#include "Python.h"

#include "frameobject.h"

#define MODULE_NAME "_warnings"

#define DEFAULT_ACTION_NAME "default_action"

PyDoc_STRVAR(warnings__doc__,

MODULE_NAME " provides basic warning filtering support.\n"

"It is a helper module to speed up interpreter start-up.");

/* Both 'filters' and 'onceregistry' can be set in warnings.py;

get_warnings_attr() will reset these variables accordingly. */

static PyObject *_filters; /* List */

static PyObject *_once_registry; /* Dict */

static int

check_matched(PyObject *obj, PyObject *arg)

{

PyObject *result;

int rc;

if (obj == Py_None)

return 1;

result = PyObject_CallMethod(obj, "match", "O", arg);

if (result == NULL)

return -1;

rc = PyObject_IsTrue(result);

Py_DECREF(result);

return rc;

}

/*

Returns a new reference.

A NULL return value can mean false or an error.

*/

static PyObject *

get_warnings_attr(const char *attr)

{

static PyObject *warnings_str = NULL;

PyObject *all_modules;

PyObject *warnings_module;

int result;

if (warnings_str == NULL) {

warnings_str = PyUnicode_InternFromString("warnings");

if (warnings_str == NULL)

return NULL;

}

all_modules = PyImport_GetModuleDict();

result = PyDict_Contains(all_modules, warnings_str);

if (result == -1 || result == 0)

return NULL;

warnings_module = PyDict_GetItem(all_modules, warnings_str);

if (!PyObject_HasAttrString(warnings_module, attr))

return NULL;

return PyObject_GetAttrString(warnings_module, attr);

}

static PyObject *

get_once_registry(void)

{

PyObject *registry;

registry = get_warnings_attr("onceregistry");

if (registry == NULL) {

if (PyErr_Occurred())

return NULL;

return _once_registry;

}

Py_DECREF(_once_registry);

_once_registry = registry;

return registry;

}

/* The item is a borrowed reference. */

static const char *

get_filter(PyObject *category, PyObject *text, Py_ssize_t lineno,

PyObject *module, PyObject **item)

{

PyObject *action, *m, *d;

Py_ssize_t i;

PyObject *warnings_filters;

warnings_filters = get_warnings_attr("filters");

if (warnings_filters == NULL) {

if (PyErr_Occurred())

return NULL;

}

else {

Py_DECREF(_filters);

_filters = warnings_filters;

}

if (!PyList_Check(_filters)) {

PyErr_SetString(PyExc_ValueError,

MODULE_NAME ".filters must be a list");

return NULL;

}

/* _filters could change while we are iterating over it. */

for (i = 0; i < PyList_GET_SIZE(_filters); i++) {

PyObject *tmp_item, *action, *msg, *cat, *mod, *ln_obj;

Py_ssize_t ln;

int is_subclass, good_msg, good_mod;

tmp_item = *item = PyList_GET_ITEM(_filters, i);

if (PyTuple_Size(tmp_item) != 5) {

PyErr_Format(PyExc_ValueError,

MODULE_NAME ".filters item %zd isn't a 5-tuple", i);

return NULL;

}

/* Python code: action, msg, cat, mod, ln = item */

action = PyTuple_GET_ITEM(tmp_item, 0);

msg = PyTuple_GET_ITEM(tmp_item, 1);

cat = PyTuple_GET_ITEM(tmp_item, 2);

mod = PyTuple_GET_ITEM(tmp_item, 3);

ln_obj = PyTuple_GET_ITEM(tmp_item, 4);

good_msg = check_matched(msg, text);

good_mod = check_matched(mod, module);

is_subclass = PyObject_IsSubclass(category, cat);

ln = PyLong_AsSsize_t(ln_obj);

if (good_msg == -1 || good_mod == -1 || is_subclass == -1 ||

(ln == -1 && PyErr_Occurred()))

return NULL;

if (good_msg && is_subclass && good_mod && (ln == 0 || lineno == ln))

return _PyUnicode_AsString(action);

}

m = PyImport_ImportModule(MODULE_NAME);

if (m == NULL)

return NULL;

d = PyModule_GetDict(m);

Py_DECREF(m);

if (d == NULL)

return NULL;

action = PyDict_GetItemString(d, DEFAULT_ACTION_NAME);

if (action != NULL)

return _PyUnicode_AsString(action);

PyErr_SetString(PyExc_ValueError,

MODULE_NAME "." DEFAULT_ACTION_NAME " not found");

return NULL;

}

static int

already_warned(PyObject *registry, PyObject *key, int should_set)

{

PyObject *already_warned;

if (key == NULL)

return -1;

already_warned = PyDict_GetItem(registry, key);

if (already_warned != NULL) {

int rc = PyObject_IsTrue(already_warned);

if (rc != 0)

return rc;

}

/* This warning wasn't found in the registry, set it. */

if (should_set)

return PyDict_SetItem(registry, key, Py_True);

return 0;

}

/* New reference. */

static PyObject *

normalize_module(PyObject *filename)

{

PyObject *module;

const char *mod_str;

Py_ssize_t len;

int rc = PyObject_IsTrue(filename);

if (rc == -1)

return NULL;

else if (rc == 0)

return PyUnicode_FromString("<unknown>");

mod_str = _PyUnicode_AsString(filename);

if (mod_str == NULL)

return NULL;

len = PyUnicode_GetSize(filename);

if (len < 0)

return NULL;

if (len >= 3 &&

strncmp(mod_str + (len - 3), ".py", 3) == 0) {

module = PyUnicode_FromStringAndSize(mod_str, len-3);

}

else {

module = filename;

Py_INCREF(module);

}

return module;

}

static int

update_registry(PyObject *registry, PyObject *text, PyObject *category,

int add_zero)

{

PyObject *altkey, *zero = NULL;

int rc;

if (add_zero) {

zero = PyLong_FromLong(0);

if (zero == NULL)

return -1;

altkey = PyTuple_Pack(3, text, category, zero);

}

else

altkey = PyTuple_Pack(2, text, category);

rc = already_warned(registry, altkey, 1);

Py_XDECREF(zero);

Py_XDECREF(altkey);

return rc;

}

static void

show_warning(PyObject *filename, int lineno, PyObject *text, PyObject

*category, PyObject *sourceline)

{

PyObject *f_stderr;

PyObject *name;

char lineno_str[128];

PyOS_snprintf(lineno_str, sizeof(lineno_str), ":%d: ", lineno);

name = PyObject_GetAttrString(category, "__name__");

if (name == NULL) /* XXX Can an object lack a '__name__' attribute? */

return;

f_stderr = PySys_GetObject("stderr");

if (f_stderr == NULL) {

fprintf(stderr, "lost sys.stderr\n");

Py_DECREF(name);

return;

}

/* Print "filename:lineno: category: text\n" */

PyFile_WriteObject(filename, f_stderr, Py_PRINT_RAW);

PyFile_WriteString(lineno_str, f_stderr);

PyFile_WriteObject(name, f_stderr, Py_PRINT_RAW);

PyFile_WriteString(": ", f_stderr);

PyFile_WriteObject(text, f_stderr, Py_PRINT_RAW);

PyFile_WriteString("\n", f_stderr);

Py_XDECREF(name);

/* Print " source_line\n" */

if (sourceline) {

char *source_line_str = _PyUnicode_AsString(sourceline);

if (source_line_str == NULL)

return;

while (*source_line_str == ' ' || *source_line_str == '\t' ||

*source_line_str == '\014')

source_line_str++;

PyFile_WriteString(source_line_str, f_stderr);

PyFile_WriteString("\n", f_stderr);

}

else

if (_Py_DisplaySourceLine(f_stderr, _PyUnicode_AsString(filename),

lineno, 2) < 0)

return;

PyErr_Clear();

}

static PyObject *

warn_explicit(PyObject *category, PyObject *message,

PyObject *filename, int lineno,

PyObject *module, PyObject *registry, PyObject *sourceline)

{

PyObject *key = NULL, *text = NULL, *result = NULL, *lineno_obj = NULL;

PyObject *item = Py_None;

const char *action;

int rc;

if (registry && !PyDict_Check(registry) && (registry != Py_None)) {

PyErr_SetString(PyExc_TypeError, "'registry' must be a dict");

return NULL;

}

/* Normalize module. */

if (module == NULL) {

module = normalize_module(filename);

if (module == NULL)

return NULL;

}

else

Py_INCREF(module);

/* Normalize message. */

Py_INCREF(message); /* DECREF'ed in cleanup. */

rc = PyObject_IsInstance(message, PyExc_Warning);

if (rc == -1) {

goto cleanup;

}

if (rc == 1) {

text = PyObject_Str(message);

category = (PyObject*)message->ob_type;

}

else {

text = message;

message = PyObject_CallFunction(category, "O", message);

if (message == NULL)

goto cleanup;

}

lineno_obj = PyLong_FromLong(lineno);

if (lineno_obj == NULL)

goto cleanup;

/* Create key. */

key = PyTuple_Pack(3, text, category, lineno_obj);

if (key == NULL)

goto cleanup;

if ((registry != NULL) && (registry != Py_None)) {

rc = already_warned(registry, key, 0);

if (rc == -1)

goto cleanup;

else if (rc == 1)

goto return_none;

/* Else this warning hasn't been generated before. */

}

action = get_filter(category, text, lineno, module, &item);

if (action == NULL)

goto cleanup;

if (strcmp(action, "error") == 0) {

PyErr_SetObject(category, message);

goto cleanup;

}

/* Store in the registry that we've been here, *except* when the action

is "always". */

rc = 0;

if (strcmp(action, "always") != 0) {

if (registry != NULL && registry != Py_None &&

PyDict_SetItem(registry, key, Py_True) < 0)

goto cleanup;

else if (strcmp(action, "ignore") == 0)

goto return_none;

else if (strcmp(action, "once") == 0) {

if (registry == NULL || registry == Py_None) {

registry = get_once_registry();

if (registry == NULL)

goto cleanup;

}

/* _once_registry[(text, category)] = 1 */

rc = update_registry(registry, text, category, 0);

}

else if (strcmp(action, "module") == 0) {

/* registry[(text, category, 0)] = 1 */

if (registry != NULL && registry != Py_None)

rc = update_registry(registry, text, category, 0);

}

else if (strcmp(action, "default") != 0) {

PyObject *to_str = PyObject_Str(item);

const char *err_str = "???";

if (to_str != NULL) {

err_str = _PyUnicode_AsString(to_str);

if (err_str == NULL)

goto cleanup;

}

PyErr_Format(PyExc_RuntimeError,

"Unrecognized action (%s) in warnings.filters:\n %s",

action, err_str);

Py_XDECREF(to_str);

goto cleanup;

}

}

if (rc == 1) /* Already warned for this module. */

goto return_none;

if (rc == 0) {

PyObject *show_fxn = get_warnings_attr("showwarning");

if (show_fxn == NULL) {

if (PyErr_Occurred())

goto cleanup;

show_warning(filename, lineno, text, category, sourceline);

}

else {

PyObject *res;

if (!PyMethod_Check(show_fxn) && !PyFunction_Check(show_fxn)) {

PyErr_SetString(PyExc_TypeError,

"warnings.showwarning() must be set to a "

"function or method");

Py_DECREF(show_fxn);

goto cleanup;

}

res = PyObject_CallFunctionObjArgs(show_fxn, message, category,

filename, lineno_obj,

NULL);

Py_DECREF(show_fxn);

Py_XDECREF(res);

if (res == NULL)

goto cleanup;

}

}

else /* if (rc == -1) */

goto cleanup;

return_none:

result = Py_None;

Py_INCREF(result);

cleanup:

Py_XDECREF(key);

Py_XDECREF(text);

Py_XDECREF(lineno_obj);

Py_DECREF(module);

Py_XDECREF(message);

return result; /* Py_None or NULL. */

}

/* filename, module, and registry are new refs, globals is borrowed */

/* Returns 0 on error (no new refs), 1 on success */

static int

setup_context(Py_ssize_t stack_level, PyObject **filename, int *lineno,

PyObject **module, PyObject **registry)

{

PyObject *globals;

/* Setup globals and lineno. */

PyFrameObject *f = PyThreadState_GET()->frame;

while (--stack_level > 0 && f != NULL)

f = f->f_back;

if (f == NULL) {

globals = PyThreadState_Get()->interp->sysdict;

*lineno = 1;

}

else {

globals = f->f_globals;

*lineno = PyCode_Addr2Line(f->f_code, f->f_lasti);

}

*module = NULL;

/* Setup registry. */

assert(globals != NULL);

assert(PyDict_Check(globals));

*registry = PyDict_GetItemString(globals, "__warningregistry__");

if (*registry == NULL) {

int rc;

*registry = PyDict_New();

if (*registry == NULL)

return 0;

rc = PyDict_SetItemString(globals, "__warningregistry__", *registry);

if (rc < 0)

goto handle_error;

}

else

Py_INCREF(*registry);

/* Setup module. */

*module = PyDict_GetItemString(globals, "__name__");

if (*module == NULL) {

*module = PyUnicode_FromString("<string>");

if (*module == NULL)

goto handle_error;

}

else

Py_INCREF(*module);

/* Setup filename. */

*filename = PyDict_GetItemString(globals, "__file__");

if (*filename != NULL) {

Py_ssize_t len = PyUnicode_GetSize(*filename);

const char *file_str = _PyUnicode_AsString(*filename);

if (file_str == NULL || (len < 0 && PyErr_Occurred()))

goto handle_error;

/* if filename.lower().endswith((".pyc", ".pyo")): */

if (len >= 4 &&

file_str[len-4] == '.' &&

tolower(file_str[len-3]) == 'p' &&

tolower(file_str[len-2]) == 'y' &&

(tolower(file_str[len-1]) == 'c' ||

tolower(file_str[len-1]) == 'o'))

{

*filename = PyUnicode_FromStringAndSize(file_str, len-1);

if (*filename == NULL)

goto handle_error;

}

else

Py_INCREF(*filename);

}

else {

const char *module_str = _PyUnicode_AsString(*module);

if (module_str == NULL)

goto handle_error;

if (strcmp(module_str, "__main__") == 0) {

PyObject *argv = PySys_GetObject("argv");

if (argv != NULL && PyList_Size(argv) > 0) {

int is_true;

*filename = PyList_GetItem(argv, 0);

Py_INCREF(*filename);

/* If sys.argv[0] is false, then use '__main__'. */

is_true = PyObject_IsTrue(*filename);

if (is_true < 0) {

Py_DECREF(*filename);

goto handle_error;

}

else if (!is_true) {

Py_DECREF(*filename);

*filename = PyUnicode_FromString("__main__");

if (*filename == NULL)

goto handle_error;

}

}

else {

/* embedded interpreters don't have sys.argv, see bug #839151 */

*filename = PyUnicode_FromString("__main__");

if (*filename == NULL)

goto handle_error;

}

}

if (*filename == NULL) {

*filename = *module;

Py_INCREF(*filename);

}

}

return 1;

handle_error:

/* filename not XDECREF'ed here as there is no way to jump here with a

dangling reference. */

Py_XDECREF(*registry);

Py_XDECREF(*module);

return 0;

}

static PyObject *

get_category(PyObject *message, PyObject *category)

{

int rc;

/* Get category. */

rc = PyObject_IsInstance(message, PyExc_Warning);

if (rc == -1)

return NULL;

if (rc == 1)

category = (PyObject*)message->ob_type;

else if (category == NULL)

category = PyExc_UserWarning;

/* Validate category. */

rc = PyObject_IsSubclass(category, PyExc_Warning);

if (rc == -1)

return NULL;

if (rc == 0) {

PyErr_SetString(PyExc_ValueError,

"category is not a subclass of Warning");

return NULL;

}

return category;

}

static PyObject *

do_warn(PyObject *message, PyObject *category, Py_ssize_t stack_level)

{

PyObject *filename, *module, *registry, *res;

int lineno;

if (!setup_context(stack_level, &filename, &lineno, &module, &registry))

return NULL;

res = warn_explicit(category, message, filename, lineno, module, registry,

NULL);

Py_DECREF(filename);

Py_DECREF(registry);

Py_DECREF(module);

return res;

}

static PyObject *

warnings_warn(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kw_list[] = { "message", "category", "stacklevel", 0 };

PyObject *message, *category = NULL;

Py_ssize_t stack_level = 1;

if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|On:warn", kw_list,

&message, &category, &stack_level))

return NULL;

category = get_category(message, category);

if (category == NULL)

return NULL;

return do_warn(message, category, stack_level);

}

static PyObject *

warnings_warn_explicit(PyObject *self, PyObject *args, PyObject *kwds)

{

static char *kwd_list[] = {"message", "category", "filename", "lineno",

"module", "registry", "module_globals", 0};

PyObject *message;

PyObject *category;

PyObject *filename;

int lineno;

PyObject *module = NULL;

PyObject *registry = NULL;

PyObject *module_globals = NULL;

if (!PyArg_ParseTupleAndKeywords(args, kwds, "OOOi|OOO:warn_explicit",

kwd_list, &message, &category, &filename, &lineno, &module,

&registry, &module_globals))

return NULL;

if (module_globals) {

static PyObject *get_source_name = NULL;

static PyObject *splitlines_name = NULL;

PyObject *loader;

PyObject *module_name;

PyObject *source;

PyObject *source_list;

PyObject *source_line;

PyObject *returned;

if (get_source_name == NULL) {

get_source_name = PyUnicode_InternFromString("get_source");

if (!get_source_name)

return NULL;

}

if (splitlines_name == NULL) {

splitlines_name = PyUnicode_InternFromString("splitlines");

if (!splitlines_name)

return NULL;

}

/* Check/get the requisite pieces needed for the loader. */

loader = PyDict_GetItemString(module_globals, "__loader__");

module_name = PyDict_GetItemString(module_globals, "__name__");

if (loader == NULL || module_name == NULL)

goto standard_call;

/* Make sure the loader implements the optional get_source() method. */

if (!PyObject_HasAttrString(loader, "get_source"))

goto standard_call;

/* Call get_source() to get the source code. */

source = PyObject_CallMethodObjArgs(loader, get_source_name,

module_name, NULL);

if (!source)

return NULL;

else if (source == Py_None) {

Py_DECREF(Py_None);

goto standard_call;

}

/* Split the source into lines. */

source_list = PyObject_CallMethodObjArgs(source, splitlines_name,

NULL);

Py_DECREF(source);

if (!source_list)

return NULL;

/* Get the source line. */

source_line = PyList_GetItem(source_list, lineno-1);

if (!source_line) {

Py_DECREF(source_list);

return NULL;

}

/* Handle the warning. */

returned = warn_explicit(category, message, filename, lineno, module,

registry, source_line);

Py_DECREF(source_list);

return returned;

}

standard_call:

return warn_explicit(category, message, filename, lineno, module,

registry, NULL);

}

/* Function to issue a warning message; may raise an exception. */

int

PyErr_WarnEx(PyObject *category, const char *text, Py_ssize_t stack_level)

{

PyObject *res;

PyObject *message = PyUnicode_FromString(text);

if (message == NULL)

return -1;

if (category == NULL)

category = PyExc_RuntimeWarning;

res = do_warn(message, category, stack_level);

Py_DECREF(message);

if (res == NULL)

return -1;

Py_DECREF(res);

return 0;

}

/* PyErr_Warn is only for backwards compatability and will be removed.

Use PyErr_WarnEx instead. */

#undef PyErr_Warn

PyAPI_FUNC(int)

PyErr_Warn(PyObject *category, char *text)

{

return PyErr_WarnEx(category, text, 1);

}

/* Warning with explicit origin */

int

PyErr_WarnExplicit(PyObject *category, const char *text,

const char *filename_str, int lineno,

const char *module_str, PyObject *registry)

{

PyObject *res;

PyObject *message = PyUnicode_FromString(text);

PyObject *filename = PyUnicode_FromString(filename_str);

PyObject *module = NULL;

int ret = -1;

if (message == NULL || filename == NULL)

goto exit;

if (module_str != NULL) {

module = PyUnicode_FromString(module_str);

if (module == NULL)

goto exit;

}

if (category == NULL)

category = PyExc_RuntimeWarning;

res = warn_explicit(category, message, filename, lineno, module, registry,

NULL);

if (res == NULL)

goto exit;

Py_DECREF(res);

ret = 0;

exit:

Py_XDECREF(message);

Py_XDECREF(module);

Py_XDECREF(filename);

return ret;

}

PyDoc_STRVAR(warn_doc,

"Issue a warning, or maybe ignore it or raise an exception.");

PyDoc_STRVAR(warn_explicit_doc,

"Low-level inferface to warnings functionality.");

static PyMethodDef warnings_functions[] = {

{"warn", (PyCFunction)warnings_warn, METH_VARARGS | METH_KEYWORDS,

warn_doc},

{"warn_explicit", (PyCFunction)warnings_warn_explicit,

METH_VARARGS | METH_KEYWORDS, warn_explicit_doc},

/* XXX(brett.cannon): add showwarning? */

/* XXX(brett.cannon): Reasonable to add formatwarning? */

{NULL, NULL} /* sentinel */

};

static PyObject *

create_filter(PyObject *category, const char *action)

{

static PyObject *ignore_str = NULL;

static PyObject *error_str = NULL;

static PyObject *default_str = NULL;

PyObject *action_obj = NULL;

PyObject *lineno, *result;

if (!strcmp(action, "ignore")) {

if (ignore_str == NULL) {

ignore_str = PyUnicode_InternFromString("ignore");

if (ignore_str == NULL)

return NULL;

}

action_obj = ignore_str;

}

else if (!strcmp(action, "error")) {

if (error_str == NULL) {

error_str = PyUnicode_InternFromString("error");

if (error_str == NULL)

return NULL;

}

action_obj = error_str;

}

else if (!strcmp(action, "default")) {

if (default_str == NULL) {

default_str = PyUnicode_InternFromString("default");

if (default_str == NULL)

return NULL;

}

action_obj = default_str;

}

else {

Py_FatalError("unknown action");

}

/* This assumes the line number is zero for now. */

lineno = PyLong_FromLong(0);

if (lineno == NULL)

return NULL;

result = PyTuple_Pack(5, action_obj, Py_None, category, Py_None, lineno);

Py_DECREF(lineno);

return result;

}

static PyObject *

init_filters(void)

{

PyObject *filters = PyList_New(3);

const char *bytes_action;

if (filters == NULL)

return NULL;

PyList_SET_ITEM(filters, 0,

create_filter(PyExc_PendingDeprecationWarning, "ignore"));

PyList_SET_ITEM(filters, 1, create_filter(PyExc_ImportWarning, "ignore"));

if (Py_BytesWarningFlag > 1)

bytes_action = "error";

else if (Py_BytesWarningFlag)

bytes_action = "default";

else

bytes_action = "ignore";

PyList_SET_ITEM(filters, 2, create_filter(PyExc_BytesWarning,

bytes_action));

if (PyList_GET_ITEM(filters, 0) == NULL ||

PyList_GET_ITEM(filters, 1) == NULL ||

PyList_GET_ITEM(filters, 2) == NULL) {

Py_DECREF(filters);

return NULL;

}

return filters;

}

static struct PyModuleDef warningsmodule = {

PyModuleDef_HEAD_INIT,

MODULE_NAME,

warnings__doc__,

0,

warnings_functions,

NULL,

NULL,

NULL,

NULL

};

PyMODINIT_FUNC

_PyWarnings_Init(void)

{

PyObject *m, *default_action;

m = PyModule_Create(&warningsmodule);

if (m == NULL)

return NULL;

_filters = init_filters();

if (_filters == NULL)

return NULL;

Py_INCREF(_filters);

if (PyModule_AddObject(m, "filters", _filters) < 0)

return NULL;

_once_registry = PyDict_New();

if (_once_registry == NULL)

return NULL;

Py_INCREF(_once_registry);

if (PyModule_AddObject(m, "once_registry", _once_registry) < 0)

return NULL;

default_action = PyUnicode_InternFromString("default");

if (default_action == NULL)

return NULL;

if (PyModule_AddObject(m, DEFAULT_ACTION_NAME, default_action) < 0)

return NULL;

return m;

}