2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1994-2008, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure
5 * Copyright (C) 1991-3 Stephen Crane
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * See files README, COPYING and CREDITS in the root of the source
24 * tree for related information and legal notices. It is expected
25 * that future projects/authors will amend these files as needed.
29 * arch.c: architecture-dependant process context code
31 * Known contributors to this file:
33 * Steve McClure, 1994-2000
34 * Markus Armbruster, 2004-2007
44 * Historically, this was implemented by abusing setjmp() and
45 * longjump(), which required a fair amount of system-dependent and
46 * fragile hackery. We now use POSIX ucontext.h.
50 lwpNewContext(struct lwpProc *newp, int stacksz)
55 /* Make size a multiple of sizeof(long) to keep things aligned */
56 stacksz = (stacksz + sizeof(long) - 1) & -sizeof(long);
57 /* Add a red zone on each side of the stack for LWP_STACKCHECK */
58 redsize = newp->flags & LWP_STACKCHECK ? LWP_REDZONE : 0;
59 size = stacksz + 2 * redsize;
67 newp->ustack = s + redsize;
68 newp->usize = stacksz;
70 if (getcontext(&newp->context) < 0) {
74 #ifdef MAKECONTEXT_SP_HIGH
76 * Known systems that are broken that way: Solaris prior to 10,
79 newp->context.uc_stack.ss_sp = newp->ustack + stacksz - 8;
81 newp->context.uc_stack.ss_sp = newp->ustack;
83 newp->context.uc_stack.ss_size = newp->usize;
84 newp->context.uc_stack.ss_flags = 0;
85 newp->context.uc_link = NULL;
86 makecontext(&newp->context, lwpEntryPoint, 0);
91 lwpSwitchContext(struct lwpProc *oldp, struct lwpProc *nextp)
94 setcontext(&nextp->context);
97 if (swapcontext(&oldp->context, &nextp->context) < 0)