On Thu, 21 May 2026 22:53:09 GMT, Ashay Rane <[email protected]> wrote:
>> Although the original implementation of `JLI_Open()` borrowed from the >> code in src/hotspot/os/windows/os_windows.cpp, the improvements to >> os_windows.cpp don't seem to have been applied to java_md.c, causing >> some tests to fail when the path to JAR files is longer than `MAXPATH` >> (i.e. 260) characters on Windows (see associated JBS issue 8385024 for >> details). Since `JLI_Open()` is not just invoked inside tests, this is >> not a test-specific issue, so fixing the test is not the right solution. >> >> This patch applies the recent changes from os_windows.cpp to java_md.c >> so that `JLI_Open()` can correctly handle longer than `MAXPATH` paths. >> The new code is almost the same as that in `wide_abs_unc_path()` in >> os_windows.cpp, except that the code in java_md.c uses `JLI_MemAlloc()` >> and `JLI_MemFree()` for memory allocation and deallocation. >> >> Although it would be ideal to have just one implementation between >> HotSpot and the launcher, the dependencies of the two components >> prevents us from having a single implementation. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Ashay Rane has updated the pull request incrementally with one additional > commit since the last revision: > > Address PR comments > > 1. Optimize for the common case when the JAR path is shorter than > `MAX_PATH` by using a stack buffer of size length `MAX_PATH`. If the > full path is longer than that, then we allocate a heap buffer of the > desired size before calling `GetFullPathNameW()` with a buffer of the > right size. > > 2. Normalize the path before called `set_path_prefix()`, just like in > os_windows.cpp. This ensures that prefixed paths with forward > slashes work correctly. > > 3. Renamed `create_unc_path()` to `convert_to_absolute_path()` to > reflect the common action performed by the function. > > 4. Dropped the accidental overwritting of `errno` after calling > `_wopen()`. That's unfortunate, but understandable. I tried working around the Java code using this: ProcessBuilder pb = new ProcessBuilder( "cmd", "/c", "cd /d "\\\?\" + absDir + "" && "" + javaCmd + "" -jar elp.jar" ); but sadly, cmd's `cd` doesn't support UNC paths for setting the current directory: C:\>cd \?\C:\ '\?\C:' CMD does not support UNC paths as current directories. ------------- PR Comment: https://git.openjdk.org/jdk/pull/31209#issuecomment-4522347956
