From 7974576967157aede2beff8c960d18685d7d5b6d Mon Sep 17 00:00:00 2001
From: Linus Groh <mail@linusgroh.de>
Date: Sat, 20 Apr 2024 17:14:35 +0100
Subject: [PATCH] std.fs.Dir.openDir: use wasi libc API when -lc

Same as #19680 but for directories.
---
 lib/std/fs/Dir.zig | 45 +++++++++++++++++++++++++++------------------
 1 file changed, 27 insertions(+), 18 deletions(-)

diff --git a/lib/std/fs/Dir.zig b/lib/std/fs/Dir.zig
index 89b1d18b9c..bd0a8fe4e8 100644
--- a/lib/std/fs/Dir.zig
+++ b/lib/std/fs/Dir.zig
@@ -1401,7 +1401,7 @@ pub fn openDir(self: Dir, sub_path: []const u8, args: OpenDirOptions) OpenError!
             const sub_path_w = try windows.sliceToPrefixedFileW(self.fd, sub_path);
             return self.openDirW(sub_path_w.span().ptr, args);
         },
-        .wasi => {
+        .wasi => if (!builtin.link_libc) {
             var base: std.os.wasi.rights_t = .{
                 .FD_FILESTAT_GET = true,
                 .FD_FDSTAT_SET_FLAGS = true,
@@ -1446,11 +1446,10 @@ pub fn openDir(self: Dir, sub_path: []const u8, args: OpenDirOptions) OpenError!
             };
             return .{ .fd = fd };
         },
-        else => {
-            const sub_path_c = try posix.toPosixPath(sub_path);
-            return self.openDirZ(&sub_path_c, args);
-        },
+        else => {},
     }
+    const sub_path_c = try posix.toPosixPath(sub_path);
+    return self.openDirZ(&sub_path_c, args);
 }
 
 /// Same as `openDir` except the parameter is null-terminated.
@@ -1460,7 +1459,9 @@ pub fn openDirZ(self: Dir, sub_path_c: [*:0]const u8, args: OpenDirOptions) Open
             const sub_path_w = try windows.cStrToPrefixedFileW(self.fd, sub_path_c);
             return self.openDirW(sub_path_w.span().ptr, args);
         },
-        .wasi => {
+        // Use the libc API when libc is linked because it implements things
+        // such as opening absolute directory paths.
+        .wasi => if (!builtin.link_libc) {
             return openDir(self, mem.sliceTo(sub_path_c, 0), args);
         },
         .haiku => {
@@ -1484,19 +1485,27 @@ pub fn openDirZ(self: Dir, sub_path_c: [*:0]const u8, args: OpenDirOptions) Open
                 else => |err| return posix.unexpectedErrno(err),
             }
         },
-        else => {
-            var symlink_flags: posix.O = .{
-                .ACCMODE = .RDONLY,
-                .NOFOLLOW = args.no_follow,
-                .DIRECTORY = true,
-                .CLOEXEC = true,
-            };
-            if (@hasField(posix.O, "PATH") and !args.iterate)
-                symlink_flags.PATH = true;
-
-            return self.openDirFlagsZ(sub_path_c, symlink_flags);
-        },
+        else => {},
     }
+
+    var symlink_flags: posix.O = switch (native_os) {
+        .wasi => .{
+            .read = true,
+            .NOFOLLOW = args.no_follow,
+            .DIRECTORY = true,
+        },
+        else => .{
+            .ACCMODE = .RDONLY,
+            .NOFOLLOW = args.no_follow,
+            .DIRECTORY = true,
+            .CLOEXEC = true,
+        },
+    };
+
+    if (@hasField(posix.O, "PATH") and !args.iterate)
+        symlink_flags.PATH = true;
+
+    return self.openDirFlagsZ(sub_path_c, symlink_flags);
 }
 
 /// Same as `openDir` except the path parameter is WTF-16 LE encoded, NT-prefixed.