Provide ucontext to signal handlers

Add ucontext.h header, defining ucontext_t and mcontext_t types.

Provide sigaction sighandlers with a ucontext_t parameter, containing stack and
context information.

	* include/sys/ucontext.h : New header.
	* include/ucontext.h : Ditto.
	* exceptions.cc (call_signal_handler): Provide ucontext_t
	parameter to signal handler function.

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
This commit is contained in:
Jon TURNEY
2015-03-30 20:31:13 +01:00
committed by Corinna Vinschen
parent 38a8d3e216
commit 9e8932d6da
4 changed files with 70 additions and 2 deletions

View File

@ -16,6 +16,7 @@ details. */
#include <stdlib.h>
#include <syslog.h>
#include <wchar.h>
#include <ucontext.h>
#include "cygtls.h"
#include "pinfo.h"
@ -1489,15 +1490,33 @@ _cygtls::call_signal_handler ()
siginfo_t thissi = infodata;
void (*thisfunc) (int, siginfo_t *, void *) = func;
ucontext_t thiscontext;
thiscontext.uc_link = 0;
thiscontext.uc_flags = 0;
if (thissi.si_cyg)
memcpy (&thiscontext.uc_mcontext, ((cygwin_exception *)thissi.si_cyg)->context(), sizeof(CONTEXT));
else
RtlCaptureContext ((CONTEXT *)&thiscontext.uc_mcontext);
/* FIXME: Really this should be the context which the signal interrupted? */
/* FIXME: If/when sigaltstack is implemented, this will need to do
something more complicated */
thiscontext.uc_stack.ss_sp = NtCurrentTeb ()->Tib.StackBase;
thiscontext.uc_stack.ss_flags = 0;
if (!NtCurrentTeb ()->DeallocationStack)
thiscontext.uc_stack.ss_size = (uintptr_t)NtCurrentTeb ()->Tib.StackLimit - (uintptr_t)NtCurrentTeb ()->Tib.StackBase;
else
thiscontext.uc_stack.ss_size = (uintptr_t)NtCurrentTeb ()->DeallocationStack - (uintptr_t)NtCurrentTeb ()->Tib.StackBase;
sigset_t this_oldmask = set_process_mask_delta ();
thiscontext.uc_sigmask = this_oldmask;
int this_errno = saved_errno;
reset_signal_arrived ();
incyg = false;
sig = 0; /* Flag that we can accept another signal */
unlock (); /* unlock signal stack */
/* no ucontext_t information provided yet, so third arg is NULL */
thisfunc (thissig, &thissi, NULL);
thisfunc (thissig, &thissi, &thiscontext);
incyg = true;
set_signal_mask (_my_tls.sigmask, this_oldmask);