libcutils: Use strnlen for default property values
Add unit tests to test the corner cases.
Test: unit tests pass before and after the change.
Change-Id: Idafeb8354cd6c7db2a68cd398dafe153453a3940
diff --git a/libcutils/properties.c b/libcutils/properties.c
index 69c6c7f..740c7a9 100644
--- a/libcutils/properties.c
+++ b/libcutils/properties.c
@@ -119,10 +119,7 @@
return len;
}
if (default_value) {
- len = strlen(default_value);
- if (len >= PROPERTY_VALUE_MAX) {
- len = PROPERTY_VALUE_MAX - 1;
- }
+ len = strnlen(default_value, PROPERTY_VALUE_MAX - 1);
memcpy(value, default_value, len);
value[len] = '\0';
}
diff --git a/libcutils/tests/PropertiesTest.cpp b/libcutils/tests/PropertiesTest.cpp
index f0cdffd..7921972 100644
--- a/libcutils/tests/PropertiesTest.cpp
+++ b/libcutils/tests/PropertiesTest.cpp
@@ -159,19 +159,68 @@
TEST_F(PropertiesTest, GetString) {
- // Try to use a default value that's too long => set fails
+ // Try to use a default value that's too long => get truncates the value
{
ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
- std::string maxLengthString = std::string(PROPERTY_VALUE_MAX-1, 'a');
+ std::string maxLengthString = std::string(PROPERTY_VALUE_MAX - 1, 'a');
std::string oneLongerString = std::string(PROPERTY_VALUE_MAX, 'a');
// Expect that the value is truncated since it's too long (by 1)
int len = property_get(PROPERTY_TEST_KEY, mValue, oneLongerString.c_str());
- EXPECT_EQ(PROPERTY_VALUE_MAX-1, len);
+ EXPECT_EQ(PROPERTY_VALUE_MAX - 1, len);
EXPECT_STREQ(maxLengthString.c_str(), mValue);
ResetValue();
}
+
+ // Try to use a default value that's the max length => get succeeds
+ {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
+
+ std::string maxLengthString = std::string(PROPERTY_VALUE_MAX - 1, 'b');
+
+ // Expect that the value matches maxLengthString
+ int len = property_get(PROPERTY_TEST_KEY, mValue, maxLengthString.c_str());
+ EXPECT_EQ(PROPERTY_VALUE_MAX - 1, len);
+ EXPECT_STREQ(maxLengthString.c_str(), mValue);
+ ResetValue();
+ }
+
+ // Try to use a default value of length one => get succeeds
+ {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
+
+ std::string oneCharString = std::string(1, 'c');
+
+ // Expect that the value matches oneCharString
+ int len = property_get(PROPERTY_TEST_KEY, mValue, oneCharString.c_str());
+ EXPECT_EQ(1, len);
+ EXPECT_STREQ(oneCharString.c_str(), mValue);
+ ResetValue();
+ }
+
+ // Try to use a default value of length zero => get succeeds
+ {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
+
+ std::string zeroCharString = std::string(0, 'd');
+
+ // Expect that the value matches oneCharString
+ int len = property_get(PROPERTY_TEST_KEY, mValue, zeroCharString.c_str());
+ EXPECT_EQ(0, len);
+ EXPECT_STREQ(zeroCharString.c_str(), mValue);
+ ResetValue();
+ }
+
+ // Try to use a NULL default value => get returns 0
+ {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
+
+ // Expect a return value of 0
+ int len = property_get(PROPERTY_TEST_KEY, mValue, NULL);
+ EXPECT_EQ(0, len);
+ ResetValue();
+ }
}
TEST_F(PropertiesTest, GetBool) {