From 42d8ccbdaf0d9f4d64d6a56a00ccbec016f09caa Mon Sep 17 00:00:00 2001
From: Hugo Heuzard <hugo.heuzard@gmail.com>
Date: Sun, 3 Mar 2024 15:11:41 +0100
Subject: [PATCH 1/5] Runtime: fix memory leak wrt channels

---
 runtime/io.js      | 95 ++++++++++++++++++++++++++++------------------
 runtime/parsing.js |  3 +-
 2 files changed, 61 insertions(+), 37 deletions(-)

diff --git a/runtime/io.js b/runtime/io.js
index 48a0aeb986..6b5a2c5056 100644
--- a/runtime/io.js
+++ b/runtime/io.js
@@ -25,8 +25,8 @@ var caml_sys_fds = new Array(3);
 //Provides: caml_sys_close
 //Requires: caml_sys_fds
 function caml_sys_close(fd) {
-  var file = caml_sys_fds[fd];
-  if(file) file.close();
+  var x = caml_sys_fds[fd];
+  if(x && x.file) x.file.close();
   delete caml_sys_fds[fd];
   return 0;
 }
@@ -41,10 +41,17 @@ function caml_sys_close(fd) {
 //Requires: caml_sys_fds
 //Requires: caml_sys_open_for_node
 function caml_sys_open_internal(file,idx) {
+  var chanid;
   if(idx == undefined){
     idx = caml_sys_fds.length;
+    chanid = Symbol(idx.toString());
   }
-  caml_sys_fds[idx] = file;
+  else if(caml_sys_fds[idx]){
+    chanid = caml_sys_fds[idx].chanid;
+  }
+  else
+    chanid = Symbol(idx.toString ());
+  caml_sys_fds[idx] = {file:file, chanid: chanid};
   return idx | 0;
 }
 function caml_sys_open (name, flags, _perms) {
@@ -90,21 +97,30 @@ function caml_sys_open (name, flags, _perms) {
 //Provides: caml_ml_set_channel_name
 //Requires: caml_ml_channels
 function caml_ml_set_channel_name(chanid, name) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   chan.name = name;
   return 0;
 }
 
 //Provides: caml_ml_channels
-var caml_ml_channels = new Array();
+var caml_ml_channels = new globalThis.WeakMap ()
+
+
+//Provides: caml_ml_channels_opened
+var caml_ml_channels_opened = new globalThis.Set()
 
 //Provides: caml_ml_out_channels_list
 //Requires: caml_ml_channels
+//Requires: caml_ml_channels_opened
+//Requires: caml_sys_fds
 function caml_ml_out_channels_list () {
   var l = 0;
-  for(var c = 0; c < caml_ml_channels.length; c++){
-    if(caml_ml_channels[c] && caml_ml_channels[c].opened && caml_ml_channels[c].out)
-      l=[0,caml_ml_channels[c].fd,l];
+  var keys = caml_ml_channels_opened.keys();
+  for(var k of keys){
+    var chan = caml_ml_channels.get(k);
+    if(chan.opened && chan.out){
+      l=[0,caml_sys_fds[chan.fd].chanid,l];
+    }
   }
   return l;
 }
@@ -114,8 +130,9 @@ function caml_ml_out_channels_list () {
 //Requires: caml_ml_channels, caml_sys_fds
 //Requires: caml_raise_sys_error
 //Requires: caml_sys_open
+//Requires: caml_ml_channels_opened
 function caml_ml_open_descriptor_out (fd) {
-  var file = caml_sys_fds[fd];
+  var s = caml_sys_fds[fd], file = s.file, chanid = s.chanid;
   if(file.flags.rdonly) caml_raise_sys_error("fd "+ fd + " is readonly");
   var buffered = (file.flags.buffered !== undefined) ? file.flags.buffered : 1;
   var channel = {
@@ -128,16 +145,18 @@ function caml_ml_open_descriptor_out (fd) {
     buffer:new Uint8Array(65536),
     buffered:buffered
   };
-  caml_ml_channels[channel.fd]=channel;
-  return channel.fd;
+  caml_ml_channels_opened.add(chanid);
+  caml_ml_channels.set(chanid,channel);
+  return chanid;
 }
 
 //Provides: caml_ml_open_descriptor_in
 //Requires: caml_ml_channels, caml_sys_fds
 //Requires: caml_raise_sys_error
 //Requires: caml_sys_open
+//Requires: caml_ml_channels_opened
 function caml_ml_open_descriptor_in (fd)  {
-  var file = caml_sys_fds[fd];
+  var s = caml_sys_fds[fd], file = s.file, chanid = s.chanid;
   if(file.flags.wronly) caml_raise_sys_error("fd "+ fd + " is writeonly");
   var refill = null;
   var channel = {
@@ -151,8 +170,9 @@ function caml_ml_open_descriptor_in (fd)  {
     buffer:new Uint8Array(65536),
     refill:refill
   };
-  caml_ml_channels[channel.fd]=channel;
-  return channel.fd;
+  caml_ml_channels_opened.add(chanid);
+  caml_ml_channels.set(chanid,channel);
+  return chanid;
 }
 
 
@@ -174,14 +194,14 @@ function caml_ml_open_descriptor_out_with_flags(fd, flags){
 //Requires: caml_ml_channels
 //Alias: win_filedescr_of_channel
 function caml_channel_descriptor(chanid){
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return chan.fd;
 }
 
 //Provides: caml_ml_set_binary_mode
 //Requires: caml_ml_channels
 function caml_ml_set_binary_mode(chanid,mode){
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   chan.file.flags.text = !mode
   chan.file.flags.binary = mode
   return 0;
@@ -191,7 +211,7 @@ function caml_ml_set_binary_mode(chanid,mode){
 //Requires: caml_ml_channels
 //Version: >= 5.2
 function caml_ml_is_binary_mode(chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return chan.file.flags.binary
 }
 
@@ -200,10 +220,12 @@ function caml_ml_is_binary_mode(chanid) {
 //Provides: caml_ml_close_channel
 //Requires: caml_ml_flush, caml_ml_channels
 //Requires: caml_sys_close
+//Requires: caml_ml_channels_opened
 function caml_ml_close_channel (chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   if(chan.opened) {
     chan.opened = false;
+    delete caml_ml_channels_opened.delete(chanid);
     caml_sys_close(chan.fd);
     chan.fd = -1;
     chan.buffer = new Uint8Array(0);
@@ -216,21 +238,21 @@ function caml_ml_close_channel (chanid) {
 //Provides: caml_ml_channel_size
 //Requires: caml_ml_channels
 function caml_ml_channel_size(chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return chan.file.length();
 }
 
 //Provides: caml_ml_channel_size_64
 //Requires: caml_int64_of_float,caml_ml_channels
 function caml_ml_channel_size_64(chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return caml_int64_of_float(chan.file.length ());
 }
 
 //Provides: caml_ml_set_channel_output
 //Requires: caml_ml_channels
 function caml_ml_set_channel_output(chanid,f) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   chan.output = (function (s) {f(s)});
   return 0;
 }
@@ -238,7 +260,7 @@ function caml_ml_set_channel_output(chanid,f) {
 //Provides: caml_ml_set_channel_refill
 //Requires: caml_ml_channels
 function caml_ml_set_channel_refill(chanid,f) {
-  caml_ml_channels[chanid].refill = f;
+  caml_ml_channels.get(chanid).refill = f;
   return 0;
 }
 
@@ -287,7 +309,7 @@ function caml_ml_input_bigarray (chanid, b, i, l) {
 //Provides: caml_ml_input_block
 //Requires: caml_refill, caml_ml_channels
 function caml_ml_input_block (chanid, ba, i, l) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   var n = l;
   var avail = chan.buffer_max - chan.buffer_curr;
   if(l <= avail) {
@@ -315,7 +337,7 @@ function caml_ml_input_block (chanid, ba, i, l) {
 //Requires: caml_refill, caml_failwith, caml_raise_end_of_file
 //Requires: caml_marshal_header_size
 function caml_input_value (chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   var header = new Uint8Array(caml_marshal_header_size);
   function block(buffer, offset, n) {
     var r = 0;
@@ -360,7 +382,7 @@ function caml_input_value_to_outside_heap(c) {
 //Requires: caml_raise_end_of_file, caml_array_bound_error
 //Requires: caml_ml_channels, caml_refill
 function caml_ml_input_char (chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   if(chan.buffer_curr >= chan.buffer_max){
     chan.buffer_curr = 0;
     chan.buffer_max = 0;
@@ -377,7 +399,7 @@ function caml_ml_input_char (chanid) {
 //Requires: caml_raise_end_of_file
 //Requires: caml_ml_input_char, caml_ml_channels
 function caml_ml_input_int (chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   var res = 0;
   for(var i = 0; i < 4; i++){
     res = (res << 8) + caml_ml_input_char(chanid) | 0;
@@ -388,7 +410,7 @@ function caml_ml_input_int (chanid) {
 //Provides: caml_seek_in
 //Requires: caml_raise_sys_error, caml_ml_channels
 function caml_seek_in(chanid, pos) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   if (chan.refill != null) caml_raise_sys_error("Illegal seek");
   if(pos >= chan.offset - chan.buffer_max
      && pos <= chan.offset
@@ -418,7 +440,7 @@ function caml_ml_seek_in_64(chanid,pos){
 //Provides: caml_pos_in
 //Requires: caml_ml_channels
 function caml_pos_in(chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return chan.offset - (chan.buffer_max - chan.buffer_curr) | 0;
 }
 
@@ -438,7 +460,7 @@ function caml_ml_pos_in_64(chanid) {
 //Requires: caml_array_bound_error
 //Requires: caml_ml_channels, caml_refill
 function caml_ml_input_scan_line(chanid){
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   var p = chan.buffer_curr;
   do {
     if(p >= chan.buffer_max) {
@@ -465,7 +487,7 @@ function caml_ml_input_scan_line(chanid){
 //Requires: caml_raise_sys_error, caml_ml_channels
 //Requires: caml_subarray_to_jsbytes
 function caml_ml_flush (chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   if(! chan.opened) caml_raise_sys_error("Cannot flush a closed channel");
   if(!chan.buffer || chan.buffer_curr == 0) return 0;
   if(chan.output) {
@@ -484,8 +506,9 @@ function caml_ml_flush (chanid) {
 //Requires: caml_ml_flush,caml_ml_bytes_length
 //Requires: caml_raise_sys_error, caml_ml_channels
 function caml_ml_output_ta(chanid,buffer,offset,len) {
-  var chan = caml_ml_channels[chanid];
-  if(! chan.opened) caml_raise_sys_error("Cannot output to a closed channel");
+  var chan = caml_ml_channels.get(chanid);
+  if(! chan.opened)
+    caml_raise_sys_error("Cannot output to a closed channel");
   buffer = buffer.subarray(offset, offset + len);
   if(chan.buffer_curr + buffer.length > chan.buffer.length) {
     var b = new Uint8Array(chan.buffer_curr + buffer.length);
@@ -569,7 +592,7 @@ function caml_output_value (chanid,v,flags) {
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_seek_out(chanid, pos){
   caml_ml_flush(chanid);
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   chan.offset = pos;
   return 0;
 }
@@ -589,7 +612,7 @@ function caml_ml_seek_out_64(chanid,pos){
 //Provides: caml_pos_out
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_pos_out(chanid) {
-  var chan = caml_ml_channels[chanid];
+  var chan = caml_ml_channels.get(chanid);
   return chan.offset + chan.buffer_curr
 }
 
@@ -618,13 +641,13 @@ function caml_ml_output_int (chanid,i) {
 //Provides: caml_ml_is_buffered
 //Requires: caml_ml_channels
 function caml_ml_is_buffered(chanid) {
-  return caml_ml_channels[chanid].buffered ? 1 : 0
+  return caml_ml_channels.get(chanid).buffered ? 1 : 0
 }
 
 //Provides: caml_ml_set_buffered
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_ml_set_buffered(chanid,v) {
-  caml_ml_channels[chanid].buffered = v;
+  caml_ml_channels.get(chanid).buffered = v;
   if(!v) caml_ml_flush(chanid);
   return 0
 }
diff --git a/runtime/parsing.js b/runtime/parsing.js
index 406f7c8498..b9de9926f4 100644
--- a/runtime/parsing.js
+++ b/runtime/parsing.js
@@ -24,6 +24,7 @@ var caml_parser_trace = 0;
 //Requires: caml_lex_array, caml_parser_trace,caml_jsstring_of_string
 //Requires: caml_ml_output, caml_ml_string_length, caml_string_of_jsbytes
 //Requires: caml_jsbytes_of_string, MlBytes
+//Requires: caml_sys_fds
 function caml_parse_engine(tables, env, cmd, arg)
 {
   var ERRCODE = 256;
@@ -84,7 +85,7 @@ function caml_parse_engine(tables, env, cmd, arg)
 
   function log(x) {
     var s = caml_string_of_jsbytes(x + "\n");
-    caml_ml_output(2, s, 0, caml_ml_string_length(s));
+    caml_ml_output(caml_sys_fds[2].chanid, s, 0, caml_ml_string_length(s));
   }
 
   function token_name(names, number)

From 6a562ee462ae5869f04700d7f4f58c35dfeee4a5 Mon Sep 17 00:00:00 2001
From: Hugo Heuzard <hugo.heuzard@gmail.com>
Date: Thu, 11 Apr 2024 08:38:52 +0200
Subject: [PATCH 2/5] WIP

---
 runtime/io.js | 74 ++++++++++++++++++++++++++++++++-------------------
 1 file changed, 46 insertions(+), 28 deletions(-)

diff --git a/runtime/io.js b/runtime/io.js
index 6b5a2c5056..6c2a019e8e 100644
--- a/runtime/io.js
+++ b/runtime/io.js
@@ -97,13 +97,31 @@ function caml_sys_open (name, flags, _perms) {
 //Provides: caml_ml_set_channel_name
 //Requires: caml_ml_channels
 function caml_ml_set_channel_name(chanid, name) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   chan.name = name;
   return 0;
+                             }
+
+  //Provides: caml_ml_channels
+var caml_ml_channels_weak = new globalThis.WeakMap ();
+var channels_handlers = {
+  get (target, prop, receiver) {
+    if(typeof prop == "symbol"){
+      return caml_ml_channels_weak.get(prop);
+    }
+    else {
+      console.log("cannot find", prop);
+      return
+    }
+  },
+  set (target, prop, new_val) {
+    if(typeof prop == "symbol"){
+      return caml_ml_channels_weak.set(prop, new_val);
+    }
+    return;
+  }
 }
-
-//Provides: caml_ml_channels
-var caml_ml_channels = new globalThis.WeakMap ()
+var caml_ml_channels = new globalThis.Proxy(caml_ml_channels_weak, channels_handlers);
 
 
 //Provides: caml_ml_channels_opened
@@ -117,7 +135,7 @@ function caml_ml_out_channels_list () {
   var l = 0;
   var keys = caml_ml_channels_opened.keys();
   for(var k of keys){
-    var chan = caml_ml_channels.get(k);
+    var chan = caml_ml_channels[k];
     if(chan.opened && chan.out){
       l=[0,caml_sys_fds[chan.fd].chanid,l];
     }
@@ -146,7 +164,7 @@ function caml_ml_open_descriptor_out (fd) {
     buffered:buffered
   };
   caml_ml_channels_opened.add(chanid);
-  caml_ml_channels.set(chanid,channel);
+  caml_ml_channels[chanid] = channel;
   return chanid;
 }
 
@@ -171,7 +189,7 @@ function caml_ml_open_descriptor_in (fd)  {
     refill:refill
   };
   caml_ml_channels_opened.add(chanid);
-  caml_ml_channels.set(chanid,channel);
+  caml_ml_channels[chanid] = channel;
   return chanid;
 }
 
@@ -194,14 +212,14 @@ function caml_ml_open_descriptor_out_with_flags(fd, flags){
 //Requires: caml_ml_channels
 //Alias: win_filedescr_of_channel
 function caml_channel_descriptor(chanid){
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return chan.fd;
 }
 
 //Provides: caml_ml_set_binary_mode
 //Requires: caml_ml_channels
 function caml_ml_set_binary_mode(chanid,mode){
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   chan.file.flags.text = !mode
   chan.file.flags.binary = mode
   return 0;
@@ -211,7 +229,7 @@ function caml_ml_set_binary_mode(chanid,mode){
 //Requires: caml_ml_channels
 //Version: >= 5.2
 function caml_ml_is_binary_mode(chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return chan.file.flags.binary
 }
 
@@ -222,7 +240,7 @@ function caml_ml_is_binary_mode(chanid) {
 //Requires: caml_sys_close
 //Requires: caml_ml_channels_opened
 function caml_ml_close_channel (chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   if(chan.opened) {
     chan.opened = false;
     delete caml_ml_channels_opened.delete(chanid);
@@ -238,21 +256,21 @@ function caml_ml_close_channel (chanid) {
 //Provides: caml_ml_channel_size
 //Requires: caml_ml_channels
 function caml_ml_channel_size(chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return chan.file.length();
 }
 
 //Provides: caml_ml_channel_size_64
 //Requires: caml_int64_of_float,caml_ml_channels
 function caml_ml_channel_size_64(chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return caml_int64_of_float(chan.file.length ());
 }
 
 //Provides: caml_ml_set_channel_output
 //Requires: caml_ml_channels
 function caml_ml_set_channel_output(chanid,f) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   chan.output = (function (s) {f(s)});
   return 0;
 }
@@ -260,7 +278,7 @@ function caml_ml_set_channel_output(chanid,f) {
 //Provides: caml_ml_set_channel_refill
 //Requires: caml_ml_channels
 function caml_ml_set_channel_refill(chanid,f) {
-  caml_ml_channels.get(chanid).refill = f;
+  caml_ml_channels[chanid].refill = f;
   return 0;
 }
 
@@ -309,7 +327,7 @@ function caml_ml_input_bigarray (chanid, b, i, l) {
 //Provides: caml_ml_input_block
 //Requires: caml_refill, caml_ml_channels
 function caml_ml_input_block (chanid, ba, i, l) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   var n = l;
   var avail = chan.buffer_max - chan.buffer_curr;
   if(l <= avail) {
@@ -337,7 +355,7 @@ function caml_ml_input_block (chanid, ba, i, l) {
 //Requires: caml_refill, caml_failwith, caml_raise_end_of_file
 //Requires: caml_marshal_header_size
 function caml_input_value (chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   var header = new Uint8Array(caml_marshal_header_size);
   function block(buffer, offset, n) {
     var r = 0;
@@ -382,7 +400,7 @@ function caml_input_value_to_outside_heap(c) {
 //Requires: caml_raise_end_of_file, caml_array_bound_error
 //Requires: caml_ml_channels, caml_refill
 function caml_ml_input_char (chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   if(chan.buffer_curr >= chan.buffer_max){
     chan.buffer_curr = 0;
     chan.buffer_max = 0;
@@ -399,7 +417,7 @@ function caml_ml_input_char (chanid) {
 //Requires: caml_raise_end_of_file
 //Requires: caml_ml_input_char, caml_ml_channels
 function caml_ml_input_int (chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   var res = 0;
   for(var i = 0; i < 4; i++){
     res = (res << 8) + caml_ml_input_char(chanid) | 0;
@@ -410,7 +428,7 @@ function caml_ml_input_int (chanid) {
 //Provides: caml_seek_in
 //Requires: caml_raise_sys_error, caml_ml_channels
 function caml_seek_in(chanid, pos) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   if (chan.refill != null) caml_raise_sys_error("Illegal seek");
   if(pos >= chan.offset - chan.buffer_max
      && pos <= chan.offset
@@ -440,7 +458,7 @@ function caml_ml_seek_in_64(chanid,pos){
 //Provides: caml_pos_in
 //Requires: caml_ml_channels
 function caml_pos_in(chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return chan.offset - (chan.buffer_max - chan.buffer_curr) | 0;
 }
 
@@ -460,7 +478,7 @@ function caml_ml_pos_in_64(chanid) {
 //Requires: caml_array_bound_error
 //Requires: caml_ml_channels, caml_refill
 function caml_ml_input_scan_line(chanid){
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   var p = chan.buffer_curr;
   do {
     if(p >= chan.buffer_max) {
@@ -487,7 +505,7 @@ function caml_ml_input_scan_line(chanid){
 //Requires: caml_raise_sys_error, caml_ml_channels
 //Requires: caml_subarray_to_jsbytes
 function caml_ml_flush (chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   if(! chan.opened) caml_raise_sys_error("Cannot flush a closed channel");
   if(!chan.buffer || chan.buffer_curr == 0) return 0;
   if(chan.output) {
@@ -506,7 +524,7 @@ function caml_ml_flush (chanid) {
 //Requires: caml_ml_flush,caml_ml_bytes_length
 //Requires: caml_raise_sys_error, caml_ml_channels
 function caml_ml_output_ta(chanid,buffer,offset,len) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   if(! chan.opened)
     caml_raise_sys_error("Cannot output to a closed channel");
   buffer = buffer.subarray(offset, offset + len);
@@ -592,7 +610,7 @@ function caml_output_value (chanid,v,flags) {
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_seek_out(chanid, pos){
   caml_ml_flush(chanid);
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   chan.offset = pos;
   return 0;
 }
@@ -612,7 +630,7 @@ function caml_ml_seek_out_64(chanid,pos){
 //Provides: caml_pos_out
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_pos_out(chanid) {
-  var chan = caml_ml_channels.get(chanid);
+  var chan = caml_ml_channels[chanid];
   return chan.offset + chan.buffer_curr
 }
 
@@ -641,13 +659,13 @@ function caml_ml_output_int (chanid,i) {
 //Provides: caml_ml_is_buffered
 //Requires: caml_ml_channels
 function caml_ml_is_buffered(chanid) {
-  return caml_ml_channels.get(chanid).buffered ? 1 : 0
+  return caml_ml_channels[chanid].buffered ? 1 : 0
 }
 
 //Provides: caml_ml_set_buffered
 //Requires: caml_ml_channels, caml_ml_flush
 function caml_ml_set_buffered(chanid,v) {
-  caml_ml_channels.get(chanid).buffered = v;
+  caml_ml_channels[chanid].buffered = v;
   if(!v) caml_ml_flush(chanid);
   return 0
 }

From f95dcf5abbf3918ea3fa7e7774e45b57474968ae Mon Sep 17 00:00:00 2001
From: Hugo Heuzard <hugo.heuzard@gmail.com>
Date: Thu, 11 Apr 2024 08:40:34 +0200
Subject: [PATCH 3/5] WIP

---
 runtime/io.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/runtime/io.js b/runtime/io.js
index 6c2a019e8e..ebea8b831a 100644
--- a/runtime/io.js
+++ b/runtime/io.js
@@ -525,8 +525,7 @@ function caml_ml_flush (chanid) {
 //Requires: caml_raise_sys_error, caml_ml_channels
 function caml_ml_output_ta(chanid,buffer,offset,len) {
   var chan = caml_ml_channels[chanid];
-  if(! chan.opened)
-    caml_raise_sys_error("Cannot output to a closed channel");
+  if(! chan.opened) caml_raise_sys_error("Cannot output to a closed channel");
   buffer = buffer.subarray(offset, offset + len);
   if(chan.buffer_curr + buffer.length > chan.buffer.length) {
     var b = new Uint8Array(chan.buffer_curr + buffer.length);

From 4cfb14280006797201631af728d96e6b80d4ca61 Mon Sep 17 00:00:00 2001
From: Hugo Heuzard <hugo.heuzard@gmail.com>
Date: Thu, 11 Apr 2024 10:00:37 +0200
Subject: [PATCH 4/5] WIP

---
 runtime/io.js | 56 ++++++++++++++++++++++++++-------------------------
 1 file changed, 29 insertions(+), 27 deletions(-)

diff --git a/runtime/io.js b/runtime/io.js
index ebea8b831a..680640ae1d 100644
--- a/runtime/io.js
+++ b/runtime/io.js
@@ -100,45 +100,52 @@ function caml_ml_set_channel_name(chanid, name) {
   var chan = caml_ml_channels[chanid];
   chan.name = name;
   return 0;
-                             }
+}
+
+//Provides: caml_ml_channels
+function caml_ml_channels_state() {
+  this.map = new globalThis.WeakMap ();
+  this.opened = new globalThis.Set();
+}
+caml_ml_channels_state.prototype.close = function (chanid) {
+  this.opened.delete(chanid);
+}
+caml_ml_channels_state.prototype.get = function (chanid) {
+  return this.map.get(chanid);
+}
+caml_ml_channels_state.prototype.set = function (chanid, val) {
+  if(val.opened) this.opened.add(chanid);
+  return this.map.set(chanid,val);
+}
+caml_ml_channels_state.prototype.all = function () {
+  return this.opened.values();
+}
 
-  //Provides: caml_ml_channels
-var caml_ml_channels_weak = new globalThis.WeakMap ();
 var channels_handlers = {
   get (target, prop, receiver) {
     if(typeof prop == "symbol"){
-      return caml_ml_channels_weak.get(prop);
-    }
-    else {
-      console.log("cannot find", prop);
-      return
+      return target.get(prop);
     }
+    return globalThis.Reflect.get(...arguments);
   },
-  set (target, prop, new_val) {
+  set (target, prop, new_val, receiver) {
     if(typeof prop == "symbol"){
-      return caml_ml_channels_weak.set(prop, new_val);
+      target.set(prop, new_val);
     }
-    return;
+    return true;
   }
 }
-var caml_ml_channels = new globalThis.Proxy(caml_ml_channels_weak, channels_handlers);
-
-
-//Provides: caml_ml_channels_opened
-var caml_ml_channels_opened = new globalThis.Set()
+var caml_ml_channels = new globalThis.Proxy(new caml_ml_channels_state, channels_handlers);
 
 //Provides: caml_ml_out_channels_list
 //Requires: caml_ml_channels
-//Requires: caml_ml_channels_opened
 //Requires: caml_sys_fds
 function caml_ml_out_channels_list () {
   var l = 0;
-  var keys = caml_ml_channels_opened.keys();
+  var keys = caml_ml_channels.all();
   for(var k of keys){
     var chan = caml_ml_channels[k];
-    if(chan.opened && chan.out){
-      l=[0,caml_sys_fds[chan.fd].chanid,l];
-    }
+    if(chan.opened && chan.out) l=[0,k,l];
   }
   return l;
 }
@@ -148,7 +155,6 @@ function caml_ml_out_channels_list () {
 //Requires: caml_ml_channels, caml_sys_fds
 //Requires: caml_raise_sys_error
 //Requires: caml_sys_open
-//Requires: caml_ml_channels_opened
 function caml_ml_open_descriptor_out (fd) {
   var s = caml_sys_fds[fd], file = s.file, chanid = s.chanid;
   if(file.flags.rdonly) caml_raise_sys_error("fd "+ fd + " is readonly");
@@ -163,7 +169,6 @@ function caml_ml_open_descriptor_out (fd) {
     buffer:new Uint8Array(65536),
     buffered:buffered
   };
-  caml_ml_channels_opened.add(chanid);
   caml_ml_channels[chanid] = channel;
   return chanid;
 }
@@ -172,7 +177,6 @@ function caml_ml_open_descriptor_out (fd) {
 //Requires: caml_ml_channels, caml_sys_fds
 //Requires: caml_raise_sys_error
 //Requires: caml_sys_open
-//Requires: caml_ml_channels_opened
 function caml_ml_open_descriptor_in (fd)  {
   var s = caml_sys_fds[fd], file = s.file, chanid = s.chanid;
   if(file.flags.wronly) caml_raise_sys_error("fd "+ fd + " is writeonly");
@@ -188,7 +192,6 @@ function caml_ml_open_descriptor_in (fd)  {
     buffer:new Uint8Array(65536),
     refill:refill
   };
-  caml_ml_channels_opened.add(chanid);
   caml_ml_channels[chanid] = channel;
   return chanid;
 }
@@ -238,12 +241,11 @@ function caml_ml_is_binary_mode(chanid) {
 //Provides: caml_ml_close_channel
 //Requires: caml_ml_flush, caml_ml_channels
 //Requires: caml_sys_close
-//Requires: caml_ml_channels_opened
 function caml_ml_close_channel (chanid) {
   var chan = caml_ml_channels[chanid];
   if(chan.opened) {
     chan.opened = false;
-    delete caml_ml_channels_opened.delete(chanid);
+    caml_ml_channels.close(chanid);
     caml_sys_close(chan.fd);
     chan.fd = -1;
     chan.buffer = new Uint8Array(0);

From 81814fec883248b4893799dd8cbf15e77d0d7ef0 Mon Sep 17 00:00:00 2001
From: Hugo Heuzard <hugo.heuzard@gmail.com>
Date: Thu, 11 Apr 2024 10:30:00 +0200
Subject: [PATCH 5/5] Changes

---
 CHANGES.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGES.md b/CHANGES.md
index a724718ded..cfc19fbcaa 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -18,6 +18,7 @@
 
 * Compiler: fix variable renaming for property binding and assignment target
 * Compiler: fix separate compilation of toplevels (broken since 5.7.0)
+* Runtime: no longer leak channels
 
 # 5.7.2 (2024-04-03) - Lille