[logger] Add update_handler_config/3

This function is similar to set_handler_config/3, but calls the handler
callback changing_config/3 with the first parameter SetOrUpdate=update.

2 files changed, 55 insertions, 7 deletions

diff --git a/lib/kernel/doc/src/logger.xml b/lib/kernel/doc/src/logger.xml
index 8f54d0e54f..aa6e17f27b 100644
--- a/lib/kernel/doc/src/logger.xml
+++ b/lib/kernel/doc/src/logger.xml
@@ -748,6 +748,14 @@ start(_, []) ->
           exists, its associated value will be changed
           to the given value. If it does not exist, it will
           be added.</p>
+	<p>If the value is incomplete, which for example can be the
+	  case for the <c>config</c> key, it is up to the handler
+	  implementation how the unspecified parts are set. For all
+	  handlers in the Kernel application, unspecified data for
+	  the <c>config</c> key is set to default values. To update
+	  only specified data, and keep the existing configuration for
+	  the rest, use <seealso marker="#update_handler_config-3">
+	    <c>update_handler_config/3</c></seealso>.</p>
 	<p>See the definition of
 	  the <seealso marker="#type-handler_config">
 	    <c>handler_config()</c></seealso> type for more
@@ -933,6 +941,42 @@ logger:set_handler_config(HandlerId, maps:merge(Old, Config)).
     </func>
 
     <func>
+      <name name="update_handler_config" arity="3" clause_i="1"/>
+      <name name="update_handler_config" arity="3" clause_i="2"/>
+      <name name="update_handler_config" arity="3" clause_i="3"/>
+      <name name="update_handler_config" arity="3" clause_i="4"/>
+      <name name="update_handler_config" arity="3" clause_i="5"/>
+      <fsummary>Add or update configuration data for the specified
+        handler.</fsummary>
+      <type variable="HandlerId"/>
+      <type variable="Level" name_i="1"/>
+      <type variable="FilterDefault" name_i="2"/>
+      <type variable="Filters" name_i="3"/>
+      <type variable="Formatter" name_i="4"/>
+      <type variable="Config" name_i="5"/>
+      <type variable="Return"/>
+      <desc>
+        <p>Add or update configuration data for the specified
+          handler. If the given <c><anno>Key</anno></c> already
+          exists, its associated value will be changed
+          to the given value. If it does not exist, it will
+          be added.</p>
+	<p>If the value is incomplete, which for example can be the
+	  case for the <c>config</c> key, it is up to the handler
+	  implementation how the unspecified parts are set. For all
+	  handlers in the Kernel application, unspecified data for
+	  the <c>config</c> key is not changed. To reset unspecified
+	  data to default values,
+	  use <seealso marker="#set_handler_config-3">
+	    <c>set_handler_config/3</c></seealso>.</p>
+	<p>See the definition of
+	  the <seealso marker="#type-handler_config">
+	    <c>handler_config()</c></seealso> type for more
+	  information about the different parameters.</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="update_primary_config" arity="1"/>
       <fsummary>Update primary configuration data for Logger.</fsummary>
       <desc>
@@ -1063,7 +1107,7 @@ logger:set_process_metadata(maps:merge(logger:get_process_metadata(), Meta)).
 	  <seealso marker="#set_handler_config-2">
 	    <c>set_handler_config/2,3</c></seealso>, and <c>update</c>
 	  if it originates from <seealso marker="#update_handler_config-2">
-	    <c>update_handler_config/2</c></seealso>. The handler can
+	    <c>update_handler_config/2,3</c></seealso>. The handler can
 	  use this parameteter to decide how to update the value of
 	  the <c>config</c> field, that is, the handler specific
 	  configuration data. Typically, if <c>SetOrUpdate</c>
@@ -1150,7 +1194,7 @@ logger:set_process_metadata(maps:merge(logger:get_process_metadata(), Meta)).
 	  <item><seealso marker="logger#set_handler_config-2">
 	      <c>logger:set_handler_config/2,3</c></seealso></item>
 	  <item><seealso marker="logger#update_handler_config-2">
-	      <c>logger:updata_handler_config/2</c></seealso></item>
+	      <c>logger:updata_handler_config/2,3</c></seealso></item>
 	  <item><seealso marker="logger#update_formatter_config-2">
 	      <c>logger:update_formatter_config/2</c></seealso></item>
 	</list>
diff --git a/lib/kernel/doc/src/logger_chapter.xml b/lib/kernel/doc/src/logger_chapter.xml
index 7e88f82dad..777c37058e 100644
--- a/lib/kernel/doc/src/logger_chapter.xml
+++ b/lib/kernel/doc/src/logger_chapter.xml
@@ -555,7 +555,7 @@ logger:debug(#{got => connection_request, id => Id, state => State},
 	<item><seealso marker="logger#set_handler_config-2">
 	    <c>set_handler_config/2,3</c></seealso></item>
 	<item><seealso marker="logger#update_handler_config-2">
-	    <c>update_handler_config/2</c></seealso></item>
+	    <c>update_handler_config/2,3</c></seealso></item>
 	<item><seealso marker="logger#add_handler_filter-3">
 	    <c>add_handler_filter/3</c></seealso></item>
 	<item><seealso marker="logger#remove_handler_filter-2">
@@ -704,9 +704,13 @@ logger:debug(#{got => connection_request, id => Id, state => State},
           <item>
 	    <p>If <c>HandlerId</c> is <c>default</c>, then this entry
 	      modifies the default handler, equivalent to calling</p>
-	    <pre><seealso marker="logger#set_handler_config-2">
-		logger:set_handler_config(default, Module, HandlerConfig)
-	      </seealso></pre>
+	    <pre><seealso marker="logger#remove_handler-1">
+		logger:remove_handler(default)
+	    </seealso></pre>
+	    <p>followed by</p>
+	    <pre><seealso marker="logger#add_handler-3">
+		logger:add_handler(default, Module, HandlerConfig)
+	    </seealso></pre>
 	    <p>For all other values of <c>HandlerId</c>, this entry
 	      adds a new handler, equivalent to calling</p>
 	    <pre><seealso marker="logger:add_handler/3">
@@ -1043,7 +1047,7 @@ ok</pre>
     <p>When <seealso marker="logger#set_handler_config-2">
 	<c>logger:set_handler_config/2,3</c></seealso>
       or <seealso marker="logger#update_handler_config/2">
-	<c>logger:update_handler_config/2</c></seealso> is called,
+	<c>logger:update_handler_config/2,3</c></seealso> is called,
       Logger
       calls <c>HModule:changing_config(SetOrUpdate, OldConfig, NewConfig)</c>. If
       this function returns <c>{ok,NewConfig1}</c>, Logger