`cygwin_set_impersonation_token'.
* dcrt0.cc (dll_crt0_1): Eliminate superfluous conditional
statements.
Add load statements for `ImpersonateLoggedOnUser', `LogonUserA'
and `RevertToSelf'.
* fork.cc (fork): Care for correct impersonation of parent
and child process.
* security.cc (cygwin_set_impersonation_token): New function.
(cygwin_logon_user): Ditto.
shared.h (class pinfo): New members `orig_uid', `orig_gid',
`real_uid' nad `real_gid'.
spawn.cc (spawn_guts): Care for impersonation when starting
child process in a different user context.
* syscalls.cc (setgid): Call `setegid' now. Set real_gid.
(setuid): Call `seteuid' now. Set real_uid.
(seteuid): Functionality moved from setuid to here. Care for
correct impersonation.
(setegid): Functionality moved from setgid to here.
* uinfo.cc (uinfo_init): Initialization of additional pinfo
members.
(getuid): Return real uid.
(getgid): Return real gid.
(geteuid): Return effective uid.
(getegid): Return effective gid.
include/sys/cygwin.h: Add prototypes for `cygwin_logon_user' and
`cygwin_set_impersonation_token'.
include/cygwin/version.h: Bumb API minor version to 22.
* external.cc: Eliminate obsolete include.
* getopt.c (getopt_long): Fix compiler warning.
* shared.h: Moved PID_ definitions to include/sys/cygwin so that they can be
used by external programs.
* include/sys/cygwin.h: Move external definitions here. Include sys/resource.h
to avoid having to do this everywhere.
name check. Windows 95 seems to null-terminate the directory otherwise.
(interrupt_on_return): Issue a fatal error if we can't find the caller's stack.
* spawn.cc (find_exec): Accept a path_conv argument rather than a buffer so
that the caller can find things out about a translated path.
(perhaps_suffix): Ditto.
(spawn_guts): Allocate path_conv stuff here so that we can find out stuff about
the translated path (this is work in progress).
* environ.cc (environ_init): Accept an as-yet unused argument indicating
whether we were invoked from a cygwin parent or not.
(winenv): Ditto.
(posify): Accept an argument indicating whether the path has already been
translated.
* dlfcn.cc (check_access): Provide a path_conv buffer to find_exec.
* exec.cc (sexecvpe): Ditto.
* path.cc (path_conv::check): Rename from path_conv::path_conv.
(mount_item::getmntent): Recognize "Cygwin executable" bit.
(symlink_info::check): Remove debugging statements.
* path.h (class path_conv): Add iscygexec method. Rewrite constructor to call
"check" method to allow multiple operations on a path_conv variable.
* pinfo.cc (pinfo_init): Pass argument to environ_init.
* shared.h: Bump PROC_MAGIC.
* winsup.h: Reflect above changes to function arguments.
* include/sys/mount.h: Add MOUNT_CYGWIN_EXEC type.
* path.h: Make PATH_SYMLINK an alias for MOUNT_SYMLINK.
* syscalls.cc (stat_worker): Use extension search mechanism in path_conv to
look for .exe rather than trying to special case it here.
* mount.h: Make MOUNT_SYMLINK a real option.