[newlib-cygwin] Cygwin: return correct FH_PROCESSFD for files under /proc/PID/fd subdir

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=f72191ac0177883bb395d8d5f0ddc3f45b5dd29d

commit f72191ac0177883bb395d8d5f0ddc3f45b5dd29d
Author: Corinna Vinschen <corinna@vinschen.de>
Date:   Sat Jan 5 21:36:34 2019 +0100

    Cygwin: return correct FH_PROCESSFD for files under /proc/PID/fd subdir
    
    This allows easier handling of fd symlinks.
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/fhandler_proc.cc | 12 ++++++++++--
 winsup/cygwin/path.cc          |  2 +-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/winsup/cygwin/fhandler_proc.cc b/winsup/cygwin/fhandler_proc.cc
index c9761b5..cda2f72 100644
--- a/winsup/cygwin/fhandler_proc.cc
+++ b/winsup/cygwin/fhandler_proc.cc
@@ -134,14 +134,22 @@ fhandler_proc::get_proc_fhandler (const char *path)
   if (entry)
     return entry->fhandler;
 
-  int pid = atoi (path);
+  char *e;
+  pid_t pid = strtoul (path, &e, 10);
+  if (*e != '/' && *e != '\0')
+    return FH_NADA;
   pinfo p (pid);
   /* If p->pid != pid, then pid is actually the Windows PID for an execed
      Cygwin process, and the pinfo entry is the additional entry created
      at exec time.  We don't want to enable the user to access a process
      entry by using the Win32 PID, though. */
   if (p && p->pid == pid)
-    return FH_PROCESS;
+    {
+      /* Check for entry in fd subdir */
+      if (!strncmp (++e, "fd/", 3) && e[3] != '\0')
+	return FH_PROCESSFD;
+      return FH_PROCESS;
+    }
 
   bool has_subdir = false;
   while (*path)
diff --git a/winsup/cygwin/path.cc b/winsup/cygwin/path.cc
index ee15dec..3324395 100644
--- a/winsup/cygwin/path.cc
+++ b/winsup/cygwin/path.cc
@@ -806,7 +806,7 @@ path_conv::check (const char *src, unsigned opt,
 			  fh->fill_filebuf ();
 			  symlen = sym.set (fh->get_filebuf ());
 			}
-		      else if (file_type == virt_fsdir && dev == FH_PROCESS)
+		      else if (file_type == virt_fsdir && dev == FH_PROCESSFD)
 			{
 			  /* FIXME: This is YA bad hack to workaround that
 			     we're checking for isvirtual_dev at this point.