From 62adfbc2d220412a3772b3b93b218d13577060bc Mon Sep 17 00:00:00 2001
From: Michael Chiu <m_chiu@apple.com>
Date: Wed, 15 Jan 2025 04:09:34 -0800
Subject: [PATCH] Fix FreeBSD build

---
 .../FileManager/FileOperations.swift          | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/Sources/FoundationEssentials/FileManager/FileOperations.swift b/Sources/FoundationEssentials/FileManager/FileOperations.swift
index 62503c95..668d2c6e 100644
--- a/Sources/FoundationEssentials/FileManager/FileOperations.swift
+++ b/Sources/FoundationEssentials/FileManager/FileOperations.swift
@@ -960,6 +960,45 @@ enum _FileOperations {
     private static func _copyDirectoryMetadata(srcFD: CInt, srcPath: @autoclosure () -> String, dstFD: CInt, dstPath: @autoclosure () -> String, delegate: some LinkOrCopyDelegate) throws {
         #if !os(WASI) && !os(Android)
         // Copy extended attributes
+        #if os(FreeBSD)
+        // FreeBSD uses the `extattr_*` calls for setting extended attributes. Unlike like, the namespace for the extattrs are not determined by prefix of the attribute
+        for namespace in [EXTATTR_NAMESPACE_SYSTEM, EXTATTR_NAMESPACE_USER] {
+            // if we don't have permission to list attributes in system namespace, this returns -1 and skips it
+            var size = extattr_list_fd(srcFD, namespace, nil, 0)
+            if size > 0 {
+                try withUnsafeTemporaryAllocation(of: CChar.self, capacity: size + 1) { keyList in
+                    // The list of entry returns by `extattr_list_*` contains the length(1 byte) of the attribute name, follow by the Non-NULL terminated attribute name. (See exattr(2))
+                    size = extattr_list_fd(srcFD, namespace, keyList.baseAddress!, size)
+                    var keyLength = Int(keyList.baseAddress!.pointee)
+                    var current = keyList.baseAddress!.advanced(by: 1)
+                    let end = keyList.baseAddress!.advanced(by: keyList.count)
+                    keyList.baseAddress!.advanced(by: size).pointee = 0
+
+                    while current < end {
+                        let nextEntry = current.advanced(by: keyLength)
+                        // get the length of next key, if this is the last entry, this points to the explicitly zerod byte at `end`.
+                        keyLength = Int(nextEntry.pointee)
+                        // zero the length field of the next name, so current name can pass in as a null-terminated string
+                        nextEntry.pointee = 0
+                        // this also set `current` to `end` after iterating all entries
+                        defer { current = nextEntry.advanced(by: 1) }
+
+                        var valueSize = extattr_get_fd(srcFD, namespace, current, nil, 0)
+                        if valueSize >= 0 {
+                            try withUnsafeTemporaryAllocation(of: UInt8.self, capacity: valueSize) { valueBuffer in
+                                valueSize = extattr_get_fd(srcFD, namespace, current, valueBuffer.baseAddress!, valueSize)
+                                if valueSize >= 0 {
+                                    if extattr_set_fd(srcFD, namespace, current, valueBuffer.baseAddress!, valueSize) != 0 {
+                                        try delegate.throwIfNecessary(errno, srcPath(), dstPath())
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        #else
         var size = flistxattr(srcFD, nil, 0)
         if size > 0 {
             try withUnsafeTemporaryAllocation(of: CChar.self, capacity: size) { keyList in
@@ -985,6 +1024,7 @@ enum _FileOperations {
             }
         }
         #endif
+        #endif
         var statInfo = stat()
         if fstat(srcFD, &statInfo) == 0 {
             #if !os(WASI) // WASI doesn't have fchown for now