From 7a8ef52408456617aa8442bb2adf7a795687efc5 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sat, 20 May 2023 21:48:18 +0200
Subject: [PATCH] libos: Support not following symlinks

---
 libos/include/os/FileSystem.h |  6 +++---
 libos/src/FileSystem.cpp      | 13 +++++++------
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/libos/include/os/FileSystem.h b/libos/include/os/FileSystem.h
index 029519e6..26653af8 100644
--- a/libos/include/os/FileSystem.h
+++ b/libos/include/os/FileSystem.h
@@ -9,11 +9,11 @@ namespace os
 {
     namespace FileSystem
     {
-        bool exists(const Path& path);
+        bool exists(const Path& path, bool follow_symlinks = true);
 
-        bool is_directory(const Path& path);
+        bool is_directory(const Path& path, bool follow_symlinks = false);
 
-        Result<void> stat(const Path& path, struct stat& st);
+        Result<void> stat(const Path& path, struct stat& st, bool follow_symlinks = true);
 
         Result<void> create_directory(StringView path, mode_t mode);
 
diff --git a/libos/src/FileSystem.cpp b/libos/src/FileSystem.cpp
index e82716c1..bf7b2dc2 100644
--- a/libos/src/FileSystem.cpp
+++ b/libos/src/FileSystem.cpp
@@ -12,28 +12,29 @@
 
 namespace os::FileSystem
 {
-    bool exists(const Path& path)
+    bool exists(const Path& path, bool follow_symlinks)
     {
         struct stat st;
 
-        if (stat(path, st).has_error()) return false;
+        if (stat(path, st, follow_symlinks).has_error()) return false;
 
         return true;
     }
 
-    bool is_directory(const Path& path)
+    bool is_directory(const Path& path, bool follow_symlinks)
     {
         struct stat st;
 
-        if (stat(path, st).has_error()) return false;
+        if (stat(path, st, follow_symlinks).has_error()) return false;
 
         return S_ISDIR(st.st_mode);
     }
 
-    Result<void> stat(const Path& path, struct stat& st)
+    Result<void> stat(const Path& path, struct stat& st, bool follow_symlinks)
     {
         long rc =
-            syscall(SYS_fstatat, path.dirfd(), path.name().chars(), &st, path.is_empty_path() ? AT_EMPTY_PATH : 0);
+            syscall(SYS_fstatat, path.dirfd(), path.name().chars(), &st,
+                    (int)((path.is_empty_path() ? AT_EMPTY_PATH : 0) | (follow_symlinks ? 0 : AT_SYMLINK_NOFOLLOW)));
 
         return Result<void>::from_syscall(rc);
     }