From 67b18a18b66b89e253f38895057ef9f6bae92e7b Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Fri, 6 Dec 2024 17:27:12 +0100 Subject: gh-59705: Add _thread.set_name() function (#127338) On Linux, threading.Thread now sets the thread name to the operating system. * configure now checks if pthread_getname_np() and pthread_setname_np() functions are available. * Add PYTHREAD_NAME_MAXLEN macro. * Add _thread._NAME_MAXLEN constant for test_threading. Co-authored-by: Serhiy Storchaka --- Lib/test/test_threading.py | 60 ++++++++++++ Lib/threading.py | 9 ++ .../2024-11-27-17-04-38.gh-issue-59705.sAGyvs.rst | 2 + Modules/_threadmodule.c | 108 +++++++++++++++++++++ Modules/clinic/_threadmodule.c.h | 104 ++++++++++++++++++++ configure | 30 ++++++ configure.ac | 22 ++++- pyconfig.h.in | 9 ++ 8 files changed, 342 insertions(+), 2 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2024-11-27-17-04-38.gh-issue-59705.sAGyvs.rst create mode 100644 Modules/clinic/_threadmodule.c.h diff --git a/Lib/test/test_threading.py b/Lib/test/test_threading.py index fe22555..d05161f 100644 --- a/Lib/test/test_threading.py +++ b/Lib/test/test_threading.py @@ -2104,6 +2104,66 @@ class MiscTestCase(unittest.TestCase): support.check__all__(self, threading, ('threading', '_thread'), extra=extra, not_exported=not_exported) + @unittest.skipUnless(hasattr(_thread, 'set_name'), "missing _thread.set_name") + @unittest.skipUnless(hasattr(_thread, '_get_name'), "missing _thread._get_name") + def test_set_name(self): + # set_name() limit in bytes + truncate = getattr(_thread, "_NAME_MAXLEN", None) + limit = truncate or 100 + + tests = [ + # test short ASCII name + "CustomName", + + # test short non-ASCII name + "namé€", + + # embedded null character: name is truncated + # at the first null character + "embed\0null", + + # Test long ASCII names (not truncated) + "x" * limit, + + # Test long ASCII names (truncated) + "x" * (limit + 10), + + # Test long non-ASCII name (truncated) + "x" * (limit - 1) + "é€", + ] + if os_helper.FS_NONASCII: + tests.append(f"nonascii:{os_helper.FS_NONASCII}") + if os_helper.TESTFN_UNENCODABLE: + tests.append(os_helper.TESTFN_UNENCODABLE) + + if sys.platform.startswith("solaris"): + encoding = "utf-8" + else: + encoding = sys.getfilesystemencoding() + + def work(): + nonlocal work_name + work_name = _thread._get_name() + + for name in tests: + encoded = name.encode(encoding, "replace") + if b'\0' in encoded: + encoded = encoded.split(b'\0', 1)[0] + if truncate is not None: + encoded = encoded[:truncate] + if sys.platform.startswith("solaris"): + expected = encoded.decode("utf-8", "surrogateescape") + else: + expected = os.fsdecode(encoded) + + with self.subTest(name=name, expected=expected): + work_name = None + thread = threading.Thread(target=work, name=name) + thread.start() + thread.join() + self.assertEqual(work_name, expected, + f"{len(work_name)=} and {len(expected)=}") + class InterruptMainTests(unittest.TestCase): def check_interrupt_main_with_signal_handler(self, signum): diff --git a/Lib/threading.py b/Lib/threading.py index 94ea2f0..3abd22a 100644 --- a/Lib/threading.py +++ b/Lib/threading.py @@ -48,6 +48,10 @@ try: __all__.append('get_native_id') except AttributeError: _HAVE_THREAD_NATIVE_ID = False +try: + _set_name = _thread.set_name +except AttributeError: + _set_name = None ThreadError = _thread.error try: _CRLock = _thread.RLock @@ -1027,6 +1031,11 @@ class Thread: self._set_ident() if _HAVE_THREAD_NATIVE_ID: self._set_native_id() + if _set_name is not None and self._name: + try: + _set_name(self._name) + except OSError: + pass self._started.set() with _active_limbo_lock: _active[self._ident] = self diff --git a/Misc/NEWS.d/next/Library/2024-11-27-17-04-38.gh-issue-59705.sAGyvs.rst b/Misc/NEWS.d/next/Library/2024-11-27-17-04-38.gh-issue-59705.sAGyvs.rst new file mode 100644 index 0000000..a8c7b3d --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-11-27-17-04-38.gh-issue-59705.sAGyvs.rst @@ -0,0 +1,2 @@ +On Linux, :class:`threading.Thread` now sets the thread name to the +operating system. Patch by Victor Stinner. diff --git a/Modules/_threadmodule.c b/Modules/_threadmodule.c index 4a45445..35c032f 100644 --- a/Modules/_threadmodule.c +++ b/Modules/_threadmodule.c @@ -17,6 +17,8 @@ # include // SIGINT #endif +#include "clinic/_threadmodule.c.h" + // ThreadError is just an alias to PyExc_RuntimeError #define ThreadError PyExc_RuntimeError @@ -44,6 +46,13 @@ get_thread_state(PyObject *module) return (thread_module_state *)state; } + +/*[clinic input] +module _thread +[clinic start generated code]*/ +/*[clinic end generated code: output=da39a3ee5e6b4b0d input=be8dbe5cc4b16df7]*/ + + // _ThreadHandle type // Handles state transitions according to the following diagram: @@ -2354,6 +2363,96 @@ PyDoc_STRVAR(thread__get_main_thread_ident_doc, Internal only. Return a non-zero integer that uniquely identifies the main thread\n\ of the main interpreter."); + +#ifdef HAVE_PTHREAD_GETNAME_NP +/*[clinic input] +_thread._get_name + +Get the name of the current thread. +[clinic start generated code]*/ + +static PyObject * +_thread__get_name_impl(PyObject *module) +/*[clinic end generated code: output=20026e7ee3da3dd7 input=35cec676833d04c8]*/ +{ + // Linux and macOS are limited to respectively 16 and 64 bytes + char name[100]; + pthread_t thread = pthread_self(); + int rc = pthread_getname_np(thread, name, Py_ARRAY_LENGTH(name)); + if (rc) { + errno = rc; + return PyErr_SetFromErrno(PyExc_OSError); + } + +#ifdef __sun + return PyUnicode_DecodeUTF8(name, strlen(name), "surrogateescape"); +#else + return PyUnicode_DecodeFSDefault(name); +#endif +} +#endif // HAVE_PTHREAD_GETNAME_NP + + +#ifdef HAVE_PTHREAD_SETNAME_NP +/*[clinic input] +_thread.set_name + + name as name_obj: unicode + +Set the name of the current thread. +[clinic start generated code]*/ + +static PyObject * +_thread_set_name_impl(PyObject *module, PyObject *name_obj) +/*[clinic end generated code: output=402b0c68e0c0daed input=7e7acd98261be82f]*/ +{ +#ifdef __sun + // Solaris always uses UTF-8 + const char *encoding = "utf-8"; +#else + // Encode the thread name to the filesystem encoding using the "replace" + // error handler + PyInterpreterState *interp = _PyInterpreterState_GET(); + const char *encoding = interp->unicode.fs_codec.encoding; +#endif + PyObject *name_encoded; + name_encoded = PyUnicode_AsEncodedString(name_obj, encoding, "replace"); + if (name_encoded == NULL) { + return NULL; + } + +#ifdef PYTHREAD_NAME_MAXLEN + // Truncate to PYTHREAD_NAME_MAXLEN bytes + the NUL byte if needed + size_t len = PyBytes_GET_SIZE(name_encoded); + if (len > PYTHREAD_NAME_MAXLEN) { + PyObject *truncated; + truncated = PyBytes_FromStringAndSize(PyBytes_AS_STRING(name_encoded), + PYTHREAD_NAME_MAXLEN); + if (truncated == NULL) { + Py_DECREF(name_encoded); + return NULL; + } + Py_SETREF(name_encoded, truncated); + } +#endif + + const char *name = PyBytes_AS_STRING(name_encoded); +#ifdef __APPLE__ + int rc = pthread_setname_np(name); +#else + pthread_t thread = pthread_self(); + int rc = pthread_setname_np(thread, name); +#endif + Py_DECREF(name_encoded); + if (rc) { + errno = rc; + return PyErr_SetFromErrno(PyExc_OSError); + } + Py_RETURN_NONE; +} +#endif // HAVE_PTHREAD_SETNAME_NP + + static PyMethodDef thread_methods[] = { {"start_new_thread", (PyCFunction)thread_PyThread_start_new_thread, METH_VARARGS, start_new_thread_doc}, @@ -2393,6 +2492,8 @@ static PyMethodDef thread_methods[] = { METH_O, thread__make_thread_handle_doc}, {"_get_main_thread_ident", thread__get_main_thread_ident, METH_NOARGS, thread__get_main_thread_ident_doc}, + _THREAD_SET_NAME_METHODDEF + _THREAD__GET_NAME_METHODDEF {NULL, NULL} /* sentinel */ }; @@ -2484,6 +2585,13 @@ thread_module_exec(PyObject *module) llist_init(&state->shutdown_handles); +#ifdef PYTHREAD_NAME_MAXLEN + if (PyModule_AddIntConstant(module, "_NAME_MAXLEN", + PYTHREAD_NAME_MAXLEN) < 0) { + return -1; + } +#endif + return 0; } diff --git a/Modules/clinic/_threadmodule.c.h b/Modules/clinic/_threadmodule.c.h new file mode 100644 index 0000000..8f0507d --- /dev/null +++ b/Modules/clinic/_threadmodule.c.h @@ -0,0 +1,104 @@ +/*[clinic input] +preserve +[clinic start generated code]*/ + +#if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE) +# include "pycore_gc.h" // PyGC_Head +# include "pycore_runtime.h" // _Py_ID() +#endif +#include "pycore_modsupport.h" // _PyArg_UnpackKeywords() + +#if defined(HAVE_PTHREAD_GETNAME_NP) + +PyDoc_STRVAR(_thread__get_name__doc__, +"_get_name($module, /)\n" +"--\n" +"\n" +"Get the name of the current thread."); + +#define _THREAD__GET_NAME_METHODDEF \ + {"_get_name", (PyCFunction)_thread__get_name, METH_NOARGS, _thread__get_name__doc__}, + +static PyObject * +_thread__get_name_impl(PyObject *module); + +static PyObject * +_thread__get_name(PyObject *module, PyObject *Py_UNUSED(ignored)) +{ + return _thread__get_name_impl(module); +} + +#endif /* defined(HAVE_PTHREAD_GETNAME_NP) */ + +#if defined(HAVE_PTHREAD_SETNAME_NP) + +PyDoc_STRVAR(_thread_set_name__doc__, +"set_name($module, /, name)\n" +"--\n" +"\n" +"Set the name of the current thread."); + +#define _THREAD_SET_NAME_METHODDEF \ + {"set_name", _PyCFunction_CAST(_thread_set_name), METH_FASTCALL|METH_KEYWORDS, _thread_set_name__doc__}, + +static PyObject * +_thread_set_name_impl(PyObject *module, PyObject *name_obj); + +static PyObject * +_thread_set_name(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames) +{ + PyObject *return_value = NULL; + #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE) + + #define NUM_KEYWORDS 1 + static struct { + PyGC_Head _this_is_not_used; + PyObject_VAR_HEAD + PyObject *ob_item[NUM_KEYWORDS]; + } _kwtuple = { + .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS) + .ob_item = { &_Py_ID(name), }, + }; + #undef NUM_KEYWORDS + #define KWTUPLE (&_kwtuple.ob_base.ob_base) + + #else // !Py_BUILD_CORE + # define KWTUPLE NULL + #endif // !Py_BUILD_CORE + + static const char * const _keywords[] = {"name", NULL}; + static _PyArg_Parser _parser = { + .keywords = _keywords, + .fname = "set_name", + .kwtuple = KWTUPLE, + }; + #undef KWTUPLE + PyObject *argsbuf[1]; + PyObject *name_obj; + + args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, + /*minpos*/ 1, /*maxpos*/ 1, /*minkw*/ 0, /*varpos*/ 0, argsbuf); + if (!args) { + goto exit; + } + if (!PyUnicode_Check(args[0])) { + _PyArg_BadArgument("set_name", "argument 'name'", "str", args[0]); + goto exit; + } + name_obj = args[0]; + return_value = _thread_set_name_impl(module, name_obj); + +exit: + return return_value; +} + +#endif /* defined(HAVE_PTHREAD_SETNAME_NP) */ + +#ifndef _THREAD__GET_NAME_METHODDEF + #define _THREAD__GET_NAME_METHODDEF +#endif /* !defined(_THREAD__GET_NAME_METHODDEF) */ + +#ifndef _THREAD_SET_NAME_METHODDEF + #define _THREAD_SET_NAME_METHODDEF +#endif /* !defined(_THREAD_SET_NAME_METHODDEF) */ +/*[clinic end generated code: output=b5cb85aaccc45bf6 input=a9049054013a1b77]*/ diff --git a/configure b/configure index 5e9bcb6..bcbab8d 100755 --- a/configure +++ b/configure @@ -821,6 +821,7 @@ MODULE_TIME_TRUE MODULE__IO_FALSE MODULE__IO_TRUE MODULE_BUILDTYPE +PYTHREAD_NAME_MAXLEN TEST_MODULES OPENSSL_LDFLAGS OPENSSL_LIBS @@ -18842,6 +18843,18 @@ then : printf "%s\n" "#define HAVE_PTHREAD_KILL 1" >>confdefs.h fi +ac_fn_c_check_func "$LINENO" "pthread_getname_np" "ac_cv_func_pthread_getname_np" +if test "x$ac_cv_func_pthread_getname_np" = xyes +then : + printf "%s\n" "#define HAVE_PTHREAD_GETNAME_NP 1" >>confdefs.h + +fi +ac_fn_c_check_func "$LINENO" "pthread_setname_np" "ac_cv_func_pthread_setname_np" +if test "x$ac_cv_func_pthread_setname_np" = xyes +then : + printf "%s\n" "#define HAVE_PTHREAD_SETNAME_NP 1" >>confdefs.h + +fi ac_fn_c_check_func "$LINENO" "ptsname" "ac_cv_func_ptsname" if test "x$ac_cv_func_ptsname" = xyes then : @@ -29081,6 +29094,23 @@ fi CPPFLAGS=$save_CPPFLAGS +# gh-59705: Maximum length in bytes of a thread name +case "$ac_sys_system" in + Linux*) PYTHREAD_NAME_MAXLEN=15;; # Linux and Android + SunOS*) PYTHREAD_NAME_MAXLEN=31;; + Darwin) PYTHREAD_NAME_MAXLEN=63;; + iOS) PYTHREAD_NAME_MAXLEN=63;; + FreeBSD*) PYTHREAD_NAME_MAXLEN=98;; + *) PYTHREAD_NAME_MAXLEN=;; +esac +if test -n "$PYTHREAD_NAME_MAXLEN"; then + +printf "%s\n" "#define PYTHREAD_NAME_MAXLEN $PYTHREAD_NAME_MAXLEN" >>confdefs.h + +fi + + + # stdlib diff --git a/configure.ac b/configure.ac index bf3685e..922a125 100644 --- a/configure.ac +++ b/configure.ac @@ -5110,8 +5110,10 @@ AC_CHECK_FUNCS([ \ mknod mknodat mktime mmap mremap nice openat opendir pathconf pause pipe \ pipe2 plock poll posix_fadvise posix_fallocate posix_openpt posix_spawn posix_spawnp \ posix_spawn_file_actions_addclosefrom_np \ - pread preadv preadv2 process_vm_readv pthread_cond_timedwait_relative_np pthread_condattr_setclock pthread_init \ - pthread_kill ptsname ptsname_r pwrite pwritev pwritev2 readlink readlinkat readv realpath renameat \ + pread preadv preadv2 process_vm_readv \ + pthread_cond_timedwait_relative_np pthread_condattr_setclock pthread_init \ + pthread_kill pthread_getname_np pthread_setname_np \ + ptsname ptsname_r pwrite pwritev pwritev2 readlink readlinkat readv realpath renameat \ rtpSpawn sched_get_priority_max sched_rr_get_interval sched_setaffinity \ sched_setparam sched_setscheduler sem_clockwait sem_getvalue sem_open \ sem_timedwait sem_unlink sendfile setegid seteuid setgid sethostname \ @@ -7498,6 +7500,22 @@ AS_VAR_IF([ac_cv_libatomic_needed], [yes], _RESTORE_VAR([CPPFLAGS]) +# gh-59705: Maximum length in bytes of a thread name +case "$ac_sys_system" in + Linux*) PYTHREAD_NAME_MAXLEN=15;; # Linux and Android + SunOS*) PYTHREAD_NAME_MAXLEN=31;; + Darwin) PYTHREAD_NAME_MAXLEN=63;; + iOS) PYTHREAD_NAME_MAXLEN=63;; + FreeBSD*) PYTHREAD_NAME_MAXLEN=98;; + *) PYTHREAD_NAME_MAXLEN=;; +esac +if test -n "$PYTHREAD_NAME_MAXLEN"; then + AC_DEFINE_UNQUOTED([PYTHREAD_NAME_MAXLEN], [$PYTHREAD_NAME_MAXLEN], + [Maximum length in bytes of a thread name]) +fi +AC_SUBST([PYTHREAD_NAME_MAXLEN]) + + # stdlib AC_DEFUN([PY_STDLIB_MOD_SET_NA], [ m4_foreach([mod], [$@], [ diff --git a/pyconfig.h.in b/pyconfig.h.in index 6a1f128..166c195 100644 --- a/pyconfig.h.in +++ b/pyconfig.h.in @@ -981,6 +981,9 @@ /* Define to 1 if you have the `pthread_getcpuclockid' function. */ #undef HAVE_PTHREAD_GETCPUCLOCKID +/* Define to 1 if you have the `pthread_getname_np' function. */ +#undef HAVE_PTHREAD_GETNAME_NP + /* Define to 1 if you have the header file. */ #undef HAVE_PTHREAD_H @@ -990,6 +993,9 @@ /* Define to 1 if you have the `pthread_kill' function. */ #undef HAVE_PTHREAD_KILL +/* Define to 1 if you have the `pthread_setname_np' function. */ +#undef HAVE_PTHREAD_SETNAME_NP + /* Define to 1 if you have the `pthread_sigmask' function. */ #undef HAVE_PTHREAD_SIGMASK @@ -1650,6 +1656,9 @@ /* Define as the preferred size in bits of long digits */ #undef PYLONG_BITS_IN_DIGIT +/* Maximum length in bytes of a thread name */ +#undef PYTHREAD_NAME_MAXLEN + /* enabled builtin hash modules */ #undef PY_BUILTIN_HASHLIB_HASHES -- cgit v0.12