style improvements, dead code elimination

Author: JoeOsborn

src/library_fetchfs.js

@@ -8,9 +8,7 @@ addToLibrary({
   $FETCHFS__deps: ['$stringToUTF8OnStack', 'wasmfs_create_fetch_backend', 'wasmfs_fetch_create_manifest', 'wasmfs_fetch_add_to_manifest'],
   $FETCHFS: {
     createBackend(opts) {
-      if(opts.base_url === undefined) {
-        opts.base_url = "";
-      }
+      opts.base_url ??= "";
       return withStackSave(() => {
         var manifest = 0;
         if (opts['manifest']) {

src/library_wasmfs_fetch.js

@@ -31,12 +31,12 @@ addToLibrary({
         try {
           var u = new URL(fileUrl, self.location.origin);
           url = u.toString();
-        } catch(_e) {
+        } catch (_e) {
           throw {status: 404};
         }
       }
       var chunkSize = __wasmfs_fetch_get_chunk_size(file);
-      offset = offset || 0;
+      offset ??= 0;
       len = len || chunkSize;
       var firstChunk = (offset / chunkSize) | 0;
       var lastChunk = ((offset+len) / chunkSize) | 0;

system/lib/wasmfs/backends/fetch_backend.cpp

@@ -178,11 +178,6 @@ extern "C" {
     [](backend_t backend) { _wasmfs_create_fetch_backend_js(backend); }));
   }
 
-const char* _wasmfs_fetch_get_file_path(void* ptr) {
-  auto* file = reinterpret_cast<wasmfs::FetchFile*>(ptr);
-  return file ? file->getPath().data() : nullptr;
-}
-
 const char* _wasmfs_fetch_get_file_url(void* ptr) {
   auto* file = reinterpret_cast<wasmfs::FetchFile*>(ptr);
   return file ? file->getURL().data() : nullptr;