Apply considerable acrobatics to get the JS/WASM deliverables building to and loadable from a directory other than the one which contains the app-level code. Requires an only-slightly-leaky abstraction of passing a URL argument when loading sqlite3.js but provides much greater flexibility in where the JS/WASM files are located.

FossilOrigin-Name: 6d468dab9eb84d4548f68014959f02fe4f66455472ff24fe729382bb2972e3d1

1 files changed, 37 insertions, 8 deletions

diff --git a/ext/wasm/api/extern-post-js.js b/ext/wasm/api/extern-post-js.js
index 7dba03b3a..5f5f72d4b 100644
--- a/ext/wasm/api/extern-post-js.js
+++ b/ext/wasm/api/extern-post-js.js
@@ -16,6 +16,27 @@
   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)=>{
@@ -32,6 +53,8 @@
             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();
@@ -41,13 +64,19 @@
     });
   };
   self.sqlite3InitModule.ready = originalInit.ready;
-  //console.warn("Replaced sqlite3InitModule()");
-})();
 
-if(0){
-  console.warn("self.location.href =",self.location.href);
-  if('undefined' !== typeof document){
-    console.warn("document.currentScript.src =",
-                 document?.currentScript?.src);
+  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);
+    }
+  }
+})();