File 0493-observer-Fix-parsing-of-monitor_node-2-in-cdv.patch of Package erlang

From ecd02ee73935ac6273b44ccf801183f52c116495 Mon Sep 17 00:00:00 2001
From: Lukas Larsson <lukas@erlang.org>
Date: Wed, 5 May 2021 09:07:19 +0200
Subject: [PATCH] observer: Fix parsing of monitor_node/2 in cdv

The link entry for monitor_node looks like this:

  {to,'node@name',[]}

and before this fix cdv crashed when encountering this.
---
 lib/observer/src/crashdump_viewer.erl  | 59 ++++++++++----------------
 lib/observer/test/crashdump_helper.erl |  3 +-
 2 files changed, 25 insertions(+), 37 deletions(-)

diff --git a/lib/observer/src/crashdump_viewer.erl b/lib/observer/src/crashdump_viewer.erl
index de418df0ab..2e3403325c 100644
--- a/lib/observer/src/crashdump_viewer.erl
+++ b/lib/observer/src/crashdump_viewer.erl
@@ -1346,12 +1346,12 @@ get_last_calls(Fd,<<>>,Acc,Lines) ->
     end.
 
 get_link_list(Fd) ->
-    case get_chunk(Fd) of
-	{ok,<<"[",Bin/binary>>} ->
+    case string(Fd) of
+	"[" ++ Rest ->
             #{links:=Links,
               mons:=Monitors,
               mon_by:=MonitoredBy} =
-                get_link_list(Fd,Bin,#{links=>[],mons=>[],mon_by=>[]}),
+                get_link_list(Rest,#{links=>[],mons=>[],mon_by=>[]}),
             {lists:reverse(Links),
              lists:reverse(Monitors),
              lists:reverse(MonitoredBy)};
@@ -1359,49 +1359,36 @@ get_link_list(Fd) ->
             {[],[],[]}
     end.
 
-get_link_list(Fd,<<NL:8,_/binary>>=Bin,Acc) when NL=:=$\r; NL=:=$\n->
-    skip(Fd,Bin),
-    Acc;
-get_link_list(Fd,Bin,Acc) ->
-    case binary:split(Bin,[<<", ">>,<<"]">>]) of
+get_link_list(Bin,Acc) ->
+    case string:split(Bin,", ") of
         [Link,Rest] ->
-            get_link_list(Fd,Rest,get_link(Link,Acc));
-        [Incomplete] ->
-            case get_chunk(Fd) of
-                {ok,More} ->
-                    get_link_list(Fd,<<Incomplete/binary,More/binary>>,Acc);
-                eof ->
-                    Acc
-            end
+            get_link_list(Rest,get_link(Link,Acc));
+        [Link] ->
+            get_link(string:trim(Link,trailing,"]"),Acc)
     end.
 
-get_link(<<"#Port",_/binary>>=PortBin,#{links:=Links}=Acc) ->
-    PortStr = binary_to_list(PortBin),
+get_link("#Port"++_=PortStr,#{links:=Links}=Acc) ->
     Acc#{links=>[{PortStr,PortStr}|Links]};
-get_link(<<"<",_/binary>>=PidBin,#{links:=Links}=Acc) ->
-    PidStr = binary_to_list(PidBin),
+get_link("<"++_=PidStr,#{links:=Links}=Acc) ->
     Acc#{links=>[{PidStr,PidStr}|Links]};
-get_link(<<"{to,",Bin/binary>>,#{mons:=Monitors}=Acc) ->
-    Acc#{mons=>[parse_monitor(Bin)|Monitors]};
-get_link(<<"{from,",Bin/binary>>,#{mon_by:=MonitoredBy}=Acc) ->
-    Acc#{mon_by=>[parse_monitor(Bin)|MonitoredBy]};
+get_link("{to," ++ Rest,#{mons:=Monitors}=Acc) ->
+    Acc#{mons=>[parse_monitor(Rest)|Monitors]};
+get_link("{from," ++ Rest,#{mon_by:=MonitoredBy}=Acc) ->
+    Acc#{mon_by=>[parse_monitor(Rest)|MonitoredBy]};
 get_link(Unexpected,Acc) ->
     io:format("WARNING: found unexpected data in link list:~n~ts~n",[Unexpected]),
     Acc.
 
-parse_monitor(MonBin) ->
-    case binary:split(MonBin,[<<",">>,<<"{">>,<<"}">>],[global]) of
-        [PidBin,RefBin,<<>>] ->
-            PidStr = binary_to_list(PidBin),
-            RefStr = binary_to_list(RefBin),
-            {PidStr,PidStr++" ("++RefStr++")"};
-        [<<>>,NameBin,NodeBin,<<>>,RefBin,<<>>] ->
+parse_monitor(Monitor) ->
+    case string:lexemes(Monitor,",{}") of
+        [Node,"[]"] ->
+            {Node,Node++" node monitor"};
+        [Pid,Ref] ->
+            {Pid,Pid++" ("++Ref++")"};
+        [Name,Node,Ref] ->
             %% Named process
-            NameStr = binary_to_list(NameBin),
-            NodeStr = binary_to_list(NodeBin),
-            PidStr = get_pid_from_name(NameStr,NodeStr),
-            RefStr = binary_to_list(RefBin),
-            {PidStr,"{"++NameStr++","++NodeStr++"} ("++RefStr++")"}
+            PidStr = get_pid_from_name(Name,Node),
+            {PidStr,"{"++Name++","++Node++"} ("++Ref++")"}
     end.
 
 get_pid_from_name(Name,Node) ->
diff --git a/lib/observer/test/crashdump_helper.erl b/lib/observer/test/crashdump_helper.erl
index 0f0947065a..cb1e1fba8a 100644
--- a/lib/observer/test/crashdump_helper.erl
+++ b/lib/observer/test/crashdump_helper.erl
@@ -37,7 +37,7 @@ n1_proc(Creator,N2,Pid2,Port2,L) when Pid2==x;length(L)<2->
 	P ->
 	    n1_proc(Creator,N2,Pid2,Port2,[P|L])
     end;
-n1_proc(Creator,_N2,Pid2,Port2,_L) ->
+n1_proc(Creator,N2,Pid2,Port2,_L) ->
     register(aaaaaaaa,self()),
     process_flag(save_calls,3),
     ets:new(cdv_test_ordset_table,[ordered_set]),
@@ -89,6 +89,7 @@ n1_proc(Creator,_N2,Pid2,Port2,_L) ->
     erlang:monitor(process,OtherPid),
     erlang:monitor(process,init), % named process
     erlang:monitor(process,Pid2),
+    monitor_node(N2, true),
 
     code:load_file(?MODULE),
 
-- 
2.26.2