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+/*
+** 2022-11-30
+**
+** 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 installs sqlite3.vfs, a namespace of helpers for use in
+ the creation of JavaScript implementations of sqlite3_vfs.
+*/
+'use strict';
+globalThis.sqlite3ApiBootstrap.initializers.push(function(sqlite3){
+ const wasm = sqlite3.wasm, capi = sqlite3.capi, toss = sqlite3.util.toss3;
+ const vfs = Object.create(null);
+ sqlite3.vfs = vfs;
+
+ /**
+ Uses sqlite3_vfs_register() to register this
+ sqlite3.capi.sqlite3_vfs instance. This object must have already
+ been filled out properly. If the first argument is truthy, the
+ VFS is registered as the default VFS, else it is not.
+
+ On success, returns this object. Throws on error.
+ */
+ capi.sqlite3_vfs.prototype.registerVfs = function(asDefault=false){
+ if(!(this instanceof sqlite3.capi.sqlite3_vfs)){
+ toss("Expecting a sqlite3_vfs-type argument.");
+ }
+ const rc = capi.sqlite3_vfs_register(this, asDefault ? 1 : 0);
+ if(rc){
+ toss("sqlite3_vfs_register(",this,") failed with rc",rc);
+ }
+ if(this.pointer !== capi.sqlite3_vfs_find(this.$zName)){
+ toss("BUG: sqlite3_vfs_find(vfs.$zName) failed for just-installed VFS",
+ this);
+ }
+ return this;
+ };
+
+ /**
+ A wrapper for
+ sqlite3.StructBinder.StructType.prototype.installMethods() or
+ registerVfs() to reduce installation of a VFS and/or its I/O
+ methods to a single call.
+
+ Accepts an object which contains the properties "io" and/or
+ "vfs", each of which is itself an object with following properties:
+
+ - `struct`: an sqlite3.StructBinder.StructType-type struct. This
+ must be a populated (except for the methods) object of type
+ sqlite3_io_methods (for the "io" entry) or sqlite3_vfs (for the
+ "vfs" entry).
+
+ - `methods`: an object mapping sqlite3_io_methods method names
+ (e.g. 'xClose') to JS implementations of those methods. The JS
+ implementations must be call-compatible with their native
+ counterparts.
+
+ For each of those object, this function passes its (`struct`,
+ `methods`, (optional) `applyArgcCheck`) properties to
+ installMethods().
+
+ If the `vfs` entry is set then:
+
+ - Its `struct` property's registerVfs() is called. The
+ `vfs` entry may optionally have an `asDefault` property, which
+ gets passed as the argument to registerVfs().
+
+ - If `struct.$zName` is falsy and the entry has a string-type
+ `name` property, `struct.$zName` is set to the C-string form of
+ that `name` value before registerVfs() is called. That string
+ gets added to the on-dispose state of the struct.
+
+ On success returns this object. Throws on error.
+ */
+ vfs.installVfs = function(opt){
+ let count = 0;
+ const propList = ['io','vfs'];
+ for(const key of propList){
+ const o = opt[key];
+ if(o){
+ ++count;
+ o.struct.installMethods(o.methods, !!o.applyArgcCheck);
+ if('vfs'===key){
+ if(!o.struct.$zName && 'string'===typeof o.name){
+ o.struct.addOnDispose(
+ o.struct.$zName = wasm.allocCString(o.name)
+ );
+ }
+ o.struct.registerVfs(!!o.asDefault);
+ }
+ }
+ }
+ if(!count) toss("Misuse: installVfs() options object requires at least",
+ "one of:", propList);
+ return this;
+ };
+}/*sqlite3ApiBootstrap.initializers.push()*/);