1  // Copyright (c) 2018-2022 The Bitcoin Core 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 <bitcoin-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  }