Runtime: cleanup and fixes

Author: hhugo

runtime/js/fs.js

@@ -358,7 +358,7 @@ function caml_read_file_content(name) {
     var file = root.device.open(root.rest, { rdonly: 1 });
     var len = file.length();
     var buf = new Uint8Array(len);
-    file.read(buf, 0, len);
+    file.read(buf, 0, len, false);
     return caml_string_of_uint8_array(buf);
   }
   caml_raise_no_such_file(caml_jsstring_of_string(name));

runtime/js/fs_fake.js

@@ -293,7 +293,7 @@ class MlFakeDevice {
           this.nm(name),
         );
       file = this.content[name];
-      if (f.truncate) file.truncate();
+      if (f.truncate) file.truncate(0);
     } else if (f.create) {
       this.create_dir_if_needed(name);
       this.content[name] = new MlFakeFile(caml_create_bytes(0));
@@ -362,8 +362,9 @@ class MlFakeFile extends MlFile {
 
   truncate(len) {
     var old = this.data;
+    var old_len = caml_ml_bytes_length(old);
     this.data = caml_create_bytes(len | 0);
-    caml_blit_bytes(old, 0, this.data, 0, len);
+    caml_blit_bytes(old, 0, this.data, 0, Math.min(len, old_len));
   }
 
   length() {
@@ -393,12 +394,13 @@ class MlFakeFile extends MlFile {
     if (offset + len >= clen) {
       len = clen - offset;
     }
-    if (len) {
+    if (len > 0) {
       var data = caml_create_bytes(len | 0);
       caml_blit_bytes(this.data, offset, data, 0, len);
       buf.set(caml_uint8_array_of_bytes(data), pos);
+      return len;
     }
-    return len;
+    return 0;
   }
 }
 

runtime/js/fs_node.js

@@ -403,12 +403,13 @@ class MlNodeFd extends MlFile {
       var stats = this.fs.fstatSync(fd);
       flags.noSeek =
         stats.isCharacterDevice() || stats.isFIFO() || stats.isSocket();
+      this.offset = this.flags.append ? stats.size : 0;
     } catch (err) {
       // The fstat will fail on standard streams under Windows with node
       // 18 (and lower). See https://github.com/libuv/libuv/pull/3811.
       flags.noSeek = true;
+      this.offset = 0;
     }
-    this.offset = this.flags.append ? stats.size : 0;
     this.seeked = false;
   }
 

runtime/js/io.js

@@ -27,7 +27,7 @@ var caml_sys_fds = new Array(3);
 function caml_sys_close(fd) {
   var x = caml_sys_fds[fd];
   if (x) {
-    x.file.close();
+    x.file.close(false);
     delete caml_sys_fds[fd];
   }
   return 0;
@@ -360,6 +360,7 @@ function caml_refill(chan) {
       chan.buffer,
       chan.buffer_max,
       chan.buffer.length - chan.buffer_max,
+      false,
     );
     chan.offset += nread;
     chan.buffer_max += nread;
@@ -568,7 +569,7 @@ function caml_ml_flush(chanid) {
     );
   } else {
     for (var pos = 0; pos < chan.buffer_curr; ) {
-      pos += chan.file.write(chan.buffer, pos, chan.buffer_curr - pos);
+      pos += chan.file.write(chan.buffer, pos, chan.buffer_curr - pos, false);
     }
   }
   chan.offset += chan.buffer_curr;