From: Jonathan Knowles <jonathan.knowles@eu.citrix.com>
Date: Fri, 20 Nov 2009 14:22:16 +0000 (+0000)
Subject: Adds functions "file_lines_{fold,iter}" to the Unixext module. These functions implem... 
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=944272fb81b500bc9d8d715a57230cb3026e09d6;p=xcp%2Fxen-api-libs.git

Adds functions "file_lines_{fold,iter}" to the Unixext module. These functions implement the standard "fold" and "iter" functions for all the lines in a file.

Signed-off-by: Jonathan Knowles <jonathan.knowles@eu.citrix.com>
---

diff --git a/stdext/unixext.ml b/stdext/unixext.ml
index ae0df74..e1a3734 100644
--- a/stdext/unixext.ml
+++ b/stdext/unixext.ml
@@ -85,18 +85,31 @@ let daemonize () =
 		end
 	| _ -> exit 0
 
-(** Run a function over every line in a file *)
-let readfile_line fn fname =
-	let fin = open_in fname in
+let file_lines_fold f start file_path =
+	let input = open_in file_path in
+	let rec fold accumulator =
+		let line =
+			try Some (input_line input)
+			with End_of_file -> None in
+		match line with
+			| Some line -> fold (f accumulator line)
+			| None -> accumulator in
+	finally
+		(fun () -> fold start)
+		(fun () -> close_in input)
+
+let file_lines_iter f file_path =
+	let input = open_in file_path in
 	try
 		while true do
-			let line = input_line fin in
-			fn line
-		done;
-		close_in fin;
+			let line = input_line input in
+			f line
+		done
 	with
-	| End_of_file -> close_in fin
-	| exn -> close_in fin; raise exn
+		| End_of_file -> close_in input
+		| exn -> close_in input; raise exn
+
+let readfile_line = file_lines_iter
 
 (** open a file, and make sure the close is always done *)
 let with_file file mode perms f =
diff --git a/stdext/unixext.mli b/stdext/unixext.mli
index d35d51b..8008bde 100644
--- a/stdext/unixext.mli
+++ b/stdext/unixext.mli
@@ -11,6 +11,8 @@
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU Lesser General Public License for more details.
  *)
+(** A collection of extensions to the [Unix] module. *)
+
 external _exit : int -> unit = "unix_exit"
 val unlink_safe : string -> unit
 val mkdir_safe : string -> Unix.file_perm -> unit
@@ -20,6 +22,15 @@ val pidfile_read : string -> int option
 val daemonize : unit -> unit
 val with_file : string -> Unix.open_flag list -> Unix.file_perm -> (Unix.file_descr -> 'a) -> 'a
 val with_directory : string -> (Unix.dir_handle -> 'a) -> 'a
+
+(** Folds function [f] over every line in the file at [file_path] using the
+starting value [start]. *)
+val file_lines_fold : ('a -> string -> 'a) -> 'a -> string -> 'a
+
+(** Applies function [f] to every line in the file at [file_path]. *)
+val file_lines_iter : (string -> unit) -> string -> unit
+
+(** Alias for function [file_lines_iter]. *)
 val readfile_line : (string -> 'a) -> string -> unit
 val read_whole_file : int -> int -> Unix.file_descr -> string
 val read_whole_file_to_string : string -> string