michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "prlog.h"
michael@0: #include "prthread.h"
michael@0: #include "private/pprthred.h"
michael@0: #include "primpl.h"
michael@0: 
michael@0: PR_IMPLEMENT(PRWord *)
michael@0: PR_GetGCRegisters(PRThread *t, int isCurrent, int *np)
michael@0: {
michael@0:     return _MD_HomeGCRegisters(t, isCurrent, np);
michael@0: }
michael@0: 
michael@0: PR_IMPLEMENT(PRStatus)
michael@0: PR_ThreadScanStackPointers(PRThread* t,
michael@0:                            PRScanStackFun scanFun, void* scanClosure)
michael@0: {
michael@0:     PRThread* current = PR_GetCurrentThread();
michael@0:     PRWord *sp, *esp, *p0;
michael@0:     int n;
michael@0:     void **ptd;
michael@0:     PRStatus status;
michael@0:     PRUint32 index;
michael@0:     int stack_end;
michael@0: 
michael@0:     /*
michael@0:     ** Store the thread's registers in the thread structure so the GC
michael@0:     ** can scan them. Then scan them.
michael@0:     */
michael@0:     p0 = _MD_HomeGCRegisters(t, t == current, &n);
michael@0:     status = scanFun(t, (void**)p0, n, scanClosure);
michael@0:     if (status != PR_SUCCESS)
michael@0:         return status;
michael@0: 
michael@0:     /* Scan the C stack for pointers into the GC heap */
michael@0: #if defined(XP_PC) && defined(WIN16)
michael@0:     /*
michael@0:     ** Under WIN16, the stack of the current thread is always mapped into
michael@0:     ** the "task stack" (at SS:xxxx).  So, if t is the current thread, scan
michael@0:     ** the "task stack".  Otherwise, scan the "cached stack" of the inactive
michael@0:     ** thread...
michael@0:     */
michael@0:     if (t == current) {
michael@0:         sp  = (PRWord*) &stack_end;
michael@0:         esp = (PRWord*) _pr_top_of_task_stack;
michael@0: 
michael@0:         PR_ASSERT(sp <= esp);
michael@0:     } else {
michael@0:         sp  = (PRWord*) PR_GetSP(t);
michael@0:         esp = (PRWord*) t->stack->stackTop;
michael@0: 
michael@0:         PR_ASSERT((t->stack->stackSize == 0) ||
michael@0:                   ((sp >  (PRWord*)t->stack->stackBottom) &&
michael@0:                    (sp <= (PRWord*)t->stack->stackTop)));
michael@0:     }
michael@0: #else   /* ! WIN16 */
michael@0: #ifdef HAVE_STACK_GROWING_UP
michael@0:     if (t == current) {
michael@0:         esp = (PRWord*) &stack_end;
michael@0:     } else {
michael@0:         esp = (PRWord*) PR_GetSP(t);
michael@0:     }
michael@0:     sp = (PRWord*) t->stack->stackTop;
michael@0:     if (t->stack->stackSize) {
michael@0:         PR_ASSERT((esp > (PRWord*)t->stack->stackTop) &&
michael@0:                   (esp < (PRWord*)t->stack->stackBottom));
michael@0:     }
michael@0: #else   /* ! HAVE_STACK_GROWING_UP */
michael@0:     if (t == current) {
michael@0:         sp = (PRWord*) &stack_end;
michael@0:     } else {
michael@0:         sp = (PRWord*) PR_GetSP(t);
michael@0:     }
michael@0:     esp = (PRWord*) t->stack->stackTop;
michael@0:     if (t->stack->stackSize) {
michael@0:         PR_ASSERT((sp > (PRWord*)t->stack->stackBottom) &&
michael@0:                   (sp < (PRWord*)t->stack->stackTop));
michael@0:     }
michael@0: #endif  /* ! HAVE_STACK_GROWING_UP */
michael@0: #endif  /* ! WIN16 */
michael@0: 
michael@0: #if defined(WIN16)
michael@0:     {
michael@0:         prword_t scan;
michael@0:         prword_t limit;
michael@0:         
michael@0:         scan = (prword_t) sp;
michael@0:         limit = (prword_t) esp;
michael@0:         while (scan < limit) {
michael@0:             prword_t *test;
michael@0: 
michael@0:             test = *((prword_t **)scan);
michael@0:             status = scanFun(t, (void**)&test, 1, scanClosure);
michael@0:             if (status != PR_SUCCESS)
michael@0:                 return status;
michael@0:             scan += sizeof(char);
michael@0:         }
michael@0:     }
michael@0: #else
michael@0:     if (sp < esp) {
michael@0:         status = scanFun(t, (void**)sp, esp - sp, scanClosure);
michael@0:         if (status != PR_SUCCESS)
michael@0:             return status;
michael@0:     }
michael@0: #endif
michael@0: 
michael@0:     /*
michael@0:     ** Mark all of the per-thread-data items attached to this thread
michael@0:     **
michael@0:     ** The execution environment better be accounted for otherwise it
michael@0:     ** will be collected
michael@0:     */
michael@0:     status = scanFun(t, (void**)&t->environment, 1, scanClosure);
michael@0:     if (status != PR_SUCCESS)
michael@0:         return status;
michael@0: 
michael@0:     /* if thread is not allocated on stack, this is redundant. */
michael@0:     ptd = t->privateData;
michael@0:     for (index = 0; index < t->tpdLength; index++, ptd++) {
michael@0:         status = scanFun(t, (void**)ptd, 1, scanClosure);
michael@0:         if (status != PR_SUCCESS)
michael@0:             return status;
michael@0:     }
michael@0:     
michael@0:     return PR_SUCCESS;
michael@0: }
michael@0: 
michael@0: /* transducer for PR_EnumerateThreads */
michael@0: typedef struct PRScanStackData {
michael@0:     PRScanStackFun      scanFun;
michael@0:     void*               scanClosure;
michael@0: } PRScanStackData;
michael@0: 
michael@0: static PRStatus PR_CALLBACK
michael@0: pr_ScanStack(PRThread* t, int i, void* arg)
michael@0: {
michael@0:     PRScanStackData* data = (PRScanStackData*)arg;
michael@0:     return PR_ThreadScanStackPointers(t, data->scanFun, data->scanClosure);
michael@0: }
michael@0: 
michael@0: PR_IMPLEMENT(PRStatus)
michael@0: PR_ScanStackPointers(PRScanStackFun scanFun, void* scanClosure)
michael@0: {
michael@0:     PRScanStackData data;
michael@0:     data.scanFun = scanFun;
michael@0:     data.scanClosure = scanClosure;
michael@0:     return PR_EnumerateThreads(pr_ScanStack, &data);
michael@0: }
michael@0: 
michael@0: PR_IMPLEMENT(PRUword)
michael@0: PR_GetStackSpaceLeft(PRThread* t)
michael@0: {
michael@0:     PRThread *current = PR_GetCurrentThread();
michael@0:     PRWord *sp, *esp;
michael@0:     int stack_end;
michael@0: 
michael@0: #if defined(WIN16)
michael@0:     /*
michael@0:     ** Under WIN16, the stack of the current thread is always mapped into
michael@0:     ** the "task stack" (at SS:xxxx).  So, if t is the current thread, scan
michael@0:     ** the "task stack".  Otherwise, scan the "cached stack" of the inactive
michael@0:     ** thread...
michael@0:     */
michael@0:     if (t == current) {
michael@0:         sp  = (PRWord*) &stack_end;
michael@0:         esp = (PRWord*) _pr_top_of_task_stack;
michael@0: 
michael@0:         PR_ASSERT(sp <= esp);
michael@0:     } else {
michael@0:         sp  = (PRWord*) PR_GetSP(t);
michael@0:         esp = (PRWord*) t->stack->stackTop;
michael@0: 
michael@0: 	PR_ASSERT((t->stack->stackSize == 0) ||
michael@0:                  ((sp >  (PRWord*)t->stack->stackBottom) &&
michael@0: 		  (sp <= (PRWord*)t->stack->stackTop)));
michael@0:     }
michael@0: #else   /* ! WIN16 */
michael@0: #ifdef HAVE_STACK_GROWING_UP
michael@0:     if (t == current) {
michael@0:         esp = (PRWord*) &stack_end;
michael@0:     } else {
michael@0:         esp = (PRWord*) PR_GetSP(t);
michael@0:     }
michael@0:     sp = (PRWord*) t->stack->stackTop;
michael@0:     if (t->stack->stackSize) {
michael@0:         PR_ASSERT((esp > (PRWord*)t->stack->stackTop) &&
michael@0:                   (esp < (PRWord*)t->stack->stackBottom));
michael@0:     }
michael@0: #else   /* ! HAVE_STACK_GROWING_UP */
michael@0:     if (t == current) {
michael@0:         sp = (PRWord*) &stack_end;
michael@0:     } else {
michael@0:         sp = (PRWord*) PR_GetSP(t);
michael@0:     }
michael@0:     esp = (PRWord*) t->stack->stackTop;
michael@0:     if (t->stack->stackSize) {
michael@0: 	PR_ASSERT((sp > (PRWord*)t->stack->stackBottom) &&
michael@0: 		  (sp < (PRWord*)t->stack->stackTop));
michael@0:     }
michael@0: #endif  /* ! HAVE_STACK_GROWING_UP */
michael@0: #endif  /* ! WIN16 */
michael@0:     return (PRUword)t->stack->stackSize - ((PRWord)esp - (PRWord)sp);
michael@0: }