Flesh out <sys/msg.h>, <sys/sem.h>, <sys/shm.h>.

Also fix <sys/ipc.h>.

Not useful except to systems/bringup folks for testing. Trivial tests
added, and double-checked under strace to see that things look right.

x86 -- which works differently to everything else -- tested on the host.

Bug: http://b/27952303
Change-Id: I328534e994ae9e90755f545478fba03038c0bb94
diff --git a/tests/sys_msg_test.cpp b/tests/sys_msg_test.cpp
new file mode 100644
index 0000000..e715979
--- /dev/null
+++ b/tests/sys_msg_test.cpp
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <gtest/gtest.h>
+
+#include <errno.h>
+#include <sys/msg.h>
+
+#include "TemporaryFile.h"
+
+TEST(sys_msg, smoke) {
+  // Create a queue.
+  TemporaryDir dir;
+  key_t key = ftok(dir.dirname, 1);
+  int id = msgget(key, IPC_CREAT|0666);
+  ASSERT_NE(id, -1);
+
+  // Queue should be empty.
+  msqid_ds ds;
+  memset(&ds, 0, sizeof(ds));
+  ASSERT_EQ(0, msgctl(id, IPC_STAT, &ds));
+  ASSERT_EQ(0U, ds.msg_qnum);
+  ASSERT_EQ(0U, ds.msg_cbytes);
+
+  // Send a message.
+  struct {
+    long type;
+    char data[32];
+  } msg = { 1, "hello world" };
+  ASSERT_EQ(0, msgsnd(id, &msg, sizeof(msg), 0));
+
+  // Queue should be non-empty.
+  ASSERT_EQ(0, msgctl(id, IPC_STAT, &ds));
+  ASSERT_EQ(1U, ds.msg_qnum);
+  ASSERT_EQ(sizeof(msg), ds.msg_cbytes);
+
+  // Read the message.
+  memset(&msg, 0, sizeof(msg));
+  ASSERT_EQ(static_cast<ssize_t>(sizeof(msg)), msgrcv(id, &msg, sizeof(msg), 0, 0));
+  ASSERT_EQ(1, msg.type);
+  ASSERT_STREQ("hello world", msg.data);
+
+  // Destroy the queue.
+  ASSERT_EQ(0, msgctl(id, IPC_RMID, 0));
+}
+
+TEST(sys_msg, msgctl_failure) {
+  errno = 0;
+  ASSERT_EQ(-1, msgctl(-1, IPC_STAT, nullptr));
+  ASSERT_EQ(EINVAL, errno);
+}
+
+TEST(sys_msg, msgget_failure) {
+  errno = 0;
+  ASSERT_EQ(-1, msgget(-1, 0));
+  ASSERT_EQ(ENOENT, errno);
+}
+
+TEST(sys_msg, msgrcv_failure) {
+  errno = 0;
+  ASSERT_EQ(-1, msgrcv(-1, nullptr, 0, 0, 0));
+  ASSERT_EQ(EINVAL, errno);
+}
+
+TEST(sys_msg, msgsnd_failure) {
+  errno = 0;
+  ASSERT_EQ(-1, msgsnd(-1, "", 0, 0));
+  ASSERT_EQ(EINVAL, errno);
+}