The original dll_init code was living under the wrong assumption that
dll_dllcrt0_1 and in turn dll_list::alloc will be called for each
LoadLibrary call. The same wrong assumption was made for
cygwin_detach_dll/dll_list::detach called via FreeLibrary.
In reality, dll_dllcrt0_1 gets only called once at first LoadLibrary
and cygwin_detach_dll once at last FreeLibrary.
In effect, reference counting for DLLs was completely broken after fork:
parent:
l1 = dlopen ("lib1"); // LoadLibrary, LoadCount = 1
l2 = dlopen ("lib1"); // LoadLibrary, LoadCount = 2
fork (); // LoadLibrary in the child, LoadCount = 1!
child:
dlclose (l1); // FreeLibrary actually frees the lib
x = dlsym (l2); // SEGV
* Move reference counting to dlopen/dlclose since only those functions
have to keep track of loading/unloading DLLs in the application context.
* Remove broken accounting code from dll_list::alloc and dll_list::detach.
* Fix error handling in dlclose.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Note that this always returns with dli_sname and dli_saddr set to NULL,
indicating no symbol matching addr could be found.
Signed-off-by: Jon Turney <jon.turney@dronecode.org.uk>
This patch alters the behaviour of dll_list::topsort to preserve the
order of dlopen'd units.
The load order of unrelated DLLs is reversed every time fork is called,
since dll_list::topsort finds the tail of the list and then unwinds to
reinsert items. My change takes advantage of what should be undefined
behaviour in dll_list::populate_deps (ndeps non-zero and ndeps and deps
not initialised) to allow the deps field to be initialised prior to the
call and appended to, rather than overwritten.
All DLLs which have been dlopen'd have their deps list initialised with
the list of all previously dlopen'd units. These extra dependencies mean
that the unwind preserves the order of dlopen'd units.
The motivation for this is the FlexDLL linker used in OCaml. The FlexDLL
linker allows a dlopen'd unit to refer to symbols in previously dlopen'd
units and it resolves these symbols in DllMain before anything else has
initialised (including the Cygwin DLL). This means that dependencies may
exist between dlopen'd units (which the OCaml runtime system
understands) but which Windows is unaware of. During fork, the
process-level table which FlexDLL uses to get the symbol table of each
DLL is copied over but because the load order of dlopen'd DLLs is
reversed, it is possible for FlexDLL to attempt to access memory in the
DLL before it has been loaded and hence it fails with an access
violation. Because the list is reversed on each call to fork, it means
that a subsequent call to fork puts the DLLs back into the correct
order, hence "even" invocations of fork work!
An interesting side-effect is that this only occurs if the DLLs load at
their preferred base address - if they have to be rebased, then FlexDLL
works because at the time that the dependent unit is loaded out of
order, there is still in memory the "dummy" DONT_RESOLVE_DLL_REFERENCES
version of the dependency which, as it happens, will contain the correct
symbol table in the data section. For my tests, this initially appeared
to be an x86-only problem, but that was only because the two DLLs on x64
should have been rebased.
Signed-off-by: David Allsopp <david.allsopp@metastack.com>
Update the getconf utility to support the new flag as well as
_PC_POSIX_PERMISSIONS and _PC_POSIX_SECURITY. These were previously
unsupported, probably as an oversight.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Long-standing problem in one of the corner cases of rename(2):
If we rename a directory a check is performed to see if newpath is
identical to oldpath or a subdir of oldpath. This check is
(accidentally? no hints anywhere in ChangeLogs or code) performed
case-insensitive for as long as we use Unicode paths and NT functions.
This leads to the problems described in
https://cygwin.com/ml/cygwin/2016-09/msg00264.html
Change this to be conditional case-sensitive as all other checks but
let's take this with a grain of salt. There may be corner-cases in
this corner-case which require to chek parts of the path always
case-insensitive. Off the top of my head I can't construct such a
case but that's no proof they don't exist :}
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
On Windows 8.1 and later, the NetUserChangePassword call apparently
doesn't accept the usual "\\server" string anymore, but requires to
use the "domain" instead, otherwise it emits en error code 1265,
ERROR_DOWNGRADE_DETECTED. Since this is accepted by pre-8.1 as well,
use the domain indiscriminately when calling NetUserChangePassword
from passwd(1).
While at it, do some minor cleanup in passwd.c.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This patch adds pthread_getname_np and pthread_setname_np.
These were added to glibc in 2.12[1] and are also present in some form on
NetBSD and several UNIXes.
The code is based on NetBSD's implementation with changes to better match
Linux behaviour.
Implementation quirks:
* pthread_setname_np with a NULL pointer segfaults (as linux)
* pthread_setname_np returns ERANGE for names longer than 16 characters (as
linux)
* pthread_getname_np with a NULL pointer returns EFAULT (as linux)
* pthread_getname_np with a buffer length of less than 16 returns ERANGE (as
linux)
* pthread_getname_np truncates the thread name to fit the buffer length.
This guarantees success even when the default thread name is longer than 16
characters, but means there is no way to discover the actual length of the
thread name. (Linux always truncates the thread name to 16 characters)
* Changing program_invocation_short_name changes the default thread name (on
linux, it has no effect on the default thread name)
I'll leave it up to you to decide if any of these matter.
This is implemented via class pthread_attr to make it easier to add
pthread_attr_[gs]etname_np (present in NetBSD and some UNIXes) should it
ever be added to Linux (or we decide we want it anyway).
[1] https://sourceware.org/git/?p=glibc.git;a=blob;f=NEWS
POSIX requires that SSIZE_MAX have the same type as ssize_t, but
on 32-bit, we were defining it as a long even though ssize_t
resolves to an int. It also requires that SSIZE_MAX be usable
via preprocessor #if, so we can't cheat and use a cast.
If this were newlib, I'd have had to hack _intsup.h to probe the
qualities of size_t (via gcc's __SIZE_TYPE__), similar to how we
already probe the qualities of int8_t and friends, then cross our
fingers that ssize_t happens to have the same rank (most systems
do, but POSIX permits a system where they differ such as size_t
being long while ssize_t is int). Unfortunately gcc gives us
neither __SSIZE_TYPE__ nor __SSIZE_MAX__. On the other hand, our
limits.h is specific to cygwin, so we can just shortcut to the
correct results rather than being generic to all possible ABI.
Signed-off-by: Eric Blake <eblake@redhat.com>
* fhandler.h (class fhandler_base): Convert unique_id to int64_t.
(fhandler_base::set_ino): New protected inline method.
(fhandler_base::get_unique_id): Convert to int64_t.
(fhandler_base::set_unique_id): New inline method taking int64_t.
(fhandler_pipe::fstat): Declare.
(fhandler_pipe::init): Take extra parameter.
(fhandler_pipe::create): Ditto.
* fhandler_socket.cc (fhandler_socket::init_events): Set inode number
to serial number.
(fhandler_socket::fstat): Set device to DEV_TCP_MAJOR. Create st_ino
from get_ino.
* include/cygwin/signal.h (struct _sigcommune): Replace
_si_pipe_fhandler with _si_pipe_unique_id.
* pinfo.h (_pinfo::pipe_fhandler): Take unique id instead of HANDLE.
* pinfo.cc (commune_process): Accommodate change to _si_pipe_unique_id.
(_pinfo::commune_request): Ditto.
(_pinfo::pipe_fhandler): Ditto.
* pipe.cc (fhandler_pipe::init): Take unique id as argument and set
inode number and unique_id from there.
(fhandler_pipe::open): Rework to find any matching pipe from unique
id in filename.
(fhandler_pipe::get_proc_fd_name): Create filename using inode number.
(fhandler_pipe::create): Generate and return unique id from process pid
and pipe_unique_id. In outer method, call init with additional unique
id as parameter.
(fhandler_pipe::fstat): New method.
(pipe_worker): Accommodate using 64 bit inode number in filename.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* cygpath.cc (do_sysfolders): Drop lame workaround to fix case of
directory returned by GetSystemDirectoryW. Try to fix case of
any path returned by this function in case it has to return a
POSIX path to support case-sensitivity.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* setfacl.cc (modacl): Move recomputing mask into new function.
(check_got_mask): New function checking if mask is in input.
(recompute_mask): New function to recompute mask.
(addmissing): Align mask computation to Linux setfacl.
(setfacl): Call check_got_mask and recompute_mask on Set, Delete and
Modify actions.
(usage): Rename --substitute to --set.
(longopts): Add --set option.
* utils.xml (setfacl): Rename --substitute to --set.
* new-features.xml (ov-new2.4): Rephrase setfacl changes.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* include/sys/cygwin.h (CCP_PROC_CYGDRIVE): New flag.
* mount.cc (mount_info::cygdrive_posix_path): Take flag values rather
than just a trailing_slash_p bool. Emit /proc/cygdrive path if
CCP_PROC_CYGDRIVE flag is given.
(mount_info::conv_to_posix_path): Take flag values rather than just
a keep_rel_p bool. Rename _p variables. Print flag value as hex in
debug_printf. Call cygdrive_posix_path with flag values.
* mount.h (mount_info::cygdrive_posix_path): Accommodate above change
in declaration.
(mount_info::conv_to_posix_path): Ditto.
* fhandler_process.cc (format_process_exename): Accommodate change to
mount_info::conv_to_posix_path.
* path.cc (cygwin_conv_path): Ditto.
* cygpath.cc (absolute_flag): Initialize to CCP_RELATIVE to simplify
expressions.
(cygdrive_flag): New global flag.
(long_options): Add --proc-cygdrive option.
(options): Add -U option.
(usage): Add description for -U option.
(do_sysfolders): Or cygdrive_flag to cygwin_conv_path call.
(do_pathconv): Simply or absolute_flag to conv_func. Or
cygdrive_flag to conv_func.
(do_options): Initalize absolute_flag to CCP_RELATIVE. Initialize new
cygdrive_flag. Set absolute_flag to CCP_ABSOLUTE on -a. Set
cygdrive_flag to CCP_PROC_CYGDRIVE on -U.
* new-features.xml (ov-new2.4): Document cygpath -U option.
* utils.xml (cygpath): Ditto.
* path.xml (func-cygwin-path): Add CCP_PROC_CYGDRIVE description.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* cygtls.h (_cygtls::wait_signal_arrived): Renamed from
set_signal_arrived.
(_cygtls::set_signal_arrived): New function signalling signal_arrived.
(_cygtls::reset_signal_arrived): Don't reset will_wait_for_signal.
(_cygtls::unwait_signal_arrived): New function only resetting
will_wait_for_signal.
(class wait_signal_arrived): Rename from set_signal_arrived.
Accommodate name change throughout Cygwin.
(wait_signal_arrived::~wait_signal_arrived): Call
_cygtls::unwait_signal_arrived. Add comment.
* cygserver_ipc.h (ipc_set_proc_info): Fetch signal_arrived handle
via call to _cygtls::get_signal_arrived.
* exceptions.cc (_cygtls::interrupt_setup): Signal signal_arrived via
call to _cygtls::set_signal_arrived.
(_cygtls::handle_SIGCONT): Ditto.
* fhandler_socket.cc (fhandler_socket::wait_for_events): Generate
WSAEVENT array prior to entering wait loop. Add cancel event object
if available. Remove calls to pthread_testcancel and just call
pthread::static_cancel_self if the cancel event object is signalled.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* nlsfuncs.cc (setlocaleinfo): New macro calling __setlocaleinfo.
(__setlocaleinfo): New function to set a locale-specific character
to an explicit wchar_t value.
(__set_lc_numeric_from_win): Handle fa_IR and ps_AF locales to return
same decimal point and thousands separator characters as on Linux.
(__set_lc_monetary_from_win): Ditto for monetary characters.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Corinna Vinschen
Yaakov Selkowitz
Jon Turney
David Allsopp
Ken Brown
Eric Blake
Thomas Wolff