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/libc/bionic/sys_shm.cpp b/libc/bionic/sys_shm.cpp
new file mode 100644
index 0000000..6f1b8f5
--- /dev/null
+++ b/libc/bionic/sys_shm.cpp
@@ -0,0 +1,73 @@
+/*
+ * 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 <sys/shm.h>
+
+#include <sys/syscall.h>
+#include <unistd.h>
+
+void* shmat(int id, const void* address, int flags) {
+#if __i386__
+ // See the kernel's ipc/syscall.c for the other side of this dance.
+ void* result = nullptr;
+ if (syscall(SYS_ipc, SHMAT, id, flags, &result, address, 0) == -1) {
+ return reinterpret_cast<void*>(-1);
+ }
+ return result;
+#else
+ return reinterpret_cast<void*>(syscall(SYS_shmat, id, address, flags));
+#endif
+}
+
+int shmctl(int id, int cmd, struct shmid_ds* buf) {
+#if !defined(__LP64__)
+ // Annoyingly, the kernel requires this for 32-bit but rejects it for 64-bit.
+ cmd |= IPC_64;
+#endif
+#if __i386__
+ return syscall(SYS_ipc, SHMCTL, id, cmd, 0, buf, 0);
+#else
+ return syscall(SYS_shmctl, id, cmd, buf);
+#endif
+}
+
+int shmdt(const void* address) {
+#if __i386__
+ return syscall(SYS_ipc, SHMDT, 0, 0, 0, address, 0);
+#else
+ return syscall(SYS_shmdt, address);
+#endif
+}
+
+int shmget(key_t key, size_t size, int flags) {
+#if __i386__
+ return syscall(SYS_ipc, SHMGET, key, size, flags, 0, 0);
+#else
+ return syscall(SYS_shmget, key, size, flags);
+#endif
+}