jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2020, the SerenityOS developers.
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/Assertions.h>
8#include <AK/Platform.h>
9#include <AK/StackInfo.h>
10#include <stdio.h>
11#include <string.h>
12
13#ifdef AK_OS_SERENITY
14# include <serenity.h>
15#elif defined(AK_OS_LINUX) or defined(AK_OS_MACOS) or defined(AK_OS_NETBSD) or defined(AK_OS_SOLARIS)
16# include <pthread.h>
17#elif defined(AK_OS_FREEBSD) or defined(AK_OS_OPENBSD)
18# include <pthread.h>
19# include <pthread_np.h>
20#elif defined(AK_OS_WINDOWS)
21# include <Windows.h>
22// NOTE: Prevent clang-format from re-ordering this header order
23# include <Processthreadsapi.h>
24#endif
25
26namespace AK {
27
28StackInfo::StackInfo()
29{
30#ifdef AK_OS_SERENITY
31 if (get_stack_bounds(&m_base, &m_size) < 0) {
32 perror("get_stack_bounds");
33 VERIFY_NOT_REACHED();
34 }
35#elif defined(AK_OS_LINUX) or defined(AK_OS_FREEBSD) or defined(AK_OS_NETBSD) or defined(AK_OS_SOLARIS)
36 int rc;
37 pthread_attr_t attr;
38 pthread_attr_init(&attr);
39
40# ifdef AK_OS_LINUX
41 if ((rc = pthread_getattr_np(pthread_self(), &attr)) != 0) {
42 fprintf(stderr, "pthread_getattr_np: %s\n", strerror(rc));
43 VERIFY_NOT_REACHED();
44 }
45# else
46 if ((rc = pthread_attr_get_np(pthread_self(), &attr)) != 0) {
47 fprintf(stderr, "pthread_attr_get_np: %s\n", strerror(rc));
48 VERIFY_NOT_REACHED();
49 }
50# endif
51
52 if ((rc = pthread_attr_getstack(&attr, (void**)&m_base, &m_size)) != 0) {
53 fprintf(stderr, "pthread_attr_getstack: %s\n", strerror(rc));
54 VERIFY_NOT_REACHED();
55 }
56 pthread_attr_destroy(&attr);
57#elif defined(AK_OS_MACOS)
58 // NOTE: !! On MacOS, pthread_get_stackaddr_np gives the TOP of the stack, not the bottom!
59 FlatPtr top_of_stack = (FlatPtr)pthread_get_stackaddr_np(pthread_self());
60 m_size = (size_t)pthread_get_stacksize_np(pthread_self());
61 // https://github.com/rust-lang/rust/issues/43347#issuecomment-316783599
62 // https://developer.apple.com/library/archive/qa/qa1419/_index.html
63 //
64 // MacOS seems inconsistent on what stack size is given for the main thread.
65 // According to the Apple docs, default for main thread is 8MB, and default for
66 // other threads is 512KB
67 constexpr size_t eight_megabytes = 0x800000;
68 if (pthread_main_np() == 1 && m_size < eight_megabytes) {
69 // Assume no one messed with stack size linker options for the main thread,
70 // and just set it to 8MB.
71 m_size = eight_megabytes;
72 }
73 m_base = top_of_stack - m_size;
74#elif defined(AK_OS_OPENBSD)
75 int rc;
76 stack_t thread_stack;
77 if ((rc = pthread_stackseg_np(pthread_self(), &thread_stack)) != 0) {
78 fprintf(stderr, "pthread_stackseg_np: %s\n", strerror(rc));
79 VERIFY_NOT_REACHED();
80 }
81 FlatPtr top_of_stack = (FlatPtr)thread_stack.ss_sp;
82 m_size = (size_t)thread_stack.ss_size;
83 m_base = top_of_stack - m_size;
84#elif defined(AK_OS_WINDOWS)
85 ULONG_PTR low_limit = 0;
86 ULONG_PTR high_limit = 0;
87 GetCurrentThreadStackLimits(&low_limit, &high_limit);
88
89 m_base = static_cast<FlatPtr>(low_limit);
90 m_size = static_cast<size_t>(high_limit - low_limit);
91#else
92# pragma message "StackInfo not supported on this platform! Recursion checks and stack scans may not work properly"
93 m_size = (size_t)~0;
94 m_base = 0;
95#endif
96
97 m_top = m_base + m_size;
98}
99
100}