ladybird/AK/StackInfo.cpp
Andrew Kaster 1d533acbc0 AK+Userland: Replace Linux, macOS, and *BSD macros with platform defines
We have such nice platform macros, let's clean up any remnants of manual
__my_platform__ macros in LibCore, LibCompress and AK.
2022-10-10 12:23:12 +02:00

78 lines
2.3 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Assertions.h>
#include <AK/Platform.h>
#include <AK/StackInfo.h>
#include <stdio.h>
#include <string.h>
#ifdef AK_OS_SERENITY
# include <serenity.h>
#elif defined(AK_OS_LINUX) or defined(AK_OS_MACOS)
# include <pthread.h>
#elif defined(AK_OS_FREEBSD)
# include <pthread.h>
# include <pthread_np.h>
#endif
namespace AK {
StackInfo::StackInfo()
{
#ifdef AK_OS_SERENITY
if (get_stack_bounds(&m_base, &m_size) < 0) {
perror("get_stack_bounds");
VERIFY_NOT_REACHED();
}
#elif defined(AK_OS_LINUX) or defined(AK_OS_FREEBSD)
int rc;
pthread_attr_t attr;
pthread_attr_init(&attr);
# ifdef AK_OS_LINUX
if ((rc = pthread_getattr_np(pthread_self(), &attr)) != 0) {
fprintf(stderr, "pthread_getattr_np: %s\n", strerror(rc));
VERIFY_NOT_REACHED();
}
# else
if ((rc = pthread_attr_get_np(pthread_self(), &attr)) != 0) {
fprintf(stderr, "pthread_attr_get_np: %s\n", strerror(rc));
VERIFY_NOT_REACHED();
}
# endif
if ((rc = pthread_attr_getstack(&attr, (void**)&m_base, &m_size)) != 0) {
fprintf(stderr, "pthread_attr_getstack: %s\n", strerror(rc));
VERIFY_NOT_REACHED();
}
pthread_attr_destroy(&attr);
#elif defined(AK_OS_MACOS)
// NOTE: !! On MacOS, pthread_get_stackaddr_np gives the TOP of the stack, not the bottom!
FlatPtr top_of_stack = (FlatPtr)pthread_get_stackaddr_np(pthread_self());
m_size = (size_t)pthread_get_stacksize_np(pthread_self());
// https://github.com/rust-lang/rust/issues/43347#issuecomment-316783599
// https://developer.apple.com/library/archive/qa/qa1419/_index.html
//
// MacOS seems inconsistent on what stack size is given for the main thread.
// According to the Apple docs, default for main thread is 8MB, and default for
// other threads is 512KB
constexpr size_t eight_megabytes = 0x800000;
if (pthread_main_np() == 1 && m_size < eight_megabytes) {
// Assume no one messed with stack size linker options for the main thread,
// and just set it to 8MB.
m_size = eight_megabytes;
}
m_base = top_of_stack - m_size;
#else
VERIFY_NOT_REACHED();
#endif
m_top = m_base + m_size;
}
}