1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/shm.h>
30
31 #include <sys/syscall.h>
32 #include <unistd.h>
33
shmat(int id,const void * address,int flags)34 void* shmat(int id, const void* address, int flags) {
35 #if defined(SYS_shmat)
36 return reinterpret_cast<void*>(syscall(SYS_shmat, id, address, flags));
37 #else
38 // See the kernel's ipc/syscall.c for the other side of this dance.
39 void* result = nullptr;
40 if (syscall(SYS_ipc, SHMAT, id, flags, &result, address, 0) == -1) {
41 return reinterpret_cast<void*>(-1);
42 }
43 return result;
44 #endif
45 }
46
shmctl(int id,int cmd,struct shmid_ds * buf)47 int shmctl(int id, int cmd, struct shmid_ds* buf) {
48 #if !defined(__LP64__) || defined(__mips__)
49 // Annoyingly, the kernel requires this for 32-bit but rejects it for 64-bit.
50 // Mips64 is an exception to this, it requires the flag.
51 cmd |= IPC_64;
52 #endif
53 #if defined(SYS_shmctl)
54 return syscall(SYS_shmctl, id, cmd, buf);
55 #else
56 return syscall(SYS_ipc, SHMCTL, id, cmd, 0, buf, 0);
57 #endif
58 }
59
shmdt(const void * address)60 int shmdt(const void* address) {
61 #if defined(SYS_shmdt)
62 return syscall(SYS_shmdt, address);
63 #else
64 return syscall(SYS_ipc, SHMDT, 0, 0, 0, address, 0);
65 #endif
66 }
67
shmget(key_t key,size_t size,int flags)68 int shmget(key_t key, size_t size, int flags) {
69 #if defined(SYS_shmget)
70 return syscall(SYS_shmget, key, size, flags);
71 #else
72 return syscall(SYS_ipc, SHMGET, key, size, flags, 0, 0);
73 #endif
74 }
75