a change in /etc.
* cygheap.h (struct init_cygheap): Add member `etc_changed_h'
and method `etc_changed'.
* grp.cc (enum grp_state): Eliminate.
(class grp_check): Ditto.
(group_state): Define as `class pwdgrp_check'.
(parse_grp): Remeber path and modification time of /etc/group file.
* passwd.cc (enum_pwd_state): Eliminate.
(class pwd_check): Ditto.
(passwd_state): Define as `class pwdgrp_check'.
(read_etc_passwd): Remember path and modification time of /etc/passwd
file.
* pwdgrp.h: New file.
(enum pwdgrp_state): Substitutes `pwd_state' and `grp_state'.
(class pwdgrp_check): Substitutes `pwd_check' and `grp_check'.
* Makefile.in: Use linker script to control location of cygheap.
* cygheap.cc (buckets): Make static.
(init_cheap): Remove special iswinnt handling. Allocate cygheap at a fixed
location. Display more info when allocation fails.
(cygheap_fixup_in_child): Try harder to move cygheap to correct location.
Display more info when allocation fails.
* fhandler.h (fhandler_socket): Add macros for tracking socket shutdown state.
* net.cc (cygwin_shutdown): Set appropriate shutdown value for future use.
* select.cc (select_stuff::cleanup): New method.
(cygwin_select): Call cleanup explicitly to avoid a race.
(select_stuff:~select_stuff): Call cleanup chain via cleanup method.
(fhandler_socket::select_read): Set *_ready when shutdown has been called on
the socket.
(fhandler_socket::select_write): Ditto.
(fhandler_socket::select_except): Ditto.
* winsup.h: Move NO_COPY to "COMMON" section.
* autoload.cc (wsock_started): Avoid initializing NO_COPY value.
* sigproc.cc: Remove initialization from NO_COPY variables.
(sigproc_init): Initialize sig_loop_wait here, rather than via initialization.
(subproc_init): Initialize proc_loop_wait here, rather than via initialization.
* fhandler.h: Move definitions of O_NOSYMLINK, O_DIROPEN and
OLD_O_NDELAY from winsup.h to here. Add O_NONBLOCK_MASK define.
* fhandler_socket.cc (fhandler_socket::close): Add hack to allow
a graceful shutdown even if shutdown() hasn't been called by the
application. Add debug output.
(fhandler_socket::ioctl): Set fhandler's NONBLOCK flag according
to FIONBIO setting.
(fhandler_socket::fcntl): Use new O_NONBLOCK_MASK define. Actually
set `request' before using it.
* fhandler_tty.cc: Use new O_NONBLOCK_MASK define throughout.
(fhandler_tty_slave::ioctl): Set fhandler's NONBLOCK flag according
to FIONBIO setting.
(fhandler_pty_master::ioctl): Ditto.
* net.cc (wsock_event::prepare): Compare WSACreateEvent return code
with `WSA_INVALID_EVENT' according to MSDN.
* syscalls.cc (_read): Use new O_NONBLOCK_MASK define.
* fhandler.cc (fhandler_base::fcntl): Only set specific O_NDELAY style flag
passed in from application.
* fhandler_socket.cc (fhandler_socket::fcntl): Ditto.
* fhandler.h: Set constant for future use.
* winsup.h: Define OLD_O_NDELAY only for old programs.
* include/cygwin/version.h: Define CYGWIN_VERSION_CHECK_FOR_OLD_O_NONBLOCK.
* dcrt0.cc (set_os_type): Set 'iswinnt' appropriately.
* cygheap.cc (init_cheap): Revert to using VirtualAlloc for allocating cygheap.
(cygheap_setup_for_child_cleanup): New function. Standard function to call
after calling CreateProcess to cleanup cygheap info passed to child.
(cygheap_fixup_in_child): Copy cygheap from shared memory into allocated space
under Windows 9x or if can't relocate shared space under NT.
* cygheap.h: Declare new function.
* spawn.cc (spawn_guts): Use cygheap_fixup_in_child.
* fork.cc (fork_parent): Ditto.
* winsup.h: Declare iswinnt.
* path.cc (path_conv::check): Add signal protection here since retrieving info
about remote shares can take some time.
* path.h (check_null_empty_str_errno): Convert to a function prototype.
* path.cc (check_null_empty_str): Move to miscfuncs.cc.
* miscfuncs.cc (check_null_empty_str_errno): New function.
(__check_null_invalid_struct): Ditto.
(__check_null_invalid_struct_errno): Ditto.
(check_null_empty_str): Change from VirtualQuery to IsBadWritePtr.
* thread.cc (check_valid_pointer): Ditto.
* resource.cc (getrlimit): Use check_null_invalid_struct macro for checking
validity of pointer.
(setrlimit): Ditto.
of file APIs mode (OEM/ANSI) here.
(codepage_init): From here.
* winsup.h (set_file_api_mode): Declare it.
* fork.cc (fork_child): Set file APIs mode in forkee.
* pinfo.h: Correctly set __SIGOFFSET.
* path.cc (hash_path_name): Avoid calling library functions for simple copying
of characters.
* shortcut.c: Use WIN32_LEAN_AND_MEAN.
* smallprint.c: Ditto.
* environ.cc (getwinenv): Minor clarity fix.
* localtime.c: No need to include windows.h
* string.h: New file.
(read_etc_group): Substitute MAX_DOMAIN_NAME by
INTERNET_MAX_HOST_NAME_LENGTH.
* passwd.cc (parse_pwd): Don't force pw_name to be lower case.
* sec_helper.cc: Substitute MAX_USER_NAME by UNLEN,
MAX_COMPUTERNAME_LENGTH by INTERNET_MAX_HOST_NAME_LENGTH throughout.
(lookup_name): Slight cleanup.
* security.cc (alloc_sd): Substitute MAX_USER_NAME by UNLEN.
* security.h: Define DEFAULT_UID as DOMAIN_USER_RID_ADMIN and
DEFAULT_GID as DOMAIN_ALIAS_RID_ADMINS.
* shared.cc (memory_init): Substitute MAX_USER_NAME by UNLEN.
* thread.h: Ditto.
* uinfo.cc (internal_getlogin): Substitute MAX_USER_NAME by UNLEN.
Substitute MAX_COMPUTERNAME_LENGTH and MAX_HOST_NAME by
INTERNET_MAX_HOST_NAME_LENGTH.
* winsup.h: Include lmcons.h. Eliminate MAX_USER_NAME and
MAX_HOST_NAME. Move DEFAULT_UID and DEFAULT_GID to security.h.
(init_exceptions): Just use init_exception_handler.
(open_stackdumpfile): New function.
(stack_info::first_time): Eliminate.
(stack_info::init): Set up fields to avoid "first_time" consideration.
(stack_info::walk): Remove "first_time" consideration.
(stackdump): Change arguments to accept initial frame pointer and open stack
file flag.
(stack): Eliminate.
(cygwin_stackdump): Use stackdump() rather than stack().
(try_to_debug): Remove all synchronization logic. Just keep looping in
exception handler until debugger notices us. Return 1 if successfully started
debugger.
(handle_exceptions): Just return if we know that we're debugging. Reorganize
to avoid creating a stackdump file if we are starting a debugger. Return from
exception handler if debugger started successfully.
(sig_handle): Create a stackdump only if debugger wasn't started.
* winsup.h (try_to_debug): Add an argument.
* cygheap.cc: Include security.h.
* grp.cc (internal_getgrent): New function.
(getgroups): Rearranged using `internal_getgrent' and the new
`cygsid' class.
* passwd.cc (internal_getpwent): New function.
* sec_acl.cc: Use new `cygsid' class throughout.
(acl_access): Use `internal_getgrent' instead of `getgrent'.
* sec_helper.cc: Use new `cygsid' class throughout.
(get_id_from_sid): Use `internal_getgrent' instead of `getgrent'.
Use `internal_getpwent' instead of `getpwent'.
* security.cc: Use new `cygsid' class throughout.
* security.h: Move `MAX_SID_LEN' from winsup.h to here.
Add extern declarations for `internal_getgrent' and `internal_getpwent'.
(class cygsid): New class.
* shared.cc (sec_user): Use new `cygsid' class.
* syscalls.cc (seteuid): Try to set owner to user and primary group to
current group in impersonation token before performing impersonation.
(setegid): Try to set primary group in process token to the new group
if ntsec is on.
* uinfo.cc (internal_getlogin): Use new `cygsid' class.
Try to set owner to user and primary group to current group in process
token if the process has been started from a non cygwin process.
(uinfo_init): Set primary group only if the process has been started
from a non cygwin process.
* winsup.h: Move define for `MAX_SID_LEN' to security.h.
chrisiasci@aol.com).
* cygwin.din: Add a new, internally used export - _check_for_executable.
* dcrt0.cc (dll_crt0_1): Set _check_for_executable for older binaries. Pass
user_data to premain functions.
* fhandler.cc (fhandler_disk_file::open): Only check for executable if the
linked program is intereested in the executable bit.
(fhandler_disk_file::check_execable_p): Delete.
* fhandler.h (executable_states): New enumeration of various states of
executable bit caring.
(fhandler_base::set_execable_p): New method.
* fhandler_termios.cc (fhandler_termios::line_edit): Flag when a signal has
been sent to the tty. Return -1 when this is so.
* fhandler_console.cc (fhandler_console::read): Return -1 when signal sending
character encountered.
* path.cc (path_conv::check): Record when path refers to a disk device. Move
executable extension check here.
(check_sysfile): Accomodate new EXEC path states.
(has_suffix): Remove.
(next_suffix): Remove.
(class suffix_scan): New clas.
(suffix_scan::has): New method.
(suffix_scan:next): New method.
(symlink_info::check): Use suffix_scan method to control for scanning for
suffixes.
* path.h (path_conv::exec_state): New method.
* perprocess.h: Make "C" friendly.
* include/cygwin/version.h: Define CYGWIN_VERSION_CHECK_FOR_S_IEXEC. Bump
CYGWIN_VERSION_API_MINOR.
* include/sys/cygwin.h: Change premain declarations.
* winsup.h: Move __cplusplus test to after builtin defines.
* child_info.h (child_info): Move shared_h, console_h to cygheap. Add mount_h.
* cygheap.h (init_cygheap): Add shared_h, console_h.
* cygheap.cc (init_cheap): Initialize heap at a fixed location after the shared
memory regions. Initialize cygheap->user name here.
* dcrt0.cc (dll_crt0_1): Call getpagesize () to initialize constants. Remove
cygheap_init since it is done in shared_init now.
(_dll_crt0): Initialize mount_h, remove shared_h and console_h initialization.
* fhandler_console.cc (console_shared_h): Eliminate.
(get_tty_stuff): Use cygheap->console_h rather than console_shared_h.
* heap.cc (heap_init): Use page size constant calculated earlier in
initialization.
* shared.cc: Eliminate cygwin_shared_h. Add cygwin_mount_h.
(mount_table_init): New function for initializing a user mount table.
(open_shared_file_map): Use constant for shared memory region. Initialize
cygheap and mount table here.
(open_shared): Improve debugging output.
(shared_info::initialize): Eliminate call to mount.init.
(shared_terminate): Use cygheap->shared_h. Close cygwin_mount_h.
(open_shared_file_map): Eliminate.
* shared_info.h (mount_info): Add a version field.
(shared_align_past): New macro for calculating location for shared memory
regions.
* sigproc.cc (init_child_info): Eliminate shared_h, console_h.
* spawn.cc (spawn_guts): Pass on cygwin_mount_h iff not a different user.
* syscalls.cc (system_info): New global holding system memory defaults.
(getpagesize): Use system_info.
* uinfo.cc (internal_getlogin): Only fill in user name if nonexistent.
* winsup.h: Declare system_info.
* passwd.cc (read_etc_passwd): Use cygheap->user.name () rather than retrieving
the name again.
* environ.cc (codepage_init): To here.
* exceptoins.cc (SIG_NONMASKABLE): Remove SIGCONT from consideration since it
is supposed to be maskable.
* signal.cc (sigaction): Ditto.
* sigproc.cc (wait_sig): Ditto.
* winsup.h: Eliminate global declaration of codepage_init.
* dcrt0.cc (dll_crt0_1): Translate command line to OEM if current codepage is
OEM.
* environ.cc: Add new option 'codepage' to CYGWIN environment variable.
* fhandler_clipboard.cc (fhandler_clipboard::read): Read clipboard in OEM mode
if current codepage is OEM.
* fhandler_console.cc (fhandler_console::read): Only translate console input if
current codepage is ANSI.
* fhandler_console.cc (fhandler_console::write_normal): Translate output data
if current codepage is ANSI.
* pinfo.cc (codepage_init): New function. Setup current codepage from CYGWIN
environment variable and set codepage for file APIs.
* security.cc (read_sd): Translate file name to it if current codepage is OEM.
* winsup.h: (sys_wcstombs,sys_mbstowcs): Use current codepage for translations
between multibyte and widechar string and vice versa.
Always check for MAX_PATH overrun. Avoid adding one too many backslashes when
src path begins with a slash. From Corinna Vinschen.
* winsup.h: Force demangling for dll_crt0 for newer compilers.
active.
* syscalls.cc (_read): Don't clear errno.
* sigproc.cc (wait_sig): Don't scan the waiting process list after a SIGCHLD if
there are no zombies to reap.
* winsup.h: Use __builtin_strcmp.
* environ.cc (posify): Don't initialize len unless it is required
(from DJ Delorie <dj@redhat.com>).
* dcrt0.cc (dll_crt0_1): Call signal_fixup_after_exec where appropriate. Set
myself->uid from parent version. Just use ThreadItem Init method. Close or
store hexec_proc as appropriate.
(_dll_crt0): Store user_data->forkee here so that proper tests can be made
subsequently.
(do_exit): Remove hExeced stuff.
* environ.cc (environ_init): Accept environ count as well as environ pointer.
* environ.h: Reflect above change.
* pinfo.cc (pinfo_init): Ditto. Accept environ count.
(fixup_in_spawned_child): Remove.
* spawn.cc (spawn_guts): Move signal code to dll_crt0_1. Don't suspend execing
process since it is no longer necessary. Store envc.
* exceptions.cc (signal_fixup_after_exec): New function.
(call_handler): Remove hExeced test.
* child_info.h (cygheap_exec_info): Store envc as well as envp.
(child_info_spawn): Store hexec_proc so that it can be closed in child.
* path.cc (normalize_posix_path): Avoid intermediate use of temporary cwd buf.
(normalize_win32_path): Ditto.
(cwdstuff::get_initial): Always set lock.
* sigproc.h: Remove hExeced.
* strace.cc (strace::vsprntf): Modify to accomodate for lack of hExeced.
* thread.cc (MTinterface::Init): Merge Init1 and ClearReent into this method.
(MTinterface::Init1): Eliminate.
(MTinterface::ClearReent): Eliminate.
* thread.h: Reflect above changes.
* include/sys/strace.h (strace): Make microseconds() public. Make various
functions 'regparm', throughout.
* pinfo.h (_pinfo): Inline simple signal manipulation functions. Requires
inclusion of thread.h which was removed from .cc files, where appropriate.
throughout.
* pinfo.cc: Eliminate signal manipulation functions.
(_pinfo::exit): Calculate total rusage for exiting process here.
* cygheap.cc (size2bucket): Eliminate.
(init_buckets): Ditto.
(_cmalloc): Calculate size and bits in a loop rather than going through a
function call.
(_crealloc): Use stored array index to calculate allocated size.
* spawn.cc (spawn_guts): Use _pinfo exit method to exit, calculating cpu usage.
specific call when appropriate.
(__set_winsock_errno): Rename from set_winsock_errno. Accept function and line
as arguments.
* path.cc (path_conv::check): Continue the neverending battle to make cygwin
properly understand that path specs ending in a slash require that the path
refer to a directory. Windows does not do this by default.
(symlink_info::check): Remove ENOTDIR test. Move it to path_conv::check.
* path.h: Remove obsolete constant.
* winsup.h (set_winsock_errno): New macro.
throughout.
* shared.h: Remove.
* cygwin_version.h: New file.
* delqueue.h: New file.
* environ.h: New file.
* host_dependent.h: New file.
* perprocess.h: New file.
* registry.h: New file.
* security.h: New file.
* child_info.h: Add specific exec class.
* cygheap.h: New file. Contains declarations for cygwin heap.
* cygheap.cc: New file. Implements cygwin heap functions.
* dcrt0.cc (quoted): Simplify due to new method for passing arguments between
cygwin programs.
(alloc_stack_hard_way): Attempt to handle overlapped stack.
(dll_crt0_1): Move child_info processing here. Accomodate new method for
passing arguments between cygwin programs. Initialize cygwin heap. Establish
__argc and __argv variables.
(_dll_crt0): Move most of child_info processing to dll_crt0_1.
(cygwin_dll_init): Remove duplication.
* dtable.cc (dtable::extend): Allocate dtable using cygwin heap.
(dtable::build_fhandler): Ditto for fhandler type being constructed.
(dtable::dup_worker): Free new fhandler from cygwin heap on error.
(dtable::select_*): Don't assume that this == fdtab.
(dtable::linearize_fd_array): Delete.
(dtable::delinearize_fd_array): Delete.
(dtable::fixup_after_exec): New file.
(dtable::vfork_child_dup): Use cygwin heap.
(dtable::vfork_parent_restore): Ditto.
* dtable.h: Remove obsolete methods. Add new method.
* environ.cc (posify): Eliminate already_posix parameter and logic.
(envsize): New function.
(_addenv): Use envsize.
(environ_init): Accept an argument pointing to an existing environment list.
If supplied, allocate space for this in the the program's heap.
* fhandler.cc (fhandler_base::operator =): Move here from fhandler.h. Use
cygwin heap to allocate filenames.
(fhandler_base::set_name): Allocate/free names from cygwin heap.
(fhandler_base::linearize): Delete.
(fhandler_base::de_linearize): Delete.
(fhandler_base::operator delete): Free from cygwin heap.
(fhandler_base::~fhandler_base): Ditto.
* fhandler.h: Accomodate elimination of *linearize and other changes above.
* fhandler_console.cc (fhandler_console::fixup_after_exec): Rename from
de_linearize.
* heap.h: New file.
* fhandler_tty.cc (fhandler_tty_slave::fhandler_tty_slave): Use cygwin heap for
name. fhandler_tty::fixup_after_exec): Rename from de_linearize.
* fork.cc (fork): Call cygheap_fixup_in_child.
* heap.cc: Use declarations in heap.h.
* malloc.cc: Sprinkle assertions throughout to catch attempts to free/realloc
something from the cygwin heap.
* path.cc: Throughout, eliminate use of per-thread cache for cwd. Use cwd_*
functions rather than cwd_* variables to access cwd_win32 and cwd_posix.
(cwd_win32): New function.
(cwd_posix): New function.
(cwd_hash): New function.
(cwd_fixup_after_exec): New function.
* path.h: Accomodate path.cc changes.
* pinfo.cc (pinfo_init): Accept a pointer to an environment table. Pass this
to environ_init. Eliminate old 'title' tests.
* pinfo.h: Accomodate above change in argument.
* spawn.cc (struct av): New method for building argv list.
(av::unshift): New method.
(spawn_guts): Allocate everything that the child process needs in the cygwin
heap and pass a pointer to this to the child. Build argv list using new
method. Eliminate delinearize stuff.
* thread.h: Eliminate _cwd_win32 and _cwd_posix buffers.
* winsup.h: Eliminate obsolete functions. Add envsize() declaration.
the process. Use new second argument to set_myself.
(cygwin_dll_init): Initialize exception list and constructor stuff here.
(_dll_crt0): And here. Also, deal with inherited pinfo shared memory region
from parent.
* pinfo.cc (set_myself): Accept a second argument signifying the a shared
memory region, passed from an execing parent.
(pinfo_init): Ditto.
* pinfo.h: Ditto.
* shared.h (child_info): Add a handle field to pass to child.
* spawn.cc (spawn_guts): Create a shared handle to pass to an execed child.
* winsup.h: Remove extraneous declaration.
required.
* errno.cc: Use DWORD to hold Windows errors.
(geterrno_from_win_error): New function.
(seterrno_from_win_error): Use geterrno_from_win_error to convert supplied
windows error (suggested by Corinna Vinschen).
* path.cc (symlink_info): Add error element.
* path.cc (path_conv::check): Remove errno setting. Use new symlink_info errno
element to set path_conv error, where appropriate.
(symlink_info::check): Set error element rather than attempting to manipulate
errno. Add more checks for trailing / and /.. even though they are currently
useless. Avoid setting EINVAL.
* path.cc (normalize_posix_path): Correct check for trailing /.
recovery.
* spawn.cc (spawn_guts): Reorganize slightly to consolidate handling when there
is a CreateProcess error.
(_spawnve): Only longjmp back to vfork handling when a process has been
successfuly started.
* winsup.h (vfork_save): Extend to include frame info. Remove obsolete cpplus
conditionals.
* *.cc: put winsup.h before other headers (for __INSIDE_CYGWIN__);
use cur_environ() instead of just environ
* times.cc: remove import protections
* glob.c: add winsup.h
* localtime.c: ditto
* smallprint.c: ditto
* Makefile.in: don't __INSIDE_CYGWIN__ as it messes up profiling.
variable argument macros when possible.
* sigproc.cc: Throughout, use sigproc_printf rather than sip_printf.
* strace.cc (strace::prntf): Remove 'active' check, since callers are supposed
to ensure this.
(__system_printf): Remove. Subsumed by strace::prntf.
* winsup.h: Define "NEW_MACRO_VARARGS" to indicate when to use new macro
varargs capability.
the changes below. Redefine process structure to avoid a fixed size table.
Redefine pinfo/_pinfo classes. Use these throughout.
* dcrt0.cc (dll_crt0_1): Accomodate set_myself argument change.
(__api_fatal): Accomodate _pinfo::record_death argument change.
* exceptions.cc (really_exit): Ditto.
(sig_handle_tty_stop): Use pinfo constructor to access process info.
(events_init): Don't create pinfo_mutex since it is no longer required.
* external.cc (fillout_pinfo): Use winpids class to iterate over all system
pids.
(cygwin_internal): lock_pinfo_for_update and unlock_pinfo are now noops.
* fhandler_termios.cc (fhandler_termios::set_ctty): Use pinfo constructor to
access process info.
* fork.cc (fork): Reorganize to initialize child info after the child has
started since that is when we know the child's winpid, which is necessary to
allocate the pinfo shared memory.
* mmap.cc (recreate_mmaps_after_fork): Change arg type to _pinfo.
* pinfo.cc: Rename pinfo methods to _pinfo throughout. Eliminate pinfo_list
stuff.
(set_myself): Accept a pid argument now. Call pinfo initializer to initialize
myself. Detect when this is an "execed" process and create an "indirect" pid
block.
(pinfo_init): Accomodate set_myself arg change.
(procinfo): Remove.
(pinfo::lock_pinfo): Remove.
(pinfo::unlock_pinfo): Remove.
(pinfo::init): New method. Allocates shared memory space for process pinfo
structure.
(pinfo::record_death): Don't call locking functions.
(cygwin_winpid_to_pid): Simplify by using new pinfo constructor.
(EnumProcessesW95): New function for iterating over processes on Windows 95.
(winpids::winpids): New constructor for winpids class. Sets up a list of
process ids.
(enum_init): Initialize w95/wnt pid enumerators.
* shared.cc (shared-info::initialize): Remove pid initialization.
* shared.h: Move pinfo stuff into pinfo.h.
(class shared_info): Remove pinfo_list element.
* signal.cc (kill_worker): Use pinfo constructor to access process info.
(kill_pgrp): Ditto. Use winpids methods to access list of processes.
* sigproc.cc: Throughout, modify to use _pinfo where appropriate.
(proc_exists (pid_t)): New function. Determines if a process exists based on
the pid.
(proc_exists (_pinfo *p): Use new proc_exists function above.
(proc_subproc): Copy pinfo stuff around rather than _pinfo pointers. Try to be
careful about releasing shared memory when we don't need it anymore. Remove
pinfo locks.
(remove_zombies): Remove pinfo memory when zombie is going away.
* sigproc.h: Reflect _pinfo/pinfo changes in sigproc.cc.
* spawn.cc (spawn_guts): Eliminate pinfo *child argument. Reorganize to only
initialize child pinfo after process has been started and we know the windows
pid.
(_spawnve): Reflect spawn_guts changes.
* syscalls.cc (setpgid): Use pinfo constructor to access process info.
(getpgid): Ditto.
(internal_getlogin): Use _pinfo.
* winsup.h: Eliminate pinfo_mutex. Eliminate spawn_guts declaration since it
is static now. Reflect set_myself argument change.
* include/sys/cygwin.h: Add some PID_* enums to accomodate new pinfo stuff.
* include/cygwin/version.h: Update minor version for cygdrive changes below.
* winsup.h: Add new macros sys_wcstombs and sys_mbstowcs.
* syscalls.cc (_link): Replace calls to mbstowcs by call to
sys_mbstowcs.
* uinfo.cc (internal_getlogin): Replace calls to wcstombs and
mbstowcs by calls to sys_wcstombs and sys_mbstowcs. Replace
usage of constants by meaningful defines. Use result of
GetSystemDirectory for HOMEPATH and HOMEDRIVE as a last resort.
(environ_init): Explicitly initialize __cygwin_environ.
(cur_environ): New function. Detects when user has updated their environment.
* exec.cc: Use 'environ' define throughout rather than __cygwin_environ.
* spawn.cc: Ditto.
* winsup.h: Declare cur_environ, main_environ, environ.