Fix dev_t (for LP64).

32-bit Android's dev_t was wrong too. We can't fix that without ABI breakage,
but we can at least fix 64-bit Android. And add tests.

Bug: https://code.google.com/p/android/issues/detail?id=54966
Change-Id: Ie2e42cc042b78b669a1a44e55f959dbd9c52c5c9

libc/include/sys/_types.h

@@ -37,7 +37,6 @@
 #include <machine/_types.h>
 
 typedef	unsigned long	__cpuid_t;	/* CPU id */
-typedef	__int32_t	__dev_t;	/* device number */
 typedef	__uint32_t	__fixpt_t;	/* fixed point number */
 typedef	__uint32_t	__gid_t;	/* group id */
 typedef	__uint32_t	__id_t;		/* may contain pid, uid or gid */

libc/include/sys/types.h

@@ -47,10 +47,8 @@ typedef __kernel_caddr_t caddr_t;
 typedef __kernel_clock_t clock_t;
 typedef __kernel_clockid_t clockid_t;
 typedef __kernel_daddr_t daddr_t;
-typedef uint32_t dev_t;
 typedef unsigned long fsblkcnt_t;
 typedef unsigned long fsfilcnt_t;
-typedef uint32_t id_t;
 typedef __kernel_ino_t ino_t;
 typedef __kernel_key_t key_t;
 typedef __kernel_mode_t mode_t;
@@ -60,6 +58,13 @@ typedef __kernel_suseconds_t suseconds_t;
 typedef __kernel_timer_t timer_t;
 typedef unsigned int useconds_t;
 
+#if !defined(__LP64__)
+/* This historical accident means that we had a 32-bit dev_t on 32-bit architectures. */
+typedef uint32_t dev_t;
+#else
+typedef uint64_t dev_t;
+#endif
+
 /* This historical accident means that we had a 32-bit time_t on 32-bit architectures. */
 typedef __kernel_time_t time_t;
 
@@ -71,6 +76,9 @@ typedef __kernel_off_t off_t;
 typedef __kernel_loff_t loff_t;
 typedef loff_t off64_t;
 
+/* This one really is meant to be just 32 bits! */
+typedef uint32_t id_t;
+
 /* while POSIX wants these in <sys/types.h>, we
  * declare then in <pthread.h> instead */
 #if 0

tests/Android.mk

@@ -66,6 +66,7 @@ test_src_files = \
     sys_stat_test.cpp \
     sys_syscall_test.cpp \
     sys_time_test.cpp \
+    sys_types_test.cpp \
     system_properties_test.cpp \
     time_test.cpp \
     unistd_test.cpp \

tests/sys_types_test.cpp

@@ -0,0 +1,43 @@
+/*
+ * 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.
+ */
+
+#include <gtest/gtest.h>
+
+#include <sys/types.h>
+
+TEST(sys_types, type_sizes) {
+  // gids, pids, and uids should be 32-bit on all systems.
+  ASSERT_EQ(4U, sizeof(gid_t));
+  ASSERT_EQ(4U, sizeof(pid_t));
+  ASSERT_EQ(4U, sizeof(uid_t));
+  // id_t is the 'generic'.
+  ASSERT_EQ(4U, sizeof(id_t));
+
+  // Some types were too small on 32-bit Android by mistake,
+  // but are correct on 64-bit Android.
+#if defined(__LP64__)
+  ASSERT_EQ(8U, sizeof(dev_t));
+  ASSERT_EQ(8U, sizeof(off_t));
+  ASSERT_EQ(8U, sizeof(time_t));
+#else
+  ASSERT_EQ(4U, sizeof(dev_t));
+  ASSERT_EQ(4U, sizeof(off_t));
+  ASSERT_EQ(4U, sizeof(time_t));
+#endif
+  // These were right even on 32-bit Android.
+  ASSERT_EQ(8U, sizeof(loff_t));
+  ASSERT_EQ(8U, sizeof(off64_t));
+}