/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1994-2006, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1994-2011, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Ken Stevens, Steve McClure, Markus Armbruster
* Copyright (C) 1991-3 Stephen Crane
*
- * This program is free software; you can redistribute it and/or modify
+ * Empire is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* ---
*
* ---
*
* arch.c: architecture-dependant process context code
- *
+ *
* Known contributors to this file:
* Dave Pare, 1994
* Steve McClure, 1994-2000
- * Markus Armbruster, 2004-2006
+ * Markus Armbruster, 2004-2008
*/
#include <config.h>
#include <stdlib.h>
-#include "lwp.h"
#include "lwpint.h"
/*
- * Implement machine-dependent functions lwpNewContext(),
- * lwpSwitchContext().
- */
-
-
-#if defined UCONTEXT
-
-/*
- * Alternate aproach using setcontext and getcontext instead of setjmp
- * and longjump. This should work on any SVr4 machine independant of
- * architecture.
+ * Historically, this was implemented by abusing setjmp() and
+ * longjump(), which required a fair amount of system-dependent and
+ * fragile hackery. We now use POSIX ucontext.h.
*/
int
-lwpNewContext(struct lwpProc *newp, int stacksz)
+lwpNewContext(struct lwpProc *newp)
{
- char *s;
- int size, redsize;
-
- /* Make size a multiple of sizeof(long) to keep things aligned */
- stacksz = (stacksz + sizeof(long) - 1) & -sizeof(long);
- /* Add a red zone on each side of the stack for LWP_STACKCHECK */
- redsize = newp->flags & LWP_STACKCHECK ? LWP_REDZONE : 0;
- size = stacksz + 2 * redsize;
-
- s = malloc(size);
- if (!s)
+ if (getcontext(&newp->context) < 0)
return -1;
-
- newp->sbtm = s;
- newp->size = size;
- newp->ustack = s + redsize;
- newp->usize = stacksz;
-
- if (getcontext(&newp->context) < 0) {
- free(s);
- return -1;
- }
#ifdef MAKECONTEXT_SP_HIGH
/*
* Known systems that are broken that way: Solaris prior to 10,
* IRIX.
*/
- newp->context.uc_stack.ss_sp = newp->ustack + stacksz - 8;
+ newp->context.uc_stack.ss_sp = newp->ustack + newp->usize - 8;
#else
newp->context.uc_stack.ss_sp = newp->ustack;
#endif
abort();
}
}
-
-#else /* !UCONTEXT */
-
-/*
- * If lwpSave() and lwpRestore() are #def'd to setjmp() and longjmp(),
- * then lwpInitContext() needs to set up the jmp_buf for a longjmp(),
- * similar to setjmp(). To figure that out for another machine, check
- * their source or reverse engineer.
- */
-
-#if defined(hpc)
-
-#define STKALIGN 64
-
-static struct lwpProc *tempcontext;
-static struct lwpProc *initcontext = NULL;
-static int startpoint;
-
-static void
-startcontext(void)
-{
- int space[10000];
- int x;
-
- startpoint = (void *)&x;
- if (!setjmp(initcontext->context))
- longjmp(tempcontext->context, 1);
-
- if (!setjmp(tempcontext->context))
- longjmp(LwpCurrent->context, 1);
-
- lwpEntryPoint();
-}
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
- struct lwpProc holder;
- int endpoint;
-
- if (initcontext == NULL) {
- initcontext = malloc(sizeof(struct lwpProc));
- tempcontext = &holder;
- if (!setjmp(tempcontext->context))
- startcontext();
- }
-
- tempcontext = newp;
- endpoint = &endpoint;
- if (endpoint < startpoint) {
- if (!setjmp(LwpCurrent->context))
- longjmp(initcontext->context, 1);
- } else {
- LwpCurrent->size = endpoint - startpoint;
- LwpCurrent->sbtm = realloc(LwpCurrent->sbtm, LwpCurrent->size);
- memcpy(LwpCurrent->sbtm, startpoint, LwpCurrent->size);
- if (!setjmp(LwpCurrent->context))
- longjmp(initcontext->context, 1);
- memcpy(startpoint, LwpCurrent->sbtm, LwpCurrent->size);
- }
-}
-
-static int
-lwpSave(jmp_buf jb)
-{
- int endpoint;
-
- endpoint = &endpoint;
- if (initcontext == NULL || endpoint < startpoint)
- return setjmp(jb, 1);
-
- LwpCurrent->size = endpoint - startpoint;
- LwpCurrent->sbtm = realloc(LwpCurrent->sbtm, LwpCurrent->size);
- memcpy(LwpCurrent->sbtm, startpoint, LwpCurrent->size);
- if (setjmp(jb, 1)) {
- memcpy(startpoint, LwpCurrent->sbtm, LwpCurrent->size);
- return 1;
- }
- return 0;
-}
-
-#elif defined(hpux)
-
-#define STKALIGN 64
-
-static void
-lwpInitContext(volatile struct lwpProc *volatile newp, void *sp)
-{
- static jmp_buf *cpp;
-
- if (!lwpSave(LwpCurrent->context)) {
- cpp = (jmp_buf *)&newp->context;
- asm volatile ("ldw %0, %%sp"::"o" (sp));
- if (!lwpSave(*cpp))
- lwpRestore(LwpCurrent->context);
- lwpEntryPoint();
- }
-}
-
-static int
-lwpSave(jmp_buf jb)
-{
- /* save stack pointer and return program counter */
- asm("stw %sp, 4(%arg0)");
- asm("stw %rp, 8(%arg0)");
-
- /* save "callee save" registers */
- asm("stw %r3, 12(%arg0)");
- asm("stw %r4, 16(%arg0)");
- asm("stw %r5, 20(%arg0)");
- asm("stw %r6, 24(%arg0)");
- asm("stw %r7, 28(%arg0)");
- asm("stw %r8, 32(%arg0)");
- asm("stw %r9, 36(%arg0)");
- asm("stw %r10, 40(%arg0)");
- asm("stw %r11, 44(%arg0)");
- asm("stw %r12, 48(%arg0)");
- asm("stw %r13, 52(%arg0)");
- asm("stw %r14, 56(%arg0)");
- asm("stw %r15, 60(%arg0)");
- asm("stw %r16, 64(%arg0)");
- asm("stw %r17, 68(%arg0)");
- asm("stw %r18, 72(%arg0)");
-
- /* save "callee save" space register */
- asm volatile ("mfsp %sr3, %r1");
- asm("stw %r1, 0(%arg0)");
-
- /* indicate "true return" from saved() */
- asm("ldi 0, %ret0");
-
- asm(".LABEL _comefrom_");
-}
-
-static void
-lwpRestore(jmp_buf jb)
-{
- /* restore stack pointer and program counter */
- asm volatile ("ldw 4(%arg0), %sp");
- asm volatile ("ldw 8(%arg0), %rp");
-
- /* restore "callee save" space register */
- asm volatile ("ldw 0(%arg0), %r1");
- asm volatile ("mtsp %r1, %sr3");
-
- /* restore "callee save" registers */
- asm volatile ("ldw 12(%arg0), %r3");
- asm volatile ("ldw 16(%arg0), %r4");
- asm volatile ("ldw 20(%arg0), %r5");
- asm volatile ("ldw 24(%arg0), %r6");
- asm volatile ("ldw 28(%arg0), %r7");
- asm volatile ("ldw 32(%arg0), %r8");
- asm volatile ("ldw 36(%arg0), %r9");
- asm volatile ("ldw 40(%arg0), %r10");
- asm volatile ("ldw 44(%arg0), %r11");
- asm volatile ("ldw 48(%arg0), %r12");
- asm volatile ("ldw 52(%arg0), %r13");
- asm volatile ("ldw 56(%arg0), %r14");
- asm volatile ("ldw 60(%arg0), %r15");
- asm volatile ("ldw 64(%arg0), %r16");
- asm volatile ("ldw 68(%arg0), %r17");
- asm volatile ("ldw 72(%arg0), %r18");
-
- /* warp to saved() to unwind the frame correctly */
- asm volatile ("bl _comefrom_, %r0");
- asm volatile ("ldi 1, %ret0");
-}
-
-#elif defined(FBSD)
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
- setjmp(newp->context);
- newp->context->_jb[2] = (int)sp;
- newp->context->_jb[3] = (int)sp;
- newp->context->_jb[0] = (int)lwpEntryPoint;
-}
-
-#elif defined(__linux__)
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
-#if defined(__GLIBC__) && (__GLIBC__ >= 2)
-#if defined(__PPC__)
- newp->context->__jmpbuf[JB_GPR1] = (int)sp;
- newp->context->__jmpbuf[JB_LR] = (int)lwpEntryPoint;
-#else
- newp->context->__jmpbuf[JB_SP] = (int)sp;
- newp->context->__jmpbuf[JB_BP] = (int)sp;
- newp->context->__jmpbuf[JB_PC] = (int)lwpEntryPoint;
-#endif
-#else
- newp->context->__sp = sp;
- newp->context->__bp = sp;
- newp->context->__pc = (void *)lwpEntryPoint;
-#endif
-}
-
-#elif defined(SUN3)
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
- newp->context[2] = (int)sp;
- newp->context[3] = (int)lwpEntryPoint;
-}
-
-#elif defined(SUN4)
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
- static jmp_buf *cpp;
-
- memset(newp->context, 0, sizeof(newp->context));
- newp->context[0] = (int)sp;
- /* preserve cpp for new context */
- cpp = (jmp_buf *) & newp->context;
- if (!_setjmp(LwpCurrent->context)) {
- /* create new context */
- /* flush registers */
- asm("ta 0x03");
- /* %o0 <- newp */
- asm("ld [%fp+0x44], %o0");
- /* %o1 <- newp->context[0] */
- asm("ld [%o0], %o1");
- /* create min frame on new stack */
- asm("save %o1,-96, %sp");
- if (!_setjmp(*cpp))
- _longjmp(LwpCurrent->context, 1);
- lwpEntryPoint();
- }
-}
-
-#define lwpSave(x) _setjmp(x)
-#define lwpRestore(x) _longjmp(x, 1)
-
-#elif defined(ALPHA)
-
-#include <c_asm.h>
-
-static void
-lwpInitContext(struct lwpProc *newp, void *sp)
-{
- extern long *_gp;
-
- /* register values obtained from setjmp.h */
- _setjmp(newp->context);
- newp->context[2] = (long)lwpEntryPoint; /* program counter */
- newp->context[30] = (long)lwpEntryPoint; /* return address */
- newp->context[31] = (long)lwpEntryPoint; /* fake program value (!) */
- newp->context[34] = (long)sp; /* stack pointer */
-}
-
-static int
-lwpSave(jmp_buf jb)
-{
- return _setjmp(jb);
-}
-
-static void
-lwpRestore(jmp_buf jb)
-{
- /* resume, but get the pv from the jmp_buf */
- asm("ldq %pv, 248(%a0)");
- asm("stq %a0, 16(%sp)");
- /* generates a warning, but functions just fine */
- asm("bsr %ra, __longjump_resume");
-}
-
-#elif defined(AIX32)
-
-#define LWP_EXTRASTACK 12
-
-/* Code is in .s files, as compiler doesn't grok asm */
-extern int lwpSave(jmp_buf);
-extern void lwpRestore(jmp_buf);
-extern void lwpInitContext(struct lwpProc *);
-
-#endif
-
-#ifndef LWP_EXTRASTACK
-#define LWP_EXTRASTACK 0
-#endif
-#ifndef STKALIGN
-#define STKALIGN sizeof(double)
-#endif
-#ifndef lwpSave
-#define lwpSave(x) setjmp(x)
-#endif
-#ifndef lwpRestore
-#define lwpRestore(x) longjmp(x, 1)
-#endif
-
-int
-lwpNewContext(struct lwpProc *newp, int stacksz)
-{
- char *s, *sp;
- int size, redsize;
-
- if (CANT_HAPPEN(STKALIGN == 0|| (STKALIGN & (STKALIGN - 1))))
- return -1; /* STKALIGN not power of 2 */
-
- /* Make size a multiple of sizeof(long) to keep things aligned */
- stacksz = (stacksz + sizeof(long) - 1) & -sizeof(long);
- /* Add a red zone on each side of the stack for LWP_STACKCHECK */
- redsize = newp->flags & LWP_STACKCHECK ? LWP_REDZONE : 0;
- size = stacksz + 2 * redsize + LWP_EXTRASTACK + STKALIGN - 1;
-
- s = malloc(size);
- if (!s)
- return -1;
-
- if (LwpStackGrowsDown) {
- /*
- * Stack layout for stack growing downward:
- * ptr block size
- * --------------------------------------
- * red zone LWP_REDZONE
- * sp -> extra LWP_EXTRASTACK
- * ustack -> stack stacksz
- * red zone LWP_REDZONE
- * waste STKALIGN - 1 - x
- * sp is aligned to a multiple of STKALIGN.
- */
- sp = s + redsize + stacksz;
- sp = (char *)0 + (((sp + STKALIGN - 1) - (char *)0) & -STKALIGN);
- newp->ustack = sp - stacksz;
- } else {
- /*
- * Stack layout for stack growing upward:
- * ptr block size
- * --------------------------------------
- * waste x
- * red zone LWP_REDZONE
- * sp -> stack stacksz
- * ustack -> extra LWP_EXTRASTACK
- * red zone LWP_REDZONE
- * waste STKALIGN - 1 - x
- * sp is aligned to a multiple of STKALIGN.
- */
- sp = s + redsize + LWP_EXTRASTACK;
- sp = (char *)0 + (((sp + STKALIGN - 1) - (char *)0) & -STKALIGN);
- newp->ustack = sp - LWP_EXTRASTACK;
- }
- newp->sbtm = s;
- newp->size = size;
- newp->usize = stacksz + LWP_EXTRASTACK;
- lwpInitContext(newp, sp);
- return 0;
-}
-
-void
-lwpSwitchContext(struct lwpProc *oldp, struct lwpProc *nextp)
-{
- if (!(oldp && lwpSave(oldp->context)))
- lwpRestore(nextp->context);
-}
-
-#endif /* !UCONTEXT */