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"
30 #include <babeltrace/babeltrace-internal.h>
31 #include <babeltrace/compiler-internal.h>
32 #include <babeltrace/ref.h>
33 #include <babeltrace/plugin/plugin.h>
34 #include <babeltrace/plugin/plugin-internal.h>
35 #include <babeltrace/graph/component-class.h>
36 #include <babeltrace/graph/component-class-internal.h>
43 #define PYTHON_PLUGIN_FILE_PREFIX "bt_plugin_"
44 #define PYTHON_PLUGIN_FILE_PREFIX_LEN (sizeof(PYTHON_PLUGIN_FILE_PREFIX) - 1)
45 #define PYTHON_PLUGIN_FILE_EXT ".py"
46 #define PYTHON_PLUGIN_FILE_EXT_LEN (sizeof(PYTHON_PLUGIN_FILE_EXT) - 1)
49 /* init_python() not called yet */
50 PYTHON_STATE_NOT_INITED
,
52 /* init_python() called once with success */
53 PYTHON_STATE_FULLY_INITIALIZED
,
55 /* init_python() called once without success */
56 PYTHON_STATE_CANNOT_INITIALIZE
,
57 } python_state
= PYTHON_STATE_NOT_INITED
;
59 static PyObject
*py_try_load_plugin_module_func
= NULL
;
60 static bool python_was_initialized_by_us
;
63 void print_python_traceback_warn(void)
65 if (BT_LOG_ON_WARN
&& Py_IsInitialized() && PyErr_Occurred()) {
66 BT_LOGW_STR("Exception occured: traceback: ");
72 void pyerr_clear(void)
74 if (Py_IsInitialized()) {
80 void init_python(void)
82 PyObject
*py_bt2_py_plugin_mod
= NULL
;
83 const char *dis_python_env
;
84 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
;
131 if (old_sigint
!= SIG_ERR
) {
132 (void) signal(SIGINT
, old_sigint
);
135 print_python_traceback_warn();
137 Py_XDECREF(py_bt2_py_plugin_mod
);
141 __attribute__((destructor
)) static
142 void fini_python(void) {
143 if (Py_IsInitialized() && python_was_initialized_by_us
) {
144 if (py_try_load_plugin_module_func
) {
145 Py_DECREF(py_try_load_plugin_module_func
);
146 py_try_load_plugin_module_func
= NULL
;
150 BT_LOGI_STR("Finalized Python interpreter.");
153 python_state
= PYTHON_STATE_NOT_INITED
;
157 struct bt_plugin
*bt_plugin_from_python_plugin_info(PyObject
*plugin_info
)
159 struct bt_plugin
*plugin
= NULL
;
160 PyObject
*py_name
= NULL
;
161 PyObject
*py_author
= NULL
;
162 PyObject
*py_description
= NULL
;
163 PyObject
*py_license
= NULL
;
164 PyObject
*py_version
= NULL
;
165 PyObject
*py_comp_class_addrs
= NULL
;
166 const char *name
= NULL
;
167 const char *author
= NULL
;
168 const char *description
= NULL
;
169 const char *license
= NULL
;
170 unsigned int major
= 0, minor
= 0, patch
= 0;
171 const char *version_extra
= NULL
;
175 assert(python_state
== PYTHON_STATE_FULLY_INITIALIZED
);
176 py_name
= PyObject_GetAttrString(plugin_info
, "name");
178 BT_LOGW("Cannot find `name` attribute in Python plugin info object: "
179 "py-plugin-info-addr=%p", plugin_info
);
183 py_author
= PyObject_GetAttrString(plugin_info
, "author");
185 BT_LOGW("Cannot find `author` attribute in Python plugin info object: "
186 "py-plugin-info-addr=%p", plugin_info
);
190 py_description
= PyObject_GetAttrString(plugin_info
, "description");
191 if (!py_description
) {
192 BT_LOGW("Cannot find `desciption` attribute in Python plugin info object: "
193 "py-plugin-info-addr=%p", plugin_info
);
197 py_license
= PyObject_GetAttrString(plugin_info
, "license");
199 BT_LOGW("Cannot find `license` attribute in Python plugin info object: "
200 "py-plugin-info-addr=%p", plugin_info
);
204 py_version
= PyObject_GetAttrString(plugin_info
, "version");
206 BT_LOGW("Cannot find `version` attribute in Python plugin info object: "
207 "py-plugin-info-addr=%p", plugin_info
);
211 py_comp_class_addrs
= PyObject_GetAttrString(plugin_info
,
213 if (!py_comp_class_addrs
) {
214 BT_LOGW("Cannot find `comp_class_addrs` attribute in Python plugin info object: "
215 "py-plugin-info-addr=%p", plugin_info
);
219 if (PyUnicode_Check(py_name
)) {
220 name
= PyUnicode_AsUTF8(py_name
);
222 BT_LOGW("Cannot decode Python plugin name string: "
223 "py-plugin-info-addr=%p", plugin_info
);
227 /* Plugin name is mandatory */
228 BT_LOGW("Plugin name is not a string: "
229 "py-plugin-info-addr=%p", plugin_info
);
233 if (PyUnicode_Check(py_author
)) {
234 author
= PyUnicode_AsUTF8(py_author
);
236 BT_LOGW("Cannot decode Python plugin author string: "
237 "py-plugin-info-addr=%p", plugin_info
);
242 if (PyUnicode_Check(py_description
)) {
243 description
= PyUnicode_AsUTF8(py_description
);
245 BT_LOGW("Cannot decode Python plugin description string: "
246 "py-plugin-info-addr=%p", plugin_info
);
251 if (PyUnicode_Check(py_license
)) {
252 license
= PyUnicode_AsUTF8(py_license
);
254 BT_LOGW("Cannot decode Python plugin license string: "
255 "py-plugin-info-addr=%p", plugin_info
);
260 if (PyTuple_Check(py_version
)) {
261 if (PyTuple_Size(py_version
) >= 3) {
262 PyObject
*py_major
= PyTuple_GetItem(py_version
, 0);
263 PyObject
*py_minor
= PyTuple_GetItem(py_version
, 1);
264 PyObject
*py_patch
= PyTuple_GetItem(py_version
, 2);
270 if (PyLong_Check(py_major
)) {
271 major
= PyLong_AsUnsignedLong(py_major
);
274 if (PyLong_Check(py_minor
)) {
275 minor
= PyLong_AsUnsignedLong(py_minor
);
278 if (PyLong_Check(py_patch
)) {
279 patch
= PyLong_AsUnsignedLong(py_patch
);
282 if (PyErr_Occurred()) {
283 /* Overflow error, most probably */
284 BT_LOGW("Invalid Python plugin version format: "
285 "py-plugin-info-addr=%p", plugin_info
);
290 if (PyTuple_Size(py_version
) >= 4) {
291 PyObject
*py_extra
= PyTuple_GetItem(py_version
, 3);
295 if (PyUnicode_Check(py_extra
)) {
296 version_extra
= PyUnicode_AsUTF8(py_extra
);
297 if (!version_extra
) {
298 BT_LOGW("Cannot decode Python plugin version's extra string: "
299 "py-plugin-info-addr=%p", plugin_info
);
306 plugin
= bt_plugin_create_empty(BT_PLUGIN_TYPE_PYTHON
);
308 BT_LOGE_STR("Cannot create empty plugin object.");
312 bt_plugin_set_name(plugin
, name
);
315 bt_plugin_set_description(plugin
, description
);
319 bt_plugin_set_author(plugin
, author
);
323 bt_plugin_set_license(plugin
, license
);
326 bt_plugin_set_version(plugin
, major
, minor
, patch
, version_extra
);
328 if (PyList_Check(py_comp_class_addrs
)) {
331 for (i
= 0; i
< PyList_Size(py_comp_class_addrs
); i
++) {
332 struct bt_component_class
*comp_class
;
333 PyObject
*py_comp_class_addr
;
336 PyList_GetItem(py_comp_class_addrs
, i
);
337 assert(py_comp_class_addr
);
338 if (PyLong_Check(py_comp_class_addr
)) {
339 comp_class
= (struct bt_component_class
*)
340 PyLong_AsUnsignedLongLong(py_comp_class_addr
);
342 BT_LOGW("Component class address is not an integer in Python plugin info object: "
343 "py-plugin-info-addr=%p, index=%zu",
348 ret
= bt_plugin_add_component_class(plugin
, comp_class
);
350 BT_LOGE("Cannot add component class to plugin: "
351 "py-plugin-info-addr=%p, "
352 "plugin-addr=%p, plugin-name=\"%s\", "
353 "comp-class-addr=%p, "
354 "comp-class-name=\"%s\", "
355 "comp-class-type=%s",
357 plugin
, bt_plugin_get_name(plugin
),
359 bt_component_class_get_name(comp_class
),
360 bt_component_class_type_string(
361 bt_component_class_get_type(comp_class
)));
367 bt_plugin_freeze(plugin
);
372 print_python_traceback_warn();
378 Py_XDECREF(py_author
);
379 Py_XDECREF(py_description
);
380 Py_XDECREF(py_license
);
381 Py_XDECREF(py_version
);
382 Py_XDECREF(py_comp_class_addrs
);
387 struct bt_plugin_set
*bt_plugin_python_create_all_from_file(const char *path
)
389 struct bt_plugin_set
*plugin_set
= NULL
;
390 struct bt_plugin
*plugin
= NULL
;
391 PyObject
*py_plugin_info
= NULL
;
392 gchar
*basename
= NULL
;
397 if (python_state
== PYTHON_STATE_CANNOT_INITIALIZE
) {
399 * We do not even care about the rest of the function
400 * here because we already know Python cannot be fully
406 BT_LOGD("Creating all Python plugins from file: path=\"%s\"", path
);
407 path_len
= strlen(path
);
409 /* File name ends with `.py` */
410 if (strncmp(path
+ path_len
- PYTHON_PLUGIN_FILE_EXT_LEN
,
411 PYTHON_PLUGIN_FILE_EXT
,
412 PYTHON_PLUGIN_FILE_EXT_LEN
) != 0) {
413 BT_LOGD("Skipping non-Python file: path=\"%s\"", path
);
417 /* File name starts with `bt_plugin_` */
418 basename
= g_path_get_basename(path
);
420 BT_LOGW("Cannot get path's basename: path=\"%s\"", path
);
424 if (strncmp(basename
, PYTHON_PLUGIN_FILE_PREFIX
,
425 PYTHON_PLUGIN_FILE_PREFIX_LEN
) != 0) {
426 BT_LOGD("Skipping Python file not starting with `%s`: "
427 "path=\"%s\"", PYTHON_PLUGIN_FILE_PREFIX
, path
);
432 * Initialize Python now.
434 * This is not done in the library contructor because the
435 * interpreter is somewhat slow to initialize. If you don't
436 * have any potential Python plugins, you don't need to endure
437 * this waiting time everytime you load the library.
440 if (python_state
!= PYTHON_STATE_FULLY_INITIALIZED
) {
442 * For some reason we cannot initialize Python,
443 * import the required modules, and get the required
444 * attributes from them.
446 BT_LOGI("Failed to initialize Python interpreter.");
451 * Call bt2.py_plugin._try_load_plugin_module() with this path
452 * to get plugin info if the plugin is loadable and complete.
453 * This function returns None when there's an error, but just in
454 * case we also manually clear the last Python error state.
456 BT_LOGD_STR("Getting Python plugin info object from Python module.");
457 py_plugin_info
= PyObject_CallFunction(py_try_load_plugin_module_func
,
459 if (!py_plugin_info
|| py_plugin_info
== Py_None
) {
460 BT_LOGW("Cannot load Python plugin: path=\"%s\"", path
);
461 print_python_traceback_warn();
467 * Get bt_plugin from plugin info object.
469 plugin
= bt_plugin_from_python_plugin_info(py_plugin_info
);
471 BT_LOGW("Cannot create plugin object from Python plugin info object: "
472 "path=\"%s\", py-plugin-info-addr=%p",
473 path
, py_plugin_info
);
477 bt_plugin_set_path(plugin
, path
);
478 plugin_set
= bt_plugin_set_create();
480 BT_LOGE_STR("Cannot create empty plugin set.");
484 bt_plugin_set_add_plugin(plugin_set
, plugin
);
485 BT_LOGD("Created all Python plugins from file: path=\"%s\", "
486 "plugin-addr=%p, plugin-name=\"%s\"",
487 path
, plugin
, bt_plugin_get_name(plugin
));
495 Py_XDECREF(py_plugin_info
);