In Files
- dl/lib/dl/struct.rb
Parent
(DL.fiddle? ? Fiddle::Pointer : CPtr)
Methods
Included Modules
Class/Module Index
![[+]](../images/find.png "show/hide quicksearch")
- DL
- DL::BasicTypes
- DL::CFunc
- DL::CParser
- DL::CPtr
- DL::CStruct
- DL::CStructBuilder
- DL::CStructEntity
- DL::CUnion
- DL::CUnionEntity
- DL::CarriedFunction
- DL::CompositeHandler
- DL::DLError
- DL::DLTypeError
- DL::Function
- DL::Handle
- DL::Importer
- DL::Packer
- DL::Stack
- DL::TempFunction
- DL::ValueUtil
- DL::Win32Types
- Object
DL::CStructEntity
A C struct wrapper
Public Class Methods
Allocates a C struct the types provided. The C function
func is called when the instance is garbage collected.
# File dl/lib/dl/struct.rb, line 85
def CStructEntity.malloc(types, func = nil)
addr = DL.malloc(CStructEntity.size(types))
CStructEntity.new(addr, types, func)
end
Wraps the C pointer addr as a C struct with the given
types. The C function func is called when the
instance is garbage collected.
See also DL::CPtr.new
# File dl/lib/dl/struct.rb, line 115
def initialize(addr, types, func = nil)
set_ctypes(types)
super(addr, @size, func)
end
Given types, returns the offset for the packed sizes of those
types
DL::CStructEntity.size([DL::TYPE_DOUBLE, DL::TYPE_INT, DL::TYPE_CHAR, DL::TYPE_VOIDP]) => 24
# File dl/lib/dl/struct.rb, line 95
def CStructEntity.size(types)
offset = 0
max_align = types.map { |type, count = 1|
last_offset = offset
align = PackInfo::ALIGN_MAP[type]
offset = PackInfo.align(last_offset, align) +
(PackInfo::SIZE_MAP[type] * count)
align
}.max
PackInfo.align(offset, max_align)
end
Public Instance Methods
Fetch struct member name
# File dl/lib/dl/struct.rb, line 148
def [](name)
idx = @members.index(name)
if( idx.nil? )
raise(ArgumentError, "no such member: #{name}")
end
ty = @ctypes[idx]
if( ty.is_a?(Array) )
r = super(@offset[idx], SIZE_MAP[ty[0]] * ty[1])
else
r = super(@offset[idx], SIZE_MAP[ty.abs])
end
packer = Packer.new([ty])
val = packer.unpack([r])
case ty
when Array
case ty[0]
when TYPE_VOIDP
val = val.collect{|v| CPtr.new(v)}
end
when TYPE_VOIDP
val = CPtr.new(val[0])
else
val = val[0]
end
if( ty.is_a?(Integer) && (ty < 0) )
return unsigned_value(val, ty)
elsif( ty.is_a?(Array) && (ty[0] < 0) )
return val.collect{|v| unsigned_value(v,ty[0])}
else
return val
end
end
Set struct member name, to value val
# File dl/lib/dl/struct.rb, line 182
def []=(name, val)
idx = @members.index(name)
if( idx.nil? )
raise(ArgumentError, "no such member: #{name}")
end
ty = @ctypes[idx]
packer = Packer.new([ty])
val = wrap_arg(val, ty, [])
buff = packer.pack([val].flatten())
super(@offset[idx], buff.size, buff)
if( ty.is_a?(Integer) && (ty < 0) )
return unsigned_value(val, ty)
elsif( ty.is_a?(Array) && (ty[0] < 0) )
return val.collect{|v| unsigned_value(v,ty[0])}
else
return val
end
end
Set the names of the members in this C struct
# File dl/lib/dl/struct.rb, line 121
def assign_names(members)
@members = members
end
Given types, calculate the offsets and sizes for the types in
the struct.
# File dl/lib/dl/struct.rb, line 127
def set_ctypes(types)
@ctypes = types
@offset = []
offset = 0
max_align = types.map { |type, count = 1|
orig_offset = offset
align = ALIGN_MAP[type]
offset = PackInfo.align(orig_offset, align)
@offset << offset
offset += (SIZE_MAP[type] * count)
align
}.max
@size = PackInfo.align(offset, max_align)
end
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