[babeltrace.git] / src / bindings / python / bt2 / bt2 / native_bt_log_and_append_error.h

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdbool.h>

#include "logging/comp-logging.h"

static
void restore_current_thread_error_and_append_exception_chain_recursive(
		int active_log_level, PyObject *py_exc_value,
		bt_self_component_class *self_component_class,
		bt_self_component *self_component,
		bt_self_message_iterator *self_message_iterator,
		const char *module_name)
{
	PyObject *py_exc_cause_value;
	PyObject *py_exc_type = NULL;
	PyObject *py_exc_tb = NULL;
	PyObject *py_bt_error_msg = NULL;
	GString *gstr = NULL;

	/* If this exception has a (Python) cause, handle that one first. */
	py_exc_cause_value = PyException_GetCause(py_exc_value);
	if (py_exc_cause_value) {
		restore_current_thread_error_and_append_exception_chain_recursive(
			active_log_level, py_exc_cause_value,
			self_component_class, self_component,
			self_message_iterator, module_name);
	}

	py_exc_tb = PyException_GetTraceback(py_exc_value);

	if (PyErr_GivenExceptionMatches(py_exc_value, py_mod_bt2_exc_error_type)) {
		/*
		 * If the raised exception is a bt2._Error, restore the wrapped
		 * error.
		 */
		PyObject *py_error_swig_ptr;
		const bt_error *error;
		int ret;

		/*
		 * We never raise a bt2._Error with a (Python) cause: it should
		 * be the end of the chain.
		 */
		BT_ASSERT(!py_exc_cause_value);

		/*
		 * We steal the error object from the exception, to move
		 * it back as the current thread's error.
		 */
		py_error_swig_ptr = PyObject_GetAttrString(py_exc_value, "_ptr");
		BT_ASSERT(py_error_swig_ptr);

		ret = PyObject_SetAttrString(py_exc_value, "_ptr", Py_None);
		BT_ASSERT(ret == 0);

		ret = SWIG_ConvertPtr(py_error_swig_ptr, (void **) &error,
			SWIGTYPE_p_bt_error, 0);
		BT_ASSERT(ret == 0);

		Py_DECREF(py_error_swig_ptr);

		BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(error);

		/*
		 * Append a cause with just the traceback and message, not the
		 * full str() of the bt2._Error.  We don't want the causes of
		 * this bt2._Error to be included in the cause we create.
		 */
		gstr = bt_py_common_format_tb(py_exc_tb, active_log_level);
		if (!gstr) {
			/* bt_py_common_format_tb has already warned. */
			goto end;
		}

		g_string_prepend(gstr, "Traceback (most recent call last):\n");

		py_bt_error_msg = PyObject_GetAttrString(py_exc_value, "_msg");
		BT_ASSERT(py_bt_error_msg);

		g_string_append_printf(gstr, "\nbt2._Error: %s",
			PyUnicode_AsUTF8(py_bt_error_msg));
	} else {
		py_exc_type = PyObject_Type(py_exc_value);

		gstr = bt_py_common_format_exception(py_exc_type, py_exc_value,
				py_exc_tb, active_log_level, false);
		if (!gstr) {
			/* bt_py_common_format_exception has already warned. */
			goto end;
		}
	}

	if (self_component_class) {
		BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT_CLASS(
			self_component_class, "%s", gstr->str);
	} else if (self_component) {
		BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(
			self_component, "%s", gstr->str);
	} else if (self_message_iterator) {
		BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
			self_message_iterator, "%s", gstr->str);
	} else {
		BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
			module_name, "%s", gstr->str);
	}

end:
	if (gstr) {
		g_string_free(gstr, TRUE);
	}

	Py_XDECREF(py_exc_cause_value);
	Py_XDECREF(py_exc_type);
	Py_XDECREF(py_exc_tb);
	Py_XDECREF(py_bt_error_msg);
}

/*
 * If you have the following code:
 *
 * try:
 *     try:
 *         something_that_raises_bt2_error()
 *     except bt2._Error as e1:
 *         raise ValueError from e1
 * except ValueError as e2:
 *     raise TypeError from e2
 *
 * We will have the following exception chain:
 *
 *     TypeError -> ValueError -> bt2._Error
 *
 * Where the TypeError is the current exception (obtained from PyErr_Fetch).
 *
 * The bt2._Error contains a `struct bt_error *` that used to be the current
 * thread's error, at the moment the exception was raised.
 *
 * This function gets to the bt2._Error and restores the wrapped
 * `struct bt_error *` as the current thread's error.
 *
 * Then, for each exception in the chain, starting with the oldest one, it adds
 * an error cause to the current thread's error.
 */
static
void restore_bt_error_and_append_current_exception_chain(
		int active_log_level,
		bt_self_component_class *self_component_class,
		bt_self_component *self_component,
		bt_self_message_iterator *self_message_iterator,
		const char *module_name)
{
	BT_ASSERT(PyErr_Occurred());

	/* Used to access and restore the current exception. */
	PyObject *py_exc_type;
	PyObject *py_exc_value;
	PyObject *py_exc_tb;

	/* Fetch and normalize the Python exception. */
	PyErr_Fetch(&py_exc_type, &py_exc_value, &py_exc_tb);
	PyErr_NormalizeException(&py_exc_type, &py_exc_value, &py_exc_tb);
	BT_ASSERT(py_exc_type);
	BT_ASSERT(py_exc_value);
	BT_ASSERT(py_exc_tb);

	/*
	 * Set the exception's traceback so it's possible to get it using
	 * PyException_GetTraceback in
	 * restore_current_thread_error_and_append_exception_chain_recursive.
	 */
	PyException_SetTraceback(py_exc_value, py_exc_tb);

	restore_current_thread_error_and_append_exception_chain_recursive(
		active_log_level, py_exc_value, self_component_class,
		self_component, self_message_iterator, module_name);

	PyErr_Restore(py_exc_type, py_exc_value, py_exc_tb);
}

static inline
void log_exception_and_maybe_append_cause(
		int func_log_level,
		int active_log_level,
		bool append_error,
		bt_self_component_class *self_component_class,
		bt_self_component *self_component,
		bt_self_message_iterator *self_message_iterator,
		const char *module_name)
{
	GString *gstr;

	BT_ASSERT(PyErr_Occurred());
	gstr = bt_py_common_format_current_exception(active_log_level);
	if (!gstr) {
		/* bt_py_common_format_current_exception() logs errors */
		goto end;
	}

	BT_COMP_LOG_CUR_LVL(func_log_level, active_log_level, self_component,
		"%s", gstr->str);

	if (append_error) {
		restore_bt_error_and_append_current_exception_chain(
			active_log_level, self_component_class, self_component,
			self_message_iterator, module_name);

	}

end:
	if (gstr) {
		g_string_free(gstr, TRUE);
	}
}

static
bt_logging_level get_self_component_log_level(bt_self_component *self_comp)
{
	return bt_component_get_logging_level(
		bt_self_component_as_component(self_comp));
}

static
bt_logging_level get_self_message_iterator_log_level(
		bt_self_message_iterator *self_msg_iter)
{
	bt_self_component *self_comp =
		bt_self_message_iterator_borrow_component(self_msg_iter);

	return get_self_component_log_level(self_comp);
}

static inline
void loge_exception_append_cause_clear(const char *module_name, int active_log_level)
{
	log_exception_and_maybe_append_cause(BT_LOG_ERROR, active_log_level,
		true, NULL, NULL, NULL, module_name);
	PyErr_Clear();
}

static inline
void logw_exception_clear(int active_log_level)
{
	log_exception_and_maybe_append_cause(BT_LOG_WARNING, active_log_level,
		false, NULL, NULL, NULL, NULL);
	PyErr_Clear();
}
Commit	Line	Data
65e28173 PP	1	/*
	2	* The MIT License (MIT)
	3	*
	4	* Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a copy
	7	* of this software and associated documentation files (the "Software"), to deal
	8	* in the Software without restriction, including without limitation the rights
	9	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	10	* copies of the Software, and to permit persons to whom the Software is
	11	* furnished to do so, subject to the following conditions:
	12	*
	13	* The above copyright notice and this permission notice shall be included in
	14	* all copies or substantial portions of the Software.
	15	*
	16	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	17	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	18	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	19	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	20	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	21	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	22	* THE SOFTWARE.
	23	*/
	24
969c1d8a FD	25	#include <stdbool.h>
969c1d8a FD	26
65e28173 PP	27	#include "logging/comp-logging.h"
	28
	29	static
	30	void restore_current_thread_error_and_append_exception_chain_recursive(
	31	int active_log_level, PyObject *py_exc_value,
	32	bt_self_component_class *self_component_class,
	33	bt_self_component *self_component,
	34	bt_self_message_iterator *self_message_iterator,
	35	const char *module_name)
	36	{
	37	PyObject *py_exc_cause_value;
	38	PyObject *py_exc_type = NULL;
	39	PyObject *py_exc_tb = NULL;
b53cd768	40	PyObject *py_bt_error_msg = NULL;
65e28173 PP	41	GString *gstr = NULL;
65e28173 PP	42
b53cd768	43	/* If this exception has a (Python) cause, handle that one first. */
65e28173 PP	44	py_exc_cause_value = PyException_GetCause(py_exc_value);
	45	if (py_exc_cause_value) {
	46	restore_current_thread_error_and_append_exception_chain_recursive(
	47	active_log_level, py_exc_cause_value,
	48	self_component_class, self_component,
	49	self_message_iterator, module_name);
	50	}
	51
b53cd768 SM	52	py_exc_tb = PyException_GetTraceback(py_exc_value);
b53cd768 SM	53
65e28173	54	if (PyErr_GivenExceptionMatches(py_exc_value, py_mod_bt2_exc_error_type)) {
b53cd768 SM	55	/*
	56	* If the raised exception is a bt2._Error, restore the wrapped
	57	* error.
	58	*/
65e28173 PP	59	PyObject *py_error_swig_ptr;
	60	const bt_error *error;
	61	int ret;
	62
	63	/*
b53cd768 SM	64	* We never raise a bt2._Error with a (Python) cause: it should
b53cd768 SM	65	* be the end of the chain.
65e28173 PP	66	*/
	67	BT_ASSERT(!py_exc_cause_value);
	68
	69	/*
	70	* We steal the error object from the exception, to move
	71	* it back as the current thread's error.
	72	*/
	73	py_error_swig_ptr = PyObject_GetAttrString(py_exc_value, "_ptr");
	74	BT_ASSERT(py_error_swig_ptr);
	75
	76	ret = PyObject_SetAttrString(py_exc_value, "_ptr", Py_None);
	77	BT_ASSERT(ret == 0);
	78
	79	ret = SWIG_ConvertPtr(py_error_swig_ptr, (void **) &error,
	80	SWIGTYPE_p_bt_error, 0);
	81	BT_ASSERT(ret == 0);
	82
b53cd768 SM	83	Py_DECREF(py_error_swig_ptr);
b53cd768 SM	84
65e28173 PP	85	BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(error);
65e28173 PP	86
b53cd768 SM	87	/*
	88	* Append a cause with just the traceback and message, not the
	89	* full str() of the bt2._Error. We don't want the causes of
	90	* this bt2._Error to be included in the cause we create.
	91	*/
	92	gstr = bt_py_common_format_tb(py_exc_tb, active_log_level);
	93	if (!gstr) {
	94	/* bt_py_common_format_tb has already warned. */
	95	goto end;
	96	}
65e28173	97
b53cd768 SM	98	g_string_prepend(gstr, "Traceback (most recent call last):\n");
	99
	100	py_bt_error_msg = PyObject_GetAttrString(py_exc_value, "_msg");
	101	BT_ASSERT(py_bt_error_msg);
65e28173	102
b53cd768 SM	103	g_string_append_printf(gstr, "\nbt2._Error: %s",
	104	PyUnicode_AsUTF8(py_bt_error_msg));
	105	} else {
	106	py_exc_type = PyObject_Type(py_exc_value);
	107
	108	gstr = bt_py_common_format_exception(py_exc_type, py_exc_value,
	109	py_exc_tb, active_log_level, false);
	110	if (!gstr) {
	111	/* bt_py_common_format_exception has already warned. */
	112	goto end;
	113	}
65e28173 PP	114	}
	115
	116	if (self_component_class) {
	117	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT_CLASS(
	118	self_component_class, "%s", gstr->str);
	119	} else if (self_component) {
	120	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(
	121	self_component, "%s", gstr->str);
	122	} else if (self_message_iterator) {
	123	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
	124	self_message_iterator, "%s", gstr->str);
	125	} else {
	126	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
	127	module_name, "%s", gstr->str);
	128	}
	129
	130	end:
	131	if (gstr) {
	132	g_string_free(gstr, TRUE);
	133	}
	134
	135	Py_XDECREF(py_exc_cause_value);
	136	Py_XDECREF(py_exc_type);
	137	Py_XDECREF(py_exc_tb);
b53cd768	138	Py_XDECREF(py_bt_error_msg);
65e28173 PP	139	}
	140
	141	/*
	142	* If you have the following code:
	143	*
	144	* try:
	145	* try:
	146	* something_that_raises_bt2_error()
	147	* except bt2._Error as e1:
	148	* raise ValueError from e1
	149	* except ValueError as e2:
	150	* raise TypeError from e2
	151	*
	152	* We will have the following exception chain:
	153	*
	154	* TypeError -> ValueError -> bt2._Error
	155	*
	156	* Where the TypeError is the current exception (obtained from PyErr_Fetch).
	157	*
	158	* The bt2._Error contains a `struct bt_error *` that used to be the current
	159	* thread's error, at the moment the exception was raised.
	160	*
	161	* This function gets to the bt2._Error and restores the wrapped
	162	* `struct bt_error *` as the current thread's error.
	163	*
	164	* Then, for each exception in the chain, starting with the oldest one, it adds
	165	* an error cause to the current thread's error.
	166	*/
	167	static
	168	void restore_bt_error_and_append_current_exception_chain(
	169	int active_log_level,
	170	bt_self_component_class *self_component_class,
	171	bt_self_component *self_component,
	172	bt_self_message_iterator *self_message_iterator,
	173	const char *module_name)
	174	{
	175	BT_ASSERT(PyErr_Occurred());
	176
	177	/* Used to access and restore the current exception. */
	178	PyObject *py_exc_type;
	179	PyObject *py_exc_value;
	180	PyObject *py_exc_tb;
	181
	182	/* Fetch and normalize the Python exception. */
	183	PyErr_Fetch(&py_exc_type, &py_exc_value, &py_exc_tb);
	184	PyErr_NormalizeException(&py_exc_type, &py_exc_value, &py_exc_tb);
	185	BT_ASSERT(py_exc_type);
	186	BT_ASSERT(py_exc_value);
	187	BT_ASSERT(py_exc_tb);
	188
	189	/*
	190	* Set the exception's traceback so it's possible to get it using
	191	* PyException_GetTraceback in
	192	* restore_current_thread_error_and_append_exception_chain_recursive.
	193	*/
	194	PyException_SetTraceback(py_exc_value, py_exc_tb);
	195
	196	restore_current_thread_error_and_append_exception_chain_recursive(
	197	active_log_level, py_exc_value, self_component_class,
	198	self_component, self_message_iterator, module_name);
	199
	200	PyErr_Restore(py_exc_type, py_exc_value, py_exc_tb);
	201	}
	202
203	static inline
27ba49f1 SM	204	void log_exception_and_maybe_append_cause(
	205	int func_log_level,
	206	int active_log_level,
	207	bool append_error,
65e28173 PP	208	bt_self_component_class *self_component_class,
	209	bt_self_component *self_component,
	210	bt_self_message_iterator *self_message_iterator,
	211	const char *module_name)
	212	{
	213	GString *gstr;
	214
	215	BT_ASSERT(PyErr_Occurred());
	216	gstr = bt_py_common_format_current_exception(active_log_level);
	217	if (!gstr) {
	218	/* bt_py_common_format_current_exception() logs errors */
	219	goto end;
	220	}
	221
	222	BT_COMP_LOG_CUR_LVL(func_log_level, active_log_level, self_component,
	223	"%s", gstr->str);
	224
	225	if (append_error) {
	226	restore_bt_error_and_append_current_exception_chain(
	227	active_log_level, self_component_class, self_component,
	228	self_message_iterator, module_name);
	229
	230	}
	231
	232	end:
	233	if (gstr) {
	234	g_string_free(gstr, TRUE);
	235	}
	236	}
	237
	238	static
	239	bt_logging_level get_self_component_log_level(bt_self_component *self_comp)
	240	{
	241	return bt_component_get_logging_level(
	242	bt_self_component_as_component(self_comp));
	243	}
	244
	245	static
	246	bt_logging_level get_self_message_iterator_log_level(
	247	bt_self_message_iterator *self_msg_iter)
	248	{
	249	bt_self_component *self_comp =
	250	bt_self_message_iterator_borrow_component(self_msg_iter);
	251
	252	return get_self_component_log_level(self_comp);
	253	}
	254
	255	static inline
c7cc9a2a	256	void loge_exception_append_cause_clear(const char *module_name, int active_log_level)
65e28173	257	{
27ba49f1	258	log_exception_and_maybe_append_cause(BT_LOG_ERROR, active_log_level,
65e28173	259	true, NULL, NULL, NULL, module_name);
c7cc9a2a	260	PyErr_Clear();
65e28173 PP	261	}
65e28173 PP	262
65e28173	263	static inline
c7cc9a2a	264	void logw_exception_clear(int active_log_level)
65e28173	265	{
27ba49f1	266	log_exception_and_maybe_append_cause(BT_LOG_WARNING, active_log_level,
65e28173	267	false, NULL, NULL, NULL, NULL);
c7cc9a2a	268	PyErr_Clear();
65e28173	269	}