Netflix was using this, and looking the header file, although
__system_property_find_nth has been available since the beginning of time,
__system_property_foreach only appeared in 16. So anyone who wants to run
on pre-JellyBean devices would want to use __system_property_find_nth.
It's pretty much a one-liner in terms of __system_property_foreach anyway,
so it doesn't cost us anything to keep it.
Also restore slightly better tests than we originally removed.
Bug: http://b/
36566667
Test: ran tests
(cherry picked from commit
438e01940b90a2b6061a9b9809e08466e1e9faac)
Change-Id: I639f2142ad4ba049b990b13ccccd255be4b4f479
DISALLOW_IMPLICIT_CONSTRUCTORS(prop_info);
};
-struct find_nth_cookie {
- uint32_t count;
- const uint32_t n;
- const prop_info* pi;
-
- explicit find_nth_cookie(uint32_t n) : count(0), n(n), pi(nullptr) {
- }
-};
-
// This is public because it was exposed in the NDK. As of 2017-01, ~60 apps reference this symbol.
prop_area* __system_property_area__ = nullptr;
return result;
}
-static void find_nth_fn(const prop_info* pi, void* ptr) {
- find_nth_cookie* cookie = reinterpret_cast<find_nth_cookie*>(ptr);
-
- if (cookie->n == cookie->count) cookie->pi = pi;
-
- cookie->count++;
-}
-
bool prop_area::foreach_property(prop_bt* const trie,
void (*propfn)(const prop_info* pi, void* cookie), void* cookie) {
if (!trie) return false;
}
const prop_info* __system_property_find_nth(unsigned n) {
- if (bionic_get_application_target_sdk_version() >= __ANDROID_API_O__) {
- __libc_fatal(
- "__system_property_find_nth is not supported since Android O,"
- " please use __system_property_foreach instead.");
- }
-
- find_nth_cookie cookie(n);
-
- const int err = __system_property_foreach(find_nth_fn, &cookie);
- if (err < 0) {
- return nullptr;
- }
-
- return cookie.pi;
+ struct find_nth {
+ const uint32_t sought;
+ uint32_t current;
+ const prop_info* result;
+
+ explicit find_nth(uint32_t n) : sought(n), current(0), result(nullptr) {}
+ static void fn(const prop_info* pi, void* ptr) {
+ find_nth* self = reinterpret_cast<find_nth*>(ptr);
+ if (self->current++ == self->sought) self->result = pi;
+ }
+ } state(n);
+ __system_property_foreach(find_nth::fn, &state);
+ return state.result;
}
int __system_property_foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie) {
list_foreach(contexts, [propfn, cookie](context_node* l) {
if (l->check_access_and_open()) {
- l->pa()->foreach (propfn, cookie);
+ l->pa()->foreach(propfn, cookie);
}
});
return 0;
/* Deprecated. In Android O and above, there's no limit on property name length. */
#define PROP_NAME_MAX 32
/* Deprecated. Use __system_property_read_callback instead. */
-int __system_property_read(const prop_info *pi, char *name, char *value);
+int __system_property_read(const prop_info* pi, char* name, char* value);
/* Deprecated. Use __system_property_read_callback instead. */
-int __system_property_get(const char *name, char *value);
-/* Deprecated. Use __system_property_foreach instead. Aborts in Android O and above. */
-const prop_info *__system_property_find_nth(unsigned n) __REMOVED_IN(26);
+int __system_property_get(const char* name, char* value);
+/* Deprecated. Use __system_property_foreach instead. */
+const prop_info* __system_property_find_nth(unsigned n);
__END_DECLS
ASSERT_EQ(0, __system_property_add("other_property", 14, "value2", 6));
ASSERT_EQ(0, __system_property_add("property_other", 14, "value3", 6));
- // This method is no longer supported and should result in abort
- ASSERT_EXIT(__system_property_find_nth(0), testing::KilledBySignal(SIGABRT),
- "__system_property_find_nth is not supported since Android O,"
- " please use __system_property_foreach instead.");
+ char name[PROP_NAME_MAX];
+ char value[PROP_VALUE_MAX];
+ EXPECT_EQ(6, __system_property_read(__system_property_find_nth(0), name, value));
+ EXPECT_STREQ("property", name);
+ EXPECT_STREQ("value1", value);
+ EXPECT_EQ(6, __system_property_read(__system_property_find_nth(1), name, value));
+ EXPECT_STREQ("other_property", name);
+ EXPECT_STREQ("value2", value);
+ EXPECT_EQ(6, __system_property_read(__system_property_find_nth(2), name, value));
+ EXPECT_STREQ("property_other", name);
+ EXPECT_STREQ("value3", value);
+
+ for (unsigned i = 3; i < 1024; ++i) {
+ ASSERT_TRUE(__system_property_find_nth(i) == nullptr);
+ }
#else // __BIONIC__
GTEST_LOG_(INFO) << "This test does nothing.\n";
#endif // __BIONIC__