Bugfix: fix race conditions

dist/utils/sync.js

@@ -15,10 +15,66 @@ Object.defineProperty(exports, "__esModule", { value: true });
 exports.default = sync;
 const fs_1 = __importDefault(require("fs"));
 const path_1 = __importDefault(require("path"));
+const os_1 = __importDefault(require("os"));
 const util_1 = __importDefault(require("util"));
+const crypto_1 = __importDefault(require("crypto"));
 const child_process_1 = require("child_process");
 const grab_dir_names_1 = __importDefault(require("./grab-dir-names"));
+const grab_folders_files_string_paths_1 = require("./grab-folders-files-string-paths");
+const delay_1 = __importDefault(require("./delay"));
 const execPromise = util_1.default.promisify(child_process_1.exec);
+const LOCK_STALE_MS = 5 * 60 * 1000;
+const LOCK_RETRY_MS = 100;
+function lockPathFor(dirPath) {
+    const hash = crypto_1.default
+        .createHash("sha1")
+        .update(path_1.default.resolve(dirPath))
+        .digest("hex")
+        .slice(0, 16);
+    return path_1.default.join(os_1.default.tmpdir(), `turbosync-${hash}.lock`);
+}
+function acquireLock(lockPath) {
+    return __awaiter(this, void 0, void 0, function* () {
+        while (true) {
+            try {
+                const fd = fs_1.default.openSync(lockPath, "wx");
+                fs_1.default.writeFileSync(fd, String(process.pid));
+                fs_1.default.closeSync(fd);
+                return;
+            }
+            catch (error) {
+                if (error.code !== "EEXIST")
+                    throw error;
+                try {
+                    const { mtimeMs } = fs_1.default.statSync(lockPath);
+                    if (Date.now() - mtimeMs > LOCK_STALE_MS) {
+                        fs_1.default.unlinkSync(lockPath);
+                        continue;
+                    }
+                }
+                catch (_a) {
+                    continue;
+                }
+                yield (0, delay_1.default)(LOCK_RETRY_MS);
+            }
+        }
+    });
+}
+function acquireLocks(lockPaths) {
+    return __awaiter(this, void 0, void 0, function* () {
+        for (const lockPath of lockPaths) {
+            yield acquireLock(lockPath);
+        }
+    });
+}
+function releaseLocks(lockPaths) {
+    for (const lockPath of lockPaths) {
+        try {
+            fs_1.default.unlinkSync(lockPath);
+        }
+        catch (_a) { }
+    }
+}
 function sync(_a) {
     return __awaiter(this, arguments, void 0, function* ({ options, dirs, dirPath, isFiles, firstRun, }) {
         var _b, _c;
@@ -78,9 +134,19 @@ function sync(_a) {
             }
             allCommandsArr.push(cmdArray);
         }
-        yield Promise.all(allCommandsArr.map((cmdArr) => {
-            return execPromise(cmdArr.join(" "));
-        }));
+        const lockPaths = [dirPath, ...dstDirs.map((dr) => (0, grab_folders_files_string_paths_1.fldFileToStr)(dr))]
+            .filter((pth) => Boolean(pth))
+            .map((pth) => lockPathFor(pth))
+            .sort();
+        yield acquireLocks(lockPaths);
+        try {
+            yield Promise.all(allCommandsArr.map((cmdArr) => {
+                return execPromise(cmdArr.join(" "));
+            }));
+        }
+        finally {
+            releaseLocks(lockPaths);
+        }
         console.log(`${dirPath} Folder Sync Complete. Exiting ...`);
     });
 }