[Bug 59272] New: COM ports resolved relative to working directory instead of dosdevices

[WineHQ Bugzilla]

http://bugs.winehq.org/show_bug.cgi?id=59272

            Bug ID: 59272
           Summary: COM ports resolved relative to working directory
                    instead of dosdevices
           Product: Wine
           Version: unspecified
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: major
          Priority: P2
         Component: kernel32
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Wine incorrectly resolves COM port paths relative to the current working
directory instead of using the symlinks in ~/.wine/dosdevices/, causing
CreateFile() calls for COM ports to fail when the application is launched from
subdirectories.

STEPS TO REPRODUCE:
1. Create a symlink in dosdevices:
   ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1

2. Create a test application that calls:
   CreateFile("COM1", GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0,
NULL);

3. Run the application from C:\:
   cd ~/.wine/drive_c/
   wine test.exe
   Result: COM1 opens successfully via /dev/ttyUSB0

4. Run the application from a subdirectory:
   cd ~/.wine/drive_c/subdir/
   wine test.exe
   Result: CreateFile fails with ERROR_FILE_NOT_FOUND

EXPECTED BEHAVIOR:
COM ports should always resolve through dosdevices symlinks regardless of
working directory, matching Windows behavior where COM1 is a global device
namespace.

ACTUAL BEHAVIOR:
Wine attempts to open "C:\subdir\COM1" as a regular file instead of resolving
COM1 through dosdevices.

DEBUG TRACE:
trace:file:CreateFileW L"COM1" GENERIC_READ GENERIC_WRITE creation 3 attributes
0x0
trace:file:NtCreateFile name=L"\\??\\C:\\subdir\\COM1"
warn:file:NtCreateFile L"\\??\\C:\\subdir\\COM1" not found (c0000034)

WORKAROUND:
Creating a symlink directly in the working directory allows the application to
open the port, but this is not portable and breaks when changing directories:
ln -s /dev/ttyUSB0 ~/.wine/drive_c/subdir/COM1

ADDITIONAL NOTES:
This affects serial communication applications that rely on standard COM port
naming conventions. The issue appears to be in how Wine's file path resolution
handles device names. On real Windows, device names like COM1, LPT1, etc. are
resolved through the device namespace regardless of the current directory.

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