Fiddle: replace db export routine with a C-side one which works for both Emscripten FS-hosted and OPFS-hosted db files. Minor code-adjacent cleanups.

FossilOrigin-Name: 3579a8d6f1f6cd3cd8aad9949536870c5fe7bae8c1778f700dd85d763e266b94

3 files changed, 21 insertions, 63 deletions

diff --git a/ext/wasm/api/sqlite3-api-oo1.js b/ext/wasm/api/sqlite3-api-oo1.js
index 25ca34dda..e0f812baa 100644
--- a/ext/wasm/api/sqlite3-api-oo1.js
+++ b/ext/wasm/api/sqlite3-api-oo1.js
@@ -1025,51 +1025,6 @@ self.sqlite3ApiBootstrap.initializers.push(function(sqlite3){
         this.exec("ROLLBACK to SAVEPOINT oo1; RELEASE SAVEPOINT oo1");
         throw e;
       }
-    },
-    
-    /**
-       This function currently does nothing and always throws.  It
-       WILL BE REMOVED pending other refactoring, to eliminate a hard
-       dependency on Emscripten. This feature will be moved into a
-       higher-level API or a runtime-configurable feature.
-
-       That said, what its replacement should eventually do is...
-
-       Exports a copy of this db's file as a Uint8Array and
-       returns it. It is technically not legal to call this while
-       any prepared statement are currently active because,
-       depending on the platform, it might not be legal to read
-       the db while a statement is locking it. Throws if this db
-       is not open or has any opened statements.
-
-       The resulting buffer can be passed to this class's
-       constructor to restore the DB.
-
-       Maintenance reminder: the corresponding sql.js impl of this
-       feature closes the current db, finalizing any active
-       statements and (seemingly unnecessarily) destroys any UDFs,
-       copies the file, and then re-opens it (without restoring
-       the UDFs). Those gymnastics are not necessary on the tested
-       platform but might be necessary on others. Because of that
-       eventuality, this interface currently enforces that no
-       statements are active when this is run. It will throw if
-       any are.
-    */
-    exportBinaryImage: function(){
-      toss3("exportBinaryImage() is slated for removal for portability reasons.");
-      /***********************
-         The following is currently kept only for reference when
-         porting to some other layer, noting that we may well not be
-         able to implement this, at this level, when using the OPFS
-         VFS because of its exclusive locking policy.
-
-         affirmDbOpen(this);
-         if(this.openStatementCount()>0){
-           toss3("Cannot export with prepared statements active!",
-                 "finalize() all statements and try again.");
-         }
-         return MODCFG.FS.readFile(this.filename, {encoding:"binary"});
-      ***********************/
     }
   }/*DB.prototype*/;
 
diff --git a/ext/wasm/api/sqlite3-api-opfs.js b/ext/wasm/api/sqlite3-api-opfs.js
index 2c22c03f7..e28e47ab6 100644
--- a/ext/wasm/api/sqlite3-api-opfs.js
+++ b/ext/wasm/api/sqlite3-api-opfs.js
@@ -637,7 +637,7 @@ sqlite3.installOpfsVfs = function callee(asyncProxyUri = callee.defaultProxyUri)
         const rc = opRun('xFileSize', pFile);
         if(0==rc){
           const sz = state.s11n.deserialize()[0];
-          wasm.setMemValue(pSz64, BigInt(sz), 'i64');
+          wasm.setMemValue(pSz64, sz, 'i64');
         }
         mTimeEnd();
         return rc;
@@ -820,10 +820,12 @@ sqlite3.installOpfsVfs = function callee(asyncProxyUri = callee.defaultProxyUri)
     }
 
     /* Install the vfs/io_methods into their C-level shared instances... */
-    let inst = installMethod(opfsIoMethods);
-    for(let k of Object.keys(ioSyncWrappers)) inst(k, ioSyncWrappers[k]);
-    inst = installMethod(opfsVfs);
-    for(let k of Object.keys(vfsSyncWrappers)) inst(k, vfsSyncWrappers[k]);
+    for(let k of Object.keys(ioSyncWrappers)){
+      installMethod(opfsIoMethods, k, ioSyncWrappers[k]);
+    }
+    for(let k of Object.keys(vfsSyncWrappers)){
+      installMethod(opfsVfs, k, vfsSyncWrappers[k]);
+    }
 
     /**
        Syncronously deletes the given OPFS filesystem entry, ignoring
@@ -831,7 +833,7 @@ sqlite3.installOpfsVfs = function callee(asyncProxyUri = callee.defaultProxyUri)
        directory", the given name must be an absolute path. If the 2nd
        argument is truthy, deletion is recursive (use with caution!).
 
-       Returns true if the deletion succeeded and fails if it fails,
+       Returns true if the deletion succeeded and false if it fails,
        but cannot report the nature of the failure.
     */
     opfsUtil.deleteEntry = function(fsEntryName,recursive=false){
diff --git a/ext/wasm/api/sqlite3-api-prologue.js b/ext/wasm/api/sqlite3-api-prologue.js
index 6a3bbc585..b5cd292fc 100644
--- a/ext/wasm/api/sqlite3-api-prologue.js
+++ b/ext/wasm/api/sqlite3-api-prologue.js
@@ -784,13 +784,16 @@ self.sqlite3ApiBootstrap = function sqlite3ApiBootstrap(
   }
 
   /**
-     Given an `sqlite3*` and an sqlite3_vfs name, returns a truthy
-     value (see below) if that db handle uses that VFS, else returns
-     false. If pDb is falsy then this function returns a truthy value
-     if the default VFS is that VFS. Results are undefined if pDb is
-     truthy but refers to an invalid pointer.
-
-     The 2nd argument may either be a JS string or a C-string
+     Given an `sqlite3*`, an sqlite3_vfs name, and an optional db
+     name, returns a truthy value (see below) if that db handle uses
+     that VFS, else returns false. If pDb is falsy then the 3rd
+     argument is ignored and this function returns a truthy value if
+     the default VFS name matches that of the 2nd argument. Results
+     are undefined if pDb is truthy but refers to an invalid
+     pointer. The 3rd argument specifies the database name of the
+     given database connection to check, defaulting to the main db.
+
+     The 2nd and 3rd arguments may either be a JS string or a C-string
      allocated from the wasm environment.
 
      The truthy value it returns is a pointer to the `sqlite3_vfs`
@@ -801,11 +804,9 @@ self.sqlite3ApiBootstrap = function sqlite3ApiBootstrap(
      bad arguments cause a conversion error when passing into
      wasm-space, false is returned.
   */
-  capi.sqlite3_web_db_uses_vfs = function(pDb,vfsName){
+  capi.sqlite3_web_db_uses_vfs = function(pDb,vfsName,dbName="main"){
     try{
-      const pK = ('number'===vfsName)
-            ? capi.wasm.exports.sqlite3_vfs_find(vfsName)
-            : capi.sqlite3_vfs_find(vfsName);
+      const pK = capi.sqlite3_vfs_find(vfsName);
       if(!pK) return false;
       else if(!pDb){
         return capi.sqlite3_vfs_find(0)===pK ? pK : false;
@@ -814,7 +815,7 @@ self.sqlite3ApiBootstrap = function sqlite3ApiBootstrap(
       try{
         return (
           (0===capi.sqlite3_file_control(
-            pDb, "main", capi.SQLITE_FCNTL_VFS_POINTER, ppVfs
+            pDb, dbName, capi.SQLITE_FCNTL_VFS_POINTER, ppVfs
           )) && (capi.wasm.getPtrValue(ppVfs) === pK)
         ) ? pK : false;
       }finally{