DL::Importer includes the means to dynamically load libraries and build modules around them including calling extern functions within the C library that has been loaded.
require 'dl' require 'dl/import' module LibSum extend DL::Importer dlload './libsum.so' extern 'double sum(double*, int)' extern 'double split(double)' end
# File dl/lib/dl/import.rb, line 192
def [](name)
@func_map[name]
end
# File dl/lib/dl/import.rb, line 152
def bind(signature, *opts, &blk)
name, ctype, argtype = parse_signature(signature, @type_alias)
h = parse_bind_options(opts)
case h[:callback_type]
when :bind, nil
f = bind_function(name, ctype, argtype, h[:call_type], &blk)
when :temp, :temporal
f = create_temp_function(name, ctype, argtype, h[:call_type])
when :carried
f = create_carried_function(name, ctype, argtype, h[:call_type], h[:carrier])
else
raise(RuntimeError, "unknown callback type: #{h[:callback_type]}")
end
@func_map[name] = f
#define_method(name){|*args,&block| f.call(*args,&block)}
begin
/^(.+?):(\d+)/ =~ caller.first
file, line = $1, $2.to_i
rescue
file, line = __FILE__, __LINE__+3
end
module_eval(" def #{name}(*args,&block)
@func_map['#{name}'].call(*args,&block)
end
", file, line)
module_function(name)
f
end
# File dl/lib/dl/import.rb, line 232
def bind_function(name, ctype, argtype, call_type = nil, &block)
if DL.fiddle?
klass = Function.instance_eval { class_fiddle_closure_cfunc }
abi = Function.instance_eval { call_type_to_abi(call_type) }
closure = Class.new(klass) {
define_method(:call, block)
}.new(ctype, argtype, abi, name)
Function.new(closure, argtype, abi)
else
f = Function.new(CFunc.new(0, ctype, name, call_type || :cdecl), argtype)
f.bind(&block)
f
end
end
# File dl/lib/dl/import.rb, line 252
def create_carried_function(name, ctype, argtype, call_type = nil, n = 0)
CarriedFunction.new(CFunc.new(0, ctype, name, call_type || :cdecl), argtype, n)
end
# File dl/lib/dl/import.rb, line 248
def create_temp_function(name, ctype, argtype, call_type = nil)
TempFunction.new(CFunc.new(0, ctype, name, call_type || :cdecl), argtype)
end
# File dl/lib/dl/import.rb, line 196
def create_value(ty, val=nil)
s = struct([ty + " value"])
ptr = s.malloc()
if( val )
ptr.value = val
end
return ptr
end
# File dl/lib/dl/import.rb, line 55
def dlload(*libs)
handles = libs.collect{|lib|
case lib
when nil
nil
when Handle
lib
when Importer
lib.handlers
else
begin
DL.dlopen(lib)
rescue DLError
raise(DLError, "can't load #{lib}")
end
end
}.flatten()
@handler = CompositeHandler.new(handles)
@func_map = {}
@type_alias = {}
end
# File dl/lib/dl/import.rb, line 130
def extern(signature, *opts)
symname, ctype, argtype = parse_signature(signature, @type_alias)
opt = parse_bind_options(opts)
f = import_function(symname, ctype, argtype, opt[:call_type])
name = symname.gsub(/@.+/,'')
@func_map[name] = f
# define_method(name){|*args,&block| f.call(*args,&block)}
begin
/^(.+?):(\d+)/ =~ caller.first
file, line = $1, $2.to_i
rescue
file, line = __FILE__, __LINE__+3
end
module_eval(" def #{name}(*args, &block)
@func_map['#{name}'].call(*args,&block)
end
", file, line)
module_function(name)
f
end
# File dl/lib/dl/import.rb, line 212
def handler
@handler or raise "call dlload before importing symbols and functions"
end
# File dl/lib/dl/import.rb, line 224
def import_function(name, ctype, argtype, call_type = nil)
addr = handler.sym(name)
if( !addr )
raise(DLError, "cannot find the function: #{name}()")
end
Function.new(CFunc.new(addr, ctype, name, call_type || :cdecl), argtype)
end
# File dl/lib/dl/import.rb, line 216
def import_symbol(name)
addr = handler.sym(name)
if( !addr )
raise(DLError, "cannot find the symbol: #{name}")
end
CPtr.new(addr)
end
# File dl/lib/dl/import.rb, line 206
def import_value(ty, addr)
s = struct([ty + " value"])
ptr = s.new(addr)
return ptr
end
# File dl/lib/dl/import.rb, line 81
def sizeof(ty)
case ty
when String
ty = parse_ctype(ty, @type_alias).abs()
case ty
when TYPE_CHAR
return SIZEOF_CHAR
when TYPE_SHORT
return SIZEOF_SHORT
when TYPE_INT
return SIZEOF_INT
when TYPE_LONG
return SIZEOF_LONG
when TYPE_LONG_LONG
return SIZEOF_LONG_LON
when TYPE_FLOAT
return SIZEOF_FLOAT
when TYPE_DOUBLE
return SIZEOF_DOUBLE
when TYPE_VOIDP
return SIZEOF_VOIDP
else
raise(DLError, "unknown type: #{ty}")
end
when Class
if( ty.instance_methods().include?(:to_ptr) )
return ty.size()
end
end
return CPtr[ty].size()
end
# File dl/lib/dl/import.rb, line 182
def struct(signature)
tys, mems = parse_struct_signature(signature, @type_alias)
DL::CStructBuilder.create(CStruct, tys, mems)
end
# File dl/lib/dl/import.rb, line 77
def typealias(alias_type, orig_type)
@type_alias[alias_type] = orig_type
end
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