#! /usr/bin/env python

"""Generate C code from an ASDL description."""

import os, sys

import asdl

TABSIZE = 4

MAX_COL = 80

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 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

class EmitVisitor(asdl.VisitorBase):

"""Visit that emits lines"""

def __init__(self, file):

self.file = file

self.identifiers = set()

super(EmitVisitor, self).__init__()

def emit_identifier(self, name):

name = str(name)

if name in self.identifiers:

return

self.emit("_Py_IDENTIFIER(%s);" % name, 0)

self.identifiers.add(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(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(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, "

"(PyObject *)%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)

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:

line = "isinstance = PyObject_IsInstance(obj, (PyObject*)%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)

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(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)

self.emit("if (_PyObject_LookupAttrId(obj, &PyId_%s, &tmp) < 0) {" % 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\", tmp->ob_type->tp_name);" %

(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("res = obj2ast_%s(PyList_GET_ITEM(tmp, i), &val, arena);" %

field.type, depth+2, reflow=False)

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(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("static PyTypeObject *%s_type;" % name, 0)

self.emit("static PyObject* ast2obj_%s(void*);" % name, 0)

if prod.attributes:

for a in prod.attributes:

self.emit_identifier(a.name)

self.emit("static char *%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 char *%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("static PyTypeObject *%s_type;" % name, 0)

if sum.attributes:

for a in sum.attributes:

self.emit_identifier(a.name)

self.emit("static char *%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)

tnames = []

for t in sum.types:

tnames.append(str(t.name)+"_singleton")

tnames = ", *".join(tnames)

self.emit("static PyObject *%s;" % tnames, 0)

self.emit("static PyObject* ast2obj_%s(%s);" % (name, ptype), 0)

for t in sum.types:

self.visitConstructor(t, name)

def visitConstructor(self, cons, name):

self.emit("static PyTypeObject *%s_type;" % cons.name, 0)

if cons.fields:

for t in cons.fields:

self.emit_identifier(t.name)

self.emit("static char *%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("""

_Py_IDENTIFIER(_fields);

_Py_IDENTIFIER(_attributes);

typedef struct {

PyObject_HEAD

PyObject *dict;

} AST_object;

static void

ast_dealloc(AST_object *self)

{

/* bpo-31095: UnTrack is needed before calling any callbacks */

PyObject_GC_UnTrack(self);

Py_CLEAR(self->dict);

Py_TYPE(self)->tp_free(self);

}

static int

ast_traverse(AST_object *self, visitproc visit, void *arg)

{

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)

{

Py_ssize_t i, numfields = 0;

int res = -1;

PyObject *key, *value, *fields;

if (_PyObject_LookupAttrId((PyObject*)Py_TYPE(self), &PyId__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",

Py_TYPE(self)->tp_name,

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)) {

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)

{

_Py_IDENTIFIER(__dict__);

PyObject *dict;

if (_PyObject_LookupAttrId(self, &PyId___dict__, &dict) < 0) {

return NULL;

}

if (dict) {

return Py_BuildValue("O()N", Py_TYPE(self), dict);

}

return Py_BuildValue("O()", Py_TYPE(self));

}

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 PyTypeObject AST_type = {

PyVarObject_HEAD_INIT(&PyType_Type, 0)

"_ast.AST",

sizeof(AST_object),

0,

(destructor)ast_dealloc, /* tp_dealloc */

0, /* tp_print */

0, /* tp_getattr */

0, /* tp_setattr */

0, /* tp_reserved */

0, /* tp_repr */

0, /* tp_as_number */

0, /* tp_as_sequence */

0, /* tp_as_mapping */

0, /* tp_hash */

0, /* tp_call */

0, /* tp_str */

PyObject_GenericGetAttr, /* tp_getattro */

PyObject_GenericSetAttr, /* tp_setattro */

0, /* tp_as_buffer */

Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */

0, /* tp_doc */

(traverseproc)ast_traverse, /* tp_traverse */

(inquiry)ast_clear, /* tp_clear */

0, /* tp_richcompare */

0, /* tp_weaklistoffset */

0, /* tp_iter */

0, /* tp_iternext */

ast_type_methods, /* tp_methods */

0, /* tp_members */

ast_type_getsets, /* tp_getset */

0, /* tp_base */

0, /* tp_dict */

0, /* tp_descr_get */

0, /* tp_descr_set */

offsetof(AST_object, dict),/* tp_dictoffset */

(initproc)ast_type_init, /* tp_init */

PyType_GenericAlloc, /* tp_alloc */

PyType_GenericNew, /* tp_new */

PyObject_GC_Del, /* tp_free */

};

static PyTypeObject* make_type(char *type, PyTypeObject* base, char**fields, int num_fields)

{

_Py_IDENTIFIER(__module__);

_Py_IDENTIFIER(_ast);

PyObject *fnames, *result;

int i;

fnames = PyTuple_New(num_fields);

if (!fnames) return NULL;

for (i = 0; i < num_fields; i++) {

PyObject *field = PyUnicode_FromString(fields[i]);

if (!field) {

Py_DECREF(fnames);

return NULL;

}

PyTuple_SET_ITEM(fnames, i, field);

}

result = PyObject_CallFunction((PyObject*)&PyType_Type, "s(O){OOOO}",

type, base,

_PyUnicode_FromId(&PyId__fields), fnames,

_PyUnicode_FromId(&PyId___module__),

_PyUnicode_FromId(&PyId__ast));

Py_DECREF(fnames);

return (PyTypeObject*)result;

}

static int add_attributes(PyTypeObject* type, char**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_FromString(attrs[i]);

if (!s) {

Py_DECREF(l);

return 0;

}

PyTuple_SET_ITEM(l, i, s);

}

result = _PyObject_SetAttrId((PyObject*)type, &PyId__attributes, l) >= 0;

Py_DECREF(l);

return result;

}

/* Conversion AST -> Python */

static PyObject* ast2obj_list(asdl_seq *seq, PyObject* (*func)(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(asdl_seq_GET(seq, i));

if (!value) {

Py_DECREF(result);

return NULL;

}

PyList_SET_ITEM(result, i, value);

}

return result;

}

static PyObject* ast2obj_object(void *o)

{

if (!o)

o = Py_None;

Py_INCREF((PyObject*)o);

return (PyObject*)o;

}

#define ast2obj_singleton ast2obj_object

#define ast2obj_constant ast2obj_object

#define ast2obj_identifier ast2obj_object

#define ast2obj_string ast2obj_object

#define ast2obj_bytes ast2obj_object

static PyObject* ast2obj_int(long b)

{

return PyLong_FromLong(b);

}

/* Conversion Python -> AST */

static int obj2ast_object(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(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(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(obj, out, arena);

}

static int obj2ast_string(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(obj, out, arena);

}

static int obj2ast_int(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(void)

{

PyObject *empty_tuple, *d;

if (PyType_Ready(&AST_type) < 0)

return -1;

d = AST_type.tp_dict;

empty_tuple = PyTuple_New(0);

if (!empty_tuple ||

_PyDict_SetItemId(d, &PyId__fields, empty_tuple) < 0 ||

_PyDict_SetItemId(d, &PyId__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(void)",0)

self.emit("{", 0)

self.emit("static int initialized;", 1)

self.emit("if (initialized) return 1;", 1)

self.emit("if (add_ast_fields() < 0) return 0;", 1)

for dfn in mod.dfns:

self.visit(dfn)

self.emit("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('%s_type = make_type("%s", &AST_type, %s, %d);' %

(name, name, fields, len(prod.fields)), 1)

self.emit("if (!%s_type) return 0;" % name, 1)

if prod.attributes:

self.emit("if (!add_attributes(%s_type, %s_attributes, %d)) return 0;" %

(name, name, len(prod.attributes)), 1)

else:

self.emit("if (!add_attributes(%s_type, NULL, 0)) return 0;" % name, 1)

def visitSum(self, sum, name):

self.emit('%s_type = make_type("%s", &AST_type, NULL, 0);' %

(name, name), 1)

self.emit("if (!%s_type) return 0;" % name, 1)

if sum.attributes:

self.emit("if (!add_attributes(%s_type, %s_attributes, %d)) return 0;" %

(name, name, len(sum.attributes)), 1)

else:

self.emit("if (!add_attributes(%s_type, NULL, 0)) return 0;" % name, 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('%s_type = make_type("%s", %s_type, %s, %d);' %

(cons.name, cons.name, name, fields, len(cons.fields)), 1)

self.emit("if (!%s_type) return 0;" % cons.name, 1)

if simple:

self.emit("%s_singleton = PyType_GenericNew(%s_type, NULL, NULL);" %

(cons.name, cons.name), 1)

self.emit("if (!%s_singleton) return 0;" % cons.name, 1)

class ASTModuleVisitor(PickleVisitor):

def visitModule(self, mod):

self.emit("static struct PyModuleDef _astmodule = {", 0)

self.emit(' PyModuleDef_HEAD_INIT, "_ast"', 0)

self.emit("};", 0)

self.emit("PyMODINIT_FUNC", 0)

self.emit("PyInit__ast(void)", 0)

self.emit("{", 0)

self.emit("PyObject *m, *d;", 1)

self.emit("if (!init_types()) return NULL;", 1)

self.emit('m = PyModule_Create(&_astmodule);', 1)

self.emit("if (!m) return NULL;", 1)