Files
flatpak/variant-parse.py
2020-01-08 20:18:29 +01:00

424 lines
13 KiB
Python
Executable File

#!/bin/env python3
import sys
import os
from pyparsing import *
from pyparsing import pyparsing_common as ppc
LBRACK, RBRACK, LBRACE, RBRACE, COLON, SEMI = map(Suppress, "[]{}:;")
ident = Word(alphas + "_", alphanums + "_").setName("identifier")
named_types = {}
def generate_header(filename):
print(
"""/* generated code for {filename} */
#include <glib.h>
typedef struct {{
gconstpointer base;
gsize size;
}} VariantChunk;
/* Note: clz is undefinded for 0, so never call this size == 0 */
G_GNUC_CONST static inline guint
variant_chunk_get_offset_size (gsize size)
{{
#if defined(__GNUC__) && (__GNUC__ >= 4) && defined(__OPTIMIZE__)
/* Instead of using a lookup table we use nibbles in a lookup word */
guint32 v = (guint32)0x88884421;
return (v >> (((__builtin_clzl(size) ^ 63) / 8) * 4)) & 0xf;
#else
if (size > G_MAXUINT16)
{{
if (size > G_MAXUINT32)
return 8;
else
return 4;
}}
else
{{
if (size > G_MAXUINT8)
return 2;
else
return 1;
}}
#endif
}}
G_GNUC_PURE static inline gsize
variant_chunk_read_unaligned_le (guchar *bytes, guint size)
{{
union
{{
guchar bytes[GLIB_SIZEOF_SIZE_T];
gsize integer;
}} tmpvalue;
tmpvalue.integer = 0;
/* we unroll the size checks here so that memcpy gets constant args */
if (size >= 4)
{{
if (size == 8)
memcpy (&tmpvalue.bytes, bytes, 8);
else
memcpy (&tmpvalue.bytes, bytes, 4);
}}
else
{{
if (size == 2)
memcpy (&tmpvalue.bytes, bytes, 2);
else
memcpy (&tmpvalue.bytes, bytes, 1);
}}
return GSIZE_FROM_LE (tmpvalue.integer);
}}
""".format(filename=filename))
def generate_footer(filename):
print(
"""
""".format(filename=filename))
def align_down(value, alignment):
return value & ~(alignment - 1)
def align_up(value, alignment):
return align_down(value + alignment - 1, alignment)
def add_named_type(name, type):
assert not name in named_types
type.set_typename(name, True)
named_types[name] = type
def get_named_type(name):
assert name in named_types
return named_types[name]
class TypeDef:
def __init__(self, name, type):
self.name = name
self.type = type
add_named_type(name, type)
def generate(self, generated):
def do_generate (type, generated):
for c in type.get_children():
do_generate (c, generated)
if type.typename != None and type.typename not in generated:
generated[type.typename] = True
type.generate()
do_generate(self.type, generated)
class Type:
def __init__(self):
self.typename = None
def typestring(self):
assert False
def set_typename(self, name, override = False):
if self.typename == None or override:
self.typename = name
self.propagate_typename(name)
def propagate_typename(self, typename):
pass
def is_basic(self):
return False
def is_fixed(self):
return False
def get_fixed_size(self):
assert False # Should not be reached
def alignment(self):
return 1
def get_children(self):
return []
def generate(self):
print("/* TODO: Generate %s -- %s */" % (self.typename, self))
def get_ctype(self):
return self.typename
basic_types = {
"boolean": ("b", True, 1, "gboolean"),
"byte": ("y", True, 1, "guint8"),
"int16": ("n", True, 2, "gint16"),
"uint16": ("q", True, 2, "guint16"),
"int32": ("i", True, 4, "gint32"),
"uint32": ("u", True, 4, "guint32"),
"int64": ("x", True, 8, "gint64"),
"uint64": ("t", True, 8, "guint64"),
"handle": ("h", True, 4, "guint32"),
"double": ("d", True, 8, "double"),
"string": ("s", False, 1, "const char *"),
"objectpath": ("o", False, 1, "const char *"),
"signature": ("g", False, 1, "const char *"),
}
class BasicType(Type):
def __init__(self, kind):
super().__init__()
assert kind in basic_types
self.kind = kind
def __repr__(self):
return "BasicType(%s)" % self.kind
def typestring(self):
return basic_types[self.kind][0]
def set_typename(self, name):
pass # No names for basic types
def is_basic(self):
return True
def is_fixed(self):
return basic_types[self.kind][1]
def get_fixed_size(self):
return basic_types[self.kind][2]
def alignment(self):
return basic_types[self.kind][2]
def get_ctype(self):
return basic_types[self.kind][3]
class ArrayType(Type):
def __init__(self, element_type):
super().__init__()
self.element_type = element_type
if element_type.is_basic():
self.typename = self.element_type.kind + "array"
def __repr__(self):
return "ArrayType<%s>(%s)" % (self.typename, repr(self.element_type))
def typestring(self):
return "a" + self.element_type.typestring()
def propagate_typename(self, name):
self.element_type.set_typename (name + "__element")
def alignment(self):
return self.element_type.alignment()
def get_children(self):
return [self.element_type]
class DictType(Type):
def __init__(self, key_type, element_type):
super().__init__()
self.key_type = key_type
self.element_type = element_type
def __repr__(self):
return "DictType<%s>(%s, %s)" % (self.typename, repr(self.key_type), repr(self.element_type))
def typestring(self):
return "a{%s%s}" % (self.key_type.typestring(), self.element_type.typestring())
def propagate_typename(self, name):
self.element_type.set_typename (name + "__element")
def alignment(self):
return max(self.element_type.alignment(), self.key_type.alignment())
def get_children(self):
return [self.key_type, self.element_type]
class MaybeType(Type):
def __init__(self, element_type):
super().__init__()
self.element_type = element_type
if element_type.is_basic():
self.typename = "maybe" + self.element_type.kind
def __repr__(self):
return "MaybeType<%s>(%s, %s)" % (self.typename, repr(self.element_type))
def typestring(self):
return "m" + self.element_type.typestring()
def propagate_typename(self, name):
self.element_type.set_typename (name + "__element")
def alignment(self):
return self.element_type.alignment()
def get_children(self):
return [self.element_type]
class VariantType(Type):
def __init__(self):
super().__init__()
self.typename = "variant"
def __repr__(self):
return "VariantType()"
def typestring(self):
return "v"
def set_typename(self, name):
pass # No names for variant
def alignment(self):
return 8
class Field:
def __init__(self, name, attributes, type):
self.name = name
self.attributes = attributes
self.type = type
self.last = False
def __repr__(self):
return "Field(%s, %s)" % (self.name, self.type)
def propagate_typename(self, struct_name):
self.type.set_typename (struct_name + "__" + self.name)
def generate(self, struct):
# Getter
print ("static inline {ctype} {structname}_get_{fieldname}({structname} v) {{".format(structname=struct.typename, ctype=self.type.get_ctype(), fieldname=self.name))
if self.offset_index == 0:
offset = "%d" % (self.offset)
else:
print (" guint offset_size = variant_chunk_get_offset_size (v.size);");
print (" gsize last_end = variant_chunk_read_unaligned_le ((guchar*)(v.base) + v.size - offset_size * %d, offset_size);" % self.offset_index);
if self.offset_alignment == 1:
offset = "last_end + %d" % (self.offset)
else:
offset = "((last_end + %d) & (~(gsize)%d)) + %d" % (self.offset_alignment - 1, self.offset_alignment - 1, self.offset)
if self.type.is_basic():
if self.type.is_fixed():
print (" return G_STRUCT_MEMBER(%s, v.base, %s);" % (self.type.get_ctype(), offset))
else: # string
print (" return &G_STRUCT_MEMBER(char, v.base, %s);" % (offset))
else:
if self.type.is_fixed():
print (" %s val = { &G_STRUCT_MEMBER(void, v.base, %s), %d }" % (self.type.typename, offset, self.type.get_fixed_size()))
print (" return val;")
else:
print (" gsize start = %s;" % offset);
if self.last:
print (" gsize end = v.size - offset_size * %d;" % (struct.framing_offset_size))
else:
print (" gsize end = variant_chunk_read_unaligned_le ((guchar*)(v.base) + v.size - offset_size * %d, offset_size);" % (self.offset_index + 1));
print (" %s val = { G_STRUCT_MEMBER_P(v.base, start), end - start };" % (self.type.typename))
print (" return val;")
print("}")
class StructType(Type):
def __init__(self, fields):
super().__init__()
self.fields = list(fields)
if len(self.fields) > 0:
self.fields[len(self.fields) - 1].last = True
framing_offset_size = 0
pos = 0
index = 0
alignment = -1;
for f in fields:
pos = align_up(pos, f.type.alignment())
f.offset = pos
f.offset_index = index
if alignment == -1:
alignment = f.type.alignment()
f.offset_alignment = alignment
if f.type.is_fixed():
pos = pos + f.type.get_fixed_size()
else:
if not f.last:
framing_offset_size = framing_offset_size + 1
pos = 0
index = index + 1
alignment = -1
self.framing_offset_size = framing_offset_size
self._fixed = (index == 0)
if self._fixed:
if pos == 0:
self._fixed_size = 1; # Special case unit struct
else:
# Round up to aligement
self._fixed_size = align_up(pos, self.alignment())
def __repr__(self):
return "StructType<%s>(%s)" % (self.typename, ",".join(map(repr, self.fields)))
def typestring(self):
res = ['(']
for f in self.fields:
res.append(f.type.typestring())
res.append(')')
return "".join(res)
def get_children(self):
children = []
for f in self.fields:
children.append(f.type)
return children
def propagate_typename(self, name):
for f in self.fields:
f.propagate_typename(name)
def alignment(self):
alignment = 1;
for f in self.fields:
alignment = max(alignment, f.type.alignment())
return alignment
def is_fixed(self):
return self._fixed;
def get_fixed_size(self):
return self._fixed_size
def generate(self):
print (
'''
typedef VariantChunk {typename};
#define {typename}_typestring "{typestring}"
static inline {typename} {typename}_from_variant(GVariant *v) {{
{typename} val = {{ g_variant_get_data (v), g_variant_get_size (v) }};
return val;
}}'''.format(typename=self.typename, typestring=self.typestring()))
for f in self.fields:
f.generate(self)
typeSpec = Forward()
basicType = oneOf(basic_types.keys()).setParseAction(lambda toks: BasicType(toks[0]))
variantType = Keyword("variant").setParseAction(lambda toks: VariantType())
arrayType = (LBRACK + RBRACK + typeSpec).setParseAction(lambda toks: ArrayType(toks[0]))
dictType = (LBRACK + basicType + RBRACK + typeSpec).setParseAction(lambda toks: DictType(toks[0], toks[1]))
maybeType = (Suppress("?") + typeSpec).setParseAction(lambda toks: MaybeType(toks[0]))
fieldAttribute = oneOf("bigendian littleendian nativeendian")
field = (ident + COLON + Group(ZeroOrMore(fieldAttribute)) + typeSpec + SEMI).setParseAction(lambda toks: Field(toks[0], toks[1], toks[2]))
structType = (LBRACE + ZeroOrMore(field) + RBRACE).setParseAction(lambda toks: StructType(toks))
namedType = ident.copy().setParseAction(lambda toks: get_named_type(str(toks[0])))
typeSpec <<= basicType ^ arrayType ^ maybeType ^ variantType ^ dictType ^ structType ^ namedType
typeDef = (Suppress(Keyword("type")) + ident + typeSpec + SEMI).setParseAction(lambda toks: TypeDef(toks[0], toks[1]))
typeDefs = ZeroOrMore(typeDef).ignore(cppStyleComment)
def generate(typedefs, filename):
generate_header(filename)
generated = {}
for td in typedefs:
td.generate(generated)
generate_footer(filename)
if __name__ == "__main__":
file = sys.argv[1]
with open(file, "r") as f:
testdata = f.read()
try:
typedefs = typeDefs.parseString(testdata, parseAll=True)
generate(typedefs, os.path.basename(file))
except ParseException as pe:
print("Parse error:", pe)