[ Sorry for the hindrance ] <div class="gmail_quote">On Tue, Jul 5, 2011 at 12:18 AM, Jamey Sharp <<a href="mailto:jamey@minilop.net">jamey@minilop.net</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"> <div class="im">On Mon, Jul 04, 2011 at 03:42:24AM +0530, vikash agrawal wrote: > Also it has been long I am trying to patch a bug, I had several discussion > with pharris ( I apologise for pestering you so much ) over the same. I am > still studying c_client.py and a quick glance of it reveals > '_c_serialize_helper_insert_ function', with context being sizeof, is > responsible for xcb_str_sizeof in xproto.c. So I believe this might need > some hacks. > Also, if I am not wrong there is a problem with xcb_str_next with respect > master and 1.7, but for this I have a very n00b and basic idea like if > self.c_next_name == 'xcb_str_next': # and then necessary conditions of > _c('whatever'); might solve the purpose. If this feels a way then can we > specifically do the same for other buggy issues. </div>I'm sorry to say, the problem is not specific to xcb_str_next or to strings at all. The good news is that it should be solvable in a general way, without hacks for specific types. I wrote some about this here: <a href="http://lists.freedesktop.org/archives/xcb/2011-March/006837.html" target="_blank">http://lists.freedesktop.org/archives/xcb/2011-March/006837.html</a> Here is a sketch of an algorithm that I believe is correct for statically computing alignment padding for all X types. I'll use the terms from xcbgen/xtypes.py. First, compute the minimum alignment requirement for every type: - For every SimpleType and ExprType, including the standard types like CARD8, the alignment required equals the size of the type, but no more than 4 bytes. So CARD8 needs 1 byte, INT16 needs 2 bytes, FLOAT needs 4 bytes, and DOUBLE also needs 4 bytes. - For ListTypes, the alignment is the same as the member type's alignment. - Request, Reply, Event, and Error types always have 4-byte alignment. - For StructType and UnionType, the alignment is the maximum alignment needed by any field in the struct or union. So STR, which is a struct containing a CARD8 and a list of CARD8, only needs 1-byte alignment; but a struct containing an INT16 and a DOUBLE needs 4-byte alignment. I haven't thought about the rules for Switch or Bitcase yet. I think implementing the above in proto/xcbgen would be a good target for something to finish by the time of the mid-term review. The rest of the algorithm is below. </blockquote><div> Hello Everyone, Thank You Jamey for the reply, I am facing few problems, <ul><li>I am unable to compile xtypes.py with python interpretor. I reciev an error -> Traceback (most recent call last): File "workspace/xcb/proto/xcbgen/xtypes.py", line 80, in <module> class SimpleType(Type): File "workspace/xcb/proto/xcbgen/xtypes.py", line 106, in SimpleType out = __main__.output['simple'] AttributeError: 'module' object has no attribute 'output' and as a result for every change that I try to bring I need to start from make clean all over again for both ptroto</li> <li>module.resolve keep troubling me whenever I try to introduce something in the xtypes so how can I resolve those</li></ul>So far what I have understood/interpreted from your reply I have tried to do something, ( and its compiling :-) ) and here it is, please review it [ I have tried to have follow the coding style and tried not not to make any typo error, still if any prob occur please notify ] [vikash@localhost proto]$ git diff diff --git a/xcbgen/xtypes.py b/xcbgen/xtypes.py index 14c318a..98c6811 100644 --- a/xcbgen/xtypes.py +++ b/xcbgen/xtypes.py @@ -34,6 +34,7 @@ class Type(object): self.is_pad = False self.is_switch = False self.is_bitcase = False + self.is_align = False def resolve(self, module): ''' @@ -89,13 +90,19 @@ class SimpleType(Type): self.is_simple = True self.size = size self.nmemb = 1 + + # align should be either equal to self.size or 4 + self.align = min(self.size, 4) + self.is_align = True if self.align else False +# print self.is_align + def resolve(self, module): self.resolved = True def fixed_size(self): return True - + out = __main__.output['simple'] @@ -169,6 +176,15 @@ class ListType(Type): self.size = member.size if member.fixed_size() else None self.nmemb = self.expr.nmemb if self.expr.fixed_size() else None + + # Please look over here + # align should be between size and 4 + # What should I take instead of None ? + self.align = min (member.size, 4) if member.fixed_size() else None + self.is_align = True if self.align else False +# print self.is_align +# Also many a time I am recieving self.align = 0 + def make_member_of(self, module, complex_type, field_type, field_name, v if not self.fixed_size(): @@ -231,6 +247,13 @@ class ExprType(Type): self.size = member.size self.nmemb = 1 + + # align should be either equal to size or 4 + self.align = min(self.size, 4) + self.is_align = True if self.align else False + print self.align +# print self.is_align + def resolve(self, module): if self.resolved: @@ -273,6 +296,8 @@ class ComplexType(Type): self.nmemb = 1 self.size = 0 self.lenfield_parent = [self] + self.align = [] + def resolve(self, module): if self.resolved: @@ -329,7 +354,8 @@ class ComplexType(Type): self.calc_size() # Figure out how big we are self.resolved = True - + self.align_size() + def calc_size(self): self.size = 0 for m in self.fields: @@ -337,7 +363,6 @@ class ComplexType(Type): continue if m.type.fixed_size(): self.size = self.size + (m.type.size * m.type.nmemb) - else: self.size = None break @@ -346,6 +371,29 @@ class ComplexType(Type): if not m.type.fixed_size(): return False return True + + def align_size(self): + ''' + I think this func should work for both StructTypes and UnionTypes + ''' + self.size = 0 + arr=[] + for m in self.fields: + if not m.wire: + continue + if m.type.fixed_size(): + self.size = self.size + (m.type.size * m.type.nmemb) +# print 'calc_size',self.size + arr.append(self.size) +# print 'arr', arr +# print 'max of arr', max(arr) + self.align=min(max(arr), 4) + print 'align', self.align + self.is_align = True +# return self.size + + + class SwitchType(ComplexType): ''' @@ -455,6 +503,7 @@ class Struct(ComplexType): ''' Derived class representing a struct data type. ''' + out = __main__.output['struct'] @@ -518,6 +567,12 @@ class Reply(ComplexType): def __init__(self, name, elt): ComplexType.__init__(self, name, elt) self.is_reply = True + + # align should be equal to 4 + self.align = 4 + self.is_align = True if self.is_align else False +# print self.is_align + def resolve(self, module): if self.resolved: @@ -542,6 +597,12 @@ class Request(ComplexType): ComplexType.__init__(self, name, elt) self.reply = None self.opcode = elt.get('opcode') + + # align should be equal to 4 + self.align = 4 + self.is_align = True if self.align else False +# print self.is_align + for child in list(elt): if child.tag == 'reply': @@ -578,6 +639,11 @@ class Event(ComplexType): def __init__(self, name, elt): ComplexType.__init__(self, name, elt) self.opcodes = {} + + # align should be equal to 4 + self.align = 4 + self.is_align = True if self.align else False +# print self.is_align tmp = elt.get('no-sequence-number') self.has_seq = (tmp == None or tmp.lower() == 'false' or tmp == '0') @@ -611,7 +677,12 @@ class Error(ComplexType): def __init__(self, name, elt): ComplexType.__init__(self, name, elt) self.opcodes = {} - + + # align should be equal to 4 + self.align = 4 + self.is_align = True if self.align else False +# print self.is_align + def add_opcode(self, opcode, name, main): self.opcodes[name] = opcode if main: Love Vikash and waiting for review :) </div></div>