generator: _c_accessor_get_length: remove buggy special case
[free-sw/xcb/libxcb] / src / c_client.py
index 0a1f877..88321f4 100644 (file)
@@ -58,6 +58,107 @@ def _hc(fmt, *args):
     _h(fmt, *args)
     _c(fmt, *args)
 
+def _c_wr_stringlist(indent, strlist):
+    '''
+    Writes the given list of strings to the source file.
+    Each line is prepended by the indent string
+    '''
+    for str in strlist:
+        _c("%s%s", indent, str)
+
+
+class PreCode(object):
+    '''
+    For pre-code generated by expression generation
+    (for example, the for-loop of a sumof)
+    This has to account for recursiveness of the expression
+    generation, i.e., there may be pre-code for pre-code.
+    Therefore this is implemented as a stack of lists of lines.
+
+    If redirection is switched on, then all output is collected in
+    self.redirect_code and self.redirect_tempvars instead of
+    being sent to the output via _h und _c.
+    '''
+    def __init__(self):
+        self.nesting_level = 0
+        self.tempvars = []
+        self.codelines = []
+        self.redirect_code = None
+        self.redirect_tempvars = None
+        self.indent_str = '    '
+        self.indent_stack = []
+        self.tempvar_num = 0
+
+
+    # start and end of pre-code blocks
+    def start(self):
+        self.nesting_level += 1
+
+    def end(self):
+        self.nesting_level -= 1
+        if self.nesting_level == 0:
+            # lowest pre-code level is finished -> output to source
+            if self.redirect_tempvars is None:
+                _c_wr_stringlist('', self.tempvars)
+                self.tempvars = []
+            else:
+                self.redirect_tempvars.extend(self.tempvars)
+                self.tempvars = []
+            if self.redirect_code == None:
+                _c_wr_stringlist('', self.codelines)
+                self.codelines = []
+            else:
+                self.redirect_code.extend(self.codelines)
+                self.codelines = []
+
+
+    def output_tempvars(self):
+        if self.redirect_code == None:
+            _c_wr_stringlist('', self.tempvars)
+            self.tempvars = []
+
+    # output to precode
+    def code(self, fmt, *args):
+        self.codelines.append(self.indent_str + fmt % args)
+
+    def tempvar(self, fmt, *args):
+        self.tempvars.append('    ' + (fmt % args))
+
+    # get a unique name for a temporary variable
+    def get_tempvarname(self):
+        self.tempvar_num += 1
+        return "xcb_pre_tmp_%d" % self.tempvar_num
+
+    # indentation
+
+    def push_indent(self, indentstr):
+        self.indent_stack.append(self.indent_str)
+        self.indent_str = indentstr
+
+    def push_addindent(self, indent_add_str):
+        self.push_indent(self.indent_str + indent_add_str)
+
+    def indent(self):
+        self.push_addindent('    ')
+
+    def pop_indent(self):
+        self.indent_str = self.indent_stack.pop()
+
+    # redirection to lists
+    def redirect_start(self, redirect_code, redirect_tempvars=None):
+        self.redirect_code = redirect_code
+        self.redirect_tempvars = redirect_tempvars
+        if redirect_tempvars is not None:
+            self.tempvar_num = 0
+
+    def redirect_end(self):
+        self.redirect_code = None
+        self.redirect_tempvars = None
+
+# global PreCode handler
+_c_pre = PreCode()
+
+
 # XXX See if this level thing is really necessary.
 def _h_setlevel(idx):
     '''
@@ -336,12 +437,6 @@ def _c_type_setup(self, name, postfix):
         first_field_after_varsized = None
 
         for field in self.fields:
-            _c_type_setup(field.type, field.field_type, ())
-            if field.type.is_list:
-                _c_type_setup(field.type.member, field.field_type, ())
-                if (field.type.nmemb is None):
-                    self.c_need_sizeof = True
-
             field.c_field_type = _t(field.field_type)
             field.c_field_const_type = ('' if field.type.nmemb == 1 else 'const ') + field.c_field_type
             field.c_field_name = _cpp(field.field_name)
@@ -391,6 +486,15 @@ def _c_type_setup(self, name, postfix):
                 if field.type.fixed_size():
                     field.prev_varsized_field = None
 
+            # recurse into this field this has to be done here, i.e.,
+            # after the field has been set up. Otherwise the function
+            # _c_helper_fieldaccess_expr will produce garbage or crash
+            _c_type_setup(field.type, field.field_type, ())
+            if field.type.is_list:
+                _c_type_setup(field.type.member, field.field_type, ())
+                if (field.type.nmemb is None):
+                    self.c_need_sizeof = True
+
     if self.c_need_serialize:
         # when _unserialize() is wanted, create _sizeof() as well for consistency reasons
         self.c_need_sizeof = True
@@ -427,23 +531,64 @@ def _c_type_setup(self, name, postfix):
                     _c_serialize('sizeof', self)
 # _c_type_setup()
 
-def _c_helper_absolute_name(prefix, field=None):
+# Functions for querying field properties
+def _c_field_needs_list_accessor(field):
+    return field.type.is_list and not field.type.fixed_size()
+
+def _c_field_needs_field_accessor(field):
+    if field.type.is_list:
+        return False
+    else:
+        return (field.prev_varsized_field is not None or
+                not field.type.fixed_size())
+
+def _c_field_needs_accessor(field):
+    return (_c_field_needs_list_accessor(field) or
+            _c_field_needs_field_accessor(field))
+
+def _c_field_is_member_of_case_or_bitcase(field):
+    return field.parent and field.parent.is_case_or_bitcase
+
+def _c_helper_fieldaccess_expr(prefix, field=None):
     """
     turn prefix, which is a list of tuples (name, separator, Type obj) into a string
-    representing a valid name in C (based on the context)
-    if field is not None, append the field name as well
+    representing a valid field-access-expression in C (based on the context)
+    if field is not None, append access to the field as well.
+
+    "separator" is one of the C-operators "." or "->".
+
+    A field access expression can consist of the following components:
+    * struct/union member access from a value with the "."-operator
+    * struct/union member access from a pointer with "->"-operator
+    * function-call of an accessor function:
+      This is used when a xcb-field is not contained in a struct.
+      This can, e.g., happen for fields after var-sized fields, etc.
     """
     prefix_str = ''
+    last_sep =''
     for name, sep, obj in prefix:
-        prefix_str += name
-        if '' == sep:
-            sep = '->'
-            if ((obj.is_case_or_bitcase and obj.has_name) or     # named bitcase
-                (obj.is_switch and len(obj.parents)>1)):
-                sep = '.'
-        prefix_str += sep
-    if field is not None:
-        prefix_str += _cpp(field.field_name)
+        prefix_str += last_sep + name
+        last_sep = sep
+
+    if field is None:
+        # add separator for access to a yet unknown field
+        prefix_str += last_sep
+    else:
+        if _c_field_needs_accessor(field):
+            if _c_field_is_member_of_case_or_bitcase(field):
+                # case members are available in the deserialized struct,
+                # so there is no need to use the accessor function
+                # (also, their accessor function needs a different arglist
+                # so this would require special treatment here)
+                # Therefore: Access as struct member
+                prefix_str += last_sep + _cpp(field.field_name)
+            else:
+                # Access with the accessor function
+                prefix_str = field.c_accessor_name + "(" + prefix_str + ")"
+        else:
+            # Access as struct member
+            prefix_str += last_sep + _cpp(field.field_name)
+
     return prefix_str
 # _c_absolute_name
 
@@ -465,7 +610,7 @@ def _c_helper_field_mapping(complex_type, prefix, flat=False):
                 all_fields.update(_c_helper_field_mapping(b.type, bitcase_prefix, flat))
     else:
         for f in complex_type.fields:
-            fname = _c_helper_absolute_name(prefix, f)
+            fname = _c_helper_fieldaccess_expr(prefix, f)
             if f.field_name in all_fields:
                 raise Exception("field name %s has been registered before" % f.field_name)
 
@@ -750,7 +895,7 @@ def _c_serialize_helper_switch_field(context, self, field, c_switch_variable, pr
     # switch is handled by this function as a special case
     param_fields, wire_fields, params = get_serialize_params(context, self)
     field_mapping = _c_helper_field_mapping(self, prefix)
-    prefix_str = _c_helper_absolute_name(prefix)
+    prefix_str = _c_helper_fieldaccess_expr(prefix)
 
     # find the parameters that need to be passed to _serialize()/_unpack():
     # all switch expr fields must be given as parameters
@@ -794,7 +939,7 @@ def _c_serialize_helper_list_field(context, self, field,
     helper function to cope with lists of variable length
     """
     expr = field.type.expr
-    prefix_str = _c_helper_absolute_name(prefix)
+    prefix_str = _c_helper_fieldaccess_expr(prefix)
     param_fields, wire_fields, params = get_serialize_params('sizeof', self)
     param_names = [p[2] for p in params]
 
@@ -865,7 +1010,7 @@ def _c_serialize_helper_fields_fixed_size(context, self, field,
         typename = reduce(lambda x,y: "%s.%s" % (x, y), scoped_name)
         code_lines.append('%s    /* %s.%s */' % (space, typename, field.c_field_name))
 
-    abs_field_name = _c_helper_absolute_name(prefix, field)
+    abs_field_name = _c_helper_fieldaccess_expr(prefix, field)
     # default for simple cases: call sizeof()
     length = "sizeof(%s)" % field.c_field_type
 
@@ -927,7 +1072,7 @@ def _c_serialize_helper_fields_fixed_size(context, self, field,
 def _c_serialize_helper_fields_variable_size(context, self, field,
                                              code_lines, temp_vars,
                                              space, prefix):
-    prefix_str = _c_helper_absolute_name(prefix)
+    prefix_str = _c_helper_fieldaccess_expr(prefix)
 
     if context in ('unserialize', 'unpack', 'sizeof'):
         value = ''
@@ -984,6 +1129,8 @@ def _c_serialize_helper_fields(context, self,
     need_padding = False
     prev_field_was_variable = False
 
+    _c_pre.push_indent(space + '    ')
+
     for field in self.fields:
         if not field.visible:
             if not ((field.wire and not field.auto) or 'unserialize' == context):
@@ -1072,6 +1219,8 @@ def _c_serialize_helper_fields(context, self,
         if self.c_var_followed_by_fixed_fields:
             need_padding = False
 
+    _c_pre.pop_indent()
+
     return count
 # _c_serialize_helper_fields()
 
@@ -1170,6 +1319,8 @@ def _c_serialize(context, self):
     temp_vars = []
     prefix = []
 
+    _c_pre.redirect_start(code_lines, temp_vars)
+
     if 'serialize' == context:
         if not self.is_switch and not self.c_var_followed_by_fixed_fields:
             _c('    %s *xcb_out = *_buffer;', self.c_type)
@@ -1215,11 +1366,13 @@ def _c_serialize(context, self):
             _c('    %s _aux;', self.c_type)
             _c('    return %s(%s, &_aux);', self.c_unpack_name, reduce(lambda x,y: "%s, %s" % (x, y), param_names))
             _c('}')
+            _c_pre.redirect_end()
             return
         elif self.c_var_followed_by_fixed_fields:
             # special case: call _unserialize()
             _c('    return %s(%s, NULL);', self.c_unserialize_name, reduce(lambda x,y: "%s, %s" % (x, y), param_names))
             _c('}')
+            _c_pre.redirect_end()
             return
         else:
             _c('    char *xcb_tmp = (char *)_buffer;')
@@ -1255,6 +1408,8 @@ def _c_serialize(context, self):
             _c('    unsigned int xcb_pad = 0;')
             _c('    unsigned int xcb_align_to = 0;')
 
+    _c_pre.redirect_end()
+
     _c('')
     for t in temp_vars:
         _c(t)
@@ -1435,12 +1590,7 @@ def _c_accessor_get_length(expr, field_mapping=None):
         if field_mapping is not None:
             lenfield_name = field_mapping[lenfield_name][0]
 
-    if expr.lenfield is not None and expr.lenfield.prev_varsized_field is not None:
-        # special case: variable and fixed size fields are intermixed
-        # if the lenfield is among the fixed size fields, there is no need
-        # to call a special accessor function like <expr.lenfield.c_accessor_name + '(' + prefix + ')'>
-        return field_mapping(expr.lenfield_name)
-    elif expr.lenfield_name is not None:
+    if expr.lenfield_name is not None:
         return lenfield_name
     else:
         return str(expr.nmemb)
@@ -1477,9 +1627,54 @@ def _c_accessor_get_expr(expr, field_mapping):
             raise Exception("list field '%s' referenced by sumof not found" % expr.lenfield_name)
         list_name = field_mapping[field.c_field_name][0]
         c_length_func = "%s(%s)" % (field.c_length_name, list_name)
-        # note: xcb_sumof() has only been defined for integers
         c_length_func = _c_accessor_get_expr(field.type.expr, field_mapping)
-        return 'xcb_sumof(%s, %s)' % (list_name, c_length_func)
+        # create explicit code for computing the sum.
+        # This works for all C-types which can be added to int64_t with +=
+        _c_pre.start()
+        lengthvar = _c_pre.get_tempvarname()
+        loopvar = _c_pre.get_tempvarname()
+        sumvar = _c_pre.get_tempvarname()
+        listvar = _c_pre.get_tempvarname()
+        _c_pre.tempvar("int %s; /* sumof length */", lengthvar)
+        _c_pre.tempvar("int %s; /* sumof loop counter */", loopvar)
+        _c_pre.tempvar("int64_t %s; /* sumof sum */", sumvar)
+        _c_pre.tempvar("const %s* %s; /* sumof list ptr */", field.c_field_type, listvar)
+        _c_pre.code("/* sumof start */")
+        _c_pre.code("%s = %s;", lengthvar, c_length_func)
+        _c_pre.code("%s = 0;", sumvar)
+        _c_pre.code("%s = %s;", listvar, list_name)
+        _c_pre.code("for (%s = 0; %s < %s; %s++) {", loopvar, loopvar, lengthvar, loopvar)
+        _c_pre.indent()
+
+        if expr.rhs is None:
+            _c_pre.code("%s += *%s;", sumvar, listvar)
+        else:
+            # sumof has a nested expression which has to be evaluated in
+            # the context of this list element
+
+            # field mapping for the subexpression needs to include
+            # the fields of the list-member type
+            scoped_field_mapping = field_mapping.copy()
+            scoped_field_mapping.update(
+                _c_helper_field_mapping(
+                    field.type.member,
+                    [(listvar, '->', field.type.member)]))
+
+            # cause pre-code of the subexpression be added right here
+            _c_pre.end()
+            # compute the subexpression
+            rhs_expr_str = _c_accessor_get_expr(expr.rhs, scoped_field_mapping)
+            # resume with our code
+            _c_pre.start()
+            # output the summation expression
+            _c_pre.code("%s += %s;", sumvar, rhs_expr_str)
+
+        _c_pre.code("%s++;", listvar)
+        _c_pre.pop_indent()
+        _c_pre.code("}")
+        _c_pre.code("/* sumof end. Result is in %s */", sumvar)
+        _c_pre.end()
+        return sumvar
     elif expr.op != None:
         return ('(' + _c_accessor_get_expr(expr.lhs, field_mapping) +
                 ' ' + expr.op + ' ' +
@@ -1644,12 +1839,11 @@ def _c_accessors_list(self, field):
         spacing = ' '*(len(field.c_length_name)+2)
         _h('%sconst %s *S /**< */);', spacing, S_obj.c_type)
         _c('%sconst %s *S  /**< */)', spacing, S_obj.c_type)
-        length = _c_accessor_get_expr(field.type.expr, fields)
     else:
         _h('%s (const %s *R  /**< */);', field.c_length_name, c_type)
         _c('%s (const %s *R  /**< */)', field.c_length_name, c_type)
-        length = _c_accessor_get_expr(field.type.expr, fields)
     _c('{')
+    length = _c_accessor_get_expr(field.type.expr, fields)
     _c('    return %s;', length)
     _c('}')
 
@@ -1699,10 +1893,15 @@ def _c_accessors_list(self, field):
         _c('{')
         _c('    %s i;', field.c_iterator_type)
 
+        _c_pre.start()
+        length_expr_str = _c_accessor_get_expr(field.type.expr, fields)
+
         if switch_obj is not None:
+            _c_pre.end()
             _c('    i.data = %s;', fields[field.c_field_name][0])
-            _c('    i.rem = %s;', _c_accessor_get_expr(field.type.expr, fields))
+            _c('    i.rem = %s;', length_expr_str)
         elif field.prev_varsized_field == None:
+            _c_pre.end()
             _c('    i.data = (%s *) (R + 1);', field.c_field_type)
         else:
             (prev_varsized_field, align_pad) = get_align_pad(field)
@@ -1713,11 +1912,12 @@ def _c_accessors_list(self, field):
 
             _c('    xcb_generic_iterator_t prev = %s;',
                 _c_iterator_get_end(prev_varsized_field, 'R'))
+            _c_pre.end()
             _c('    i.data = (%s *) ((char *) prev.data + %s);',
                 field.c_field_type, align_pad)
 
         if switch_obj is None:
-            _c('    i.rem = %s;', _c_accessor_get_expr(field.type.expr, fields))
+            _c('    i.rem = %s;', length_expr_str)
         _c('    i.index = (char *) i.data - (char *) %s;', 'R' if switch_obj is None else 'S' )
         _c('    return i;')
         _c('}')
@@ -1734,9 +1934,9 @@ def _c_accessors(self, name, base):
     if True:
         for field in self.fields:
             if not field.type.is_pad:
-                if field.type.is_list and not field.type.fixed_size():
+                if _c_field_needs_list_accessor(field):
                     _c_accessors_list(self, field)
-                elif field.prev_varsized_field is not None or not field.type.fixed_size():
+                elif _c_field_needs_field_accessor(field):
                     _c_accessors_field(self, field)
 
 def c_simple(self, name):
@@ -1804,7 +2004,7 @@ def _c_complex(self, force_packed = False):
         for b in self.bitcases:
             space = ''
             if b.type.has_name:
-                _h('    struct _%s {', b.c_field_name)
+                _h('    struct {')
                 space = '    '
             for field in b.type.fields:
                 _c_complex_field(self, field, space)
@@ -2870,7 +3070,18 @@ def c_event(self, name):
                 force_packed = any(f.type.size == 8 and f.type.is_simple for f in self.fields[(idx+1):])
                 break
 
-    _c_type_setup(self, name, ('event',))
+    if self.name == name:
+        _c_type_setup(self, name, ('event',))
+        # generate accessors
+        # (needed for fields after var-sized fields, for lists with var-sized elements,
+        # switches, ...)
+        _c_accessors(self, name, name)
+    else:
+        # no type-setup needed for eventcopies
+        # (the type-setup of an eventcopy would overwrite members of the original
+        # event, and it would create sizeof-etc funtions which
+        # called undefined accessor functions)
+        pass
 
     # Opcode define
     _c_opcode(name, self.opcodes[name])
@@ -2883,6 +3094,22 @@ def c_event(self, name):
         _h('')
         _h('typedef %s %s;', _t(self.name + ('event',)), _t(name + ('event',)))
 
+        # Create sizeof-function for eventcopies for compatibility reasons
+        if self.c_need_sizeof:
+            _h_setlevel(1)
+            _c_setlevel(1)
+            _h('')
+            _h('int')
+            _h('%s (const void  *_buffer  /**< */);', _n(name + ('sizeof',)))
+            _c('')
+            _c('int')
+            _c('%s (const void  *_buffer  /**< */)', _n(name + ('sizeof',)))
+            _c('{');
+            _c('    return %s(_buffer);', _n(self.name + ('sizeof',)))
+            _c('}');
+            _h_setlevel(0)
+            _c_setlevel(0)
+
     _man_event(self, name)
 
 def c_error(self, name):