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

/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
 */

#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
612a9870	1	/*
0235b0db	2	* SPDX-License-Identifier: MIT
612a9870 PP	3	*
612a9870 PP	4	* Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
612a9870 PP	5	*/
612a9870 PP	6
c4f23e30 FD	7	#include <stdbool.h>
c4f23e30 FD	8
612a9870 PP	9	#include "logging/comp-logging.h"
	10
	11	static
	12	void restore_current_thread_error_and_append_exception_chain_recursive(
	13	int active_log_level, PyObject *py_exc_value,
	14	bt_self_component_class *self_component_class,
	15	bt_self_component *self_component,
	16	bt_self_message_iterator *self_message_iterator,
	17	const char *module_name)
	18	{
	19	PyObject *py_exc_cause_value;
	20	PyObject *py_exc_type = NULL;
	21	PyObject *py_exc_tb = NULL;
332c7e11	22	PyObject *py_bt_error_msg = NULL;
612a9870 PP	23	GString *gstr = NULL;
612a9870 PP	24
332c7e11	25	/* If this exception has a (Python) cause, handle that one first. */
612a9870 PP	26	py_exc_cause_value = PyException_GetCause(py_exc_value);
	27	if (py_exc_cause_value) {
	28	restore_current_thread_error_and_append_exception_chain_recursive(
	29	active_log_level, py_exc_cause_value,
	30	self_component_class, self_component,
	31	self_message_iterator, module_name);
	32	}
	33
332c7e11 SM	34	py_exc_tb = PyException_GetTraceback(py_exc_value);
332c7e11 SM	35
612a9870	36	if (PyErr_GivenExceptionMatches(py_exc_value, py_mod_bt2_exc_error_type)) {
332c7e11 SM	37	/*
	38	* If the raised exception is a bt2._Error, restore the wrapped
	39	* error.
	40	*/
612a9870 PP	41	PyObject *py_error_swig_ptr;
	42	const bt_error *error;
	43	int ret;
	44
	45	/*
332c7e11 SM	46	* We never raise a bt2._Error with a (Python) cause: it should
332c7e11 SM	47	* be the end of the chain.
612a9870 PP	48	*/
	49	BT_ASSERT(!py_exc_cause_value);
	50
	51	/*
	52	* We steal the error object from the exception, to move
	53	* it back as the current thread's error.
	54	*/
	55	py_error_swig_ptr = PyObject_GetAttrString(py_exc_value, "_ptr");
	56	BT_ASSERT(py_error_swig_ptr);
	57
	58	ret = PyObject_SetAttrString(py_exc_value, "_ptr", Py_None);
	59	BT_ASSERT(ret == 0);
	60
	61	ret = SWIG_ConvertPtr(py_error_swig_ptr, (void **) &error,
	62	SWIGTYPE_p_bt_error, 0);
	63	BT_ASSERT(ret == 0);
	64
332c7e11 SM	65	Py_DECREF(py_error_swig_ptr);
332c7e11 SM	66
612a9870 PP	67	BT_CURRENT_THREAD_MOVE_ERROR_AND_RESET(error);
612a9870 PP	68
332c7e11 SM	69	/*
	70	* Append a cause with just the traceback and message, not the
	71	* full str() of the bt2._Error. We don't want the causes of
	72	* this bt2._Error to be included in the cause we create.
	73	*/
	74	gstr = bt_py_common_format_tb(py_exc_tb, active_log_level);
	75	if (!gstr) {
	76	/* bt_py_common_format_tb has already warned. */
	77	goto end;
	78	}
612a9870	79
332c7e11 SM	80	g_string_prepend(gstr, "Traceback (most recent call last):\n");
	81
	82	py_bt_error_msg = PyObject_GetAttrString(py_exc_value, "_msg");
	83	BT_ASSERT(py_bt_error_msg);
612a9870	84
332c7e11 SM	85	g_string_append_printf(gstr, "\nbt2._Error: %s",
	86	PyUnicode_AsUTF8(py_bt_error_msg));
	87	} else {
	88	py_exc_type = PyObject_Type(py_exc_value);
	89
	90	gstr = bt_py_common_format_exception(py_exc_type, py_exc_value,
	91	py_exc_tb, active_log_level, false);
	92	if (!gstr) {
	93	/* bt_py_common_format_exception has already warned. */
	94	goto end;
	95	}
612a9870 PP	96	}
	97
	98	if (self_component_class) {
	99	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT_CLASS(
	100	self_component_class, "%s", gstr->str);
	101	} else if (self_component) {
	102	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(
	103	self_component, "%s", gstr->str);
	104	} else if (self_message_iterator) {
	105	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_MESSAGE_ITERATOR(
	106	self_message_iterator, "%s", gstr->str);
	107	} else {
	108	BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
	109	module_name, "%s", gstr->str);
	110	}
	111
	112	end:
	113	if (gstr) {
	114	g_string_free(gstr, TRUE);
	115	}
	116
	117	Py_XDECREF(py_exc_cause_value);
	118	Py_XDECREF(py_exc_type);
	119	Py_XDECREF(py_exc_tb);
332c7e11	120	Py_XDECREF(py_bt_error_msg);
612a9870 PP	121	}
	122
	123	/*
	124	* If you have the following code:
	125	*
	126	* try:
	127	* try:
	128	* something_that_raises_bt2_error()
	129	* except bt2._Error as e1:
	130	* raise ValueError from e1
	131	* except ValueError as e2:
	132	* raise TypeError from e2
	133	*
	134	* We will have the following exception chain:
	135	*
	136	* TypeError -> ValueError -> bt2._Error
	137	*
	138	* Where the TypeError is the current exception (obtained from PyErr_Fetch).
	139	*
	140	* The bt2._Error contains a `struct bt_error *` that used to be the current
	141	* thread's error, at the moment the exception was raised.
	142	*
	143	* This function gets to the bt2._Error and restores the wrapped
	144	* `struct bt_error *` as the current thread's error.
	145	*
	146	* Then, for each exception in the chain, starting with the oldest one, it adds
	147	* an error cause to the current thread's error.
	148	*/
	149	static
	150	void restore_bt_error_and_append_current_exception_chain(
	151	int active_log_level,
	152	bt_self_component_class *self_component_class,
	153	bt_self_component *self_component,
	154	bt_self_message_iterator *self_message_iterator,
	155	const char *module_name)
	156	{
	157	BT_ASSERT(PyErr_Occurred());
	158
	159	/* Used to access and restore the current exception. */
	160	PyObject *py_exc_type;
	161	PyObject *py_exc_value;
	162	PyObject *py_exc_tb;
	163
	164	/* Fetch and normalize the Python exception. */
	165	PyErr_Fetch(&py_exc_type, &py_exc_value, &py_exc_tb);
	166	PyErr_NormalizeException(&py_exc_type, &py_exc_value, &py_exc_tb);
	167	BT_ASSERT(py_exc_type);
	168	BT_ASSERT(py_exc_value);
	169	BT_ASSERT(py_exc_tb);
	170
	171	/*
	172	* Set the exception's traceback so it's possible to get it using
	173	* PyException_GetTraceback in
	174	* restore_current_thread_error_and_append_exception_chain_recursive.
	175	*/
	176	PyException_SetTraceback(py_exc_value, py_exc_tb);
	177
	178	restore_current_thread_error_and_append_exception_chain_recursive(
	179	active_log_level, py_exc_value, self_component_class,
	180	self_component, self_message_iterator, module_name);
	181
	182	PyErr_Restore(py_exc_type, py_exc_value, py_exc_tb);
	183	}
	184
185	static inline
84e438af SM	186	void log_exception_and_maybe_append_cause(
	187	int func_log_level,
	188	int active_log_level,
	189	bool append_error,
612a9870 PP	190	bt_self_component_class *self_component_class,
	191	bt_self_component *self_component,
	192	bt_self_message_iterator *self_message_iterator,
	193	const char *module_name)
	194	{
	195	GString *gstr;
	196
	197	BT_ASSERT(PyErr_Occurred());
	198	gstr = bt_py_common_format_current_exception(active_log_level);
	199	if (!gstr) {
	200	/* bt_py_common_format_current_exception() logs errors */
	201	goto end;
	202	}
	203
	204	BT_COMP_LOG_CUR_LVL(func_log_level, active_log_level, self_component,
	205	"%s", gstr->str);
	206
	207	if (append_error) {
	208	restore_bt_error_and_append_current_exception_chain(
	209	active_log_level, self_component_class, self_component,
	210	self_message_iterator, module_name);
	211
	212	}
	213
	214	end:
	215	if (gstr) {
	216	g_string_free(gstr, TRUE);
	217	}
	218	}
	219
	220	static
	221	bt_logging_level get_self_component_log_level(bt_self_component *self_comp)
	222	{
	223	return bt_component_get_logging_level(
	224	bt_self_component_as_component(self_comp));
	225	}
	226
	227	static
	228	bt_logging_level get_self_message_iterator_log_level(
	229	bt_self_message_iterator *self_msg_iter)
	230	{
	231	bt_self_component *self_comp =
	232	bt_self_message_iterator_borrow_component(self_msg_iter);
	233
	234	return get_self_component_log_level(self_comp);
	235	}
	236
	237	static inline
981f33dd	238	void loge_exception_append_cause_clear(const char *module_name, int active_log_level)
612a9870	239	{
84e438af	240	log_exception_and_maybe_append_cause(BT_LOG_ERROR, active_log_level,
612a9870	241	true, NULL, NULL, NULL, module_name);
981f33dd	242	PyErr_Clear();
612a9870 PP	243	}
612a9870 PP	244
612a9870	245	static inline
981f33dd	246	void logw_exception_clear(int active_log_level)
612a9870	247	{
84e438af	248	log_exception_and_maybe_append_cause(BT_LOG_WARNING, active_log_level,
612a9870	249	false, NULL, NULL, NULL, NULL);
981f33dd	250	PyErr_Clear();
612a9870	251	}