Added Edoc markup for types and functions.

include/erleveldb.hrl

@@ -1,28 +1,138 @@
-%% Opaque resource types
+%% This file is part of ErLevelDB released under the MIT license. 
+%% See the LICENSE file for more information.
+
+%% @type db().
+%% An opaque handle to the database.
 -type db() :: term().
+
+
+%% @type iterator().
+%% An opaque handle to a database iterator.
 -type iterator() :: term().
+
+
+%% @type write_batch().
+%% An opaque handle to a write batch.
 -type write_batch() :: term().
+
+
+%% @type snapshot().
+%% An opaque handle to a database snapshot.
 -type snapshot() :: term().
 
-%% Database names and various options
+
+%% @type dbopts(). 
+%% Options for creating databases.
+%% <dl>
+%%   <dt>create_if_missing</dt>
+%%   <dd>
+%%     Create the database if it doesn't exist.
+%%   </dd>
+%%   <dt>error_if_exists</dt>
+%%   <dd>
+%%     The database must not exist before creating it.
+%%   </dd>
+%%   <dt>paranoid_checks</dt>
+%%   <dd>
+%%     Instruct the database code to check extensively for
+%%     corruption the the database files.
+%%   </dd>
+%%   <dt>{write_buffer_size, pos_integer()}</dt>
+%%   <dd>
+%%     The amount of RAM in bytes to use to buffer writes
+%%     before they are sorted and written to disk. Up to 2x
+%%     the <code>write_buffer_size</code> may be stored in
+%%     RAM at one time. The default is 4MiB.
+%%   </dd>
+%%   <dt>{max_open_files, pos_integer()}</dt>
+%%   <dd>
+%%     The maximum number of files to keep open for accessing
+%%     the database. The default is 100 open files.
+%%   </dd>
+%%   <dt>{cache_size, pos_integer()}</dt>
+%%   <dd>
+%%     The amount of RAM in bytes to use as a cache for
+%%     frequently read data blocks. The default is 8MiB.
+%%   </dd>
+%%   <dt>{block_size, pos_integer()}</dt>
+%%   <dd>
+%%     The size of a data block when writing to disk. The
+%%     default is 4KiB.
+%%   </dd>
+%%   <dt>{block_restart_interval, pos_integer()}</dt>
+%%   <dd>
+%%     The number of keys between restart points when delta
+%%     encoding key prefixes. The default is 16. This option
+%%     is usually left to the default.
+%%   </dd>
+%% </dl>
 -type dbopts() :: [
       create_if_missing
     | error_if_exists
     | paranoid_checks
     | {write_buffer_size, pos_integer()}
+    | {max_open_files, pos_integer()}
     | {cache_size, pos_integer()}
     | {block_size, pos_integer()}
     | {block_restart_interval, pos_integer()}
 ].
 
+
+%% @type readopts().
+%% Options when issuing read requests.
+%% <dl>
+%%   <dt>verify_checksums</dt>
+%%   <dd>
+%%     Verify the checksums for data read during this
+%%     request.
+%%   </dd>
+%%   <dt>skip_cache</dt>
+%%   <dd>
+%%     Do not store data read into the block cache. This
+%%     is mostly useful for bulk reads when you don't expect
+%%     to reread the data quickly.
+%%   </dd>
+%%   <dt>{snapshot, snapshot()}</dt>
+%%   <dd>
+%%     A database snapshot to read from. This will only return
+%%     results that existed at a given state of the database.
+%%   </dd>
+%% </dl>
 -type readopts() :: [
       verify_checksums
     | skip_cache
     | {snapshot, snapshot()}
 ].
 
+
+%% @type writeopts().
+%% Options when issuing write requests.
+%% <dl>
+%%   <dt>sync</dt>
+%%   <dd>
+%%     Call <code>fsync(2)</code> after the write
+%%     operation to flush the operating system buffers
+%%     to disk.
+%%   </dd>
+%%   <dt>snapshot</dt>
+%%   <dd>
+%%     Returns <code>{ok, snapshot()}</code> where the
+%%     snapshot refers to a logical point in time just
+%%     after this write complete but before any other
+%%     modification to the database.
+%%   </dd>
+%% </dl>
 -type writeopts() :: [sync | snapshot].
 
-%% Misc
+
+%% @type seek_dest().
+%% Iterators can seek to a provided key to start iterating
+%% from. The two atoms <code>first</code> and
+%% <code>last</code> can be used to seek to the very first or
+%% last key in the database.
 -type seek_dest() :: iolist() | first | last.
+
+
+%% @type error().
+%% The format for all errors reported by ErLevelDB.
 -type error() :: {error, any()}.