From 56b8c85e3fffb58695f4cd5f4526d40c14afc0f8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=94=D0=BC=D0=B8=D1=82=D1=80=D0=B8=D0=B9=20=D0=A6=D0=B5?=
 =?UTF-8?q?=D0=BD=D0=B5=D0=BA=D0=BE=D0=B2?=
 <49730476+DimaThenekov@users.noreply.github.com>
Date: Sat, 15 Nov 2025 19:56:24 +0300
Subject: [PATCH] Adding zstd_decompress to the filestore

---
 lib/filesystem.js          |  4 ++--
 src/browser/filestorage.js | 22 ++++++++++++++++------
 src/browser/starter.js     |  2 +-
 3 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/lib/filesystem.js b/lib/filesystem.js
index 6d9262aa..24b5e160 100644
--- a/lib/filesystem.js
+++ b/lib/filesystem.js
@@ -1068,7 +1068,7 @@ FS.prototype.get_buffer = async function(idx)
     else if(inode.status === STATUS_ON_STORAGE)
     {
         dbg_assert(inode.sha256sum, "Filesystem get_data: found inode on server without sha256sum");
-        return await this.storage.read(inode.sha256sum, 0, inode.size);
+        return await this.storage.read(inode.sha256sum, 0, inode.size, inode.size);
     }
     else
     {
@@ -1095,7 +1095,7 @@ FS.prototype.get_data = async function(idx, offset, count)
     else if(inode.status === STATUS_ON_STORAGE)
     {
         dbg_assert(inode.sha256sum, "Filesystem get_data: found inode on server without sha256sum");
-        return await this.storage.read(inode.sha256sum, offset, count);
+        return await this.storage.read(inode.sha256sum, offset, count, inode.size);
     }
     else
     {
diff --git a/src/browser/filestorage.js b/src/browser/filestorage.js
index c84c7c11..7ce76c80 100644
--- a/src/browser/filestorage.js
+++ b/src/browser/filestorage.js
@@ -9,9 +9,10 @@ export function FileStorageInterface() {}
  * @param {string} sha256sum
  * @param {number} offset
  * @param {number} count
+ * @param {number} file_size
  * @return {!Promise<Uint8Array>} null if file does not exist.
  */
-FileStorageInterface.prototype.read = function(sha256sum, offset, count) {};
+FileStorageInterface.prototype.read = function(sha256sum, offset, count, file_size) {};
 
 /**
  * Add a read-only file to the filestorage.
@@ -83,8 +84,9 @@ MemoryFileStorage.prototype.uncache = function(sha256sum)
  * @implements {FileStorageInterface}
  * @param {FileStorageInterface} file_storage
  * @param {string} baseurl
+ * @param {function(number,Uint8Array):ArrayBuffer} zstd_decompress
  */
-export function ServerFileStorageWrapper(file_storage, baseurl)
+export function ServerFileStorageWrapper(file_storage, baseurl, zstd_decompress)
 {
     dbg_assert(baseurl, "ServerMemoryFileStorage: baseurl should not be empty");
 
@@ -95,19 +97,26 @@ export function ServerFileStorageWrapper(file_storage, baseurl)
 
     this.storage = file_storage;
     this.baseurl = baseurl;
+    this.zstd_decompress = zstd_decompress;
 }
 
 /**
  * @param {string} sha256sum
+ * @param {number} file_size
  * @return {!Promise<Uint8Array>}
  */
-ServerFileStorageWrapper.prototype.load_from_server = function(sha256sum)
+ServerFileStorageWrapper.prototype.load_from_server = function(sha256sum, file_size)
 {
     return new Promise((resolve, reject) =>
     {
         load_file(this.baseurl + sha256sum, { done: async buffer =>
         {
-            const data = new Uint8Array(buffer);
+            let data = new Uint8Array(buffer);
+            if (sha256sum.endsWith('.zst')) {
+                data = new Uint8Array(
+                    this.zstd_decompress(file_size, data)
+                );
+            }
             await this.cache(sha256sum, data);
             resolve(data);
         }});
@@ -118,14 +127,15 @@ ServerFileStorageWrapper.prototype.load_from_server = function(sha256sum)
  * @param {string} sha256sum
  * @param {number} offset
  * @param {number} count
+ * @param {number} file_size
  * @return {!Promise<Uint8Array>}
  */
-ServerFileStorageWrapper.prototype.read = async function(sha256sum, offset, count)
+ServerFileStorageWrapper.prototype.read = async function(sha256sum, offset, count, file_size)
 {
     const data = await this.storage.read(sha256sum, offset, count);
     if(!data)
     {
-        const full_file = await this.load_from_server(sha256sum);
+        const full_file = await this.load_from_server(sha256sum, file_size);
         return full_file.subarray(offset, offset + count);
     }
     return data;
diff --git a/src/browser/starter.js b/src/browser/starter.js
index 87b66859..103f2199 100644
--- a/src/browser/starter.js
+++ b/src/browser/starter.js
@@ -436,7 +436,7 @@ V86.prototype.continue_init = async function(emulator, options)
 
         if(base_url)
         {
-            file_storage = new ServerFileStorageWrapper(file_storage, base_url);
+            file_storage = new ServerFileStorageWrapper(file_storage, base_url, this.zstd_decompress);
         }
         settings.fs9p = this.fs9p = new FS(file_storage);