#! /usr/bin/env python
"""Generate C code from an ASDL description."""
import sys
import textwrap
import types
from argparse import ArgumentParser
from contextlib import contextmanager
from pathlib import Path
import asdl
TABSIZE = 4
MAX_COL = 80
AUTOGEN_MESSAGE = "// File automatically generated by {}.\n\n"
builtin_type_to_c_type = {
"identifier": "PyUnicode_Type",
"string": "PyUnicode_Type",
"int": "PyLong_Type",
"constant": "PyBaseObject_Type",
}
def get_c_type(name):
"""Return a string for the C name of the type.
This function special cases the default types provided by asdl.
"""
if name in asdl.builtin_types:
return name
else:
return "%s_ty" % name
def reflow_lines(s, depth):
"""Reflow the line s indented depth tabs.
Return a sequence of lines where no line extends beyond MAX_COL
when properly indented. The first line is properly indented based
exclusively on depth * TABSIZE. All following lines -- these are
the reflowed lines generated by this function -- start at the same
column as the first character beyond the opening { in the first
line.
"""
size = MAX_COL - depth * TABSIZE
if len(s) < size:
return [s]
lines = []
cur = s
padding = ""
while len(cur) > size:
i = cur.rfind(' ', 0, size)
# XXX this should be fixed for real
if i == -1 and 'GeneratorExp' in cur:
i = size + 3
assert i != -1, "Impossible line %d to reflow: %r" % (size, s)
lines.append(padding + cur[:i])
if len(lines) == 1:
# find new size based on brace
j = cur.find('{', 0, i)
if j >= 0:
j += 2 # account for the brace and the space after it
size -= j
padding = " " * j
else:
j = cur.find('(', 0, i)
if j >= 0:
j += 1 # account for the paren (no space after it)
size -= j
padding = " " * j
cur = cur[i+1:]
else:
lines.append(padding + cur)
return lines
def reflow_c_string(s, depth):
return '"%s"' % s.replace('\n', '\\n"\n%s"' % (' ' * depth * TABSIZE))
def is_simple(sum_type):
"""Return True if a sum is a simple.
A sum is simple if its types have no fields and itself
doesn't have any attributes. Instances of these types are
cached at C level, and they act like singletons when propagating
parser generated nodes into Python level, e.g.
unaryop = Invert | Not | UAdd | USub
"""
return not (
sum_type.attributes or
any(constructor.fields for constructor in sum_type.types)
)
def asdl_of(name, obj):
if isinstance(obj, asdl.Product) or isinstance(obj, asdl.Constructor):
fields = ", ".join(map(str, obj.fields))
if fields:
fields = "({})".format(fields)
return "{}{}".format(name, fields)
else:
if is_simple(obj):
types = " | ".join(type.name for type in obj.types)
else:
sep = "\n{}| ".format(" " * (len(name) + 1))
types = sep.join(
asdl_of(type.name, type) for type in obj.types
)
return "{} = {}".format(name, types)
class EmitVisitor(asdl.VisitorBase):
"""Visit that emits lines"""
def __init__(self, file, metadata = None):
self.file = file
self._metadata = metadata
super(EmitVisitor, self).__init__()
def emit(self, s, depth, reflow=True):
# XXX reflow long lines?
if reflow:
lines = reflow_lines(s, depth)
else:
lines = [s]
for line in lines:
if line:
line = (" " * TABSIZE * depth) + line
self.file.write(line + "\n")
@property
def metadata(self):
if self._metadata is None:
raise ValueError(
"%s was expecting to be annotated with metadata"
% type(self).__name__
)
return self._metadata
@metadata.setter
def metadata(self, value):
self._metadata = value
class MetadataVisitor(asdl.VisitorBase):
ROOT_TYPE = "AST"
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
# Metadata:
# - simple_sums: Tracks the list of compound type
# names where all the constructors
# belonging to that type lack of any
# fields.
# - identifiers: All identifiers used in the AST declarations
# - singletons: List of all constructors that originates from
# simple sums.
# - types: List of all top level type names
#
self.metadata = types.SimpleNamespace(
simple_sums=set(),
identifiers=set(),
singletons=set(),
types={self.ROOT_TYPE},
)
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, type.name)
def visitSum(self, sum, name):
self.metadata.types.add(name)
simple_sum = is_simple(sum)
if simple_sum:
self.metadata.simple_sums.add(name)
for constructor in sum.types:
if simple_sum:
self.metadata.singletons.add(constructor.name)
self.visitConstructor(constructor)
self.visitFields(sum.attributes)
def visitConstructor(self, constructor):
self.metadata.types.add(constructor.name)
self.visitFields(constructor.fields)
def visitProduct(self, product, name):
self.metadata.types.add(name)
self.visitFields(product.attributes)
self.visitFields(product.fields)
def visitFields(self, fields):
for field in fields:
self.visitField(field)
def visitField(self, field):
self.metadata.identifiers.add(field.name)
class TypeDefVisitor(EmitVisitor):
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type, depth=0):
self.visit(type.value, type.name, depth)
def visitSum(self, sum, name, depth):
if is_simple(sum):
self.simple_sum(sum, name, depth)
else:
self.sum_with_constructors(sum, name, depth)
def simple_sum(self, sum, name, depth):
enum = []
for i in range(len(sum.types)):
type = sum.types[i]
enum.append("%s=%d" % (type.name, i + 1))
enums = ", ".join(enum)
ctype = get_c_type(name)
s = "typedef enum _%s { %s } %s;" % (name, enums, ctype)
self.emit(s, depth)
self.emit("", depth)
def sum_with_constructors(self, sum, name, depth):
ctype = get_c_type(name)
s = "typedef struct _%(name)s *%(ctype)s;" % locals()
self.emit(s, depth)
self.emit("", depth)
def visitProduct(self, product, name, depth):
ctype = get_c_type(name)
s = "typedef struct _%(name)s *%(ctype)s;" % locals()
self.emit(s, depth)
self.emit("", depth)
class SequenceDefVisitor(EmitVisitor):
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type, depth=0):
self.visit(type.value, type.name, depth)
def visitSum(self, sum, name, depth):
if is_simple(sum):
return
self.emit_sequence_constructor(name, depth)
def emit_sequence_constructor(self, name,depth):
ctype = get_c_type(name)
self.emit("""\
typedef struct {
_ASDL_SEQ_HEAD
%(ctype)s typed_elements[1];
} asdl_%(name)s_seq;""" % locals(), reflow=False, depth=depth)
self.emit("", depth)
self.emit("asdl_%(name)s_seq *_Py_asdl_%(name)s_seq_new(Py_ssize_t size, PyArena *arena);" % locals(), depth)
self.emit("", depth)
def visitProduct(self, product, name, depth):
self.emit_sequence_constructor(name, depth)
class StructVisitor(EmitVisitor):
"""Visitor to generate typedefs for AST."""
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type, depth=0):
self.visit(type.value, type.name, depth)
def visitSum(self, sum, name, depth):
if not is_simple(sum):
self.sum_with_constructors(sum, name, depth)
def sum_with_constructors(self, sum, name, depth):
def emit(s, depth=depth):
self.emit(s % sys._getframe(1).f_locals, depth)
enum = []
for i in range(len(sum.types)):
type = sum.types[i]
enum.append("%s_kind=%d" % (type.name, i + 1))
emit("enum _%(name)s_kind {" + ", ".join(enum) + "};")
emit("struct _%(name)s {")
emit("enum _%(name)s_kind kind;", depth + 1)
emit("union {", depth + 1)
for t in sum.types:
self.visit(t, depth + 2)
emit("} v;", depth + 1)
for field in sum.attributes:
# rudimentary attribute handling
type = str(field.type)
assert type in asdl.builtin_types, type
emit("%s %s;" % (type, field.name), depth + 1);
emit("};")
emit("")
def visitConstructor(self, cons, depth):
if cons.fields:
self.emit("struct {", depth)
for f in cons.fields:
self.visit(f, depth + 1)
self.emit("} %s;" % cons.name, depth)
self.emit("", depth)
def visitField(self, field, depth):
# XXX need to lookup field.type, because it might be something
# like a builtin...
ctype = get_c_type(field.type)
name = field.name
if field.seq:
if field.type in self.metadata.simple_sums:
self.emit("asdl_int_seq *%(name)s;" % locals(), depth)
else:
_type = field.type
self.emit("asdl_%(_type)s_seq *%(name)s;" % locals(), depth)
else:
self.emit("%(ctype)s %(name)s;" % locals(), depth)
def visitProduct(self, product, name, depth):
self.emit("struct _%(name)s {" % locals(), depth)
for f in product.fields:
self.visit(f, depth + 1)
for field in product.attributes:
# rudimentary attribute handling
type = str(field.type)
assert type in asdl.builtin_types, type
self.emit("%s %s;" % (type, field.name), depth + 1);
self.emit("};", depth)
self.emit("", depth)
def ast_func_name(name):
return f"_PyAST_{name}"
class PrototypeVisitor(EmitVisitor):
"""Generate function prototypes for the .h file"""
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, type.name)
def visitSum(self, sum, name):
if is_simple(sum):
pass # XXX
else:
for t in sum.types:
self.visit(t, name, sum.attributes)
def get_args(self, fields):
"""Return list of C argument info, one for each field.
Argument info is 3-tuple of a C type, variable name, and flag
that is true if type can be NULL.
"""
args = []
unnamed = {}
for f in fields:
if f.name is None:
name = f.type
c = unnamed[name] = unnamed.get(name, 0) + 1
if c > 1:
name = "name%d" % (c - 1)
else:
name = f.name
# XXX should extend get_c_type() to handle this
if f.seq:
if f.type in self.metadata.simple_sums:
ctype = "asdl_int_seq *"
else:
ctype = f"asdl_{f.type}_seq *"
else:
ctype = get_c_type(f.type)
args.append((ctype, name, f.opt or f.seq))
return args
def visitConstructor(self, cons, type, attrs):
args = self.get_args(cons.fields)
attrs = self.get_args(attrs)
ctype = get_c_type(type)
self.emit_function(cons.name, ctype, args, attrs)
def emit_function(self, name, ctype, args, attrs, union=True):
args = args + attrs
if args:
argstr = ", ".join(["%s %s" % (atype, aname)
for atype, aname, opt in args])
argstr += ", PyArena *arena"
else:
argstr = "PyArena *arena"
self.emit("%s %s(%s);" % (ctype, ast_func_name(name), argstr), False)
def visitProduct(self, prod, name):
self.emit_function(name, get_c_type(name),
self.get_args(prod.fields),
self.get_args(prod.attributes),
union=False)
class FunctionVisitor(PrototypeVisitor):
"""Visitor to generate constructor functions for AST."""
def emit_function(self, name, ctype, args, attrs, union=True):
def emit(s, depth=0, reflow=True):
self.emit(s, depth, reflow)
argstr = ", ".join(["%s %s" % (atype, aname)
for atype, aname, opt in args + attrs])
if argstr:
argstr += ", PyArena *arena"
else:
argstr = "PyArena *arena"
self.emit("%s" % ctype, 0)
emit("%s(%s)" % (ast_func_name(name), argstr))
emit("{")
emit("%s p;" % ctype, 1)
for argtype, argname, opt in args:
if not opt and argtype != "int":
emit("if (!%s) {" % argname, 1)
emit("PyErr_SetString(PyExc_ValueError,", 2)
msg = "field '%s' is required for %s" % (argname, name)
emit(' "%s");' % msg,
2, reflow=False)
emit('return NULL;', 2)
emit('}', 1)
emit("p = (%s)_PyArena_Malloc(arena, sizeof(*p));" % ctype, 1);
emit("if (!p)", 1)
emit("return NULL;", 2)
if union:
self.emit_body_union(name, args, attrs)
else:
self.emit_body_struct(name, args, attrs)
emit("return p;", 1)
emit("}")
emit("")
def emit_body_union(self, name, args, attrs):
def emit(s, depth=0, reflow=True):
self.emit(s, depth, reflow)
emit("p->kind = %s_kind;" % name, 1)
for argtype, argname, opt in args:
emit("p->v.%s.%s = %s;" % (name, argname, argname), 1)
for argtype, argname, opt in attrs:
emit("p->%s = %s;" % (argname, argname), 1)
def emit_body_struct(self, name, args, attrs):
def emit(s, depth=0, reflow=True):
self.emit(s, depth, reflow)
for argtype, argname, opt in args:
emit("p->%s = %s;" % (argname, argname), 1)
for argtype, argname, opt in attrs:
emit("p->%s = %s;" % (argname, argname), 1)
class PickleVisitor(EmitVisitor):
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, type.name)
def visitSum(self, sum, name):
pass
def visitProduct(self, sum, name):
pass
def visitConstructor(self, cons, name):
pass
def visitField(self, sum):
pass
class Obj2ModPrototypeVisitor(PickleVisitor):
def visitProduct(self, prod, name):
code = "static int obj2ast_%s(struct ast_state *state, PyObject* obj, %s* out, PyArena* arena);"
self.emit(code % (name, get_c_type(name)), 0)
visitSum = visitProduct
class Obj2ModVisitor(PickleVisitor):
attribute_special_defaults = {
"end_lineno": "lineno",
"end_col_offset": "col_offset",
}
@contextmanager
def recursive_call(self, node, level):
self.emit('if (_Py_EnterRecursiveCall(" while traversing \'%s\' node")) {' % node, level, reflow=False)
self.emit('goto failed;', level + 1)
self.emit('}', level)
yield
self.emit('_Py_LeaveRecursiveCall();', level)
def funcHeader(self, name):
ctype = get_c_type(name)
self.emit("int", 0)
self.emit("obj2ast_%s(struct ast_state *state, PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
self.emit("{", 0)
self.emit("int isinstance;", 1)
self.emit("", 0)
def sumTrailer(self, name, add_label=False):
self.emit("", 0)
# there's really nothing more we can do if this fails ...
error = "expected some sort of %s, but got %%R" % name
format = "PyErr_Format(PyExc_TypeError, \"%s\", obj);"
self.emit(format % error, 1, reflow=False)
if add_label:
self.emit("failed:", 1)
self.emit("Py_XDECREF(tmp);", 1)
self.emit("return -1;", 1)
self.emit("}", 0)
self.emit("", 0)
def simpleSum(self, sum, name):
self.funcHeader(name)
for t in sum.types:
line = ("isinstance = PyObject_IsInstance(obj, "
"state->%s_type);")
self.emit(line % (t.name,), 1)
self.emit("if (isinstance == -1) {", 1)
self.emit("return -1;", 2)
self.emit("}", 1)
self.emit("if (isinstance) {", 1)
self.emit("*out = %s;" % t.name, 2)
self.emit("return 0;", 2)
self.emit("}", 1)
self.sumTrailer(name)
def buildArgs(self, fields):
return ", ".join(fields + ["arena"])
def complexSum(self, sum, name):
self.funcHeader(name)
self.emit("PyObject *tmp = NULL;", 1)
self.emit("PyObject *tp;", 1)
for a in sum.attributes:
self.visitAttributeDeclaration(a, name, sum=sum)
self.emit("", 0)
# XXX: should we only do this for 'expr'?
self.emit("if (obj == Py_None) {", 1)
self.emit("*out = NULL;", 2)
self.emit("return 0;", 2)
self.emit("}", 1)
for a in sum.attributes:
self.visitField(a, name, sum=sum, depth=1)
for t in sum.types:
self.emit("tp = state->%s_type;" % (t.name,), 1)
self.emit("isinstance = PyObject_IsInstance(obj, tp);", 1)
self.emit("if (isinstance == -1) {", 1)
self.emit("return -1;", 2)
self.emit("}", 1)
self.emit("if (isinstance) {", 1)
for f in t.fields:
self.visitFieldDeclaration(f, t.name, sum=sum, depth=2)
self.emit("", 0)
for f in t.fields:
self.visitField(f, t.name, sum=sum, depth=2)
args = [f.name for f in t.fields] + [a.name for a in sum.attributes]
self.emit("*out = %s(%s);" % (ast_func_name(t.name), self.buildArgs(args)), 2)
self.emit("if (*out == NULL) goto failed;", 2)
self.emit("return 0;", 2)
self.emit("}", 1)
self.sumTrailer(name, True)
def visitAttributeDeclaration(self, a, name, sum=sum):
ctype = get_c_type(a.type)
self.emit("%s %s;" % (ctype, a.name), 1)
def visitSum(self, sum, name):
if is_simple(sum):
self.simpleSum(sum, name)
else:
self.complexSum(sum, name)
def visitProduct(self, prod, name):
ctype = get_c_type(name)
self.emit("int", 0)
self.emit("obj2ast_%s(struct ast_state *state, PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
self.emit("{", 0)
self.emit("PyObject* tmp = NULL;", 1)
for f in prod.fields:
self.visitFieldDeclaration(f, name, prod=prod, depth=1)
for a in prod.attributes:
self.visitFieldDeclaration(a, name, prod=prod, depth=1)
self.emit("", 0)
for f in prod.fields:
self.visitField(f, name, prod=prod, depth=1)
for a in prod.attributes:
self.visitField(a, name, prod=prod, depth=1)
args = [f.name for f in prod.fields]
args.extend([a.name for a in prod.attributes])
self.emit("*out = %s(%s);" % (ast_func_name(name), self.buildArgs(args)), 1)
self.emit("if (*out == NULL) goto failed;", 1)
self.emit("return 0;", 1)
self.emit("failed:", 0)
self.emit("Py_XDECREF(tmp);", 1)
self.emit("return -1;", 1)
self.emit("}", 0)
self.emit("", 0)
def visitFieldDeclaration(self, field, name, sum=None, prod=None, depth=0):
ctype = get_c_type(field.type)
if field.seq:
if self.isSimpleType(field):
self.emit("asdl_int_seq* %s;" % field.name, depth)
else:
_type = field.type
self.emit(f"asdl_{field.type}_seq* {field.name};", depth)
else:
ctype = get_c_type(field.type)
self.emit("%s %s;" % (ctype, field.name), depth)
def isNumeric(self, field):
return get_c_type(field.type) in ("int", "bool")
def isSimpleType(self, field):
return field.type in self.metadata.simple_sums or self.isNumeric(field)
def visitField(self, field, name, sum=None, prod=None, depth=0):
ctype = get_c_type(field.type)
line = "if (PyObject_GetOptionalAttr(obj, state->%s, &tmp) < 0) {"
self.emit(line % field.name, depth)
self.emit("return -1;", depth+1)
self.emit("}", depth)
if field.seq:
self.emit("if (tmp == NULL) {", depth)
self.emit("tmp = PyList_New(0);", depth+1)
self.emit("if (tmp == NULL) {", depth+1)
self.emit("return -1;", depth+2)
self.emit("}", depth+1)
self.emit("}", depth)
self.emit("{", depth)
else:
if not field.opt:
self.emit("if (tmp == NULL) {", depth)
message = "required field \\\"%s\\\" missing from %s" % (field.name, name)
format = "PyErr_SetString(PyExc_TypeError, \"%s\");"
self.emit(format % message, depth+1, reflow=False)
self.emit("return -1;", depth+1)
else:
self.emit("if (tmp == NULL || tmp == Py_None) {", depth)
self.emit("Py_CLEAR(tmp);", depth+1)
if self.isNumeric(field):
if field.name in self.attribute_special_defaults:
self.emit(
"%s = %s;" % (field.name, self.attribute_special_defaults[field.name]),
depth+1,
)
else:
self.emit("%s = 0;" % field.name, depth+1)
elif not self.isSimpleType(field):
self.emit("%s = NULL;" % field.name, depth+1)
else:
raise TypeError("could not determine the default value for %s" % field.name)
self.emit("}", depth)
self.emit("else {", depth)
self.emit("int res;", depth+1)
if field.seq:
self.emit("Py_ssize_t len;", depth+1)
self.emit("Py_ssize_t i;", depth+1)
self.emit("if (!PyList_Check(tmp)) {", depth+1)
self.emit("PyErr_Format(PyExc_TypeError, \"%s field \\\"%s\\\" must "
"be a list, not a %%.200s\", _PyType_Name(Py_TYPE(tmp)));" %
(name, field.name),
depth+2, reflow=False)
self.emit("goto failed;", depth+2)
self.emit("}", depth+1)
self.emit("len = PyList_GET_SIZE(tmp);", depth+1)
if self.isSimpleType(field):
self.emit("%s = _Py_asdl_int_seq_new(len, arena);" % field.name, depth+1)
else:
self.emit("%s = _Py_asdl_%s_seq_new(len, arena);" % (field.name, field.type), depth+1)
self.emit("if (%s == NULL) goto failed;" % field.name, depth+1)
self.emit("for (i = 0; i < len; i++) {", depth+1)
self.emit("%s val;" % ctype, depth+2)
self.emit("PyObject *tmp2 = Py_NewRef(PyList_GET_ITEM(tmp, i));", depth+2)
with self.recursive_call(name, depth+2):
self.emit("res = obj2ast_%s(state, tmp2, &val, arena);" %
field.type, depth+2, reflow=False)
self.emit("Py_DECREF(tmp2);", depth+2)
self.emit("if (res != 0) goto failed;", depth+2)
self.emit("if (len != PyList_GET_SIZE(tmp)) {", depth+2)
self.emit("PyErr_SetString(PyExc_RuntimeError, \"%s field \\\"%s\\\" "
"changed size during iteration\");" %
(name, field.name),
depth+3, reflow=False)
self.emit("goto failed;", depth+3)
self.emit("}", depth+2)
self.emit("asdl_seq_SET(%s, i, val);" % field.name, depth+2)
self.emit("}", depth+1)
else:
with self.recursive_call(name, depth+1):
self.emit("res = obj2ast_%s(state, tmp, &%s, arena);" %
(field.type, field.name), depth+1)
self.emit("if (res != 0) goto failed;", depth+1)
self.emit("Py_CLEAR(tmp);", depth+1)
self.emit("}", depth)
class SequenceConstructorVisitor(EmitVisitor):
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, type.name)
def visitProduct(self, prod, name):
self.emit_sequence_constructor(name, get_c_type(name))
def visitSum(self, sum, name):
if not is_simple(sum):
self.emit_sequence_constructor(name, get_c_type(name))
def emit_sequence_constructor(self, name, type):
self.emit(f"GENERATE_ASDL_SEQ_CONSTRUCTOR({name}, {type})", depth=0)
class PyTypesDeclareVisitor(PickleVisitor):
def visitProduct(self, prod, name):
self.emit("static PyObject* ast2obj_%s(struct ast_state *state, struct validator *vstate, void*);" % name, 0)
if prod.attributes:
self.emit("static const char * const %s_attributes[] = {" % name, 0)
for a in prod.attributes:
self.emit('"%s",' % a.name, 1)
self.emit("};", 0)
if prod.fields:
self.emit("static const char * const %s_fields[]={" % name,0)
for f in prod.fields:
self.emit('"%s",' % f.name, 1)
self.emit("};", 0)
def visitSum(self, sum, name):
if sum.attributes:
self.emit("static const char * const %s_attributes[] = {" % name, 0)
for a in sum.attributes:
self.emit('"%s",' % a.name, 1)
self.emit("};", 0)
ptype = "void*"
if is_simple(sum):
ptype = get_c_type(name)
self.emit("static PyObject* ast2obj_%s(struct ast_state *state, struct validator *vstate, %s);" % (name, ptype), 0)
for t in sum.types:
self.visitConstructor(t, name)
def visitConstructor(self, cons, name):
if cons.fields:
self.emit("static const char * const %s_fields[]={" % cons.name, 0)
for t in cons.fields:
self.emit('"%s",' % t.name, 1)
self.emit("};",0)
class AnnotationsVisitor(PickleVisitor):
def visitModule(self, mod):
self.file.write(textwrap.dedent('''
static int
add_ast_annotations(struct ast_state *state)
{
bool cond;
'''))
for dfn in mod.dfns:
self.visit(dfn)
self.file.write(textwrap.dedent('''
return 1;
}
'''))
def visitProduct(self, prod, name):
self.emit_annotations(name, prod.fields)
def visitSum(self, sum, name):
for t in sum.types:
self.visitConstructor(t, name)
def visitConstructor(self, cons, name):
self.emit_annotations(cons.name, cons.fields)
def emit_annotations(self, name, fields):
self.emit(f"PyObject *{name}_annotations = PyDict_New();", 1)
self.emit(f"if (!{name}_annotations) return 0;", 1)
for field in fields:
self.emit("{", 1)
if field.type in builtin_type_to_c_type:
self.emit(f"PyObject *type = (PyObject *)&{builtin_type_to_c_type[field.type]};", 2)
else:
self.emit(f"PyObject *type = state->{field.type}_type;", 2)
if field.opt:
self.emit("type = _Py_union_type_or(type, Py_None);", 2)
self.emit("cond = type != NULL;", 2)
self.emit_annotations_error(name, 2)
elif field.seq:
self.emit("type = Py_GenericAlias((PyObject *)&PyList_Type, type);", 2)
self.emit("cond = type != NULL;", 2)
self.emit_annotations_error(name, 2)
else:
self.emit("Py_INCREF(type);", 2)
self.emit(f"cond = PyDict_SetItemString({name}_annotations, \"{field.name}\", type) == 0;", 2)
self.emit("Py_DECREF(type);", 2)
self.emit_annotations_error(name, 2)
self.emit("}", 1)
self.emit(f'cond = PyObject_SetAttrString(state->{name}_type, "_field_types", {name}_annotations) == 0;', 1)
self.emit_annotations_error(name, 1)
self.emit(f'cond = PyObject_SetAttrString(state->{name}_type, "__annotations__", {name}_annotations) == 0;', 1)
self.emit_annotations_error(name, 1)
self.emit(f"Py_DECREF({name}_annotations);", 1)
def emit_annotations_error(self, name, depth):
self.emit("if (!cond) {", depth)
self.emit(f"Py_DECREF({name}_annotations);", depth + 1)
self.emit("return 0;", depth + 1)
self.emit("}", depth)
class PyTypesVisitor(PickleVisitor):
def visitModule(self, mod):
self.emit("""
typedef struct {
PyObject_HEAD
PyObject *dict;
} AST_object;
static void
ast_dealloc(AST_object *self)
{
/* bpo-31095: UnTrack is needed before calling any callbacks */
PyTypeObject *tp = Py_TYPE(self);
PyObject_GC_UnTrack(self);
Py_CLEAR(self->dict);
freefunc free_func = PyType_GetSlot(tp, Py_tp_free);
assert(free_func != NULL);
free_func(self);
Py_DECREF(tp);
}
static int
ast_traverse(AST_object *self, visitproc visit, void *arg)
{
Py_VISIT(Py_TYPE(self));
Py_VISIT(self->dict);
return 0;
}
static int
ast_clear(AST_object *self)
{
Py_CLEAR(self->dict);
return 0;
}
static int
ast_type_init(PyObject *self, PyObject *args, PyObject *kw)
{
struct ast_state *state = get_ast_state();
if (state == NULL) {
return -1;
}
Py_ssize_t i, numfields = 0;
int res = -1;
PyObject *key, *value, *fields, *attributes = NULL, *remaining_fields = NULL;
if (PyObject_GetOptionalAttr((PyObject*)Py_TYPE(self), state->_fields, &fields) < 0) {
goto cleanup;
}
if (fields) {
numfields = PySequence_Size(fields);
if (numfields == -1) {
goto cleanup;
}
remaining_fields = PySet_New(fields);
}
else {
remaining_fields = PySet_New(NULL);
}
if (remaining_fields == NULL) {
goto cleanup;
}
res = 0; /* if no error occurs, this stays 0 to the end */
if (numfields < PyTuple_GET_SIZE(args)) {
PyErr_Format(PyExc_TypeError, "%.400s constructor takes at most "
"%zd positional argument%s",
_PyType_Name(Py_TYPE(self)),
numfields, numfields == 1 ? "" : "s");
res = -1;
goto cleanup;
}
for (i = 0; i < PyTuple_GET_SIZE(args); i++) {
/* cannot be reached when fields is NULL */
PyObject *name = PySequence_GetItem(fields, i);
if (!name) {
res = -1;
goto cleanup;
}
res = PyObject_SetAttr(self, name, PyTuple_GET_ITEM(args, i));
if (PySet_Discard(remaining_fields, name) < 0) {
res = -1;
Py_DECREF(name);
goto cleanup;
}
Py_DECREF(name);
if (res < 0) {
goto cleanup;
}
}
if (kw) {
i = 0; /* needed by PyDict_Next */
while (PyDict_Next(kw, &i, &key, &value)) {
int contains = PySequence_Contains(fields, key);
if (contains == -1) {
res = -1;
goto cleanup;
}
else if (contains == 1) {
int p = PySet_Discard(remaining_fields, key);
if (p == -1) {
res = -1;
goto cleanup;
}
if (p == 0) {
PyErr_Format(PyExc_TypeError,
"%.400s got multiple values for argument '%U'",
Py_TYPE(self)->tp_name, key);
res = -1;
goto cleanup;
}
}
else {
// Lazily initialize "attributes"
if (attributes == NULL) {
attributes = PyObject_GetAttr((PyObject*)Py_TYPE(self), state->_attributes);
if (attributes == NULL) {
res = -1;
goto cleanup;
}
}
int contains = PySequence_Contains(attributes, key);
if (contains == -1) {
res = -1;
goto cleanup;
}
else if (contains == 0) {
if (PyErr_WarnFormat(
PyExc_DeprecationWarning, 1,
"%.400s.__init__ got an unexpected keyword argument '%U'. "
"Support for arbitrary keyword arguments is deprecated "
"and will be removed in Python 3.15.",
Py_TYPE(self)->tp_name, key
) < 0) {
res = -1;
goto cleanup;
}
}
}
res = PyObject_SetAttr(self, key, value);
if (res < 0) {
goto cleanup;
}
}
}
Py_ssize_t size = PySet_Size(remaining_fields);
PyObject *field_types = NULL, *remaining_list = NULL;
if (size > 0) {
if (PyObject_GetOptionalAttr((PyObject*)Py_TYPE(self), &_Py_ID(_field_types),
&field_types) < 0) {
res = -1;
goto cleanup;
}
if (field_types == NULL) {
// Probably a user-defined subclass of AST that lacks _field_types.
// This will continue to work as it did before 3.13; i.e., attributes
// that are not passed in simply do not exist on the instance.
goto cleanup;
}
remaining_list = PySequence_List(remaining_fields);
if (!remaining_list) {
goto set_remaining_cleanup;
}
for (Py_ssize_t i = 0; i < size; i++) {
PyObject *name = PyList_GET_ITEM(remaining_list, i);
PyObject *type = PyDict_GetItemWithError(field_types, name);
if (!type) {
if (PyErr_Occurred()) {
goto set_remaining_cleanup;
}
else {
if (PyErr_WarnFormat(
PyExc_DeprecationWarning, 1,
"Field '%U' is missing from %.400s._field_types. "
"This will become an error in Python 3.15.",
name, Py_TYPE(self)->tp_name
) < 0) {
goto set_remaining_cleanup;
}
}
}
else if (_PyUnion_Check(type)) {
// optional field
// do nothing, we'll have set a None default on the class
}
else if (Py_IS_TYPE(type, &Py_GenericAliasType)) {
// list field
PyObject *empty = PyList_New(0);
if (!empty) {
goto set_remaining_cleanup;
}
res = PyObject_SetAttr(self, name, empty);
Py_DECREF(empty);
if (res < 0) {
goto set_remaining_cleanup;
}
}
else if (type == state->expr_context_type) {
// special case for expr_context: default to Load()
res = PyObject_SetAttr(self, name, state->Load_singleton);
if (res < 0) {
goto set_remaining_cleanup;
}
}
else {
// simple field (e.g., identifier)
if (PyErr_WarnFormat(
PyExc_DeprecationWarning, 1,
"%.400s.__init__ missing 1 required positional argument: '%U'. "
"This will become an error in Python 3.15.",
Py_TYPE(self)->tp_name, name
) < 0) {
goto set_remaining_cleanup;
}
}
}
Py_DECREF(remaining_list);
Py_DECREF(field_types);
}
cleanup:
Py_XDECREF(attributes);
Py_XDECREF(fields);
Py_XDECREF(remaining_fields);
return res;
set_remaining_cleanup:
Py_XDECREF(remaining_list);
Py_XDECREF(field_types);
res = -1;
goto cleanup;
}
/* Pickling support */
static PyObject *
ast_type_reduce(PyObject *self, PyObject *unused)
{
struct ast_state *state = get_ast_state();
if (state == NULL) {
return NULL;
}
PyObject *dict = NULL, *fields = NULL, *positional_args = NULL;
if (PyObject_GetOptionalAttr(self, state->__dict__, &dict) < 0) {
return NULL;
}
PyObject *result = NULL;
if (dict) {
// Unpickling (or copying) works as follows:
// - Construct the object with only positional arguments
// - Set the fields from the dict
// We have two constraints:
// - We must set all the required fields in the initial constructor call,
// or the unpickling or deepcopying of the object will trigger DeprecationWarnings.
// - We must not include child nodes in the positional args, because
// that may trigger runaway recursion during copying (gh-120108).
// To satisfy both constraints, we set all the fields to None in the
// initial list of positional args, and then set the fields from the dict.
if (PyObject_GetOptionalAttr((PyObject*)Py_TYPE(self), state->_fields, &fields) < 0) {
goto cleanup;
}
if (fields) {
Py_ssize_t numfields = PySequence_Size(fields);
if (numfields == -1) {
Py_DECREF(dict);
goto cleanup;
}
positional_args = PyList_New(0);
if (!positional_args) {
goto cleanup;
}
for (Py_ssize_t i = 0; i < numfields; i++) {
PyObject *name = PySequence_GetItem(fields, i);
if (!name) {
goto cleanup;
}
PyObject *value;
int rc = PyDict_GetItemRef(dict, name, &value);
Py_DECREF(name);
if (rc < 0) {
goto cleanup;
}
if (!value) {
break;
}
rc = PyList_Append(positional_args, Py_None);
Py_DECREF(value);
if (rc < 0) {
goto cleanup;
}
}
PyObject *args_tuple = PyList_AsTuple(positional_args);
if (!args_tuple) {
goto cleanup;
}
result = Py_BuildValue("ONN", Py_TYPE(self), args_tuple, dict);
}
else {
result = Py_BuildValue("O()N", Py_TYPE(self), dict);
}
}
else {
result = Py_BuildValue("O()", Py_TYPE(self));
}
cleanup:
Py_XDECREF(fields);
Py_XDECREF(positional_args);
return result;
}
/*
* Perform the following validations:
*
* - All keyword arguments are known 'fields' or 'attributes'.
* - No field or attribute would be left unfilled after copy.replace().
*
* On success, this returns 1. Otherwise, set a TypeError
* exception and returns -1 (no exception is set if some
* other internal errors occur).
*
* Parameters
*
* self The AST node instance.
* dict The AST node instance dictionary (self.__dict__).
* fields The list of fields (self._fields).
* attributes The list of attributes (self._attributes).
* kwargs Keyword arguments passed to ast_type_replace().
*
* The 'dict', 'fields', 'attributes' and 'kwargs' arguments can be NULL.
*
* Note: this function can be removed in 3.15 since the verification
* will be done inside the constructor.
*/
static inline int
ast_type_replace_check(PyObject *self,
PyObject *dict,
PyObject *fields,
PyObject *attributes,
PyObject *kwargs)
{
// While it is possible to make some fast paths that would avoid
// allocating objects on the stack, this would cost us readability.
// For instance, if 'fields' and 'attributes' are both empty, and
// 'kwargs' is not empty, we could raise a TypeError immediately.
PyObject *expecting = PySet_New(fields);
if (expecting == NULL) {
return -1;
}
if (attributes) {
if (_PySet_Update(expecting, attributes) < 0) {
Py_DECREF(expecting);
return -1;
}
}
// Any keyword argument that is neither a field nor attribute is rejected.
// We first need to check whether a keyword argument is accepted or not.
// If all keyword arguments are accepted, we compute the required fields
// and attributes. A field or attribute is not needed if:
//
// 1) it is given in 'kwargs', or
// 2) it already exists on 'self'.
if (kwargs) {
Py_ssize_t pos = 0;
PyObject *key, *value;
while (PyDict_Next(kwargs, &pos, &key, &value)) {
int rc = PySet_Discard(expecting, key);
if (rc < 0) {
Py_DECREF(expecting);
return -1;
}
if (rc == 0) {
PyErr_Format(PyExc_TypeError,
"%.400s.__replace__ got an unexpected keyword "
"argument '%U'.", Py_TYPE(self)->tp_name, key);
Py_DECREF(expecting);
return -1;
}
}
}
// check that the remaining fields or attributes would be filled
if (dict) {
Py_ssize_t pos = 0;
PyObject *key, *value;
while (PyDict_Next(dict, &pos, &key, &value)) {
// Mark fields or attributes that are found on the instance
// as non-mandatory. If they are not given in 'kwargs', they
// will be shallow-coied; otherwise, they would be replaced
// (not in this function).
if (PySet_Discard(expecting, key) < 0) {
Py_DECREF(expecting);
return -1;
}
}
if (attributes) {
// Some attributes may or may not be present at runtime.
// In particular, now that we checked whether 'kwargs'
// is correct or not, we allow any attribute to be missing.
//
// Note that fields must still be entirely determined when
// calling the constructor later.
PyObject *unused = PyObject_CallMethodOneArg(expecting,
&_Py_ID(difference_update),
attributes);
if (unused == NULL) {
Py_DECREF(expecting);
return -1;
}
Py_DECREF(unused);
}
}
// Now 'expecting' contains the fields or attributes
// that would not be filled inside ast_type_replace().
Py_ssize_t m = PySet_GET_SIZE(expecting);
if (m > 0) {
PyObject *names = PyList_New(m);
if (names == NULL) {
Py_DECREF(expecting);
return -1;
}
Py_ssize_t i = 0, pos = 0;
PyObject *item;
Py_hash_t hash;
while (_PySet_NextEntry(expecting, &pos, &item, &hash)) {
PyObject *name = PyObject_Repr(item);
if (name == NULL) {
Py_DECREF(expecting);
Py_DECREF(names);
return -1;
}
// steal the reference 'name'
PyList_SET_ITEM(names, i++, name);
}
Py_DECREF(expecting);
if (PyList_Sort(names) < 0) {
Py_DECREF(names);
return -1;
}
PyObject *sep = PyUnicode_FromString(", ");
if (sep == NULL) {
Py_DECREF(names);
return -1;
}
PyObject *str_names = PyUnicode_Join(sep, names);
Py_DECREF(sep);
Py_DECREF(names);
if (str_names == NULL) {
return -1;
}
PyErr_Format(PyExc_TypeError,
"%.400s.__replace__ missing %ld keyword argument%s: %U.",
Py_TYPE(self)->tp_name, m, m == 1 ? "" : "s", str_names);
Py_DECREF(str_names);
return -1;
}
else {
Py_DECREF(expecting);
return 1;
}
}
/*
* Python equivalent:
*
* for key in keys:
* if hasattr(self, key):
* payload[key] = getattr(self, key)
*
* The 'keys' argument is a sequence corresponding to
* the '_fields' or the '_attributes' of an AST node.
*
* This returns -1 if an error occurs and 0 otherwise.
*
* Parameters
*
* payload A dictionary to fill.
* keys A sequence of keys or NULL for an empty sequence.
* dict The AST node instance dictionary (must not be NULL).
*/
static inline int
ast_type_replace_update_payload(PyObject *payload,
PyObject *keys,
PyObject *dict)
{
assert(dict != NULL);
if (keys == NULL) {
return 0;
}
Py_ssize_t n = PySequence_Size(keys);
if (n == -1) {
return -1;
}
for (Py_ssize_t i = 0; i < n; i++) {
PyObject *key = PySequence_GetItem(keys, i);
if (key == NULL) {
return -1;
}
PyObject *value;
if (PyDict_GetItemRef(dict, key, &value) < 0) {
Py_DECREF(key);
return -1;
}
if (value == NULL) {
Py_DECREF(key);
// If a field or attribute is not present at runtime, it should
// be explicitly given in 'kwargs'. If not, the constructor will
// issue a warning (which becomes an error in 3.15).
continue;
}
int rc = PyDict_SetItem(payload, key, value);
Py_DECREF(key);
Py_DECREF(value);
if (rc < 0) {
return -1;
}
}
return 0;
}
/* copy.replace() support (shallow copy) */
static PyObject *
ast_type_replace(PyObject *self, PyObject *args, PyObject *kwargs)
{
if (!_PyArg_NoPositional("__replace__", args)) {
return NULL;
}
struct ast_state *state = get_ast_state();
if (state == NULL) {
return NULL;
}
PyObject *result = NULL;
// known AST class fields and attributes
PyObject *fields = NULL, *attributes = NULL;
// current instance dictionary
PyObject *dict = NULL;
// constructor positional and keyword arguments
PyObject *empty_tuple = NULL, *payload = NULL;
PyObject *type = (PyObject *)Py_TYPE(self);
if (PyObject_GetOptionalAttr(type, state->_fields, &fields) < 0) {
goto cleanup;
}
if (PyObject_GetOptionalAttr(type, state->_attributes, &attributes) < 0) {
goto cleanup;
}
if (PyObject_GetOptionalAttr(self, state->__dict__, &dict) < 0) {
goto cleanup;
}
if (ast_type_replace_check(self, dict, fields, attributes, kwargs) < 0) {
goto cleanup;
}
empty_tuple = PyTuple_New(0);
if (empty_tuple == NULL) {
goto cleanup;
}
payload = PyDict_New();
if (payload == NULL) {
goto cleanup;
}
if (dict) { // in case __dict__ is missing (for some obscure reason)
// copy the instance's fields (possibly NULL)
if (ast_type_replace_update_payload(payload, fields, dict) < 0) {
goto cleanup;
}
// copy the instance's attributes (possibly NULL)
if (ast_type_replace_update_payload(payload, attributes, dict) < 0) {
goto cleanup;
}
}
if (kwargs && PyDict_Update(payload, kwargs) < 0) {
goto cleanup;
}
result = PyObject_Call(type, empty_tuple, payload);
cleanup:
Py_XDECREF(payload);
Py_XDECREF(empty_tuple);
Py_XDECREF(dict);
Py_XDECREF(attributes);
Py_XDECREF(fields);
return result;
}
static PyMemberDef ast_type_members[] = {
{"__dictoffset__", Py_T_PYSSIZET, offsetof(AST_object, dict), Py_READONLY},
{NULL} /* Sentinel */
};
static PyMethodDef ast_type_methods[] = {
{"__reduce__", ast_type_reduce, METH_NOARGS, NULL},
{"__replace__", _PyCFunction_CAST(ast_type_replace), METH_VARARGS | METH_KEYWORDS,
PyDoc_STR("__replace__($self, /, **fields)\\n--\\n\\n"
"Return a copy of the AST node with new values "
"for the specified fields.")},
{NULL}
};
static PyGetSetDef ast_type_getsets[] = {
{"__dict__", PyObject_GenericGetDict, PyObject_GenericSetDict},
{NULL}
};
static PyType_Slot AST_type_slots[] = {
{Py_tp_dealloc, ast_dealloc},
{Py_tp_getattro, PyObject_GenericGetAttr},
{Py_tp_setattro, PyObject_GenericSetAttr},
{Py_tp_traverse, ast_traverse},
{Py_tp_clear, ast_clear},
{Py_tp_members, ast_type_members},
{Py_tp_methods, ast_type_methods},
{Py_tp_getset, ast_type_getsets},
{Py_tp_init, ast_type_init},
{Py_tp_alloc, PyType_GenericAlloc},
{Py_tp_new, PyType_GenericNew},
{Py_tp_free, PyObject_GC_Del},
{0, 0},
};
static PyType_Spec AST_type_spec = {
"ast.AST",
sizeof(AST_object),
0,
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC,
AST_type_slots
};
static PyObject *
make_type(struct ast_state *state, const char *type, PyObject* base,
const char* const* fields, int num_fields, const char *doc)
{
PyObject *fnames, *result;
int i;
fnames = PyTuple_New(num_fields);
if (!fnames) return NULL;
for (i = 0; i < num_fields; i++) {
PyObject *field = PyUnicode_InternFromString(fields[i]);
if (!field) {
Py_DECREF(fnames);
return NULL;
}
PyTuple_SET_ITEM(fnames, i, field);
}
result = PyObject_CallFunction((PyObject*)&PyType_Type, "s(O){OOOOOOOs}",
type, base,
state->_fields, fnames,
state->__match_args__, fnames,
state->__module__,
state->ast,
state->__doc__, doc);
Py_DECREF(fnames);
return result;
}
static int
add_attributes(struct ast_state *state, PyObject *type, const char * const *attrs, int num_fields)
{
int i, result;
PyObject *s, *l = PyTuple_New(num_fields);
if (!l)
return -1;
for (i = 0; i < num_fields; i++) {
s = PyUnicode_InternFromString(attrs[i]);
if (!s) {
Py_DECREF(l);
return -1;
}
PyTuple_SET_ITEM(l, i, s);
}
result = PyObject_SetAttr(type, state->_attributes, l);
Py_DECREF(l);
return result;
}
/* Conversion AST -> Python */
static PyObject* ast2obj_list(struct ast_state *state, struct validator *vstate, asdl_seq *seq,
PyObject* (*func)(struct ast_state *state, struct validator *vstate, void*))
{
Py_ssize_t i, n = asdl_seq_LEN(seq);
PyObject *result = PyList_New(n);
PyObject *value;
if (!result)
return NULL;
for (i = 0; i < n; i++) {
value = func(state, vstate, asdl_seq_GET_UNTYPED(seq, i));
if (!value) {
Py_DECREF(result);
return NULL;
}
PyList_SET_ITEM(result, i, value);
}
return result;
}
static PyObject* ast2obj_object(struct ast_state *Py_UNUSED(state), struct validator *Py_UNUSED(vstate), void *o)
{
PyObject *op = (PyObject*)o;
if (!op) {
op = Py_None;
}
return Py_NewRef(op);
}
#define ast2obj_constant ast2obj_object
#define ast2obj_identifier ast2obj_object
#define ast2obj_string ast2obj_object
static PyObject* ast2obj_int(struct ast_state *Py_UNUSED(state), struct validator *Py_UNUSED(vstate), long b)
{
return PyLong_FromLong(b);
}
/* Conversion Python -> AST */
static int obj2ast_object(struct ast_state *Py_UNUSED(state), PyObject* obj, PyObject** out, PyArena* arena)
{
if (obj == Py_None)
obj = NULL;
if (obj) {
if (_PyArena_AddPyObject(arena, obj) < 0) {
*out = NULL;
return -1;
}
*out = Py_NewRef(obj);
}
else {
*out = NULL;
}
return 0;
}
static int obj2ast_constant(struct ast_state *Py_UNUSED(state), PyObject* obj, PyObject** out, PyArena* arena)
{
if (_PyArena_AddPyObject(arena, obj) < 0) {
*out = NULL;
return -1;
}
*out = Py_NewRef(obj);
return 0;
}
static int obj2ast_identifier(struct ast_state *state, PyObject* obj, PyObject** out, PyArena* arena)
{
if (!PyUnicode_CheckExact(obj) && obj != Py_None) {
PyErr_SetString(PyExc_TypeError, "AST identifier must be of type str");
return -1;
}
return obj2ast_object(state, obj, out, arena);
}
static int obj2ast_string(struct ast_state *state, PyObject* obj, PyObject** out, PyArena* arena)
{
if (!PyUnicode_CheckExact(obj) && !PyBytes_CheckExact(obj)) {
PyErr_SetString(PyExc_TypeError, "AST string must be of type str");
return -1;
}
return obj2ast_object(state, obj, out, arena);
}
static int obj2ast_int(struct ast_state* Py_UNUSED(state), PyObject* obj, int* out, PyArena* arena)
{
int i;
if (!PyLong_Check(obj)) {
PyErr_Format(PyExc_ValueError, "invalid integer value: %R", obj);
return -1;
}
i = PyLong_AsInt(obj);
if (i == -1 && PyErr_Occurred())
return -1;
*out = i;
return 0;
}
static int add_ast_fields(struct ast_state *state)
{
PyObject *empty_tuple;
empty_tuple = PyTuple_New(0);
if (!empty_tuple ||
PyObject_SetAttrString(state->AST_type, "_fields", empty_tuple) < 0 ||
PyObject_SetAttrString(state->AST_type, "__match_args__", empty_tuple) < 0 ||
PyObject_SetAttrString(state->AST_type, "_attributes", empty_tuple) < 0) {
Py_XDECREF(empty_tuple);
return -1;
}
Py_DECREF(empty_tuple);
return 0;
}
""", 0, reflow=False)
self.file.write(textwrap.dedent('''
static int
init_types(struct ast_state *state)
{
if (init_identifiers(state) < 0) {
return -1;
}
state->AST_type = PyType_FromSpec(&AST_type_spec);
if (!state->AST_type) {
return -1;
}
if (add_ast_fields(state) < 0) {
return -1;
}
'''))
for dfn in mod.dfns:
self.visit(dfn)
self.file.write(textwrap.dedent('''
if (!add_ast_annotations(state)) {
return -1;
}
return 0;
}
'''))
def visitProduct(self, prod, name):
if prod.fields:
fields = name+"_fields"
else:
fields = "NULL"
self.emit('state->%s_type = make_type(state, "%s", state->AST_type, %s, %d,' %
(name, name, fields, len(prod.fields)), 1)
self.emit('%s);' % reflow_c_string(asdl_of(name, prod), 2), 2, reflow=False)
self.emit("if (!state->%s_type) return -1;" % name, 1)
if prod.attributes:
self.emit("if (add_attributes(state, state->%s_type, %s_attributes, %d) < 0) return -1;" %
(name, name, len(prod.attributes)), 1)
else:
self.emit("if (add_attributes(state, state->%s_type, NULL, 0) < 0) return -1;" % name, 1)
self.emit_defaults(name, prod.fields, 1)
self.emit_defaults(name, prod.attributes, 1)
def visitSum(self, sum, name):
self.emit('state->%s_type = make_type(state, "%s", state->AST_type, NULL, 0,' %
(name, name), 1)
self.emit('%s);' % reflow_c_string(asdl_of(name, sum), 2), 2, reflow=False)
self.emit("if (!state->%s_type) return -1;" % name, 1)
if sum.attributes:
self.emit("if (add_attributes(state, state->%s_type, %s_attributes, %d) < 0) return -1;" %
(name, name, len(sum.attributes)), 1)
else:
self.emit("if (add_attributes(state, state->%s_type, NULL, 0) < 0) return -1;" % name, 1)
self.emit_defaults(name, sum.attributes, 1)
simple = is_simple(sum)
for t in sum.types:
self.visitConstructor(t, name, simple)
def visitConstructor(self, cons, name, simple):
if cons.fields:
fields = cons.name+"_fields"
else:
fields = "NULL"
self.emit('state->%s_type = make_type(state, "%s", state->%s_type, %s, %d,' %
(cons.name, cons.name, name, fields, len(cons.fields)), 1)
self.emit('%s);' % reflow_c_string(asdl_of(cons.name, cons), 2), 2, reflow=False)
self.emit("if (!state->%s_type) return -1;" % cons.name, 1)
self.emit_defaults(cons.name, cons.fields, 1)
if simple:
self.emit("state->%s_singleton = PyType_GenericNew((PyTypeObject *)"
"state->%s_type, NULL, NULL);" %
(cons.name, cons.name), 1)
self.emit("if (!state->%s_singleton) return -1;" % cons.name, 1)
def emit_defaults(self, name, fields, depth):
for field in fields:
if field.opt:
self.emit('if (PyObject_SetAttr(state->%s_type, state->%s, Py_None) == -1)' %
(name, field.name), depth)
self.emit("return -1;", depth+1)
class ASTModuleVisitor(PickleVisitor):
def visitModule(self, mod):
self.emit("static int", 0)
self.emit("astmodule_exec(PyObject *m)", 0)
self.emit("{", 0)
self.emit('struct ast_state *state = get_ast_state();', 1)
self.emit('if (state == NULL) {', 1)
self.emit('return -1;', 2)
self.emit('}', 1)
self.emit('if (PyModule_AddObjectRef(m, "AST", state->AST_type) < 0) {', 1)
self.emit('return -1;', 2)
self.emit('}', 1)
self.emit('if (PyModule_AddIntMacro(m, PyCF_ALLOW_TOP_LEVEL_AWAIT) < 0) {', 1)
self.emit("return -1;", 2)
self.emit('}', 1)
self.emit('if (PyModule_AddIntMacro(m, PyCF_ONLY_AST) < 0) {', 1)
self.emit("return -1;", 2)
self.emit('}', 1)
self.emit('if (PyModule_AddIntMacro(m, PyCF_TYPE_COMMENTS) < 0) {', 1)
self.emit("return -1;", 2)
self.emit('}', 1)
self.emit('if (PyModule_AddIntMacro(m, PyCF_OPTIMIZED_AST) < 0) {', 1)
self.emit("return -1;", 2)
self.emit('}', 1)
for dfn in mod.dfns:
self.visit(dfn)
self.emit("return 0;", 1)
self.emit("}", 0)
self.emit("", 0)
self.emit("""
static PyModuleDef_Slot astmodule_slots[] = {
{Py_mod_exec, astmodule_exec},
{Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
{Py_mod_gil, Py_MOD_GIL_NOT_USED},
{0, NULL}
};
static struct PyModuleDef _astmodule = {
PyModuleDef_HEAD_INIT,
.m_name = "_ast",
// The _ast module uses a per-interpreter state (PyInterpreterState.ast)
.m_size = 0,
.m_slots = astmodule_slots,
};
PyMODINIT_FUNC
PyInit__ast(void)
{
return PyModuleDef_Init(&_astmodule);
}
""".strip(), 0, reflow=False)
def visitProduct(self, prod, name):
self.addObj(name)
def visitSum(self, sum, name):
self.addObj(name)
for t in sum.types:
self.visitConstructor(t, name)
def visitConstructor(self, cons, name):
self.addObj(cons.name)
def addObj(self, name):
self.emit("if (PyModule_AddObjectRef(m, \"%s\", "
"state->%s_type) < 0) {" % (name, name), 1)
self.emit("return -1;", 2)
self.emit('}', 1)
class StaticVisitor(PickleVisitor):
CODE = '''Very simple, always emit this static code. Override CODE'''
def visit(self, object):
self.emit(self.CODE, 0, reflow=False)
class ObjVisitor(PickleVisitor):
def func_begin(self, name):
ctype = get_c_type(name)
self.emit("PyObject*", 0)
self.emit("ast2obj_%s(struct ast_state *state, struct validator *vstate, void* _o)" % (name), 0)
self.emit("{", 0)
self.emit("%s o = (%s)_o;" % (ctype, ctype), 1)
self.emit("PyObject *result = NULL, *value = NULL;", 1)
self.emit("PyTypeObject *tp;", 1)
self.emit('if (!o) {', 1)
self.emit("Py_RETURN_NONE;", 2)
self.emit("}", 1)
self.emit("if (++vstate->recursion_depth > vstate->recursion_limit) {", 1)
self.emit("PyErr_SetString(PyExc_RecursionError,", 2)
self.emit('"maximum recursion depth exceeded during ast construction");', 3)
self.emit("return NULL;", 2)
self.emit("}", 1)
def func_end(self):
self.emit("vstate->recursion_depth--;", 1)
self.emit("return result;", 1)
self.emit("failed:", 0)
self.emit("vstate->recursion_depth--;", 1)
self.emit("Py_XDECREF(value);", 1)
self.emit("Py_XDECREF(result);", 1)
self.emit("return NULL;", 1)
self.emit("}", 0)
self.emit("", 0)
def visitSum(self, sum, name):
if is_simple(sum):
self.simpleSum(sum, name)
return
self.func_begin(name)
self.emit("switch (o->kind) {", 1)
for i in range(len(sum.types)):
t = sum.types[i]
self.visitConstructor(t, i + 1, name)
self.emit("}", 1)
for a in sum.attributes:
self.emit("value = ast2obj_%s(state, vstate, o->%s);" % (a.type, a.name), 1)
self.emit("if (!value) goto failed;", 1)
self.emit('if (PyObject_SetAttr(result, state->%s, value) < 0)' % a.name, 1)
self.emit('goto failed;', 2)
self.emit('Py_DECREF(value);', 1)
self.func_end()
def simpleSum(self, sum, name):
self.emit("PyObject* ast2obj_%s(struct ast_state *state, struct validator *vstate, %s_ty o)" % (name, name), 0)
self.emit("{", 0)
self.emit("switch(o) {", 1)
for t in sum.types:
self.emit("case %s:" % t.name, 2)
self.emit("return Py_NewRef(state->%s_singleton);" % t.name, 3)
self.emit("}", 1)
self.emit("Py_UNREACHABLE();", 1);
self.emit("}", 0)
def visitProduct(self, prod, name):
self.func_begin(name)
self.emit("tp = (PyTypeObject *)state->%s_type;" % name, 1)
self.emit("result = PyType_GenericNew(tp, NULL, NULL);", 1);
self.emit("if (!result) return NULL;", 1)
for field in prod.fields:
self.visitField(field, name, 1, True)
for a in prod.attributes:
self.emit("value = ast2obj_%s(state, vstate, o->%s);" % (a.type, a.name), 1)
self.emit("if (!value) goto failed;", 1)
self.emit("if (PyObject_SetAttr(result, state->%s, value) < 0)" % a.name, 1)
self.emit('goto failed;', 2)
self.emit('Py_DECREF(value);', 1)
self.func_end()
def visitConstructor(self, cons, enum, name):
self.emit("case %s_kind:" % cons.name, 1)
self.emit("tp = (PyTypeObject *)state->%s_type;" % cons.name, 2)
self.emit("result = PyType_GenericNew(tp, NULL, NULL);", 2);
self.emit("if (!result) goto failed;", 2)
for f in cons.fields:
self.visitField(f, cons.name, 2, False)
self.emit("break;", 2)
def visitField(self, field, name, depth, product):
def emit(s, d):
self.emit(s, depth + d)
if product:
value = "o->%s" % field.name
else:
value = "o->v.%s.%s" % (name, field.name)
self.set(field, value, depth)
emit("if (!value) goto failed;", 0)
emit("if (PyObject_SetAttr(result, state->%s, value) == -1)" % field.name, 0)
emit("goto failed;", 1)
emit("Py_DECREF(value);", 0)
def set(self, field, value, depth):
if field.seq:
if field.type in self.metadata.simple_sums:
# While the sequence elements are stored as void*,
# simple sums expects an enum
self.emit("{", depth)
self.emit("Py_ssize_t i, n = asdl_seq_LEN(%s);" % value, depth+1)
self.emit("value = PyList_New(n);", depth+1)
self.emit("if (!value) goto failed;", depth+1)
self.emit("for(i = 0; i < n; i++)", depth+1)
# This cannot fail, so no need for error handling
self.emit(
"PyList_SET_ITEM(value, i, ast2obj_{0}(state, vstate, ({0}_ty)asdl_seq_GET({1}, i)));".format(
field.type,
value
),
depth + 2,
reflow=False,
)
self.emit("}", depth)
else:
self.emit("value = ast2obj_list(state, vstate, (asdl_seq*)%s, ast2obj_%s);" % (value, field.type), depth)
else:
self.emit("value = ast2obj_%s(state, vstate, %s);" % (field.type, value), depth, reflow=False)
class PartingShots(StaticVisitor):
CODE = """
PyObject* PyAST_mod2obj(mod_ty t)
{
struct ast_state *state = get_ast_state();
if (state == NULL) {
return NULL;
}
int starting_recursion_depth;
/* Be careful here to prevent overflow. */
PyThreadState *tstate = _PyThreadState_GET();
if (!tstate) {
return NULL;
}
struct validator vstate;
vstate.recursion_limit = Py_C_RECURSION_LIMIT;
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
starting_recursion_depth = recursion_depth;
vstate.recursion_depth = starting_recursion_depth;
PyObject *result = ast2obj_mod(state, &vstate, t);
/* Check that the recursion depth counting balanced correctly */
if (result && vstate.recursion_depth != starting_recursion_depth) {
PyErr_Format(PyExc_SystemError,
"AST constructor recursion depth mismatch (before=%d, after=%d)",
starting_recursion_depth, vstate.recursion_depth);
return NULL;
}
return result;
}
/* mode is 0 for "exec", 1 for "eval" and 2 for "single" input */
mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode)
{
const char * const req_name[] = {"Module", "Expression", "Interactive"};
int isinstance;
if (PySys_Audit("compile", "OO", ast, Py_None) < 0) {
return NULL;
}
struct ast_state *state = get_ast_state();
if (state == NULL) {
return NULL;
}
PyObject *req_type[3];
req_type[0] = state->Module_type;
req_type[1] = state->Expression_type;
req_type[2] = state->Interactive_type;
assert(0 <= mode && mode <= 2);
isinstance = PyObject_IsInstance(ast, req_type[mode]);
if (isinstance == -1)
return NULL;
if (!isinstance) {
PyErr_Format(PyExc_TypeError, "expected %s node, got %.400s",
req_name[mode], _PyType_Name(Py_TYPE(ast)));
return NULL;
}
mod_ty res = NULL;
if (obj2ast_mod(state, ast, &res, arena) != 0)
return NULL;
else
return res;
}
int PyAST_Check(PyObject* obj)
{
struct ast_state *state = get_ast_state();
if (state == NULL) {
return -1;
}
return PyObject_IsInstance(obj, state->AST_type);
}
"""
class ChainOfVisitors:
def __init__(self, *visitors, metadata = None):
self.visitors = visitors
self.metadata = metadata
def visit(self, object):
for v in self.visitors:
v.metadata = self.metadata
v.visit(object)
v.emit("", 0)
def generate_ast_state(module_state, f):
f.write('struct ast_state {\n')
f.write(' _PyOnceFlag once;\n')
f.write(' int finalized;\n')
for s in module_state:
f.write(' PyObject *' + s + ';\n')
f.write('};')
def generate_ast_fini(module_state, f):
f.write(textwrap.dedent("""
void _PyAST_Fini(PyInterpreterState *interp)
{
struct ast_state *state = &interp->ast;
"""))
for s in module_state:
f.write(" Py_CLEAR(state->" + s + ');\n')
f.write(textwrap.dedent("""
Py_CLEAR(_Py_INTERP_CACHED_OBJECT(interp, str_replace_inf));
state->finalized = 1;
state->once = (_PyOnceFlag){0};
}
"""))
def generate_module_def(mod, metadata, f, internal_h):
# Gather all the data needed for ModuleSpec
state_strings = {
"ast",
"_fields",
"__match_args__",
"__doc__",
"__dict__",
"__module__",
"_attributes",
*metadata.identifiers
}
module_state = state_strings.copy()
module_state.update(
"%s_singleton" % singleton
for singleton in metadata.singletons
)
module_state.update(
"%s_type" % type
for type in metadata.types
)
state_strings = sorted(state_strings)
module_state = sorted(module_state)
generate_ast_state(module_state, internal_h)
print(textwrap.dedent("""
#include "Python.h"
#include "pycore_ast.h"
#include "pycore_ast_state.h" // struct ast_state
#include "pycore_ceval.h" // _Py_EnterRecursiveCall
#include "pycore_lock.h" // _PyOnceFlag
#include "pycore_interp.h" // _PyInterpreterState.ast
#include "pycore_modsupport.h" // _PyArg_NoPositional()
#include "pycore_pystate.h" // _PyInterpreterState_GET()
#include "pycore_setobject.h" // _PySet_NextEntry(), _PySet_Update()
#include "pycore_unionobject.h" // _Py_union_type_or
#include "structmember.h"
#include <stddef.h>
struct validator {
int recursion_depth; /* current recursion depth */
int recursion_limit; /* recursion limit */
};
// Forward declaration
static int init_types(struct ast_state *state);
static struct ast_state*
get_ast_state(void)
{
PyInterpreterState *interp = _PyInterpreterState_GET();
struct ast_state *state = &interp->ast;
assert(!state->finalized);
if (_PyOnceFlag_CallOnce(&state->once, (_Py_once_fn_t *)&init_types, state) < 0) {
return NULL;
}
return state;
}
""").strip(), file=f)
generate_ast_fini(module_state, f)
f.write('static int init_identifiers(struct ast_state *state)\n')
f.write('{\n')
for identifier in state_strings:
f.write(' if ((state->' + identifier)
f.write(' = PyUnicode_InternFromString("')
f.write(identifier + '")) == NULL) return -1;\n')
f.write(' return 0;\n')
f.write('};\n\n')
def write_header(mod, metadata, f):
f.write(textwrap.dedent("""
#ifndef Py_INTERNAL_AST_H
#define Py_INTERNAL_AST_H
#ifdef __cplusplus
extern "C" {
#endif
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
#include "pycore_asdl.h" // _ASDL_SEQ_HEAD
""").lstrip())
c = ChainOfVisitors(
TypeDefVisitor(f),
SequenceDefVisitor(f),
StructVisitor(f),
metadata=metadata
)
c.visit(mod)
f.write("// Note: these macros affect function definitions, not only call sites.\n")
prototype_visitor = PrototypeVisitor(f, metadata=metadata)
prototype_visitor.visit(mod)
f.write(textwrap.dedent("""
PyObject* PyAST_mod2obj(mod_ty t);
mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode);
int PyAST_Check(PyObject* obj);
extern int _PyAST_Validate(mod_ty);
/* _PyAST_ExprAsUnicode is defined in ast_unparse.c */
extern PyObject* _PyAST_ExprAsUnicode(expr_ty);
/* Return the borrowed reference to the first literal string in the
sequence of statements or NULL if it doesn't start from a literal string.
Doesn't set exception. */
extern PyObject* _PyAST_GetDocString(asdl_stmt_seq *);
#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_AST_H */
"""))
def write_internal_h_header(mod, f):
print(textwrap.dedent("""
#ifndef Py_INTERNAL_AST_STATE_H
#define Py_INTERNAL_AST_STATE_H
#include "pycore_lock.h" // _PyOnceFlag
#ifdef __cplusplus
extern "C" {
#endif
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
""").lstrip(), file=f)
def write_internal_h_footer(mod, f):
print(textwrap.dedent("""
#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_AST_STATE_H */
"""), file=f)
def write_source(mod, metadata, f, internal_h_file):
generate_module_def(mod, metadata, f, internal_h_file)
v = ChainOfVisitors(
SequenceConstructorVisitor(f),
PyTypesDeclareVisitor(f),
AnnotationsVisitor(f),
PyTypesVisitor(f),
Obj2ModPrototypeVisitor(f),
FunctionVisitor(f),
ObjVisitor(f),
Obj2ModVisitor(f),
ASTModuleVisitor(f),
PartingShots(f),
metadata=metadata
)
v.visit(mod)
def main(input_filename, c_filename, h_filename, internal_h_filename, dump_module=False):
auto_gen_msg = AUTOGEN_MESSAGE.format("/".join(Path(__file__).parts[-2:]))
mod = asdl.parse(input_filename)
if dump_module:
print('Parsed Module:')
print(mod)
if not asdl.check(mod):
sys.exit(1)
metadata_visitor = MetadataVisitor()
metadata_visitor.visit(mod)
metadata = metadata_visitor.metadata
with c_filename.open("w") as c_file, \
h_filename.open("w") as h_file, \
internal_h_filename.open("w") as internal_h_file:
c_file.write(auto_gen_msg)
h_file.write(auto_gen_msg)
internal_h_file.write(auto_gen_msg)
write_internal_h_header(mod, internal_h_file)
write_source(mod, metadata, c_file, internal_h_file)
write_header(mod, metadata, h_file)
write_internal_h_footer(mod, internal_h_file)
print(f"{c_filename}, {h_filename}, {internal_h_filename} regenerated.")
if __name__ == "__main__":
parser = ArgumentParser()
parser.add_argument("input_file", type=Path)
parser.add_argument("-C", "--c-file", type=Path, required=True)
parser.add_argument("-H", "--h-file", type=Path, required=True)
parser.add_argument("-I", "--internal-h-file", type=Path, required=True)
parser.add_argument("-d", "--dump-module", action="store_true")
args = parser.parse_args()
main(args.input_file, args.c_file, args.h_file,
args.internal_h_file, args.dump_module)
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