assert that calls to file functions actually succeed.

1) couch_file:sync could leave open fd's if close failed. Now we'll get a trace.
2) couch_file:append_term failing would be bad, so let's test that too.

backported from trunk r1150915

git-svn-id: https://svn.apache.org/repos/asf/couchdb/branches/1.1.x@1150918 13f79535-47bb-0310-9956-ffa450edef68

apps/couch/src/couch_db_updater.erl

@@ -52,7 +52,7 @@ init({DbName, Filepath, Fd, Options}) ->
 
 
 terminate(_Reason, Db) ->
-    couch_file:close(Db#db.fd),
+    ok = couch_file:close(Db#db.fd),
     couch_util:shutdown_sync(Db#db.compactor_pid),
     couch_util:shutdown_sync(Db#db.fd),
     ok.
@@ -513,9 +513,9 @@ flush_trees(#db{fd=Fd,header=Header}=Db,
                 {ok, NewSummaryPointer} =
                 case Header#db_header.disk_version < 4 of
                 true ->
-                    couch_file:append_term(Fd, {Doc#doc.body, DiskAtts});
+                    {ok, _} = couch_file:append_term(Fd, {Doc#doc.body, DiskAtts});
                 false ->
-                    couch_file:append_term_md5(Fd, {Doc#doc.body, DiskAtts})
+                    {ok, _} = couch_file:append_term_md5(Fd, {Doc#doc.body, DiskAtts})
                 end,
                 #leaf{
                     deleted = IsDeleted,

apps/couch/src/couch_file.erl

@@ -164,7 +164,7 @@ truncate(Fd, Pos) ->
 
 sync(Filepath) when is_list(Filepath) ->
     {ok, Fd} = file:open(Filepath, [append, raw]),
-    try file:sync(Fd) after file:close(Fd) end;
+    try ok = file:sync(Fd) after ok = file:close(Fd) end;
 sync(Fd) ->
     gen_server:call(Fd, sync, infinity).
 

apps/couch/src/couch_server_sup.erl

@@ -120,7 +120,7 @@ start_server(IniFiles) ->
             undefined -> [];
             Uri -> io_lib:format("~s~n", [Uri])
             end end || Uri <- Uris],
-        file:write_file(UriFile, Lines)
+        ok = file:write_file(UriFile, Lines)
     end,
 
     {ok, Pid}.