[Patch] Encode invalid chars in /proc/registry entries

Christian Franke Christian.Franke@t-online.de
Thu Nov 15 21:57:00 GMT 2007

Registry key and value names may contain chars which are not allowed 
within file names ('/', '\', ":"). But Cygwin's /proc/registry returns 
these names unchanged to the app. The obvious effect is that such 
entries cannot be accessed.

But if an entry name is identical to an existing path, more interesting 
results occur. Cygwin itself adds registry entries which are testcases 
for this issue :-))

An app that descends dirs by chdir() continues outside of /proc/registry 
and may finally re-enter /proc/registry:

$ find /proc/registry/HKEY_LOCAL_MACHINE/SOFTWARE/Cygnus Solutions/
/proc/registry/.../Cygnus Solutions/Cygwin/
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//bin
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//bin/822-date
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//bin/a2p.exe
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//bin/aclocal-1.10
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//bin/znew
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//proc/registry/...

If an app descends by path concatenation (like ncdu), infinite recursion 
may occur if entry name is "/":

/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2////
/proc/registry/.../Cygnus Solutions/Cygwin/mounts v2//////

The attached patch encodes the critical chars with %XX to avoid such 

Patch is tested with 1.5.24-2. Merge with HEAD looks good, but was not 
actually tested. Therefore, no changelog provided yet.


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