SERVER-14852 AAE safe read/write primitives

Alignment, aliasing and endian safe read write primitives in the form
of DataView and DataCursor primitives.  These primitives provide safe
reads and writes with explicit endian variants that funnel through
std::memcpy to provide defined behavior.

Support for a safe packed struct idiom is also provided in the
encoded_value_storage class.

1 files changed, 552 insertions, 0 deletions

diff --git a/src/mongo/platform/endian_test.cpp b/src/mongo/platform/endian_test.cpp
new file mode 100644
index 00000000000..733f9c69b0c
--- /dev/null
+++ b/src/mongo/platform/endian_test.cpp
@@ -0,0 +1,552 @@
+/*    Copyright 2014 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects
+ *    for all of the code used other than as permitted herein. If you modify
+ *    file(s) with this exception, you may extend this exception to your
+ *    version of the file(s), but you are not obligated to do so. If you do not
+ *    wish to do so, delete this exception statement from your version. If you
+ *    delete this exception statement from all source files in the program,
+ *    then also delete it in the license file.
+ */
+
+#include "mongo/platform/endian.h"
+
+#include <cstring>
+
+#include "mongo/unittest/unittest.h"
+
+namespace mongo {
+
+    TEST( EndianTest, TestSlow16 ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        uint16_t le;
+        uint16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+        ASSERT_EQUALS(be, endian::bswap_slow16(le));
+        ASSERT_EQUALS(le, endian::bswap_slow16(be));
+    }
+
+    TEST( EndianTest, TestSlow32 ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        uint32_t le;
+        uint32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+        ASSERT_EQUALS(be, endian::bswap_slow32(le));
+        ASSERT_EQUALS(le, endian::bswap_slow32(be));
+    }
+
+    TEST( EndianTest, TestSlow64 ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        uint64_t le;
+        uint64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+        ASSERT_EQUALS(be, endian::bswap_slow64(le));
+        ASSERT_EQUALS(le, endian::bswap_slow64(be));
+    }
+
+    TEST( EndianTest, NativeToBig_uint16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        uint16_t le;
+        uint16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_uint32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        uint32_t le;
+        uint32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_uint64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        uint64_t le;
+        uint64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_int16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        int16_t le;
+        int16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_int32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        int32_t le;
+        int32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_int64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        int64_t le;
+        int64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_float ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        float le;
+        float be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToBig_double ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        double le;
+        double be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(be, nativeToBig(le));
+#else
+        ASSERT_EQUALS(be, nativeToBig(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_uint16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        uint16_t le;
+        uint16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_uint32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        uint32_t le;
+        uint32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_uint64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        uint64_t le;
+        uint64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_int16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        int16_t le;
+        int16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_int32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        int32_t le;
+        int32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_int64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        int64_t le;
+        int64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_float ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        float le;
+        float be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, NativeToLittle_double ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        double le;
+        double be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, nativeToLittle(le));
+#else
+        ASSERT_EQUALS(le, nativeToLittle(be));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_uint16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        uint16_t le;
+        uint16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_uint32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        uint32_t le;
+        uint32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_uint64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        uint64_t le;
+        uint64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_int16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        int16_t le;
+        int16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_int32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        int32_t le;
+        int32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_int64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        int64_t le;
+        int64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_float ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        float le;
+        float be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, LittleToNative_double ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        double le;
+        double be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, littleToNative(le));
+#else
+        ASSERT_EQUALS(be, littleToNative(le));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_uint16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        uint16_t le;
+        uint16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_uint32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        uint32_t le;
+        uint32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_uint64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        uint64_t le;
+        uint64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_int16_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02 };
+        uint8_t be_buf[] = { 0x02, 0x01 };
+        int16_t le;
+        int16_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_int32_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        int32_t le;
+        int32_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_int64_t ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        int64_t le;
+        int64_t be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_float ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04 };
+        uint8_t be_buf[] = { 0x04, 0x03, 0x02, 0x01 };
+        float le;
+        float be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+    TEST( EndianTest, BigToNative_double ) {
+        uint8_t le_buf[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+        uint8_t be_buf[] = { 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01 };
+        double le;
+        double be;
+        std::memcpy(&le, le_buf, sizeof(le));
+        std::memcpy(&be, be_buf, sizeof(be));
+
+#if MONGO_BYTE_ORDER == 1234
+        ASSERT_EQUALS(le, bigToNative(be));
+#else
+        ASSERT_EQUALS(be, bigToNative(be));
+#endif
+    }
+
+} // namespace mongo