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diff --git a/apps/couch/src/couch_config_writer.erl b/apps/couch/src/couch_config_writer.erl
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+% Licensed under the Apache License, Version 2.0 (the "License"); you may not
+% use this file except in compliance with the License. You may obtain a copy of
+% the License at
+%
+%   http://www.apache.org/licenses/LICENSE-2.0
+%
+% Unless required by applicable law or agreed to in writing, software
+% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+% License for the specific language governing permissions and limitations under
+% the License.
+
+%% @doc Saves a Key/Value pair to a ini file. The Key consists of a Section
+%%      and Option combination. If that combination is found in the ini file
+%%      the new value replaces the old value. If only the Section is found the
+%%      Option and value combination is appended to the Section. If the Section
+%%      does not yet exist in the ini file, it is added and the Option/Value
+%%      pair is appended.
+%% @see couch_config
+
+-module(couch_config_writer).
+
+-export([save_to_file/2]).
+
+%% @spec save_to_file(
+%%           Config::{{Section::string(), Option::string()}, Value::string()},
+%%           File::filename()) -> ok
+%% @doc Saves a Section/Key/Value triple to the ini file File::filename()
+save_to_file({{Section, Key}, Value}, File) ->
+    {ok, OldFileContents} = file:read_file(File),
+    Lines = re:split(OldFileContents, "\r\n|\n|\r|\032", [{return, list}]),
+
+    SectionLine = "[" ++ Section ++ "]",
+    {ok, Pattern} = re:compile(["^(", Key, "\\s*=)|\\[[a-zA-Z0-9\_-]*\\]"]),
+
+    NewLines = process_file_lines(Lines, [], SectionLine, Pattern, Key, Value),
+    NewFileContents = reverse_and_add_newline(strip_empty_lines(NewLines), []),
+    case file:write_file(File, NewFileContents) of
+    ok ->
+        ok;
+    {error, eacces} ->
+        {file_permission_error, File};
+    Error ->
+        Error
+    end.
+
+
+process_file_lines([Section|Rest], SeenLines, Section, Pattern, Key, Value) ->
+    process_section_lines(Rest, [Section|SeenLines], Pattern, Key, Value);
+
+process_file_lines([Line|Rest], SeenLines, Section, Pattern, Key, Value) ->
+    process_file_lines(Rest, [Line|SeenLines], Section, Pattern, Key, Value);
+
+process_file_lines([], SeenLines, Section, _Pattern, Key, Value) ->
+    % Section wasn't found.  Append it with the option here.
+    [Key ++ " = " ++ Value, Section, "" | strip_empty_lines(SeenLines)].
+
+
+process_section_lines([Line|Rest], SeenLines, Pattern, Key, Value) ->
+    case re:run(Line, Pattern, [{capture, all_but_first}]) of
+    nomatch -> % Found nothing interesting. Move on.
+        process_section_lines(Rest, [Line|SeenLines], Pattern, Key, Value);
+    {match, []} -> % Found another section. Append the option here.
+        lists:reverse(Rest) ++
+        [Line, "", Key ++ " = " ++ Value | strip_empty_lines(SeenLines)];
+    {match, _} -> % Found the option itself. Replace it.
+        lists:reverse(Rest) ++ [Key ++ " = " ++ Value | SeenLines]
+    end;
+
+process_section_lines([], SeenLines, _Pattern, Key, Value) ->
+    % Found end of file within the section. Append the option here.
+    [Key ++ " = " ++ Value | strip_empty_lines(SeenLines)].
+
+
+reverse_and_add_newline([Line|Rest], Content) ->
+    reverse_and_add_newline(Rest, [Line, "\n", Content]);
+
+reverse_and_add_newline([], Content) ->
+    Content.
+
+
+strip_empty_lines(["" | Rest]) ->
+    strip_empty_lines(Rest);
+
+strip_empty_lines(All) ->
+    All.