From 7dc7b866b110a9a4831221c304f7dda00ccaeb93 Mon Sep 17 00:00:00 2001
From: Whindmar Saksit <whindsaks@proton.me>
Date: Thu, 20 Mar 2025 14:32:07 +0100
Subject: [PATCH] [RAPPS] Don't delete downloaded ZIP/CAB even if configured to
 (#7791)

---
 base/applications/rapps/geninst.cpp    | 13 ++++++-
 base/applications/rapps/include/misc.h |  4 ++
 base/applications/rapps/loaddlg.cpp    |  9 ++++-
 base/applications/rapps/misc.cpp       | 53 ++++++++++++++++++++++++++
 base/applications/rapps/winmain.cpp    |  2 +-
 5 files changed, 78 insertions(+), 3 deletions(-)

diff --git a/base/applications/rapps/geninst.cpp b/base/applications/rapps/geninst.cpp
index d5746d5199a..9d00156f55c 100644
--- a/base/applications/rapps/geninst.cpp
+++ b/base/applications/rapps/geninst.cpp
@@ -47,6 +47,17 @@ enum {
     UNOP_EMPTYREGKEY = 'k',
 };
 
+BOOL IsZipFile(PCWSTR Path)
+{
+    zlib_filefunc64_def zff;
+    fill_win32_filefunc64W(&zff);
+    unzFile hzf = unzOpen2_64(Path, &zff);
+    if (!hzf)
+        return FALSE;
+    unzClose(hzf);
+    return TRUE;
+}
+
 static int
 ExtractFilesFromZip(LPCWSTR Archive, const CStringW &OutputDir,
                     EXTRACTCALLBACK Callback, void *Cookie)
@@ -491,7 +502,7 @@ ExtractAndInstallThread(LPVOID Parameter)
 
     if (!Info.Error)
     {
-        BOOL isCab = SplitFileAndDirectory(Archive).Right(4).CompareNoCase(L".cab") == 0;
+        BOOL isCab = LOBYTE(ClassifyFile(tempdir)) == 'C';
         Info.Error = isCab ? ExtractCab(Archive, tempdir, ExtractCallback, &Info)
                            : ExtractZip(Archive, tempdir, ExtractCallback, &Info);
     }
diff --git a/base/applications/rapps/include/misc.h b/base/applications/rapps/include/misc.h
index 6e8b56ffb14..6e7814b8cee 100644
--- a/base/applications/rapps/include/misc.h
+++ b/base/applications/rapps/include/misc.h
@@ -35,6 +35,10 @@ VOID
 ShowPopupMenuEx(HWND hwnd, HWND hwndOwner, UINT MenuID, UINT DefaultItem, POINT *Point = NULL);
 VOID
 EmulateDialogReposition(HWND hwnd);
+UINT
+ClassifyFile(PCWSTR Path);
+BOOL
+OpensWithExplorer(PCWSTR Path);
 BOOL
 StartProcess(const CStringW &Path, BOOL Wait);
 BOOL
diff --git a/base/applications/rapps/loaddlg.cpp b/base/applications/rapps/loaddlg.cpp
index 21b7b88d1fc..8d51fe78f8c 100644
--- a/base/applications/rapps/loaddlg.cpp
+++ b/base/applications/rapps/loaddlg.cpp
@@ -1115,7 +1115,14 @@ end:
     if (bTempfile)
     {
         if (bCancelled || (SettingsInfo.bDelInstaller && Info.DLType == DLTYPE_APPLICATION))
-            DeleteFileW(Path);
+        {
+            // Don't delete .zip/.cab files so the user can extract from them
+            if (bCancelled || Info.IType == INSTALLER_GENERATE || !OpensWithExplorer(Path) ||
+                HIBYTE(ClassifyFile(Path)) != PERCEIVED_TYPE_COMPRESSED)
+            {
+                DeleteFileW(Path);
+            }
+        }
     }
 
     SendMessageW(hDlg, WM_SETSTATUS, DLSTATUS_FINISHED, 0);
diff --git a/base/applications/rapps/misc.cpp b/base/applications/rapps/misc.cpp
index e8d9e439177..0965cc945d0 100644
--- a/base/applications/rapps/misc.cpp
+++ b/base/applications/rapps/misc.cpp
@@ -119,6 +119,59 @@ ShowPopupMenuEx(HWND hwnd, HWND hwndOwner, UINT MenuID, UINT DefaultItem, POINT
     }
 }
 
+extern BOOL IsZipFile(PCWSTR Path);
+
+UINT
+ClassifyFile(PCWSTR Path)
+{
+    const UINT share = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
+    HANDLE hFile = CreateFileW(Path, GENERIC_READ, share, NULL, OPEN_EXISTING, 0, NULL);
+    if (hFile != INVALID_HANDLE_VALUE)
+    {
+        BYTE buf[8];
+        DWORD io;
+        if (!ReadFile(hFile, buf, sizeof(buf), &io, NULL) || io != sizeof(buf))
+            buf[0] = 0;
+        CloseHandle(hFile);
+
+        if (buf[0] == 0xD0 && buf[1] == 0xCF && buf[2] == 0x11 && buf[3] == 0xE0 &&
+            buf[4] == 0xA1 && buf[5] == 0xB1 && buf[6] == 0x1A && buf[7] == 0xE1)
+        {
+            return MAKEWORD('M', PERCEIVED_TYPE_APPLICATION); // MSI
+        }
+        if (buf[0] == 'M' || buf[0] == 'Z')
+        {
+            SHFILEINFO shfi;
+            if (SHGetFileInfoW(Path, 0, &shfi, sizeof(shfi), SHGFI_EXETYPE))
+                return MAKEWORD('E', PERCEIVED_TYPE_APPLICATION);
+        }
+        if (buf[0] == 'M' && buf[1] == 'S' && buf[2] == 'C' && buf[3] == 'F')
+        {
+            return MAKEWORD('C', PERCEIVED_TYPE_COMPRESSED); // CAB
+        }
+    }
+
+    if (IsZipFile(Path)) // .zip last because we want to return SFX.exe with higher priority
+    {
+        return MAKEWORD('Z', PERCEIVED_TYPE_COMPRESSED);
+    }
+    return PERCEIVED_TYPE_UNKNOWN;
+}
+
+BOOL
+OpensWithExplorer(PCWSTR Path)
+{
+    WCHAR szCmd[MAX_PATH * 2];
+    DWORD cch = _countof(szCmd);
+    PCWSTR pszExt = PathFindExtensionW(Path);
+    HRESULT hr = AssocQueryStringW(ASSOCF_INIT_IGNOREUNKNOWN | ASSOCF_NOTRUNCATE,
+                                   ASSOCSTR_COMMAND, pszExt, NULL, szCmd, &cch);
+    if (SUCCEEDED(hr) && StrStrIW(szCmd, L" zipfldr.dll,")) // .zip
+        return TRUE;
+    PathRemoveArgsW(szCmd);
+    return SUCCEEDED(hr) && !StrCmpIW(PathFindFileNameW(szCmd), L"explorer.exe"); // .cab
+}
+
 BOOL
 StartProcess(const CStringW &Path, BOOL Wait)
 {
diff --git a/base/applications/rapps/winmain.cpp b/base/applications/rapps/winmain.cpp
index 70ce317a468..e36ac0db5ab 100644
--- a/base/applications/rapps/winmain.cpp
+++ b/base/applications/rapps/winmain.cpp
@@ -16,7 +16,7 @@
 LPCWSTR szWindowClass = MAINWINDOWCLASSNAME;
 LONG g_Busy = 0;
 
-HWND hMainWnd;
+HWND hMainWnd = NULL;
 HINSTANCE hInst;
 SETTINGS_INFO SettingsInfo;