1
0
mirror of https://github.com/sqlite/sqlite.git synced 2025-04-28 06:25:11 +03:00
sqlite/ext/wasm/api/extern-post-js.js

83 lines
3.2 KiB
JavaScript

/* extern-post-js.js must be appended to the resulting sqlite3.js
file. It gets its name from being used as the value for
the --extern-post-js=... Emscripten flag. */
(function(){
/**
In order to hide the sqlite3InitModule()'s resulting Emscripten
module from downstream clients (and simplify our documentation by
being able to elide those details), we rewrite
sqlite3InitModule() to return the sqlite3 object.
Unfortunately, we cannot modify the module-loader/exporter-based
impls which Emscripten installs at some point in the file above
this.
*/
const originalInit = self.sqlite3InitModule;
if(!originalInit){
throw new Error("Expecting self.sqlite3InitModule to be defined by the Emscripten build.");
}
/**
We need to add some state which our custom Module.locateFile()
can see, but an Emscripten limitation currently prevents us from
attaching it to the sqlite3InitModule function object:
https://github.com/emscripten-core/emscripten/issues/18071
The only current workaround is to temporarily stash this state
into the global scope and delete it when sqlite3InitModule()
is called.
*/
const initModuleState = self.sqlite3InitModuleState = Object.assign(Object.create(null),{
moduleScript: self?.document?.currentScript,
isWorker: (!self.document && self.window !== self),
location: self.location,
urlParams: new URL(self.location.href).searchParams
});
if(initModuleState.urlParams.has('sqlite3.dir')){
initModuleState.sqlite3Dir = initModuleState.urlParams.get('sqlite3.dir') +'/';
};
self.sqlite3InitModule = (...args)=>{
//console.warn("Using replaced sqlite3InitModule()",self.location);
return originalInit(...args).then((EmscriptenModule)=>{
if(self.window!==self &&
(EmscriptenModule['ENVIRONMENT_IS_PTHREAD']
|| EmscriptenModule['_pthread_self']
|| 'function'===typeof threadAlert
|| self.location.pathname.endsWith('.worker.js')
)){
/** Workaround for wasmfs-generated worker, which calls this
routine from each individual thread and requires that its
argument be returned. All of the criteria above are fragile,
based solely on inspection of the offending code, not public
Emscripten details. */
return EmscriptenModule;
}
EmscriptenModule.sqlite3.scriptInfo = initModuleState;
//console.warn("sqlite3.scriptInfo =",EmscriptenModule.sqlite3.scriptInfo);
const f = EmscriptenModule.sqlite3.asyncPostInit;
delete EmscriptenModule.sqlite3.asyncPostInit;
return f();
}).catch((e)=>{
console.error("Exception loading sqlite3 module:",e);
throw e;
});
};
self.sqlite3InitModule.ready = originalInit.ready;
if(self.sqlite3InitModuleState.moduleScript){
const sim = self.sqlite3InitModuleState;
let src = sim.moduleScript.src.split('/');
src.pop();
sim.scriptDir = src.join('/') + '/';
}
if(0){
console.warn("Replaced sqlite3InitModule()");
console.warn("self.location.href =",self.location.href);
if('undefined' !== typeof document){
console.warn("document.currentScript.src =",
document?.currentScript?.src);
}
}
})();