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Diffstat (limited to 'ext/wasm/api/sqlite3-vfs-opfs-sahpool.c-pp.js')
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diff --git a/ext/wasm/api/sqlite3-vfs-opfs-sahpool.c-pp.js b/ext/wasm/api/sqlite3-vfs-opfs-sahpool.c-pp.js new file mode 100644 index 0000000..870073c --- /dev/null +++ b/ext/wasm/api/sqlite3-vfs-opfs-sahpool.c-pp.js @@ -0,0 +1,1287 @@ +//#ifnot target=node +/* + 2023-07-14 + + 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 a sqlite3_vfs backed by OPFS storage which uses a + different implementation strategy than the "opfs" VFS. This one is a + port of Roy Hashimoto's OPFS SyncAccessHandle pool: + + https://github.com/rhashimoto/wa-sqlite/blob/master/src/examples/AccessHandlePoolVFS.js + + As described at: + + https://github.com/rhashimoto/wa-sqlite/discussions/67 + + with Roy's explicit permission to permit us to port his to our + infrastructure rather than having to clean-room reverse-engineer it: + + https://sqlite.org/forum/forumpost/e140d84e71 + + Primary differences from the "opfs" VFS include: + + - This one avoids the need for a sub-worker to synchronize + communication between the synchronous C API and the + only-partly-synchronous OPFS API. + + - It does so by opening a fixed number of OPFS files at + library-level initialization time, obtaining SyncAccessHandles to + each, and manipulating those handles via the synchronous sqlite3_vfs + interface. If it cannot open them (e.g. they are already opened by + another tab) then the VFS will not be installed. + + - Because of that, this one lacks all library-level concurrency + support. + + - Also because of that, it does not require the SharedArrayBuffer, + so can function without the COOP/COEP HTTP response headers. + + - It can hypothetically support Safari 16.4+, whereas the "opfs" VFS + requires v17 due to a subworker/storage bug in 16.x which makes it + incompatible with that VFS. + + - This VFS requires the "semi-fully-sync" FileSystemSyncAccessHandle + (hereafter "SAH") APIs released with Chrome v108 (and all other + major browsers released since March 2023). If that API is not + detected, the VFS is not registered. +*/ +globalThis.sqlite3ApiBootstrap.initializers.push(function(sqlite3){ + 'use strict'; + const toss = sqlite3.util.toss; + const toss3 = sqlite3.util.toss3; + const initPromises = Object.create(null); + const capi = sqlite3.capi; + const util = sqlite3.util; + const wasm = sqlite3.wasm; + // Config opts for the VFS... + const SECTOR_SIZE = 4096; + const HEADER_MAX_PATH_SIZE = 512; + const HEADER_FLAGS_SIZE = 4; + const HEADER_DIGEST_SIZE = 8; + const HEADER_CORPUS_SIZE = HEADER_MAX_PATH_SIZE + HEADER_FLAGS_SIZE; + const HEADER_OFFSET_FLAGS = HEADER_MAX_PATH_SIZE; + const HEADER_OFFSET_DIGEST = HEADER_CORPUS_SIZE; + const HEADER_OFFSET_DATA = SECTOR_SIZE; + /* Bitmask of file types which may persist across sessions. + SQLITE_OPEN_xyz types not listed here may be inadvertently + left in OPFS but are treated as transient by this VFS and + they will be cleaned up during VFS init. */ + const PERSISTENT_FILE_TYPES = + capi.SQLITE_OPEN_MAIN_DB | + capi.SQLITE_OPEN_MAIN_JOURNAL | + capi.SQLITE_OPEN_SUPER_JOURNAL | + capi.SQLITE_OPEN_WAL /* noting that WAL support is + unavailable in the WASM build.*/; + + /** Subdirectory of the VFS's space where "opaque" (randomly-named) + files are stored. Changing this effectively invalidates the data + stored under older names (orphaning it), so don't do that. */ + const OPAQUE_DIR_NAME = ".opaque"; + + /** + Returns short a string of random alphanumeric characters + suitable for use as a random filename. + */ + const getRandomName = ()=>Math.random().toString(36).slice(2); + + const textDecoder = new TextDecoder(); + const textEncoder = new TextEncoder(); + + const optionDefaults = Object.assign(Object.create(null),{ + name: 'opfs-sahpool', + directory: undefined /* derived from .name */, + initialCapacity: 6, + clearOnInit: false, + /* Logging verbosity 3+ == everything, 2 == warnings+errors, 1 == + errors only. */ + verbosity: 2 + }); + + /** Logging routines, from most to least serious. */ + const loggers = [ + sqlite3.config.error, + sqlite3.config.warn, + sqlite3.config.log + ]; + const log = sqlite3.config.log; + const warn = sqlite3.config.warn; + const error = sqlite3.config.error; + + /* Maps (sqlite3_vfs*) to OpfsSAHPool instances */ + const __mapVfsToPool = new Map(); + const getPoolForVfs = (pVfs)=>__mapVfsToPool.get(pVfs); + const setPoolForVfs = (pVfs,pool)=>{ + if(pool) __mapVfsToPool.set(pVfs, pool); + else __mapVfsToPool.delete(pVfs); + }; + /* Maps (sqlite3_file*) to OpfsSAHPool instances */ + const __mapSqlite3File = new Map(); + const getPoolForPFile = (pFile)=>__mapSqlite3File.get(pFile); + const setPoolForPFile = (pFile,pool)=>{ + if(pool) __mapSqlite3File.set(pFile, pool); + else __mapSqlite3File.delete(pFile); + }; + + /** + Impls for the sqlite3_io_methods methods. Maintenance reminder: + members are in alphabetical order to simplify finding them. + */ + const ioMethods = { + xCheckReservedLock: function(pFile,pOut){ + const pool = getPoolForPFile(pFile); + pool.log('xCheckReservedLock'); + pool.storeErr(); + wasm.poke32(pOut, 1); + return 0; + }, + xClose: function(pFile){ + const pool = getPoolForPFile(pFile); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + if(file) { + try{ + pool.log(`xClose ${file.path}`); + pool.mapS3FileToOFile(pFile, false); + file.sah.flush(); + if(file.flags & capi.SQLITE_OPEN_DELETEONCLOSE){ + pool.deletePath(file.path); + } + }catch(e){ + return pool.storeErr(e, capi.SQLITE_IOERR); + } + } + return 0; + }, + xDeviceCharacteristics: function(pFile){ + return capi.SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN; + }, + xFileControl: function(pFile, opId, pArg){ + return capi.SQLITE_NOTFOUND; + }, + xFileSize: function(pFile,pSz64){ + const pool = getPoolForPFile(pFile); + pool.log(`xFileSize`); + const file = pool.getOFileForS3File(pFile); + const size = file.sah.getSize() - HEADER_OFFSET_DATA; + //log(`xFileSize ${file.path} ${size}`); + wasm.poke64(pSz64, BigInt(size)); + return 0; + }, + xLock: function(pFile,lockType){ + const pool = getPoolForPFile(pFile); + pool.log(`xLock ${lockType}`); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + file.lockType = lockType; + return 0; + }, + xRead: function(pFile,pDest,n,offset64){ + const pool = getPoolForPFile(pFile); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + pool.log(`xRead ${file.path} ${n} @ ${offset64}`); + try { + const nRead = file.sah.read( + wasm.heap8u().subarray(pDest, pDest+n), + {at: HEADER_OFFSET_DATA + Number(offset64)} + ); + if(nRead < n){ + wasm.heap8u().fill(0, pDest + nRead, pDest + n); + return capi.SQLITE_IOERR_SHORT_READ; + } + return 0; + }catch(e){ + return pool.storeErr(e, capi.SQLITE_IOERR); + } + }, + xSectorSize: function(pFile){ + return SECTOR_SIZE; + }, + xSync: function(pFile,flags){ + const pool = getPoolForPFile(pFile); + pool.log(`xSync ${flags}`); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + //log(`xSync ${file.path} ${flags}`); + try{ + file.sah.flush(); + return 0; + }catch(e){ + return pool.storeErr(e, capi.SQLITE_IOERR); + } + }, + xTruncate: function(pFile,sz64){ + const pool = getPoolForPFile(pFile); + pool.log(`xTruncate ${sz64}`); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + //log(`xTruncate ${file.path} ${iSize}`); + try{ + file.sah.truncate(HEADER_OFFSET_DATA + Number(sz64)); + return 0; + }catch(e){ + return pool.storeErr(e, capi.SQLITE_IOERR); + } + }, + xUnlock: function(pFile,lockType){ + const pool = getPoolForPFile(pFile); + pool.log('xUnlock'); + const file = pool.getOFileForS3File(pFile); + file.lockType = lockType; + return 0; + }, + xWrite: function(pFile,pSrc,n,offset64){ + const pool = getPoolForPFile(pFile); + pool.storeErr(); + const file = pool.getOFileForS3File(pFile); + pool.log(`xWrite ${file.path} ${n} ${offset64}`); + try{ + const nBytes = file.sah.write( + wasm.heap8u().subarray(pSrc, pSrc+n), + { at: HEADER_OFFSET_DATA + Number(offset64) } + ); + return n===nBytes ? 0 : toss("Unknown write() failure."); + }catch(e){ + return pool.storeErr(e, capi.SQLITE_IOERR); + } + } + }/*ioMethods*/; + + const opfsIoMethods = new capi.sqlite3_io_methods(); + opfsIoMethods.$iVersion = 1; + sqlite3.vfs.installVfs({ + io: {struct: opfsIoMethods, methods: ioMethods} + }); + + /** + Impls for the sqlite3_vfs methods. Maintenance reminder: members + are in alphabetical order to simplify finding them. + */ + const vfsMethods = { + xAccess: function(pVfs,zName,flags,pOut){ + //log(`xAccess ${wasm.cstrToJs(zName)}`); + const pool = getPoolForVfs(pVfs); + pool.storeErr(); + try{ + const name = pool.getPath(zName); + wasm.poke32(pOut, pool.hasFilename(name) ? 1 : 0); + }catch(e){ + /*ignored*/ + wasm.poke32(pOut, 0); + } + return 0; + }, + xCurrentTime: function(pVfs,pOut){ + wasm.poke(pOut, 2440587.5 + (new Date().getTime()/86400000), + 'double'); + return 0; + }, + xCurrentTimeInt64: function(pVfs,pOut){ + wasm.poke(pOut, (2440587.5 * 86400000) + new Date().getTime(), + 'i64'); + return 0; + }, + xDelete: function(pVfs, zName, doSyncDir){ + const pool = getPoolForVfs(pVfs); + pool.log(`xDelete ${wasm.cstrToJs(zName)}`); + pool.storeErr(); + try{ + pool.deletePath(pool.getPath(zName)); + return 0; + }catch(e){ + pool.storeErr(e); + return capi.SQLITE_IOERR_DELETE; + } + }, + xFullPathname: function(pVfs,zName,nOut,pOut){ + //const pool = getPoolForVfs(pVfs); + //pool.log(`xFullPathname ${wasm.cstrToJs(zName)}`); + const i = wasm.cstrncpy(pOut, zName, nOut); + return i<nOut ? 0 : capi.SQLITE_CANTOPEN; + }, + xGetLastError: function(pVfs,nOut,pOut){ + const pool = getPoolForVfs(pVfs); + const e = pool.popErr(); + pool.log(`xGetLastError ${nOut} e =`,e); + if(e){ + const scope = wasm.scopedAllocPush(); + try{ + const [cMsg, n] = wasm.scopedAllocCString(e.message, true); + wasm.cstrncpy(pOut, cMsg, nOut); + if(n > nOut) wasm.poke8(pOut + nOut - 1, 0); + }catch(e){ + return capi.SQLITE_NOMEM; + }finally{ + wasm.scopedAllocPop(scope); + } + } + return e ? (e.sqlite3Rc || capi.SQLITE_IOERR) : 0; + }, + //xSleep is optionally defined below + xOpen: function f(pVfs, zName, pFile, flags, pOutFlags){ + const pool = getPoolForVfs(pVfs); + try{ + pool.log(`xOpen ${wasm.cstrToJs(zName)} ${flags}`); + // First try to open a path that already exists in the file system. + const path = (zName && wasm.peek8(zName)) + ? pool.getPath(zName) + : getRandomName(); + let sah = pool.getSAHForPath(path); + if(!sah && (flags & capi.SQLITE_OPEN_CREATE)) { + // File not found so try to create it. + if(pool.getFileCount() < pool.getCapacity()) { + // Choose an unassociated OPFS file from the pool. + sah = pool.nextAvailableSAH(); + pool.setAssociatedPath(sah, path, flags); + }else{ + // File pool is full. + toss('SAH pool is full. Cannot create file',path); + } + } + if(!sah){ + toss('file not found:',path); + } + // Subsequent I/O methods are only passed the sqlite3_file + // pointer, so map the relevant info we need to that pointer. + const file = {path, flags, sah}; + pool.mapS3FileToOFile(pFile, file); + file.lockType = capi.SQLITE_LOCK_NONE; + const sq3File = new capi.sqlite3_file(pFile); + sq3File.$pMethods = opfsIoMethods.pointer; + sq3File.dispose(); + wasm.poke32(pOutFlags, flags); + return 0; + }catch(e){ + pool.storeErr(e); + return capi.SQLITE_CANTOPEN; + } + }/*xOpen()*/ + }/*vfsMethods*/; + + /** + Creates and initializes an sqlite3_vfs instance for an + OpfsSAHPool. The argument is the VFS's name (JS string). + + Throws if the VFS name is already registered or if something + goes terribly wrong via sqlite3.vfs.installVfs(). + + Maintenance reminder: the only detail about the returned object + which is specific to any given OpfsSAHPool instance is the $zName + member. All other state is identical. + */ + const createOpfsVfs = function(vfsName){ + if( sqlite3.capi.sqlite3_vfs_find(vfsName)){ + toss3("VFS name is already registered:", vfsName); + } + const opfsVfs = new capi.sqlite3_vfs(); + /* We fetch the default VFS so that we can inherit some + methods from it. */ + const pDVfs = capi.sqlite3_vfs_find(null); + const dVfs = pDVfs + ? new capi.sqlite3_vfs(pDVfs) + : null /* dVfs will be null when sqlite3 is built with + SQLITE_OS_OTHER. */; + opfsVfs.$iVersion = 2/*yes, two*/; + opfsVfs.$szOsFile = capi.sqlite3_file.structInfo.sizeof; + opfsVfs.$mxPathname = HEADER_MAX_PATH_SIZE; + opfsVfs.addOnDispose( + opfsVfs.$zName = wasm.allocCString(vfsName), + ()=>setPoolForVfs(opfsVfs.pointer, 0) + ); + + if(dVfs){ + /* Inherit certain VFS members from the default VFS, + if available. */ + opfsVfs.$xRandomness = dVfs.$xRandomness; + opfsVfs.$xSleep = dVfs.$xSleep; + dVfs.dispose(); + } + if(!opfsVfs.$xRandomness && !vfsMethods.xRandomness){ + /* If the default VFS has no xRandomness(), add a basic JS impl... */ + vfsMethods.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.$xSleep && !vfsMethods.xSleep){ + vfsMethods.xSleep = (pVfs,ms)=>0; + } + sqlite3.vfs.installVfs({ + vfs: {struct: opfsVfs, methods: vfsMethods} + }); + return opfsVfs; + }; + + /** + Class for managing OPFS-related state for the + OPFS SharedAccessHandle Pool sqlite3_vfs. + */ + class OpfsSAHPool { + /* OPFS dir in which VFS metadata is stored. */ + vfsDir; + /* Directory handle to this.vfsDir. */ + #dhVfsRoot; + /* Directory handle to the subdir of this.#dhVfsRoot which holds + the randomly-named "opaque" files. This subdir exists in the + hope that we can eventually support client-created files in + this.#dhVfsRoot. */ + #dhOpaque; + /* Directory handle to this.dhVfsRoot's parent dir. Needed + for a VFS-wipe op. */ + #dhVfsParent; + /* Maps SAHs to their opaque file names. */ + #mapSAHToName = new Map(); + /* Maps client-side file names to SAHs. */ + #mapFilenameToSAH = new Map(); + /* Set of currently-unused SAHs. */ + #availableSAH = new Set(); + /* Maps (sqlite3_file*) to xOpen's file objects. */ + #mapS3FileToOFile_ = new Map(); + + /* Maps SAH to an abstract File Object which contains + various metadata about that handle. */ + //#mapSAHToMeta = new Map(); + + /** Buffer used by [sg]etAssociatedPath(). */ + #apBody = new Uint8Array(HEADER_CORPUS_SIZE); + // DataView for this.#apBody + #dvBody; + + // associated sqlite3_vfs instance + #cVfs; + + // Logging verbosity. See optionDefaults.verbosity. + #verbosity; + + constructor(options = Object.create(null)){ + this.#verbosity = options.verbosity ?? optionDefaults.verbosity; + this.vfsName = options.name || optionDefaults.name; + this.#cVfs = createOpfsVfs(this.vfsName); + setPoolForVfs(this.#cVfs.pointer, this); + this.vfsDir = options.directory || ("."+this.vfsName); + this.#dvBody = + new DataView(this.#apBody.buffer, this.#apBody.byteOffset); + this.isReady = this + .reset(!!(options.clearOnInit ?? optionDefaults.clearOnInit)) + .then(()=>{ + if(this.$error) throw this.$error; + return this.getCapacity() + ? Promise.resolve(undefined) + : this.addCapacity(options.initialCapacity + || optionDefaults.initialCapacity); + }); + } + + #logImpl(level,...args){ + if(this.#verbosity>level) loggers[level](this.vfsName+":",...args); + }; + log(...args){this.#logImpl(2, ...args)}; + warn(...args){this.#logImpl(1, ...args)}; + error(...args){this.#logImpl(0, ...args)}; + + getVfs(){return this.#cVfs} + + /* Current pool capacity. */ + getCapacity(){return this.#mapSAHToName.size} + + /* Current number of in-use files from pool. */ + getFileCount(){return this.#mapFilenameToSAH.size} + + /* Returns an array of the names of all + currently-opened client-specified filenames. */ + getFileNames(){ + const rc = []; + const iter = this.#mapFilenameToSAH.keys(); + for(const n of iter) rc.push(n); + return rc; + } + +// #createFileObject(sah,clientName,opaqueName){ +// const f = Object.assign(Object.create(null),{ +// clientName, opaqueName +// }); +// this.#mapSAHToMeta.set(sah, f); +// return f; +// } +// #unmapFileObject(sah){ +// this.#mapSAHToMeta.delete(sah); +// } + + /** + Adds n files to the pool's capacity. This change is + persistent across settings. Returns a Promise which resolves + to the new capacity. + */ + async addCapacity(n){ + for(let i = 0; i < n; ++i){ + const name = getRandomName(); + const h = await this.#dhOpaque.getFileHandle(name, {create:true}); + const ah = await h.createSyncAccessHandle(); + this.#mapSAHToName.set(ah,name); + this.setAssociatedPath(ah, '', 0); + //this.#createFileObject(ah,undefined,name); + } + return this.getCapacity(); + } + + /** + Reduce capacity by n, but can only reduce up to the limit + of currently-available SAHs. Returns a Promise which resolves + to the number of slots really removed. + */ + async reduceCapacity(n){ + let nRm = 0; + for(const ah of Array.from(this.#availableSAH)){ + if(nRm === n || this.getFileCount() === this.getCapacity()){ + break; + } + const name = this.#mapSAHToName.get(ah); + //this.#unmapFileObject(ah); + ah.close(); + await this.#dhOpaque.removeEntry(name); + this.#mapSAHToName.delete(ah); + this.#availableSAH.delete(ah); + ++nRm; + } + return nRm; + } + + /** + Releases all currently-opened SAHs. The only legal + operation after this is acquireAccessHandles(). + */ + releaseAccessHandles(){ + for(const ah of this.#mapSAHToName.keys()) ah.close(); + this.#mapSAHToName.clear(); + this.#mapFilenameToSAH.clear(); + this.#availableSAH.clear(); + } + + /** + Opens all files under this.vfsDir/this.#dhOpaque and acquires + a SAH for each. returns a Promise which resolves to no value + but completes once all SAHs are acquired. If acquiring an SAH + throws, SAHPool.$error will contain the corresponding + exception. + + If clearFiles is true, the client-stored state of each file is + cleared when its handle is acquired, including its name, flags, + and any data stored after the metadata block. + */ + async acquireAccessHandles(clearFiles){ + const files = []; + for await (const [name,h] of this.#dhOpaque){ + if('file'===h.kind){ + files.push([name,h]); + } + } + return Promise.all(files.map(async([name,h])=>{ + try{ + const ah = await h.createSyncAccessHandle() + this.#mapSAHToName.set(ah, name); + if(clearFiles){ + ah.truncate(HEADER_OFFSET_DATA); + this.setAssociatedPath(ah, '', 0); + }else{ + const path = this.getAssociatedPath(ah); + if(path){ + this.#mapFilenameToSAH.set(path, ah); + }else{ + this.#availableSAH.add(ah); + } + } + }catch(e){ + this.storeErr(e); + this.releaseAccessHandles(); + throw e; + } + })); + } + + /** + Given an SAH, returns the client-specified name of + that file by extracting it from the SAH's header. + + On error, it disassociates SAH from the pool and + returns an empty string. + */ + getAssociatedPath(sah){ + sah.read(this.#apBody, {at: 0}); + // Delete any unexpected files left over by previous + // untimely errors... + const flags = this.#dvBody.getUint32(HEADER_OFFSET_FLAGS); + if(this.#apBody[0] && + ((flags & capi.SQLITE_OPEN_DELETEONCLOSE) || + (flags & PERSISTENT_FILE_TYPES)===0)){ + warn(`Removing file with unexpected flags ${flags.toString(16)}`, + this.#apBody); + this.setAssociatedPath(sah, '', 0); + return ''; + } + + const fileDigest = new Uint32Array(HEADER_DIGEST_SIZE / 4); + sah.read(fileDigest, {at: HEADER_OFFSET_DIGEST}); + const compDigest = this.computeDigest(this.#apBody); + if(fileDigest.every((v,i) => v===compDigest[i])){ + // Valid digest + const pathBytes = this.#apBody.findIndex((v)=>0===v); + if(0===pathBytes){ + // This file is unassociated, so truncate it to avoid + // leaving stale db data laying around. + sah.truncate(HEADER_OFFSET_DATA); + } + return pathBytes + ? textDecoder.decode(this.#apBody.subarray(0,pathBytes)) + : ''; + }else{ + // Invalid digest + warn('Disassociating file with bad digest.'); + this.setAssociatedPath(sah, '', 0); + return ''; + } + } + + /** + Stores the given client-defined path and SQLITE_OPEN_xyz flags + into the given SAH. If path is an empty string then the file is + disassociated from the pool but its previous name is preserved + in the metadata. + */ + setAssociatedPath(sah, path, flags){ + const enc = textEncoder.encodeInto(path, this.#apBody); + if(HEADER_MAX_PATH_SIZE <= enc.written + 1/*NUL byte*/){ + toss("Path too long:",path); + } + this.#apBody.fill(0, enc.written, HEADER_MAX_PATH_SIZE); + this.#dvBody.setUint32(HEADER_OFFSET_FLAGS, flags); + + const digest = this.computeDigest(this.#apBody); + sah.write(this.#apBody, {at: 0}); + sah.write(digest, {at: HEADER_OFFSET_DIGEST}); + sah.flush(); + + if(path){ + this.#mapFilenameToSAH.set(path, sah); + this.#availableSAH.delete(sah); + }else{ + // This is not a persistent file, so eliminate the contents. + sah.truncate(HEADER_OFFSET_DATA); + this.#availableSAH.add(sah); + } + } + + /** + Computes a digest for the given byte array and returns it as a + two-element Uint32Array. This digest gets stored in the + metadata for each file as a validation check. Changing this + algorithm invalidates all existing databases for this VFS, so + don't do that. + */ + computeDigest(byteArray){ + let h1 = 0xdeadbeef; + let h2 = 0x41c6ce57; + for(const v of byteArray){ + h1 = 31 * h1 + (v * 307); + h2 = 31 * h2 + (v * 307); + } + return new Uint32Array([h1>>>0, h2>>>0]); + } + + /** + Re-initializes the state of the SAH pool, releasing and + re-acquiring all handles. + + See acquireAccessHandles() for the specifics of the clearFiles + argument. + */ + async reset(clearFiles){ + await this.isReady; + let h = await navigator.storage.getDirectory(); + let prev, prevName; + for(const d of this.vfsDir.split('/')){ + if(d){ + prev = h; + h = await h.getDirectoryHandle(d,{create:true}); + } + } + this.#dhVfsRoot = h; + this.#dhVfsParent = prev; + this.#dhOpaque = await this.#dhVfsRoot.getDirectoryHandle( + OPAQUE_DIR_NAME,{create:true} + ); + this.releaseAccessHandles(); + return this.acquireAccessHandles(clearFiles); + } + + /** + Returns the pathname part of the given argument, + which may be any of: + + - a URL object + - A JS string representing a file name + - Wasm C-string representing a file name + + All "../" parts and duplicate slashes are resolve/removed from + the returned result. + */ + getPath(arg) { + if(wasm.isPtr(arg)) arg = wasm.cstrToJs(arg); + return ((arg instanceof URL) + ? arg + : new URL(arg, 'file://localhost/')).pathname; + } + + /** + Removes the association of the given client-specified file + name (JS string) from the pool. Returns true if a mapping + is found, else false. + */ + deletePath(path) { + const sah = this.#mapFilenameToSAH.get(path); + if(sah) { + // Un-associate the name from the SAH. + this.#mapFilenameToSAH.delete(path); + this.setAssociatedPath(sah, '', 0); + } + return !!sah; + } + + /** + Sets e (an Error object) as this object's current error. Pass a + falsy (or no) value to clear it. If code is truthy it is + assumed to be an SQLITE_xxx result code, defaulting to + SQLITE_IOERR if code is falsy. + + Returns the 2nd argument. + */ + storeErr(e,code){ + if(e){ + e.sqlite3Rc = code || capi.SQLITE_IOERR; + this.error(e); + } + this.$error = e; + return code; + } + /** + Pops this object's Error object and returns + it (a falsy value if no error is set). + */ + popErr(){ + const rc = this.$error; + this.$error = undefined; + return rc; + } + + /** + Returns the next available SAH without removing + it from the set. + */ + nextAvailableSAH(){ + const [rc] = this.#availableSAH.keys(); + return rc; + } + + /** + Given an (sqlite3_file*), returns the mapped + xOpen file object. + */ + getOFileForS3File(pFile){ + return this.#mapS3FileToOFile_.get(pFile); + } + /** + Maps or unmaps (if file is falsy) the given (sqlite3_file*) + to an xOpen file object and to this pool object. + */ + mapS3FileToOFile(pFile,file){ + if(file){ + this.#mapS3FileToOFile_.set(pFile, file); + setPoolForPFile(pFile, this); + }else{ + this.#mapS3FileToOFile_.delete(pFile); + setPoolForPFile(pFile, false); + } + } + + /** + Returns true if the given client-defined file name is in this + object's name-to-SAH map. + */ + hasFilename(name){ + return this.#mapFilenameToSAH.has(name) + } + + /** + Returns the SAH associated with the given + client-defined file name. + */ + getSAHForPath(path){ + return this.#mapFilenameToSAH.get(path); + } + + /** + Removes this object's sqlite3_vfs registration and shuts down + this object, releasing all handles, mappings, and whatnot, + including deleting its data directory. There is currently no + way to "revive" the object and reaquire its resources. + + This function is intended primarily for testing. + + Resolves to true if it did its job, false if the + VFS has already been shut down. + */ + async removeVfs(){ + if(!this.#cVfs.pointer || !this.#dhOpaque) return false; + capi.sqlite3_vfs_unregister(this.#cVfs.pointer); + this.#cVfs.dispose(); + try{ + this.releaseAccessHandles(); + await this.#dhVfsRoot.removeEntry(OPAQUE_DIR_NAME, {recursive: true}); + this.#dhOpaque = undefined; + await this.#dhVfsParent.removeEntry( + this.#dhVfsRoot.name, {recursive: true} + ); + this.#dhVfsRoot = this.#dhVfsParent = undefined; + }catch(e){ + sqlite3.config.error(this.vfsName,"removeVfs() failed:",e); + /*otherwise ignored - there is no recovery strategy*/ + } + return true; + } + + + //! Documented elsewhere in this file. + exportFile(name){ + const sah = this.#mapFilenameToSAH.get(name) || toss("File not found:",name); + const n = sah.getSize() - HEADER_OFFSET_DATA; + const b = new Uint8Array(n>0 ? n : 0); + if(n>0){ + const nRead = sah.read(b, {at: HEADER_OFFSET_DATA}); + if(nRead != n){ + toss("Expected to read "+n+" bytes but read "+nRead+"."); + } + } + return b; + } + + //! Impl for importDb() when its 2nd arg is a function. + async importDbChunked(name, callback){ + const sah = this.#mapFilenameToSAH.get(name) + || this.nextAvailableSAH() + || toss("No available handles to import to."); + sah.truncate(0); + let nWrote = 0, chunk, checkedHeader = false, err = false; + try{ + while( undefined !== (chunk = await callback()) ){ + if(chunk instanceof ArrayBuffer) chunk = new Uint8Array(chunk); + if( 0===nWrote && chunk.byteLength>=15 ){ + util.affirmDbHeader(chunk); + checkedHeader = true; + } + sah.write(chunk, {at: HEADER_OFFSET_DATA + nWrote}); + nWrote += chunk.byteLength; + } + if( nWrote < 512 || 0!==nWrote % 512 ){ + toss("Input size",nWrote,"is not correct for an SQLite database."); + } + if( !checkedHeader ){ + const header = new Uint8Array(20); + sah.read( header, {at: 0} ); + util.affirmDbHeader( header ); + } + sah.write(new Uint8Array([1,1]), { + at: HEADER_OFFSET_DATA + 18 + }/*force db out of WAL mode*/); + }catch(e){ + this.setAssociatedPath(sah, '', 0); + throw e; + } + this.setAssociatedPath(sah, name, capi.SQLITE_OPEN_MAIN_DB); + return nWrote; + } + + //! Documented elsewhere in this file. + importDb(name, bytes){ + if( bytes instanceof ArrayBuffer ) bytes = new Uint8Array(bytes); + else if( bytes instanceof Function ) return this.importDbChunked(name, bytes); + const sah = this.#mapFilenameToSAH.get(name) + || this.nextAvailableSAH() + || toss("No available handles to import to."); + const n = bytes.byteLength; + if(n<512 || n%512!=0){ + toss("Byte array size is invalid for an SQLite db."); + } + const header = "SQLite format 3"; + for(let i = 0; i < header.length; ++i){ + if( header.charCodeAt(i) !== bytes[i] ){ + toss("Input does not contain an SQLite database header."); + } + } + const nWrote = sah.write(bytes, {at: HEADER_OFFSET_DATA}); + if(nWrote != n){ + this.setAssociatedPath(sah, '', 0); + toss("Expected to write "+n+" bytes but wrote "+nWrote+"."); + }else{ + sah.write(new Uint8Array([1,1]), {at: HEADER_OFFSET_DATA+18} + /* force db out of WAL mode */); + this.setAssociatedPath(sah, name, capi.SQLITE_OPEN_MAIN_DB); + } + return nWrote; + } + + }/*class OpfsSAHPool*/; + + + /** + A OpfsSAHPoolUtil instance is exposed to clients in order to + manipulate an OpfsSAHPool object without directly exposing that + object and allowing for some semantic changes compared to that + class. + + Class docs are in the client-level docs for + installOpfsSAHPoolVfs(). + */ + class OpfsSAHPoolUtil { + /* This object's associated OpfsSAHPool. */ + #p; + + constructor(sahPool){ + this.#p = sahPool; + this.vfsName = sahPool.vfsName; + } + + async addCapacity(n){ return this.#p.addCapacity(n) } + + async reduceCapacity(n){ return this.#p.reduceCapacity(n) } + + getCapacity(){ return this.#p.getCapacity(this.#p) } + + getFileCount(){ return this.#p.getFileCount() } + getFileNames(){ return this.#p.getFileNames() } + + async reserveMinimumCapacity(min){ + const c = this.#p.getCapacity(); + return (c < min) ? this.#p.addCapacity(min - c) : c; + } + + exportFile(name){ return this.#p.exportFile(name) } + + importDb(name, bytes){ return this.#p.importDb(name,bytes) } + + async wipeFiles(){ return this.#p.reset(true) } + + unlink(filename){ return this.#p.deletePath(filename) } + + async removeVfs(){ return this.#p.removeVfs() } + + }/* class OpfsSAHPoolUtil */; + + /** + Returns a resolved Promise if the current environment + has a "fully-sync" SAH impl, else a rejected Promise. + */ + const apiVersionCheck = async ()=>{ + const dh = await navigator.storage.getDirectory(); + const fn = '.opfs-sahpool-sync-check-'+getRandomName(); + const fh = await dh.getFileHandle(fn, { create: true }); + const ah = await fh.createSyncAccessHandle(); + const close = ah.close(); + await close; + await dh.removeEntry(fn); + if(close?.then){ + toss("The local OPFS API is too old for opfs-sahpool:", + "it has an async FileSystemSyncAccessHandle.close() method."); + } + return true; + }; + + /** Only for testing a rejection case. */ + let instanceCounter = 0; + + /** + installOpfsSAHPoolVfs() asynchronously initializes the OPFS + SyncAccessHandle (a.k.a. SAH) Pool VFS. It returns a Promise which + either resolves to a utility object described below or rejects with + an Error value. + + Initialization of this VFS is not automatic because its + registration requires that it lock all resources it + will potentially use, even if client code does not want + to use them. That, in turn, can lead to locking errors + when, for example, one page in a given origin has loaded + this VFS but does not use it, then another page in that + origin tries to use the VFS. If the VFS were automatically + registered, the second page would fail to load the VFS + due to OPFS locking errors. + + If this function is called more than once with a given "name" + option (see below), it will return the same Promise. Calls for + different names will return different Promises which resolve to + independent objects and refer to different VFS registrations. + + On success, the resulting Promise resolves to a utility object + which can be used to query and manipulate the pool. Its API is + described at the end of these docs. + + This function accepts an options object to configure certain + parts but it is only acknowledged for the very first call and + ignored for all subsequent calls. + + The options, in alphabetical order: + + - `clearOnInit`: (default=false) if truthy, contents and filename + mapping are removed from each SAH it is acquired during + initalization of the VFS, leaving the VFS's storage in a pristine + state. Use this only for databases which need not survive a page + reload. + + - `initialCapacity`: (default=6) Specifies the default capacity of + the VFS. This should not be set unduly high because the VFS has + to open (and keep open) a file for each entry in the pool. This + setting only has an effect when the pool is initially empty. It + does not have any effect if a pool already exists. + + - `directory`: (default="."+`name`) Specifies the OPFS directory + name in which to store metadata for the `"opfs-sahpool"` + sqlite3_vfs. Only one instance of this VFS can be installed per + JavaScript engine, and any two engines with the same storage + directory name will collide with each other, leading to locking + errors and the inability to register the VFS in the second and + subsequent engine. Using a different directory name for each + application enables different engines in the same HTTP origin to + co-exist, but their data are invisible to each other. Changing + this name will effectively orphan any databases stored under + previous names. The default is unspecified but descriptive. This + option may contain multiple path elements, e.g. "foo/bar/baz", + and they are created automatically. In practice there should be + no driving need to change this. ACHTUNG: all files in this + directory are assumed to be managed by the VFS. Do not place + other files in that directory, as they may be deleted or + otherwise modified by the VFS. + + - `name`: (default="opfs-sahpool") sets the name to register this + VFS under. Normally this should not be changed, but it is + possible to register this VFS under multiple names so long as + each has its own separate directory to work from. The storage for + each is invisible to all others. The name must be a string + compatible with `sqlite3_vfs_register()` and friends and suitable + for use in URI-style database file names. + + Achtung: if a custom `name` is provided, a custom `directory` + must also be provided if any other instance is registered with + the default directory. If no directory is explicitly provided + then a directory name is synthesized from the `name` option. + + Peculiarities of this VFS: + + - Paths given to it _must_ be absolute. Relative paths will not + be properly recognized. This is arguably a bug but correcting it + requires some hoop-jumping in routines which have no business + doing tricks. + + - It is possible to install multiple instances under different + names, each sandboxed from one another inside their own private + directory. This feature exists primarily as a way for disparate + applications within a given HTTP origin to use this VFS without + introducing locking issues between them. + + + The API for the utility object passed on by this function's + Promise, in alphabetical order... + + - [async] number addCapacity(n) + + Adds `n` entries to the current pool. This change is persistent + across sessions so should not be called automatically at each app + startup (but see `reserveMinimumCapacity()`). Its returned Promise + resolves to the new capacity. Because this operation is necessarily + asynchronous, the C-level VFS API cannot call this on its own as + needed. + + - byteArray exportFile(name) + + Synchronously reads the contents of the given file into a Uint8Array + and returns it. This will throw if the given name is not currently + in active use or on I/O error. Note that the given name is _not_ + visible directly in OPFS (or, if it is, it's not from this VFS). + + - number getCapacity() + + Returns the number of files currently contained + in the SAH pool. The default capacity is only large enough for one + or two databases and their associated temp files. + + - number getFileCount() + + Returns the number of files from the pool currently allocated to + slots. This is not the same as the files being "opened". + + - array getFileNames() + + Returns an array of the names of the files currently allocated to + slots. This list is the same length as getFileCount(). + + - void importDb(name, bytes) + + Imports the contents of an SQLite database, provided as a byte + array or ArrayBuffer, under the given name, overwriting any + existing content. Throws if the pool has no available file slots, + on I/O error, or if the input does not appear to be a + database. In the latter case, only a cursory examination is made. + Note that this routine is _only_ for importing database files, + not arbitrary files, the reason being that this VFS will + automatically clean up any non-database files so importing them + is pointless. + + If passed a function for its second argument, its behavior + changes to asynchronous and it imports its data in chunks fed to + it by the given callback function. It calls the callback (which + may be async) repeatedly, expecting either a Uint8Array or + ArrayBuffer (to denote new input) or undefined (to denote + EOF). For so long as the callback continues to return + non-undefined, it will append incoming data to the given + VFS-hosted database file. The result of the resolved Promise when + called this way is the size of the resulting database. + + On succes this routine rewrites the database header bytes in the + output file (not the input array) to force disabling of WAL mode. + + On a write error, the handle is removed from the pool and made + available for re-use. + + - [async] number reduceCapacity(n) + + Removes up to `n` entries from the pool, with the caveat that it can + only remove currently-unused entries. It returns a Promise which + resolves to the number of entries actually removed. + + - [async] boolean removeVfs() + + Unregisters the opfs-sahpool VFS and removes its directory from OPFS + (which means that _all client content_ is removed). After calling + this, the VFS may no longer be used and there is no way to re-add it + aside from reloading the current JavaScript context. + + Results are undefined if a database is currently in use with this + VFS. + + The returned Promise resolves to true if it performed the removal + and false if the VFS was not installed. + + If the VFS has a multi-level directory, e.g. "/foo/bar/baz", _only_ + the bottom-most directory is removed because this VFS cannot know for + certain whether the higher-level directories contain data which + should be removed. + + - [async] number reserveMinimumCapacity(min) + + If the current capacity is less than `min`, the capacity is + increased to `min`, else this returns with no side effects. The + resulting Promise resolves to the new capacity. + + - boolean unlink(filename) + + If a virtual file exists with the given name, disassociates it from + the pool and returns true, else returns false without side + effects. Results are undefined if the file is currently in active + use. + + - string vfsName + + The SQLite VFS name under which this pool's VFS is registered. + + - [async] void wipeFiles() + + Clears all client-defined state of all SAHs and makes all of them + available for re-use by the pool. Results are undefined if any such + handles are currently in use, e.g. by an sqlite3 db. + */ + sqlite3.installOpfsSAHPoolVfs = async function(options=Object.create(null)){ + const vfsName = options.name || optionDefaults.name; + if(0 && 2===++instanceCounter){ + throw new Error("Just testing rejection."); + } + if(initPromises[vfsName]){ + //console.warn("Returning same OpfsSAHPool result",options,vfsName,initPromises[vfsName]); + return initPromises[vfsName]; + } + if(!globalThis.FileSystemHandle || + !globalThis.FileSystemDirectoryHandle || + !globalThis.FileSystemFileHandle || + !globalThis.FileSystemFileHandle.prototype.createSyncAccessHandle || + !navigator?.storage?.getDirectory){ + return (initPromises[vfsName] = Promise.reject(new Error("Missing required OPFS APIs."))); + } + + /** + Maintenance reminder: the order of ASYNC ops in this function + is significant. We need to have them all chained at the very + end in order to be able to catch a race condition where + installOpfsSAHPoolVfs() is called twice in rapid succession, + e.g.: + + installOpfsSAHPoolVfs().then(console.warn.bind(console)); + installOpfsSAHPoolVfs().then(console.warn.bind(console)); + + If the timing of the async calls is not "just right" then that + second call can end up triggering the init a second time and chaos + ensues. + */ + return initPromises[vfsName] = apiVersionCheck().then(async function(){ + if(options.$testThrowInInit){ + throw options.$testThrowInInit; + } + const thePool = new OpfsSAHPool(options); + return thePool.isReady.then(async()=>{ + /** The poolUtil object will be the result of the + resolved Promise. */ + const poolUtil = new OpfsSAHPoolUtil(thePool); + if(sqlite3.oo1){ + const oo1 = sqlite3.oo1; + const theVfs = thePool.getVfs(); + const OpfsSAHPoolDb = function(...args){ + const opt = oo1.DB.dbCtorHelper.normalizeArgs(...args); + opt.vfs = theVfs.$zName; + oo1.DB.dbCtorHelper.call(this, opt); + }; + OpfsSAHPoolDb.prototype = Object.create(oo1.DB.prototype); + // yes or no? OpfsSAHPoolDb.PoolUtil = poolUtil; + poolUtil.OpfsSAHPoolDb = OpfsSAHPoolDb; + oo1.DB.dbCtorHelper.setVfsPostOpenSql( + theVfs.pointer, + function(oo1Db, sqlite3){ + sqlite3.capi.sqlite3_exec(oo1Db, [ + /* See notes in sqlite3-vfs-opfs.js */ + "pragma journal_mode=DELETE;", + "pragma cache_size=-16384;" + ], 0, 0, 0); + } + ); + }/*extend sqlite3.oo1*/ + thePool.log("VFS initialized."); + return poolUtil; + }).catch(async (e)=>{ + await thePool.removeVfs().catch(()=>{}); + return e; + }); + }).catch((err)=>{ + //error("rejecting promise:",err); + return initPromises[vfsName] = Promise.reject(err); + }); + }/*installOpfsSAHPoolVfs()*/; +}/*sqlite3ApiBootstrap.initializers*/); +//#else +/* + The OPFS SAH Pool VFS parts are elided from builds targeting + node.js. +*/ +//#endif target=node |