summaryrefslogtreecommitdiff
path: root/Python/thread.c
blob: f90cd34a073540a6f72b3ce3b723048d34184af6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199

/* Thread package.
   This is intended to be usable independently from Python.
   The implementation for system foobar is in a file thread_foobar.h
   which is included by this file dependent on config settings.
   Stuff shared by all thread_*.h files is collected here. */

#include "Python.h"
#include "pycore_pystate.h"       // _PyInterpreterState_GET()
#include "pycore_structseq.h"     // _PyStructSequence_FiniBuiltin()
#include "pycore_pythread.h"

#ifndef DONT_HAVE_STDIO_H
#include <stdio.h>
#endif

#include <stdlib.h>


static void PyThread__init_thread(void); /* Forward */

#define initialized _PyRuntime.threads.initialized

void
PyThread_init_thread(void)
{
    if (initialized) {
        return;
    }
    initialized = 1;
    PyThread__init_thread();
}

#if defined(HAVE_PTHREAD_STUBS)
#   define PYTHREAD_NAME "pthread-stubs"
#   include "thread_pthread_stubs.h"
#elif defined(_USE_PTHREADS)  /* AKA _PTHREADS */
#   if defined(__EMSCRIPTEN__) && !defined(__EMSCRIPTEN_PTHREADS__)
#     define PYTHREAD_NAME "pthread-stubs"
#   else
#     define PYTHREAD_NAME "pthread"
#   endif
#   include "thread_pthread.h"
#elif defined(NT_THREADS)
#   define PYTHREAD_NAME "nt"
#   include "thread_nt.h"
#else
#   error "Require native threads. See https://bugs.python.org/issue31370"
#endif


/* return the current thread stack size */
size_t
PyThread_get_stacksize(void)
{
    return _PyInterpreterState_GET()->threads.stacksize;
}

/* Only platforms defining a THREAD_SET_STACKSIZE() macro
   in thread_<platform>.h support changing the stack size.
   Return 0 if stack size is valid,
      -1 if stack size value is invalid,
      -2 if setting stack size is not supported. */
int
PyThread_set_stacksize(size_t size)
{
#if defined(THREAD_SET_STACKSIZE)
    return THREAD_SET_STACKSIZE(size);
#else
    return -2;
#endif
}


/* Thread Specific Storage (TSS) API

   Cross-platform components of TSS API implementation.
*/

Py_tss_t *
PyThread_tss_alloc(void)
{
    Py_tss_t *new_key = (Py_tss_t *)PyMem_RawMalloc(sizeof(Py_tss_t));
    if (new_key == NULL) {
        return NULL;
    }
    new_key->_is_initialized = 0;
    return new_key;
}

void
PyThread_tss_free(Py_tss_t *key)
{
    if (key != NULL) {
        PyThread_tss_delete(key);
        PyMem_RawFree((void *)key);
    }
}

int
PyThread_tss_is_created(Py_tss_t *key)
{
    assert(key != NULL);
    return key->_is_initialized;
}


PyDoc_STRVAR(threadinfo__doc__,
"sys.thread_info\n\
\n\
A named tuple holding information about the thread implementation.");

static PyStructSequence_Field threadinfo_fields[] = {
    {"name",    "name of the thread implementation"},
    {"lock",    "name of the lock implementation"},
    {"version", "name and version of the thread library"},
    {0}
};

static PyStructSequence_Desc threadinfo_desc = {
    "sys.thread_info",           /* name */
    threadinfo__doc__,           /* doc */
    threadinfo_fields,           /* fields */
    3
};

static PyTypeObject ThreadInfoType;

PyObject*
PyThread_GetInfo(void)
{
    PyObject *threadinfo, *value;
    int pos = 0;
#if (defined(_POSIX_THREADS) && defined(HAVE_CONFSTR) \
     && defined(_CS_GNU_LIBPTHREAD_VERSION))
    char buffer[255];
    int len;
#endif

    if (_PyStructSequence_InitBuiltin(&ThreadInfoType, &threadinfo_desc) < 0) {
        return NULL;
    }

    threadinfo = PyStructSequence_New(&ThreadInfoType);
    if (threadinfo == NULL)
        return NULL;

    value = PyUnicode_FromString(PYTHREAD_NAME);
    if (value == NULL) {
        Py_DECREF(threadinfo);
        return NULL;
    }
    PyStructSequence_SET_ITEM(threadinfo, pos++, value);

#ifdef HAVE_PTHREAD_STUBS
    value = Py_NewRef(Py_None);
#elif defined(_POSIX_THREADS)
#ifdef USE_SEMAPHORES
    value = PyUnicode_FromString("semaphore");
#else
    value = PyUnicode_FromString("mutex+cond");
#endif
    if (value == NULL) {
        Py_DECREF(threadinfo);
        return NULL;
    }
#else
    value = Py_NewRef(Py_None);
#endif
    PyStructSequence_SET_ITEM(threadinfo, pos++, value);

#if (defined(_POSIX_THREADS) && defined(HAVE_CONFSTR) \
     && defined(_CS_GNU_LIBPTHREAD_VERSION))
    value = NULL;
    len = confstr(_CS_GNU_LIBPTHREAD_VERSION, buffer, sizeof(buffer));
    if (1 < len && (size_t)len < sizeof(buffer)) {
        value = PyUnicode_DecodeFSDefaultAndSize(buffer, len-1);
        if (value == NULL)
            PyErr_Clear();
    }
    if (value == NULL)
#endif
    {
        value = Py_NewRef(Py_None);
    }
    PyStructSequence_SET_ITEM(threadinfo, pos++, value);
    return threadinfo;
}


void
_PyThread_FiniType(PyInterpreterState *interp)
{
    if (!_Py_IsMainInterpreter(interp)) {
        return;
    }

    _PyStructSequence_FiniBuiltin(&ThreadInfoType);
}