diff options
Diffstat (limited to 'lib/stdlib/doc/src')
| -rw-r--r-- | lib/stdlib/doc/src/filename.xml | 29 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/gen_statem.xml | 167 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/notes.xml | 104 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/sys.xml | 6 |
4 files changed, 256 insertions, 50 deletions
diff --git a/lib/stdlib/doc/src/filename.xml b/lib/stdlib/doc/src/filename.xml index 2a413835d0..f20500709c 100644 --- a/lib/stdlib/doc/src/filename.xml +++ b/lib/stdlib/doc/src/filename.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>1997</year><year>2016</year> + <year>1997</year><year>2017</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -511,6 +511,33 @@ true </func> <func> + <name name="safe_relative_path" arity="1"/> + <fsummary>Sanitize a relative path to avoid directory traversal attacks.</fsummary> + <desc> + <p>Sanitizes the relative path by eliminating ".." and "." + components to protect against directory traversal attacks. + Either returns the sanitized path name, or the atom + <c>unsafe</c> if the path is unsafe. + The path is considered unsafe in the following circumstances:</p> + <list type="bulleted"> + <item><p>The path is not relative.</p></item> + <item><p>A ".." component would climb up above the root of + the relative path.</p></item> + </list> + <p><em>Examples:</em></p> + <pre> +1> <input>filename:safe_relative_path("dir/sub_dir/..").</input> +"dir" +2> <input>filename:safe_relative_path("dir/..").</input> +[] +3> <input>filename:safe_relative_path("dir/../..").</input> +unsafe +4> <input>filename:safe_relative_path("/abs/path").</input> +unsafe</pre> + </desc> + </func> + + <func> <name name="split" arity="1"/> <fsummary>Split a filename into its path components.</fsummary> <desc> diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml index fd498ee82e..5eb13db1aa 100644 --- a/lib/stdlib/doc/src/gen_statem.xml +++ b/lib/stdlib/doc/src/gen_statem.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>2016</year> + <year>2016-2017</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -587,8 +587,8 @@ handle_event(_, _, State, Data) -> <name name="state_enter"/> <desc> <p> - If the state machine should use <em>state enter calls</em> - is selected when starting the <c>gen_statem</c> + Whether the state machine should use <em>state enter calls</em> + or not is selected when starting the <c>gen_statem</c> and after code change using the return value from <seealso marker="#Module:callback_mode/0"><c>Module:callback_mode/0</c></seealso>. </p> @@ -606,7 +606,16 @@ handle_event(_, _, State, Data) -> See <seealso marker="#Module:StateName/3"><c>Module:StateName/3</c></seealso> and - <seealso marker="#Module:handle_event/4"><c>Module:handle_event/4</c></seealso>. + <seealso marker="#Module:handle_event/4"><c>Module:handle_event/4</c></seealso>. + Such a call can be repeated by returning a + <seealso marker="#type-state_callback_result"> + <c>repeat_state</c> + </seealso> + or + <seealso marker="#type-state_callback_result"> + <c>repeat_state_and_data</c> + </seealso> + tuple from the state callback. </p> <p> If @@ -625,7 +634,8 @@ handle_event(_, _, State, Data) -> right before entering the initial state even though this formally is not a state change. In this case <c>OldState</c> will be the same as <c>State</c>, - which can not happen for a subsequent state change. + which can not happen for a subsequent state change, + but will happen when repeating the state enter call. </p> </desc> </datatype> @@ -640,7 +650,15 @@ handle_event(_, _, State, Data) -> <list type="ordered"> <item> <p> - If the state changes or is the initial state, and + If the state changes, is the initial state, + <seealso marker="#type-state_callback_result"> + <c>repeat_state</c> + </seealso> + or + <seealso marker="#type-state_callback_result"> + <c>repeat_state_and_data</c> + </seealso> + is used, and also <seealso marker="#type-state_enter"><em>state enter calls</em></seealso> are used, the <c>gen_statem</c> calls the new state callback with arguments @@ -983,6 +1001,33 @@ handle_event(_, _, State, Data) -> </desc> </datatype> <datatype> + <name name="init_result"/> + <desc> + <p> + For a succesful initialization, + <c><anno>State</anno></c> is the initial + <seealso marker="#type-state"><c>state()</c></seealso> + and <c><anno>Data</anno></c> the initial server + <seealso marker="#type-data"><c>data()</c></seealso> + of the <c>gen_statem</c>. + </p> + <p> + The <seealso marker="#type-action"><c>Actions</c></seealso> + are executed when entering the first + <seealso marker="#type-state">state</seealso> just as for a + <seealso marker="#state callback">state callback</seealso>, + except that the action <c>postpone</c> is forced to + <c>false</c> since there is no event to postpone. + </p> + <p> + For an unsuccesful initialization, + <c>{stop,<anno>Reason</anno>}</c> + or <c>ignore</c> should be used; see + <seealso marker="#start_link/3"><c>start_link/3,4</c></seealso>. + </p> + </desc> + </datatype> + <datatype> <name name="state_enter_result"/> <desc> <p> @@ -1068,6 +1113,37 @@ handle_event(_, _, State, Data) -> <c>{next_state,CurrentState,CurrentData,<anno>Actions</anno>}</c>. </p> </item> + <tag><c>repeat_state</c></tag> + <item> + <p> + The <c>gen_statem</c> keeps the current state, or + does a state transition to the current state if you like, + sets <c><anno>NewData</anno></c>, + and executes all <c><anno>Actions</anno></c>. + If the <c>gen_statem</c> runs with + <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, + the state enter call is repeated, see type + <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>, + otherwise <c>repeat_state</c> is the same as + <c>keep_state</c>. + </p> + </item> + <tag><c>repeat_state_and_data</c></tag> + <item> + <p> + The <c>gen_statem</c> keeps the current state and data, or + does a state transition to the current state if you like, + and executes all <c><anno>Actions</anno></c>. + This is the same as + <c>{repeat_state,CurrentData,<anno>Actions</anno>}</c>. + If the <c>gen_statem</c> runs with + <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, + the state enter call is repeated, see type + <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>, + otherwise <c>repeat_state_and_data</c> is the same as + <c>keep_state_and_data</c>. + </p> + </item> <tag><c>stop</c></tag> <item> <p> @@ -1609,29 +1685,33 @@ handle_event(_, _, State, Data) -> It is recommended to use an atom as <c>Reason</c> since it will be wrapped in an <c>{error,Reason}</c> tuple. </p> + <p> + Also note when upgrading a <c>gen_statem</c>, + this function and hence + the <c>Change={advanced,Extra}</c> parameter in the + <seealso marker="sasl:appup"><c>appup</c></seealso> file + is not only needed to update the internal state + or to act on the <c>Extra</c> argument. + It is also needed if an upgrade or downgrade should change + <seealso marker="#type-callback_mode"><em>callback mode</em></seealso>, + or else the callback mode after the code change + will not be honoured, + most probably causing a server crash. + </p> </desc> </func> <func> - <name>Module:init(Args) -> Result</name> + <name>Module:init(Args) -> Result(StateType)</name> <fsummary> Optional function for initializing process and internal state. </fsummary> <type> <v>Args = term()</v> - <v>Result = {ok,State,Data}</v> - <v> | {ok,State,Data,Actions}</v> - <v> | {stop,Reason} | ignore</v> - <v>State = <seealso marker="#type-state">state()</seealso></v> - <v> - Data = <seealso marker="#type-data">data()</seealso> - </v> <v> - Actions = - [<seealso marker="#type-action">action()</seealso>] | - <seealso marker="#type-action">action()</seealso> + Result(StateType) = + <seealso marker="#type-init_result">init_result(StateType)</seealso> </v> - <v>Reason = term()</v> </type> <desc> <marker id="Module:init-1"/> @@ -1644,30 +1724,9 @@ handle_event(_, _, State, Data) -> the implementation state and server data. </p> <p> - <c>Args</c> is the <c>Args</c> argument provided to the start + <c>Args</c> is the <c>Args</c> argument provided to that start function. </p> - <p> - If the initialization is successful, the function is to - return <c>{ok,State,Data}</c> or - <c>{ok,State,Data,Actions}</c>. - <c>State</c> is the initial - <seealso marker="#type-state"><c>state()</c></seealso> - and <c>Data</c> the initial server - <seealso marker="#type-data"><c>data()</c></seealso>. - </p> - <p> - The <seealso marker="#type-action"><c>Actions</c></seealso> - are executed when entering the first - <seealso marker="#type-state">state</seealso> just as for a - <seealso marker="#state callback">state callback</seealso>. - </p> - <p> - If the initialization fails, - the function is to return <c>{stop,Reason}</c> - or <c>ignore</c>; see - <seealso marker="#start_link/3"><c>start_link/3,4</c></seealso>. - </p> <note> <p> This callback is optional, so a callback module does not need @@ -1873,22 +1932,33 @@ handle_event(_, _, State, Data) -> <seealso marker="#type-enter_action">actions</seealso> that may be returned: <seealso marker="#type-postpone"><c>postpone()</c></seealso> - and + is not allowed since a <em>state enter call</em> is not + an event so there is no event to postpone, and <seealso marker="#type-action"><c>{next_event,_,_}</c></seealso> - are not allowed. + is not allowed since using <em>state enter calls</em> + should not affect how events are consumed and produced. You may also not change states from this call. Should you return <c>{next_state,NextState, ...}</c> with <c>NextState =/= State</c> the <c>gen_statem</c> crashes. - You are advised to use <c>{keep_state,...}</c> or - <c>keep_state_and_data</c>. + It is possible to use <c>{repeat_state, ...}</c>, + <c>{repeat_state_and_data,_}</c> or + <c>repeat_state_and_data</c> but all of them makes little + sense since you immediately will be called again with a new + <em>state enter call</em> making this just a weird way + of looping, and there are better ways to loop in Erlang. + You are advised to use <c>{keep_state,...}</c>, + <c>{keep_state_and_data,_}</c> or + <c>keep_state_and_data</c> since you can not change states + from a <em>state enter call</em> anyway. </p> <p> Note the fact that you can use <seealso marker="erts:erlang#throw/1"><c>throw</c></seealso> to return the result, which can be useful. For example to bail out with <c>throw(keep_state_and_data)</c> - from deep within complex code that is in no position to - return <c>{next_state,State,Data}</c>. + from deep within complex code that can not + return <c>{next_state,State,Data}</c> because + <c>State</c> or <c>Data</c> is no longer in scope. </p> </desc> </func> @@ -1903,6 +1973,11 @@ handle_event(_, _, State, Data) -> <v>Ignored = term()</v> </type> <desc> + <note> + <p>This callback is optional, so callback modules need not + export it. The <c>gen_statem</c> module provides a default + implementation without cleanup.</p> + </note> <p> This function is called by a <c>gen_statem</c> when it is about to terminate. It is to be the opposite of diff --git a/lib/stdlib/doc/src/notes.xml b/lib/stdlib/doc/src/notes.xml index 0143686bb2..bb35224182 100644 --- a/lib/stdlib/doc/src/notes.xml +++ b/lib/stdlib/doc/src/notes.xml @@ -31,6 +31,110 @@ </header> <p>This document describes the changes made to the STDLIB application.</p> +<section><title>STDLIB 3.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>An escript with only two lines would not work.</p> + <p> + Own Id: OTP-14098</p> + </item> + <item> + <p> Characters (<c>$char</c>) can be used in constant + pattern expressions. They can also be used in types and + contracts. </p> + <p> + Own Id: OTP-14103 Aux Id: ERL-313 </p> + </item> + <item> + <p> The signatures of <c>erl_parse:anno_to_term/1</c> and + <c>erl_parse:anno_from_term/1</c> are corrected. Using + these functions no longer results in false Dialyzer + warnings. </p> + <p> + Own Id: OTP-14131</p> + </item> + <item> + <p>Pretty-printing of maps is improved. </p> + <p> + Own Id: OTP-14175 Aux Id: seq13277 </p> + </item> + <item> + <p>If any of the following functions in the <c>zip</c> + module crashed, a file would be left open: + <c>extract()</c>, <c>unzip()</c>, <c>create()</c>, or + <c>zip()</c>. This has been corrected.</p> + <p>A <c>zip</c> file having a "Unix header" could not be + unpacked.</p> + <p> + Own Id: OTP-14189 Aux Id: ERL-348, ERL-349 </p> + </item> + <item> + <p> Improve the Erlang shell's tab-completion of long + names. </p> + <p> + Own Id: OTP-14200 Aux Id: ERL-352 </p> + </item> + <item> + <p> + The reference manual for <c>sys</c> had some faulty + information about the 'get_modules' message used by + processes where modules change dynamically during + runtime. The documentation is now corrected.</p> + <p> + Own Id: OTP-14248 Aux Id: ERL-367 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Bug fixes, new features and improvements to gen_statem:</p> + <p> + A new type init_result/1 has replaced the old + init_result/0, so if you used that old type (that was + never documented) you have to change your code, which may + be regarded as a potential incompatibility.</p> + <p> + Changing callback modes after code change did not work + since the new callback mode was not recorded. This bug + has been fixed.</p> + <p> + The event types state_timeout and {call,From} could not + be generated with a {next_event,EventType,EventContent} + action since they did not pass the runtime type check. + This bug has now been corrected.</p> + <p> + State entry calls can now be repeated using (new) state + callback returns {repeat_state,...}, + {repeat_state_and_data,_} and repeat_state_and_data.</p> + <p> + There have been lots of code cleanup in particular + regarding timer handling. For example is async + cancel_timer now used. Error handling has also been + cleaned up.</p> + <p> + To align with probable future changes to the rest of + gen_*, terminate/3 has now got a fallback and + code_change/4 is not mandatory.</p> + <p> + Own Id: OTP-14114</p> + </item> + <item> + <p><c>filename:safe_relative_path/1</c> to sanitize a + relative path has been added.</p> + <p> + Own Id: OTP-14215</p> + </item> + </list> + </section> + +</section> + <section><title>STDLIB 3.2</title> <section><title>Fixed Bugs and Malfunctions</title> diff --git a/lib/stdlib/doc/src/sys.xml b/lib/stdlib/doc/src/sys.xml index 9091a46df9..0fed649660 100644 --- a/lib/stdlib/doc/src/sys.xml +++ b/lib/stdlib/doc/src/sys.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>1996</year><year>2016</year> + <year>1996</year><year>2017</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -83,8 +83,8 @@ <p>If the modules used to implement the process change dynamically during runtime, the process must understand one more message. An example is the <seealso marker="gen_event"><c>gen_event</c></seealso> - processes. The message is <c>{get_modules, From}</c>. - The reply to this message is <c>From ! {modules, Modules}</c>, where + processes. The message is <c>{_Label, {From, Ref}, get_modules}</c>. + The reply to this message is <c>From ! {Ref, Modules}</c>, where <c>Modules</c> is a list of the currently active modules in the process.</p> <p>This message is used by the release handler to find which |