Index: external.cc
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/external.cc,v
retrieving revision 1.50
diff -u -p -r1.50 external.cc
--- external.cc	28 Mar 2003 14:21:40 -0000	1.50
+++ external.cc	2 Apr 2003 11:43:29 -0000
@@ -28,6 +28,17 @@ details. */
 #include "wincap.h"
 #include "heap.h"
 #include "cygthread.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/utsname.h>
+#include <sys/vfs.h>
+
+#define is_winnt	(GetVersion() < 0x80000000)
+#define ntsec_on(c)	((c) && strstr((c),"ntsec") && !strstr((c),"nontsec"))
+#define ntsec_off(c)	((c) && strstr((c),"nontsec"))
+#define ntea_on(c)	((c) && strstr((c),"ntea") && !strstr((c),"nontea"))
+#define HAS_CREATE_TOKEN 1
+#define HAS_NTSEC_BY_DEFAULT 2
 
 static external_pinfo *
 fillout_pinfo (pid_t pid, int winpid)
@@ -121,6 +132,99 @@ get_cygdrive_prefixes (char *user, char 
   return res;
 }
 
+static int
+has_capability (int what)
+{
+  /* has_capability() basically calls uname() and checks if
+     specific capabilities of Cygwin can be evaluated from that.
+     This simplifies the calling functions which only have to ask
+     for a capability using has_capability() instead of having
+     to figure that out by themselves. */
+  static int inited;
+  static int has_create_token;
+  static int has_ntsec_by_default;
+
+  if (!inited)
+    {
+      struct utsname uts;
+
+      if (!uname (&uts))
+	{
+	  int major_high = 0;
+	  int major_low = 0;
+	  int minor = 0;
+	  int api_major_version = 0;
+	  int api_minor_version = 0;
+	  char *c;
+
+	  sscanf (uts.release, "%d.%d.%d", &major_high, &major_low, &minor);
+	  c = strchr (uts.release, '(');
+	  if (c)
+	    sscanf (c + 1, "%d.%d", &api_major_version, &api_minor_version);
+	  if (major_high > 1 ||
+	      (major_high == 1 && (major_low > 3 ||
+				   (major_low == 3 && minor >= 2))))
+	    has_create_token = 1;
+	  if (api_major_version > 0 || api_minor_version >= 56)
+	    has_ntsec_by_default = 1;
+	  inited = 1;
+	}
+    }
+  switch (what)
+    {
+    case HAS_CREATE_TOKEN:
+      return has_create_token;
+    case HAS_NTSEC_BY_DEFAULT:
+      return has_ntsec_by_default;
+    }
+  return 0;
+}
+
+static int
+check_ntsec (const char *filename)
+{
+  char *cygwin;
+  int allow_ntea = 0;
+  int allow_ntsec = 0;
+  struct statfs fsstat;
+
+  /* Windows 95/98/ME don't support file system security at all. */
+  if (!is_winnt)
+    return 0;
+
+  /* Evaluate current CYGWIN settings. */
+  cygwin = getenv ("CYGWIN");
+  allow_ntea = ntea_on (cygwin);
+  allow_ntsec = ntsec_on (cygwin) ||
+    (has_capability (HAS_NTSEC_BY_DEFAULT) && !ntsec_off (cygwin));
+
+  /*
+   * `ntea' is an emulation of POSIX attributes. It doesn't support
+   * real file level security as ntsec on NTFS file systems does
+   * but it supports FAT filesystems. `ntea' is minimum requirement
+   * for security checks.
+   */
+  if (allow_ntea)
+    return 1;
+
+  /*
+   * Retrieve file system flags. In Cygwin, file system flags are
+   * copied to f_type which has no meaning in Win32 itself.
+   */
+  if (statfs (filename, &fsstat))
+    return 1;
+
+  /*
+   * Only file systems supporting ACLs are able to set permissions.
+   * `ntsec' is the setting in Cygwin which switches using of NTFS
+   * ACLs to support POSIX permissions on files.
+   */
+  if (fsstat.f_type & FS_PERSISTENT_ACLS)
+    return allow_ntsec;
+
+  return 0;
+}
+
 extern "C" unsigned long
 cygwin_internal (cygwin_getinfo_types t, ...)
 {
@@ -246,6 +350,11 @@ cygwin_internal (cygwin_getinfo_types t,
 	  pid_t pid = va_arg (arg, pid_t);
 	  pinfo p (pid);
 	  return (DWORD) p->cmdline (n);
+	}
+      case CW_CHECK_NTSEC:
+	{
+	  char *filename = va_arg (arg, char *);
+	  return check_ntsec (filename);
 	}
       default:
 	return (DWORD) -1;
Index: include/cygwin/version.h
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/include/cygwin/version.h,v
retrieving revision 1.112
diff -u -p -r1.112 version.h
--- include/cygwin/version.h	19 Mar 2003 20:13:57 -0000	1.112
+++ include/cygwin/version.h	2 Apr 2003 11:43:29 -0000
@@ -197,12 +197,13 @@ details. */
 		  fgetpos64 fopen64 freopen64 fseeko64 fsetpos64 ftello64
 		  _open64 _lseek64 _fstat64 _stat64 mknod32
        80: Export pthread_rwlock stuff
+       81: CW_CHECK_NTSEC addition to external.cc
      */
 
      /* Note that we forgot to bump the api for ualarm, strtoll, strtoull */
 
 #define CYGWIN_VERSION_API_MAJOR 0
-#define CYGWIN_VERSION_API_MINOR 80
+#define CYGWIN_VERSION_API_MINOR 81
 
      /* There is also a compatibity version number associated with the
 	shared memory regions.  It is incremented when incompatible
Index: include/sys/cygwin.h
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/include/sys/cygwin.h,v
retrieving revision 1.42
diff -u -p -r1.42 cygwin.h
--- include/sys/cygwin.h	28 Mar 2003 14:21:40 -0000	1.42
+++ include/sys/cygwin.h	2 Apr 2003 11:43:29 -0000
@@ -71,7 +71,8 @@ typedef enum
     CW_STRACE_ACTIVE,
     CW_CYGWIN_PID_TO_WINPID,
     CW_EXTRACT_DOMAIN_AND_USER,
-    CW_CMDLINE
+    CW_CMDLINE,
+    CW_CHECK_NTSEC
   } cygwin_getinfo_types;
 
 #define CW_NEXTPID	0x80000000	/* or with pid to get next one */