#! /usr/bin/env python
"""Generate C code from an ASDL description."""
# TO DO
# handle fields that have a type but no name
import os, sys
import asdl
TABSIZE = 8
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:
identifier, string, int.
"""
# XXX ack! need to figure out where Id is useful and where string
if isinstance(name, asdl.Id):
name = name.value
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
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:
line = (" " * TABSIZE * depth) + line + "\n"
self.file.write(line)
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 typdefs 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)
else:
# XXX not sure what I want here, nothing is probably fine
pass
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.value in ('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)
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.value in ('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), [], 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)
assert not attrs
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("PyObject* tmp = NULL;", 1)
self.emit("int isinstance;", 1)
self.emit("", 0)
def sumTrailer(self, name):
self.emit("", 0)
self.emit("tmp = PyObject_Repr(obj);", 1)
# there's really nothing more we can do if this fails ...
self.emit("if (tmp == NULL) goto failed;", 1)
error = "expected some sort of %s, but got %%.400s" % name
format = "PyErr_Format(PyExc_TypeError, \"%s\", PyBytes_AS_STRING(tmp));"
self.emit(format % error, 1, reflow=False)
self.emit("failed:", 0)
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)
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.value for f in t.fields] + [a.name.value 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)
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)
self.emit("", 0)
for f in prod.fields:
self.visitField(f, name, prod=prod, depth=1)
args = [f.name.value for f in prod.fields]
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.value 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_HasAttrString(obj, \"%s\")) {" % field.name, 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("tmp = PyObject_GetAttrString(obj, \"%s\");" % field.name, depth+1)
self.emit("if (tmp == NULL) goto failed;", depth+1)
if field.seq:
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 = asdl_int_seq_new(len, arena);" % field.name, depth+1)
else:
self.emit("%s = 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 value;" % ctype, depth+2)
self.emit("res = obj2ast_%s(PyList_GET_ITEM(tmp, i), &value, arena);" %
field.type, depth+2, reflow=False)
self.emit("if (res != 0) goto failed;", depth+2)
self.emit("asdl_seq_SET(%s, i, value);" % 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_XDECREF(tmp);", depth+1)
self.emit("tmp = NULL;", depth+1)
self.emit("} else {", depth)
if not field.opt:
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:
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)
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.fields:
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:
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:
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("""
static int
ast_type_init(PyObject *self, PyObject *args, PyObject *kw)
{
Py_ssize_t i, numfields = 0;
int res = -1;
PyObject *key, *value, *fields;
fields = PyObject_GetAttrString((PyObject*)Py_TYPE(self), "_fields");
if (!fields)
PyErr_Clear();
if (fields) {
numfields = PySequence_Size(fields);
if (numfields == -1)
goto cleanup;
}
res = 0; /* if no error occurs, this stays 0 to the end */
if (PyTuple_GET_SIZE(args) > 0) {
if (numfields != PyTuple_GET_SIZE(args)) {
PyErr_Format(PyExc_TypeError, "%.400s constructor takes %s"
"%zd positional argument%s",
Py_TYPE(self)->tp_name,
numfields == 0 ? "" : "either 0 or ",
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)
{
PyObject *res;
PyObject *dict = PyObject_GetAttrString(self, "__dict__");
if (dict == NULL) {
if (PyErr_ExceptionMatches(PyExc_AttributeError))
PyErr_Clear();
else
return NULL;
}
if (dict) {
res = Py_BuildValue("O()O", Py_TYPE(self), dict);
Py_DECREF(dict);
return res;
}
return Py_BuildValue("O()", Py_TYPE(self));
}
static PyMethodDef ast_type_methods[] = {
{"__reduce__", ast_type_reduce, METH_NOARGS, NULL},
{NULL}
};
static PyTypeObject AST_type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"_ast.AST",
sizeof(PyObject),
0,
0, /* 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, /* tp_flags */
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
ast_type_methods, /* tp_methods */
0, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
(initproc)ast_type_init, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
PyType_GenericNew, /* tp_new */
PyObject_Del, /* tp_free */
};
static PyTypeObject* make_type(char *type, PyTypeObject* base, char**fields, int num_fields)
{
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, "U(O){sOss}",
type, base, "_fields", fnames, "__module__", "_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_SetAttrString((PyObject*)type, "_attributes", l) >= 0;
Py_DECREF(l);
return result;
}
/* Conversion AST -> Python */
static PyObject* ast2obj_list(asdl_seq *seq, PyObject* (*func)(void*))
{
int 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_identifier ast2obj_object
#define ast2obj_string 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)
PyArena_AddPyObject(arena, obj);
Py_XINCREF(obj);
*out = obj;
return 0;
}
#define obj2ast_identifier obj2ast_object
#define obj2ast_string obj2ast_object
static int obj2ast_int(PyObject* obj, int* out, PyArena* arena)
{
int i;
if (!PyLong_Check(obj)) {
PyObject *s = PyObject_Repr(obj);
if (s == NULL) return 1;
PyErr_Format(PyExc_ValueError, "invalid integer value: %.400s",
PyBytes_AS_STRING(s));
Py_DECREF(s);
return 1;
}
i = (int)PyLong_AsLong(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_SetItemString(d, "_fields", empty_tuple) < 0 ||
PyDict_SetItemString(d, "_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.value+"_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)
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.value+"_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)
def parse_version(mod):
return mod.version.value[12:-3]
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)
self.emit("d = PyModule_GetDict(m);", 1)
self.emit('if (PyDict_SetItemString(d, "AST", (PyObject*)&AST_type) < 0) return NULL;', 1)
self.emit('if (PyModule_AddIntConstant(m, "PyCF_ONLY_AST", PyCF_ONLY_AST) < 0)', 1)
self.emit("return NULL;", 2)
# Value of version: "$Revision: 76778 $"
self.emit('if (PyModule_AddStringConstant(m, "__version__", "%s") < 0)'
% parse_version(mod), 1)
self.emit("return NULL;", 2)
for dfn in mod.dfns:
self.visit(dfn)
self.emit("return m;", 1)
self.emit("}", 0)
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 (PyDict_SetItemString(d, "%s", (PyObject*)%s_type) < 0) return NULL;' % (name, 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. Overide 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(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('if (!o) {', 1)
self.emit("Py_INCREF(Py_None);", 2)
self.emit('return Py_None;', 2)
self.emit("}", 1)
self.emit('', 0)
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(o->%s);" % (a.type, a.name), 1)
self.emit("if (!value) goto failed;", 1)
self.emit('if (PyObject_SetAttrString(result, "%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(%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(%s_singleton);" % t.name, 3)
self.emit("return %s_singleton;" % t.name, 3)
self.emit("default:" % name, 2)
self.emit('/* should never happen, but just in case ... */', 3)
code = "PyErr_Format(PyExc_SystemError, \"unknown %s found\");" % name
self.emit(code, 3, reflow=False)
self.emit("return NULL;", 3)
self.emit("}", 1)
self.emit("}", 0)
def visitProduct(self, prod, name):
self.func_begin(name)
self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % name, 1);
self.emit("if (!result) return NULL;", 1)
for field in prod.fields:
self.visitField(field, name, 1, True)
self.func_end()
def visitConstructor(self, cons, enum, name):
self.emit("case %s_kind:" % cons.name, 1)
self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % cons.name, 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_SetAttrString(result, "%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.value == "cmpop":
# While the sequence elements are stored as void*,
# ast2obj_cmpop expects an enum
self.emit("{", depth)
self.emit("int 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((cmpop_ty)asdl_seq_GET(%s, i)));" % value,
depth+2, reflow=False)
self.emit("}", depth)
else:
self.emit("value = ast2obj_list(%s, ast2obj_%s);" % (value, field.type), depth)
else:
ctype = get_c_type(field.type)
self.emit("value = ast2obj_%s(%s);" % (field.type, value), depth, reflow=False)
class PartingShots(StaticVisitor):
CODE = """
PyObject* PyAST_mod2obj(mod_ty t)
{
init_types();
return ast2obj_mod(t);
}
/* mode is 0 for "exec", 1 for "eval" and 2 for "single" input */
mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode)
{
mod_ty res;
PyObject *req_type[] = {(PyObject*)Module_type, (PyObject*)Expression_type,
(PyObject*)Interactive_type};
char *req_name[] = {"Module", "Expression", "Interactive"};
int isinstance;
assert(0 <= mode && mode <= 2);
init_types();
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], Py_TYPE(ast)->tp_name);
return NULL;
}
if (obj2ast_mod(ast, &res, arena) != 0)
return NULL;
else
return res;
}
int PyAST_Check(PyObject* obj)
{
init_types();
return PyObject_IsInstance(obj, (PyObject*)&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)
common_msg = "/* File automatically generated by %s. */\n\n"
c_file_msg = """
/*
__version__ %s.
This module must be committed separately after each AST grammar change;
The __version__ number is set to the revision number of the commit
containing the grammar change.
*/
"""
def main(srcfile):
argv0 = sys.argv[0]
components = argv0.split(os.sep)
argv0 = os.sep.join(components[-2:])
auto_gen_msg = common_msg % argv0
mod = asdl.parse(srcfile)
if not asdl.check(mod):
sys.exit(1)
if INC_DIR:
p = "%s/%s-ast.h" % (INC_DIR, mod.name)
f = open(p, "w")
f.write(auto_gen_msg)
f.write('#include "asdl.h"\n\n')
c = ChainOfVisitors(TypeDefVisitor(f),
StructVisitor(f),
PrototypeVisitor(f),
)
c.visit(mod)
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.close()
if SRC_DIR:
p = os.path.join(SRC_DIR, str(mod.name) + "-ast.c")
f = open(p, "w")
f.write(auto_gen_msg)
f.write(c_file_msg % parse_version(mod))
f.write('#include "Python.h"\n')
f.write('#include "%s-ast.h"\n' % mod.name)
f.write('\n')
f.write("static PyTypeObject AST_type;\n")
v = ChainOfVisitors(
PyTypesDeclareVisitor(f),
PyTypesVisitor(f),
Obj2ModPrototypeVisitor(f),
FunctionVisitor(f),
ObjVisitor(f),
Obj2ModVisitor(f),
ASTModuleVisitor(f),
PartingShots(f),
)
v.visit(mod)
f.close()
if __name__ == "__main__":
import sys
import getopt
INC_DIR = ''
SRC_DIR = ''
opts, args = getopt.getopt(sys.argv[1:], "h:c:")
if len(opts) != 1:
sys.stdout.write("Must specify exactly one output file\n")
sys.exit(1)
for o, v in opts:
if o == '-h':
INC_DIR = v
if o == '-c':
SRC_DIR = v
if len(args) != 1:
sys.stdout.write("Must specify single input file\n")
sys.exit(1)
main(args[0])
|