authorgravatar for squeek502@hotmail.comRyan Liptak <squeek502@hotmail.com> 2025-12-20 20:15:14-08:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2025-12-23 22:15:11-08:00
logad08117e9daf5d2a34be1ca71a23366f39079990
treec44d26a0a774c047a853542da3c2ba0bb9a771f4
parentfd0c324cb05d0d30f8ca5ae44f6db5072975b125

Fix sizing of buffer/reservation size for dirReadWindows

2 files changed, 11 insertions(+), 4 deletions(-)

lib/std/Io/Dir.zig+6-1
......@@ -105,7 +105,12 @@ pub const Reader = struct {
105105 pub const min_buffer_len = switch (native_os) {
106106 .linux => std.mem.alignForward(usize, @sizeOf(std.os.linux.dirent64), 8) +
107107 std.mem.alignForward(usize, max_name_bytes, 8),
108 .windows => std.mem.alignForward(usize, max_name_bytes, @alignOf(usize)),
108 .windows => len: {
109 const max_info_len = @sizeOf(std.os.windows.FILE_BOTH_DIR_INFORMATION) + std.os.windows.NAME_MAX * 2;
110 const info_align = @alignOf(std.os.windows.FILE_BOTH_DIR_INFORMATION);
111 const reserved_len = std.mem.alignForward(usize, max_name_bytes, info_align) - max_info_len;
112 break :len std.mem.alignForward(usize, reserved_len, info_align) + max_info_len;
113 },
109114 .wasi => @sizeOf(std.os.wasi.dirent_t) +
110115 std.mem.alignForward(usize, max_name_bytes, @alignOf(std.os.wasi.dirent_t)),
111116 else => if (builtin.link_libc) @sizeOf(std.c.dirent) else std.mem.alignForward(usize, max_name_bytes, @alignOf(usize)),
lib/std/Io/Threaded.zig+5-3
......@@ -3757,11 +3757,13 @@ fn dirReadWindows(userdata: ?*anyopaque, dr: *Dir.Reader, buffer: []Dir.Entry) D
37573757 // reserve enough to get us to up to having `3 * NAME_MAX` bytes available when taking into account
37583758 // that we have the ability to write over top of the reserved memory + the full footprint of that
37593759 // particular `FILE_BOTH_DIR_INFORMATION`.
3760 const reserve_needed = w.NAME_MAX - @sizeOf(w.FILE_BOTH_DIR_INFORMATION);
3761 const unreserved_start = std.mem.alignForward(usize, reserve_needed, @alignOf(usize));
3760 const max_info_len = @sizeOf(w.FILE_BOTH_DIR_INFORMATION) + w.NAME_MAX * 2;
3761 const info_align = @alignOf(w.FILE_BOTH_DIR_INFORMATION);
3762 const reserve_needed = std.mem.alignForward(usize, Dir.max_name_bytes, info_align) - max_info_len;
3763 const unreserved_start = std.mem.alignForward(usize, reserve_needed, info_align);
37623764 const unreserved_buffer = dr.buffer[unreserved_start..];
37633765 // This is enforced by `Dir.Reader`
3764 assert(unreserved_buffer.len >= @sizeOf(w.FILE_BOTH_DIR_INFORMATION) + w.NAME_MAX * 2);
3766 assert(unreserved_buffer.len >= max_info_len);
37653767
37663768 var name_index: usize = 0;
37673769 var buffer_index: usize = 0;