xref: /aosp_15_r20/external/llvm-libc/test/src/sys/mman/linux/shm_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for shm_open/shm_unlink ---------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "hdr/fcntl_macros.h"
10 #include "src/__support/OSUtil/syscall.h"
11 #include "src/fcntl/fcntl.h"
12 #include "src/sys/mman/mmap.h"
13 #include "src/sys/mman/munmap.h"
14 #include "src/sys/mman/shm_open.h"
15 #include "src/sys/mman/shm_unlink.h"
16 #include "src/unistd/close.h"
17 #include "src/unistd/ftruncate.h"
18 #include "test/UnitTest/ErrnoSetterMatcher.h"
19 #include "test/UnitTest/Test.h"
20 #include <sys/syscall.h>
21 
22 using namespace LIBC_NAMESPACE::testing::ErrnoSetterMatcher;
23 // since shm_open/shm_unlink are wrappers around open/unlink, we only focus on
24 // testing basic cases and name conversions.
25 
TEST(LlvmLibcShmTest,Basic)26 TEST(LlvmLibcShmTest, Basic) {
27   const char *name = "/test_shm_open";
28   int fd;
29   ASSERT_THAT(fd = LIBC_NAMESPACE::shm_open(name, O_CREAT | O_RDWR, 0666),
30               returns(GE(0)).with_errno(EQ(0)));
31 
32   // check that FD_CLOEXEC is set by default.
33   long flag = LIBC_NAMESPACE::fcntl(fd, F_GETFD);
34   ASSERT_GE(static_cast<int>(flag), 0);
35   EXPECT_NE(static_cast<int>(flag) & FD_CLOEXEC, 0);
36 
37   // allocate space using ftruncate
38   ASSERT_THAT(LIBC_NAMESPACE::ftruncate(fd, 4096), Succeeds());
39   // map the shared memory
40   void *addr = LIBC_NAMESPACE::mmap(nullptr, 4096, PROT_READ | PROT_WRITE,
41                                     MAP_SHARED, fd, 0);
42   ASSERT_NE(addr, MAP_FAILED);
43   // just write random data to the shared memory
44   char data[] = "Despite its name, LLVM has little to do with traditional "
45                 "virtual machines.";
46   for (size_t i = 0; i < sizeof(data); ++i)
47     static_cast<char *>(addr)[i] = data[i];
48 
49   // close fd does not affect the mapping
50   ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds());
51   for (size_t i = 0; i < sizeof(data); ++i)
52     EXPECT_EQ(static_cast<char *>(addr)[i], data[i]);
53 
54   // unmap the shared memory
55   ASSERT_THAT(LIBC_NAMESPACE::munmap(addr, 4096), Succeeds());
56   // remove the shared memory
57   ASSERT_THAT(LIBC_NAMESPACE::shm_unlink(name), Succeeds());
58 }
59 
TEST(LlvmLibcShmTest,NameConversion)60 TEST(LlvmLibcShmTest, NameConversion) {
61   const char *name = "////test_shm_open";
62   int fd;
63   ASSERT_THAT(fd = LIBC_NAMESPACE::shm_open(name, O_CREAT | O_RDWR, 0666),
64               returns(GE(0)).with_errno(EQ(0)));
65   ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds());
66   ASSERT_THAT(LIBC_NAMESPACE::shm_unlink(name), Succeeds());
67 
68   ASSERT_THAT(LIBC_NAMESPACE::shm_open("/123/123", O_CREAT | O_RDWR, 0666),
69               Fails(EINVAL));
70 
71   ASSERT_THAT(LIBC_NAMESPACE::shm_open("/.", O_CREAT | O_RDWR, 0666),
72               Fails(EINVAL));
73 
74   ASSERT_THAT(LIBC_NAMESPACE::shm_open("/..", O_CREAT | O_RDWR, 0666),
75               Fails(EINVAL));
76 }
77