Merge pull request #308 from reynir/copy

Deprecate copy

lib/cstruct.ml

@@ -53,7 +53,7 @@ let err_of_bigarray t = err "Cstruct.of_bigarray off=%d len=%d" t
 let err_sub t = err "Cstruct.sub: %a off=%d len=%d" pp_t t
 let err_shift t = err "Cstruct.shift %a %d" pp_t t
 let err_shiftv n = err "Cstruct.shiftv short by %d" n
-let err_copy t = err "Cstruct.copy %a off=%d len=%d" pp_t t
+let err_copy_to_string caller t = err "Cstruct.%s %a off=%d len=%d" caller pp_t t
 let err_to_hex_string t = err "Cstruct.to_hex_string %a off=%d len=%d" pp_t t
 let err_blit_src src dst =
   err "Cstruct.blit src=%a dst=%a src-off=%d len=%d" pp_t src pp_t dst
@@ -200,15 +200,17 @@ external unsafe_compare_bigstring : buffer -> int -> buffer -> int -> int -> int
 
 external unsafe_fill_bigstring : buffer -> int -> int -> int -> unit = "caml_fill_bigstring" [@@noalloc]
 
-let copy src srcoff len =
+let copy_to_string caller src srcoff len =
   if len < 0 || srcoff < 0 || src.len - srcoff < len then
-    err_copy src srcoff len
+    err_copy_to_string caller src srcoff len
   else
     let b = Bytes.create len in
     unsafe_blit_bigstring_to_bytes src.buffer (src.off+srcoff) b 0 len;
     (* The following call is safe, since b is not visible elsewhere. *)
     Bytes.unsafe_to_string b
 
+let copy = copy_to_string "copy"
+
 let blit src srcoff dst dstoff len =
   if len < 0 || srcoff < 0 || src.len - srcoff < len then
     err_blit_src src dst srcoff len
@@ -398,9 +400,7 @@ let fillv ~src ~dst =
 
 let to_string ?(off=0) ?len:sz t =
   let len = match sz with None -> length t - off | Some l -> l in
-  (* The following call is safe, since this is the only reference to the
-     freshly-created value built by [to_bytes t]. *)
-  copy t off len
+  copy_to_string "to_string" t off len
 
 let to_hex_string ?(off=0) ?len:sz t : string =
   let[@inline] nibble_to_char (i:int) : char =

lib/cstruct.mli

@@ -292,8 +292,10 @@ val shift: t -> int -> t
     @raise Invalid_argument if the offset exceeds cstruct length. *)
 
 val copy: t -> int -> int -> string
+[@@ocaml.alert deprecated "this is just like [to_string] without defaults, were you looking for [sub_copy]?"]
 (** [copy cstr off len] is the string representation of the segment of
-    [t] starting at [off] of size [len].
+    [t] starting at [off] of size [len]. It is equivalent to
+    [Cstruct.to_string cstr ~off ~len].
     @raise Invalid_argument if [off] and [len] do not designate a
     valid segment of [t]. *)
 

lib/cstruct_cap.mli

@@ -177,6 +177,10 @@ val split : ?start:int -> 'a t -> int -> 'a t * 'a t
     @raise Invalid_argument if [start] exceeds the length of [t],
     or if there is a bounds violation of [t] via [len + start]. *)
 
+val copy : 'a t -> int -> int -> string
+[@@ocaml.alert deprecated "this is just like [to_string] without defaults, were you looking for [sub_copy]?"]
+(** [copy cstr off len] is the same as [Cstruct.to_string cstr ~off ~len]. *)
+
 (** {2 Construction from existing t} *)
 
 val append : 'a rd t -> 'b rd t -> rdwr t

ppx/ppx_cstruct.ml

@@ -298,7 +298,7 @@ let op_expr loc s = function
   | Op_set f -> set_expr loc s f
   | Op_copy f ->
     let len = width_of_field f in
-    [%expr fun src -> Cstruct.copy src [%e Ast.eint ~loc f.off] [%e Ast.eint ~loc len] ]
+    [%expr fun src -> Cstruct.to_string src ~off:[%e Ast.eint ~loc f.off] ~len:[%e Ast.eint ~loc len] ]
   | Op_blit f ->
     let len = width_of_field f in
     [%expr fun src srcoff dst ->