snap

package.json

@@ -8,6 +8,7 @@
  "serve-demo": "cd src/demo && ../../node_modules/.bin/webpack serve "
  },
  "dependencies": {
+ "detect-browser": "^5.2.0",
  "sql.js": "file:/Users/james/projects/sql.js",
  "uuid": "^8.3.2"
  },

src/backend-indexeddb.js

@@ -15,8 +15,23 @@ function positionToKey(pos, blockSize) {
 }
 
 function invokeWorker(method, args) {
- // console.log('invoking', method, args);
  switch (method) {
+ case 'stats-start': {
+ writer.string('stats-start');
+ writer.finalize();
+ reader.int32();
+ reader.done();
+ break;
+ }
+
+ case 'stats': {
+ writer.string('stats');
+ writer.finalize();
+ reader.int32();
+ reader.done();
+ break;
+ }
+
  case 'readBlocks': {
  let { name, positions, blockSize } = args;
 
@@ -29,7 +44,12 @@ function invokeWorker(method, args) {
 
  let data = reader.bytes();
  reader.done();
- res.push({ pos, data });
+ res.push({
+ pos,
+ // If th length is 0, the block didn't exist. We return a
+ // blank block in that case
+ data: data.byteLength === 0 ? new ArrayBuffer(blockSize) : data
+ });
  }
 
  return res;
@@ -89,6 +109,7 @@ function invokeWorker(method, args) {
  case 'lockFile': {
  writer.string('lockFile');
  writer.string(args.name);
+ writer.int32(args.lockType);
  writer.finalize();
 
  let res = reader.int32();
@@ -99,11 +120,12 @@ function invokeWorker(method, args) {
  case 'unlockFile': {
  writer.string('unlockFile');
  writer.string(args.name);
+ writer.int32(args.lockType);
  writer.finalize();
 
  let res = reader.int32();
  reader.done();
- return res;
+ return res === 0;
  }
  }
 }
@@ -114,29 +136,24 @@ class FileOps {
  }
 
  startStats() {
- this.stats = {
- read: 0,
- write: 0
- };
+ return invokeWorker('stats-start');
  }
 
- endStats() {
- let stats = this.stats;
- this.stats = {};
- return stats;
+ stats() {
+ return invokeWorker('stats');
  }
 
  getStoreName() {
  // TODO: better sanitization
  return this.filename.replace(/\//g, '-');
  }
 
- lock() {
- return invokeWorker('lockFile', { name: this.getStoreName() });
+ lock(lockType) {
+ return invokeWorker('lockFile', { name: this.getStoreName(), lockType });
  }
 
- unlock() {
- return invokeWorker('unlockFile', { name: this.getStoreName() });
+ unlock(lockType) {
+ return invokeWorker('unlockFile', { name: this.getStoreName(), lockType });
  }
 
  delete() {
@@ -152,9 +169,9 @@ class FileOps {
  }
 
  readBlocks(positions, blockSize) {
- if (Math.random() < 0.005) {
- console.log('reading', positions);
- }
+ // if (Math.random() < 0.005) {
+ //  console.log('reading', positions);
+ // }
 
  if (this.stats) {
  this.stats.read += positions.length;

src/blockedfs.js

@@ -1,5 +1,3 @@
-const SQLITE_NOTFOUND = 12;
-
 const ERRNO_CODES = {
  EPERM: 63,
  ENOENT: 44,
@@ -166,12 +164,7 @@ export default class BlockedFS {
  },
  mknod: (parent, name, mode, dev) => {
  if (name.endsWith('.lock')) {
- let file = this.FS.lookupNode(parent, name.replace(/\.lock$/, ''));
-
- if (!file.contents.lock()) {
- // File exists (can't lock)
- throw new this.FS.ErrnoError(20);
- }
+ throw new Error('Locking via lockfiles is not supported')
  }
 
  return this.createNode(parent, name, mode, dev);
@@ -183,12 +176,6 @@ export default class BlockedFS {
  let node = this.FS.lookupNode(parent, name);
  node.contents.delete(name);
  },
- rmdir: (parent, name) => {
- if (name.endsWith('.lock')) {
- let file = this.FS.lookupNode(parent, name.replace(/\.lock$/, ''));
- file.contents.unlock();
- }
- },
  readdir: node => {
  // We could list all the available databases here if `node` is
  // the root directory. However Firefox does not implemented
@@ -220,7 +207,7 @@ export default class BlockedFS {
  },
 
  read: (stream, buffer, offset, length, position) => {
- // console.log('read', offset, length, position);
+ console.log('read', offset, length, position);
  return stream.node.contents.read(buffer, offset, length, position);
  },
 
@@ -267,6 +254,17 @@ export default class BlockedFS {
  return this.createNode(null, '/', 16384 /* dir */ | 511 /* 0777 */, 0);
  }
 
+ lock(path, lockType) {
+ console.log('locking', path, lockType)
+ let { node } = this.FS.lookupPath(path)
+ return node.contents.lock(lockType)
+ }
+
+ unlock(path, lockType) {
+ let { node } = this.FS.lookupPath(path)
+ return node.contents.unlock(lockType)
+ }
+
  // TODO: implement lookup for existing files (maybe)
 
  createNode(parent, name, mode, dev) {
@@ -282,7 +280,6 @@ export default class BlockedFS {
  lookup: this.node_ops.lookup,
  unlink: this.node_ops.unlink,
  setattr: this.node_ops.setattr,
- rmdir: this.node_ops.rmdir
  };
  node.stream_ops = {};
  node.contents = {};