xapi-stdext-std: change String.replace to replace characters

The few users that needed to replace strings, have been replaced with Astring's
cuts, as most of them were already segmenting strings, or they are run in very
specific, infrequent codepaths for efficiency to not matter.

Others have been replaced by Astring's filter as they were removing characters,
and the rest have been converted to the new String.replace.

map_unlikely can be removed from the interface and only have String.replaced
and String.replace

Signed-off-by: Pau Ruiz Safont <pau.ruizsafont@cloud.com>
Signed-off-by: Pau Ruiz Safont <pau.safont@vates.tech>

Author: psafont

ocaml/idl/ocaml_backend/gen_rbac.ml

@@ -85,7 +85,7 @@ let permission_description = "A basic permission"
 let permission_name wire_name =
   let s1 = replace_char (Printf.sprintf "permission_%s" wire_name) '.' '_' in
   let s2 = replace_char s1 '/' '_' in
-  let s3 = Xapi_stdext_std.Xstringext.String.replace "*" "WILDCHAR" s2 in
+  let s3 = Xapi_stdext_std.Xstringext.String.replace '*' ~by:"WILDCHAR" s2 in
   replace_char s3 ':' '_'
 
 let permission_index = ref 0

ocaml/libs/xapi-stdext/lib/xapi-stdext-std/xstringext.ml

@@ -32,46 +32,6 @@ module String = struct
     else
       s
 
-  (** find all occurences of needle in haystack and return all their respective index *)
-  let find_all needle haystack =
-    let m = String.length needle and n = String.length haystack in
-    if m > n then
-      []
-    else
-      let i = ref 0 and found = ref [] in
-      while !i < n - m + 1 do
-        if String.sub haystack !i m = needle then (
-          found := !i :: !found ;
-          i := !i + m
-        ) else
-          incr i
-      done ;
-      List.rev !found
-
-  (* replace all @f substring in @s by @t *)
-  let replace f t s =
-    let indexes = find_all f s in
-    let n = List.length indexes in
-    if n > 0 then (
-      let len_f = String.length f and len_t = String.length t in
-      let new_len = String.length s + (n * len_t) - (n * len_f) in
-      let new_b = Bytes.make new_len '\000' in
-      let orig_offset = ref 0 and dest_offset = ref 0 in
-      List.iter
-        (fun h ->
-          let len = h - !orig_offset in
-          Bytes.blit_string s !orig_offset new_b !dest_offset len ;
-          Bytes.blit_string t 0 new_b (!dest_offset + len) len_t ;
-          orig_offset := !orig_offset + len + len_f ;
-          dest_offset := !dest_offset + len + len_t
-        )
-        indexes ;
-      Bytes.blit_string s !orig_offset new_b !dest_offset
-        (String.length s - !orig_offset) ;
-      Bytes.unsafe_to_string new_b
-    ) else
-      s
-
   let map_unlikely s f =
     let changed = ref false in
     let m = ref 0 in
@@ -92,5 +52,15 @@ module String = struct
     ) else
       s
 
+  let replace char ~by s =
+    let replaceable = Stdlib.Char.equal char in
+    let get_replacement c =
+      if replaceable c then
+        Some by
+      else
+        None
+    in
+    map_unlikely s get_replacement
+
   let replaced ~replace s = map_unlikely s replace
 end

ocaml/libs/xapi-stdext/lib/xapi-stdext-std/xstringext.mli

@@ -17,18 +17,16 @@ module String : sig
       and when it returns [Some rep] the character is replaced with [rep] in
       the resulting string *)
 
+  val replace : char -> by:string -> string -> string
+  (** [replace ch ~by s] replaces all the occurrences of [ch] in [s] by [~by]
+    *)
+
   val split : limit:int -> char -> string -> string list
   (** split a string on a single char *)
 
   val rtrim : string -> string
   (** FIXME document me|remove me if similar to strip *)
 
-  val replace : string -> string -> string -> string
-  (** replace all [f] substring in [s] by [t] *)
-
-  val map_unlikely : string -> (char -> string option) -> string
-  (** map a string trying to fill the buffer by chunk *)
-
   val sub_to_end : string -> int -> string
   (** a substring from the specified position to the end of the string *)
 end

ocaml/libs/xapi-stdext/lib/xapi-stdext-std/xstringext_test.ml

@@ -75,23 +75,23 @@ let test_rtrim =
 let test_replace =
   let spec =
     [
-      (("*", "WILDCHAR", ""), "")
-    ; (("*", "", "*"), "")
-    ; (("*", "WILDCHAR", "*"), "WILDCHAR")
-    ; (("*", "WILDCHAR", "**"), "WILDCHARWILDCHAR")
-    ; (("*", "WILDCHAR", "***"), "WILDCHARWILDCHARWILDCHAR")
-    ; (({|"|}, "", ""), "")
-    ; (({|"|}, "", "a"), "a")
-    ; (({|"|}, "", {|"a"|}), "a")
-    ; (({|"|}, "", {|a"a|}), "aa")
+      (('*', "WILDCHAR", ""), "")
+    ; (('*', "", "*"), "")
+    ; (('*', "WILDCHAR", "*"), "WILDCHAR")
+    ; (('*', "WILDCHAR", "**"), "WILDCHARWILDCHAR")
+    ; (('*', "WILDCHAR", "***"), "WILDCHARWILDCHARWILDCHAR")
+    ; (('"', "", ""), "")
+    ; (('"', "", "a"), "a")
+    ; (('"', "", {|"a"|}), "a")
+    ; (('"', "", {|a"a|}), "aa")
     ]
   in
   let test ((char, by, case), expected) =
     let name =
-      Printf.sprintf "replace %S by %S in %S is %S" char (String.escaped by)
+      Printf.sprintf "replace '%c' by %S in %S is %S" char (String.escaped by)
         (String.escaped case) (String.escaped expected)
     in
-    test_string (XString.replace char by) (name, case, expected)
+    test_string (XString.replace char ~by) (name, case, expected)
   in
   ("replace", List.map test spec)
 

ocaml/rrd2csv/src/rrd2csv.ml

@@ -185,13 +185,7 @@ module Ds_selector = struct
   let escape_metric s =
     let quote s = Printf.sprintf "\"%s\"" s in
     if String.contains s '"' then
-      quote
-        (Xstringext.String.map_unlikely s (function
-          | '\"' ->
-              Some "\"\""
-          | _ ->
-              None
-          ))
+      quote (Xstringext.String.replace '"' ~by:{|""|} s)
     else if String.contains s ',' || String.contains s '\n' then
       quote s
     else

ocaml/xapi/audit_log.ml

@@ -113,12 +113,8 @@ let transfer_all_audit_files fd_out ?filter since =
   atransfer_try_gz ""
 
 (* map the ISO8601 timestamp format into the one in our logs *)
-let log_timestamp_of_iso8601 iso8601_timestamp =
-  let module Xstringext = Xapi_stdext_std.Xstringext in
-  let step1 = iso8601_timestamp in
-  let step2 = Xstringext.String.replace "-" "" step1 in
-  let step3 = Xstringext.String.replace "Z" "" step2 in
-  step3
+let log_timestamp_of_iso8601 iso8601 =
+  Astring.String.filter (function '-' | 'Z' -> false | _ -> true) iso8601
 
 (*
  Assume that RBAC access for the session_id already verified by xapi_http.ml

ocaml/xapi/extauth_plugin_ADpbis.ml

@@ -132,9 +132,11 @@ let match_error_tag (lines : string list) =
 let extract_sid_from_group_list group_list =
   List.map
     (fun (_, v) ->
-      let v = Stringext.replace ")" "" v in
-      let v = Stringext.replace "sid =" "|" v in
-      let vs = Astring.String.cuts ~empty:false ~sep:"|" v in
+      let vs =
+        Astring.String.filter (function ')' -> false | _ -> true) v
+        |> Astring.String.cuts ~empty:false ~sep:"sid ="
+        |> List.concat_map (Astring.String.cuts ~empty:false ~sep:"|")
+      in
       let sid = String.trim (List.nth vs 1) in
       debug "extract_sid_from_group_list get sid=[%s]" sid ;
       sid
@@ -167,7 +169,8 @@ module AuthADlw : Auth_signature.AUTH_MODULE = struct
     Locking_helpers.Named_mutex.create "IS_SERVER_AVAILABLE"
 
   let splitlines s =
-    Astring.String.cuts ~empty:false ~sep:"\n" (Stringext.replace "#012" "\n" s)
+    Astring.String.cuts ~empty:false ~sep:"#012" s
+    |> List.concat_map (Astring.String.cuts ~empty:false ~sep:"\n")
 
   let pbis_common_with_password (password : string) (pbis_cmd : string)
       (pbis_args : string list) =
@@ -349,7 +352,7 @@ module AuthADlw : Auth_signature.AUTH_MODULE = struct
         if !exited_code <> 0 then (
           error "execute '%s': exit_code=[%d] output=[%s]" debug_cmd
             !exited_code
-            (Stringext.replace "\n" ";" !output) ;
+            (Stringext.replace '\n' ~by:";" !output) ;
           let split_to_words s =
             Astring.String.fields ~empty:false ~is_sep:is_word_sep s
           in
@@ -1126,8 +1129,8 @@ module AuthADlw : Auth_signature.AUTH_MODULE = struct
         in
         debug "execute %s: stdout=[%s],stderr=[%s]"
           pbis_force_domain_leave_script
-          (Stringext.replace "\n" ";" output)
-          (Stringext.replace "\n" ";" stderr)
+          (Stringext.replace '\n' ~by:";" output)
+          (Stringext.replace '\n' ~by:";" stderr)
       with e ->
         debug "exception executing %s: %s" pbis_force_domain_leave_script
           (ExnHelper.string_of_exn e)

ocaml/xapi/pciops.ml

@@ -126,7 +126,8 @@ let _unhide_pci ~__context pci =
       Printf.sprintf "(%s)" (Db.PCI.get_pci_id ~__context ~self:pci)
     in
     let new_value =
-      Xapi_stdext_std.Xstringext.String.replace bdf_paren "" raw_value
+      Astring.String.cuts ~empty:false ~sep:bdf_paren raw_value
+      |> String.concat ""
     in
     let cmd =
       match new_value with

ocaml/xapi/pvs_proxy_control.ml

@@ -21,7 +21,9 @@ open D
 let proxy_port_name vif =
   (* Interface names in Linux are at most 15 characters. We derive a
      name from the MAC address to ensure uniqueness, and make it fit. *)
-  let mac = Xapi_stdext_std.Xstringext.String.replace ":" "" vif.API.vIF_MAC in
+  let mac =
+    Astring.String.filter (function ':' -> false | _ -> true) vif.API.vIF_MAC
+  in
   Printf.sprintf "pvs%s" mac
 
 (** [proxies] returns all currently attached proxies *)

ocaml/xapi/rbac_audit.ml

@@ -462,9 +462,9 @@ let audit_line_of __context session_id allowed_denied ok_error result_error
          ?sexpr_of_args action permission
       )
   in
-  let line = Xapi_stdext_std.Xstringext.String.replace "\n" " " _line in
+  let line = Xapi_stdext_std.Xstringext.String.replace '\n' ~by:" " _line in
   (* no \n in line *)
-  let line = Xapi_stdext_std.Xstringext.String.replace "\r" " " line in
+  let line = Xapi_stdext_std.Xstringext.String.replace '\r' ~by:" " line in
   (* no \r in line *)
   let audit_line = append_line "%s" line in
   (*D.debug "line=%s, audit_line=%s" line audit_line;*)