* fhandler.h (class fhandler_process): Add fd_type member.

	* fhandler_process.cc (process_tab): Fix indentation.
	(fhandler_process::exists): Rely on format_process_fd returning file
	type in fd_type.
	(struct process_fd_t): Add fd_type member.
	(fhandler_process::fill_filebuf): Allow format_process_fd to set
	this->fd_type member.
	(format_process_fd): Fix path evaluation to allow recognizing trailing
	path components.  Fix check for file descriptor path component.  Return
	virt_symlink in fd_type if no trailing path compenents exist, return
	virt_fsdir otherwise and copy full resulting path into destbuf.
	* path.cc (path_conv::check): If /proc/$PID/fd symlink has trailing
	path components, reparse resulting path as if it's the incoming path.
	Add comment to wail over the outdated and hackish check method, and to
	explain what we do here.

1 files changed, 29 insertions, 10 deletions

diff --git a/winsup/cygwin/fhandler_process.cc b/winsup/cygwin/fhandler_process.cc
index e2de05b3c..161050b3b 100644
--- a/winsup/cygwin/fhandler_process.cc
+++ b/winsup/cygwin/fhandler_process.cc
@@ -1,7 +1,7 @@
 /* fhandler_process.cc: fhandler for /proc/<pid> virtual filesystem
 
    Copyright 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012,
-   2013, 2014 Red Hat, Inc.
+   2013, 2014, 2015 Red Hat, Inc.
 
 This file is part of Cygwin.
 
@@ -77,7 +77,7 @@ static const virt_tab_t process_tab[] =
   { _VN ("uid"),        FH_PROCESS,   virt_file,      format_process_uid },
   { _VN ("winexename"), FH_PROCESS,   virt_file,      format_process_winexename },
   { _VN ("winpid"),     FH_PROCESS,   virt_file,      format_process_winpid },
-  { NULL, 0,	        FH_NADA,       virt_none,      NULL }
+  { NULL, 0,	        FH_NADA,      virt_none,      NULL }
 };
 
 static const int PROCESS_LINK_COUNT =
@@ -111,11 +111,11 @@ fhandler_process::exists ()
 	  fileid = entry - process_tab;
 	  return entry->type;
 	}
-      if (entry->type == virt_directory)
+      if (entry->type == virt_directory)	/* fd subdir only */
 	{
 	  fileid = entry - process_tab;
 	  if (fill_filebuf ())
-	    return virt_symlink;
+	    return fd_type;
 	  /* Check for nameless device entries. */
 	  path = strrchr (path, '/');
 	  if (path && *++path)
@@ -325,6 +325,7 @@ out:
 struct process_fd_t {
   const char *path;
   _pinfo *p;
+  virtual_ftype_t *fd_type;
 };
 
 bool
@@ -350,7 +351,7 @@ fhandler_process::fill_filebuf ()
     {
       if (process_tab[fileid].fhandler == FH_PROCESSFD)
 	{
-	  process_fd_t fd = { path, p };
+	  process_fd_t fd = { path, p , &fd_type };
 	  filesize = process_tab[fileid].format_func (&fd, filebuf);
 	}
       else
@@ -366,20 +367,27 @@ format_process_fd (void *data, char *&destbuf)
   _pinfo *p = ((process_fd_t *) data)->p;
   const char *path = ((process_fd_t *) data)->path;
   size_t fs = 0;
-  char *fdp = strrchr (path, '/');
-
-  if (!fdp || *++fdp == 'f') /* The "fd" directory itself. */
+  /* path looks like "$PID/fd", "$PID/fd/", "$PID/fd/[0-9]*".  In the latter
+     case a trailing slash and more followup chars are allowed, provided the
+     descriptor symlink points to a directory. */
+  char *fdp = strchr (path, '/') + 3;
+  /* The "fd" directory itself? */
+  if (fdp[0] =='\0' || (fdp[0] == '/' && fdp[1] == '\0'))
     {
       if (destbuf)
 	cfree (destbuf);
       destbuf = p->fds (fs);
+      *((process_fd_t *) data)->fd_type = virt_symlink;
     }
   else
     {
+      char *e;
+      int fd;
+
       if (destbuf)
 	cfree (destbuf);
-      int fd = atoi (fdp);
-      if (fd < 0 || (fd == 0 && !isdigit (*fdp)))
+      fd = strtol (++fdp, &e, 10);
+      if (fd < 0 || e == fdp || (*e != '/' && *e != '\0'))
 	{
 	  set_errno (ENOENT);
 	  return 0;
@@ -390,6 +398,17 @@ format_process_fd (void *data, char *&destbuf)
 	  set_errno (ENOENT);
 	  return 0;
 	}
+      if (*e == '\0')
+	*((process_fd_t *) data)->fd_type = virt_symlink;
+      else /* trailing path */
+	{
+	  char *newbuf = (char *) cmalloc_abort (HEAP_STR, strlen (destbuf)
+							   + strlen (e) + 1);
+	  stpcpy (stpcpy (newbuf, destbuf), e);
+	  cfree (destbuf);
+	  destbuf = newbuf;
+	  *((process_fd_t *) data)->fd_type = virt_fsdir;
+	}
     }
   return fs;
 }