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/*
**************************************************************************
*
* Component =
*
* Synopsis = rdbg/i386/excep.c
*
**************************************************************************
*/
#include <rtems.h>
#include <rtems/error.h>
#include <rdbg/rdbg_f.h>
#include <assert.h>
#include <errno.h>
#include <rdbg/rdbg.h>
#include <rdbg/servrpc.h>
extern rtems_id serializeSemId;
extern rtems_id wakeupEventSemId;
unsigned int NbExceptCtx;
volatile unsigned int NbSerializedCtx;
Exception_context *FirstCtx = NULL;
Exception_context *LastCtx = NULL;
CPU_Exception_frame SavedContext;
/********* Save an exception context at the end of a list *****/
int PushExceptCtx ( Objects_Id Id, Objects_Id semId, CPU_Exception_frame *ctx ) {
Exception_context *SaveCtx;
SaveCtx = (Exception_context *)malloc(sizeof(Exception_context));
if (SaveCtx == NULL)
rtems_panic("Can't allocate memory to save Exception context");
SaveCtx->id = Id;
SaveCtx->ctx = ctx;
SaveCtx->semaphoreId = semId;
SaveCtx->previous = NULL;
SaveCtx->next = NULL;
if (FirstCtx == NULL){ /* initialization */
FirstCtx = SaveCtx;
LastCtx = SaveCtx;
NbExceptCtx = 1;
}
else {
NbExceptCtx ++;
LastCtx->next = SaveCtx;
SaveCtx->previous = LastCtx;
LastCtx = SaveCtx;
}
return 0;
}
/********* Save an temporary exception context in a ******/
/********* global variable ******/
int PushSavedExceptCtx ( Objects_Id Id, CPU_Exception_frame *ctx ) {
memcpy (&(SavedContext), ctx, sizeof(CPU_Exception_frame));
return 0;
}
/****** Remove the context of the specified Id thread *********/
/****** If Id = -1, then return the first context *********/
int PopExceptCtx ( Objects_Id Id ) {
Exception_context *ExtractCtx;
if (FirstCtx == NULL) return -1;
if (Id == -1) {
ExtractCtx = LastCtx;
LastCtx = LastCtx->previous;
free(ExtractCtx);
NbExceptCtx --;
return 0;
}
ExtractCtx = LastCtx;
while (ExtractCtx->id != Id && ExtractCtx != NULL) {
ExtractCtx = ExtractCtx->previous;
}
if (ExtractCtx == NULL)
return -1;
if ( ExtractCtx->previous != NULL)
(ExtractCtx->previous)->next = ExtractCtx->next;
if ( ExtractCtx->next != NULL)
(ExtractCtx->next)->previous = ExtractCtx->previous;
if (ExtractCtx == FirstCtx)
FirstCtx = FirstCtx->next;
else
if (ExtractCtx == LastCtx)
LastCtx = LastCtx->previous;
free(ExtractCtx);
NbExceptCtx --;
return 0;
}
/****** Return the context of the specified Id thread *********/
/****** If Id = -1, then return the first context *********/
Exception_context *GetExceptCtx ( Objects_Id Id ) {
Exception_context *ExtractCtx;
if (FirstCtx == NULL) return NULL;
if (Id == -1) {
return LastCtx;
}
ExtractCtx = LastCtx;
while (ExtractCtx->id != Id && ExtractCtx != NULL) {
ExtractCtx = ExtractCtx->previous;
}
if (ExtractCtx == NULL)
return NULL;
return ExtractCtx;
}
/*----- Breakpoint Exception management -----*/
/*
* Handler for Breakpoint Exceptions :
* software breakpoints.
*/
void
BreakPointExcHdl(CPU_Exception_frame *ctx)
{
rtems_status_code status;
rtems_id continueSemId;
if ( (justSaveContext) && (ctx->idtIndex == I386_EXCEPTION_ENTER_RDBG) ) {
PushSavedExceptCtx (_Thread_Executing->Object.id, ctx);
justSaveContext = 0;
}
else {
if (ctx->idtIndex != I386_EXCEPTION_DEBUG){
NbSerializedCtx++;
rtems_semaphore_obtain(serializeSemId, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
NbSerializedCtx--;
}
currentTargetThread = _Thread_Executing->Object.id;
#ifdef DDEBUG
printk("----------------------------------------------------------\n");
printk("Exception %d caught at PC %x by thread %d\n",
ctx->idtIndex,
ctx->eip,
_Thread_Executing->Object.id);
printk("----------------------------------------------------------\n");
printk("Processor execution context at time of the fault was :\n");
printk("----------------------------------------------------------\n");
printk(" EAX = %x EBX = %x ECX = %x EDX = %x\n",
ctx->eax, ctx->ebx, ctx->ecx, ctx->edx);
printk(" ESI = %x EDI = %x EBP = %x ESP = %x\n",
ctx->esi, ctx->edi, ctx->ebp, ctx->esp0);
printk("----------------------------------------------------------\n");
printk("Error code pushed by processor itself (if not 0) = %x\n",
ctx->faultCode);
printk("----------------------------------------------------------\n\n");
#endif
status = rtems_semaphore_create (rtems_build_name('D', 'B', 'G', 'c'),
0,
RTEMS_FIFO |
RTEMS_COUNTING_SEMAPHORE |
RTEMS_NO_INHERIT_PRIORITY |
RTEMS_NO_PRIORITY_CEILING |
RTEMS_LOCAL,
0,
&continueSemId);
if (status != RTEMS_SUCCESSFUL)
rtems_panic ("Can't create continue semaphore: `%s'\n",rtems_status_text(status));
PushExceptCtx (_Thread_Executing->Object.id, continueSemId, ctx);
switch (ctx->idtIndex){
case I386_EXCEPTION_DEBUG:
DPRINTF((" DEBUG EXCEPTION !!!\n"));
ctx->eflags &= ~EFLAGS_TF;
ExitForSingleStep-- ;
rtems_semaphore_release( wakeupEventSemId );
break;
case I386_EXCEPTION_BREAKPOINT:
DPRINTF((" BREAKPOINT EXCEPTION !!!\n"));
rtems_semaphore_release( wakeupEventSemId );
break;
case I386_EXCEPTION_ENTER_RDBG:
DPRINTF((" ENTER RDBG !!!\n"));
rtems_semaphore_release( wakeupEventSemId );
break;
default:
DPRINTF((" OTHER EXCEPTION !!!\n"));
rtems_semaphore_release( wakeupEventSemId );
break;
}
rtems_semaphore_obtain(continueSemId, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
PopExceptCtx (_Thread_Executing->Object.id);
rtems_semaphore_delete(continueSemId);
}
}
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