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Diffstat (limited to 'ext/wasm/api/sqlite3-api-opfs.js')
-rw-r--r-- | ext/wasm/api/sqlite3-api-opfs.js | 1311 |
1 files changed, 1311 insertions, 0 deletions
diff --git a/ext/wasm/api/sqlite3-api-opfs.js b/ext/wasm/api/sqlite3-api-opfs.js new file mode 100644 index 0000000..da5496f --- /dev/null +++ b/ext/wasm/api/sqlite3-api-opfs.js @@ -0,0 +1,1311 @@ +/* + 2022-09-18 + + The author disclaims copyright to this source code. In place of a + legal notice, here is a blessing: + + * May you do good and not evil. + * May you find forgiveness for yourself and forgive others. + * May you share freely, never taking more than you give. + + *********************************************************************** + + This file holds the synchronous half of an sqlite3_vfs + implementation which proxies, in a synchronous fashion, the + asynchronous Origin-Private FileSystem (OPFS) APIs using a second + Worker, implemented in sqlite3-opfs-async-proxy.js. This file is + intended to be appended to the main sqlite3 JS deliverable somewhere + after sqlite3-api-oo1.js and before sqlite3-api-cleanup.js. +*/ +'use strict'; +self.sqlite3ApiBootstrap.initializers.push(function(sqlite3){ +/** + installOpfsVfs() returns a Promise which, on success, installs an + sqlite3_vfs named "opfs", suitable for use with all sqlite3 APIs + which accept a VFS. It is intended to be called via + sqlite3ApiBootstrap.initializersAsync or an equivalent mechanism. + + The installed VFS uses the Origin-Private FileSystem API for + all file storage. On error it is rejected with an exception + explaining the problem. Reasons for rejection include, but are + not limited to: + + - The counterpart Worker (see below) could not be loaded. + + - The environment does not support OPFS. That includes when + this function is called from the main window thread. + + Significant notes and limitations: + + - As of this writing, OPFS is still very much in flux and only + available in bleeding-edge versions of Chrome (v102+, noting that + that number will increase as the OPFS API matures). + + - The OPFS features used here are only available in dedicated Worker + threads. This file tries to detect that case, resulting in a + rejected Promise if those features do not seem to be available. + + - It requires the SharedArrayBuffer and Atomics classes, and the + former is only available if the HTTP server emits the so-called + COOP and COEP response headers. These features are required for + proxying OPFS's synchronous API via the synchronous interface + required by the sqlite3_vfs API. + + - This function may only be called a single time. When called, this + function removes itself from the sqlite3 object. + + All arguments to this function are for internal/development purposes + only. They do not constitute a public API and may change at any + time. + + The argument may optionally be a plain object with the following + configuration options: + + - proxyUri: as described above + + - verbose (=2): an integer 0-3. 0 disables all logging, 1 enables + logging of errors. 2 enables logging of warnings and errors. 3 + additionally enables debugging info. + + - sanityChecks (=false): if true, some basic sanity tests are + run on the OPFS VFS API after it's initialized, before the + returned Promise resolves. + + On success, the Promise resolves to the top-most sqlite3 namespace + object and that object gets a new object installed in its + `opfs` property, containing several OPFS-specific utilities. +*/ +const installOpfsVfs = function callee(options){ + if(!self.SharedArrayBuffer || + !self.Atomics || + !self.FileSystemHandle || + !self.FileSystemDirectoryHandle || + !self.FileSystemFileHandle || + !self.FileSystemFileHandle.prototype.createSyncAccessHandle || + !navigator.storage.getDirectory){ + return Promise.reject( + new Error("This environment does not have OPFS support.") + ); + } + if(!options || 'object'!==typeof options){ + options = Object.create(null); + } + const urlParams = new URL(self.location.href).searchParams; + if(undefined===options.verbose){ + options.verbose = urlParams.has('opfs-verbose') ? 3 : 2; + } + if(undefined===options.sanityChecks){ + options.sanityChecks = urlParams.has('opfs-sanity-check'); + } + if(undefined===options.proxyUri){ + options.proxyUri = callee.defaultProxyUri; + } + + if('function' === typeof options.proxyUri){ + options.proxyUri = options.proxyUri(); + } + const thePromise = new Promise(function(promiseResolve, promiseReject_){ + const loggers = { + 0:console.error.bind(console), + 1:console.warn.bind(console), + 2:console.log.bind(console) + }; + const logImpl = (level,...args)=>{ + if(options.verbose>level) loggers[level]("OPFS syncer:",...args); + }; + const log = (...args)=>logImpl(2, ...args); + const warn = (...args)=>logImpl(1, ...args); + const error = (...args)=>logImpl(0, ...args); + const toss = function(...args){throw new Error(args.join(' '))}; + const capi = sqlite3.capi; + const wasm = sqlite3.wasm; + const sqlite3_vfs = capi.sqlite3_vfs; + const sqlite3_file = capi.sqlite3_file; + const sqlite3_io_methods = capi.sqlite3_io_methods; + /** + Generic utilities for working with OPFS. This will get filled out + by the Promise setup and, on success, installed as sqlite3.opfs. + */ + const opfsUtil = Object.create(null); + /** + Not part of the public API. Solely for internal/development + use. + */ + opfsUtil.metrics = { + dump: function(){ + let k, n = 0, t = 0, w = 0; + for(k in state.opIds){ + const m = metrics[k]; + n += m.count; + t += m.time; + w += m.wait; + m.avgTime = (m.count && m.time) ? (m.time / m.count) : 0; + m.avgWait = (m.count && m.wait) ? (m.wait / m.count) : 0; + } + console.log(self.location.href, + "metrics for",self.location.href,":",metrics, + "\nTotal of",n,"op(s) for",t, + "ms (incl. "+w+" ms of waiting on the async side)"); + console.log("Serialization metrics:",metrics.s11n); + W.postMessage({type:'opfs-async-metrics'}); + }, + reset: function(){ + let k; + const r = (m)=>(m.count = m.time = m.wait = 0); + for(k in state.opIds){ + r(metrics[k] = Object.create(null)); + } + let s = metrics.s11n = Object.create(null); + s = s.serialize = Object.create(null); + s.count = s.time = 0; + s = metrics.s11n.deserialize = Object.create(null); + s.count = s.time = 0; + } + }/*metrics*/; + const promiseReject = function(err){ + opfsVfs.dispose(); + return promiseReject_(err); + }; + const W = new Worker(options.proxyUri); + W._originalOnError = W.onerror /* will be restored later */; + W.onerror = function(err){ + // The error object doesn't contain any useful info when the + // failure is, e.g., that the remote script is 404. + error("Error initializing OPFS asyncer:",err); + promiseReject(new Error("Loading OPFS async Worker failed for unknown reasons.")); + }; + const pDVfs = capi.sqlite3_vfs_find(null)/*pointer to default VFS*/; + const dVfs = pDVfs + ? new sqlite3_vfs(pDVfs) + : null /* dVfs will be null when sqlite3 is built with + SQLITE_OS_OTHER. Though we cannot currently handle + that case, the hope is to eventually be able to. */; + const opfsVfs = new sqlite3_vfs(); + const opfsIoMethods = new sqlite3_io_methods(); + opfsVfs.$iVersion = 2/*yes, two*/; + opfsVfs.$szOsFile = capi.sqlite3_file.structInfo.sizeof; + opfsVfs.$mxPathname = 1024/*sure, why not?*/; + opfsVfs.$zName = wasm.allocCString("opfs"); + // All C-side memory of opfsVfs is zeroed out, but just to be explicit: + opfsVfs.$xDlOpen = opfsVfs.$xDlError = opfsVfs.$xDlSym = opfsVfs.$xDlClose = null; + opfsVfs.ondispose = [ + '$zName', opfsVfs.$zName, + 'cleanup default VFS wrapper', ()=>(dVfs ? dVfs.dispose() : null), + 'cleanup opfsIoMethods', ()=>opfsIoMethods.dispose() + ]; + /** + Pedantic sidebar about opfsVfs.ondispose: the entries in that array + are items to clean up when opfsVfs.dispose() is called, but in this + environment it will never be called. The VFS instance simply + hangs around until the WASM module instance is cleaned up. We + "could" _hypothetically_ clean it up by "importing" an + sqlite3_os_end() impl into the wasm build, but the shutdown order + of the wasm engine and the JS one are undefined so there is no + guaranty that the opfsVfs instance would be available in one + environment or the other when sqlite3_os_end() is called (_if_ it + gets called at all in a wasm build, which is undefined). + */ + /** + State which we send to the async-api Worker or share with it. + This object must initially contain only cloneable or sharable + objects. After the worker's "inited" message arrives, other types + of data may be added to it. + + For purposes of Atomics.wait() and Atomics.notify(), we use a + SharedArrayBuffer with one slot reserved for each of the API + proxy's methods. The sync side of the API uses Atomics.wait() + on the corresponding slot and the async side uses + Atomics.notify() on that slot. + + The approach of using a single SAB to serialize comms for all + instances might(?) lead to deadlock situations in multi-db + cases. We should probably have one SAB here with a single slot + for locking a per-file initialization step and then allocate a + separate SAB like the above one for each file. That will + require a bit of acrobatics but should be feasible. The most + problematic part is that xOpen() would have to use + postMessage() to communicate its SharedArrayBuffer, and mixing + that approach with Atomics.wait/notify() gets a bit messy. + */ + const state = Object.create(null); + state.verbose = options.verbose; + state.littleEndian = (()=>{ + const buffer = new ArrayBuffer(2); + new DataView(buffer).setInt16(0, 256, true /* ==>littleEndian */); + // Int16Array uses the platform's endianness. + return new Int16Array(buffer)[0] === 256; + })(); + /** + Whether the async counterpart should log exceptions to + the serialization channel. That produces a great deal of + noise for seemingly innocuous things like xAccess() checks + for missing files, so this option may have one of 3 values: + + 0 = no exception logging + + 1 = only log exceptions for "significant" ops like xOpen(), + xRead(), and xWrite(). + + 2 = log all exceptions. + */ + state.asyncS11nExceptions = 1; + /* Size of file I/O buffer block. 64k = max sqlite3 page size, and + xRead/xWrite() will never deal in blocks larger than that. */ + state.fileBufferSize = 1024 * 64; + state.sabS11nOffset = state.fileBufferSize; + /** + The size of the block in our SAB for serializing arguments and + result values. Needs to be large enough to hold serialized + values of any of the proxied APIs. Filenames are the largest + part but are limited to opfsVfs.$mxPathname bytes. + */ + state.sabS11nSize = opfsVfs.$mxPathname * 2; + /** + The SAB used for all data I/O between the synchronous and + async halves (file i/o and arg/result s11n). + */ + state.sabIO = new SharedArrayBuffer( + state.fileBufferSize/* file i/o block */ + + state.sabS11nSize/* argument/result serialization block */ + ); + state.opIds = Object.create(null); + const metrics = Object.create(null); + { + /* Indexes for use in our SharedArrayBuffer... */ + let i = 0; + /* SAB slot used to communicate which operation is desired + between both workers. This worker writes to it and the other + listens for changes. */ + state.opIds.whichOp = i++; + /* Slot for storing return values. This worker listens to that + slot and the other worker writes to it. */ + state.opIds.rc = i++; + /* Each function gets an ID which this worker writes to + the whichOp slot. The async-api worker uses Atomic.wait() + on the whichOp slot to figure out which operation to run + next. */ + state.opIds.xAccess = i++; + state.opIds.xClose = i++; + state.opIds.xDelete = i++; + state.opIds.xDeleteNoWait = i++; + state.opIds.xFileControl = i++; + state.opIds.xFileSize = i++; + state.opIds.xLock = i++; + state.opIds.xOpen = i++; + state.opIds.xRead = i++; + state.opIds.xSleep = i++; + state.opIds.xSync = i++; + state.opIds.xTruncate = i++; + state.opIds.xUnlock = i++; + state.opIds.xWrite = i++; + state.opIds.mkdir = i++; + state.opIds['opfs-async-metrics'] = i++; + state.opIds['opfs-async-shutdown'] = i++; + /* The retry slot is used by the async part for wait-and-retry + semantics. Though we could hypothetically use the xSleep slot + for that, doing so might lead to undesired side effects. */ + state.opIds.retry = i++; + state.sabOP = new SharedArrayBuffer( + i * 4/* ==sizeof int32, noting that Atomics.wait() and friends + can only function on Int32Array views of an SAB. */); + opfsUtil.metrics.reset(); + } + /** + SQLITE_xxx constants to export to the async worker + counterpart... + */ + state.sq3Codes = Object.create(null); + [ + 'SQLITE_ACCESS_EXISTS', + 'SQLITE_ACCESS_READWRITE', + 'SQLITE_ERROR', + 'SQLITE_IOERR', + 'SQLITE_IOERR_ACCESS', + 'SQLITE_IOERR_CLOSE', + 'SQLITE_IOERR_DELETE', + 'SQLITE_IOERR_FSYNC', + 'SQLITE_IOERR_LOCK', + 'SQLITE_IOERR_READ', + 'SQLITE_IOERR_SHORT_READ', + 'SQLITE_IOERR_TRUNCATE', + 'SQLITE_IOERR_UNLOCK', + 'SQLITE_IOERR_WRITE', + 'SQLITE_LOCK_EXCLUSIVE', + 'SQLITE_LOCK_NONE', + 'SQLITE_LOCK_PENDING', + 'SQLITE_LOCK_RESERVED', + 'SQLITE_LOCK_SHARED', + 'SQLITE_MISUSE', + 'SQLITE_NOTFOUND', + 'SQLITE_OPEN_CREATE', + 'SQLITE_OPEN_DELETEONCLOSE', + 'SQLITE_OPEN_READONLY' + ].forEach((k)=>{ + if(undefined === (state.sq3Codes[k] = capi[k])){ + toss("Maintenance required: not found:",k); + } + }); + + /** + Runs the given operation (by name) in the async worker + counterpart, waits for its response, and returns the result + which the async worker writes to SAB[state.opIds.rc]. The + 2nd and subsequent arguments must be the aruguments for the + async op. + */ + const opRun = (op,...args)=>{ + const opNdx = state.opIds[op] || toss("Invalid op ID:",op); + state.s11n.serialize(...args); + Atomics.store(state.sabOPView, state.opIds.rc, -1); + Atomics.store(state.sabOPView, state.opIds.whichOp, opNdx); + Atomics.notify(state.sabOPView, state.opIds.whichOp) + /* async thread will take over here */; + const t = performance.now(); + Atomics.wait(state.sabOPView, state.opIds.rc, -1) + /* When this wait() call returns, the async half will have + completed the operation and reported its results. */; + const rc = Atomics.load(state.sabOPView, state.opIds.rc); + metrics[op].wait += performance.now() - t; + if(rc && state.asyncS11nExceptions){ + const err = state.s11n.deserialize(); + if(err) error(op+"() async error:",...err); + } + return rc; + }; + + /** + Not part of the public API. Only for test/development use. + */ + opfsUtil.debug = { + asyncShutdown: ()=>{ + warn("Shutting down OPFS async listener. The OPFS VFS will no longer work."); + opRun('opfs-async-shutdown'); + }, + asyncRestart: ()=>{ + warn("Attempting to restart OPFS VFS async listener. Might work, might not."); + W.postMessage({type: 'opfs-async-restart'}); + } + }; + + const initS11n = ()=>{ + /** + !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + ACHTUNG: this code is 100% duplicated in the other half of + this proxy! The documentation is maintained in the + "synchronous half". + !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + This proxy de/serializes cross-thread function arguments and + output-pointer values via the state.sabIO SharedArrayBuffer, + using the region defined by (state.sabS11nOffset, + state.sabS11nOffset]. Only one dataset is recorded at a time. + + This is not a general-purpose format. It only supports the + range of operations, and data sizes, needed by the + sqlite3_vfs and sqlite3_io_methods operations. Serialized + data are transient and this serialization algorithm may + change at any time. + + The data format can be succinctly summarized as: + + Nt...Td...D + + Where: + + - N = number of entries (1 byte) + + - t = type ID of first argument (1 byte) + + - ...T = type IDs of the 2nd and subsequent arguments (1 byte + each). + + - d = raw bytes of first argument (per-type size). + + - ...D = raw bytes of the 2nd and subsequent arguments (per-type + size). + + All types except strings have fixed sizes. Strings are stored + using their TextEncoder/TextDecoder representations. It would + arguably make more sense to store them as Int16Arrays of + their JS character values, but how best/fastest to get that + in and out of string form is an open point. Initial + experimentation with that approach did not gain us any speed. + + Historical note: this impl was initially about 1% this size by + using using JSON.stringify/parse(), but using fit-to-purpose + serialization saves considerable runtime. + */ + if(state.s11n) return state.s11n; + const textDecoder = new TextDecoder(), + textEncoder = new TextEncoder('utf-8'), + viewU8 = new Uint8Array(state.sabIO, state.sabS11nOffset, state.sabS11nSize), + viewDV = new DataView(state.sabIO, state.sabS11nOffset, state.sabS11nSize); + state.s11n = Object.create(null); + /* Only arguments and return values of these types may be + serialized. This covers the whole range of types needed by the + sqlite3_vfs API. */ + const TypeIds = Object.create(null); + TypeIds.number = { id: 1, size: 8, getter: 'getFloat64', setter: 'setFloat64' }; + TypeIds.bigint = { id: 2, size: 8, getter: 'getBigInt64', setter: 'setBigInt64' }; + TypeIds.boolean = { id: 3, size: 4, getter: 'getInt32', setter: 'setInt32' }; + TypeIds.string = { id: 4 }; + + const getTypeId = (v)=>( + TypeIds[typeof v] + || toss("Maintenance required: this value type cannot be serialized.",v) + ); + const getTypeIdById = (tid)=>{ + switch(tid){ + case TypeIds.number.id: return TypeIds.number; + case TypeIds.bigint.id: return TypeIds.bigint; + case TypeIds.boolean.id: return TypeIds.boolean; + case TypeIds.string.id: return TypeIds.string; + default: toss("Invalid type ID:",tid); + } + }; + + /** + Returns an array of the deserialized state stored by the most + recent serialize() operation (from from this thread or the + counterpart thread), or null if the serialization buffer is + empty. If passed a truthy argument, the serialization buffer + is cleared after deserialization. + */ + state.s11n.deserialize = function(clear=false){ + ++metrics.s11n.deserialize.count; + const t = performance.now(); + const argc = viewU8[0]; + const rc = argc ? [] : null; + if(argc){ + const typeIds = []; + let offset = 1, i, n, v; + for(i = 0; i < argc; ++i, ++offset){ + typeIds.push(getTypeIdById(viewU8[offset])); + } + for(i = 0; i < argc; ++i){ + const t = typeIds[i]; + if(t.getter){ + v = viewDV[t.getter](offset, state.littleEndian); + offset += t.size; + }else{/*String*/ + n = viewDV.getInt32(offset, state.littleEndian); + offset += 4; + v = textDecoder.decode(viewU8.slice(offset, offset+n)); + offset += n; + } + rc.push(v); + } + } + if(clear) viewU8[0] = 0; + //log("deserialize:",argc, rc); + metrics.s11n.deserialize.time += performance.now() - t; + return rc; + }; + + /** + Serializes all arguments to the shared buffer for consumption + by the counterpart thread. + + This routine is only intended for serializing OPFS VFS + arguments and (in at least one special case) result values, + and the buffer is sized to be able to comfortably handle + those. + + If passed no arguments then it zeroes out the serialization + state. + */ + state.s11n.serialize = function(...args){ + const t = performance.now(); + ++metrics.s11n.serialize.count; + if(args.length){ + //log("serialize():",args); + const typeIds = []; + let i = 0, offset = 1; + viewU8[0] = args.length & 0xff /* header = # of args */; + for(; i < args.length; ++i, ++offset){ + /* Write the TypeIds.id value into the next args.length + bytes. */ + typeIds.push(getTypeId(args[i])); + viewU8[offset] = typeIds[i].id; + } + for(i = 0; i < args.length; ++i) { + /* Deserialize the following bytes based on their + corresponding TypeIds.id from the header. */ + const t = typeIds[i]; + if(t.setter){ + viewDV[t.setter](offset, args[i], state.littleEndian); + offset += t.size; + }else{/*String*/ + const s = textEncoder.encode(args[i]); + viewDV.setInt32(offset, s.byteLength, state.littleEndian); + offset += 4; + viewU8.set(s, offset); + offset += s.byteLength; + } + } + //log("serialize() result:",viewU8.slice(0,offset)); + }else{ + viewU8[0] = 0; + } + metrics.s11n.serialize.time += performance.now() - t; + }; + return state.s11n; + }/*initS11n()*/; + + /** + Generates a random ASCII string len characters long, intended for + use as a temporary file name. + */ + const randomFilename = function f(len=16){ + if(!f._chars){ + f._chars = "abcdefghijklmnopqrstuvwxyz"+ + "ABCDEFGHIJKLMNOPQRSTUVWXYZ"+ + "012346789"; + f._n = f._chars.length; + } + const a = []; + let i = 0; + for( ; i < len; ++i){ + const ndx = Math.random() * (f._n * 64) % f._n | 0; + a[i] = f._chars[ndx]; + } + return a.join(''); + }; + + /** + Map of sqlite3_file pointers to objects constructed by xOpen(). + */ + const __openFiles = Object.create(null); + + /** + Installs a StructBinder-bound function pointer member of the + given name and function in the given StructType target object. + It creates a WASM proxy for the given function and arranges for + that proxy to be cleaned up when tgt.dispose() is called. Throws + on the slightest hint of error (e.g. tgt is-not-a StructType, + name does not map to a struct-bound member, etc.). + + Returns a proxy for this function which is bound to tgt and takes + 2 args (name,func). That function returns the same thing, + permitting calls to be chained. + + If called with only 1 arg, it has no side effects but returns a + func with the same signature as described above. + */ + const installMethod = function callee(tgt, name, func){ + if(!(tgt instanceof sqlite3.StructBinder.StructType)){ + toss("Usage error: target object is-not-a StructType."); + } + if(1===arguments.length){ + return (n,f)=>callee(tgt,n,f); + } + if(!callee.argcProxy){ + callee.argcProxy = function(func,sig){ + return function(...args){ + if(func.length!==arguments.length){ + toss("Argument mismatch. Native signature is:",sig); + } + return func.apply(this, args); + } + }; + callee.removeFuncList = function(){ + if(this.ondispose.__removeFuncList){ + this.ondispose.__removeFuncList.forEach( + (v,ndx)=>{ + if('number'===typeof v){ + try{wasm.uninstallFunction(v)} + catch(e){/*ignore*/} + } + /* else it's a descriptive label for the next number in + the list. */ + } + ); + delete this.ondispose.__removeFuncList; + } + }; + }/*static init*/ + const sigN = tgt.memberSignature(name); + if(sigN.length<2){ + toss("Member",name," is not a function pointer. Signature =",sigN); + } + const memKey = tgt.memberKey(name); + const fProxy = 0 + /** This middle-man proxy is only for use during development, to + confirm that we always pass the proper number of + arguments. We know that the C-level code will always use the + correct argument count. */ + ? callee.argcProxy(func, sigN) + : func; + const pFunc = wasm.installFunction(fProxy, tgt.memberSignature(name, true)); + tgt[memKey] = pFunc; + if(!tgt.ondispose) tgt.ondispose = []; + if(!tgt.ondispose.__removeFuncList){ + tgt.ondispose.push('ondispose.__removeFuncList handler', + callee.removeFuncList); + tgt.ondispose.__removeFuncList = []; + } + tgt.ondispose.__removeFuncList.push(memKey, pFunc); + return (n,f)=>callee(tgt, n, f); + }/*installMethod*/; + + const opTimer = Object.create(null); + opTimer.op = undefined; + opTimer.start = undefined; + const mTimeStart = (op)=>{ + opTimer.start = performance.now(); + opTimer.op = op; + ++metrics[op].count; + }; + const mTimeEnd = ()=>( + metrics[opTimer.op].time += performance.now() - opTimer.start + ); + + /** + Impls for the sqlite3_io_methods methods. Maintenance reminder: + members are in alphabetical order to simplify finding them. + */ + const ioSyncWrappers = { + xCheckReservedLock: function(pFile,pOut){ + /** + As of late 2022, only a single lock can be held on an OPFS + file. We have no way of checking whether any _other_ db + connection has a lock except by trying to obtain and (on + success) release a sync-handle for it, but doing so would + involve an inherent race condition. For the time being, + pending a better solution, we simply report whether the + given pFile instance has a lock. + */ + const f = __openFiles[pFile]; + wasm.setMemValue(pOut, f.lockMode ? 1 : 0, 'i32'); + return 0; + }, + xClose: function(pFile){ + mTimeStart('xClose'); + let rc = 0; + const f = __openFiles[pFile]; + if(f){ + delete __openFiles[pFile]; + rc = opRun('xClose', pFile); + if(f.sq3File) f.sq3File.dispose(); + } + mTimeEnd(); + return rc; + }, + xDeviceCharacteristics: function(pFile){ + //debug("xDeviceCharacteristics(",pFile,")"); + return capi.SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN; + }, + xFileControl: function(pFile, opId, pArg){ + mTimeStart('xFileControl'); + const rc = (capi.SQLITE_FCNTL_SYNC===opId) + ? opRun('xSync', pFile, 0) + : capi.SQLITE_NOTFOUND; + mTimeEnd(); + return rc; + }, + xFileSize: function(pFile,pSz64){ + mTimeStart('xFileSize'); + const rc = opRun('xFileSize', pFile); + if(0==rc){ + const sz = state.s11n.deserialize()[0]; + wasm.setMemValue(pSz64, sz, 'i64'); + } + mTimeEnd(); + return rc; + }, + xLock: function(pFile,lockType){ + mTimeStart('xLock'); + const f = __openFiles[pFile]; + let rc = 0; + if( capi.SQLITE_LOCK_NONE === f.lockType ) { + rc = opRun('xLock', pFile, lockType); + if( 0===rc ) f.lockType = lockType; + }else{ + f.lockType = lockType; + } + mTimeEnd(); + return rc; + }, + xRead: function(pFile,pDest,n,offset64){ + mTimeStart('xRead'); + const f = __openFiles[pFile]; + let rc; + try { + rc = opRun('xRead',pFile, n, Number(offset64)); + if(0===rc || capi.SQLITE_IOERR_SHORT_READ===rc){ + /** + Results get written to the SharedArrayBuffer f.sabView. + Because the heap is _not_ a SharedArrayBuffer, we have + to copy the results. TypedArray.set() seems to be the + fastest way to copy this. */ + wasm.heap8u().set(f.sabView.subarray(0, n), pDest); + } + }catch(e){ + error("xRead(",arguments,") failed:",e,f); + rc = capi.SQLITE_IOERR_READ; + } + mTimeEnd(); + return rc; + }, + xSync: function(pFile,flags){ + ++metrics.xSync.count; + return 0; // impl'd in xFileControl() + }, + xTruncate: function(pFile,sz64){ + mTimeStart('xTruncate'); + const rc = opRun('xTruncate', pFile, Number(sz64)); + mTimeEnd(); + return rc; + }, + xUnlock: function(pFile,lockType){ + mTimeStart('xUnlock'); + const f = __openFiles[pFile]; + let rc = 0; + if( capi.SQLITE_LOCK_NONE === lockType + && f.lockType ){ + rc = opRun('xUnlock', pFile, lockType); + } + if( 0===rc ) f.lockType = lockType; + mTimeEnd(); + return rc; + }, + xWrite: function(pFile,pSrc,n,offset64){ + mTimeStart('xWrite'); + const f = __openFiles[pFile]; + let rc; + try { + f.sabView.set(wasm.heap8u().subarray(pSrc, pSrc+n)); + rc = opRun('xWrite', pFile, n, Number(offset64)); + }catch(e){ + error("xWrite(",arguments,") failed:",e,f); + rc = capi.SQLITE_IOERR_WRITE; + } + mTimeEnd(); + return rc; + } + }/*ioSyncWrappers*/; + + /** + Impls for the sqlite3_vfs methods. Maintenance reminder: members + are in alphabetical order to simplify finding them. + */ + const vfsSyncWrappers = { + xAccess: function(pVfs,zName,flags,pOut){ + mTimeStart('xAccess'); + const rc = opRun('xAccess', wasm.cstringToJs(zName)); + wasm.setMemValue( pOut, (rc ? 0 : 1), 'i32' ); + mTimeEnd(); + return 0; + }, + xCurrentTime: function(pVfs,pOut){ + /* If it turns out that we need to adjust for timezone, see: + https://stackoverflow.com/a/11760121/1458521 */ + wasm.setMemValue(pOut, 2440587.5 + (new Date().getTime()/86400000), + 'double'); + return 0; + }, + xCurrentTimeInt64: function(pVfs,pOut){ + // TODO: confirm that this calculation is correct + wasm.setMemValue(pOut, (2440587.5 * 86400000) + new Date().getTime(), + 'i64'); + return 0; + }, + xDelete: function(pVfs, zName, doSyncDir){ + mTimeStart('xDelete'); + opRun('xDelete', wasm.cstringToJs(zName), doSyncDir, false); + /* We're ignoring errors because we cannot yet differentiate + between harmless and non-harmless failures. */ + mTimeEnd(); + return 0; + }, + xFullPathname: function(pVfs,zName,nOut,pOut){ + /* Until/unless we have some notion of "current dir" + in OPFS, simply copy zName to pOut... */ + const i = wasm.cstrncpy(pOut, zName, nOut); + return i<nOut ? 0 : capi.SQLITE_CANTOPEN + /*CANTOPEN is required by the docs but SQLITE_RANGE would be a closer match*/; + }, + xGetLastError: function(pVfs,nOut,pOut){ + /* TODO: store exception.message values from the async + partner in a dedicated SharedArrayBuffer, noting that we'd have + to encode them... TextEncoder can do that for us. */ + warn("OPFS xGetLastError() has nothing sensible to return."); + return 0; + }, + //xSleep is optionally defined below + xOpen: function f(pVfs, zName, pFile, flags, pOutFlags){ + mTimeStart('xOpen'); + if(0===zName){ + zName = randomFilename(); + }else if('number'===typeof zName){ + zName = wasm.cstringToJs(zName); + } + const fh = Object.create(null); + fh.fid = pFile; + fh.filename = zName; + fh.sab = new SharedArrayBuffer(state.fileBufferSize); + fh.flags = flags; + const rc = opRun('xOpen', pFile, zName, flags); + if(!rc){ + /* Recall that sqlite3_vfs::xClose() will be called, even on + error, unless pFile->pMethods is NULL. */ + if(fh.readOnly){ + wasm.setMemValue(pOutFlags, capi.SQLITE_OPEN_READONLY, 'i32'); + } + __openFiles[pFile] = fh; + fh.sabView = state.sabFileBufView; + fh.sq3File = new sqlite3_file(pFile); + fh.sq3File.$pMethods = opfsIoMethods.pointer; + fh.lockType = capi.SQLITE_LOCK_NONE; + } + mTimeEnd(); + return rc; + }/*xOpen()*/ + }/*vfsSyncWrappers*/; + + if(dVfs){ + opfsVfs.$xRandomness = dVfs.$xRandomness; + opfsVfs.$xSleep = dVfs.$xSleep; + } + if(!opfsVfs.$xRandomness){ + /* If the default VFS has no xRandomness(), add a basic JS impl... */ + vfsSyncWrappers.xRandomness = function(pVfs, nOut, pOut){ + const heap = wasm.heap8u(); + let i = 0; + for(; i < nOut; ++i) heap[pOut + i] = (Math.random()*255000) & 0xFF; + return i; + }; + } + if(!opfsVfs.$xSleep){ + /* If we can inherit an xSleep() impl from the default VFS then + assume it's sane and use it, otherwise install a JS-based + one. */ + vfsSyncWrappers.xSleep = function(pVfs,ms){ + Atomics.wait(state.sabOPView, state.opIds.xSleep, 0, ms); + return 0; + }; + } + + /* Install the vfs/io_methods into their C-level shared instances... */ + for(let k of Object.keys(ioSyncWrappers)){ + installMethod(opfsIoMethods, k, ioSyncWrappers[k]); + } + for(let k of Object.keys(vfsSyncWrappers)){ + installMethod(opfsVfs, k, vfsSyncWrappers[k]); + } + + /** + Expects an OPFS file path. It gets resolved, such that ".." + components are properly expanded, and returned. If the 2nd arg + is true, the result is returned as an array of path elements, + else an absolute path string is returned. + */ + opfsUtil.getResolvedPath = function(filename,splitIt){ + const p = new URL(filename, "file://irrelevant").pathname; + return splitIt ? p.split('/').filter((v)=>!!v) : p; + }; + + /** + Takes the absolute path to a filesystem element. Returns an + array of [handleOfContainingDir, filename]. If the 2nd argument + is truthy then each directory element leading to the file is + created along the way. Throws if any creation or resolution + fails. + */ + opfsUtil.getDirForFilename = async function f(absFilename, createDirs = false){ + const path = opfsUtil.getResolvedPath(absFilename, true); + const filename = path.pop(); + let dh = opfsUtil.rootDirectory; + for(const dirName of path){ + if(dirName){ + dh = await dh.getDirectoryHandle(dirName, {create: !!createDirs}); + } + } + return [dh, filename]; + }; + + /** + Creates the given directory name, recursively, in + the OPFS filesystem. Returns true if it succeeds or the + directory already exists, else false. + */ + opfsUtil.mkdir = async function(absDirName){ + try { + await opfsUtil.getDirForFilename(absDirName+"/filepart", true); + return true; + }catch(e){ + //console.warn("mkdir(",absDirName,") failed:",e); + return false; + } + }; + /** + Checks whether the given OPFS filesystem entry exists, + returning true if it does, false if it doesn't. + */ + opfsUtil.entryExists = async function(fsEntryName){ + try { + const [dh, fn] = await opfsUtil.getDirForFilename(fsEntryName); + await dh.getFileHandle(fn); + return true; + }catch(e){ + return false; + } + }; + + /** + Generates a random ASCII string, intended for use as a + temporary file name. Its argument is the length of the string, + defaulting to 16. + */ + opfsUtil.randomFilename = randomFilename; + + /** + Re-registers the OPFS VFS. This is intended only for odd use + cases which have to call sqlite3_shutdown() as part of their + initialization process, which will unregister the VFS + registered by installOpfsVfs(). If passed a truthy value, the + OPFS VFS is registered as the default VFS, else it is not made + the default. Returns the result of the the + sqlite3_vfs_register() call. + + Design note: the problem of having to re-register things after + a shutdown/initialize pair is more general. How to best plug + that in to the library is unclear. In particular, we cannot + hook in to any C-side calls to sqlite3_initialize(), so we + cannot add an after-initialize callback mechanism. + */ + opfsUtil.registerVfs = (asDefault=false)=>{ + return wasm.exports.sqlite3_vfs_register( + opfsVfs.pointer, asDefault ? 1 : 0 + ); + }; + + /** + Returns a promise which resolves to an object which represents + all files and directories in the OPFS tree. The top-most object + has two properties: `dirs` is an array of directory entries + (described below) and `files` is a list of file names for all + files in that directory. + + Traversal starts at sqlite3.opfs.rootDirectory. + + Each `dirs` entry is an object in this form: + + ``` + { name: directoryName, + dirs: [...subdirs], + files: [...file names] + } + ``` + + The `files` and `subdirs` entries are always set but may be + empty arrays. + + The returned object has the same structure but its `name` is + an empty string. All returned objects are created with + Object.create(null), so have no prototype. + + Design note: the entries do not contain more information, + e.g. file sizes, because getting such info is not only + expensive but is subject to locking-related errors. + */ + opfsUtil.treeList = async function(){ + const doDir = async function callee(dirHandle,tgt){ + tgt.name = dirHandle.name; + tgt.dirs = []; + tgt.files = []; + for await (const handle of dirHandle.values()){ + if('directory' === handle.kind){ + const subDir = Object.create(null); + tgt.dirs.push(subDir); + await callee(handle, subDir); + }else{ + tgt.files.push(handle.name); + } + } + }; + const root = Object.create(null); + await doDir(opfsUtil.rootDirectory, root); + return root; + }; + + /** + Irrevocably deletes _all_ files in the current origin's OPFS. + Obviously, this must be used with great caution. It may throw + an exception if removal of anything fails (e.g. a file is + locked), but the precise conditions under which it will throw + are not documented (so we cannot tell you what they are). + */ + opfsUtil.rmfr = async function(){ + const dir = opfsUtil.rootDirectory, opt = {recurse: true}; + for await (const handle of dir.values()){ + dir.removeEntry(handle.name, opt); + } + }; + + /** + Deletes the given OPFS filesystem entry. As this environment + has no notion of "current directory", the given name must be an + absolute path. If the 2nd argument is truthy, deletion is + recursive (use with caution!). + + The returned Promise resolves to true if the deletion was + successful, else false (but...). The OPFS API reports the + reason for the failure only in human-readable form, not + exceptions which can be type-checked to determine the + failure. Because of that... + + If the final argument is truthy then this function will + propagate any exception on error, rather than returning false. + */ + opfsUtil.unlink = async function(fsEntryName, recursive = false, + throwOnError = false){ + try { + const [hDir, filenamePart] = + await opfsUtil.getDirForFilename(fsEntryName, false); + await hDir.removeEntry(filenamePart, {recursive}); + return true; + }catch(e){ + if(throwOnError){ + throw new Error("unlink(",arguments[0],") failed: "+e.message,{ + cause: e + }); + } + return false; + } + }; + + /** + Traverses the OPFS filesystem, calling a callback for each one. + The argument may be either a callback function or an options object + with any of the following properties: + + - `callback`: function which gets called for each filesystem + entry. It gets passed 3 arguments: 1) the + FileSystemFileHandle or FileSystemDirectoryHandle of each + entry (noting that both are instanceof FileSystemHandle). 2) + the FileSystemDirectoryHandle of the parent directory. 3) the + current depth level, with 0 being at the top of the tree + relative to the starting directory. If the callback returns a + literal false, as opposed to any other falsy value, traversal + stops without an error. Any exceptions it throws are + propagated. Results are undefined if the callback manipulate + the filesystem (e.g. removing or adding entries) because the + how OPFS iterators behave in the face of such changes is + undocumented. + + - `recursive` [bool=true]: specifies whether to recurse into + subdirectories or not. Whether recursion is depth-first or + breadth-first is unspecified! + + - `directory` [FileSystemDirectoryEntry=sqlite3.opfs.rootDirectory] + specifies the starting directory. + + If this function is passed a function, it is assumed to be the + callback. + + Returns a promise because it has to (by virtue of being async) + but that promise has no specific meaning: the traversal it + performs is synchronous. The promise must be used to catch any + exceptions propagated by the callback, however. + + TODO: add an option which specifies whether to traverse + depth-first or breadth-first. We currently do depth-first but + an incremental file browsing widget would benefit more from + breadth-first. + */ + opfsUtil.traverse = async function(opt){ + const defaultOpt = { + recursive: true, + directory: opfsUtil.rootDirectory + }; + if('function'===typeof opt){ + opt = {callback:opt}; + } + opt = Object.assign(defaultOpt, opt||{}); + const doDir = async function callee(dirHandle, depth){ + for await (const handle of dirHandle.values()){ + if(false === opt.callback(handle, dirHandle, depth)) return false; + else if(opt.recursive && 'directory' === handle.kind){ + if(false === await callee(handle, depth + 1)) break; + } + } + }; + doDir(opt.directory, 0); + }; + + //TODO to support fiddle and worker1 db upload: + //opfsUtil.createFile = function(absName, content=undefined){...} + + if(sqlite3.oo1){ + opfsUtil.OpfsDb = function(...args){ + const opt = sqlite3.oo1.DB.dbCtorHelper.normalizeArgs(...args); + opt.vfs = opfsVfs.$zName; + sqlite3.oo1.DB.dbCtorHelper.call(this, opt); + }; + opfsUtil.OpfsDb.prototype = Object.create(sqlite3.oo1.DB.prototype); + sqlite3.oo1.DB.dbCtorHelper.setVfsPostOpenSql( + opfsVfs.pointer, + [ + /* Truncate journal mode is faster than delete or wal for + this vfs, per speedtest1. */ + "pragma journal_mode=truncate;" + /* + This vfs benefits hugely from cache on moderate/large + speedtest1 --size 50 and --size 100 workloads. We currently + rely on setting a non-default cache size when building + sqlite3.wasm. If that policy changes, the cache can + be set here. + */ + //"pragma cache_size=-8388608;" + ].join('') + ); + } + + /** + Potential TODOs: + + - Expose one or both of the Worker objects via opfsUtil and + publish an interface for proxying the higher-level OPFS + features like getting a directory listing. + */ + const sanityCheck = function(){ + const scope = wasm.scopedAllocPush(); + const sq3File = new sqlite3_file(); + try{ + const fid = sq3File.pointer; + const openFlags = capi.SQLITE_OPEN_CREATE + | capi.SQLITE_OPEN_READWRITE + //| capi.SQLITE_OPEN_DELETEONCLOSE + | capi.SQLITE_OPEN_MAIN_DB; + const pOut = wasm.scopedAlloc(8); + const dbFile = "/sanity/check/file"+randomFilename(8); + const zDbFile = wasm.scopedAllocCString(dbFile); + let rc; + state.s11n.serialize("This is ä string."); + rc = state.s11n.deserialize(); + log("deserialize() says:",rc); + if("This is ä string."!==rc[0]) toss("String d13n error."); + vfsSyncWrappers.xAccess(opfsVfs.pointer, zDbFile, 0, pOut); + rc = wasm.getMemValue(pOut,'i32'); + log("xAccess(",dbFile,") exists ?=",rc); + rc = vfsSyncWrappers.xOpen(opfsVfs.pointer, zDbFile, + fid, openFlags, pOut); + log("open rc =",rc,"state.sabOPView[xOpen] =", + state.sabOPView[state.opIds.xOpen]); + if(0!==rc){ + error("open failed with code",rc); + return; + } + vfsSyncWrappers.xAccess(opfsVfs.pointer, zDbFile, 0, pOut); + rc = wasm.getMemValue(pOut,'i32'); + if(!rc) toss("xAccess() failed to detect file."); + rc = ioSyncWrappers.xSync(sq3File.pointer, 0); + if(rc) toss('sync failed w/ rc',rc); + rc = ioSyncWrappers.xTruncate(sq3File.pointer, 1024); + if(rc) toss('truncate failed w/ rc',rc); + wasm.setMemValue(pOut,0,'i64'); + rc = ioSyncWrappers.xFileSize(sq3File.pointer, pOut); + if(rc) toss('xFileSize failed w/ rc',rc); + log("xFileSize says:",wasm.getMemValue(pOut, 'i64')); + rc = ioSyncWrappers.xWrite(sq3File.pointer, zDbFile, 10, 1); + if(rc) toss("xWrite() failed!"); + const readBuf = wasm.scopedAlloc(16); + rc = ioSyncWrappers.xRead(sq3File.pointer, readBuf, 6, 2); + wasm.setMemValue(readBuf+6,0); + let jRead = wasm.cstringToJs(readBuf); + log("xRead() got:",jRead); + if("sanity"!==jRead) toss("Unexpected xRead() value."); + if(vfsSyncWrappers.xSleep){ + log("xSleep()ing before close()ing..."); + vfsSyncWrappers.xSleep(opfsVfs.pointer,2000); + log("waking up from xSleep()"); + } + rc = ioSyncWrappers.xClose(fid); + log("xClose rc =",rc,"sabOPView =",state.sabOPView); + log("Deleting file:",dbFile); + vfsSyncWrappers.xDelete(opfsVfs.pointer, zDbFile, 0x1234); + vfsSyncWrappers.xAccess(opfsVfs.pointer, zDbFile, 0, pOut); + rc = wasm.getMemValue(pOut,'i32'); + if(rc) toss("Expecting 0 from xAccess(",dbFile,") after xDelete()."); + warn("End of OPFS sanity checks."); + }finally{ + sq3File.dispose(); + wasm.scopedAllocPop(scope); + } + }/*sanityCheck()*/; + + W.onmessage = function({data}){ + //log("Worker.onmessage:",data); + switch(data.type){ + case 'opfs-async-loaded': + /*Arrives as soon as the asyc proxy finishes loading. + Pass our config and shared state on to the async worker.*/ + W.postMessage({type: 'opfs-async-init',args: state}); + break; + case 'opfs-async-inited':{ + /*Indicates that the async partner has received the 'init' + and has finished initializing, so the real work can + begin...*/ + try { + const rc = capi.sqlite3_vfs_register(opfsVfs.pointer, 0); + if(rc){ + toss("sqlite3_vfs_register(OPFS) failed with rc",rc); + } + if(opfsVfs.pointer !== capi.sqlite3_vfs_find("opfs")){ + toss("BUG: sqlite3_vfs_find() failed for just-installed OPFS VFS"); + } + capi.sqlite3_vfs_register.addReference(opfsVfs, opfsIoMethods); + state.sabOPView = new Int32Array(state.sabOP); + state.sabFileBufView = new Uint8Array(state.sabIO, 0, state.fileBufferSize); + state.sabS11nView = new Uint8Array(state.sabIO, state.sabS11nOffset, state.sabS11nSize); + initS11n(); + if(options.sanityChecks){ + warn("Running sanity checks because of opfs-sanity-check URL arg..."); + sanityCheck(); + } + navigator.storage.getDirectory().then((d)=>{ + W.onerror = W._originalOnError; + delete W._originalOnError; + sqlite3.opfs = opfsUtil; + opfsUtil.rootDirectory = d; + log("End of OPFS sqlite3_vfs setup.", opfsVfs); + promiseResolve(sqlite3); + }); + }catch(e){ + error(e); + promiseReject(e); + } + break; + } + default: + promiseReject(e); + error("Unexpected message from the async worker:",data); + break; + }/*switch(data.type)*/ + }/*W.onmessage()*/; + })/*thePromise*/; + return thePromise; +}/*installOpfsVfs()*/; +installOpfsVfs.defaultProxyUri = + "sqlite3-opfs-async-proxy.js"; +self.sqlite3ApiBootstrap.initializersAsync.push(async (sqlite3)=>{ + if(sqlite3.scriptInfo && !sqlite3.scriptInfo.isWorker){ + return; + } + try{ + let proxyJs = installOpfsVfs.defaultProxyUri; + if(sqlite3.scriptInfo.sqlite3Dir){ + installOpfsVfs.defaultProxyUri = + sqlite3.scriptInfo.sqlite3Dir + proxyJs; + //console.warn("installOpfsVfs.defaultProxyUri =",installOpfsVfs.defaultProxyUri); + } + return installOpfsVfs().catch((e)=>{ + console.warn("Ignoring inability to install OPFS sqlite3_vfs:",e.message); + }); + }catch(e){ + console.error("installOpfsVfs() exception:",e); + throw e; + } +}); +}/*sqlite3ApiBootstrap.initializers.push()*/); |