Library import 16 (#2433)

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1 files changed, 686 insertions, 0 deletions

diff --git a/contrib/tools/python3/Objects/structseq.c b/contrib/tools/python3/Objects/structseq.c
new file mode 100644
index 0000000000..8b18959571
--- /dev/null
+++ b/contrib/tools/python3/Objects/structseq.c
@@ -0,0 +1,686 @@
+/* Implementation helper: a struct that looks like a tuple.
+   See timemodule and posixmodule for example uses.
+
+   The structseq helper is considered an internal CPython implementation
+   detail.  Docs for modules using structseqs should call them
+   "named tuples" (be sure to include a space between the two
+   words and add a link back to the term in Docs/glossary.rst).
+*/
+
+#include "Python.h"
+#include "pycore_tuple.h"         // _PyTuple_FromArray()
+#include "pycore_object.h"        // _PyObject_GC_TRACK()
+#include "structmember.h"         // PyMemberDef
+#include "pycore_structseq.h"     // PyStructSequence_InitType()
+#include "pycore_initconfig.h"    // _PyStatus_OK()
+
+static const char visible_length_key[] = "n_sequence_fields";
+static const char real_length_key[] = "n_fields";
+static const char unnamed_fields_key[] = "n_unnamed_fields";
+static const char match_args_key[] = "__match_args__";
+
+/* Fields with this name have only a field index, not a field name.
+   They are only allowed for indices < n_visible_fields. */
+const char * const PyStructSequence_UnnamedField = "unnamed field";
+
+static Py_ssize_t
+get_type_attr_as_size(PyTypeObject *tp, PyObject *name)
+{
+    PyObject *v = PyDict_GetItemWithError(_PyType_GetDict(tp), name);
+    if (v == NULL && !PyErr_Occurred()) {
+        PyErr_Format(PyExc_TypeError,
+                     "Missed attribute '%U' of type %s",
+                     name, tp->tp_name);
+        return -1;
+    }
+    return PyLong_AsSsize_t(v);
+}
+
+#define VISIBLE_SIZE(op) Py_SIZE(op)
+#define VISIBLE_SIZE_TP(tp) \
+    get_type_attr_as_size(tp, &_Py_ID(n_sequence_fields))
+#define REAL_SIZE_TP(tp) \
+    get_type_attr_as_size(tp, &_Py_ID(n_fields))
+#define REAL_SIZE(op) REAL_SIZE_TP(Py_TYPE(op))
+
+#define UNNAMED_FIELDS_TP(tp) \
+    get_type_attr_as_size(tp, &_Py_ID(n_unnamed_fields))
+#define UNNAMED_FIELDS(op) UNNAMED_FIELDS_TP(Py_TYPE(op))
+
+
+PyObject *
+PyStructSequence_New(PyTypeObject *type)
+{
+    PyStructSequence *obj;
+    Py_ssize_t size = REAL_SIZE_TP(type), i;
+    if (size < 0) {
+        return NULL;
+    }
+    Py_ssize_t vsize = VISIBLE_SIZE_TP(type);
+    if (vsize < 0) {
+        return NULL;
+    }
+
+    obj = PyObject_GC_NewVar(PyStructSequence, type, size);
+    if (obj == NULL)
+        return NULL;
+    /* Hack the size of the variable object, so invisible fields don't appear
+     to Python code. */
+    Py_SET_SIZE(obj, vsize);
+    for (i = 0; i < size; i++)
+        obj->ob_item[i] = NULL;
+
+    return (PyObject*)obj;
+}
+
+void
+PyStructSequence_SetItem(PyObject* op, Py_ssize_t i, PyObject* v)
+{
+    PyStructSequence_SET_ITEM(op, i, v);
+}
+
+PyObject*
+PyStructSequence_GetItem(PyObject* op, Py_ssize_t i)
+{
+    return PyStructSequence_GET_ITEM(op, i);
+}
+
+
+static int
+structseq_traverse(PyStructSequence *obj, visitproc visit, void *arg)
+{
+    if (Py_TYPE(obj)->tp_flags & Py_TPFLAGS_HEAPTYPE) {
+        Py_VISIT(Py_TYPE(obj));
+    }
+    Py_ssize_t i, size;
+    size = REAL_SIZE(obj);
+    for (i = 0; i < size; ++i) {
+        Py_VISIT(obj->ob_item[i]);
+    }
+    return 0;
+}
+
+static void
+structseq_dealloc(PyStructSequence *obj)
+{
+    Py_ssize_t i, size;
+    PyObject_GC_UnTrack(obj);
+
+    PyTypeObject *tp = Py_TYPE(obj);
+    size = REAL_SIZE(obj);
+    for (i = 0; i < size; ++i) {
+        Py_XDECREF(obj->ob_item[i]);
+    }
+    PyObject_GC_Del(obj);
+    if (_PyType_HasFeature(tp, Py_TPFLAGS_HEAPTYPE)) {
+        Py_DECREF(tp);
+    }
+}
+
+/*[clinic input]
+class structseq "PyStructSequence *" "NULL"
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=9d781c6922c77752]*/
+
+#include "clinic/structseq.c.h"
+
+/*[clinic input]
+@classmethod
+structseq.__new__ as structseq_new
+    sequence as arg: object
+    dict: object(c_default="NULL") = {}
+[clinic start generated code]*/
+
+static PyObject *
+structseq_new_impl(PyTypeObject *type, PyObject *arg, PyObject *dict)
+/*[clinic end generated code: output=baa082e788b171da input=90532511101aa3fb]*/
+{
+    PyObject *ob;
+    PyStructSequence *res = NULL;
+    Py_ssize_t len, min_len, max_len, i, n_unnamed_fields;
+
+    min_len = VISIBLE_SIZE_TP(type);
+    if (min_len < 0) {
+        return NULL;
+    }
+    max_len = REAL_SIZE_TP(type);
+    if (max_len < 0) {
+        return NULL;
+    }
+    n_unnamed_fields = UNNAMED_FIELDS_TP(type);
+    if (n_unnamed_fields < 0) {
+        return NULL;
+    }
+
+    arg = PySequence_Fast(arg, "constructor requires a sequence");
+
+    if (!arg) {
+        return NULL;
+    }
+
+    if (dict && !PyDict_Check(dict)) {
+        PyErr_Format(PyExc_TypeError,
+                     "%.500s() takes a dict as second arg, if any",
+                     type->tp_name);
+        Py_DECREF(arg);
+        return NULL;
+    }
+
+    len = PySequence_Fast_GET_SIZE(arg);
+    if (min_len != max_len) {
+        if (len < min_len) {
+            PyErr_Format(PyExc_TypeError,
+                "%.500s() takes an at least %zd-sequence (%zd-sequence given)",
+                type->tp_name, min_len, len);
+            Py_DECREF(arg);
+            return NULL;
+        }
+
+        if (len > max_len) {
+            PyErr_Format(PyExc_TypeError,
+                "%.500s() takes an at most %zd-sequence (%zd-sequence given)",
+                type->tp_name, max_len, len);
+            Py_DECREF(arg);
+            return NULL;
+        }
+    }
+    else {
+        if (len != min_len) {
+            PyErr_Format(PyExc_TypeError,
+                         "%.500s() takes a %zd-sequence (%zd-sequence given)",
+                         type->tp_name, min_len, len);
+            Py_DECREF(arg);
+            return NULL;
+        }
+    }
+
+    res = (PyStructSequence*) PyStructSequence_New(type);
+    if (res == NULL) {
+        Py_DECREF(arg);
+        return NULL;
+    }
+    for (i = 0; i < len; ++i) {
+        PyObject *v = PySequence_Fast_GET_ITEM(arg, i);
+        res->ob_item[i] = Py_NewRef(v);
+    }
+    Py_DECREF(arg);
+    for (; i < max_len; ++i) {
+        if (dict == NULL) {
+            ob = Py_None;
+        }
+        else {
+            ob = _PyDict_GetItemStringWithError(dict,
+                type->tp_members[i-n_unnamed_fields].name);
+            if (ob == NULL) {
+                if (PyErr_Occurred()) {
+                    Py_DECREF(res);
+                    return NULL;
+                }
+                ob = Py_None;
+            }
+        }
+        res->ob_item[i] = Py_NewRef(ob);
+    }
+
+    _PyObject_GC_TRACK(res);
+    return (PyObject*) res;
+}
+
+
+static PyObject *
+structseq_repr(PyStructSequence *obj)
+{
+    PyTypeObject *typ = Py_TYPE(obj);
+    _PyUnicodeWriter writer;
+
+    /* Write "typename(" */
+    PyObject *type_name = PyUnicode_DecodeUTF8(typ->tp_name,
+                                               strlen(typ->tp_name),
+                                               NULL);
+    if (type_name == NULL) {
+        return NULL;
+    }
+
+    _PyUnicodeWriter_Init(&writer);
+    writer.overallocate = 1;
+    /* count 5 characters per item: "x=1, " */
+    writer.min_length = (PyUnicode_GET_LENGTH(type_name) + 1
+                         + VISIBLE_SIZE(obj) * 5 + 1);
+
+    if (_PyUnicodeWriter_WriteStr(&writer, type_name) < 0) {
+        Py_DECREF(type_name);
+        goto error;
+    }
+    Py_DECREF(type_name);
+
+    if (_PyUnicodeWriter_WriteChar(&writer, '(') < 0) {
+        goto error;
+    }
+
+    for (Py_ssize_t i=0; i < VISIBLE_SIZE(obj); i++) {
+        if (i > 0) {
+            /* Write ", " */
+            if (_PyUnicodeWriter_WriteASCIIString(&writer, ", ", 2) < 0) {
+                goto error;
+            }
+        }
+
+        /* Write "name=repr" */
+        const char *name_utf8 = typ->tp_members[i].name;
+        if (name_utf8 == NULL) {
+            PyErr_Format(PyExc_SystemError, "In structseq_repr(), member %zd name is NULL"
+                         " for type %.500s", i, typ->tp_name);
+            goto error;
+        }
+
+        PyObject *name = PyUnicode_DecodeUTF8(name_utf8, strlen(name_utf8), NULL);
+        if (name == NULL) {
+            goto error;
+        }
+        if (_PyUnicodeWriter_WriteStr(&writer, name) < 0) {
+            Py_DECREF(name);
+            goto error;
+        }
+        Py_DECREF(name);
+
+        if (_PyUnicodeWriter_WriteChar(&writer, '=') < 0) {
+            goto error;
+        }
+
+        PyObject *value = PyStructSequence_GET_ITEM(obj, i);
+        assert(value != NULL);
+        PyObject *repr = PyObject_Repr(value);
+        if (repr == NULL) {
+            goto error;
+        }
+        if (_PyUnicodeWriter_WriteStr(&writer, repr) < 0) {
+            Py_DECREF(repr);
+            goto error;
+        }
+        Py_DECREF(repr);
+    }
+
+    if (_PyUnicodeWriter_WriteChar(&writer, ')') < 0) {
+        goto error;
+    }
+
+    return _PyUnicodeWriter_Finish(&writer);
+
+error:
+    _PyUnicodeWriter_Dealloc(&writer);
+    return NULL;
+}
+
+
+static PyObject *
+structseq_reduce(PyStructSequence* self, PyObject *Py_UNUSED(ignored))
+{
+    PyObject* tup = NULL;
+    PyObject* dict = NULL;
+    PyObject* result;
+    Py_ssize_t n_fields, n_visible_fields, n_unnamed_fields, i;
+
+    n_fields = REAL_SIZE(self);
+    if (n_fields < 0) {
+        return NULL;
+    }
+    n_visible_fields = VISIBLE_SIZE(self);
+    n_unnamed_fields = UNNAMED_FIELDS(self);
+    if (n_unnamed_fields < 0) {
+        return NULL;
+    }
+    tup = _PyTuple_FromArray(self->ob_item, n_visible_fields);
+    if (!tup)
+        goto error;
+
+    dict = PyDict_New();
+    if (!dict)
+        goto error;
+
+    for (i = n_visible_fields; i < n_fields; i++) {
+        const char *n = Py_TYPE(self)->tp_members[i-n_unnamed_fields].name;
+        if (PyDict_SetItemString(dict, n, self->ob_item[i]) < 0)
+            goto error;
+    }
+
+    result = Py_BuildValue("(O(OO))", Py_TYPE(self), tup, dict);
+
+    Py_DECREF(tup);
+    Py_DECREF(dict);
+
+    return result;
+
+error:
+    Py_XDECREF(tup);
+    Py_XDECREF(dict);
+    return NULL;
+}
+
+static PyMethodDef structseq_methods[] = {
+    {"__reduce__", (PyCFunction)structseq_reduce, METH_NOARGS, NULL},
+    {NULL, NULL}
+};
+
+static Py_ssize_t
+count_members(PyStructSequence_Desc *desc, Py_ssize_t *n_unnamed_members) {
+    Py_ssize_t i;
+
+    *n_unnamed_members = 0;
+    for (i = 0; desc->fields[i].name != NULL; ++i) {
+        if (desc->fields[i].name == PyStructSequence_UnnamedField) {
+            (*n_unnamed_members)++;
+        }
+    }
+    return i;
+}
+
+static int
+initialize_structseq_dict(PyStructSequence_Desc *desc, PyObject* dict,
+                          Py_ssize_t n_members, Py_ssize_t n_unnamed_members) {
+    PyObject *v;
+
+#define SET_DICT_FROM_SIZE(key, value)                                         \
+    do {                                                                       \
+        v = PyLong_FromSsize_t(value);                                         \
+        if (v == NULL) {                                                       \
+            return -1;                                                         \
+        }                                                                      \
+        if (PyDict_SetItemString(dict, key, v) < 0) {                          \
+            Py_DECREF(v);                                                      \
+            return -1;                                                         \
+        }                                                                      \
+        Py_DECREF(v);                                                          \
+    } while (0)
+
+    SET_DICT_FROM_SIZE(visible_length_key, desc->n_in_sequence);
+    SET_DICT_FROM_SIZE(real_length_key, n_members);
+    SET_DICT_FROM_SIZE(unnamed_fields_key, n_unnamed_members);
+
+    // Prepare and set __match_args__
+    Py_ssize_t i, k;
+    PyObject* keys = PyTuple_New(desc->n_in_sequence);
+    if (keys == NULL) {
+        return -1;
+    }
+
+    for (i = k = 0; i < desc->n_in_sequence; ++i) {
+        if (desc->fields[i].name == PyStructSequence_UnnamedField) {
+            continue;
+        }
+        PyObject* new_member = PyUnicode_FromString(desc->fields[i].name);
+        if (new_member == NULL) {
+            goto error;
+        }
+        PyTuple_SET_ITEM(keys, k, new_member);
+        k++;
+    }
+
+    if (_PyTuple_Resize(&keys, k) == -1) {
+        goto error;
+    }
+
+    if (PyDict_SetItemString(dict, match_args_key, keys) < 0) {
+        goto error;
+    }
+
+    Py_DECREF(keys);
+    return 0;
+
+error:
+    Py_DECREF(keys);
+    return -1;
+}
+
+static PyMemberDef *
+initialize_members(PyStructSequence_Desc *desc,
+                   Py_ssize_t n_members, Py_ssize_t n_unnamed_members)
+{
+    PyMemberDef *members;
+
+    members = PyMem_NEW(PyMemberDef, n_members - n_unnamed_members + 1);
+    if (members == NULL) {
+        PyErr_NoMemory();
+        return NULL;
+    }
+
+    Py_ssize_t i, k;
+    for (i = k = 0; i < n_members; ++i) {
+        if (desc->fields[i].name == PyStructSequence_UnnamedField) {
+            continue;
+        }
+
+        /* The names and docstrings in these MemberDefs are statically */
+        /* allocated so it is expected that they'll outlive the MemberDef */
+        members[k].name = desc->fields[i].name;
+        members[k].type = T_OBJECT;
+        members[k].offset = offsetof(PyStructSequence, ob_item)
+          + i * sizeof(PyObject*);
+        members[k].flags = READONLY;
+        members[k].doc = desc->fields[i].doc;
+        k++;
+    }
+    members[k].name = NULL;
+
+    return members;
+}
+
+
+static void
+initialize_static_fields(PyTypeObject *type, PyStructSequence_Desc *desc,
+                         PyMemberDef *tp_members, unsigned long tp_flags)
+{
+    type->tp_name = desc->name;
+    type->tp_basicsize = sizeof(PyStructSequence) - sizeof(PyObject *);
+    type->tp_itemsize = sizeof(PyObject *);
+    type->tp_dealloc = (destructor)structseq_dealloc;
+    type->tp_repr = (reprfunc)structseq_repr;
+    type->tp_doc = desc->doc;
+    type->tp_base = &PyTuple_Type;
+    type->tp_methods = structseq_methods;
+    type->tp_new = structseq_new;
+    type->tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | tp_flags;
+    type->tp_traverse = (traverseproc) structseq_traverse;
+    type->tp_members = tp_members;
+}
+
+static int
+initialize_static_type(PyTypeObject *type, PyStructSequence_Desc *desc,
+                       Py_ssize_t n_members, Py_ssize_t n_unnamed_members) {
+    /* initialize_static_fields() should have been called already. */
+    if (PyType_Ready(type) < 0) {
+        return -1;
+    }
+    Py_INCREF(type);
+
+    if (initialize_structseq_dict(
+            desc, _PyType_GetDict(type), n_members, n_unnamed_members) < 0) {
+        Py_DECREF(type);
+        return -1;
+    }
+
+    return 0;
+}
+
+int
+_PyStructSequence_InitBuiltinWithFlags(PyInterpreterState *interp,
+                                       PyTypeObject *type,
+                                       PyStructSequence_Desc *desc,
+                                       unsigned long tp_flags)
+{
+    Py_ssize_t n_unnamed_members;
+    Py_ssize_t n_members = count_members(desc, &n_unnamed_members);
+    PyMemberDef *members = NULL;
+
+    if ((type->tp_flags & Py_TPFLAGS_READY) == 0) {
+        assert(type->tp_name == NULL);
+        assert(type->tp_members == NULL);
+        assert(type->tp_base == NULL);
+
+        members = initialize_members(desc, n_members, n_unnamed_members);
+        if (members == NULL) {
+            goto error;
+        }
+        initialize_static_fields(type, desc, members, tp_flags);
+
+        _Py_SetImmortal(type);
+    }
+#ifndef NDEBUG
+    else {
+        // Ensure that the type was initialized.
+        assert(type->tp_name != NULL);
+        assert(type->tp_members != NULL);
+        assert(type->tp_base == &PyTuple_Type);
+        assert((type->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN));
+        assert(_Py_IsImmortal(type));
+    }
+#endif
+
+    if (_PyStaticType_InitBuiltin(interp, type) < 0) {
+        PyErr_Format(PyExc_RuntimeError,
+                     "Can't initialize builtin type %s",
+                     desc->name);
+        goto error;
+    }
+
+    if (initialize_structseq_dict(
+            desc, _PyType_GetDict(type), n_members, n_unnamed_members) < 0)
+    {
+        goto error;
+    }
+
+    return 0;
+
+error:
+    if (members != NULL) {
+        PyMem_Free(members);
+    }
+    return -1;
+}
+
+int
+PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
+{
+    PyMemberDef *members;
+    Py_ssize_t n_members, n_unnamed_members;
+
+#ifdef Py_TRACE_REFS
+    /* if the type object was chained, unchain it first
+       before overwriting its storage */
+    if (type->ob_base.ob_base._ob_next) {
+        _Py_ForgetReference((PyObject *)type);
+    }
+#endif
+
+    /* PyTypeObject has already been initialized */
+    if (Py_REFCNT(type) != 0) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+
+    n_members = count_members(desc, &n_unnamed_members);
+    members = initialize_members(desc, n_members, n_unnamed_members);
+    if (members == NULL) {
+        return -1;
+    }
+    initialize_static_fields(type, desc, members, 0);
+    if (initialize_static_type(type, desc, n_members, n_unnamed_members) < 0) {
+        PyMem_Free(members);
+        return -1;
+    }
+    return 0;
+}
+
+void
+PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
+{
+    (void)PyStructSequence_InitType2(type, desc);
+}
+
+
+/* This is exposed in the internal API, not the public API.
+   It is only called on builtin static types, which are all
+   initialized via _PyStructSequence_InitBuiltinWithFlags(). */
+
+void
+_PyStructSequence_FiniBuiltin(PyInterpreterState *interp, PyTypeObject *type)
+{
+    // Ensure that the type is initialized
+    assert(type->tp_name != NULL);
+    assert(type->tp_base == &PyTuple_Type);
+    assert((type->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN));
+    assert(_Py_IsImmortal(type));
+
+    // Cannot delete a type if it still has subclasses
+    if (_PyType_HasSubclasses(type)) {
+        // XXX Shouldn't this be an error?
+        return;
+    }
+
+    _PyStaticType_Dealloc(interp, type);
+
+    if (_Py_IsMainInterpreter(interp)) {
+        // Undo _PyStructSequence_InitBuiltinWithFlags().
+        type->tp_name = NULL;
+        PyMem_Free(type->tp_members);
+        type->tp_members = NULL;
+        type->tp_base = NULL;
+    }
+}
+
+
+PyTypeObject *
+_PyStructSequence_NewType(PyStructSequence_Desc *desc, unsigned long tp_flags)
+{
+    PyMemberDef *members;
+    PyTypeObject *type;
+    PyType_Slot slots[8];
+    PyType_Spec spec;
+    Py_ssize_t n_members, n_unnamed_members;
+
+    /* Initialize MemberDefs */
+    n_members = count_members(desc, &n_unnamed_members);
+    members = initialize_members(desc, n_members, n_unnamed_members);
+    if (members == NULL) {
+        return NULL;
+    }
+
+    /* Initialize Slots */
+    slots[0] = (PyType_Slot){Py_tp_dealloc, (destructor)structseq_dealloc};
+    slots[1] = (PyType_Slot){Py_tp_repr, (reprfunc)structseq_repr};
+    slots[2] = (PyType_Slot){Py_tp_doc, (void *)desc->doc};
+    slots[3] = (PyType_Slot){Py_tp_methods, structseq_methods};
+    slots[4] = (PyType_Slot){Py_tp_new, structseq_new};
+    slots[5] = (PyType_Slot){Py_tp_members, members};
+    slots[6] = (PyType_Slot){Py_tp_traverse, (traverseproc)structseq_traverse};
+    slots[7] = (PyType_Slot){0, 0};
+
+    /* Initialize Spec */
+    /* The name in this PyType_Spec is statically allocated so it is */
+    /* expected that it'll outlive the PyType_Spec */
+    spec.name = desc->name;
+    spec.basicsize = sizeof(PyStructSequence) - sizeof(PyObject *);
+    spec.itemsize = sizeof(PyObject *);
+    spec.flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | tp_flags;
+    spec.slots = slots;
+
+    type = (PyTypeObject *)PyType_FromSpecWithBases(&spec, (PyObject *)&PyTuple_Type);
+    PyMem_Free(members);
+    if (type == NULL) {
+        return NULL;
+    }
+
+    if (initialize_structseq_dict(
+            desc, _PyType_GetDict(type), n_members, n_unnamed_members) < 0) {
+        Py_DECREF(type);
+        return NULL;
+    }
+
+    return type;
+}
+
+
+PyTypeObject *
+PyStructSequence_NewType(PyStructSequence_Desc *desc)
+{
+    return _PyStructSequence_NewType(desc, 0);
+}