Remove ill-advised cygwin_props

Cygwin_props have been invented to allow switching off the unique
installation keys in the first place, supposedly for debugging.
This never really was a good idea, after all we *want* the installations
to be independent and there's no good reason to break that, not even
for debugging purposes.

Other than that, cygwin_props were meant to be used for some other global
settings which never took place.  There's just no good reason to tweak
the DLL binary invisibly where a setting could be done in a file or the
environment.

This patch removes the cygwin_props entirely, including the related
settings in cygcheck.

cygwin:
	* cygprops.h: Remove file.
	* globals.cc (cygwin_props): Remove.
	* cygheap.cc (init_cygheap::init_installation_root): Drop removing
	installation key.

utils:
	* cygcheck.cc: Drop including cygprops.h.  Remove now unused option
	values.
	(unique_object_name_opt): Remove.
	(handle_unique_object_name): Remove function.
	(usage): Remove text for unique-object-names options.
	(longopts): Remove unique-object-names options.
	(main): Drop handling unique-object-names options.

doc:
	* utils.xml (cygcheck): Remove text for unique-object-names options.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

5 files changed, 1 insertions, 215 deletions

diff --git a/winsup/cygwin/cygheap.cc b/winsup/cygwin/cygheap.cc
index 4932cf0b1..7a18d18a6 100644
--- a/winsup/cygwin/cygheap.cc
+++ b/winsup/cygwin/cygheap.cc
@@ -219,12 +219,6 @@ init_cygheap::init_installation_root ()
 				    installation_root)))
 	break;
     }
-
-  if (cygwin_props.disable_key)
-    {
-      installation_key.Length = 0;
-      installation_key.Buffer[0] = L'\0';
-    }
 }
 
 void __stdcall
diff --git a/winsup/cygwin/cygprops.h b/winsup/cygwin/cygprops.h
deleted file mode 100644
index 70ea3cc5a..000000000
--- a/winsup/cygwin/cygprops.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/* cygprops.h: Cygwin DLL properties
-
-   Copyright 2009, 2012 Red Hat, Inc.
-
-This file is part of Cygwin.
-
-This software is a copyrighted work licensed under the terms of the
-Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
-details. */
-
-#pragma once
-/* DLL properties data. */
-struct cygwin_props_t
-{
-  char magic[68];
-  ULONG size;
-  ULONG disable_key;
-};
-
-#define CYGWIN_PROPS_MAGIC \
-  "Fortunately, I keep my feathers numbered for just such an emergency"
diff --git a/winsup/cygwin/globals.cc b/winsup/cygwin/globals.cc
index 80e0f0db3..990158e92 100644
--- a/winsup/cygwin/globals.cc
+++ b/winsup/cygwin/globals.cc
@@ -13,7 +13,6 @@ details. */
 #include "winsup.h"
 #include "cygtls.h"
 #include "perprocess.h"
-#include "cygprops.h"
 #include "thread.h"
 #include <malloc.h>
 #include <cygwin/version.h>
@@ -160,19 +159,6 @@ const int __collate_load_error = 0;
   extern UNICODE_STRING _RDATA ro_u_natdev = _ROU (L"Device");
   #undef _ROU
 
-  /* Cygwin properties are meant to be readonly data placed in the DLL, but
-     which can be changed by external tools to make adjustments to the
-     behaviour of a DLL based on the binary of the DLL itself.  This is
-     different from $CYGWIN since it only affects that very DLL, not all
-     DLLs which have access to the $CYGWIN environment variable.  We use the
-     same _RDATA trick as for the above UNICODE_STRINGs. */
-  extern cygwin_props_t _RDATA cygwin_props =
-  {
-    CYGWIN_PROPS_MAGIC,
-    sizeof (cygwin_props_t),
-    0
-  };
-
   /* This is an exported copy of environ which can be used by DLLs
      which use cygwin.dll.  */
   char **__cygwin_environ;
diff --git a/winsup/doc/utils.xml b/winsup/doc/utils.xml
index a904c34fd..8c5a619b8 100644
--- a/winsup/doc/utils.xml
+++ b/winsup/doc/utils.xml
@@ -35,9 +35,6 @@ cygcheck -f FILE [FILE]...
 cygcheck -l [PACKAGE]...
 cygcheck -p REGEXP
 cygcheck --delete-orphaned-installation-keys
-cygcheck --enable-unique-object-names Cygwin-DLL
-cygcheck --disable-unique-object-names Cygwin-DLL
-cygcheck --show-unique-object-names Cygwin-DLL
 cygcheck -h
 	</screen>
       </refsynopsisdiv>
@@ -63,15 +60,6 @@ At least one command option or a PROGRAM is required, as shown above.
                        Delete installation keys of old, now unused
                        installations from the registry.  Requires the right
                        to change the registry.
-  --enable-unique-object-names Cygwin-DLL
-  --disable-unique-object-names Cygwin-DLL
-  --show-unique-object-names Cygwin-DLL
-                       Enable, disable, or show the setting of the
-                       \"unique object names\" setting in the Cygwin DLL
-                       given as argument to this option.  The DLL path must
-                       be given as valid Windows(!) path.
-                       See the users guide for more information.
-                       If you don't know what this means, don't change it.
   -v, --verbose        produce more verbose output
   -h, --help           annotate output with explanatory comments when given
                        with another command, otherwise print this help
@@ -227,52 +215,6 @@ coreutils-5.3.0-6         GNU core utilities (includes fileutils, sh-utils and t
       which the installation doesn't exist anymore. To get rid of these
       orphaned registry entries, use the <command>cygcheck
       --delete-orphaned-installation-keys</command> command.</para>
-
-    <para> Each Cygwin DLL generates a key value from its installation path.
-      This value is not only stored in the registry, it's also used to generate
-      global object names used for interprocess communication. This keeps
-      different Cygwin installations separate. Processes running under a Cygwin
-      DLL installed in C:\cygwin don't see processes running under a Cygwin DLL
-      installed in C:\Program Files\cygwin. This allows running multiple
-      versions of Cygwin DLLs without these versions to interfere with each
-      other, or to run small third-party installations for a specific purpose
-      independently from a Cygwin net distribution. </para>
-
-    <para> For debugging purposes it could be desired that the various Cygwin
-      DLLs use the same key, independently from their installation paths. If
-      the DLLs have different versions, trying to run processes under these
-      DLLs concurrently will result in error messages like this one:</para>
-
-    <screen>
-*** shared version mismatch detected - 0x8A88009C/0x75BE0074.
-This problem is probably due to using incompatible versions of the Cygwin DLL.
-Search for cygwin1.dll using the Windows Start->Find/Search facility
-and delete all but the most recent version.  The most recent version *should*
-reside in x:\\cygwin\\bin, where 'x' is the drive on which you have
-installed the cygwin distribution.  Rebooting is also suggested if you
-are unable to find another Cygwin DLL.
-</screen>
-
-    <para> To disable the usage of a unique key value of a certain Cygwin DLL,
-      use the <command>cygcheck --disable-unique-object-names
-      Cygwin-DLL</command> command. <literal>Cygwin-DLL</literal> is the
-      Windows path (*not* a Cygwin POSIX path) to the DLL for which you want to
-      disable this feature. Note that you have to stop all Cygwin processes
-      running under this DLL, before you're allowed to change this setting. For
-      instance, run <command>cygcheck</command> from a DOS command line for
-      this purpose.</para>
-
-    <para>To re-enable the usage of a unique key, use the <command>cygcheck
-      --enable-unique-object-names Cygwin-DLL</command> command. This option
-      has the same characteristics as the
-      <literal>--disable-unique-object-names</literal> option</para>
-
-    <para>Finally, you can use <command>cygcheck --show-unique-object-names
-      Cygwin-DLL</command> to find out if the given Cygwin DLL use unique
-      object names or not. In contrast to the <literal>--disable-...</literal>
-      and <literal>--enable-...</literal> options, the
-      <literal>--show-unique-object-names</literal> option also works for
-      Cygwin DLLs which are currently in use.</para>
   </refsect1>
 
   </refentry>
diff --git a/winsup/utils/cygcheck.cc b/winsup/utils/cygcheck.cc
index d0ac4a5e9..d3c7d5d97 100644
--- a/winsup/utils/cygcheck.cc
+++ b/winsup/utils/cygcheck.cc
@@ -27,7 +27,6 @@
 #include "../cygwin/include/sys/cygwin.h"
 #define _NOMNTENT_MACROS
 #include "../cygwin/include/mntent.h"
-#include "../cygwin/cygprops.h"
 #undef cygwin_internal
 #include "loadlib.h"
 
@@ -50,7 +49,6 @@ int find_package = 0;
 int list_package = 0;
 int grep_packages = 0;
 int del_orphaned_reg = 0;
-int unique_object_name_opt = 0;
 
 static char emptystr[] = "";
 
@@ -132,9 +130,6 @@ static common_apps[] = {
 enum
 {
   CO_DELETE_KEYS = 0x100,
-  CO_ENABLE_UON = 0x101,
-  CO_DISABLE_UON = 0x102,
-  CO_SHOW_UON = 0x103
 };
 
 static int num_paths, max_paths;
@@ -1341,89 +1336,6 @@ memmem (char *haystack, size_t haystacklen,
   return NULL;
 }
 
-int
-handle_unique_object_name (int opt, char *path)
-{
-  HANDLE fh, fm;
-  void *haystack = NULL;
-
-  if (!path || !*path)
-    usage (stderr, 1);
-
-  DWORD access, share, protect, mapping;
-
-  if (opt == CO_SHOW_UON)
-    {
-      access = GENERIC_READ;
-      share = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
-      protect = PAGE_READONLY;
-      mapping = FILE_MAP_READ;
-    }
-  else
-    {
-      access = GENERIC_READ | GENERIC_WRITE;
-      share = 0;
-      protect = PAGE_READWRITE;
-      mapping = FILE_MAP_WRITE;
-    }
-
-  fh = CreateFile (path, access, share, NULL, OPEN_EXISTING,
-		   FILE_FLAG_BACKUP_SEMANTICS, NULL);
-  if (fh == INVALID_HANDLE_VALUE)
-    {
-      DWORD err = GetLastError ();
-      switch (err)
-	{
-	case ERROR_SHARING_VIOLATION:
-	  display_error ("%s still used by other Cygwin processes.\n"
-			 "Please stop all of them and retry.", path);
-	  break;
-	case ERROR_ACCESS_DENIED:
-	  display_error (
-	    "Your permissions are not sufficient to change the file \"%s\"",
-	    path);
-	  break;
-	case ERROR_FILE_NOT_FOUND:
-	  display_error ("%s: No such file.", path);
-	  break;
-	default:
-	  display_error (path, true, false);
-	  break;
-	}
-      return 1;
-    }
-  if (!(fm = CreateFileMapping (fh, NULL, protect, 0, 0, NULL)))
-    display_error ("CreateFileMapping");
-  else if (!(haystack = MapViewOfFile (fm, mapping, 0, 0, 0)))
-    display_error ("MapViewOfFile");
-  else
-    {
-      size_t haystacklen = GetFileSize (fh, NULL);
-      cygwin_props_t *cygwin_props = (cygwin_props_t *)
-	       memmem ((char *) haystack, haystacklen,
-		       CYGWIN_PROPS_MAGIC, sizeof (CYGWIN_PROPS_MAGIC));
-      if (!cygwin_props)
-	display_error ("Can't find Cygwin properties in %s", path);
-      else
-	{
-	  if (opt != CO_SHOW_UON)
-	    cygwin_props->disable_key = opt - CO_ENABLE_UON;
-	  printf ("Unique object names are %s\n",
-		  cygwin_props->disable_key ? "disabled" : "enabled");
-	  UnmapViewOfFile (haystack);
-	  CloseHandle (fm);
-	  CloseHandle (fh);
-	  return 0;
-	}
-    }
-  if (haystack)
-    UnmapViewOfFile (haystack);
-  if (fm)
-    CloseHandle (fm);
-  CloseHandle (fh);
-  return 1;
-}
-
 extern "C" NTSTATUS NTAPI RtlGetVersion (PRTL_OSVERSIONINFOEXW);
 
 static void
@@ -2231,9 +2143,6 @@ Usage: cygcheck [-v] [-h] PROGRAM\n\
        cygcheck -l [PACKAGE]...\n\
        cygcheck -p REGEXP\n\
        cygcheck --delete-orphaned-installation-keys\n\
-       cygcheck --enable-unique-object-names Cygwin-DLL\n\
-       cygcheck --disable-unique-object-names Cygwin-DLL\n\
-       cygcheck --show-unique-object-names Cygwin-DLL\n\
        cygcheck -h\n\n\
 List system information, check installed packages, or query package database.\n\
 \n\
@@ -2255,15 +2164,6 @@ At least one command option or a PROGRAM is required, as shown above.\n\
 		       Delete installation keys of old, now unused\n\
 		       installations from the registry.  Requires the right\n\
 		       to change the registry.\n\
-  --enable-unique-object-names Cygwin-DLL\n\
-  --disable-unique-object-names Cygwin-DLL\n\
-  --show-unique-object-names Cygwin-DLL\n\
-		       Enable, disable, or show the setting of the\n\
-		       \"unique object names\" setting in the Cygwin DLL\n\
-		       given as argument to this option.  The DLL path must\n\
-		       be given as valid Windows(!) path.\n\
-		       See the users guide for more information.\n\
-		       If you don't know what this means, don't change it.\n\
   -v, --verbose        produce more verbose output\n\
   -h, --help           annotate output with explanatory comments when given\n\
 		       with another command, otherwise print this help\n\
@@ -2287,9 +2187,6 @@ struct option longopts[] = {
   {"list-package", no_argument, NULL, 'l'},
   {"package-query", no_argument, NULL, 'p'},
   {"delete-orphaned-installation-keys", no_argument, NULL, CO_DELETE_KEYS},
-  {"enable-unique-object-names", no_argument, NULL, CO_ENABLE_UON},
-  {"disable-unique-object-names", no_argument, NULL, CO_DISABLE_UON},
-  {"show-unique-object-names", no_argument, NULL, CO_SHOW_UON},
   {"help", no_argument, NULL, 'h'},
   {"version", no_argument, 0, 'V'},
   {0, no_argument, NULL, 0}
@@ -2426,11 +2323,6 @@ main (int argc, char **argv)
       case CO_DELETE_KEYS:
 	del_orphaned_reg = 1;
 	break;
-      case CO_ENABLE_UON:
-      case CO_DISABLE_UON:
-      case CO_SHOW_UON:
-	unique_object_name_opt = i;
-	break;
       case 'V':
 	print_version ();
 	exit (0);
@@ -2454,7 +2346,7 @@ main (int argc, char **argv)
     }
 
   if ((check_setup || sysinfo || find_package || list_package || grep_packages
-       || del_orphaned_reg || unique_object_name_opt)
+       || del_orphaned_reg)
       && keycheck)
     usage (stderr, 1);
 
@@ -2462,11 +2354,6 @@ main (int argc, char **argv)
       && (check_setup || del_orphaned_reg))
     usage (stderr, 1);
 
-  if ((check_setup || sysinfo || find_package || list_package || grep_packages
-       || del_orphaned_reg)
-      && unique_object_name_opt)
-    usage (stderr, 1);
-
   if (dump_only && !check_setup && !sysinfo)
     usage (stderr, 1);
 
@@ -2475,8 +2362,6 @@ main (int argc, char **argv)
 
   if (keycheck)
     return check_keys ();
-  if (unique_object_name_opt)
-    return handle_unique_object_name (unique_object_name_opt, *argv);
   if (del_orphaned_reg)
     del_orphaned_reg_installations ();
   if (grep_packages)