cpython/Parser/asdl_c.py

1495 lines
49 KiB
Python
Executable File

#! /usr/bin/env python
"""Generate C code from an ASDL description."""
import os
import sys
from argparse import ArgumentParser
from pathlib import Path
import asdl
TABSIZE = 4
MAX_COL = 80
AUTOGEN_MESSAGE = "/* File automatically generated by {}. */\n\n"
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):
"""Return True if a sum is a simple.
A sum is simple if its types have no fields, e.g.
unaryop = Invert | Not | UAdd | USub
"""
for t in sum.types:
if t.fields:
return False
return True
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):
self.file = file
self.identifiers = set()
self.singletons = set()
self.types = set()
super(EmitVisitor, self).__init__()
def emit_identifier(self, name):
self.identifiers.add(str(name))
def emit_singleton(self, name):
self.singletons.add(str(name))
def emit_type(self, name):
self.types.add(str(name))
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")
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 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 == 'cmpop':
self.emit("asdl_int_seq *%(name)s;" % locals(), depth)
else:
self.emit("asdl_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)
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 into, 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 == 'cmpop':
ctype = "asdl_int_seq *"
else:
ctype = "asdl_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"
margs = "a0"
for i in range(1, len(args)+1):
margs += ", a%d" % i
self.emit("#define %s(%s) _Py_%s(%s)" % (name, margs, name, margs), 0,
reflow=False)
self.emit("%s _Py_%s(%s);" % (ctype, 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)" % (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(astmodulestate *state, PyObject* obj, %s* out, PyArena* arena);"
self.emit(code % (name, get_c_type(name)), 0)
visitSum = visitProduct
class Obj2ModVisitor(PickleVisitor):
def funcHeader(self, name):
ctype = get_c_type(name)
self.emit("int", 0)
self.emit("obj2ast_%s(astmodulestate *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);" % (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(astmodulestate *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);" % (name, self.buildArgs(args)), 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:
self.emit("asdl_seq* %s;" % field.name, depth)
else:
ctype = get_c_type(field.type)
self.emit("%s %s;" % (ctype, field.name), depth)
def isSimpleSum(self, field):
# XXX can the members of this list be determined automatically?
return field.type in ('expr_context', 'boolop', 'operator',
'unaryop', 'cmpop')
def isNumeric(self, field):
return get_c_type(field.type) in ("int", "bool")
def isSimpleType(self, field):
return self.isSimpleSum(field) or self.isNumeric(field)
def visitField(self, field, name, sum=None, prod=None, depth=0):
ctype = get_c_type(field.type)
line = "if (_PyObject_LookupAttr(obj, state->%s, &tmp) < 0) {"
self.emit(line % field.name, depth)
self.emit("return 1;", depth+1)
self.emit("}", depth)
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):
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_seq_new(len, arena);" % field.name, 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 = PyList_GET_ITEM(tmp, i);", depth+2)
self.emit("Py_INCREF(tmp2);", 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:
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 MarshalPrototypeVisitor(PickleVisitor):
def prototype(self, sum, name):
ctype = get_c_type(name)
self.emit("static int marshal_write_%s(PyObject **, int *, %s);"
% (name, ctype), 0)
visitProduct = visitSum = prototype
class PyTypesDeclareVisitor(PickleVisitor):
def visitProduct(self, prod, name):
self.emit_type("%s_type" % name)
self.emit("static PyObject* ast2obj_%s(astmodulestate *state, void*);" % name, 0)
if prod.attributes:
for a in prod.attributes:
self.emit_identifier(a.name)
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:
for f in prod.fields:
self.emit_identifier(f.name)
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):
self.emit_type("%s_type" % name)
if sum.attributes:
for a in sum.attributes:
self.emit_identifier(a.name)
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)
for t in sum.types:
self.emit_singleton("%s_singleton" % t.name)
self.emit("static PyObject* ast2obj_%s(astmodulestate *state, %s);" % (name, ptype), 0)
for t in sum.types:
self.visitConstructor(t, name)
def visitConstructor(self, cons, name):
if cons.fields:
for t in cons.fields:
self.emit_identifier(t.name)
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 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)
{
astmodulestate *state = get_global_ast_state();
if (state == NULL) {
return -1;
}
Py_ssize_t i, numfields = 0;
int res = -1;
PyObject *key, *value, *fields;
if (_PyObject_LookupAttr((PyObject*)Py_TYPE(self), state->_fields, &fields) < 0) {
goto cleanup;
}
if (fields) {
numfields = PySequence_Size(fields);
if (numfields == -1) {
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));
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) {
Py_ssize_t p = PySequence_Index(fields, key);
if (p == -1) {
res = -1;
goto cleanup;
}
if (p < PyTuple_GET_SIZE(args)) {
PyErr_Format(PyExc_TypeError,
"%.400s got multiple values for argument '%U'",
Py_TYPE(self)->tp_name, key);
res = -1;
goto cleanup;
}
}
res = PyObject_SetAttr(self, key, value);
if (res < 0) {
goto cleanup;
}
}
}
cleanup:
Py_XDECREF(fields);
return res;
}
/* Pickling support */
static PyObject *
ast_type_reduce(PyObject *self, PyObject *unused)
{
astmodulestate *state = get_global_ast_state();
if (state == NULL) {
return NULL;
}
PyObject *dict;
if (_PyObject_LookupAttr(self, state->__dict__, &dict) < 0) {
return NULL;
}
if (dict) {
return Py_BuildValue("O()N", Py_TYPE(self), dict);
}
return Py_BuildValue("O()", Py_TYPE(self));
}
static PyMemberDef ast_type_members[] = {
{"__dictoffset__", T_PYSSIZET, offsetof(AST_object, dict), READONLY},
{NULL} /* Sentinel */
};
static PyMethodDef ast_type_methods[] = {
{"__reduce__", ast_type_reduce, METH_NOARGS, NULL},
{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(astmodulestate *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){OOOOOs}",
type, base,
state->_fields, fnames,
state->__module__,
state->ast,
state->__doc__, doc);
Py_DECREF(fnames);
return result;
}
static int
add_attributes(astmodulestate *state, PyObject *type, const char * const *attrs, int num_fields)
{
int i, result;
PyObject *s, *l = PyTuple_New(num_fields);
if (!l)
return 0;
for (i = 0; i < num_fields; i++) {
s = PyUnicode_InternFromString(attrs[i]);
if (!s) {
Py_DECREF(l);
return 0;
}
PyTuple_SET_ITEM(l, i, s);
}
result = PyObject_SetAttr(type, state->_attributes, l) >= 0;
Py_DECREF(l);
return result;
}
/* Conversion AST -> Python */
static PyObject* ast2obj_list(astmodulestate *state, asdl_seq *seq, PyObject* (*func)(astmodulestate *state, 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, asdl_seq_GET(seq, i));
if (!value) {
Py_DECREF(result);
return NULL;
}
PyList_SET_ITEM(result, i, value);
}
return result;
}
static PyObject* ast2obj_object(astmodulestate *Py_UNUSED(state), void *o)
{
if (!o)
o = Py_None;
Py_INCREF((PyObject*)o);
return (PyObject*)o;
}
#define ast2obj_constant ast2obj_object
#define ast2obj_identifier ast2obj_object
#define ast2obj_string ast2obj_object
static PyObject* ast2obj_int(astmodulestate *Py_UNUSED(state), long b)
{
return PyLong_FromLong(b);
}
/* Conversion Python -> AST */
static int obj2ast_object(astmodulestate *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;
}
Py_INCREF(obj);
}
*out = obj;
return 0;
}
static int obj2ast_constant(astmodulestate *Py_UNUSED(state), PyObject* obj, PyObject** out, PyArena* arena)
{
if (PyArena_AddPyObject(arena, obj) < 0) {
*out = NULL;
return -1;
}
Py_INCREF(obj);
*out = obj;
return 0;
}
static int obj2ast_identifier(astmodulestate *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(astmodulestate *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(astmodulestate* 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(astmodulestate *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, "_attributes", empty_tuple) < 0) {
Py_XDECREF(empty_tuple);
return -1;
}
Py_DECREF(empty_tuple);
return 0;
}
""", 0, reflow=False)
self.emit("static int init_types(astmodulestate *state)",0)
self.emit("{", 0)
self.emit("if (state->initialized) return 1;", 1)
self.emit("if (init_identifiers(state) < 0) return 0;", 1)
self.emit("state->AST_type = PyType_FromSpec(&AST_type_spec);", 1)
self.emit("if (!state->AST_type) return 0;", 1)
self.emit("if (add_ast_fields(state) < 0) return 0;", 1)
for dfn in mod.dfns:
self.visit(dfn)
self.emit("state->initialized = 1;", 1)
self.emit("return 1;", 1);
self.emit("}", 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 0;" % name, 1)
self.emit_type("AST_type")
self.emit_type("%s_type" % name)
if prod.attributes:
self.emit("if (!add_attributes(state, state->%s_type, %s_attributes, %d)) return 0;" %
(name, name, len(prod.attributes)), 1)
else:
self.emit("if (!add_attributes(state, state->%s_type, NULL, 0)) return 0;" % 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_type("%s_type" % name)
self.emit("if (!state->%s_type) return 0;" % name, 1)
if sum.attributes:
self.emit("if (!add_attributes(state, state->%s_type, %s_attributes, %d)) return 0;" %
(name, name, len(sum.attributes)), 1)
else:
self.emit("if (!add_attributes(state, state->%s_type, NULL, 0)) return 0;" % 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 0;" % cons.name, 1)
self.emit_type("%s_type" % cons.name)
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 0;" % 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 0;", 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('astmodulestate *state = get_ast_state(m);', 1)
self.emit("", 0)
self.emit("if (!init_types(state)) {", 1)
self.emit("return -1;", 2)
self.emit("}", 1)
self.emit('if (PyModule_AddObject(m, "AST", state->AST_type) < 0) {', 1)
self.emit('return -1;', 2)
self.emit('}', 1)
self.emit('Py_INCREF(state->AST_type);', 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)
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},
{0, NULL}
};
static struct PyModuleDef _astmodule = {
PyModuleDef_HEAD_INIT,
.m_name = "_ast",
// The _ast module uses a global state (global_ast_state).
.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_AddObject(m, \"%s\", "
"state->%s_type) < 0) {" % (name, name), 1)
self.emit("return -1;", 2)
self.emit('}', 1)
self.emit("Py_INCREF(state->%s_type);" % name, 1)
_SPECIALIZED_SEQUENCES = ('stmt', 'expr')
def find_sequence(fields, doing_specialization):
"""Return True if any field uses a sequence."""
for f in fields:
if f.seq:
if not doing_specialization:
return True
if str(f.type) not in _SPECIALIZED_SEQUENCES:
return True
return False
def has_sequence(types, doing_specialization):
for t in types:
if find_sequence(t.fields, doing_specialization):
return True
return False
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(astmodulestate *state, 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)
def func_end(self):
self.emit("return result;", 1)
self.emit("failed:", 0)
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, 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(astmodulestate *state, %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("Py_INCREF(state->%s_singleton);" % t.name, 3)
self.emit("return 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, 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 emitSeq(self, field, value, depth, emit):
emit("seq = %s;" % value, 0)
emit("n = asdl_seq_LEN(seq);", 0)
emit("value = PyList_New(n);", 0)
emit("if (!value) goto failed;", 0)
emit("for (i = 0; i < n; i++) {", 0)
self.set("value", field, "asdl_seq_GET(seq, i)", depth + 1)
emit("if (!value1) goto failed;", 1)
emit("PyList_SET_ITEM(value, i, value1);", 1)
emit("value1 = NULL;", 1)
emit("}", 0)
def set(self, field, value, depth):
if field.seq:
# XXX should really check for is_simple, but that requires a symbol table
if field.type == "cmpop":
# While the sequence elements are stored as void*,
# ast2obj_cmpop 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_cmpop(state, (cmpop_ty)asdl_seq_GET(%s, i)));" % value,
depth+2, reflow=False)
self.emit("}", depth)
else:
self.emit("value = ast2obj_list(state, %s, ast2obj_%s);" % (value, field.type), depth)
else:
ctype = get_c_type(field.type)
self.emit("value = ast2obj_%s(state, %s);" % (field.type, value), depth, reflow=False)
class PartingShots(StaticVisitor):
CODE = """
PyObject* PyAST_mod2obj(mod_ty t)
{
astmodulestate *state = get_global_ast_state();
if (state == NULL) {
return NULL;
}
return ast2obj_mod(state, t);
}
/* 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;
}
astmodulestate *state = get_global_ast_state();
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)
{
astmodulestate *state = get_global_ast_state();
if (state == NULL) {
return -1;
}
return PyObject_IsInstance(obj, state->AST_type);
}
"""
class ChainOfVisitors:
def __init__(self, *visitors):
self.visitors = visitors
def visit(self, object):
for v in self.visitors:
v.visit(object)
v.emit("", 0)
def generate_module_def(f, mod):
# Gather all the data needed for ModuleSpec
visitor_list = set()
with open(os.devnull, "w") as devnull:
visitor = PyTypesDeclareVisitor(devnull)
visitor.visit(mod)
visitor_list.add(visitor)
visitor = PyTypesVisitor(devnull)
visitor.visit(mod)
visitor_list.add(visitor)
state_strings = {
"ast",
"_fields",
"__doc__",
"__dict__",
"__module__",
"_attributes",
}
module_state = state_strings.copy()
for visitor in visitor_list:
for identifier in visitor.identifiers:
module_state.add(identifier)
state_strings.add(identifier)
for singleton in visitor.singletons:
module_state.add(singleton)
for tp in visitor.types:
module_state.add(tp)
state_strings = sorted(state_strings)
module_state = sorted(module_state)
f.write('typedef struct {\n')
f.write(' int initialized;\n')
for s in module_state:
f.write(' PyObject *' + s + ';\n')
f.write('} astmodulestate;\n\n')
f.write("""
// Forward declaration
static int init_types(astmodulestate *state);
// bpo-41194, bpo-41261, bpo-41631: The _ast module uses a global state.
static astmodulestate global_ast_state = {0};
static astmodulestate*
get_global_ast_state(void)
{
astmodulestate* state = &global_ast_state;
if (!init_types(state)) {
return NULL;
}
return state;
}
static astmodulestate*
get_ast_state(PyObject* Py_UNUSED(module))
{
astmodulestate* state = get_global_ast_state();
// get_ast_state() must only be called after _ast module is imported,
// and astmodule_exec() calls init_types()
assert(state != NULL);
return state;
}
void _PyAST_Fini()
{
astmodulestate* state = &global_ast_state;
""")
for s in module_state:
f.write(" Py_CLEAR(state->" + s + ');\n')
f.write("""
state->initialized = 0;
}
""")
f.write('static int init_identifiers(astmodulestate *state)\n')
f.write('{\n')
for identifier in state_strings:
f.write(' if ((state->' + identifier)
f.write(' = PyUnicode_InternFromString("')
f.write(identifier + '")) == NULL) return 0;\n')
f.write(' return 1;\n')
f.write('};\n\n')
def write_header(f, mod):
f.write('#ifndef Py_PYTHON_AST_H\n')
f.write('#define Py_PYTHON_AST_H\n')
f.write('#ifdef __cplusplus\n')
f.write('extern "C" {\n')
f.write('#endif\n')
f.write('\n')
f.write('#ifndef Py_LIMITED_API\n')
f.write('#include "asdl.h"\n')
f.write('\n')
f.write('#undef Yield /* undefine macro conflicting with <winbase.h> */\n')
f.write('\n')
c = ChainOfVisitors(TypeDefVisitor(f),
StructVisitor(f))
c.visit(mod)
f.write("// Note: these macros affect function definitions, not only call sites.\n")
PrototypeVisitor(f).visit(mod)
f.write("\n")
f.write("PyObject* PyAST_mod2obj(mod_ty t);\n")
f.write("mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode);\n")
f.write("int PyAST_Check(PyObject* obj);\n")
f.write("#endif /* !Py_LIMITED_API */\n")
f.write('\n')
f.write('#ifdef __cplusplus\n')
f.write('}\n')
f.write('#endif\n')
f.write('#endif /* !Py_PYTHON_AST_H */\n')
def write_source(f, mod):
f.write('#include <stddef.h>\n')
f.write('\n')
f.write('#include "Python.h"\n')
f.write('#include "%s-ast.h"\n' % mod.name)
f.write('#include "structmember.h" // PyMemberDef\n')
f.write('\n')
generate_module_def(f, mod)
v = ChainOfVisitors(
PyTypesDeclareVisitor(f),
PyTypesVisitor(f),
Obj2ModPrototypeVisitor(f),
FunctionVisitor(f),
ObjVisitor(f),
Obj2ModVisitor(f),
ASTModuleVisitor(f),
PartingShots(f),
)
v.visit(mod)
def main(input_file, c_file, h_file, dump_module=False):
auto_gen_msg = AUTOGEN_MESSAGE.format("/".join(Path(__file__).parts[-2:]))
mod = asdl.parse(input_file)
if dump_module:
print('Parsed Module:')
print(mod)
if not asdl.check(mod):
sys.exit(1)
for file, writer in (c_file, write_source), (h_file, write_header):
if file is not None:
with file.open("w") as f:
f.write(auto_gen_msg)
writer(f, mod)
print(file, "regenerated.")
if __name__ == "__main__":
parser = ArgumentParser()
parser.add_argument("input_file", type=Path)
parser.add_argument("-C", "--c-file", type=Path, default=None)
parser.add_argument("-H", "--h-file", type=Path, default=None)
parser.add_argument("-d", "--dump-module", action="store_true")
options = parser.parse_args()
main(**vars(options))