Fixed issue #632 async/await (#633)

Co-authored-by: Fabian <copy@copy.sh>

examples/arch.html

@@ -31,21 +31,15 @@ window.onload = function()
         ].join(" "),
     });
 
-    document.getElementById("save_file").onclick = function()
+    document.getElementById("save_file").onclick = async function()
     {
-        emulator.save_state(function(error, new_state)
-        {
-            if(error)
-            {
-                throw error;
-            }
+        const new_state = await emulator.save_state();
 
-            var a = document.createElement("a");
-            a.download = "v86state.bin";
-            a.href = window.URL.createObjectURL(new Blob([new_state]));
-            a.dataset.downloadurl = "application/octet-stream:" + a.download + ":" + a.href;
-            a.click();
-        });
+        var a = document.createElement("a");
+        a.download = "v86state.bin";
+        a.href = window.URL.createObjectURL(new Blob([new_state]));
+        a.dataset.downloadurl = "application/octet-stream:" + a.download + ":" + a.href;
+        a.click();
 
         this.blur();
     };
@@ -57,9 +51,9 @@ window.onload = function()
             var filereader = new FileReader();
             emulator.stop();
 
-            filereader.onload = function(e)
+            filereader.onload = async function(e)
             {
-                emulator.restore_state(e.target.result);
+                await emulator.restore_state(e.target.result);
                 emulator.run();
             };
 

examples/lang.html

@@ -36,7 +36,7 @@ window.onload = function()
 
     document.getElementById("status").textContent += ".";
 
-    emulator.add_listener("emulator-ready", function()
+    emulator.add_listener("emulator-ready", async function()
     {
         document.getElementById("status").textContent += ".";
 
@@ -45,28 +45,20 @@ window.onload = function()
 
         buffer.set(code.split("").map(function(chr) { return chr.charCodeAt(0); }));
 
-        emulator.create_file("/root/code.js", buffer, function(error)
-        {
-            if(error) throw error;
-
-            emulator.serial0_send("node /root/code.js > /root/out.txt 2> /root/out.txt\n");
-        });
+        await emulator.create_file("/root/code.js", buffer);
+        emulator.serial0_send("node /root/code.js > /root/out.txt 2> /root/out.txt\n");
     });
 
     var serial_out = "";
-    emulator.add_listener("serial0-output-char", function(chr)
+    emulator.add_listener("serial0-output-char", async function(chr)
     {
         serial_out += chr;
         //document.getElementById("output").textContent += chr;
 
         if(serial_out.endsWith("root@nyu"))
         {
-            emulator.read_file("/root/out.txt", function(error, data)
-            {
-                if(error) throw error;
-
-                document.getElementById("output").textContent += String.fromCharCode.apply(this, data);
-            });
+            const data = await emulator.read_file("/root/out.txt");
+            document.getElementById("output").textContent += String.fromCharCode.apply(this, data);
         }
     });
 }

examples/nodejs_state.js

@@ -36,7 +36,7 @@ emulator.add_listener("serial0-output-char", function(chr)
 
 var state;
 
-process.stdin.on("data", function(c)
+process.stdin.on("data", async function(c)
 {
     if(c === "\u0003")
     {
@@ -47,16 +47,8 @@ process.stdin.on("data", function(c)
     else if(c === "\x1b\x4f\x51")
     {
         // f2
-        emulator.save_state(function(err, s)
-        {
-            console.log("--- Saved ---");
-            if(err)
-            {
-                throw err;
-            }
-
-            state = s;
-        });
+        state = await emulator.save_state();
+        console.log("--- Saved ---");
     }
     else if(c === "\x1b\x4f\x52")
     {
@@ -64,7 +56,7 @@ process.stdin.on("data", function(c)
         if(state)
         {
             console.log("--- Restored ---");
-            emulator.restore_state(state);
+            await emulator.restore_state(state);
         }
     }
     else

examples/save_restore.html

@@ -26,50 +26,35 @@ window.onload = function()
 
     var state;
 
-    document.getElementById("save_restore").onclick = function()
+    document.getElementById("save_restore").onclick = async function()
     {
         var button = this;
 
         if(state)
         {
             button.value = "Save state";
-
-            emulator.restore_state(state);
+            await emulator.restore_state(state);
             state = undefined;
         }
         else
         {
-            emulator.save_state(function(error, new_state)
-            {
-                if(error)
-                {
-                    throw error;
-                }
-
-                console.log("Saved state of " + new_state.byteLength + " bytes");
-                button.value = "Restore state";
-                state = new_state;
-            });
+            const new_state = await emulator.save_state();
+            console.log("Saved state of " + new_state.byteLength + " bytes");
+            button.value = "Restore state";
+            state = new_state;
         }
 
         button.blur();
     };
 
-    document.getElementById("save_file").onclick = function()
+    document.getElementById("save_file").onclick = async function()
     {
-        emulator.save_state(function(error, new_state)
-        {
-            if(error)
-            {
-                throw error;
-            }
-
-            var a = document.createElement("a");
-            a.download = "v86state.bin";
-            a.href = window.URL.createObjectURL(new Blob([new_state]));
-            a.dataset.downloadurl = "application/octet-stream:" + a.download + ":" + a.href;
-            a.click();
-        });
+        const new_state = await emulator.save_state();
+        var a = document.createElement("a");
+        a.download = "v86state.bin";
+        a.href = window.URL.createObjectURL(new Blob([new_state]));
+        a.dataset.downloadurl = "application/octet-stream:" + a.download + ":" + a.href;
+        a.click();
 
         this.blur();
     };
@@ -81,9 +66,9 @@ window.onload = function()
             var filereader = new FileReader();
             emulator.stop();
 
-            filereader.onload = function(e)
+            filereader.onload = async function(e)
             {
-                emulator.restore_state(e.target.result);
+                await emulator.restore_state(e.target.result);
                 emulator.run();
             };
 

src/browser/filestorage.js

@@ -99,10 +99,11 @@ ServerFileStorageWrapper.prototype.load_from_server = function(sha256sum)
 {
     return new Promise((resolve, reject) =>
     {
-        v86util.load_file(this.baseurl + sha256sum, { done: buffer =>
+        v86util.load_file(this.baseurl + sha256sum, { done: async buffer =>
         {
             const data = new Uint8Array(buffer);
-            this.cache(sha256sum, data).then(() => resolve(data));
+            await this.cache(sha256sum, data);
+            resolve(data);
         }});
     });
 };

src/browser/main.js

@@ -1575,20 +1575,10 @@
         //    $("memory_dump_dmp").blur();
         //};
 
-        $("save_state").onclick = function()
+        $("save_state").onclick = async function()
         {
-            emulator.save_state(function(error, result)
-            {
-                if(error)
-                {
-                    console.log(error.stack);
-                    console.log("Couldn't save state: ", error);
-                }
-                else
-                {
-                    dump_file(result, "v86state.bin");
-                }
-            });
+            const result = await emulator.save_state();
+            dump_file(result, "v86state.bin");
 
             $("save_state").blur();
         };
@@ -1599,7 +1589,7 @@
             $("load_state").blur();
         };
 
-        $("load_state_input").onchange = function()
+        $("load_state_input").onchange = async function()
         {
             var file = this.files[0];
 
@@ -1612,15 +1602,15 @@
 
             if(was_running)
             {
-                emulator.stop();
+                await emulator.stop();
             }
 
             var filereader = new FileReader();
-            filereader.onload = function(e)
+            filereader.onload = async function(e)
             {
                 try
                 {
-                    emulator.restore_state(e.target.result);
+                    await emulator.restore_state(e.target.result);
                 }
                 catch(err)
                 {
@@ -1789,9 +1779,9 @@
                 var loader = new v86util.SyncFileBuffer(file);
                 loader.onload = function()
                 {
-                    loader.get_buffer(function(buffer)
+                    loader.get_buffer(async function(buffer)
                     {
-                        emulator.create_file("/" + file.name, new Uint8Array(buffer));
+                        await emulator.create_file("/" + file.name, new Uint8Array(buffer));
                     });
                 };
                 loader.load();
@@ -1801,7 +1791,7 @@
             this.blur();
         };
 
-        $("filesystem_get_file").onkeypress = function(e)
+        $("filesystem_get_file").onkeypress = async function(e)
         {
             if(e.which !== 13)
             {
@@ -1810,23 +1800,30 @@
 
             this.disabled = true;
 
-            emulator.read_file(this.value, function(err, uint8array)
+            let result;
+            try
             {
-                this.disabled = false;
+                 result = await emulator.read_file(this.value);
+            }
+            catch(err)
+            {
+                console.log(err);
+            }
 
-                if(uint8array)
-                {
-                    var filename = this.value.replace(/\/$/, "").split("/");
-                    filename = filename[filename.length - 1] || "root";
+            this.disabled = false;
 
-                    dump_file(uint8array, filename);
-                    this.value = "";
-                }
-                else
-                {
-                    alert("Can't read file");
-                }
-            }.bind(this));
+            if(result)
+            {
+                var filename = this.value.replace(/\/$/, "").split("/");
+                filename = filename[filename.length - 1] || "root";
+
+                dump_file(result, filename);
+                this.value = "";
+            }
+            else
+            {
+                alert("Can't read file");
+            }
         };
     }
 

src/browser/starter.js

@@ -183,23 +183,22 @@ function V86Starter(options)
                 }
 
                 v86util.load_file(v86_bin, {
-                    done: bytes =>
+                    done: async bytes =>
                     {
-                        WebAssembly
-                            .instantiate(bytes, env)
-                            .then(({ instance }) => {
-                                resolve(instance.exports);
-                            }, err => {
-                                v86util.load_file(v86_bin_fallback, {
-                                    done: bytes => {
-                                        WebAssembly
-                                            .instantiate(bytes, env)
-                                            .then(({ instance }) => {
-                                                resolve(instance.exports);
-                                            });
+                        try
+                        {
+                            const { instance } = await WebAssembly.instantiate(bytes, env);
+                            resolve(instance.exports);
+                        }
+                        catch(err)
+                        {
+                            v86util.load_file(v86_bin_fallback, {
+                                    done: async bytes => {
+                                        const { instance } = await WebAssembly.instantiate(bytes, env);
+                                        resolve(instance.exports);
                                     },
                                 });
-                            });
+                        }
                     },
                     progress: e =>
                     {
@@ -586,7 +585,7 @@ V86Starter.prototype.continue_init = async function(emulator, options)
     }.bind(this);
     cont(0);
 
-    function done()
+    async function done()
     {
         //if(settings.initial_state)
         //{
@@ -607,18 +606,17 @@ V86Starter.prototype.continue_init = async function(emulator, options)
 
             if(options["bzimage_initrd_from_filesystem"])
             {
-                const { bzimage, initrd } = this.get_bzimage_initrd_from_filesystem(settings.fs9p);
+                const { bzimage_path, initrd_path } = this.get_bzimage_initrd_from_filesystem(settings.fs9p);
 
-                dbg_log("Found bzimage: " + bzimage + " and initrd: " + initrd);
+                dbg_log("Found bzimage: " + bzimage_path + " and initrd: " + initrd_path);
 
-                Promise.all([
-                    settings.fs9p.read_file(initrd),
-                    settings.fs9p.read_file(bzimage),
-                ]).then(([initrd, bzimage]) => {
-                    put_on_settings.call(this, "initrd", new SyncBuffer(initrd.buffer));
-                    put_on_settings.call(this, "bzimage", new SyncBuffer(bzimage.buffer));
-                    finish.call(this);
-                });
+                const [initrd, bzimage] = await Promise.all([
+                    settings.fs9p.read_file(initrd_path),
+                    settings.fs9p.read_file(bzimage_path),
+                ]);
+                put_on_settings.call(this, "initrd", new SyncBuffer(initrd.buffer));
+                put_on_settings.call(this, "bzimage", new SyncBuffer(bzimage.buffer));
+                finish.call(this);
             }
             else
             {
@@ -664,8 +662,8 @@ V86Starter.prototype.get_bzimage_initrd_from_filesystem = function(filesystem)
     const root = (filesystem.read_dir("/") || []).map(x => "/" + x);
     const boot = (filesystem.read_dir("/boot/") || []).map(x => "/boot/" + x);
 
-    let initrd;
-    let bzimage;
+    let initrd_path;
+    let bzimage_path;
 
     for(let f of [].concat(root, boot))
     {
@@ -673,25 +671,25 @@ V86Starter.prototype.get_bzimage_initrd_from_filesystem = function(filesystem)
         const is_bzimage = /vmlinuz/i.test(f) || /bzimage/i.test(f);
         const is_initrd = /initrd/i.test(f) || /initramfs/i.test(f);
 
-        if(is_bzimage && (!bzimage || !old))
+        if(is_bzimage && (!bzimage_path || !old))
         {
-            bzimage = f;
+            bzimage_path = f;
         }
 
-        if(is_initrd && (!initrd || !old))
+        if(is_initrd && (!initrd_path || !old))
         {
-            initrd = f;
+            initrd_path = f;
         }
     }
 
-    if(!initrd || !bzimage)
+    if(!initrd_path || !bzimage_path)
     {
         console.log("Failed to find bzimage or initrd in filesystem. Files:");
         console.log(root.join(" "));
         console.log(boot.join(" "));
     }
 
-    return { initrd, bzimage };
+    return { initrd_path, bzimage_path };
 };
 
 /**
@@ -699,7 +697,7 @@ V86Starter.prototype.get_bzimage_initrd_from_filesystem = function(filesystem)
  * asynchronous.
  * @export
  */
-V86Starter.prototype.run = function()
+V86Starter.prototype.run = async function()
 {
     this.bus.send("cpu-run");
 };
@@ -708,7 +706,7 @@ V86Starter.prototype.run = function()
  * Stop emulation. Do nothing if emulator is not running. Can be asynchronous.
  * @export
  */
-V86Starter.prototype.stop = function()
+V86Starter.prototype.stop = async function()
 {
     this.bus.send("cpu-stop");
 };
@@ -780,34 +778,22 @@ V86Starter.prototype.remove_listener = function(event, listener)
  * @param {ArrayBuffer} state
  * @export
  */
-V86Starter.prototype.restore_state = function(state)
+V86Starter.prototype.restore_state = async function(state)
 {
+    console.assert(arguments.length === 1);
     this.v86.restore_state(state);
 };
 
 /**
- * Asynchronously save the current state of the emulator. The first argument to
- * the callback is an Error object if something went wrong and is null
- * otherwise.
+ * Asynchronously save the current state of the emulator.
  *
- * @param {function(Object, ArrayBuffer)} callback
+ * @return {Promise<ArrayBuffer>}
  * @export
  */
-V86Starter.prototype.save_state = function(callback)
+V86Starter.prototype.save_state = async function()
 {
-    // Might become asynchronous at some point
-
-    setTimeout(function()
-    {
-        try
-        {
-            callback(null, this.v86.save_state());
-        }
-        catch(e)
-        {
-            callback(e, null);
-        }
-    }.bind(this), 0);
+    console.assert(arguments.length === 0);
+    return this.v86.save_state();
 };
 
 /**
@@ -1169,18 +1155,15 @@ V86Starter.prototype.mount_fs = async function(path, baseurl, basefs, callback)
 
 /**
  * Write to a file in the 9p filesystem. Nothing happens if no filesystem has
- * been initialized. First argument to the callback is an error object if
- * something went wrong and null otherwise.
+ * been initialized.
  *
  * @param {string} file
  * @param {Uint8Array} data
- * @param {function(Object)=} callback
  * @export
  */
-V86Starter.prototype.create_file = function(file, data, callback)
+V86Starter.prototype.create_file = async function(file, data)
 {
-    callback = callback || function() {};
-
+    console.assert(arguments.length === 2);
     var fs = this.fs9p;
 
     if(!fs)
@@ -1197,15 +1180,11 @@ V86Starter.prototype.create_file = function(file, data, callback)
 
     if(!not_found)
     {
-        fs.CreateBinaryFile(filename, parent_id, data)
-            .then(() => callback(null));
+        await fs.CreateBinaryFile(filename, parent_id, data);
     }
     else
     {
-        setTimeout(function()
-        {
-            callback(new FileNotFoundError());
-        }, 0);
+        return Promise.reject(new FileNotFoundError());
     }
 };
 
@@ -1214,11 +1193,11 @@ V86Starter.prototype.create_file = function(file, data, callback)
  * initialized.
  *
  * @param {string} file
- * @param {function(Object, Uint8Array)} callback
  * @export
  */
-V86Starter.prototype.read_file = function(file, callback)
+V86Starter.prototype.read_file = async function(file)
 {
+    console.assert(arguments.length === 1);
     var fs = this.fs9p;
 
     if(!fs)
@@ -1226,16 +1205,16 @@ V86Starter.prototype.read_file = function(file, callback)
         return;
     }
 
-    fs.read_file(file).then((result) => {
-        if(result)
-        {
-            callback(null, result);
-        }
-        else
-        {
-            callback(new FileNotFoundError(), null);
-        }
-    });
+    const result = await fs.read_file(file);
+
+    if(result)
+    {
+        return result;
+    }
+    else
+    {
+        return Promise.reject(new FileNotFoundError());
+    }
 };
 
 V86Starter.prototype.automatically = function(steps)

tests/api/state.js

@@ -45,30 +45,23 @@ function run_test(name, config, done)
 {
     const emulator = new V86(config);
 
-    setTimeout(function()
+    setTimeout(async function()
         {
             console.log("Saving: %s", name);
-            emulator.save_state(function(error, state)
+            const state = await emulator.save_state();
+
+            setTimeout(async function()
                 {
-                    if(error)
-                    {
-                        console.error(error);
-                        assert(false);
-                    }
+                    console.log("Restoring: %s", name);
+                    await emulator.restore_state(state);
 
                     setTimeout(function()
                         {
-                            console.log("Restoring: %s", name);
-                            emulator.restore_state(state);
-
-                            setTimeout(function()
-                                {
-                                    console.log("Done: %s", name);
-                                    emulator.stop();
-                                    done && done();
-                                }, 1000);
+                            console.log("Done: %s", name);
+                            emulator.stop();
+                            done && done();
                         }, 1000);
-                });
+                }, 1000);
         }, 5000);
 }
 

tests/devices/virtio_9p.js

@@ -142,20 +142,11 @@ const tests =
         },
         capture_trigger: "start-capture",
         end_trigger: "done-read-existing",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
-            emulator.read_file("read-existing", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading read-existing failed: %s",  err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(capture, Buffer.from(data).toString());
-                done();
-            });
+            const data = await emulator.read_file("read-existing");
+            assert_equal(capture, Buffer.from(data).toString());
+            done();
         },
     },
     {
@@ -167,25 +158,16 @@ const tests =
             emulator.serial0_send("echo done-read-new\n");
         },
         end_trigger: "done-read-new",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
-            emulator.read_file("read-new", function(err, data)
+            const data = await emulator.read_file("read-new");
+            assert_equal(data.length, 512 * 1024);
+            if(data.find(v => v !== 0))
             {
-                if(err)
-                {
-                    log_warn("Reading read-new failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(data.length, 512 * 1024);
-                if(data.find(v => v !== 0))
-                {
-                    log_warn("Fail: Incorrect data. Expected all zeros.");
-                    test_fail();
-                }
-                done();
-            });
+                log_warn("Fail: Incorrect data. Expected all zeros.");
+                test_fail();
+            }
+            done();
         },
     },
     {
@@ -203,21 +185,12 @@ const tests =
         },
         capture_trigger: "start-capture",
         end_trigger: "done-read-async",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
             assert_equal(capture, "bar\n");
-            emulator.read_file("foo", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading foo failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(Buffer.from(data).toString(), "bar\n");
-                done();
-            });
+            const data = await emulator.read_file("foo");
+            assert_equal(Buffer.from(data).toString(), "bar\n");
+            done();
         },
     },
     {
@@ -579,20 +552,11 @@ const tests =
             emulator.serial0_send("echo fifomessage > /mnt/testfifo\n");
         },
         end_trigger: "done-fifo",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
-            emulator.read_file("testfifo-output", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading testfifo-output failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(Buffer.from(data).toString(), "fifomessage\n");
-                done();
-            });
+            const data = await emulator.read_file("testfifo-output");
+            assert_equal(Buffer.from(data).toString(), "fifomessage\n");
+            done();
         },
     },
     {
@@ -628,20 +592,11 @@ const tests =
             emulator.serial0_send("echo done-mkdir\n");
         },
         end_trigger: "done-mkdir",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
-            emulator.read_file("a-dir/e-file", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading a-dir/e-file failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(Buffer.from(data).toString(), "mkdirfoobar\n");
-                done();
-            });
+            const data = await emulator.read_file("a-dir/e-file");
+            assert_equal(Buffer.from(data).toString(), "mkdirfoobar\n");
+            done();
         },
     },
     {
@@ -1251,21 +1206,12 @@ const tests =
         },
         capture_trigger: "start-capture",
         end_trigger: "done-read-mounted",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
             assert_equal(capture, "bar\nfoobaz\n");
-            emulator.read_file("/a/b/fs2/dir/bar", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading /a/b/fs2/dir/bar failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(Buffer.from(data).toString(), "foobaz\n");
-                done();
-            });
+            const data = await emulator.read_file("/a/b/fs2/dir/bar");
+            assert_equal(Buffer.from(data).toString(), "foobaz\n");
+            done();
         },
     },
     {
@@ -1294,7 +1240,7 @@ const tests =
         },
         capture_trigger: "start-capture",
         end_trigger: "done-write-mounted",
-        end: (capture, done) =>
+        end: async (capture, done) =>
         {
             const lines = capture.split("\n");
             assert_equal(lines.shift(), "foobar");
@@ -1304,18 +1250,9 @@ const tests =
                 assert_equal(line, test_file_string.slice(pos, line.length));
                 pos += line.length;
             }
-            emulator.read_file("a/b/fs2/c/write-new-guest", function(err, data)
-            {
-                if(err)
-                {
-                    log_warn("Reading a/b/fs2/c/write-new-guest failed: %s", err);
-                    test_fail();
-                    done();
-                    return;
-                }
-                assert_equal(Buffer.from(data).toString(), "foobar\n");
-                done();
-            });
+            const data = await emulator.read_file("a/b/fs2/c/write-new-guest");
+            assert_equal(Buffer.from(data).toString(), "foobar\n");
+            done();
         },
     },
     {
@@ -1717,7 +1654,7 @@ function do_mounts()
     }
 }
 
-function load_files()
+async function load_files()
 {
     console.log("    Loading additional files");
     if(tests[test_num].files)
@@ -1725,27 +1662,20 @@ function load_files()
         let remaining = tests[test_num].files.length;
         for(const f of tests[test_num].files)
         {
-            emulator.create_file(f.file, f.data, function(err)
+            await emulator.create_file(f.file, f.data);
+
+            remaining--;
+            if(!remaining)
             {
-                if(err)
+                if(test_has_failed)
                 {
-                    log_warn("Failed to add file required for test %s: %s",
-                        tests[test_num].name, err);
-                    test_fail();
+                    report_test();
                 }
-                remaining--;
-                if(!remaining)
+                else
                 {
-                    if(test_has_failed)
-                    {
-                        report_test();
-                    }
-                    else
-                    {
-                        start_test();
-                    }
+                    start_test();
                 }
-            });
+            }
         }
     }
     else

tests/jit-paging/run.js

@@ -29,7 +29,7 @@ emulator.bus.register("emulator-started", function()
 var ran_command = false;
 var line = "";
 
-emulator.add_listener("serial0-output-char", function(chr)
+emulator.add_listener("serial0-output-char", async function(chr)
 {
     if(chr < " " && chr !== "\n" && chr !== "\t" || chr > "~")
     {
@@ -59,21 +59,19 @@ emulator.add_listener("serial0-output-char", function(chr)
     {
         console.error("Done. Reading result ...");
 
-        emulator.read_file("/result", function(err, data)
-            {
-                emulator.stop();
-                if(err) throw err;
-                let result = Buffer.from(data).toString();
-                if(result !== "test_shared passed\ntest_consecutive_written passed\n")
-                {
-                    console.error("[!] Error. Result was:\n" + result);
-                    process.exit(1);
-                }
-                else
-                {
-                    console.log("[+] Test passed");
-                }
-            });
-    }
+        const data = await emulator.read_file("/result");
+
+        emulator.stop();
 
+        let result = Buffer.from(data).toString();
+        if(result !== "test_shared passed\ntest_consecutive_written passed\n")
+        {
+            console.error("[!] Error. Result was:\n" + result);
+            process.exit(1);
+        }
+        else
+        {
+            console.log("[+] Test passed");
+        }
+    }
 });

tests/qemu/run.js

@@ -29,7 +29,7 @@ emulator.bus.register("emulator-started", function()
 var ran_command = false;
 var line = "";
 
-emulator.add_listener("serial0-output-char", function(chr)
+emulator.add_listener("serial0-output-char", async function(chr)
 {
     if(chr < " " && chr !== "\n" && chr !== "\t" || chr > "~")
     {
@@ -59,17 +59,10 @@ emulator.add_listener("serial0-output-char", function(chr)
     {
         console.error("Done. Reading result ...");
 
-        emulator.read_file("/result", function(err, data)
-            {
-                if(err)
-                {
-                    console.error("Reading test result failed: " + err);
-                    process.exit(1);
-                }
-                console.error("Got result, writing to stdout");
-                process.stdout.write(Buffer.from(data));
-                emulator.stop();
-            });
-    }
+        const data = await emulator.read_file("/result");
+        console.error("Got result, writing to stdout");
 
+        process.stdout.write(Buffer.from(data));
+        emulator.stop();
+    }
 });

tools/docker/debian/build-state.js

@@ -58,21 +58,15 @@ emulator.add_listener("serial0-output-char", function(c)
         // sync and drop caches: Makes it safer to change the filesystem as fewer files are rendered
         emulator.serial0_send("sync;echo 3 >/proc/sys/vm/drop_caches\n");
 
-        setTimeout(function ()
+        setTimeout(async function ()
             {
-                emulator.save_state(function(err, s)
+                const s = await emulator.save_state();
+
+                fs.writeFile(OUTPUT_FILE, new Uint8Array(s), function(e)
                     {
-                        if(err)
-                        {
-                            throw err;
-                        }
-
-                        fs.writeFile(OUTPUT_FILE, new Uint8Array(s), function(e)
-                            {
-                                if(e) throw e;
-                                console.error("Saved as " + OUTPUT_FILE);
-                                stop();
-                            });
+                        if(e) throw e;
+                        console.error("Saved as " + OUTPUT_FILE);
+                        stop();
                     });
             }, 10 * 1000);
     }