threadnames.cpp raw
1 // Copyright (c) 2018-2022 The Limenka developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5 #include <limenka-build-config.h> // IWYU pragma: keep
6
7 #include <cstring>
8 #include <string>
9 #include <thread>
10 #include <utility>
11
12 #if (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
13 #include <pthread.h>
14 #include <pthread_np.h>
15 #endif
16
17 #include <util/threadnames.h>
18
19 #ifdef HAVE_SYS_PRCTL_H
20 #include <sys/prctl.h>
21 #endif
22
23 //! Set the thread's name at the process level. Does not affect the
24 //! internal name.
25 static void SetThreadName(const char* name)
26 {
27 #if defined(PR_SET_NAME)
28 // Only the first 15 characters are used (16 - NUL terminator)
29 ::prctl(PR_SET_NAME, name, 0, 0, 0);
30 #elif (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
31 pthread_set_name_np(pthread_self(), name);
32 #elif defined(__APPLE__)
33 pthread_setname_np(name);
34 #else
35 // Prevent warnings for unused parameters...
36 (void)name;
37 #endif
38 }
39
40 /**
41 * The name of the thread. We use char array instead of std::string to avoid
42 * complications with running a destructor when the thread exits. Avoid adding
43 * other thread_local variables.
44 * @see https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=278701
45 */
46 static thread_local char g_thread_name[128]{'\0'};
47 std::string util::ThreadGetInternalName() { return g_thread_name; }
48 //! Set the in-memory internal name for this thread. Does not affect the process
49 //! name.
50 static void SetInternalName(const std::string& name)
51 {
52 const size_t copy_bytes{std::min(sizeof(g_thread_name) - 1, name.length())};
53 std::memcpy(g_thread_name, name.data(), copy_bytes);
54 g_thread_name[copy_bytes] = '\0';
55 }
56
57 void util::ThreadRename(const std::string& name)
58 {
59 SetThreadName(("b-" + name).c_str());
60 SetInternalName(name);
61 }
62
63 void util::ThreadSetInternalName(const std::string& name)
64 {
65 SetInternalName(name);
66 }
67