1 //===-- ThreadLauncher.cpp ------------------------------------------------===//
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 // lldb Includes
10 #include "lldb/Host/ThreadLauncher.h"
11 #include "lldb/Host/HostNativeThread.h"
12 #include "lldb/Host/HostThread.h"
13 #include "lldb/Utility/Log.h"
14 
15 #if defined(_WIN32)
16 #include "lldb/Host/windows/windows.h"
17 #endif
18 
19 #include "llvm/Support/WindowsError.h"
20 
21 using namespace lldb;
22 using namespace lldb_private;
23 
24 llvm::Expected<HostThread> ThreadLauncher::LaunchThread(
25     llvm::StringRef name, lldb::thread_func_t thread_function,
26     lldb::thread_arg_t thread_arg, size_t min_stack_byte_size) {
27   // Host::ThreadCreateTrampoline will delete this pointer for us.
28   HostThreadCreateInfo *info_ptr =
29       new HostThreadCreateInfo(name.data(), thread_function, thread_arg);
30   lldb::thread_t thread;
31 #ifdef _WIN32
32   thread = (lldb::thread_t)::_beginthreadex(
33       0, (unsigned)min_stack_byte_size,
34       HostNativeThread::ThreadCreateTrampoline, info_ptr, 0, NULL);
35   if (thread == LLDB_INVALID_HOST_THREAD)
36     return llvm::errorCodeToError(llvm::mapWindowsError(GetLastError()));
37 #else
38 
39 // ASAN instrumentation adds a lot of bookkeeping overhead on stack frames.
40 #if __has_feature(address_sanitizer)
41   const size_t eight_megabytes = 8 * 1024 * 1024;
42   if (min_stack_byte_size < eight_megabytes) {
43     min_stack_byte_size += eight_megabytes;
44   }
45 #endif
46 
47   pthread_attr_t *thread_attr_ptr = nullptr;
48   pthread_attr_t thread_attr;
49   bool destroy_attr = false;
50   if (min_stack_byte_size > 0) {
51     if (::pthread_attr_init(&thread_attr) == 0) {
52       destroy_attr = true;
53       size_t default_min_stack_byte_size = 0;
54       if (::pthread_attr_getstacksize(&thread_attr,
55                                       &default_min_stack_byte_size) == 0) {
56         if (default_min_stack_byte_size < min_stack_byte_size) {
57           if (::pthread_attr_setstacksize(&thread_attr, min_stack_byte_size) ==
58               0)
59             thread_attr_ptr = &thread_attr;
60         }
61       }
62     }
63   }
64   int err =
65       ::pthread_create(&thread, thread_attr_ptr,
66                        HostNativeThread::ThreadCreateTrampoline, info_ptr);
67 
68   if (destroy_attr)
69     ::pthread_attr_destroy(&thread_attr);
70 
71   if (err)
72     return llvm::errorCodeToError(
73         std::error_code(err, std::generic_category()));
74 #endif
75 
76   return HostThread(thread);
77 }
78