Create erlang fallback for sendfile

Created erlang fallback for sendfile in gen_tcp and
moved sendfile from file to gen_tcp. Also created testcases
for testing all different options to sendfile.

For info about how sendfile should work see the BSD man pages
as they contain a more complete API than other *nixes.

1 files changed, 151 insertions, 2 deletions

diff --git a/lib/kernel/src/gen_tcp.erl b/lib/kernel/src/gen_tcp.erl
index 8ab18c01b4..56eca4cda4 100644
--- a/lib/kernel/src/gen_tcp.erl
+++ b/lib/kernel/src/gen_tcp.erl
@@ -22,11 +22,12 @@
 
 -export([connect/3, connect/4, listen/2, accept/1, accept/2,
 	 shutdown/2, close/1]).
--export([send/2, recv/2, recv/3, unrecv/2]).
+-export([send/2, recv/2, recv/3, unrecv/2, sendfile/2, sendfile/5]).
 -export([controlling_process/2]).
 -export([fdopen/2]).
 
 -include("inet_int.hrl").
+-include("file.hrl").
 
 -type option() ::
         {active,          true | false | once} |
@@ -105,8 +106,13 @@
         {tcp_module, module()} |
         option().
 -type socket() :: port().
+-type sendfile_option() :: {chunk_size, non_neg_integer()} |
+			   {headers, Hdrs :: list(iodata())} |
+			   {trailers, Tlrs :: list(iodata())} |
+			   sf_nodiskio | sf_mnowait | sf_sync.
 
--export_type([option/0, option_name/0, connect_option/0, listen_option/0]).
+-export_type([option/0, option_name/0, connect_option/0, listen_option/0,
+	      sendfile_option/0]).
 
 %%
 %% Connect a socket
@@ -305,6 +311,61 @@ unrecv(S, Data) when is_port(S) ->
     end.    
 
 %%
+%% Send data using sendfile
+%%
+
+-define(MAX_CHUNK_SIZE, (1 bsl 30)*2-1).
+
+-spec sendfile(File, Sock, Offset, Bytes, Opts) ->
+   {'ok', non_neg_integer()} | {'error', inet:posix()} when
+      File :: file:io_device(),
+      Sock :: socket(),
+      Offset :: non_neg_integer() | undefined,
+      Bytes :: non_neg_integer() | undefined,
+      Opts :: [sendfile_option()].
+sendfile(File, Sock, Offset, Bytes, Opts) when is_pid(File) ->
+    Ref = erlang:monitor(process, File),
+    File ! {file_request,self(),File,
+	    {sendfile,Sock,Offset,Bytes,Opts}},
+    receive
+	{file_reply,File,Reply} ->
+	    erlang:demonitor(Ref,[flush]),
+	    Reply;
+	{'DOWN', Ref, _, _, _} ->
+	    {error, terminated}
+    end;
+sendfile(File, Sock, Offset, Bytes, []) ->
+    sendfile(File, Sock, Offset, Bytes, ?MAX_CHUNK_SIZE, undefined, undefined,
+	     false, false, false);
+sendfile(File, Sock, Offset, Bytes, Opts) ->
+    ChunkSize0 = proplists:get_value(chunk_size, Opts, ?MAX_CHUNK_SIZE),
+    ChunkSize = if ChunkSize0 > ?MAX_CHUNK_SIZE ->
+			?MAX_CHUNK_SIZE;
+		   true -> ChunkSize0
+		end,
+    Headers = proplists:get_value(headers, Opts),
+    Trailers = proplists:get_value(trailers, Opts),
+    sendfile(File, Sock, Offset, Bytes, ChunkSize, Headers, Trailers,
+	     lists:member(sf_nodiskio,Opts),lists:member(sf_mnowait,Opts),
+	     lists:member(sf_sync,Opts)).
+
+%% sendfile/2
+-spec sendfile(File, Sock) ->
+   {'ok', non_neg_integer()} | {'error', inet:posix() | badarg}
+      when File :: file:name(),
+	   Sock :: socket().
+sendfile(File, Sock)  ->
+    case file:open(File, [read, raw, binary]) of
+	{error, Reason} ->
+	    {error, Reason};
+	{ok, Fd} ->
+	    {ok, #file_info{size = Bytes}} = file:read_file_info(File),
+	    Res = sendfile(Fd, Sock, 0, Bytes, []),
+	    file:close(Fd),
+	    Res
+    end.
+
+%%
 %% Set controlling process
 %%
 
@@ -354,3 +415,91 @@ mod([_|Opts], Address) ->
     mod(Opts, Address);
 mod([], Address) ->
     mod(Address).
+
+
+%% Internal sendfile functions
+sendfile(#file_descriptor{ module = Mod } = Fd, Sock, Offset, Bytes,
+	 ChunkSize, Headers, Trailers, Nodiskio, MNowait, Sync)
+  when is_port(Sock) ->
+    case Mod:sendfile(Fd, Sock, Offset, Bytes, ChunkSize, Headers, Trailers,
+		      Nodiskio, MNowait, Sync) of
+	{error, enotsup} ->
+	    sendfile_fallback(Fd, Sock, Offset, Bytes, ChunkSize,
+			      Headers, Trailers);
+	Else ->
+	    Else
+    end;
+sendfile(_,_,_,_,_,_,_,_,_,_) ->
+    {error, badarg}.
+
+%%%
+%% Sendfile Fallback
+%%%
+sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize,
+		  Headers, Trailers)
+  when is_list(Headers) == false ->
+    case sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize) of
+	{ok, BytesSent} when is_list(Trailers),is_integer(Headers) ->
+	    sendfile_send(Sock, Trailers, BytesSent+Headers);
+	{ok, BytesSent} when is_list(Trailers) ->
+	    sendfile_send(Sock, Trailers, BytesSent);
+	{ok, BytesSent} when is_integer(Headers) ->
+	    {ok, BytesSent + Headers};
+	Else ->
+	    Else
+    end;
+sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize, Headers, Trailers) ->
+    case sendfile_send(Sock, Headers, 0) of
+	{ok, BytesSent} ->
+	    sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize, BytesSent,
+			      Trailers);
+	Else ->
+	    Else
+    end.
+
+
+sendfile_fallback(File, Sock, undefined, Bytes, ChunkSize) ->
+    sendfile_fallback_int(File, Sock, Bytes, ChunkSize, 0);
+sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize) ->
+    {ok, CurrPos} = file:position(File, 0),
+    {ok, _NewPos} = file:position(File, {bof, Offset}),
+    Res = sendfile_fallback_int(File, Sock, Bytes, ChunkSize, 0),
+    file:position(File, {bof, CurrPos}),
+    Res.
+
+
+sendfile_fallback_int(_File, _Sock, BytesSent, _ChunkSize, BytesSent) ->
+    {ok, BytesSent};
+sendfile_fallback_int(File, Sock, Bytes, ChunkSize, BytesSent)
+  when Bytes > BytesSent; Bytes == undefined ->
+    Size = if Bytes == undefined ->
+		   ChunkSize;
+	       (Bytes - BytesSent + ChunkSize) > 0 ->
+		   Bytes - BytesSent;
+	      true ->
+		   ChunkSize
+	   end,
+    case file:read(File, Size) of
+	{ok, Data} ->
+	    case sendfile_send(Sock, Data, BytesSent) of
+		{ok,NewBytesSent} ->
+		    sendfile_fallback_int(
+		      File, Sock, Bytes, ChunkSize,
+		      NewBytesSent);
+		Error ->
+		    Error
+	    end;
+	eof ->
+	    {ok, BytesSent};
+	Error ->
+	    Error
+    end.
+
+sendfile_send(Sock, Data, Old) ->
+    Len = iolist_size(Data),
+    case send(Sock, Data) of
+	ok ->
+	    {ok, Len+Old};
+	Else ->
+	    Else
+    end.