cutils: Add property_get_bool, _get_int32, _get_int64
* Read out system properties with same syntax as SystemProperties.java
* Also adds unit test suite to validate correctness of properties
* Also fixes buffer overrun in property_get
(cherry picked from commit d4507e9246e4855c5431cac5c3d1a9155caebc87)
Change-Id: Ifd42911f93e17da09e6ff1298e8875e02f3b6608
diff --git a/include/cutils/properties.h b/include/cutils/properties.h
index 2c70165..798db8b 100644
--- a/include/cutils/properties.h
+++ b/include/cutils/properties.h
@@ -20,6 +20,7 @@
#include <sys/cdefs.h>
#include <stddef.h>
#include <sys/system_properties.h>
+#include <stdint.h>
#ifdef __cplusplus
extern "C" {
@@ -44,6 +45,64 @@
*/
int property_get(const char *key, char *value, const char *default_value);
+/* property_get_bool: returns the value of key coerced into a
+** boolean. If the property is not set, then the default value is returned.
+**
+* The following is considered to be true (1):
+** "1", "true", "y", "yes", "on"
+**
+** The following is considered to be false (0):
+** "0", "false", "n", "no", "off"
+**
+** The conversion is whitespace-sensitive (e.g. " off" will not be false).
+**
+** If no property with this key is set (or the key is NULL) or the boolean
+** conversion fails, the default value is returned.
+**/
+int8_t property_get_bool(const char *key, int8_t default_value);
+
+/* property_get_int64: returns the value of key truncated and coerced into a
+** int64_t. If the property is not set, then the default value is used.
+**
+** The numeric conversion is identical to strtoimax with the base inferred:
+** - All digits up to the first non-digit characters are read
+** - The longest consecutive prefix of digits is converted to a long
+**
+** Valid strings of digits are:
+** - An optional sign character + or -
+** - An optional prefix indicating the base (otherwise base 10 is assumed)
+** -- 0 prefix is octal
+** -- 0x / 0X prefix is hex
+**
+** Leading/trailing whitespace is ignored. Overflow/underflow will cause
+** numeric conversion to fail.
+**
+** If no property with this key is set (or the key is NULL) or the numeric
+** conversion fails, the default value is returned.
+**/
+int64_t property_get_int64(const char *key, int64_t default_value);
+
+/* property_get_int32: returns the value of key truncated and coerced into an
+** int32_t. If the property is not set, then the default value is used.
+**
+** The numeric conversion is identical to strtoimax with the base inferred:
+** - All digits up to the first non-digit characters are read
+** - The longest consecutive prefix of digits is converted to a long
+**
+** Valid strings of digits are:
+** - An optional sign character + or -
+** - An optional prefix indicating the base (otherwise base 10 is assumed)
+** -- 0 prefix is octal
+** -- 0x / 0X prefix is hex
+**
+** Leading/trailing whitespace is ignored. Overflow/underflow will cause
+** numeric conversion to fail.
+**
+** If no property with this key is set (or the key is NULL) or the numeric
+** conversion fails, the default value is returned.
+**/
+int32_t property_get_int32(const char *key, int32_t default_value);
+
/* property_set: returns 0 on success, < 0 on failure
*/
int property_set(const char *key, const char *value);
diff --git a/libcutils/properties.c b/libcutils/properties.c
index 28d8b2f..bfbd1b8 100644
--- a/libcutils/properties.c
+++ b/libcutils/properties.c
@@ -15,17 +15,94 @@
*/
#define LOG_TAG "properties"
+// #define LOG_NDEBUG 0
#include <stdlib.h>
#include <string.h>
+#include <ctype.h>
#include <unistd.h>
#include <cutils/sockets.h>
#include <errno.h>
#include <assert.h>
#include <cutils/properties.h>
+#include <stdbool.h>
+#include <inttypes.h>
#include "loghack.h"
+int8_t property_get_bool(const char *key, int8_t default_value) {
+ if (!key) {
+ return default_value;
+ }
+
+ int8_t result = default_value;
+ char buf[PROPERTY_VALUE_MAX] = {'\0',};
+
+ int len = property_get(key, buf, "");
+ if (len == 1) {
+ char ch = buf[0];
+ if (ch == '0' || ch == 'n') {
+ result = false;
+ } else if (ch == '1' || ch == 'y') {
+ result = true;
+ }
+ } else if (len > 1) {
+ if (!strcmp(buf, "no") || !strcmp(buf, "false") || !strcmp(buf, "off")) {
+ result = false;
+ } else if (!strcmp(buf, "yes") || !strcmp(buf, "true") || !strcmp(buf, "on")) {
+ result = true;
+ }
+ }
+
+ return result;
+}
+
+// Convert string property to int (default if fails); return default value if out of bounds
+static intmax_t property_get_imax(const char *key, intmax_t lower_bound, intmax_t upper_bound,
+ intmax_t default_value) {
+ if (!key) {
+ return default_value;
+ }
+
+ intmax_t result = default_value;
+ char buf[PROPERTY_VALUE_MAX] = {'\0',};
+ char *end = NULL;
+
+ int len = property_get(key, buf, "");
+ if (len > 0) {
+ int tmp = errno;
+ errno = 0;
+
+ // Infer base automatically
+ result = strtoimax(buf, &end, /*base*/0);
+ if ((result == INTMAX_MIN || result == INTMAX_MAX) && errno == ERANGE) {
+ // Over or underflow
+ result = default_value;
+ ALOGV("%s(%s,%lld) - overflow", __FUNCTION__, key, default_value);
+ } else if (result < lower_bound || result > upper_bound) {
+ // Out of range of requested bounds
+ result = default_value;
+ ALOGV("%s(%s,%lld) - out of range", __FUNCTION__, key, default_value);
+ } else if (end == buf) {
+ // Numeric conversion failed
+ result = default_value;
+ ALOGV("%s(%s,%lld) - numeric conversion failed", __FUNCTION__, key, default_value);
+ }
+
+ errno = tmp;
+ }
+
+ return result;
+}
+
+int64_t property_get_int64(const char *key, int64_t default_value) {
+ return (int64_t)property_get_imax(key, INT64_MIN, INT64_MAX, default_value);
+}
+
+int32_t property_get_int32(const char *key, int32_t default_value) {
+ return (int32_t)property_get_imax(key, INT32_MIN, INT32_MAX, default_value);
+}
+
#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
@@ -44,10 +121,13 @@
if(len > 0) {
return len;
}
-
if(default_value) {
len = strlen(default_value);
- memcpy(value, default_value, len + 1);
+ if (len >= PROPERTY_VALUE_MAX) {
+ len = PROPERTY_VALUE_MAX - 1;
+ }
+ memcpy(value, default_value, len);
+ value[len] = '\0';
}
return len;
}
diff --git a/libcutils/tests/Android.mk b/libcutils/tests/Android.mk
new file mode 100644
index 0000000..e9d3ed7
--- /dev/null
+++ b/libcutils/tests/Android.mk
@@ -0,0 +1,31 @@
+# Copyright (C) 2014 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+test_src_files := \
+ PropertiesTest.cpp \
+
+shared_libraries := \
+ libutils
+
+static_libraries := \
+ libcutils
+
+LOCAL_SHARED_LIBRARIES := $(shared_libraries)
+LOCAL_STATIC_LIBRARIES := $(static_libraries)
+LOCAL_SRC_FILES := $(test_src_files)
+LOCAL_MODULE := libcutils_test
+include $(BUILD_NATIVE_TEST)
diff --git a/libcutils/tests/PropertiesTest.cpp b/libcutils/tests/PropertiesTest.cpp
new file mode 100644
index 0000000..659821c
--- /dev/null
+++ b/libcutils/tests/PropertiesTest.cpp
@@ -0,0 +1,309 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "Properties_test"
+#include <utils/Log.h>
+#include <gtest/gtest.h>
+
+#include <cutils/properties.h>
+#include <limits.h>
+#include <string>
+#include <sstream>
+#include <iostream>
+
+namespace android {
+
+#define STRINGIFY_INNER(x) #x
+#define STRINGIFY(x) STRINGIFY_INNER(x)
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof((x)[0]))
+#define ASSERT_OK(x) ASSERT_EQ(0, (x))
+#define EXPECT_OK(x) EXPECT_EQ(0, (x))
+
+#define PROPERTY_TEST_KEY "libcutils.test.key"
+#define PROPERTY_TEST_VALUE_DEFAULT "<<<default_value>>>"
+
+template <typename T>
+static std::string HexString(T value) {
+ std::stringstream ss;
+ ss << "0x" << std::hex << std::uppercase << value;
+ return ss.str();
+}
+
+template <typename T>
+static ::testing::AssertionResult AssertEqualHex(const char *mExpr,
+ const char *nExpr,
+ T m,
+ T n) {
+ if (m == n) {
+ return ::testing::AssertionSuccess();
+ }
+
+ return ::testing::AssertionFailure()
+ << mExpr << " and " << nExpr << " (expected: " << HexString(m) <<
+ ", actual: " << HexString(n) << ") are not equal";
+}
+
+class PropertiesTest : public testing::Test {
+public:
+ PropertiesTest() : mValue() {}
+protected:
+ virtual void SetUp() {
+ EXPECT_OK(property_set(PROPERTY_TEST_KEY, /*value*/NULL));
+ }
+
+ virtual void TearDown() {
+ EXPECT_OK(property_set(PROPERTY_TEST_KEY, /*value*/NULL));
+ }
+
+ char mValue[PROPERTY_VALUE_MAX];
+
+ template <typename T>
+ static std::string ToString(T value) {
+ std::stringstream ss;
+ ss << value;
+
+ return ss.str();
+ }
+
+ // Return length of property read; value is written into mValue
+ int SetAndGetProperty(const char* value, const char* defaultValue = PROPERTY_TEST_VALUE_DEFAULT) {
+ EXPECT_OK(property_set(PROPERTY_TEST_KEY, value)) << "value: '" << value << "'";
+ return property_get(PROPERTY_TEST_KEY, mValue, defaultValue);
+ }
+
+ void ResetValue(unsigned char c = 0xFF) {
+ for (size_t i = 0; i < ARRAY_SIZE(mValue); ++i) {
+ mValue[i] = (char) c;
+ }
+ }
+};
+
+TEST_F(PropertiesTest, SetString) {
+
+ // Null key -> unsuccessful set
+ {
+ // Null key -> fails
+ EXPECT_GT(0, property_set(/*key*/NULL, PROPERTY_TEST_VALUE_DEFAULT));
+ }
+
+ // Null value -> returns default value
+ {
+ // Null value -> OK , and it clears the value
+ EXPECT_OK(property_set(PROPERTY_TEST_KEY, /*value*/NULL));
+ ResetValue();
+
+ // Since the value is null, default value will be returned
+ int len = property_get(PROPERTY_TEST_KEY, mValue, PROPERTY_TEST_VALUE_DEFAULT);
+ EXPECT_EQ(strlen(PROPERTY_TEST_VALUE_DEFAULT), len);
+ EXPECT_STREQ(PROPERTY_TEST_VALUE_DEFAULT, mValue);
+ }
+
+ // Trivial case => get returns what was set
+ {
+ int len = SetAndGetProperty("hello_world");
+ EXPECT_EQ(strlen("hello_world"), len) << "hello_world key";
+ EXPECT_STREQ("hello_world", mValue);
+ ResetValue();
+ }
+
+ // Set to empty string => get returns default always
+ {
+ const char* EMPTY_STRING_DEFAULT = "EMPTY_STRING";
+ int len = SetAndGetProperty("", EMPTY_STRING_DEFAULT);
+ EXPECT_EQ(strlen(EMPTY_STRING_DEFAULT), len) << "empty key";
+ EXPECT_STREQ(EMPTY_STRING_DEFAULT, mValue);
+ ResetValue();
+ }
+
+ // Set to max length => get returns what was set
+ {
+ std::string maxLengthString = std::string(PROPERTY_VALUE_MAX-1, 'a');
+
+ int len = SetAndGetProperty(maxLengthString.c_str());
+ EXPECT_EQ(PROPERTY_VALUE_MAX-1, len) << "max length key";
+ EXPECT_STREQ(maxLengthString.c_str(), mValue);
+ ResetValue();
+ }
+
+ // Set to max length + 1 => set fails
+ {
+ const char* VALID_TEST_VALUE = "VALID_VALUE";
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, VALID_TEST_VALUE));
+
+ std::string oneLongerString = std::string(PROPERTY_VALUE_MAX, 'a');
+
+ // Expect that the value set fails since it's too long
+ EXPECT_GT(0, property_set(PROPERTY_TEST_KEY, oneLongerString.c_str()));
+ int len = property_get(PROPERTY_TEST_KEY, mValue, PROPERTY_TEST_VALUE_DEFAULT);
+
+ EXPECT_EQ(strlen(VALID_TEST_VALUE), len) << "set should've failed";
+ EXPECT_STREQ(VALID_TEST_VALUE, mValue);
+ ResetValue();
+ }
+}
+
+TEST_F(PropertiesTest, GetString) {
+
+ // Try to use a default value that's too long => set fails
+ {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, ""));
+
+ 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_STREQ(maxLengthString.c_str(), mValue);
+ ResetValue();
+ }
+}
+
+TEST_F(PropertiesTest, GetBool) {
+ /**
+ * TRUE
+ */
+ const char *valuesTrue[] = { "1", "true", "y", "yes", "on", };
+ for (size_t i = 0; i < ARRAY_SIZE(valuesTrue); ++i) {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, valuesTrue[i]));
+ bool val = property_get_bool(PROPERTY_TEST_KEY, /*default_value*/false);
+ EXPECT_TRUE(val) << "Property should've been TRUE for value: '" << valuesTrue[i] << "'";
+ }
+
+ /**
+ * FALSE
+ */
+ const char *valuesFalse[] = { "0", "false", "n", "no", "off", };
+ for (size_t i = 0; i < ARRAY_SIZE(valuesFalse); ++i) {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, valuesFalse[i]));
+ bool val = property_get_bool(PROPERTY_TEST_KEY, /*default_value*/true);
+ EXPECT_FALSE(val) << "Property shoud've been FALSE For string value: '" << valuesFalse[i] << "'";
+ }
+
+ /**
+ * NEITHER
+ */
+ const char *valuesNeither[] = { "x0", "x1", "2", "-2", "True", "False", "garbage", "", " ",
+ "+1", " 1 ", " true", " true ", " y ", " yes", "yes ",
+ "+0", "-0", "00", " 00 ", " false", "false ",
+ };
+ for (size_t i = 0; i < ARRAY_SIZE(valuesNeither); ++i) {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, valuesNeither[i]));
+
+ // The default value should always be used
+ bool val = property_get_bool(PROPERTY_TEST_KEY, /*default_value*/true);
+ EXPECT_TRUE(val) << "Property should've been NEITHER (true) for string value: '" << valuesNeither[i] << "'";
+
+ val = property_get_bool(PROPERTY_TEST_KEY, /*default_value*/false);
+ EXPECT_FALSE(val) << "Property should've been NEITHER (false) for string value: '" << valuesNeither[i] << "'";
+ }
+}
+
+TEST_F(PropertiesTest, GetInt64) {
+ const int64_t DEFAULT_VALUE = INT64_C(0xDEADBEEFBEEFDEAD);
+
+ const std::string longMaxString = ToString(INT64_MAX);
+ const std::string longStringOverflow = longMaxString + "0";
+
+ const std::string longMinString = ToString(INT64_MIN);
+ const std::string longStringUnderflow = longMinString + "0";
+
+ const char* setValues[] = {
+ // base 10
+ "1", "2", "12345", "-1", "-2", "-12345",
+ // base 16
+ "0xFF", "0x0FF", "0xC0FFEE",
+ // base 8
+ "0", "01234", "07",
+ // corner cases
+ " 2", "2 ", "+0", "-0", " +0 ", longMaxString.c_str(), longMinString.c_str(),
+ // failing cases
+ NULL, "", " ", " ", "hello", " true ", "y",
+ longStringOverflow.c_str(), longStringUnderflow.c_str(),
+ };
+
+ int64_t getValues[] = {
+ // base 10
+ 1, 2, 12345, -1, -2, -12345,
+ // base 16
+ 0xFF, 0x0FF, 0xC0FFEE,
+ // base 8
+ 0, 01234, 07,
+ // corner cases
+ 2, 2, 0, 0, 0, INT64_MAX, INT64_MIN,
+ // failing cases
+ DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE,
+ DEFAULT_VALUE, DEFAULT_VALUE,
+ };
+
+ ASSERT_EQ(ARRAY_SIZE(setValues), ARRAY_SIZE(getValues));
+
+ for (size_t i = 0; i < ARRAY_SIZE(setValues); ++i) {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, setValues[i]));
+
+ int64_t val = property_get_int64(PROPERTY_TEST_KEY, DEFAULT_VALUE);
+ EXPECT_PRED_FORMAT2(AssertEqualHex, getValues[i], val) << "Property was set to '" << setValues[i] << "'";
+ }
+}
+
+TEST_F(PropertiesTest, GetInt32) {
+ const int32_t DEFAULT_VALUE = INT32_C(0xDEADBEEF);
+
+ const std::string intMaxString = ToString(INT32_MAX);
+ const std::string intStringOverflow = intMaxString + "0";
+
+ const std::string intMinString = ToString(INT32_MIN);
+ const std::string intStringUnderflow = intMinString + "0";
+
+ const char* setValues[] = {
+ // base 10
+ "1", "2", "12345", "-1", "-2", "-12345",
+ // base 16
+ "0xFF", "0x0FF", "0xC0FFEE", "0Xf00",
+ // base 8
+ "0", "01234", "07",
+ // corner cases
+ " 2", "2 ", "+0", "-0", " +0 ", intMaxString.c_str(), intMinString.c_str(),
+ // failing cases
+ NULL, "", " ", " ", "hello", " true ", "y",
+ intStringOverflow.c_str(), intStringUnderflow.c_str(),
+ };
+
+ int32_t getValues[] = {
+ // base 10
+ 1, 2, 12345, -1, -2, -12345,
+ // base 16
+ 0xFF, 0x0FF, 0xC0FFEE, 0Xf00,
+ // base 8
+ 0, 01234, 07,
+ // corner cases
+ 2, 2, 0, 0, 0, INT32_MAX, INT32_MIN,
+ // failing cases
+ DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE, DEFAULT_VALUE,
+ DEFAULT_VALUE, DEFAULT_VALUE,
+ };
+
+ ASSERT_EQ(ARRAY_SIZE(setValues), ARRAY_SIZE(getValues));
+
+ for (size_t i = 0; i < ARRAY_SIZE(setValues); ++i) {
+ ASSERT_OK(property_set(PROPERTY_TEST_KEY, setValues[i]));
+
+ int32_t val = property_get_int32(PROPERTY_TEST_KEY, DEFAULT_VALUE);
+ EXPECT_PRED_FORMAT2(AssertEqualHex, getValues[i], val) << "Property was set to '" << setValues[i] << "'";
+ }
+}
+
+} // namespace android