From 2a66e9d057bee3f0afddcdcfe3be3996b8adf65c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Vouillon?= <jvouillon@besport.com>
Date: Tue, 27 Sep 2022 12:20:36 +0200
Subject: [PATCH] Adapt to OCaml changes

---
 Makefile                  |  2 +-
 README.txt                |  5 ++--
 database/column.ml        | 25 ++++++++--------
 database/rtree.ml         |  2 +-
 database/table.ml         |  6 ++--
 generic/bitvect.ml        |  8 +++---
 generic/bytearray.ml      | 20 +++++--------
 generic/bytearray.mli     |  2 --
 generic/bytearray_stubs.c |  4 +--
 generic/mapped_file.ml    | 15 ++++++----
 generic/protobuf.ml       |  6 ++--
 generic/task.ml           | 18 ++++++------
 generic/util.ml           | 60 +++++++++++++++++++--------------------
 generic/util.mli          |  2 +-
 osm/coastline.ml          | 11 ++++---
 osm/highway.ml            |  8 +++---
 osm/lib/osm_display.ml    | 21 +++++++-------
 osm/parser.ml             | 16 +++++------
 osm/surfaces.ml           | 14 ++++-----
 19 files changed, 122 insertions(+), 123 deletions(-)

diff --git a/Makefile b/Makefile
index d90da2d..6103ca2 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ OCAMLLEX=ocamllex
 OCAMLYACC=ocamlyacc -v
 OCAMLDEP=ocamldep
 
-OPTCOMPFLAGS =-package zip,bigarray,unix,cairo2.lablgtk2 -inline 3 -g \
+OPTCOMPFLAGS =-package zip,bigarray,unix,cairo2-gtk -inline 3 -g \
   $(DIRS)
 COMPFLAGS = $(DIRS)
 DEPFLAGS= $(DIRS)
diff --git a/README.txt b/README.txt
index 13907d5..3a1107a 100644
--- a/README.txt
+++ b/README.txt
@@ -5,7 +5,7 @@ This software only works on 64-bit machines.
 The following external libraries are needed: camlzip, cairo, lablgtk.
 They can be install through opam:
 
-   opam install camlzip cairo2 lablgtk
+   opam install camlzip cairo2-gtk
 
 To compile, just type 'make'.
 
@@ -102,9 +102,8 @@ to display the map:
 
 Optionally, you can include the coastline data:
 - download coastlines-split-4326.zip from
-  http://openstreetmapdata.com/data/coastlines
+  https://osmdata.openstreetmap.de/data/coastlines.html
   (shapefile format, containing linestrings in WGS84 projection)
-- unzip the file
 - build the coastline R-trees:
     ./coastline /path/to/coastlines-split-4326.zip
 
diff --git a/database/column.ml b/database/column.ml
index e9eafd6..c6d8bbc 100644
--- a/database/column.ml
+++ b/database/column.ml
@@ -342,7 +342,7 @@ module Output_stream_write = struct
   type output_stream =
     { fd : Unix.file_descr;
       mutable pos : int;
-      write_buffer : string;
+      write_buffer : bytes;
       mutable buf_pos : int;
       buffer : int array;
       mutable i : int;
@@ -357,7 +357,7 @@ module Output_stream_write = struct
       Unix.openfile nm [Unix.O_RDWR; Unix.O_CREAT; Unix.O_TRUNC] 0o666 in
     if temp <> None then Unix.unlink nm;
     ignore (Unix.lseek fd 24 Unix.SEEK_SET);
-    { fd = fd; write_buffer = String.create (write_size + max_overhead);
+    { fd = fd; write_buffer = Bytes.create (write_size + max_overhead);
       buffer = Array.make block_size 0; table = [||];
       pos = 24; buf_pos = 0; i = 0; n = 0 }
 
@@ -372,11 +372,12 @@ module Output_stream_write = struct
     end;
     s.table.(s.n - 1) <- s.pos
 
-  external encode_chunk : string -> int -> int array -> int -> int -> int
+  external encode_chunk : bytes -> int -> int array -> int -> int -> int
     = "encode_chunk_to_string_ml"
 
   let write_int_2 a p v =
-    a.[p] <- Char.chr (v land 0xff); a.[p + 1] <- Char.chr ((v lsr 8) land 0xff)
+    Bytes.set a p (Char.chr (v land 0xff));
+    Bytes.set a (p + 1) (Char.chr ((v lsr 8) land 0xff))
 
   let write_int_8 a p v =
     let v = ref v in
@@ -394,7 +395,7 @@ module Output_stream_write = struct
     let len = min write_size s.buf_pos in
     really_write s.fd s.write_buffer 0 len;
     if len < s.buf_pos then
-      String.blit s.write_buffer len s.write_buffer 0 (s.buf_pos - len);
+      Bytes.blit s.write_buffer len s.write_buffer 0 (s.buf_pos - len);
     s.buf_pos <- s.buf_pos - len
 
   let flush_buffer s =
@@ -433,19 +434,19 @@ module Output_stream_write = struct
     if i > 0 then flush_buffer s;
     write_buffer s;
     assert (s.buf_pos = 0);
-    let a = String.create (8 * s.n) in
+    let a = Bytes.create (8 * s.n) in
     for j = 0 to s.n - 1 do
       write_int_8 a (8 * j) s.table.(j)
     done;
     assert (Unix.lseek s.fd 0 Unix.SEEK_CUR = s.pos);
-    really_write s.fd a 0 (String.length a);
+    really_write s.fd a 0 (Bytes.length a);
     let len = (s.n - 1) * block_size + (if i = 0 then block_size else i) in
 
-    let a = magic ^ String.create 16 in
+    let a = Bytes.cat (Bytes.of_string magic) (Bytes.create 16) in
     write_int_8 a 8 len;
     write_int_8 a 16 s.pos;
     ignore (Unix.lseek s.fd 0 Unix.SEEK_SET);
-    really_write s.fd a 0 (String.length a)
+    really_write s.fd a 0 (Bytes.length a)
 
   let close_out s =
     finish_output s;
@@ -648,8 +649,8 @@ let with_spec_2 f nm1 nm2 =
 (****)
 
 let is_column nm =
-  let ch = Pervasives.open_in (file_in_database nm) in
-  let s = String.make 8 ' ' in
+  let ch = Stdlib.open_in (file_in_database nm) in
+  let s = Bytes.make 8 ' ' in
   ignore (input ch s 0 8);
   close_in ch;
-  s = magic
+  Bytes.unsafe_to_string s = magic
diff --git a/database/rtree.ml b/database/rtree.ml
index 0e7c050..d5c5cf0 100644
--- a/database/rtree.ml
+++ b/database/rtree.ml
@@ -63,7 +63,7 @@ end
 
 type level =
   { mutable level_bbox : Bbox.t;
-    buffer : string;
+    buffer : bytes;
     file : (int32, Bigarray.int32_elt) Mapped_file.output_stream;
     mutable idx : int }
 
diff --git a/database/table.ml b/database/table.ml
index 442bbb4..a9ceaea 100644
--- a/database/table.ml
+++ b/database/table.ml
@@ -32,7 +32,8 @@ let make ?len nm kind =
   let ch = Unix.openfile nm flags 0o600 in
   let l = match len with None -> map_incr | Some l -> l in
   { ch = ch;
-    ar = Bigarray.Array1.map_file ch kind Bigarray.c_layout true l }
+    ar = Bigarray.array1_of_genarray
+           (Unix.map_file ch kind Bigarray.c_layout true [|l|]) }
 
 let extend a l =
   let l' = ref (Bigarray.Array1.dim a.ar) in
@@ -41,7 +42,8 @@ Format.printf "RESIZE@.";
     while !l' < l do l' := !l' + map_incr done;
     let kind = Bigarray.Array1.kind a.ar in
     let layout = Bigarray.Array1.layout a.ar in
-    a.ar <- Bigarray.Array1.map_file a.ch kind layout true !l'
+    a.ar <- Bigarray.array1_of_genarray
+              (Unix.map_file a.ch kind layout true [|!l'|])
   end
 
 (****)
diff --git a/generic/bitvect.ml b/generic/bitvect.ml
index 89363a1..9d534e6 100644
--- a/generic/bitvect.ml
+++ b/generic/bitvect.ml
@@ -16,14 +16,14 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  *)
 
-type t = string
+type t = bytes
 
-let make n = String.make ((n + 7) lsr 3) '\000'
+let make n = Bytes.make ((n + 7) lsr 3) '\000'
 
 let set v i =
   let j = i lsr 3 in
-  v.[j] <- Char.chr (Char.code v.[j] lor (1 lsl (i land 7)))
+  Bytes.set v j (Char.chr (Char.code (Bytes.get v j) lor (1 lsl (i land 7))))
 
 let test v i =
   let j = i lsr 3 in
-  Char.code v.[j] land (1 lsl (i land 7)) <> 0
+  Char.code (Bytes.get v j) land (1 lsl (i land 7)) <> 0
diff --git a/generic/bytearray.ml b/generic/bytearray.ml
index e0b3b1f..4454332 100644
--- a/generic/bytearray.ml
+++ b/generic/bytearray.ml
@@ -37,17 +37,17 @@ let unsafe_blit_to_string a i s j l =
 *)
 
 external unsafe_blit_from_string : string -> int -> t -> int -> int -> unit
-  = "ml_blit_string_to_bigarray" "noalloc"
+  = "ml_blit_string_to_bigarray" [@@noalloc]
 
-external unsafe_blit_to_string : t -> int -> string -> int -> int -> unit
-  = "ml_blit_bigarray_to_string" "noalloc"
+external unsafe_blit_to_string : t -> int -> bytes -> int -> int -> unit
+  = "ml_blit_bigarray_to_string" [@@noalloc]
 
 let to_string a =
   let l = length a in
   if l > Sys.max_string_length then invalid_arg "Bytearray.to_string" else
-  let s = String.create l in
+  let s = Bytes.create l in
   unsafe_blit_to_string a 0 s 0 l;
-  s
+  Bytes.unsafe_to_string s
 
 let of_string s =
   let l = String.length s in
@@ -61,9 +61,9 @@ let sub a ofs len =
   then
     invalid_arg "Bytearray.sub"
   else begin
-    let s = String.create len in
+    let s = Bytes.create len in
     unsafe_blit_to_string a ofs s 0 len;
-    s
+    Bytes.unsafe_to_string s
   end
 
 let rec prefix_rec a i a' i' l =
@@ -82,12 +82,6 @@ let blit_from_string s i a j l =
   then invalid_arg "Bytearray.blit_from_string"
   else unsafe_blit_from_string s i a j l
 
-let blit_to_string a i s j l =
-  if l < 0 || i < 0 || i > length a - l
-           || j < 0 || j > String.length s - l
-  then invalid_arg "Bytearray.blit_to_string"
-  else unsafe_blit_to_string a i s j l
-
 external marshal : 'a -> Marshal.extern_flags list -> t
   = "ml_marshal_to_bigarray"
 
diff --git a/generic/bytearray.mli b/generic/bytearray.mli
index 796f6fa..fa697f9 100644
--- a/generic/bytearray.mli
+++ b/generic/bytearray.mli
@@ -31,8 +31,6 @@ val sub : t -> int -> int -> string
 
 val blit_from_string : string -> int -> t -> int -> int -> unit
 
-val blit_to_string : t -> int -> string -> int -> int -> unit
-
 val prefix : t -> t -> int -> bool
 
 val marshal : 'a -> Marshal.extern_flags list -> t
diff --git a/generic/bytearray_stubs.c b/generic/bytearray_stubs.c
index e4abf8b..6d55c1b 100644
--- a/generic/bytearray_stubs.c
+++ b/generic/bytearray_stubs.c
@@ -51,7 +51,7 @@ CAMLprim value ml_unmarshal_from_bigarray(value b, value ofs)
 CAMLprim value ml_blit_string_to_bigarray
 (value s, value i, value a, value j, value l)
 {
-  char *src = String_val(s) + Int_val(i);
+  const char *src = String_val(s) + Int_val(i);
   char *dest = Array_data(Bigarray_val(a), j);
   memcpy(dest, src, Long_val(l));
   return Val_unit;
@@ -61,7 +61,7 @@ CAMLprim value ml_blit_bigarray_to_string
 (value a, value i, value s, value j, value l)
 {
   char *src = Array_data(Bigarray_val(a), i);
-  char *dest = String_val(s) + Long_val(j);
+  char *dest = Bytes_val(s) + Long_val(j);
   memcpy(dest, src, Long_val(l));
   return Val_unit;
 }
diff --git a/generic/mapped_file.ml b/generic/mapped_file.ml
index 2451fe9..ef0446f 100644
--- a/generic/mapped_file.ml
+++ b/generic/mapped_file.ml
@@ -88,7 +88,8 @@ let open_out nm ?temp map_incr (kind, element_size) =
   let ch = Unix.openfile nm flags 0o600 in
   if temp then Unix.unlink nm;
   { ch = ch; map_incr = map_incr; len = 0;
-    ar = Bigarray.Array1.map_file ch kind Bigarray.c_layout true map_incr;
+    ar = Bigarray.array1_of_genarray
+           (Unix.map_file ch kind Bigarray.c_layout true [|map_incr|]);
     element_size = element_size }
 
 let resize s l =
@@ -97,7 +98,8 @@ let resize s l =
   if !l' < l then begin
     while !l' < l do l' := !l' + s.map_incr done;
     let kind = Bigarray.Array1.kind s.ar in
-    s.ar <- Bigarray.Array1.map_file s.ch kind Bigarray.c_layout true !l'
+    s.ar <- Bigarray.array1_of_genarray
+              (Unix.map_file s.ch kind Bigarray.c_layout true [|!l'|])
   end
 
 let output_array s = s.ar
@@ -111,12 +113,14 @@ type ('a, 'b) t = ('a, 'b, Bigarray.c_layout) Bigarray.Array1.t
 let open_in nm kind =
   let flags = [Unix.O_RDWR] in
   let ch = Unix.openfile nm flags 0o600 in
-  let a = Bigarray.Array1.map_file ch kind Bigarray.c_layout true (-1) in
+  let a = Bigarray.array1_of_genarray
+             (Unix.map_file ch kind Bigarray.c_layout true [|-1|]) in
   Unix.close ch;
   a
 
 let open_in_fd ch kind =
-  let a = Bigarray.Array1.map_file ch kind Bigarray.c_layout true (-1) in
+  let a = Bigarray.array1_of_genarray
+             (Unix.map_file ch kind Bigarray.c_layout true [|-1|]) in
   Unix.close ch;
   a
 
@@ -125,6 +129,7 @@ let array a = a
 let freeze s =
   Unix.ftruncate s.ch s.len;
   let kind = Bigarray.Array1.kind s.ar in
-  let a = Bigarray.Array1.map_file s.ch kind Bigarray.c_layout true (-1) in
+  let a = Bigarray.array1_of_genarray
+             (Unix.map_file s.ch kind Bigarray.c_layout true [|-1|]) in
   Unix.close s.ch;
   a
diff --git a/generic/protobuf.ml b/generic/protobuf.ml
index 37977b8..e72b389 100644
--- a/generic/protobuf.ml
+++ b/generic/protobuf.ml
@@ -50,12 +50,10 @@ let buffer_copy b = {s = b.s; i = b.i; l = b.l}
 let empty_buffer = {s =""; i = 0; l = 0}
 
 let input_string ch l =
-  let s = String.create l in
-  really_input ch s 0 l;
-  s
+  really_input_string ch l
 
 let buffer_from_channel ch l =
-  buffer_from_substring (input_string ch l) 0 l
+  buffer_from_substring (really_input_string ch l) 0 l
 
 let chunk buf l =
   let i = buf.i in
diff --git a/generic/task.ml b/generic/task.ml
index 6e2c4d7..9fe195e 100644
--- a/generic/task.ml
+++ b/generic/task.ml
@@ -62,13 +62,13 @@ let functions = Hashtbl.create 17
 
 let send pipe i l =
   let s = Printf.sprintf "%d %d\n" i l in
-  ignore (Unix.write pipe s 0 (String.length s))
+  ignore (Unix.write_substring pipe s 0 (String.length s))
 
 let receive pipe =
-  let s = String.create 50 in
-  let len = Unix.read pipe s 0 (String.length s) in
+  let s = Bytes.create 50 in
+  let len = Unix.read pipe s 0 (Bytes.length s) in
   if len = 0 then exit 1;
-  Scanf.sscanf s "%d %d" (fun i l -> (i, l))
+  Scanf.sscanf (Bytes.unsafe_to_string s) "%d %d" (fun i l -> (i, l))
 
 let read mem l =
   let t = Utimer.start () in
@@ -114,15 +114,17 @@ let spawn f =
     let fd = Unix.openfile "/dev/zero" [Unix.O_RDWR] 0 in
     let mem =
       try
-        Bigarray.Array1.map_file
-          fd Bigarray.char Bigarray.c_layout true mem_size
+        Bigarray.array1_of_genarray
+             (Unix.map_file
+                fd Bigarray.char Bigarray.c_layout true [|mem_size|])
       with Sys_error _ ->
         (* Mac OS X does not support this, so we use a temp file instead. *)
         let (nm, ch) = Filename.open_temp_file "mmap" "" in
         Sys.remove nm;
         let mem =
-          Bigarray.Array1.map_file (Unix.descr_of_out_channel ch)
-            Bigarray.char Bigarray.c_layout true mem_size
+          Bigarray.array1_of_genarray
+             (Unix.map_file (Unix.descr_of_out_channel ch)
+                Bigarray.char Bigarray.c_layout true [|mem_size|])
         in
         close_out ch;
         mem
diff --git a/generic/util.ml b/generic/util.ml
index 30ef289..179f043 100644
--- a/generic/util.ml
+++ b/generic/util.ml
@@ -43,12 +43,12 @@ let set_msg s =
 (****)
 
 let progress_bar f =
-  let s = "[                                       ]" in
+  let s = Bytes.of_string "[                                       ]" in
   let p = truncate (f *. 38.99) + 1 in
-  for i = 1 to p - 1 do s.[i] <- '=' done;
-  s.[p] <- '>';
-  for i = p + 1 to 39 do s.[i] <- ' ' done;
-  s
+  for i = 1 to p - 1 do Bytes.set s i '=' done;
+  Bytes.set s p '>';
+  for i = p + 1 to 39 do Bytes.set s i ' ' done;
+  Bytes.to_string s
 
 (****)
 
@@ -155,9 +155,9 @@ let rec make_directories f =
 
 (****)
 
-let string_extend s n c =
-  let s' = String.make n c in
-  String.blit s 0 s' 0 (String.length s);
+let bytes_extend s n c =
+  let s' = Bytes.make n c in
+  Bytes.blit s 0 s' 0 (Bytes.length s);
   s'
 
 let array_extend a n v =
@@ -168,44 +168,44 @@ let array_extend a n v =
 (****)
 
 module BitVect = struct
-  type t = string
-  let make n v = String.make n (if v then 'T' else 'F')
-  let test vect x = vect.[x] <> 'F'
-  let set vect x = vect.[x] <- 'T'
-  let clear vect x = vect.[x] <- 'F'
-  let copy = String.copy
-  let extend vect n v = string_extend vect n (if v then 'T' else 'F')
-  let sub = String.sub
+  type t = bytes
+  let make n v = Bytes.make n (if v then 'T' else 'F')
+  let test vect x = Bytes.get vect x <> 'F'
+  let set vect x = Bytes.set vect x 'T'
+  let clear vect x = Bytes.set vect x 'F'
+  let copy = Bytes.copy
+  let extend vect n v = bytes_extend vect n (if v then 'T' else 'F')
+  let sub = Bytes.sub
   let implies vect1 vect2 =
-    let l = String.length vect1 in
-    assert (String.length vect2 = l);
+    let l = Bytes.length vect1 in
+    assert (Bytes.length vect2 = l);
     let rec implies_rec vect1 vect2 i l =
       i = l ||
-      ((vect1.[i] <> 'T' || vect2.[i] = 'T') &&
+      ((Bytes.get vect1 i <> 'T' || Bytes.get vect2 i = 'T') &&
        implies_rec vect1 vect2 (i + 1) l)
     in
     implies_rec vect1 vect2 0 l
   let lnot vect =
-    let l = String.length vect in
-    let vect' = String.make l 'F' in
+    let l = Bytes.length vect in
+    let vect' = Bytes.make l 'F' in
     for i = 0 to l - 1 do
-      vect'.[i] <- if vect.[i] = 'F' then 'T' else 'F'
+      Bytes.set vect' i (if Bytes.get vect i = 'F' then 'T' else 'F')
     done;
     vect'
   let (land) vect1 vect2 =
-    let l = String.length vect1 in
-    assert (String.length vect2 = l);
-    let vect = String.make l 'F' in
+    let l = Bytes.length vect1 in
+    assert (Bytes.length vect2 = l);
+    let vect = Bytes.make l 'F' in
     for i = 0 to l - 1 do
-      vect.[i] <- if vect1.[i] = 'F' || vect2.[i] = 'F' then 'F' else 'T'
+      Bytes.set vect i (if Bytes.get vect1 i = 'F' || Bytes.get vect2 i = 'F' then 'F' else 'T')
     done;
     vect
   let (lor) vect1 vect2 =
-    let l = String.length vect1 in
-    assert (String.length vect2 = l);
-    let vect = String.make l 'F' in
+    let l = Bytes.length vect1 in
+    assert (Bytes.length vect2 = l);
+    let vect = Bytes.make l 'F' in
     for i = 0 to l - 1 do
-      vect.[i] <- if vect1.[i] = 'F' && vect2.[i] = 'F' then 'F' else 'T'
+      Bytes.set vect i (if Bytes.get vect1 i = 'F' && Bytes.get vect2 i = 'F' then 'F' else 'T')
     done;
     vect
 end
diff --git a/generic/util.mli b/generic/util.mli
index 55abd1d..88ef7fe 100644
--- a/generic/util.mli
+++ b/generic/util.mli
@@ -60,7 +60,7 @@ end
 module StringTbl : Hashtbl.S with type key = string
 
 val array_extend : 'a array -> int -> 'a -> 'a array
-val string_extend : string -> int -> char -> string
+val bytes_extend : bytes -> int -> char -> bytes
 
 val print_list :
   (Format.formatter -> 'a -> unit) -> string ->
diff --git a/osm/coastline.ml b/osm/coastline.ml
index 6cad462..1207088 100644
--- a/osm/coastline.ml
+++ b/osm/coastline.ml
@@ -178,13 +178,13 @@ let load () =
   done;
 
 (*
-  let a = read_float ch in 
+  let a = read_float ch in
   Format.eprintf "%f@." a;
-  let a = read_float ch in 
+  let a = read_float ch in
   Format.eprintf "%f@." a;
-  let a = read_float ch in 
+  let a = read_float ch in
   Format.eprintf "%f@." a;
-  let a = read_float ch in 
+  let a = read_float ch in
   Format.eprintf "%f@." a;
 *)
 
@@ -399,7 +399,7 @@ let open_rtree name ratio =
   let ch = open_out nm in
   let lengths = Array.make (leaf_size / 4) 0 in
   let n = ref 0 in
-  let buf = String.make (2 * leaf_size) '\000' in
+  let buf = Bytes.make (2 * leaf_size) '\000' in
   let pos = ref 0 in
   let bbox = ref Bbox.empty in
   let last_lat = ref 0 in
@@ -534,4 +534,3 @@ let _ =
   build_rtree_simpl 6. "6";
   build_rtree_simpl 4. "4";
   build_rtree_simpl 2. "2"
-
diff --git a/osm/highway.ml b/osm/highway.ml
index 7223beb..e098f5a 100644
--- a/osm/highway.ml
+++ b/osm/highway.ml
@@ -340,7 +340,7 @@ type state =
 
 type level =
   { mutable level_bbox : bbox;
-    buffer : string;
+    buffer : bytes;
     file : (int32, Bigarray.int32_elt) Mapped_file.output_stream;
     mutable idx : int }
 
@@ -384,8 +384,8 @@ let _ =
   let latitude = Column.open_in (Column.named "highway" "sorted_node/lat") in
   let longitude = Column.open_in (Column.named "highway" "sorted_node/lon") in
 
-  let node_buf = String.create (16 * 1024) in
-  let edge_buf = String.create (16 * 1024) in
+  let node_buf = Bytes.create (16 * 1024) in
+  let edge_buf = Bytes.create (16 * 1024) in
 
   Util.make_directories (Column.file_in_database "highway/r_tree/0");
   let leaves = open_out (Column.file_in_database "highway/r_tree/0") in
@@ -404,7 +404,7 @@ let _ =
         Util.make_directories file;
         let st =
           { level_bbox = new_bbox ();
-            buffer = String.create (16 * 1024);
+            buffer = Bytes.create (16 * 1024);
             file = Mapped_file.open_out file node_size Mapped_file.int32;
             idx = 0 }
         in
diff --git a/osm/lib/osm_display.ml b/osm/lib/osm_display.ml
index 1da65fc..d873790 100644
--- a/osm/lib/osm_display.ml
+++ b/osm/lib/osm_display.ml
@@ -71,7 +71,7 @@ let sint_of_int i = let i' = i lsr 1 in if i land 1 = 1 then (-i' - 1) else i'
 
 let rec read_varint_rec a p v offs =
   let i = !p in
-  let c = Char.code a.[i] in
+  let c = Char.code (Bytes.get a i) in
   incr p;
   if c >= 0x80 then
     read_varint_rec a p (v lor ((c land 0x7f) lsl offs)) (offs + 7)
@@ -82,7 +82,8 @@ let read_varint a p = read_varint_rec a p 0 0
 
 let read_signed_varint a p = sint_of_int (read_varint a p)
 
-let read_int_2 s pos = Char.code s.[pos] lor (Char.code s.[pos + 1] lsl 8)
+let read_int_2 s pos =
+  Char.code (Bytes.get s pos) lor (Char.code (Bytes.get s (pos + 1)) lsl 8)
 
 (****)
 
@@ -450,8 +451,8 @@ let decode_leaf ratio leaves i =
     node := n1;
     let n2 = !node + read_signed_varint buf pos in
     node := n2;
-    let cat = Char.code buf.[!pos] in
-    let layer = Char.code buf.[!pos + 1] in
+    let cat = Char.code (Bytes.get buf !pos) in
+    let layer = Char.code (Bytes.get buf (!pos + 1)) in
     pos := !pos + 2;
     edges.(!i) <- (n1, n2, cat, layer, nodes);
     incr i
@@ -562,15 +563,15 @@ let surface_leaf_size = 2048
 let surface_leaf_read = ref 0
 
 let decode_surfaces ratio leaves i =
-  let buf = String.create surface_leaf_size in
+  let buf = Bytes.create surface_leaf_size in
   seek_in leaves (i * surface_leaf_size);
   really_input leaves buf 0 surface_leaf_size;
   let len = read_int_2 buf 0 in
   surface_leaf_read := !surface_leaf_read + len;
   let buf =
     if len > 1 then begin
-      let buf' = String.create (surface_leaf_size * len) in
-      String.blit buf 0 buf' 0 surface_leaf_size;
+      let buf' = Bytes.create (surface_leaf_size * len) in
+      Bytes.blit buf 0 buf' 0 surface_leaf_size;
       really_input leaves buf' surface_leaf_size
         ((len - 1) * surface_leaf_size);
       buf'
@@ -587,8 +588,8 @@ let decode_surfaces ratio leaves i =
   let lst = ref [] in
   for i = 0 to n - 1 do
     let l = read_int_2 buf (4 + 4 * i) in
-    let cat = Char.code buf.[4 + 4 * i + 2] in
-    let lay = Char.code buf.[4 + 4 * i + 3] - 128 in
+    let cat = Char.code (Bytes.get buf (4 + 4 * i + 2)) in
+    let lay = Char.code (Bytes.get buf (4 + 4 * i + 3)) - 128 in
     if cat <> 0 then begin
       if !ways <> [] then lst := (!category, !layer, List.rev !ways) :: !lst;
       category := cat;
@@ -686,7 +687,7 @@ let grow_surface pm window width height =
     let p =
       Cairo.Surface.create_similar
         (Cairo.get_target (Cairo_gtk.create window#misc#window))
-        Cairo.COLOR_ALPHA ~width ~height
+        Cairo.COLOR_ALPHA ~w:width ~h:height
     in
     let r = pm.valid_rect in
     begin match old_p with
diff --git a/osm/parser.ml b/osm/parser.ml
index a96f0f2..d3a882a 100644
--- a/osm/parser.ml
+++ b/osm/parser.ml
@@ -43,9 +43,9 @@ let b4 ch =
 
 let uncompress sz inbuf =
   let zs = Zlib.inflate_init true in
-  let outbuf = String.create sz in
+  let outbuf = Bytes.create sz in
   let (finished, used_in, used_out) =
-    Zlib.inflate zs inbuf 0 (String.length inbuf) outbuf 0 sz Zlib.Z_SYNC_FLUSH
+    Zlib.inflate_string zs inbuf 0 (String.length inbuf) outbuf 0 sz Zlib.Z_SYNC_FLUSH
   in
   assert finished;
   assert (used_out = sz);
@@ -81,7 +81,7 @@ let parse_blob ch =
 
   let data = uncompress raw_size zlib_data in
 
-  (typ, data)
+  (typ, Bytes.unsafe_to_string data)
 
 (****)
 
@@ -429,16 +429,16 @@ let parse_primitive_block state data =
 (****)
 
 let perc_str f =
-  let s = "[                                       ]" in
+  let s = Bytes.of_string "[                                       ]" in
   let p = truncate (f *. 38.99) + 1 in
-  for i = 1 to p - 1 do s.[i] <- '=' done;
+  for i = 1 to p - 1 do Bytes.set s i '=' done;
   s.[p] <- '>';
-  for i = p + 1 to 39 do s.[i] <- ' ' done;
-  s
+  for i = p + 1 to 39 do Bytes.set s i ' ' done;
+  Bytes.to_string s
 
 let parse_primitive_block = Task.funct parse_primitive_block
 let close_state = Task.funct (fun state () -> close_state state)
-let fut = ref None 
+let fut = ref None
 let synchronize f =
   begin match !fut with
     Some f -> Task.wait f
diff --git a/osm/surfaces.ml b/osm/surfaces.ml
index 2e84616..9262beb 100644
--- a/osm/surfaces.ml
+++ b/osm/surfaces.ml
@@ -83,14 +83,14 @@ let resize_array size a =
     a := a'
   end
 
-let resize_string size s =
-  let l = String.length !s in
+let resize_bytes size s =
+  let l = Bytes.length !s in
   assert (l > 0);
   if l < size then begin
     let l' = ref l in
     while !l' < size do l' := 2 * !l' done;
-    let s' = String.make !l' !s.[0] in
-    String.blit !s 0 s' 0 l;
+    let s' = Bytes.make !l' (Bytes.get !s 0) in
+    Bytes.blit !s 0 s' 0 l;
     s := s'
   end
 
@@ -480,7 +480,7 @@ let open_rtree name ratio =
   let categories = ref (Array.make (leaf_size / 8) 0) in
   let layers = ref (Array.make (leaf_size / 8) 0) in
   let n = ref 0 in
-  let buf = ref (String.make (256 + leaf_size) '\000') in
+  let buf = ref (Bytes.make (256 + leaf_size) '\000') in
   let pos = ref 0 in
   let bbox = ref Bbox.empty in
   let last_lat = ref 0 in
@@ -501,7 +501,7 @@ Format.eprintf "%d %d %d@." len !n !pos;
     for i = 1 to len - 1 do
       Rtree.append st Bbox.empty
     done;
-    resize_string (len * leaf_size - !n * 4 - 4) buf;
+    resize_bytes (len * leaf_size - !n * 4 - 4) buf;
     output ch !buf 0 (len * leaf_size - !n * 4 - 4);
     n := 0;
     pos := 0;
@@ -519,7 +519,7 @@ let ch = open_out "/tmp/c" in
 	(fun pos (lat, lon) ->
 	   let pos = ref pos in
 	   for i = 0 to Array.length lat - 2 do
-             resize_string (!pos + 20) buf;
+             resize_bytes (!pos + 20) buf;
 	     pos := write_signed_varint !buf !pos (lat.(i) - !last_lat);
 (*
 Printf.fprintf ch "%d\n" (lat.(i) - !last_lat);