Module MessageWrapper.Segment
Contents
Instructions: Use this module in your project
In the IDE (CLion, Visual Studio Code, Xcode, etc.) you use for your DkSDK project:
Add the following to your project's
dependencies/CMakeLists.txt
:DkSDKProject_DeclareAvailable(capnp CONSTRAINT "= 3.5.0" FINDLIBS capnp capnp.unix) DkSDKProject_MakeAvailable(capnp)
Add the
Findlib::capnp
library to any desired targets insrc/*/CMakeLists.txt
:target_link_libraries(YourPackage_YourLibraryName # ... existing libraries, if any ... Findlib::capnp)
Click your IDE's
Build
button
Not using DkSDK?
FIRST, do one or all of the following:
Run:
opam install capnp.3.5.0
Edit your
dune-project
and add:(package (name YourExistingPackage) (depends ; ... existing dependenices ... (capnp (>= 3.5.0))))
Then run:
dune build *.opam # if this fails, run: dune build
Edit your
<package>.opam
file and add:depends: [ # ... existing dependencies ... "capnp" {>= "3.5.0"} ]
Then run:
opam install . --deps-only
FINALLY, add the capnp
library to any desired (library)
and/or (executable)
targets in your **/dune
files:
(library
(name YourLibrary)
; ... existing library options ...
(libraries
; ... existing libraries ...
capnp))
(executable
(name YourExecutable)
; ... existing executable options ...
(libraries
; ... existing libraries ...
capnp))
include
MessageSig.SEGMENT
type
storage_t
storage_t
is the type of the underlying storage associated with this
segment (e.g. "bytes").
type
``-'cap t
'cap t
is the type of a message segment. The 'cap
annotation is type
ro
for read-only segments, and type rw
for read/write segments.
val
alloc : ``int
->
MessageSig.rw
t
alloc size
allocates a new zero-filled message segment of at least
size
bytes, raising an exception if storage cannot be allocated.
val
release :
'cap
t
->
unit
release s
immediately releases the storage associated with message
segment s
, potentially making the storage available for future
allocations. After releasing a storage segment, the behavior of the
accessor functions is undefined.
val
length :
'cap
t
->
int
length s
determines the length of this message segment.
val
readonly :
'cap
t
->
MessageSig.ro
t
readonly s
obtains a view of segment s
which is read-only qualified.
val
of_storage :
storage_t
->
MessageSig.rw
t
of_storage storage
constructs a read/write segment which uses the
given storage
for the underlying storage media.
to_storage s
retrieves the underlying storage media associated with
segment s
.
get_uintXX s ofs
reads an unsigned integer of the specified width,
starting at byte offset ofs
within message segment s
.
val
get_uint8 :
'cap
t
->
``int
->
int
val
get_uint16 :
'cap
t
->
``int
->
int
val
get_uint32 :
'cap
t
->
``int
->
Stdint.Uint32.t
val
get_uint64 :
'cap
t
->
``int
->
Stdint.Uint64.t
get_intXX s ofs
reads a signed integer of the specified width,
starting at byte offset ofs
within message segment s
.
val
get_int8 :
'cap
t
->
``int
->
int
val
get_int16 :
'cap
t
->
``int
->
int
val
get_int32 :
'cap
t
->
``int
->
Stdlib.Int32.t
val
get_int64 :
'cap
t
->
``int
->
Stdlib.Int64.t
set_uintXX s ofs val
writes the value of the width-restricted unsigned
integer val
into read/write-qualified message segment s
, starting at
byte offset ofs
.
val
set_uint8 :
MessageSig.rw
t
->
``int
->
``int
->
unit
val
set_uint16 :
MessageSig.rw
t
->
``int
->
``int
->
unit
val
set_uint32 :
MessageSig.rw
t
->
``int
->
Stdint.Uint32.t
->
unit
val
set_uint64 :
MessageSig.rw
t
->
``int
->
Stdint.Uint64.t
->
unit
set_intXX s ofs val
writes the value of the width-restricted signed
integer val
into read/write-qualified message segment s
, starting at
byte offset ofs
.
val
set_int8 :
MessageSig.rw
t
->
``int
->
``int
->
unit
val
set_int16 :
MessageSig.rw
t
->
``int
->
``int
->
unit
val
set_int32 :
MessageSig.rw
t
->
``int
->
Stdlib.Int32.t
->
unit
val
set_int64 :
MessageSig.rw
t
->
``int
->
Stdlib.Int64.t
->
unit
val
blit : ``src:
'cap
t
->
``src_pos:int
->
``dst:
MessageSig.rw
t
->
``dst_pos:int
->
``len:int
->
unit
blit ~src ~src_pos ~dst ~dst_pos ~len
transfers len
bytes from
position dst_pos
in dst
to position src_pos
in pos
. The blit
operation shall work correctly even for the case of overlapping buffers.
val
blit_to_bytes : ``src:
'cap
t
->
``src_pos:int
->
``dst:
Stdlib.Bytes.t
->
``dst_pos:int
->
``len:int
->
unit
As blit
, but the destination is a bytes
buffer.
val
blit_from_string : ``src:string
->
``src_pos:int
->
``dst:
MessageSig.rw
t
->
``dst_pos:int
->
``len:int
->
unit
As blit
, but the source is a string
buffer.
val
zero_out :
MessageSig.rw
t
->
``pos:int
->
``len:int
->
unit
zero_out segment ~pos ~len
sets len
bytes of the segment to zero,
beginning at byte offset pos
.