zig

commit 6d74c0d1b41b52bca3d66092a48660f2ee4ae4f8 (tree)
parent e3cf9d165081533524927cebf8a92ac6fee097f2
Author: Ryan Liptak <squeek502@hotmail.com>
Date:   Wed,  8 Mar 2023 00:57:39 -0800

Add comments explaining BUFFER_OVERFLOW during NtQueryInformationFile calls

Diffstat:
M
lib/std/fs/file.zig
 | 
6
++++++

1 file changed, 6 insertions(+), 0 deletions(-)
diff --git a/lib/std/fs/file.zig b/lib/std/fs/file.zig
@@ -379,6 +379,9 @@ pub const File = struct {
             const rc = windows.ntdll.NtQueryInformationFile(self.handle, &io_status_block, &info, @sizeOf(windows.FILE_ALL_INFORMATION), .FileAllInformation);
             switch (rc) {
                 .SUCCESS => {},
+                // Buffer overflow here indicates that there is more information available than was able to be stored in the buffer
+                // size provided. This is treated as success because the type of variable-length information that this would be relevant for
+                // (name, volume name, etc) we don't care about.
                 .BUFFER_OVERFLOW => {},
                 .INVALID_PARAMETER => unreachable,
                 .ACCESS_DENIED => return error.AccessDenied,
@@ -830,6 +833,9 @@ pub const File = struct {
                     const rc = windows.ntdll.NtQueryInformationFile(self.handle, &io_status_block, &info, @sizeOf(windows.FILE_ALL_INFORMATION), .FileAllInformation);
                     switch (rc) {
                         .SUCCESS => {},
+                        // Buffer overflow here indicates that there is more information available than was able to be stored in the buffer
+                        // size provided. This is treated as success because the type of variable-length information that this would be relevant for
+                        // (name, volume name, etc) we don't care about.
                         .BUFFER_OVERFLOW => {},
                         .INVALID_PARAMETER => unreachable,
                         .ACCESS_DENIED => return error.AccessDenied,