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|
#
# This file is part of ruby-ffi.
# For licensing, see LICENSE.SPECS
#
require File.expand_path(File.join(File.dirname(__FILE__), "spec_helper"))
describe "Struct aligns fields correctly" do
it "char, followed by an int" do
class CIStruct < FFI::Struct
layout :c => :char, :i => :int
end
expect(CIStruct.size).to eq(8)
end
it "short, followed by an int" do
class SIStruct < FFI::Struct
layout :s => :short, :i => :int
end
expect(SIStruct.size).to eq(8)
end
it "int, followed by an int" do
class IIStruct < FFI::Struct
layout :i1 => :int, :i => :int
end
expect(IIStruct.size).to eq(8)
end
it "long long, followed by an int" do
class LLIStruct < FFI::Struct
layout :l => :long_long, :i => :int
end
expect(LLIStruct.size).to eq(FFI::TYPE_UINT64.alignment == 4 ? 12 : 16)
end
end
describe "Struct tests" do
StructTypes = {
's8' => :char,
's16' => :short,
's32' => :int,
's64' => :long_long,
'long' => :long,
'f32' => :float,
'f64' => :double
}
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
attach_function :ptr_ret_pointer, [ :pointer, :int], :string
begin
attach_function :ptr_ret_int32_t, [ :pointer, :int ], :int
rescue FFI::NotFoundError
# NetBSD uses #define instead of typedef for these
attach_function :ptr_ret_int32_t, :ptr_ret___int32_t, [ :pointer, :int ], :int
end
attach_function :ptr_from_address, [ :ulong ], :pointer
attach_function :string_equals, [ :string, :string ], :int
[ 's8', 's16', 's32', 's64', 'f32', 'f64', 'long' ].each do |t|
attach_function "struct_align_#{t}", [ :pointer ], StructTypes[t]
end
end
class PointerMember < FFI::Struct
layout :pointer, :pointer
end
class StringMember < FFI::Struct
layout :string, :string
end
it "Struct#[:pointer]" do
magic = 0x12345678
mp = FFI::MemoryPointer.new :long
mp.put_long(0, magic)
smp = FFI::MemoryPointer.new :pointer
smp.put_pointer(0, mp)
s = PointerMember.new smp
expect(s[:pointer]).to eq(mp)
end
it "Struct#[:pointer].nil? for NULL value" do
magic = 0x12345678
mp = FFI::MemoryPointer.new :long
mp.put_long(0, magic)
smp = FFI::MemoryPointer.new :pointer
smp.put_pointer(0, nil)
s = PointerMember.new smp
expect(s[:pointer].null?).to be true
end
it "Struct#[:pointer]=" do
magic = 0x12345678
mp = FFI::MemoryPointer.new :long
mp.put_long(0, magic)
smp = FFI::MemoryPointer.new :pointer
s = PointerMember.new smp
s[:pointer] = mp
expect(smp.get_pointer(0)).to eq(mp)
end
it "Struct#[:pointer]=struct" do
smp = FFI::MemoryPointer.new :pointer
s = PointerMember.new smp
expect { s[:pointer] = s }.not_to raise_error Exception
expect { s[:pointer].nil? }.not_to raise_error Exception
end
it "Struct#[:pointer]=nil" do
smp = FFI::MemoryPointer.new :pointer
s = PointerMember.new smp
s[:pointer] = nil
expect(smp.get_pointer(0)).to be_null
end
it "Struct#[:string]" do
magic = "test"
mp = FFI::MemoryPointer.new 1024
mp.put_string(0, magic)
smp = FFI::MemoryPointer.new :pointer
smp.put_pointer(0, mp)
s = StringMember.new smp
expect(s[:string]).to eq(magic)
end
it "Struct#[:string].nil? for NULL value" do
smp = FFI::MemoryPointer.new :pointer
smp.put_pointer(0, nil)
s = StringMember.new smp
expect(s[:string]).to be_nil
end
it "Struct#layout works with :name, :type pairs" do
class PairLayout < FFI::Struct
layout :a, :int, :b, :long_long
end
ll_off = (FFI::TYPE_UINT64.alignment == 4 ? 4 : 8)
expect(PairLayout.size).to eq((ll_off + 8))
mp = FFI::MemoryPointer.new(PairLayout.size)
s = PairLayout.new mp
s[:a] = 0x12345678
expect(mp.get_int(0)).to eq(0x12345678)
s[:b] = 0xfee1deadbeef
expect(mp.get_int64(ll_off)).to eq(0xfee1deadbeef)
end
it "Struct#layout works with :name, :type, offset tuples" do
class PairLayout < FFI::Struct
layout :a, :int, 0, :b, :long_long, 4
end
expect(PairLayout.size).to eq((FFI::TYPE_UINT64.alignment == 4 ? 12 : 16))
mp = FFI::MemoryPointer.new(PairLayout.size)
s = PairLayout.new mp
s[:a] = 0x12345678
expect(mp.get_int(0)).to eq(0x12345678)
s[:b] = 0xfee1deadbeef
expect(mp.get_int64(4)).to eq(0xfee1deadbeef)
end
it "Struct#layout works with mixed :name,:type and :name,:type,offset" do
class MixedLayout < FFI::Struct
layout :a, :int, :b, :long_long, 4
end
expect(MixedLayout.size).to eq((FFI::TYPE_UINT64.alignment == 4 ? 12 : 16))
mp = FFI::MemoryPointer.new(MixedLayout.size)
s = MixedLayout.new mp
s[:a] = 0x12345678
expect(mp.get_int(0)).to eq(0x12345678)
s[:b] = 0xfee1deadbeef
expect(mp.get_int64(4)).to eq(0xfee1deadbeef)
end
rb_maj, rb_min = RUBY_VERSION.split('.')
if rb_maj.to_i >= 1 && rb_min.to_i >= 9 || RUBY_PLATFORM =~ /java/
it "Struct#layout withs with a hash of :name => type" do
class HashLayout < FFI::Struct
layout :a => :int, :b => :long_long
end
ll_off = (FFI::TYPE_UINT64.alignment == 4 ? 4 : 8)
expect(HashLayout.size).to eq(ll_off + 8)
mp = FFI::MemoryPointer.new(HashLayout.size)
s = HashLayout.new mp
s[:a] = 0x12345678
expect(mp.get_int(0)).to eq(0x12345678)
s[:b] = 0xfee1deadbeef
expect(mp.get_int64(ll_off)).to eq(0xfee1deadbeef)
end
end
it "subclass overrides initialize without calling super" do
class InitializeWithoutSuper < FFI::Struct
layout :a, :int, :b, :long_long, :d, [:double, 2]
def initialize(a, b)
self[:a] = a
self[:b] = b
self[:d][0] = 1.2
self[:d][1] = 3.4
end
end
s = InitializeWithoutSuper.new(0x1eefbeef, 0xdeadcafebabe)
expect(s[:a]).to eq(0x1eefbeef)
expect(s[:b]).to eq(0xdeadcafebabe)
end
it "Can use Struct subclass as parameter type" do
expect(module StructParam
extend FFI::Library
ffi_lib TestLibrary::PATH
class TestStruct < FFI::Struct
layout :c, :char
end
attach_function :struct_field_s8, [ TestStruct.in ], :char
end).to be_an_instance_of FFI::Function
end
it "Can use Struct subclass as IN parameter type" do
expect(module StructParam2
extend FFI::Library
ffi_lib TestLibrary::PATH
class TestStruct < FFI::Struct
layout :c, :char
end
attach_function :struct_field_s8, [ TestStruct.in ], :char
end).to be_an_instance_of FFI::Function
end
it "Can use Struct subclass as OUT parameter type" do
expect(module StructParam3
extend FFI::Library
ffi_lib TestLibrary::PATH
class TestStruct < FFI::Struct
layout :c, :char
end
attach_function :struct_field_s8, [ TestStruct.out ], :char
end).to be_an_instance_of FFI::Function
end
it "can be passed directly as a :pointer parameter" do
class TestStruct < FFI::Struct
layout :i, :int
end
s = TestStruct.new
s[:i] = 0x12
expect(LibTest.ptr_ret_int32_t(s, 0)).to eq(0x12)
end
it ":char member aligned correctly" do
class AlignChar < FFI::Struct
layout :c, :char, :v, :char
end
s = AlignChar.new
s[:v] = 0x12
expect(LibTest.struct_align_s8(s.pointer)).to eq(0x12)
end
it ":short member aligned correctly" do
class AlignShort < FFI::Struct
layout :c, :char, :v, :short
end
s = AlignShort.alloc_in
s[:v] = 0x1234
expect(LibTest.struct_align_s16(s.pointer)).to eq(0x1234)
end
it ":int member aligned correctly" do
class AlignInt < FFI::Struct
layout :c, :char, :v, :int
end
s = AlignInt.alloc_in
s[:v] = 0x12345678
expect(LibTest.struct_align_s32(s.pointer)).to eq(0x12345678)
end
it ":long_long member aligned correctly" do
class AlignLongLong < FFI::Struct
layout :c, :char, :v, :long_long
end
s = AlignLongLong.alloc_in
s[:v] = 0x123456789abcdef0
expect(LibTest.struct_align_s64(s.pointer)).to eq(0x123456789abcdef0)
end
it ":long member aligned correctly" do
class AlignLong < FFI::Struct
layout :c, :char, :v, :long
end
s = AlignLong.alloc_in
s[:v] = 0x12345678
expect(LibTest.struct_align_long(s.pointer)).to eq(0x12345678)
end
it ":float member aligned correctly" do
class AlignFloat < FFI::Struct
layout :c, :char, :v, :float
end
s = AlignFloat.alloc_in
s[:v] = 1.23456
expect((LibTest.struct_align_f32(s.pointer) - 1.23456).abs).to be < 0.00001
end
it ":double member aligned correctly" do
class AlignDouble < FFI::Struct
layout :c, :char, :v, :double
end
s = AlignDouble.alloc_in
s[:v] = 1.23456789
expect((LibTest.struct_align_f64(s.pointer) - 1.23456789).abs).to be < 0.00000001
end
it ":ulong, :pointer struct" do
class ULPStruct < FFI::Struct
layout :ul, :ulong, :p, :pointer
end
s = ULPStruct.alloc_in
s[:ul] = 0xdeadbeef
s[:p] = LibTest.ptr_from_address(0x12345678)
expect(s.pointer.get_ulong(0)).to eq(0xdeadbeef)
end
def test_num_field(type, v)
klass = Class.new(FFI::Struct)
klass.layout :v, type, :dummy, :long
s = klass.new
s[:v] = v
expect(s.pointer.send("get_#{type.to_s}", 0)).to eq(v)
s.pointer.send("put_#{type.to_s}", 0, 0)
expect(s[:v]).to eq(0)
end
def self.int_field_test(type, values)
values.each do |v|
it "#{type} field r/w (#{v.to_s(16)})" do
test_num_field(type, v)
end
end
end
int_field_test(:char, [ 0, 127, -128, -1 ])
int_field_test(:uchar, [ 0, 0x7f, 0x80, 0xff ])
int_field_test(:short, [ 0, 0x7fff, -0x8000, -1 ])
int_field_test(:ushort, [ 0, 0x7fff, 0x8000, 0xffff ])
int_field_test(:int, [ 0, 0x7fffffff, -0x80000000, -1 ])
int_field_test(:uint, [ 0, 0x7fffffff, 0x80000000, 0xffffffff ])
int_field_test(:long_long, [ 0, 0x7fffffffffffffff, -0x8000000000000000, -1 ])
int_field_test(:ulong_long, [ 0, 0x7fffffffffffffff, 0x8000000000000000, 0xffffffffffffffff ])
if FFI::Platform::LONG_SIZE == 32
int_field_test(:long, [ 0, 0x7fffffff, -0x80000000, -1 ])
int_field_test(:ulong, [ 0, 0x7fffffff, 0x80000000, 0xffffffff ])
else
int_field_test(:long, [ 0, 0x7fffffffffffffff, -0x8000000000000000, -1 ])
int_field_test(:ulong, [ 0, 0x7fffffffffffffff, 0x8000000000000000, 0xffffffffffffffff ])
end
it ":float field r/w" do
klass = Class.new(FFI::Struct)
klass.layout :v, :float, :dummy, :long
s = klass.new
value = 1.23456
s[:v] = value
expect((s.pointer.get_float(0) - value).abs).to be < 0.0001
end
it ":double field r/w" do
klass = Class.new(FFI::Struct)
klass.layout :v, :double, :dummy, :long
s = klass.new
value = 1.23456
s[:v] = value
expect((s.pointer.get_double(0) - value).abs).to be < 0.0001
end
module EnumFields
extend FFI::Library
TestEnum = enum :test_enum, [:c1, 10, :c2, 20, :c3, 30, :c4, 40]
class TestStruct < FFI::Struct
layout :a, :int, :c, :test_enum,
:d, [ TestEnum, TestEnum.symbols.length ]
end
end
it ":enum field r/w" do
s = EnumFields::TestStruct.new
s[:c] = :c3
expect(s.pointer.get_uint(FFI::Type::INT32.size)).to eq(30)
expect(s[:c]).to eq(:c3)
end
it "array of :enum field" do
s = EnumFields::TestStruct.new
EnumFields::TestEnum.symbols.each_with_index do |val, i|
s[:d][i] = val
end
EnumFields::TestEnum.symbols.each_with_index do |val, i|
expect(s.pointer.get_uint(FFI::Type::INT32.size * (2 + i))).to eq(EnumFields::TestEnum[val])
end
s[:d].each_with_index do |val, i|
expect(val).to eq(EnumFields::TestEnum.symbols[i])
end
end
module CallbackMember
extend FFI::Library
ffi_lib TestLibrary::PATH
callback :add, [ :int, :int ], :int
callback :sub, [ :int, :int ], :int
class TestStruct < FFI::Struct
layout :add, :add,
:sub, :sub
end
attach_function :struct_call_add_cb, [TestStruct.in, :int, :int], :int
attach_function :struct_call_sub_cb, [TestStruct.in, :int, :int], :int
end
it "Can have CallbackInfo struct field" do
s = CallbackMember::TestStruct.new
add_proc = lambda { |a, b| a+b }
sub_proc = lambda { |a, b| a-b }
s[:add] = add_proc
s[:sub] = sub_proc
expect(CallbackMember.struct_call_add_cb(s, 40, 2)).to eq(42)
expect(CallbackMember.struct_call_sub_cb(s, 44, 2)).to eq(42)
end
it "Can return its members as a list" do
class TestStruct < FFI::Struct
layout :a, :int, :b, :int, :c, :int
end
expect(TestStruct.members).to include(:a, :b, :c)
end
it "Can return its instance members and values as lists" do
class TestStruct < FFI::Struct
layout :a, :int, :b, :int, :c, :int
end
s = TestStruct.new
expect(s.members).to include(:a, :b, :c)
s[:a] = 1
s[:b] = 2
s[:c] = 3
expect(s.values).to include(1, 2, 3)
end
it 'should return an ordered field/offset pairs array' do
class TestStruct < FFI::Struct
layout :a, :int, :b, :int, :c, :int
end
s = TestStruct.new
expect(s.offsets).to eq([[:a, 0], [:b, 4], [:c, 8]])
expect(TestStruct.offsets).to eq([[:a, 0], [:b, 4], [:c, 8]])
end
it "Struct#offset_of returns offset of field within struct" do
class TestStruct < FFI::Struct
layout :a, :int, :b, :int, :c, :int
end
expect(TestStruct.offset_of(:a)).to eq(0)
expect(TestStruct.offset_of(:b)).to eq(4)
expect(TestStruct.offset_of(:c)).to eq(8)
end
end
describe FFI::Struct, ".layout" do
module FFISpecs
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
begin
attach_function :ptr_ret_int32_t, [ :pointer, :int ], :int
rescue FFI::NotFoundError
# NetBSD uses #define instead of typedef for these
attach_function :ptr_ret_int32_t, :ptr_ret___int32_t, [ :pointer, :int ], :int
end
end
end
describe "when derived class is not assigned to any constant" do
it "resolves a built-in type" do
klass = Class.new FFI::Struct
klass.layout :number, :int
instance = klass.new
instance[:number] = 0xA1
expect(FFISpecs::LibTest.ptr_ret_int32_t(instance, 0)).to eq(0xA1)
end
end
describe "when derived class is assigned to a constant" do
it "resolves a built-in type" do
class FFISpecs::TestStruct < FFI::Struct
layout :number, :int
end
instance = FFISpecs::TestStruct.new
instance[:number] = 0xA1
expect(FFISpecs::LibTest.ptr_ret_int32_t(instance, 0)).to eq(0xA1)
end
it "resolves a type from the enclosing module" do
module FFISpecs::LibTest
typedef :uint, :custom_int
class TestStruct < FFI::Struct
layout :number, :custom_int
end
end
instance = FFISpecs::LibTest::TestStruct.new
instance[:number] = 0xA1
expect(FFISpecs::LibTest.ptr_ret_int32_t(instance, 0)).to eq(0xA1)
end
end
end
describe FFI::Struct, ' with a nested struct field' do
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
class NestedStruct < FFI::Struct
layout :i, :int
end
class ContainerStruct < FFI::Struct
layout :first, :char, :ns, NestedStruct
end
attach_function :struct_align_nested_struct, [ :pointer ], :int
attach_function :struct_make_container_struct, [ :int ], :pointer
end
before do
@cs = LibTest::ContainerStruct.new
end
it 'should align correctly nested struct field' do
@cs[:ns][:i] = 123
expect(LibTest.struct_align_nested_struct(@cs.to_ptr)).to eq(123)
end
it 'should correctly calculate Container size (in bytes)' do
expect(LibTest::ContainerStruct.size).to eq(8)
end
it 'should return a Struct object when the field is accessed' do
expect(@cs[:ns].is_a?(FFI::Struct)).to be true
end
it 'should read a value from memory' do
@cs = LibTest::ContainerStruct.new(LibTest.struct_make_container_struct(123))
expect(@cs[:ns][:i]).to eq(123)
end
it 'should write a value to memory' do
@cs = LibTest::ContainerStruct.new(LibTest.struct_make_container_struct(123))
@cs[:ns][:i] = 456
expect(LibTest.struct_align_nested_struct(@cs.to_ptr)).to eq(456)
end
it 'should be able to assign struct instance to nested field' do
cs = LibTest::ContainerStruct.new(LibTest.struct_make_container_struct(123))
ns = LibTest::NestedStruct.new
ns[:i] = 567
cs[:ns] = ns
expect(cs[:ns][:i]).to eq(567)
expect(LibTest.struct_align_nested_struct(cs.to_ptr)).to eq(567)
end
end
describe FFI::Struct, ' with a nested array of structs' do
module InlineArrayOfStructs
extend FFI::Library
ffi_lib TestLibrary::PATH
class NestedStruct < FFI::Struct
layout :i, :int
end
class ContainerStruct < FFI::Struct
layout :first, :char, :ns, [ NestedStruct, 1 ]
end
attach_function :struct_align_nested_struct, [ :pointer ], :int
attach_function :struct_make_container_struct, [ :int ], :pointer
end
before do
@cs = InlineArrayOfStructs::ContainerStruct.new
end
it 'should align correctly nested struct field' do
@cs[:ns][0][:i] = 123
expect(InlineArrayOfStructs.struct_align_nested_struct(@cs.to_ptr)).to eq(123)
end
it 'should correctly calculate Container size (in bytes)' do
expect(InlineArrayOfStructs::ContainerStruct.size).to eq(8)
end
it 'should return a Struct object when the field is accessed' do
expect(@cs[:ns][0].is_a?(FFI::Struct)).to be true
end
it 'should read a value from memory' do
@cs = InlineArrayOfStructs::ContainerStruct.new(InlineArrayOfStructs.struct_make_container_struct(123))
expect(@cs[:ns][0][:i]).to eq(123)
end
it 'should write a value to memory' do
@cs = InlineArrayOfStructs::ContainerStruct.new(InlineArrayOfStructs.struct_make_container_struct(123))
@cs[:ns][0][:i] = 456
expect(InlineArrayOfStructs.struct_align_nested_struct(@cs.to_ptr)).to eq(456)
end
it 'should support Enumerable#each' do
@cs = InlineArrayOfStructs::ContainerStruct.new(InlineArrayOfStructs.struct_make_container_struct(123))
ints = []
@cs[:ns].each { |s| ints << s[:i] }
expect(ints[0]).to eq(123)
end
end
describe FFI::Struct, ' by value' do
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
class S8S32 < FFI::Struct
layout :s8, :char, :s32, :int
end
class StructString < FFI::Struct
layout :bytes, :string, :len, :int
end
attach_function :struct_return_s8s32, [ ], S8S32.by_value
attach_function :struct_s8s32_set, [ :char, :int ], S8S32.by_value
attach_function :struct_s8s32_get_s8, [ S8S32.by_value ], :char
attach_function :struct_s8s32_get_s32, [ S8S32.by_value ], :int
attach_function :struct_s8s32_s32_ret_s32, [ S8S32.by_value, :int ], :int
attach_function :struct_s8s32_s64_ret_s64, [ S8S32.by_value, :long_long ], :long_long
attach_function :struct_s8s32_ret_s8s32, [ S8S32.by_value ], S8S32.by_value
attach_function :struct_s32_ptr_s32_s8s32_ret_s32, [ :int, :pointer, :int, S8S32.by_value ], :int
attach_function :struct_varargs_ret_struct_string, [ :int, :varargs ], StructString.by_value
end
it 'return using pre-set values' do
s = LibTest.struct_return_s8s32
expect(s[:s8]).to eq(0x7f)
expect(s[:s32]).to eq(0x12345678)
end
it 'return using passed in values' do
s = LibTest.struct_s8s32_set(123, 456789)
expect(s[:s8]).to eq(123)
expect(s[:s32]).to eq(456789)
end
it 'parameter' do
s = LibTest::S8S32.new
s[:s8] = 0x12
s[:s32] = 0x34567890
expect(LibTest.struct_s8s32_get_s8(s)).to eq(0x12)
expect(LibTest.struct_s8s32_get_s32(s)).to eq(0x34567890)
end
it 'parameter with following s32' do
s = LibTest::S8S32.new
s[:s8] = 0x12
s[:s32] = 0x34567890
expect(LibTest.struct_s8s32_s32_ret_s32(s, 0x1eefdead)).to eq(0x1eefdead)
end
# it 'parameter with following s64' do
# s = LibTest::S8S64.new
# s[:s8] = 0x12
# s[:s64] = 0x34567890
#
#
# LibTest.struct_s8s64_s64_ret_s64(s, 0x1eefdead1eefdead).should == 0x1eefdead1eefdead
# end
it 'parameter with preceding s32,ptr,s32' do
s = LibTest::S8S32.new
s[:s8] = 0x12
s[:s32] = 0x34567890
out = LibTest::S8S32.new
expect(LibTest.struct_s32_ptr_s32_s8s32_ret_s32(0x1000000, out, 0x1eafbeef, s)).to eq(0x34567890)
expect(out[:s8]).to eq(s[:s8])
expect(out[:s32]).to eq(s[:s32])
end
it 'parameter with preceding s32,string,s32' do
s = LibTest::S8S32.new
s[:s8] = 0x12
s[:s32] = 0x34567890
out = 0.chr * 32
expect(LibTest.struct_s32_ptr_s32_s8s32_ret_s32(0x1000000, out, 0x1eafbeef, s)).to eq(0x34567890)
end
it 'parameter, returning struct by value' do
s = LibTest::S8S32.new
s[:s8] = 0x12
s[:s32] = 0x34567890
ret = LibTest.struct_s8s32_ret_s8s32(s)
expect(ret[:s8]).to eq(s[:s8])
expect(ret[:s32]).to eq(s[:s32])
end
it 'varargs returning a struct' do
string = "test"
s = LibTest.struct_varargs_ret_struct_string(4, :string, string)
expect(s[:len]).to eq(string.length)
expect(s[:bytes]).to eq(string)
end
end
describe FFI::Struct, ' with an array field' do
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
class StructWithArray < FFI::Struct
layout :first, :char, :a, [:int, 5]
end
attach_function :struct_make_struct_with_array, [:int, :int, :int, :int, :int], :pointer
attach_function :struct_field_array, [:pointer], :pointer
end
before do
@s = LibTest::StructWithArray.new
end
it 'should correctly calculate StructWithArray size (in bytes)' do
expect(LibTest::StructWithArray.size).to eq(24)
end
it 'should read values from memory' do
@s = LibTest::StructWithArray.new(LibTest.struct_make_struct_with_array(0, 1, 2, 3, 4))
expect(@s[:a].to_a).to eq([0, 1, 2, 3, 4])
end
# it 'should cache array object for successive calls' do
# @s[:a].object_id.should == @s[:a].object_id
# end
it 'should return the number of elements in the array field' do
@s = LibTest::StructWithArray.new(LibTest.struct_make_struct_with_array(0, 1, 2, 3, 4))
expect(@s[:a].size).to eq(5)
end
it 'should allow iteration through the array elements' do
@s = LibTest::StructWithArray.new(LibTest.struct_make_struct_with_array(0, 1, 2, 3, 4))
@s[:a].each_with_index { |elem, i| expect(elem).to eq(i) }
end
it 'should return the pointer to the array' do
@s = LibTest::StructWithArray.new(LibTest.struct_make_struct_with_array(0, 1, 2, 3, 4))
expect(@s[:a].to_ptr).to eq(LibTest::struct_field_array(@s.to_ptr))
end
end
describe 'BuggedStruct' do
module LibTest
extend FFI::Library
ffi_lib TestLibrary::PATH
class BuggedStruct < FFI::Struct
layout :visible, :uchar,
:x, :uint,
:y, :uint,
:rx, :short,
:ry, :short,
:order, :uchar,
:size, :uchar
end
attach_function :bugged_struct_size, [], :uint
end
it 'should return its correct size' do
expect(LibTest::BuggedStruct.size).to eq(LibTest.bugged_struct_size)
end
it "offsets within struct should be correct" do
expect(LibTest::BuggedStruct.offset_of(:visible)).to eq(0)
expect(LibTest::BuggedStruct.offset_of(:x)).to eq(4)
expect(LibTest::BuggedStruct.offset_of(:y)).to eq(8)
expect(LibTest::BuggedStruct.offset_of(:rx)).to eq(12)
expect(LibTest::BuggedStruct.offset_of(:ry)).to eq(14)
expect(LibTest::BuggedStruct.offset_of(:order)).to eq(16)
expect(LibTest::BuggedStruct.offset_of(:size)).to eq(17)
end
it 'should return correct field/offset pairs' do
expect(LibTest::BuggedStruct.offsets.sort do |a, b|
a[1] <=> b[1]
end).to eq([[:visible, 0], [:x, 4], [:y, 8], [:rx, 12], [:ry, 14], [:order, 16], [:size, 17]])
end
end
describe "Struct allocation" do
it "MemoryPointer.new(Struct, 2)" do
class S < FFI::Struct
layout :i, :uint
end
p = FFI::MemoryPointer.new(S, 2)
expect(p.total).to eq(8)
expect(p.type_size).to eq(4)
p.put_uint(4, 0xdeadbeef)
expect(S.new(p[1])[:i]).to eq(0xdeadbeef)
expect(p[1].address).to eq((p[0].address + 4))
end
it "Buffer.new(Struct, 2)" do
class S < FFI::Struct
layout :i, :uint
end
p = FFI::Buffer.new(S, 2)
expect(p.total).to eq(8)
expect(p.type_size).to eq(4)
p.put_uint(4, 0xdeadbeef)
expect(S.new(p[1])[:i]).to eq(0xdeadbeef)
end
it "null? should be true when initialized with NULL pointer" do
class S < FFI::Struct
layout :i, :uint
end
expect(S.new(FFI::Pointer::NULL)).to be_null
end
it "null? should be false when initialized with non-NULL pointer" do
class S < FFI::Struct
layout :i, :uint
end
expect(S.new(FFI::MemoryPointer.new(S))).not_to be_null
end
it "supports :bool as a struct member" do
expect do
c = Class.new(FFI::Struct) do
layout :b, :bool
end
struct = c.new
struct[:b] = ! struct[:b]
end.not_to raise_error Exception
end
end
describe "variable-length arrays" do
it "zero length array should be accepted as last field" do
expect {
Class.new(FFI::Struct) do
layout :count, :int, :data, [ :char, 0 ]
end
}.not_to raise_error Exception
end
it "zero length array before last element should raise error" do
expect {
Class.new(FFI::Struct) do
layout :data, [ :char, 0 ], :count, :int
end
}.to raise_error
end
it "can access elements of array" do
struct_class = Class.new(FFI::Struct) do
layout :count, :int, :data, [ :long, 0 ]
end
s = struct_class.new(FFI::MemoryPointer.new(1024))
s[:data][0] = 0x1eadbeef
s[:data][1] = 0x12345678
expect(s[:data][0]).to eq(0x1eadbeef)
expect(s[:data][1]).to eq(0x12345678)
end
it "non-variable length array is bounds checked" do
struct_class = Class.new(FFI::Struct) do
layout :count, :int, :data, [ :long, 1 ]
end
s = struct_class.new(FFI::MemoryPointer.new(1024))
s[:data][0] = 0x1eadbeef
expect { s[:data][1] = 0x12345678 }.to raise_error
expect(s[:data][0]).to eq(0x1eadbeef)
expect { expect(s[:data][1]).to == 0x12345678 }.to raise_error
end
end
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