xref: /aosp_15_r20/external/llvm-libc/test/src/sys/mman/linux/mremap_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for mremap ----------------------------------------------===//
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 "src/errno/libc_errno.h"
10 #include "src/sys/mman/mmap.h"
11 #include "src/sys/mman/mremap.h"
12 #include "src/sys/mman/munmap.h"
13 #include "test/UnitTest/ErrnoSetterMatcher.h"
14 #include "test/UnitTest/Test.h"
15 
16 #include <sys/mman.h>
17 
18 using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
19 using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
20 
TEST(LlvmLibcMremapTest,NoError)21 TEST(LlvmLibcMremapTest, NoError) {
22   size_t initial_size = 128;
23   size_t new_size = 256;
24   LIBC_NAMESPACE::libc_errno = 0;
25 
26   // Allocate memory using mmap.
27   void *addr =
28       LIBC_NAMESPACE::mmap(nullptr, initial_size, PROT_READ | PROT_WRITE,
29                            MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
30   ASSERT_ERRNO_SUCCESS();
31   EXPECT_NE(addr, MAP_FAILED);
32 
33   int *array = reinterpret_cast<int *>(addr);
34   // Writing to the memory should not crash the test.
35   array[0] = 123;
36   EXPECT_EQ(array[0], 123);
37 
38   // Re-map the memory using mremap with an increased size.
39   void *new_addr =
40       LIBC_NAMESPACE::mremap(addr, initial_size, new_size, MREMAP_MAYMOVE);
41   ASSERT_ERRNO_SUCCESS();
42   EXPECT_NE(new_addr, MAP_FAILED);
43   EXPECT_EQ(reinterpret_cast<int *>(new_addr)[0],
44             123); // Verify data is preserved.
45 
46   // Clean up memory by unmapping it.
47   EXPECT_THAT(LIBC_NAMESPACE::munmap(new_addr, new_size), Succeeds());
48 }
49 
TEST(LlvmLibcMremapTest,Error_InvalidSize)50 TEST(LlvmLibcMremapTest, Error_InvalidSize) {
51   size_t initial_size = 128;
52   LIBC_NAMESPACE::libc_errno = 0;
53 
54   // Allocate memory using mmap.
55   void *addr =
56       LIBC_NAMESPACE::mmap(nullptr, initial_size, PROT_READ | PROT_WRITE,
57                            MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
58   ASSERT_ERRNO_SUCCESS();
59   EXPECT_NE(addr, MAP_FAILED);
60 
61   // Attempt to re-map the memory with an invalid new size (0).
62   void *new_addr =
63       LIBC_NAMESPACE::mremap(addr, initial_size, 0, MREMAP_MAYMOVE);
64   EXPECT_THAT(new_addr, Fails(EINVAL, MAP_FAILED));
65 
66   // Clean up the original mapping.
67   EXPECT_THAT(LIBC_NAMESPACE::munmap(addr, initial_size), Succeeds());
68 }
69