Mark non-private mapped files as external.

This commit is contained in:
Samuel Williams 2021-12-20 12:37:05 +13:00
parent da46b8d8e5
commit c86bcd434d
Notes: git 2021-12-21 08:26:08 +09:00
3 changed files with 23 additions and 20 deletions

View File

@ -27,20 +27,24 @@ RUBY_EXTERN size_t RUBY_IO_BUFFER_DEFAULT_SIZE;
enum rb_io_buffer_flags {
// The memory in the buffer is owned by someone else.
RB_IO_BUFFER_EXTERNAL = 0,
// More specifically, it means that someone else owns the buffer and we shouldn't try to resize it.
RB_IO_BUFFER_EXTERNAL = 1,
// The memory in the buffer is allocated internally.
RB_IO_BUFFER_INTERNAL = 1,
RB_IO_BUFFER_INTERNAL = 2,
// The memory in the buffer is mapped.
RB_IO_BUFFER_MAPPED = 2,
// A non-private mapping is marked as external.
RB_IO_BUFFER_MAPPED = 4,
// The buffer is locked and cannot be resized.
RB_IO_BUFFER_LOCKED = 16,
// More specifically, it means we can't change the base address or size.
// A buffer is typically locked before a system call that uses the data.
RB_IO_BUFFER_LOCKED = 32,
// The buffer mapping is private and will not impact other processes or the underlying file.
RB_IO_BUFFER_PRIVATE = 32,
RB_IO_BUFFER_PRIVATE = 64,
// The buffer is read-only and cannot be modified.
RB_IO_BUFFER_IMMUTABLE = 64
RB_IO_BUFFER_IMMUTABLE = 128
};
enum rb_io_buffer_endian {

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@ -83,6 +83,9 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
if (flags & RB_IO_BUFFER_PRIVATE) {
access |= FILE_MAP_COPY;
data->flags |= RB_IO_BUFFER_PRIVATE;
} else {
// This buffer refers to external data.
data->flags |= RB_IO_BUFFER_EXTERNAL;
}
void *base = MapViewOfFile(mapping, access, (DWORD)(offset >> 32), (DWORD)(offset & 0xFFFFFFFF), size);
@ -107,6 +110,8 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
data->flags |= RB_IO_BUFFER_PRIVATE;
}
else {
// This buffer refers to external data.
data->flags |= RB_IO_BUFFER_EXTERNAL;
access |= MAP_SHARED;
}
@ -572,7 +577,7 @@ rb_io_buffer_external_p(VALUE self)
struct rb_io_buffer *data = NULL;
TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
return data->flags & (RB_IO_BUFFER_INTERNAL | RB_IO_BUFFER_MAPPED) ? Qfalse : Qtrue;
return data->flags & RB_IO_BUFFER_EXTERNAL ? Qtrue : Qfalse;
}
static VALUE
@ -611,12 +616,6 @@ rb_io_buffer_immutable_p(VALUE self)
return data->flags & RB_IO_BUFFER_IMMUTABLE ? Qtrue : Qfalse;
}
static int
io_buffer_external_p(enum rb_io_buffer_flags flags)
{
return !(flags & (RB_IO_BUFFER_INTERNAL | RB_IO_BUFFER_MAPPED));
}
VALUE
rb_io_buffer_lock(VALUE self)
{
@ -858,7 +857,7 @@ rb_io_buffer_resize(VALUE self, size_t size)
return;
}
if (io_buffer_external_p(data->flags)) {
if (data->flags & RB_IO_BUFFER_EXTERNAL) {
rb_raise(rb_eIOBufferMutationError, "Cannot resize external buffer!");
}

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@ -18,14 +18,14 @@ class TestIOBuffer < Test::Unit::TestCase
end
def test_flags
assert_equal 0, IO::Buffer::EXTERNAL
assert_equal 1, IO::Buffer::INTERNAL
assert_equal 2, IO::Buffer::MAPPED
assert_equal 1, IO::Buffer::EXTERNAL
assert_equal 2, IO::Buffer::INTERNAL
assert_equal 4, IO::Buffer::MAPPED
assert_equal 16, IO::Buffer::LOCKED
assert_equal 32, IO::Buffer::PRIVATE
assert_equal 32, IO::Buffer::LOCKED
assert_equal 64, IO::Buffer::PRIVATE
assert_equal 64, IO::Buffer::IMMUTABLE
assert_equal 128, IO::Buffer::IMMUTABLE
end
def test_endian