selftests/bpf: Support glob matching for test selector.

This patch adds '-a' and '-d' arguments supporting both exact string match as
well as using '*' wildcard in test/subtests selection. '-a' and '-t' can
co-exists, same as '-d' and '-b', in which case they just add to the list of
allowed or denied test selectors.

Caveat: Same as the current substring matching mechanism, test and subtest
selector applies independently, 'a*/b*' will execute all tests matching "a*",
and with subtest name matching "b*", but tests matching "a*" that has no
subtests will also be executed.

Signed-off-by: Yucong Sun <[e-mail]>
Signed-off-by: Andrii Nakryiko <[e-mail]>
Link: https://lore.kernel.org/bpf/[e-mail]

tools/testing/selftests/bpf/test_progs.c

···
 #include <execinfo.h> /* backtrace */
 #include <linux/membarrier.h>
 
+/* Adapted from perf/util/string.c */
+static bool glob_match(const char *str, const char *pat)
+{
+	while (*str && *pat && *pat != '*') {
+		if (*str != *pat)
+			return false;
+		str++;
+		pat++;
+	}
+	/* Check wild card */
+	if (*pat == '*') {
+		while (*pat == '*')
+			pat++;
+		if (!*pat) /* Tail wild card matches all */
+			return true;
+		while (*str)
+			if (glob_match(str++, pat))
+				return true;
+	}
+	return !*str && !*pat;
+}
+
 #define EXIT_NO_TEST		2
 #define EXIT_ERR_SETUP_INFRA	3
 
···
 	int i;
 
 	for (i = 0; i < sel->blacklist.cnt; i++) {
-		if (strstr(name, sel->blacklist.strs[i]))
+		if (glob_match(name, sel->blacklist.strs[i]))
 			return false;
 	}
 
 	for (i = 0; i < sel->whitelist.cnt; i++) {
-		if (strstr(name, sel->whitelist.strs[i]))
+		if (glob_match(name, sel->whitelist.strs[i]))
 			return true;
 	}
 
···
 	ARG_VERBOSE = 'v',
 	ARG_GET_TEST_CNT = 'c',
 	ARG_LIST_TEST_NAMES = 'l',
+	ARG_TEST_NAME_GLOB_ALLOWLIST = 'a',
+	ARG_TEST_NAME_GLOB_DENYLIST = 'd',
 };
 
 static const struct argp_option opts[] = {
···
 	  "Get number of selected top-level tests " },
 	{ "list", ARG_LIST_TEST_NAMES, NULL, 0,
 	  "List test names that would run (without running them) " },
+	{ "allow", ARG_TEST_NAME_GLOB_ALLOWLIST, "NAMES", 0,
+	  "Run tests with name matching the pattern (supports '*' wildcard)." },
+	{ "deny", ARG_TEST_NAME_GLOB_DENYLIST, "NAMES", 0,
+	  "Don't run tests with name matching the pattern (supports '*' wildcard)." },
 	{},
 };
 
···
 	free(set->strs);
 }
 
-static int parse_str_list(const char *s, struct str_set *set)
+static int parse_str_list(const char *s, struct str_set *set, bool is_glob_pattern)
 {
 	char *input, *state = NULL, *next, **tmp, **strs = NULL;
-	int cnt = 0;
+	int i, cnt = 0;
 
 	input = strdup(s);
 	if (!input)
 		return -ENOMEM;
-
-	set->cnt = 0;
-	set->strs = NULL;
 
 	while ((next = strtok_r(state ? NULL : input, ",", &state))) {
 		tmp = realloc(strs, sizeof(*strs) * (cnt + 1));
···
 			goto err;
 		strs = tmp;
 
-		strs[cnt] = strdup(next);
-		if (!strs[cnt])
-			goto err;
+		if (is_glob_pattern) {
+			strs[cnt] = strdup(next);
+			if (!strs[cnt])
+				goto err;
+		} else {
+			strs[cnt] = malloc(strlen(next) + 2 + 1);
+			if (!strs[cnt])
+				goto err;
+			sprintf(strs[cnt], "*%s*", next);
+		}
 
 		cnt++;
 	}
 
-	set->cnt = cnt;
-	set->strs = (const char **)strs;
+	tmp = realloc(set->strs, sizeof(*strs) * (cnt + set->cnt));
+	if (!tmp)
+		goto err;
+	memcpy(tmp + set->cnt, strs, sizeof(*strs) * cnt);
+	set->strs = (const char **)tmp;
+	set->cnt += cnt;
+
 	free(input);
+	free(strs);
 	return 0;
 err:
+	for (i = 0; i < cnt; i++)
+		free(strs[i]);
 	free(strs);
 	free(input);
 	return -ENOMEM;
···
 		}
 		break;
 	}
+	case ARG_TEST_NAME_GLOB_ALLOWLIST:
 	case ARG_TEST_NAME: {
 		char *subtest_str = strchr(arg, '/');
 
 		if (subtest_str) {
 			*subtest_str = '\0';
 			if (parse_str_list(subtest_str + 1,
-					   &env->subtest_selector.whitelist))
+					   &env->subtest_selector.whitelist,
+					   key == ARG_TEST_NAME_GLOB_ALLOWLIST))
 				return -ENOMEM;
 		}
-		if (parse_str_list(arg, &env->test_selector.whitelist))
+		if (parse_str_list(arg, &env->test_selector.whitelist,
+				   key == ARG_TEST_NAME_GLOB_ALLOWLIST))
 			return -ENOMEM;
 		break;
 	}
+	case ARG_TEST_NAME_GLOB_DENYLIST:
 	case ARG_TEST_NAME_BLACKLIST: {
 		char *subtest_str = strchr(arg, '/');
 
 		if (subtest_str) {
 			*subtest_str = '\0';
 			if (parse_str_list(subtest_str + 1,
-					   &env->subtest_selector.blacklist))
+					   &env->subtest_selector.blacklist,
+					   key == ARG_TEST_NAME_GLOB_DENYLIST))
 				return -ENOMEM;
 		}
-		if (parse_str_list(arg, &env->test_selector.blacklist))
+		if (parse_str_list(arg, &env->test_selector.blacklist,
+				   key == ARG_TEST_NAME_GLOB_DENYLIST))
 			return -ENOMEM;
 		break;
 	}