2 * python-plugin-provider.c
4 * Babeltrace Python plugin provider
6 * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
27 #define BT_LOG_TAG "PLUGIN-PY"
29 #include <babeltrace/babeltrace-internal.h>
30 #include <babeltrace/compiler-internal.h>
31 #include <babeltrace/plugin/plugin-const.h>
32 #include <babeltrace/plugin/plugin-internal.h>
33 #include <babeltrace/graph/component-class.h>
34 #include <babeltrace/graph/component-class-internal.h>
41 #define PYTHON_PLUGIN_FILE_PREFIX "bt_plugin_"
42 #define PYTHON_PLUGIN_FILE_PREFIX_LEN (sizeof(PYTHON_PLUGIN_FILE_PREFIX) - 1)
43 #define PYTHON_PLUGIN_FILE_EXT ".py"
44 #define PYTHON_PLUGIN_FILE_EXT_LEN (sizeof(PYTHON_PLUGIN_FILE_EXT) - 1)
47 /* init_python() not called yet */
48 PYTHON_STATE_NOT_INITED
,
50 /* init_python() called once with success */
51 PYTHON_STATE_FULLY_INITIALIZED
,
53 /* init_python() called once without success */
54 PYTHON_STATE_CANNOT_INITIALIZE
,
55 } python_state
= PYTHON_STATE_NOT_INITED
;
57 static PyObject
*py_try_load_plugin_module_func
= NULL
;
58 static bool python_was_initialized_by_us
;
61 void print_python_traceback_warn(void)
63 if (BT_LOG_ON_WARN
&& Py_IsInitialized() && PyErr_Occurred()) {
64 BT_LOGW_STR("Exception occured: traceback: ");
70 void pyerr_clear(void)
72 if (Py_IsInitialized()) {
78 void init_python(void)
80 PyObject
*py_bt2_py_plugin_mod
= NULL
;
81 const char *dis_python_env
;
83 sighandler_t old_sigint
= signal(SIGINT
, SIG_DFL
);
86 if (python_state
!= PYTHON_STATE_NOT_INITED
) {
91 * User can disable Python plugin support with the
92 * BABELTRACE_DISABLE_PYTHON_PLUGINS environment variable set to
95 dis_python_env
= getenv("BABELTRACE_DISABLE_PYTHON_PLUGINS");
96 if (dis_python_env
&& strcmp(dis_python_env
, "1") == 0) {
97 BT_LOGI_STR("Python plugin support is disabled because `BABELTRACE_DISABLE_PYTHON_PLUGINS=1`.");
98 python_state
= PYTHON_STATE_CANNOT_INITIALIZE
;
102 if (!Py_IsInitialized()) {
103 BT_LOGI_STR("Python interpreter is not initialized: initializing Python interpreter.");
105 python_was_initialized_by_us
= true;
106 BT_LOGI("Initialized Python interpreter: version=\"%s\"",
109 BT_LOGI("Python interpreter is already initialized: version=\"%s\"",
113 py_bt2_py_plugin_mod
= PyImport_ImportModule("bt2.py_plugin");
114 if (!py_bt2_py_plugin_mod
) {
115 BT_LOGI_STR("Cannot import bt2.py_plugin Python module: Python plugin support is disabled.");
116 python_state
= PYTHON_STATE_CANNOT_INITIALIZE
;
120 py_try_load_plugin_module_func
=
121 PyObject_GetAttrString(py_bt2_py_plugin_mod
, "_try_load_plugin_module");
122 if (!py_try_load_plugin_module_func
) {
123 BT_LOGI_STR("Cannot get _try_load_plugin_module attribute from bt2.py_plugin Python module: Python plugin support is disabled.");
124 python_state
= PYTHON_STATE_CANNOT_INITIALIZE
;
128 python_state
= PYTHON_STATE_FULLY_INITIALIZED
;
132 if (old_sigint
!= SIG_ERR
) {
133 (void) signal(SIGINT
, old_sigint
);
137 print_python_traceback_warn();
139 Py_XDECREF(py_bt2_py_plugin_mod
);
143 __attribute__((destructor
)) static
144 void fini_python(void) {
145 if (Py_IsInitialized() && python_was_initialized_by_us
) {
146 if (py_try_load_plugin_module_func
) {
147 Py_DECREF(py_try_load_plugin_module_func
);
148 py_try_load_plugin_module_func
= NULL
;
152 BT_LOGI_STR("Finalized Python interpreter.");
155 python_state
= PYTHON_STATE_NOT_INITED
;
159 bt_plugin
*bt_plugin_from_python_plugin_info(PyObject
*plugin_info
)
161 bt_plugin
*plugin
= NULL
;
162 PyObject
*py_name
= NULL
;
163 PyObject
*py_author
= NULL
;
164 PyObject
*py_description
= NULL
;
165 PyObject
*py_license
= NULL
;
166 PyObject
*py_version
= NULL
;
167 PyObject
*py_comp_class_addrs
= NULL
;
168 const char *name
= NULL
;
169 const char *author
= NULL
;
170 const char *description
= NULL
;
171 const char *license
= NULL
;
172 unsigned int major
= 0, minor
= 0, patch
= 0;
173 const char *version_extra
= NULL
;
176 BT_ASSERT(plugin_info
);
177 BT_ASSERT(python_state
== PYTHON_STATE_FULLY_INITIALIZED
);
178 py_name
= PyObject_GetAttrString(plugin_info
, "name");
180 BT_LOGW("Cannot find `name` attribute in Python plugin info object: "
181 "py-plugin-info-addr=%p", plugin_info
);
185 py_author
= PyObject_GetAttrString(plugin_info
, "author");
187 BT_LOGW("Cannot find `author` attribute in Python plugin info object: "
188 "py-plugin-info-addr=%p", plugin_info
);
192 py_description
= PyObject_GetAttrString(plugin_info
, "description");
193 if (!py_description
) {
194 BT_LOGW("Cannot find `desciption` attribute in Python plugin info object: "
195 "py-plugin-info-addr=%p", plugin_info
);
199 py_license
= PyObject_GetAttrString(plugin_info
, "license");
201 BT_LOGW("Cannot find `license` attribute in Python plugin info object: "
202 "py-plugin-info-addr=%p", plugin_info
);
206 py_version
= PyObject_GetAttrString(plugin_info
, "version");
208 BT_LOGW("Cannot find `version` attribute in Python plugin info object: "
209 "py-plugin-info-addr=%p", plugin_info
);
213 py_comp_class_addrs
= PyObject_GetAttrString(plugin_info
,
215 if (!py_comp_class_addrs
) {
216 BT_LOGW("Cannot find `comp_class_addrs` attribute in Python plugin info object: "
217 "py-plugin-info-addr=%p", plugin_info
);
221 if (PyUnicode_Check(py_name
)) {
222 name
= PyUnicode_AsUTF8(py_name
);
224 BT_LOGW("Cannot decode Python plugin name string: "
225 "py-plugin-info-addr=%p", plugin_info
);
229 /* Plugin name is mandatory */
230 BT_LOGW("Plugin name is not a string: "
231 "py-plugin-info-addr=%p", plugin_info
);
235 if (PyUnicode_Check(py_author
)) {
236 author
= PyUnicode_AsUTF8(py_author
);
238 BT_LOGW("Cannot decode Python plugin author string: "
239 "py-plugin-info-addr=%p", plugin_info
);
244 if (PyUnicode_Check(py_description
)) {
245 description
= PyUnicode_AsUTF8(py_description
);
247 BT_LOGW("Cannot decode Python plugin description string: "
248 "py-plugin-info-addr=%p", plugin_info
);
253 if (PyUnicode_Check(py_license
)) {
254 license
= PyUnicode_AsUTF8(py_license
);
256 BT_LOGW("Cannot decode Python plugin license string: "
257 "py-plugin-info-addr=%p", plugin_info
);
262 if (PyTuple_Check(py_version
)) {
263 if (PyTuple_Size(py_version
) >= 3) {
264 PyObject
*py_major
= PyTuple_GetItem(py_version
, 0);
265 PyObject
*py_minor
= PyTuple_GetItem(py_version
, 1);
266 PyObject
*py_patch
= PyTuple_GetItem(py_version
, 2);
272 if (PyLong_Check(py_major
)) {
273 major
= PyLong_AsUnsignedLong(py_major
);
276 if (PyLong_Check(py_minor
)) {
277 minor
= PyLong_AsUnsignedLong(py_minor
);
280 if (PyLong_Check(py_patch
)) {
281 patch
= PyLong_AsUnsignedLong(py_patch
);
284 if (PyErr_Occurred()) {
285 /* Overflow error, most probably */
286 BT_LOGW("Invalid Python plugin version format: "
287 "py-plugin-info-addr=%p", plugin_info
);
292 if (PyTuple_Size(py_version
) >= 4) {
293 PyObject
*py_extra
= PyTuple_GetItem(py_version
, 3);
297 if (PyUnicode_Check(py_extra
)) {
298 version_extra
= PyUnicode_AsUTF8(py_extra
);
299 if (!version_extra
) {
300 BT_LOGW("Cannot decode Python plugin version's extra string: "
301 "py-plugin-info-addr=%p", plugin_info
);
308 plugin
= bt_plugin_create_empty(BT_PLUGIN_TYPE_PYTHON
);
310 BT_LOGE_STR("Cannot create empty plugin object.");
314 bt_plugin_set_name(plugin
, name
);
317 bt_plugin_set_description(plugin
, description
);
321 bt_plugin_set_author(plugin
, author
);
325 bt_plugin_set_license(plugin
, license
);
328 bt_plugin_set_version(plugin
, major
, minor
, patch
, version_extra
);
330 if (PyList_Check(py_comp_class_addrs
)) {
333 for (i
= 0; i
< PyList_Size(py_comp_class_addrs
); i
++) {
334 bt_component_class
*comp_class
;
335 PyObject
*py_comp_class_addr
;
338 PyList_GetItem(py_comp_class_addrs
, i
);
339 BT_ASSERT(py_comp_class_addr
);
340 if (PyLong_Check(py_comp_class_addr
)) {
341 comp_class
= PyLong_AsVoidPtr(py_comp_class_addr
);
343 BT_LOGW("Component class address is not an integer in Python plugin info object: "
344 "py-plugin-info-addr=%p, index=%zu",
349 ret
= bt_plugin_add_component_class(plugin
, comp_class
);
351 BT_LOGE("Cannot add component class to plugin: "
352 "py-plugin-info-addr=%p, "
353 "plugin-addr=%p, plugin-name=\"%s\", "
354 "comp-class-addr=%p, "
355 "comp-class-name=\"%s\", "
356 "comp-class-type=%s",
358 plugin
, bt_plugin_get_name(plugin
),
360 bt_component_class_get_name(comp_class
),
361 bt_component_class_type_string(
362 bt_component_class_get_type(comp_class
)));
371 print_python_traceback_warn();
373 BT_OBJECT_PUT_REF_AND_RESET(plugin
);
377 Py_XDECREF(py_author
);
378 Py_XDECREF(py_description
);
379 Py_XDECREF(py_license
);
380 Py_XDECREF(py_version
);
381 Py_XDECREF(py_comp_class_addrs
);
386 bt_plugin_set
*bt_plugin_python_create_all_from_file(const char *path
)
388 bt_plugin_set
*plugin_set
= NULL
;
389 bt_plugin
*plugin
= NULL
;
390 PyObject
*py_plugin_info
= NULL
;
391 gchar
*basename
= NULL
;
396 if (python_state
== PYTHON_STATE_CANNOT_INITIALIZE
) {
398 * We do not even care about the rest of the function
399 * here because we already know Python cannot be fully
405 BT_LOGD("Creating all Python plugins from file: path=\"%s\"", path
);
406 path_len
= strlen(path
);
408 /* File name ends with `.py` */
409 if (strncmp(path
+ path_len
- PYTHON_PLUGIN_FILE_EXT_LEN
,
410 PYTHON_PLUGIN_FILE_EXT
,
411 PYTHON_PLUGIN_FILE_EXT_LEN
) != 0) {
412 BT_LOGD("Skipping non-Python file: path=\"%s\"", path
);
416 /* File name starts with `bt_plugin_` */
417 basename
= g_path_get_basename(path
);
419 BT_LOGW("Cannot get path's basename: path=\"%s\"", path
);
423 if (strncmp(basename
, PYTHON_PLUGIN_FILE_PREFIX
,
424 PYTHON_PLUGIN_FILE_PREFIX_LEN
) != 0) {
425 BT_LOGD("Skipping Python file not starting with `%s`: "
426 "path=\"%s\"", PYTHON_PLUGIN_FILE_PREFIX
, path
);
431 * Initialize Python now.
433 * This is not done in the library contructor because the
434 * interpreter is somewhat slow to initialize. If you don't
435 * have any potential Python plugins, you don't need to endure
436 * this waiting time everytime you load the library.
439 if (python_state
!= PYTHON_STATE_FULLY_INITIALIZED
) {
441 * For some reason we cannot initialize Python,
442 * import the required modules, and get the required
443 * attributes from them.
445 BT_LOGI("Failed to initialize Python interpreter.");
450 * Call bt2.py_plugin._try_load_plugin_module() with this path
451 * to get plugin info if the plugin is loadable and complete.
452 * This function returns None when there's an error, but just in
453 * case we also manually clear the last Python error state.
455 BT_LOGD_STR("Getting Python plugin info object from Python module.");
456 py_plugin_info
= PyObject_CallFunction(py_try_load_plugin_module_func
,
458 if (!py_plugin_info
|| py_plugin_info
== Py_None
) {
459 BT_LOGW("Cannot load Python plugin: path=\"%s\"", path
);
460 print_python_traceback_warn();
466 * Get bt_plugin from plugin info object.
468 plugin
= bt_plugin_from_python_plugin_info(py_plugin_info
);
470 BT_LOGW("Cannot create plugin object from Python plugin info object: "
471 "path=\"%s\", py-plugin-info-addr=%p",
472 path
, py_plugin_info
);
476 bt_plugin_set_path(plugin
, path
);
477 plugin_set
= bt_plugin_set_create();
479 BT_LOGE_STR("Cannot create empty plugin set.");
483 bt_plugin_set_add_plugin(plugin_set
, plugin
);
484 BT_LOGD("Created all Python plugins from file: path=\"%s\", "
485 "plugin-addr=%p, plugin-name=\"%s\"",
486 path
, plugin
, bt_plugin_get_name(plugin
));
490 BT_OBJECT_PUT_REF_AND_RESET(plugin_set
);
493 bt_plugin_put_ref(plugin
);
494 Py_XDECREF(py_plugin_info
);