empty strv right, too.");
}
static void test_strv_foreach_pair(void) {