1#! /usr/bin/env python
2"""Generate C code from an ASDL description."""
3
4# TO DO
5# handle fields that have a type but no name
6
7import os, sys
8
9import asdl
10
11TABSIZE = 8
12MAX_COL = 80
13
14def get_c_type(name):
15    """Return a string for the C name of the type.
16
17    This function special cases the default types provided by asdl:
18    identifier, string, int, bool.
19    """
20    # XXX ack!  need to figure out where Id is useful and where string
21    if isinstance(name, asdl.Id):
22        name = name.value
23    if name in asdl.builtin_types:
24        return name
25    else:
26        return "%s_ty" % name
27
28def reflow_lines(s, depth):
29    """Reflow the line s indented depth tabs.
30
31    Return a sequence of lines where no line extends beyond MAX_COL
32    when properly indented.  The first line is properly indented based
33    exclusively on depth * TABSIZE.  All following lines -- these are
34    the reflowed lines generated by this function -- start at the same
35    column as the first character beyond the opening { in the first
36    line.
37    """
38    size = MAX_COL - depth * TABSIZE
39    if len(s) < size:
40        return [s]
41
42    lines = []
43    cur = s
44    padding = ""
45    while len(cur) > size:
46        i = cur.rfind(' ', 0, size)
47        # XXX this should be fixed for real
48        if i == -1 and 'GeneratorExp' in cur:
49            i = size + 3
50        assert i != -1, "Impossible line %d to reflow: %r" % (size, s)
51        lines.append(padding + cur[:i])
52        if len(lines) == 1:
53            # find new size based on brace
54            j = cur.find('{', 0, i)
55            if j >= 0:
56                j += 2 # account for the brace and the space after it
57                size -= j
58                padding = " " * j
59            else:
60                j = cur.find('(', 0, i)
61                if j >= 0:
62                    j += 1 # account for the paren (no space after it)
63                    size -= j
64                    padding = " " * j
65        cur = cur[i+1:]
66    else:
67        lines.append(padding + cur)
68    return lines
69
70def is_simple(sum):
71    """Return True if a sum is a simple.
72
73    A sum is simple if its types have no fields, e.g.
74    unaryop = Invert | Not | UAdd | USub
75    """
76    for t in sum.types:
77        if t.fields:
78            return False
79    return True
80
81
82class EmitVisitor(asdl.VisitorBase):
83    """Visit that emits lines"""
84
85    def __init__(self, file):
86        self.file = file
87        super(EmitVisitor, self).__init__()
88
89    def emit(self, s, depth, reflow=True):
90        # XXX reflow long lines?
91        if reflow:
92            lines = reflow_lines(s, depth)
93        else:
94            lines = [s]
95        for line in lines:
96            line = (" " * TABSIZE * depth) + line + "\n"
97            self.file.write(line)
98
99
100class TypeDefVisitor(EmitVisitor):
101    def visitModule(self, mod):
102        for dfn in mod.dfns:
103            self.visit(dfn)
104
105    def visitType(self, type, depth=0):
106        self.visit(type.value, type.name, depth)
107
108    def visitSum(self, sum, name, depth):
109        if is_simple(sum):
110            self.simple_sum(sum, name, depth)
111        else:
112            self.sum_with_constructors(sum, name, depth)
113
114    def simple_sum(self, sum, name, depth):
115        enum = []
116        for i in range(len(sum.types)):
117            type = sum.types[i]
118            enum.append("%s=%d" % (type.name, i + 1))
119        enums = ", ".join(enum)
120        ctype = get_c_type(name)
121        s = "typedef enum _%s { %s } %s;" % (name, enums, ctype)
122        self.emit(s, depth)
123        self.emit("", depth)
124
125    def sum_with_constructors(self, sum, name, depth):
126        ctype = get_c_type(name)
127        s = "typedef struct _%(name)s *%(ctype)s;" % locals()
128        self.emit(s, depth)
129        self.emit("", depth)
130
131    def visitProduct(self, product, name, depth):
132        ctype = get_c_type(name)
133        s = "typedef struct _%(name)s *%(ctype)s;" % locals()
134        self.emit(s, depth)
135        self.emit("", depth)
136
137
138class StructVisitor(EmitVisitor):
139    """Visitor to generate typedefs for AST."""
140
141    def visitModule(self, mod):
142        for dfn in mod.dfns:
143            self.visit(dfn)
144
145    def visitType(self, type, depth=0):
146        self.visit(type.value, type.name, depth)
147
148    def visitSum(self, sum, name, depth):
149        if not is_simple(sum):
150            self.sum_with_constructors(sum, name, depth)
151
152    def sum_with_constructors(self, sum, name, depth):
153        def emit(s, depth=depth):
154            self.emit(s % sys._getframe(1).f_locals, depth)
155        enum = []
156        for i in range(len(sum.types)):
157            type = sum.types[i]
158            enum.append("%s_kind=%d" % (type.name, i + 1))
159
160        emit("enum _%(name)s_kind {" + ", ".join(enum) + "};")
161
162        emit("struct _%(name)s {")
163        emit("enum _%(name)s_kind kind;", depth + 1)
164        emit("union {", depth + 1)
165        for t in sum.types:
166            self.visit(t, depth + 2)
167        emit("} v;", depth + 1)
168        for field in sum.attributes:
169            # rudimentary attribute handling
170            type = str(field.type)
171            assert type in asdl.builtin_types, type
172            emit("%s %s;" % (type, field.name), depth + 1);
173        emit("};")
174        emit("")
175
176    def visitConstructor(self, cons, depth):
177        if cons.fields:
178            self.emit("struct {", depth)
179            for f in cons.fields:
180                self.visit(f, depth + 1)
181            self.emit("} %s;" % cons.name, depth)
182            self.emit("", depth)
183        else:
184            # XXX not sure what I want here, nothing is probably fine
185            pass
186
187    def visitField(self, field, depth):
188        # XXX need to lookup field.type, because it might be something
189        # like a builtin...
190        ctype = get_c_type(field.type)
191        name = field.name
192        if field.seq:
193            if field.type.value in ('cmpop',):
194                self.emit("asdl_int_seq *%(name)s;" % locals(), depth)
195            else:
196                self.emit("asdl_seq *%(name)s;" % locals(), depth)
197        else:
198            self.emit("%(ctype)s %(name)s;" % locals(), depth)
199
200    def visitProduct(self, product, name, depth):
201        self.emit("struct _%(name)s {" % locals(), depth)
202        for f in product.fields:
203            self.visit(f, depth + 1)
204        self.emit("};", depth)
205        self.emit("", depth)
206
207
208class PrototypeVisitor(EmitVisitor):
209    """Generate function prototypes for the .h file"""
210
211    def visitModule(self, mod):
212        for dfn in mod.dfns:
213            self.visit(dfn)
214
215    def visitType(self, type):
216        self.visit(type.value, type.name)
217
218    def visitSum(self, sum, name):
219        if is_simple(sum):
220            pass # XXX
221        else:
222            for t in sum.types:
223                self.visit(t, name, sum.attributes)
224
225    def get_args(self, fields):
226        """Return list of C argument into, one for each field.
227
228        Argument info is 3-tuple of a C type, variable name, and flag
229        that is true if type can be NULL.
230        """
231        args = []
232        unnamed = {}
233        for f in fields:
234            if f.name is None:
235                name = f.type
236                c = unnamed[name] = unnamed.get(name, 0) + 1
237                if c > 1:
238                    name = "name%d" % (c - 1)
239            else:
240                name = f.name
241            # XXX should extend get_c_type() to handle this
242            if f.seq:
243                if f.type.value in ('cmpop',):
244                    ctype = "asdl_int_seq *"
245                else:
246                    ctype = "asdl_seq *"
247            else:
248                ctype = get_c_type(f.type)
249            args.append((ctype, name, f.opt or f.seq))
250        return args
251
252    def visitConstructor(self, cons, type, attrs):
253        args = self.get_args(cons.fields)
254        attrs = self.get_args(attrs)
255        ctype = get_c_type(type)
256        self.emit_function(cons.name, ctype, args, attrs)
257
258    def emit_function(self, name, ctype, args, attrs, union=True):
259        args = args + attrs
260        if args:
261            argstr = ", ".join(["%s %s" % (atype, aname)
262                                for atype, aname, opt in args])
263            argstr += ", PyArena *arena"
264        else:
265            argstr = "PyArena *arena"
266        margs = "a0"
267        for i in range(1, len(args)+1):
268            margs += ", a%d" % i
269        self.emit("#define %s(%s) _Py_%s(%s)" % (name, margs, name, margs), 0,
270                reflow=False)
271        self.emit("%s _Py_%s(%s);" % (ctype, name, argstr), False)
272
273    def visitProduct(self, prod, name):
274        self.emit_function(name, get_c_type(name),
275                           self.get_args(prod.fields), [], union=False)
276
277
278class FunctionVisitor(PrototypeVisitor):
279    """Visitor to generate constructor functions for AST."""
280
281    def emit_function(self, name, ctype, args, attrs, union=True):
282        def emit(s, depth=0, reflow=True):
283            self.emit(s, depth, reflow)
284        argstr = ", ".join(["%s %s" % (atype, aname)
285                            for atype, aname, opt in args + attrs])
286        if argstr:
287            argstr += ", PyArena *arena"
288        else:
289            argstr = "PyArena *arena"
290        self.emit("%s" % ctype, 0)
291        emit("%s(%s)" % (name, argstr))
292        emit("{")
293        emit("%s p;" % ctype, 1)
294        for argtype, argname, opt in args:
295            # XXX hack alert: false is allowed for a bool
296            if not opt and not (argtype == "bool" or argtype == "int"):
297                emit("if (!%s) {" % argname, 1)
298                emit("PyErr_SetString(PyExc_ValueError,", 2)
299                msg = "field %s is required for %s" % (argname, name)
300                emit('                "%s");' % msg,
301                     2, reflow=False)
302                emit('return NULL;', 2)
303                emit('}', 1)
304
305        emit("p = (%s)PyArena_Malloc(arena, sizeof(*p));" % ctype, 1);
306        emit("if (!p)", 1)
307        emit("return NULL;", 2)
308        if union:
309            self.emit_body_union(name, args, attrs)
310        else:
311            self.emit_body_struct(name, args, attrs)
312        emit("return p;", 1)
313        emit("}")
314        emit("")
315
316    def emit_body_union(self, name, args, attrs):
317        def emit(s, depth=0, reflow=True):
318            self.emit(s, depth, reflow)
319        emit("p->kind = %s_kind;" % name, 1)
320        for argtype, argname, opt in args:
321            emit("p->v.%s.%s = %s;" % (name, argname, argname), 1)
322        for argtype, argname, opt in attrs:
323            emit("p->%s = %s;" % (argname, argname), 1)
324
325    def emit_body_struct(self, name, args, attrs):
326        def emit(s, depth=0, reflow=True):
327            self.emit(s, depth, reflow)
328        for argtype, argname, opt in args:
329            emit("p->%s = %s;" % (argname, argname), 1)
330        assert not attrs
331
332
333class PickleVisitor(EmitVisitor):
334
335    def visitModule(self, mod):
336        for dfn in mod.dfns:
337            self.visit(dfn)
338
339    def visitType(self, type):
340        self.visit(type.value, type.name)
341
342    def visitSum(self, sum, name):
343        pass
344
345    def visitProduct(self, sum, name):
346        pass
347
348    def visitConstructor(self, cons, name):
349        pass
350
351    def visitField(self, sum):
352        pass
353
354
355class Obj2ModPrototypeVisitor(PickleVisitor):
356    def visitProduct(self, prod, name):
357        code = "static int obj2ast_%s(PyObject* obj, %s* out, PyArena* arena);"
358        self.emit(code % (name, get_c_type(name)), 0)
359
360    visitSum = visitProduct
361
362
363class Obj2ModVisitor(PickleVisitor):
364    def funcHeader(self, name):
365        ctype = get_c_type(name)
366        self.emit("int", 0)
367        self.emit("obj2ast_%s(PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
368        self.emit("{", 0)
369        self.emit("PyObject* tmp = NULL;", 1)
370        self.emit("int isinstance;", 1)
371        self.emit("", 0)
372
373    def sumTrailer(self, name):
374        self.emit("", 0)
375        self.emit("tmp = PyObject_Repr(obj);", 1)
376        # there's really nothing more we can do if this fails ...
377        self.emit("if (tmp == NULL) goto failed;", 1)
378        error = "expected some sort of %s, but got %%.400s" % name
379        format = "PyErr_Format(PyExc_TypeError, \"%s\", PyString_AS_STRING(tmp));"
380        self.emit(format % error, 1, reflow=False)
381        self.emit("failed:", 0)
382        self.emit("Py_XDECREF(tmp);", 1)
383        self.emit("return 1;", 1)
384        self.emit("}", 0)
385        self.emit("", 0)
386
387    def simpleSum(self, sum, name):
388        self.funcHeader(name)
389        for t in sum.types:
390            line = ("isinstance = PyObject_IsInstance(obj, "
391                    "(PyObject *)%s_type);")
392            self.emit(line % (t.name,), 1)
393            self.emit("if (isinstance == -1) {", 1)
394            self.emit("return 1;", 2)
395            self.emit("}", 1)
396            self.emit("if (isinstance) {", 1)
397            self.emit("*out = %s;" % t.name, 2)
398            self.emit("return 0;", 2)
399            self.emit("}", 1)
400        self.sumTrailer(name)
401
402    def buildArgs(self, fields):
403        return ", ".join(fields + ["arena"])
404
405    def complexSum(self, sum, name):
406        self.funcHeader(name)
407        for a in sum.attributes:
408            self.visitAttributeDeclaration(a, name, sum=sum)
409        self.emit("", 0)
410        # XXX: should we only do this for 'expr'?
411        self.emit("if (obj == Py_None) {", 1)
412        self.emit("*out = NULL;", 2)
413        self.emit("return 0;", 2)
414        self.emit("}", 1)
415        for a in sum.attributes:
416            self.visitField(a, name, sum=sum, depth=1)
417        for t in sum.types:
418            line = "isinstance = PyObject_IsInstance(obj, (PyObject*)%s_type);"
419            self.emit(line % (t.name,), 1)
420            self.emit("if (isinstance == -1) {", 1)
421            self.emit("return 1;", 2)
422            self.emit("}", 1)
423            self.emit("if (isinstance) {", 1)
424            for f in t.fields:
425                self.visitFieldDeclaration(f, t.name, sum=sum, depth=2)
426            self.emit("", 0)
427            for f in t.fields:
428                self.visitField(f, t.name, sum=sum, depth=2)
429            args = [f.name.value for f in t.fields] + [a.name.value for a in sum.attributes]
430            self.emit("*out = %s(%s);" % (t.name, self.buildArgs(args)), 2)
431            self.emit("if (*out == NULL) goto failed;", 2)
432            self.emit("return 0;", 2)
433            self.emit("}", 1)
434        self.sumTrailer(name)
435
436    def visitAttributeDeclaration(self, a, name, sum=sum):
437        ctype = get_c_type(a.type)
438        self.emit("%s %s;" % (ctype, a.name), 1)
439
440    def visitSum(self, sum, name):
441        if is_simple(sum):
442            self.simpleSum(sum, name)
443        else:
444            self.complexSum(sum, name)
445
446    def visitProduct(self, prod, name):
447        ctype = get_c_type(name)
448        self.emit("int", 0)
449        self.emit("obj2ast_%s(PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
450        self.emit("{", 0)
451        self.emit("PyObject* tmp = NULL;", 1)
452        for f in prod.fields:
453            self.visitFieldDeclaration(f, name, prod=prod, depth=1)
454        self.emit("", 0)
455        for f in prod.fields:
456            self.visitField(f, name, prod=prod, depth=1)
457        args = [f.name.value for f in prod.fields]
458        self.emit("*out = %s(%s);" % (name, self.buildArgs(args)), 1)
459        self.emit("return 0;", 1)
460        self.emit("failed:", 0)
461        self.emit("Py_XDECREF(tmp);", 1)
462        self.emit("return 1;", 1)
463        self.emit("}", 0)
464        self.emit("", 0)
465
466    def visitFieldDeclaration(self, field, name, sum=None, prod=None, depth=0):
467        ctype = get_c_type(field.type)
468        if field.seq:
469            if self.isSimpleType(field):
470                self.emit("asdl_int_seq* %s;" % field.name, depth)
471            else:
472                self.emit("asdl_seq* %s;" % field.name, depth)
473        else:
474            ctype = get_c_type(field.type)
475            self.emit("%s %s;" % (ctype, field.name), depth)
476
477    def isSimpleSum(self, field):
478        # XXX can the members of this list be determined automatically?
479        return field.type.value in ('expr_context', 'boolop', 'operator',
480                                    'unaryop', 'cmpop')
481
482    def isNumeric(self, field):
483        return get_c_type(field.type) in ("int", "bool")
484
485    def isSimpleType(self, field):
486        return self.isSimpleSum(field) or self.isNumeric(field)
487
488    def visitField(self, field, name, sum=None, prod=None, depth=0):
489        ctype = get_c_type(field.type)
490        self.emit("if (PyObject_HasAttrString(obj, \"%s\")) {" % field.name, depth)
491        self.emit("int res;", depth+1)
492        if field.seq:
493            self.emit("Py_ssize_t len;", depth+1)
494            self.emit("Py_ssize_t i;", depth+1)
495        self.emit("tmp = PyObject_GetAttrString(obj, \"%s\");" % field.name, depth+1)
496        self.emit("if (tmp == NULL) goto failed;", depth+1)
497        if field.seq:
498            self.emit("if (!PyList_Check(tmp)) {", depth+1)
499            self.emit("PyErr_Format(PyExc_TypeError, \"%s field \\\"%s\\\" must "
500                      "be a list, not a %%.200s\", tmp->ob_type->tp_name);" %
501                      (name, field.name),
502                      depth+2, reflow=False)
503            self.emit("goto failed;", depth+2)
504            self.emit("}", depth+1)
505            self.emit("len = PyList_GET_SIZE(tmp);", depth+1)
506            if self.isSimpleType(field):
507                self.emit("%s = asdl_int_seq_new(len, arena);" % field.name, depth+1)
508            else:
509                self.emit("%s = asdl_seq_new(len, arena);" % field.name, depth+1)
510            self.emit("if (%s == NULL) goto failed;" % field.name, depth+1)
511            self.emit("for (i = 0; i < len; i++) {", depth+1)
512            self.emit("%s value;" % ctype, depth+2)
513            self.emit("res = obj2ast_%s(PyList_GET_ITEM(tmp, i), &value, arena);" %
514                      field.type, depth+2, reflow=False)
515            self.emit("if (res != 0) goto failed;", depth+2)
516            self.emit("if (len != PyList_GET_SIZE(tmp)) {", depth+2)
517            self.emit("PyErr_SetString(PyExc_RuntimeError, \"%s field \\\"%s\\\" "
518                      "changed size during iteration\");" %
519                      (name, field.name),
520                      depth+3, reflow=False)
521            self.emit("goto failed;", depth+3)
522            self.emit("}", depth+2)
523            self.emit("asdl_seq_SET(%s, i, value);" % field.name, depth+2)
524            self.emit("}", depth+1)
525        else:
526            self.emit("res = obj2ast_%s(tmp, &%s, arena);" %
527                      (field.type, field.name), depth+1)
528            self.emit("if (res != 0) goto failed;", depth+1)
529
530        self.emit("Py_XDECREF(tmp);", depth+1)
531        self.emit("tmp = NULL;", depth+1)
532        self.emit("} else {", depth)
533        if not field.opt:
534            message = "required field \\\"%s\\\" missing from %s" % (field.name, name)
535            format = "PyErr_SetString(PyExc_TypeError, \"%s\");"
536            self.emit(format % message, depth+1, reflow=False)
537            self.emit("return 1;", depth+1)
538        else:
539            if self.isNumeric(field):
540                self.emit("%s = 0;" % field.name, depth+1)
541            elif not self.isSimpleType(field):
542                self.emit("%s = NULL;" % field.name, depth+1)
543            else:
544                raise TypeError("could not determine the default value for %s" % field.name)
545        self.emit("}", depth)
546
547
548class MarshalPrototypeVisitor(PickleVisitor):
549
550    def prototype(self, sum, name):
551        ctype = get_c_type(name)
552        self.emit("static int marshal_write_%s(PyObject **, int *, %s);"
553                  % (name, ctype), 0)
554
555    visitProduct = visitSum = prototype
556
557
558class PyTypesDeclareVisitor(PickleVisitor):
559
560    def visitProduct(self, prod, name):
561        self.emit("static PyTypeObject *%s_type;" % name, 0)
562        self.emit("static PyObject* ast2obj_%s(void*);" % name, 0)
563        if prod.fields:
564            self.emit("static char *%s_fields[]={" % name,0)
565            for f in prod.fields:
566                self.emit('"%s",' % f.name, 1)
567            self.emit("};", 0)
568
569    def visitSum(self, sum, name):
570        self.emit("static PyTypeObject *%s_type;" % name, 0)
571        if sum.attributes:
572            self.emit("static char *%s_attributes[] = {" % name, 0)
573            for a in sum.attributes:
574                self.emit('"%s",' % a.name, 1)
575            self.emit("};", 0)
576        ptype = "void*"
577        if is_simple(sum):
578            ptype = get_c_type(name)
579            tnames = []
580            for t in sum.types:
581                tnames.append(str(t.name)+"_singleton")
582            tnames = ", *".join(tnames)
583            self.emit("static PyObject *%s;" % tnames, 0)
584        self.emit("static PyObject* ast2obj_%s(%s);" % (name, ptype), 0)
585        for t in sum.types:
586            self.visitConstructor(t, name)
587
588    def visitConstructor(self, cons, name):
589        self.emit("static PyTypeObject *%s_type;" % cons.name, 0)
590        if cons.fields:
591            self.emit("static char *%s_fields[]={" % cons.name, 0)
592            for t in cons.fields:
593                self.emit('"%s",' % t.name, 1)
594            self.emit("};",0)
595
596class PyTypesVisitor(PickleVisitor):
597
598    def visitModule(self, mod):
599        self.emit("""
600static int
601ast_type_init(PyObject *self, PyObject *args, PyObject *kw)
602{
603    Py_ssize_t i, numfields = 0;
604    int res = -1;
605    PyObject *key, *value, *fields;
606    fields = PyObject_GetAttrString((PyObject*)Py_TYPE(self), "_fields");
607    if (!fields)
608        PyErr_Clear();
609    if (fields) {
610        numfields = PySequence_Size(fields);
611        if (numfields == -1)
612            goto cleanup;
613    }
614    res = 0; /* if no error occurs, this stays 0 to the end */
615    if (PyTuple_GET_SIZE(args) > 0) {
616        if (numfields != PyTuple_GET_SIZE(args)) {
617            PyErr_Format(PyExc_TypeError, "%.400s constructor takes %s"
618                         "%zd positional argument%s",
619                         Py_TYPE(self)->tp_name,
620                         numfields == 0 ? "" : "either 0 or ",
621                         numfields, numfields == 1 ? "" : "s");
622            res = -1;
623            goto cleanup;
624        }
625        for (i = 0; i < PyTuple_GET_SIZE(args); i++) {
626            /* cannot be reached when fields is NULL */
627            PyObject *name = PySequence_GetItem(fields, i);
628            if (!name) {
629                res = -1;
630                goto cleanup;
631            }
632            res = PyObject_SetAttr(self, name, PyTuple_GET_ITEM(args, i));
633            Py_DECREF(name);
634            if (res < 0)
635                goto cleanup;
636        }
637    }
638    if (kw) {
639        i = 0;  /* needed by PyDict_Next */
640        while (PyDict_Next(kw, &i, &key, &value)) {
641            res = PyObject_SetAttr(self, key, value);
642            if (res < 0)
643                goto cleanup;
644        }
645    }
646  cleanup:
647    Py_XDECREF(fields);
648    return res;
649}
650
651/* Pickling support */
652static PyObject *
653ast_type_reduce(PyObject *self, PyObject *unused)
654{
655    PyObject *res;
656    PyObject *dict = PyObject_GetAttrString(self, "__dict__");
657    if (dict == NULL) {
658        if (PyErr_ExceptionMatches(PyExc_AttributeError))
659            PyErr_Clear();
660        else
661            return NULL;
662    }
663    if (dict) {
664        res = Py_BuildValue("O()O", Py_TYPE(self), dict);
665        Py_DECREF(dict);
666        return res;
667    }
668    return Py_BuildValue("O()", Py_TYPE(self));
669}
670
671static PyMethodDef ast_type_methods[] = {
672    {"__reduce__", ast_type_reduce, METH_NOARGS, NULL},
673    {NULL}
674};
675
676static PyTypeObject AST_type = {
677    PyVarObject_HEAD_INIT(&PyType_Type, 0)
678    "_ast.AST",
679    sizeof(PyObject),
680    0,
681    0,                       /* tp_dealloc */
682    0,                       /* tp_print */
683    0,                       /* tp_getattr */
684    0,                       /* tp_setattr */
685    0,                       /* tp_compare */
686    0,                       /* tp_repr */
687    0,                       /* tp_as_number */
688    0,                       /* tp_as_sequence */
689    0,                       /* tp_as_mapping */
690    0,                       /* tp_hash */
691    0,                       /* tp_call */
692    0,                       /* tp_str */
693    PyObject_GenericGetAttr, /* tp_getattro */
694    PyObject_GenericSetAttr, /* tp_setattro */
695    0,                       /* tp_as_buffer */
696    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
697    0,                       /* tp_doc */
698    0,                       /* tp_traverse */
699    0,                       /* tp_clear */
700    0,                       /* tp_richcompare */
701    0,                       /* tp_weaklistoffset */
702    0,                       /* tp_iter */
703    0,                       /* tp_iternext */
704    ast_type_methods,        /* tp_methods */
705    0,                       /* tp_members */
706    0,                       /* tp_getset */
707    0,                       /* tp_base */
708    0,                       /* tp_dict */
709    0,                       /* tp_descr_get */
710    0,                       /* tp_descr_set */
711    0,                       /* tp_dictoffset */
712    (initproc)ast_type_init, /* tp_init */
713    PyType_GenericAlloc,     /* tp_alloc */
714    PyType_GenericNew,       /* tp_new */
715    PyObject_Del,            /* tp_free */
716};
717
718
719static PyTypeObject* make_type(char *type, PyTypeObject* base, char**fields, int num_fields)
720{
721    PyObject *fnames, *result;
722    int i;
723    fnames = PyTuple_New(num_fields);
724    if (!fnames) return NULL;
725    for (i = 0; i < num_fields; i++) {
726        PyObject *field = PyString_FromString(fields[i]);
727        if (!field) {
728            Py_DECREF(fnames);
729            return NULL;
730        }
731        PyTuple_SET_ITEM(fnames, i, field);
732    }
733    result = PyObject_CallFunction((PyObject*)&PyType_Type, "s(O){sOss}",
734                    type, base, "_fields", fnames, "__module__", "_ast");
735    Py_DECREF(fnames);
736    return (PyTypeObject*)result;
737}
738
739static int add_attributes(PyTypeObject* type, char**attrs, int num_fields)
740{
741    int i, result;
742    PyObject *s, *l = PyTuple_New(num_fields);
743    if (!l)
744        return 0;
745    for (i = 0; i < num_fields; i++) {
746        s = PyString_FromString(attrs[i]);
747        if (!s) {
748            Py_DECREF(l);
749            return 0;
750        }
751        PyTuple_SET_ITEM(l, i, s);
752    }
753    result = PyObject_SetAttrString((PyObject*)type, "_attributes", l) >= 0;
754    Py_DECREF(l);
755    return result;
756}
757
758/* Conversion AST -> Python */
759
760static PyObject* ast2obj_list(asdl_seq *seq, PyObject* (*func)(void*))
761{
762    int i, n = asdl_seq_LEN(seq);
763    PyObject *result = PyList_New(n);
764    PyObject *value;
765    if (!result)
766        return NULL;
767    for (i = 0; i < n; i++) {
768        value = func(asdl_seq_GET(seq, i));
769        if (!value) {
770            Py_DECREF(result);
771            return NULL;
772        }
773        PyList_SET_ITEM(result, i, value);
774    }
775    return result;
776}
777
778static PyObject* ast2obj_object(void *o)
779{
780    if (!o)
781        o = Py_None;
782    Py_INCREF((PyObject*)o);
783    return (PyObject*)o;
784}
785#define ast2obj_identifier ast2obj_object
786#define ast2obj_string ast2obj_object
787static PyObject* ast2obj_bool(bool b)
788{
789    return PyBool_FromLong(b);
790}
791
792static PyObject* ast2obj_int(long b)
793{
794    return PyInt_FromLong(b);
795}
796
797/* Conversion Python -> AST */
798
799static int obj2ast_object(PyObject* obj, PyObject** out, PyArena* arena)
800{
801    if (obj == Py_None)
802        obj = NULL;
803    if (obj)
804        PyArena_AddPyObject(arena, obj);
805    Py_XINCREF(obj);
806    *out = obj;
807    return 0;
808}
809
810static int obj2ast_identifier(PyObject* obj, PyObject** out, PyArena* arena)
811{
812    if (!PyString_CheckExact(obj) && obj != Py_None) {
813        PyErr_Format(PyExc_TypeError,
814                    "AST identifier must be of type str");
815        return 1;
816    }
817    return obj2ast_object(obj, out, arena);
818}
819
820static int obj2ast_string(PyObject* obj, PyObject** out, PyArena* arena)
821{
822    if (!PyString_CheckExact(obj) && !PyUnicode_CheckExact(obj)) {
823        PyErr_SetString(PyExc_TypeError,
824                       "AST string must be of type str or unicode");
825        return 1;
826    }
827    return obj2ast_object(obj, out, arena);
828}
829
830static int obj2ast_int(PyObject* obj, int* out, PyArena* arena)
831{
832    int i;
833    if (!PyInt_Check(obj) && !PyLong_Check(obj)) {
834        PyObject *s = PyObject_Repr(obj);
835        if (s == NULL) return 1;
836        PyErr_Format(PyExc_ValueError, "invalid integer value: %.400s",
837                     PyString_AS_STRING(s));
838        Py_DECREF(s);
839        return 1;
840    }
841
842    i = (int)PyLong_AsLong(obj);
843    if (i == -1 && PyErr_Occurred())
844        return 1;
845    *out = i;
846    return 0;
847}
848
849static int obj2ast_bool(PyObject* obj, bool* out, PyArena* arena)
850{
851    if (!PyBool_Check(obj)) {
852        PyObject *s = PyObject_Repr(obj);
853        if (s == NULL) return 1;
854        PyErr_Format(PyExc_ValueError, "invalid boolean value: %.400s",
855                     PyString_AS_STRING(s));
856        Py_DECREF(s);
857        return 1;
858    }
859
860    *out = (obj == Py_True);
861    return 0;
862}
863
864static int add_ast_fields(void)
865{
866    PyObject *empty_tuple, *d;
867    if (PyType_Ready(&AST_type) < 0)
868        return -1;
869    d = AST_type.tp_dict;
870    empty_tuple = PyTuple_New(0);
871    if (!empty_tuple ||
872        PyDict_SetItemString(d, "_fields", empty_tuple) < 0 ||
873        PyDict_SetItemString(d, "_attributes", empty_tuple) < 0) {
874        Py_XDECREF(empty_tuple);
875        return -1;
876    }
877    Py_DECREF(empty_tuple);
878    return 0;
879}
880
881""", 0, reflow=False)
882
883        self.emit("static int init_types(void)",0)
884        self.emit("{", 0)
885        self.emit("static int initialized;", 1)
886        self.emit("if (initialized) return 1;", 1)
887        self.emit("if (add_ast_fields() < 0) return 0;", 1)
888        for dfn in mod.dfns:
889            self.visit(dfn)
890        self.emit("initialized = 1;", 1)
891        self.emit("return 1;", 1);
892        self.emit("}", 0)
893
894    def visitProduct(self, prod, name):
895        if prod.fields:
896            fields = name.value+"_fields"
897        else:
898            fields = "NULL"
899        self.emit('%s_type = make_type("%s", &AST_type, %s, %d);' %
900                        (name, name, fields, len(prod.fields)), 1)
901        self.emit("if (!%s_type) return 0;" % name, 1)
902
903    def visitSum(self, sum, name):
904        self.emit('%s_type = make_type("%s", &AST_type, NULL, 0);' %
905                  (name, name), 1)
906        self.emit("if (!%s_type) return 0;" % name, 1)
907        if sum.attributes:
908            self.emit("if (!add_attributes(%s_type, %s_attributes, %d)) return 0;" %
909                            (name, name, len(sum.attributes)), 1)
910        else:
911            self.emit("if (!add_attributes(%s_type, NULL, 0)) return 0;" % name, 1)
912        simple = is_simple(sum)
913        for t in sum.types:
914            self.visitConstructor(t, name, simple)
915
916    def visitConstructor(self, cons, name, simple):
917        if cons.fields:
918            fields = cons.name.value+"_fields"
919        else:
920            fields = "NULL"
921        self.emit('%s_type = make_type("%s", %s_type, %s, %d);' %
922                            (cons.name, cons.name, name, fields, len(cons.fields)), 1)
923        self.emit("if (!%s_type) return 0;" % cons.name, 1)
924        if simple:
925            self.emit("%s_singleton = PyType_GenericNew(%s_type, NULL, NULL);" %
926                             (cons.name, cons.name), 1)
927            self.emit("if (!%s_singleton) return 0;" % cons.name, 1)
928
929
930class ASTModuleVisitor(PickleVisitor):
931
932    def visitModule(self, mod):
933        self.emit("PyMODINIT_FUNC", 0)
934        self.emit("init_ast(void)", 0)
935        self.emit("{", 0)
936        self.emit("PyObject *m, *d;", 1)
937        self.emit("if (!init_types()) return;", 1)
938        self.emit('m = Py_InitModule3("_ast", NULL, NULL);', 1)
939        self.emit("if (!m) return;", 1)
940        self.emit("d = PyModule_GetDict(m);", 1)
941        self.emit('if (PyDict_SetItemString(d, "AST", (PyObject*)&AST_type) < 0) return;', 1)
942        self.emit('if (PyModule_AddIntConstant(m, "PyCF_ONLY_AST", PyCF_ONLY_AST) < 0)', 1)
943        self.emit("return;", 2)
944        # Value of version: "$Revision$"
945        self.emit('if (PyModule_AddStringConstant(m, "__version__", "%s") < 0)'
946                % mod.version, 1)
947        self.emit("return;", 2)
948        for dfn in mod.dfns:
949            self.visit(dfn)
950        self.emit("}", 0)
951
952    def visitProduct(self, prod, name):
953        self.addObj(name)
954
955    def visitSum(self, sum, name):
956        self.addObj(name)
957        for t in sum.types:
958            self.visitConstructor(t, name)
959
960    def visitConstructor(self, cons, name):
961        self.addObj(cons.name)
962
963    def addObj(self, name):
964        self.emit('if (PyDict_SetItemString(d, "%s", (PyObject*)%s_type) < 0) return;' % (name, name), 1)
965
966
967_SPECIALIZED_SEQUENCES = ('stmt', 'expr')
968
969def find_sequence(fields, doing_specialization):
970    """Return True if any field uses a sequence."""
971    for f in fields:
972        if f.seq:
973            if not doing_specialization:
974                return True
975            if str(f.type) not in _SPECIALIZED_SEQUENCES:
976                return True
977    return False
978
979def has_sequence(types, doing_specialization):
980    for t in types:
981        if find_sequence(t.fields, doing_specialization):
982            return True
983    return False
984
985
986class StaticVisitor(PickleVisitor):
987    CODE = '''Very simple, always emit this static code.  Override CODE'''
988
989    def visit(self, object):
990        self.emit(self.CODE, 0, reflow=False)
991
992
993class ObjVisitor(PickleVisitor):
994
995    def func_begin(self, name):
996        ctype = get_c_type(name)
997        self.emit("PyObject*", 0)
998        self.emit("ast2obj_%s(void* _o)" % (name), 0)
999        self.emit("{", 0)
1000        self.emit("%s o = (%s)_o;" % (ctype, ctype), 1)
1001        self.emit("PyObject *result = NULL, *value = NULL;", 1)
1002        self.emit('if (!o) {', 1)
1003        self.emit("Py_INCREF(Py_None);", 2)
1004        self.emit('return Py_None;', 2)
1005        self.emit("}", 1)
1006        self.emit('', 0)
1007
1008    def func_end(self):
1009        self.emit("return result;", 1)
1010        self.emit("failed:", 0)
1011        self.emit("Py_XDECREF(value);", 1)
1012        self.emit("Py_XDECREF(result);", 1)
1013        self.emit("return NULL;", 1)
1014        self.emit("}", 0)
1015        self.emit("", 0)
1016
1017    def visitSum(self, sum, name):
1018        if is_simple(sum):
1019            self.simpleSum(sum, name)
1020            return
1021        self.func_begin(name)
1022        self.emit("switch (o->kind) {", 1)
1023        for i in range(len(sum.types)):
1024            t = sum.types[i]
1025            self.visitConstructor(t, i + 1, name)
1026        self.emit("}", 1)
1027        for a in sum.attributes:
1028            self.emit("value = ast2obj_%s(o->%s);" % (a.type, a.name), 1)
1029            self.emit("if (!value) goto failed;", 1)
1030            self.emit('if (PyObject_SetAttrString(result, "%s", value) < 0)' % a.name, 1)
1031            self.emit('goto failed;', 2)
1032            self.emit('Py_DECREF(value);', 1)
1033        self.func_end()
1034
1035    def simpleSum(self, sum, name):
1036        self.emit("PyObject* ast2obj_%s(%s_ty o)" % (name, name), 0)
1037        self.emit("{", 0)
1038        self.emit("switch(o) {", 1)
1039        for t in sum.types:
1040            self.emit("case %s:" % t.name, 2)
1041            self.emit("Py_INCREF(%s_singleton);" % t.name, 3)
1042            self.emit("return %s_singleton;" % t.name, 3)
1043        self.emit("default:", 2)
1044        self.emit('/* should never happen, but just in case ... */', 3)
1045        code = "PyErr_Format(PyExc_SystemError, \"unknown %s found\");" % name
1046        self.emit(code, 3, reflow=False)
1047        self.emit("return NULL;", 3)
1048        self.emit("}", 1)
1049        self.emit("}", 0)
1050
1051    def visitProduct(self, prod, name):
1052        self.func_begin(name)
1053        self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % name, 1);
1054        self.emit("if (!result) return NULL;", 1)
1055        for field in prod.fields:
1056            self.visitField(field, name, 1, True)
1057        self.func_end()
1058
1059    def visitConstructor(self, cons, enum, name):
1060        self.emit("case %s_kind:" % cons.name, 1)
1061        self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % cons.name, 2);
1062        self.emit("if (!result) goto failed;", 2)
1063        for f in cons.fields:
1064            self.visitField(f, cons.name, 2, False)
1065        self.emit("break;", 2)
1066
1067    def visitField(self, field, name, depth, product):
1068        def emit(s, d):
1069            self.emit(s, depth + d)
1070        if product:
1071            value = "o->%s" % field.name
1072        else:
1073            value = "o->v.%s.%s" % (name, field.name)
1074        self.set(field, value, depth)
1075        emit("if (!value) goto failed;", 0)
1076        emit('if (PyObject_SetAttrString(result, "%s", value) == -1)' % field.name, 0)
1077        emit("goto failed;", 1)
1078        emit("Py_DECREF(value);", 0)
1079
1080    def emitSeq(self, field, value, depth, emit):
1081        emit("seq = %s;" % value, 0)
1082        emit("n = asdl_seq_LEN(seq);", 0)
1083        emit("value = PyList_New(n);", 0)
1084        emit("if (!value) goto failed;", 0)
1085        emit("for (i = 0; i < n; i++) {", 0)
1086        self.set("value", field, "asdl_seq_GET(seq, i)", depth + 1)
1087        emit("if (!value1) goto failed;", 1)
1088        emit("PyList_SET_ITEM(value, i, value1);", 1)
1089        emit("value1 = NULL;", 1)
1090        emit("}", 0)
1091
1092    def set(self, field, value, depth):
1093        if field.seq:
1094            # XXX should really check for is_simple, but that requires a symbol table
1095            if field.type.value == "cmpop":
1096                # While the sequence elements are stored as void*,
1097                # ast2obj_cmpop expects an enum
1098                self.emit("{", depth)
1099                self.emit("int i, n = asdl_seq_LEN(%s);" % value, depth+1)
1100                self.emit("value = PyList_New(n);", depth+1)
1101                self.emit("if (!value) goto failed;", depth+1)
1102                self.emit("for(i = 0; i < n; i++)", depth+1)
1103                # This cannot fail, so no need for error handling
1104                self.emit("PyList_SET_ITEM(value, i, ast2obj_cmpop((cmpop_ty)asdl_seq_GET(%s, i)));" % value,
1105                          depth+2, reflow=False)
1106                self.emit("}", depth)
1107            else:
1108                self.emit("value = ast2obj_list(%s, ast2obj_%s);" % (value, field.type), depth)
1109        else:
1110            ctype = get_c_type(field.type)
1111            self.emit("value = ast2obj_%s(%s);" % (field.type, value), depth, reflow=False)
1112
1113
1114class PartingShots(StaticVisitor):
1115
1116    CODE = """
1117PyObject* PyAST_mod2obj(mod_ty t)
1118{
1119    init_types();
1120    return ast2obj_mod(t);
1121}
1122
1123/* mode is 0 for "exec", 1 for "eval" and 2 for "single" input */
1124mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode)
1125{
1126    mod_ty res;
1127    PyObject *req_type[3];
1128    char *req_name[3];
1129    int isinstance;
1130
1131    req_type[0] = (PyObject*)Module_type;
1132    req_type[1] = (PyObject*)Expression_type;
1133    req_type[2] = (PyObject*)Interactive_type;
1134
1135    req_name[0] = "Module";
1136    req_name[1] = "Expression";
1137    req_name[2] = "Interactive";
1138
1139    assert(0 <= mode && mode <= 2);
1140
1141    init_types();
1142
1143    isinstance = PyObject_IsInstance(ast, req_type[mode]);
1144    if (isinstance == -1)
1145        return NULL;
1146    if (!isinstance) {
1147        PyErr_Format(PyExc_TypeError, "expected %s node, got %.400s",
1148                     req_name[mode], Py_TYPE(ast)->tp_name);
1149        return NULL;
1150    }
1151    if (obj2ast_mod(ast, &res, arena) != 0)
1152        return NULL;
1153    else
1154        return res;
1155}
1156
1157int PyAST_Check(PyObject* obj)
1158{
1159    init_types();
1160    return PyObject_IsInstance(obj, (PyObject*)&AST_type);
1161}
1162"""
1163
1164class ChainOfVisitors:
1165    def __init__(self, *visitors):
1166        self.visitors = visitors
1167
1168    def visit(self, object):
1169        for v in self.visitors:
1170            v.visit(object)
1171            v.emit("", 0)
1172
1173common_msg = "/* File automatically generated by %s. */\n\n"
1174
1175c_file_msg = """
1176/*
1177   __version__ %s.
1178
1179   This module must be committed separately after each AST grammar change;
1180   The __version__ number is set to the revision number of the commit
1181   containing the grammar change.
1182*/
1183
1184"""
1185
1186def main(srcfile):
1187    argv0 = sys.argv[0]
1188    components = argv0.split(os.sep)
1189    argv0 = os.sep.join(components[-2:])
1190    auto_gen_msg = common_msg % argv0
1191    mod = asdl.parse(srcfile)
1192    mod.version = "82160"
1193    if not asdl.check(mod):
1194        sys.exit(1)
1195    if INC_DIR:
1196        p = "%s/%s-ast.h" % (INC_DIR, mod.name)
1197        f = open(p, "wb")
1198        f.write(auto_gen_msg)
1199        f.write('#include "asdl.h"\n\n')
1200        c = ChainOfVisitors(TypeDefVisitor(f),
1201                            StructVisitor(f),
1202                            PrototypeVisitor(f),
1203                            )
1204        c.visit(mod)
1205        f.write("PyObject* PyAST_mod2obj(mod_ty t);\n")
1206        f.write("mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode);\n")
1207        f.write("int PyAST_Check(PyObject* obj);\n")
1208        f.close()
1209
1210    if SRC_DIR:
1211        p = os.path.join(SRC_DIR, str(mod.name) + "-ast.c")
1212        f = open(p, "wb")
1213        f.write(auto_gen_msg)
1214        f.write(c_file_msg % mod.version)
1215        f.write('#include "Python.h"\n')
1216        f.write('#include "%s-ast.h"\n' % mod.name)
1217        f.write('\n')
1218        f.write("static PyTypeObject AST_type;\n")
1219        v = ChainOfVisitors(
1220            PyTypesDeclareVisitor(f),
1221            PyTypesVisitor(f),
1222            Obj2ModPrototypeVisitor(f),
1223            FunctionVisitor(f),
1224            ObjVisitor(f),
1225            Obj2ModVisitor(f),
1226            ASTModuleVisitor(f),
1227            PartingShots(f),
1228            )
1229        v.visit(mod)
1230        f.close()
1231
1232if __name__ == "__main__":
1233    import sys
1234    import getopt
1235
1236    INC_DIR = ''
1237    SRC_DIR = ''
1238    opts, args = getopt.getopt(sys.argv[1:], "h:c:")
1239    if len(opts) != 1:
1240        print "Must specify exactly one output file"
1241        sys.exit(1)
1242    for o, v in opts:
1243        if o == '-h':
1244            INC_DIR = v
1245        if o == '-c':
1246            SRC_DIR = v
1247    if len(args) != 1:
1248        print "Must specify single input file"
1249        sys.exit(1)
1250    main(args[0])
1251