extern void trapMemory(ExceptionStackFrame *exceptionStackFrame)
{
TracePrintf(512, "trapMemory: vector(%d), code(%d), addr(%d), psr(%d), pc(%d), sp(%d), regs(%s)\n",
exceptionStackFrame->vector, exceptionStackFrame->code, exceptionStackFrame->addr,
exceptionStackFrame->psr, exceptionStackFrame->pc, exceptionStackFrame->sp,
exceptionStackFrame->regs);
if( exceptionStackFrame -> addr > current -> stack_brk )
{
TracePrintf(0, "Trap Memory Error: addr: %d is large than stack_brk: %d\n", exceptionStackFrame -> addr, current -> stack_brk);
//Exit;
}
if( exceptionStackFrame -> addr < UP_TO_PAGE(current -> heap_brk) + PAGESIZE )
{
TracePrintf(0, "Trap Memory Error: addr: %d is smaller than heap_brk: %d\n", exceptionStackFrame -> addr, current -> heap_brk);
//Exit;
}
long userTablePTE;
TracePrintf(510, "Moving user stack down to address: %d (%d)\n", exceptionStackFrame -> addr, (long)exceptionStackFrame -> addr >> PAGESHIFT);
for (userTablePTE = (DOWN_TO_PAGE(exceptionStackFrame -> addr)); userTablePTE < (DOWN_TO_PAGE(current -> stack_brk)); userTablePTE += PAGESIZE)
{
unsigned int i = ((userTablePTE) >> PAGESHIFT) % PAGE_TABLE_LEN;
UserPageTable[i].valid = 1;
UserPageTable[i].uprot = PROT_NONE;
UserPageTable[i].kprot = PROT_READ | PROT_WRITE;
/* Need to change the pfn here */
UserPageTable[i].pfn = allocatePhysicalPage();
TracePrintf(250, "Allocate physical pages for user process: PID(%d), VPN(%d), PFN(%d).\n", current -> PID, i, UserPageTable[i].pfn);
}
}
void DoDelay(UserContext *context) {
TracePrintf(1, "in DoDelay\n");
current_process->clock_count = context->regs[0];
TracePrintf(1, "Delay: %d\n", context->regs[0]);
DelayAdd(current_process);
LoadNextProc(context, BLOCK);
}
void LoadNextProc(UserContext *context, int block) {
DelayPop();
if (!queueIsEmpty(ready_queue)) {
if (current_process) {
current_process->user_context = *context;
if (block == NO_BLOCK) {
queuePush(ready_queue, current_process);
}
}
PCB *next = queuePop(ready_queue);
TracePrintf(1, "LoadNextProc: Next Process Id: %d\n", next->id);
if(next->id == 2)
TracePrintf(3, "LoadNextProc: PCB has %p child\n", next->parent->children->head);
WriteRegister(REG_PTBR1, (unsigned int) &(next->cow.pageTable));
WriteRegister(REG_TLB_FLUSH, TLB_FLUSH_1);
KernelContextSwitch(MyKCS, current_process, next);
TracePrintf(1, "LoadNextProc: Got past MyKCS\n");
*context = current_process->user_context;
TracePrintf(3, "LoadNextProc: current user context pc is %p\n", context->pc);
}
}
/* This function make perfect mapping from kernel virtual memory phyical memory
*/
void init_kernel_page_table() {
kernel_page_table = (pte_t*) malloc(sizeof(pte_t) * GET_PAGE_NUMBER(VMEM_0_SIZE));
// For text segment mapping
TracePrintf(0, "Text Start=%p, End=%p\n", kernel_memory.text_low, kernel_memory.data_low);
write_kernel_pte(kernel_memory.text_low, kernel_memory.data_low
, _VALID, PROT_READ | PROT_EXEC);
// For data segment mapping
TracePrintf(0, "Data Start=%p, End=%p\n", kernel_memory.data_low, kernel_memory.brk_low);
write_kernel_pte(kernel_memory.data_low, kernel_memory.brk_low
, _VALID, PROT_READ | PROT_WRITE);
// For stack segment mapping, noted that stack space is reserved even if it is not used
TracePrintf(0, "Stack Start=%p, End=%p\n", KERNEL_STACK_BASE, KERNEL_STACK_LIMIT);
write_kernel_pte(KERNEL_STACK_BASE, KERNEL_STACK_LIMIT
, _VALID, PROT_READ | PROT_WRITE);
int i;
// Add free pages between heap and stack
int start_pfn = GET_PAGE_NUMBER(UP_TO_PAGE(kernel_memory.brk_high));
int end_pfn = GET_PAGE_NUMBER(DOWN_TO_PAGE(KERNEL_STACK_BASE));
for(i = start_pfn; i < end_pfn; i++) {
add_tail_available_frame(i);
}
// Add free pages above kernel space
start_pfn = GET_PAGE_NUMBER(UP_TO_PAGE(VMEM_0_LIMIT));
end_pfn = GET_PAGE_NUMBER(DOWN_TO_PAGE(PMEM_BASE)) + PAGE_SIZE;
for(i = start_pfn; i < end_pfn; i++) {
add_tail_available_frame(i);
}
}
void DoLockInit(UserContext *context) {
if (BufferCheck(context->regs[0], INT_LENGTH) == ERROR || BufferWriteCheck(context->regs[0], INT_LENGTH) == ERROR) {
TracePrintf(1, "DoLockInit: Pointer given not valid. Returning Error\n");
context->regs[0] = ERROR;
return;
}
Lock *lock = malloc(sizeof(Lock));
if (lock == NULL) {
TracePrintf(2, "CreateLock, malloc error\n");
context->regs[0] = ERROR;
return;
}
lock->waiting = queueNew();
if (lock->waiting == NULL) {
TracePrintf(2, "CreateLock: malloc error\n");
context->regs[0] = ERROR;
return;
}
lock->cvars = 0;
int lock_id = lock_count * NUM_RESOURCE_TYPES + LOCK;
lock_count++;
lock->id = lock_id;
*((int *) context->regs[0]) = lock_id;
queuePush(locks, lock);
context->regs[0] = SUCCESS;
}
extern int KernelBrk(void *addr, struct PCBNode *pcb)
{
TracePrintf(256, "Brk: addr(%d)\n", addr);
//check if the addr is illegal
if(addr < MEM_INVALID_SIZE)
{
TracePrintf(0, "Error in KernelBrk: Trying to set the brk below MEM_INVALID_SIZE.\n");
//Exit the program.
}
if(addr > DOWN_TO_PAGE(pcb -> stack_brk) - PAGESIZE)
{
TracePrintf(0, "Error in KernelBrk: Trying to set the brk inside or above the red zone.\n");
}
unsigned int userTablePTE;
//Only allocate for entire pages??
unsigned int gap = (UP_TO_PAGE(addr)-UP_TO_PAGE(pcb -> heap_brk));
if(gap>0)
{
TracePrintf(250, "Moving user brk up to address: %d (%d)\n", addr, (long)addr >> PAGESHIFT);
for (userTablePTE = (UP_TO_PAGE(pcb -> heap_brk)); userTablePTE < (UP_TO_PAGE(addr)); userTablePTE += PAGESIZE)
{
unsigned int i = ((userTablePTE) >> PAGESHIFT) % PAGE_TABLE_LEN;
UserPageTable[i].valid = 1;
UserPageTable[i].uprot = PROT_NONE;
UserPageTable[i].kprot = PROT_READ | PROT_WRITE;
/* Need to change the pfn here */
UserPageTable[i].pfn = allocatePhysicalPage();
TracePrintf(250, "Allocate physical pages for user process: PID(%d), VPN(%d), PFN(%d).\n", pcb -> PID, i, UserPageTable[i].pfn);
}
}
extern int KernelFork(void)
{
TracePrintf(256, "Fork\n");
struct PCBNode cur_active = *active_process;
struct PCBNode* newproc = malloc(sizeof(struct PCBNode));
if(newproc == NULL) return ERROR;
newproc = (struct PCBNode *)malloc(sizeof(struct PCBNode));
newproc -> PID = nextPID();
//will need to change this thing later
newproc -> pageTable = malloc(PAGE_TABLE_LEN * sizeof(struct pte));
newproc -> status = READY;
newproc -> blockedReason = 0;
newproc -> numTicksRemainForDelay = 0;
newproc -> parent = NULL;
newproc -> child = NULL;
newproc -> prevSibling = NULL;
newproc -> nextSibling = NULL;
TracePrintf(100, "Fork enter context switch\n");
ContextSwitch(forkSwitchFunc, &(cur_active.ctxp), &cur_active, newproc);
TracePrintf(100, "Fork left context switch\n");
if(cur_active.PID == active_process->PID){
//return from parent
return newproc->PID;
}else{
//this is returning from child, which means we should maintain the child queue
return 0;
}
return 0;
}
void DoWait(UserContext *context) {
if (BufferCheck(context->regs[0], INT_LENGTH) == ERROR || BufferWriteCheck(context->regs[0], INT_LENGTH) == ERROR) {
TracePrintf(1, "DoWait: Pointer given not valid. Returning Error\n");
context->regs[0] = ERROR;
return;
}
if (queueIsEmpty(current_process->children) && queueIsEmpty(current_process->deadChildren)) {
TracePrintf(2, "DoWait: PCB %d Has no children. Returning Error.\n", current_process->id);
TracePrintf(2, "DoWait: Children queue count: %d, deadChildren count: %d\n", current_process->children->length, current_process->deadChildren->length);
context->regs[0] = ERROR;
} else {
if (queueIsEmpty(current_process->deadChildren)) {
current_process->status = WAITING;
queuePush(wait_queue, current_process);
LoadNextProc(context, BLOCK);
}
ZCB *child = queuePop(current_process->deadChildren);
queueRemove(process_queue, child);
*((int *)context->regs[0]) = child->status;
context->regs[0] = child->id;
}
}
int main(int argc, char *argv[]) {
TracePrintf(1, "\t===>Start: tty.c.c\n");
char write_msg[] = "Hello World!";
int size = sizeof(write_msg);
int rc;
rc = Fork();
if (rc == 0) {
Pause();
Pause();
Pause();
Pause();
TtyWrite(1, write_msg, size);
TracePrintf(1, "\t===>tty.c: Just wrote to terminal 1.\n");
return 0;
} else {
char read_msg[10];
size = sizeof(read_msg);
TtyRead(2, read_msg, size);
TracePrintf(1, "\t===>tty.c: Just read from terminal 2: %s.\n", read_msg);
}
TracePrintf(1, "\t===>End: tty.c.c\n");
return 0;
}
void DoIdle(void) {
while(1) {
TracePrintf(0, "********************************************************************************\n");
TracePrintf(0, "*************************** DoIlde is running! *******************************\n");
TracePrintf(0, "********************************************************************************\n");
Pause();
}
}
int
queueIsEmpty(Queue *queue) {
TracePrintf(4, "queueIsEmpty: queue->head = %p, queue->length = %d\n", queue->head, queue->length);
if (queue->head == NULL) {
TracePrintf(4, "queueIsEmpty: queue is empty\n");
}
return (queue->head == NULL);
}
// Print error message and kill proc
void TrapIllegal(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapIllegal(%p)\n", user_context);
char *err_str = calloc(TERMINAL_MAX_LINE, sizeof(char));
sprintf(err_str, "TRAP_ILLEGAL exception for proc %d\n", current_proc->pid);
KernelTtyWriteInternal(0, err_str, strnlen(err_str, TERMINAL_MAX_LINE), user_context);
free(err_str);
KernelExit(ERROR, user_context);
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapIllegal(%p)\n", user_context);
}
// Get a copy of the currently running Kernel Context and save it in the current pcb
KernelContext *SaveCurrentKernelContext(KernelContext *kernel_context, void *current_pcb,
void *next_pcb) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> SaveCurrentKernelContext()\n");
((PCB*) current_pcb)->kernel_context = *kernel_context;
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< SaveCurrentKernelContext()\n");
return kernel_context;
}
void TrapTtyRecieve(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapTtyRecieve(%p)\n", user_context);
int tty_id = user_context->code;
// Find the proper terminal struct
Tty term = ttys[tty_id];
if (ListEmpty(term.waiting_to_receive)) {
// no waiting procs, so create line buffer and
// add to list
LineBuffer *lb = calloc(1, sizeof(LineBuffer));
lb->buffer = calloc(TERMINAL_MAX_LINE, sizeof(char));
lb->length = TtyReceive(tty_id, lb->buffer, TERMINAL_MAX_LINE);
ListEnqueue(term.line_buffers, lb, 0);
} else {
// at least one proc waiting
// create heap in kernel to use
char *input = calloc(TERMINAL_MAX_LINE, sizeof(char));
char *input_ptr = input; // point how far into the buffer we've read
int input_length = TtyReceive(tty_id, input, TERMINAL_MAX_LINE);
int input_remaining = input_length;
// Continue so long as procs are waiting and there is unconsumed input
while (!ListEmpty(term.waiting_to_receive) && input_remaining > 0) {
PCB *waiting_proc = (PCB *) ListDequeue(term.waiting_to_receive);
assert(waiting_proc->tty_receive_buffer);
// put proc back into ready queue
ListAppend(ready_queue, waiting_proc, waiting_proc->pid);
if (input_remaining <= waiting_proc->tty_receive_len) {
// Consuming all the input
memcpy(waiting_proc->tty_receive_buffer, input_ptr, input_remaining);
waiting_proc->tty_receive_len = input_remaining;
input_remaining = 0;
} else {
// Only consuming some of the input
memcpy(waiting_proc->tty_receive_buffer, input_ptr, waiting_proc->tty_receive_len);
input_remaining -= waiting_proc->tty_receive_len;
input_ptr += waiting_proc->tty_receive_len;
}
}
// Check if there is still input left after all the procs have been filled
if (input_remaining > 0) {
// Create new line buffer and store
char *remaining_buff = calloc(input_remaining, sizeof(char));
memcpy(remaining_buff, input_ptr, input_remaining);
LineBuffer *lb = calloc(1, sizeof(LineBuffer));
lb->buffer = remaining_buff;
lb->length = input_remaining;
ListEnqueue(term.line_buffers, lb, 0);
}
free(input);
}
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapTtyRecieve(%p)\n", user_context);
}
// Print message and kill
void TrapMath(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapMath(%p)\n", user_context);
TracePrintf(TRACE_LEVEL_NON_TERMINAL_PROBLEM, "Killing proc on trap math \n");
char *err_str = calloc(TERMINAL_MAX_LINE, sizeof(char));
sprintf(err_str, "TRAP_MATH exception for proc %d\n", current_proc->pid);
KernelTtyWriteInternal(0, err_str, strnlen(err_str, TERMINAL_MAX_LINE), user_context);
free(err_str);
KernelExit(ERROR, user_context);
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapMath(%p)\n", user_context);
}
void DoExec(UserContext *context) {
TracePrintf(5, "DoExec\n");
current_process->user_context = *context;
TracePrintf(5, "DoExec: LoadProgram\n");
int rc = LoadProgram(context->regs[0], context->regs[1], current_process);
TracePrintf(5, "DoExec: finished LoadProgram\n");
if (rc != SUCCESS) {
current_process->user_context.regs[0] = ERROR;
}
*context = current_process->user_context;
TracePrintf(5, "Finished DoExec\n");
}
void DoPS(UserContext *context) {
TracePrintf(3, "DoPS: In DoPS\n");
for (List *process = process_queue->head; process; process = process->next) {
if (((ZCB *) process->data)->status == DEAD) {
TracePrintf(1, "PID: %d. DEAD\n", ((ZCB *) process->data)->id);
} else {
TracePrintf(1, "PID: %d.\n", ((PCB *) process->data)->id);
}
}
context->regs[0] = SUCCESS;
return;
}
int main(int argc, char **argv) {
int i;
TracePrintf(-1, "In process %d\n", GetPid());
printf("In process %d\n", GetPid());
TracePrintf(-1, "%d arguments passed in\n", argc);
printf("%d arguments passed in\n", argc);
for (i = 0; i < argc; i++) {
TracePrintf(-1, "\targ %d is %s\n", i, argv[i]);
printf("\targ %d is %s\n", i, argv[i]);
}
return 0;
}
// Context switch to the next process in the ready queue.
// The next process's context will be loaded into the param user_context.
// NOTE: place the current proc into the correct queue before calling
// (e.g., ready queue, clock blocked queue)
void SwitchToNextProc(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> SwitchToNextProc()\n");
// Get the proc at the front of the queue
PCB *next_proc = ListDequeue(ready_queue);
if (next_proc) {
SwitchToProc(next_proc, user_context);
} else { // No procs waiting, so just switch to the idle proc
TracePrintf(TRACE_LEVEL_DETAIL_INFO, "No waiting procs, idling\n");
SwitchToProc(idle_proc, user_context);
}
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< SwitchToNextProc()\n");
}
int main(int argc, char *argv[]) {
TracePrintf(1, "\t===>pipe.c\n");
int pipe_id;
int rc;
if (PipeInit(&pipe_id) != 0)
TracePrintf(1, "Failed to initialize pipe\n");
else
TracePrintf(1, "Pipe Initialized. ID = %d\n", pipe_id);
rc = Fork();
if (rc == 0) {
char *to_write = (char *)malloc(5 * sizeof(char));
to_write[0] = 'a';
to_write[1] = 'b';
to_write[2] = 'c';
to_write[3] = 'd';
to_write[4] = 'e';
char *second_write = (char *)malloc(2 * sizeof(char));
second_write[0] = 'e';
second_write[1] = 'f';
int written;
Pause();
TracePrintf(1, "\tCHILD: about to write to the lock\n");
written = PipeWrite(pipe_id, to_write, 4);
TracePrintf(1, "\tCHILD: wrote %d characters to the lock\n", written);
Pause();
TracePrintf(1, "\tCHILD: pausing once\n");
Pause();
written = PipeWrite(pipe_id, second_write, 2);
TracePrintf(1, "\tCHILD: wrote to the pipe again (%d chars)\n", written);
Pause();
Exit(0);
} else {
char *to_read = (char *)malloc(6 * sizeof(char));
int read;
Pause();
Pause();
TracePrintf(1, "\tPARENT: reading 6 chars from the pipe (before it's ready\n");
read = PipeRead(pipe_id, to_read, 6);
TracePrintf(1, "\tPARENT: read %d chars from the pipe. Results: %s\n", read, to_read);
Pause();
Exit(0);
}
return 0;
}
// Method pased to ListMap on clock tick
// decrements the number of ticks remaining for each proc that is waiting from Delay
void DecrementTicksRemaining(void *_proc) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> DecrementTicksRemaining(%p)\n", _proc);
PCB *proc = (PCB *) _proc;
--proc->clock_ticks_until_ready;
if (proc->clock_ticks_until_ready <= 0) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO,
">>> DecrementTicksRemaining: proc %p done waiting!\n",
_proc);
ListRemoveById(clock_block_procs, proc->pid);
ListAppend(ready_queue, proc, proc->pid);
}
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< DecrementTicksRemaining()\n");
}
void TrapTtyTransmit(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapTtyTransmit(%p)\n", user_context);
int tty_id = user_context->code;
Tty term = ttys[tty_id];
assert(!ListEmpty(term.waiting_to_transmit));
// Get the currently transmitting proc (always at the front of the list)
PCB *waiting_proc = (PCB *) ListPeak(term.waiting_to_transmit);
if (waiting_proc->tty_transmit_len > TERMINAL_MAX_LINE) {
// not completely transmitted, so handle pointer stuff and leave in
// front of the queue
waiting_proc->tty_transmit_pointer += TERMINAL_MAX_LINE;
waiting_proc->tty_transmit_len -= TERMINAL_MAX_LINE;
// transmit min(MAX_LINE, len)
if (TERMINAL_MAX_LINE > waiting_proc->tty_transmit_len) {
TtyTransmit(tty_id, waiting_proc->tty_transmit_pointer,
waiting_proc->tty_transmit_len);
} else {
TtyTransmit(tty_id, waiting_proc->tty_transmit_pointer,
TERMINAL_MAX_LINE);
}
return;
}
// transmission complete
// since done, take off transmitting list
ListRemoveById(term.waiting_to_transmit, waiting_proc->pid);
ListAppend(ready_queue, waiting_proc, waiting_proc->pid);
free(waiting_proc->tty_transmit_buffer);
if (ListEmpty(term.waiting_to_transmit)) {
return; // no other procs waiting on this term
}
// Get the next proc waiting to submit
PCB *next_to_transmit = (PCB *) ListPeak(term.waiting_to_transmit);
// transmit min(MAX_LINE, len)
if (TERMINAL_MAX_LINE > next_to_transmit->tty_transmit_len) {
TtyTransmit(tty_id, next_to_transmit->tty_transmit_pointer,
next_to_transmit->tty_transmit_len);
} else {
TtyTransmit(tty_id, next_to_transmit->tty_transmit_pointer,
TERMINAL_MAX_LINE);
}
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapTtyTransmit(%p)\n", user_context);
}
int LockRelease(Lock *lock) {
if (lock == NULL) {
TracePrintf(2, "LockRelease: Lock not found.\n");
return ERROR;
} else if (lock->owner != current_process) {
TracePrintf(2, "LockRelease: Current process does not hold lock it is trying to release.\n");
return ERROR;
} else {
lock->owner = queuePop(lock->waiting);
if (lock->owner) {
queuePush(ready_queue, lock->owner);
}
return SUCCESS;
}
}
void main(void) {
int delay = 4;
int delays[512];
int delays2[1024];
//int delays3[1024 * 2];
//int delays4[1024 * 4];
//int delays5[1024 * 8];
while(1) {
TracePrintf(1, "GJJ is coding like a boss.\n");
// Delay(delay);
Pause();
}
TracePrintf(1, "GJJ leaving the init proc\n");
return;
}
void TrapClock(UserContext *user_context) {
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, ">>> TrapClock(%p)\n", user_context);
// Use Map interface to decrement the ticks remaining for each proc
ListMap(clock_block_procs, &DecrementTicksRemaining);
// If the current proc is not the idle, place it in the ready queue
if (current_proc->pid != IDLE_PID) {
ListAppend(ready_queue, current_proc, current_proc->pid);
}
// and switch to the next ready proc
SwitchToNextProc(user_context);
TracePrintf(TRACE_LEVEL_FUNCTION_INFO, "<<< TrapClock(%p)\n", user_context);
}
extern void trapIllegal(ExceptionStackFrame *exceptionStackFrame)
{
TracePrintf(512, "trapIllegal: vector(%d), code(%d), addr(%d), psr(%d), pc(%d), sp(%d), regs(%s)\n",
exceptionStackFrame->vector, exceptionStackFrame->code, exceptionStackFrame->addr,
exceptionStackFrame->psr, exceptionStackFrame->pc, exceptionStackFrame->sp,
exceptionStackFrame->regs);
int code = exceptionStackFrame->code;
char string[128];
char* msg = string;
if (code == ILL_BADSTK)
msg = "Bad stack\n";
else if (code == ILL_ILLOPC || code == ILL_ILLOPN || code == ILL_ILLADR)
msg = "Illegal instruction\n";
else if (code == ILL_PRVOPC || code == ILL_PRVREG)
msg = "Privileged instruction\n";
else if (code == ILL_COPROC)
msg = "Coprocessor error\n";
else if (code == ILL_ILLTRP)
msg = "Illegal software trap\n";
else if (code == BUS_ADRALN + 20)
printf(msg, "Invalid address alignment %p", exceptionStackFrame->addr);
else if (code == SI_KERNEL)
msg = "Linux kernel SIGILL\n";
else if (code == SI_USER)
msg = "Received SIGILL from user\n";
else
printf(msg, "Unknown code 0x%x", code);
//KernelExit(ERROR);
printf(msg);
}
void writeBridgeToPipe() {
int rc = PipeWrite(pipe_id, (void *) b, sizeof(Bridge));
if (rc != sizeof(Bridge)) {
TracePrintf(TRACE_LEVEL_TERMINAL_PROBLEM, "FAILED TO WRITE BRIDGE\n");
Exit(-1);
}
}
void DoSpoon(UserContext *context) {
// Get an available process id.
int newPid = pidCount++;
PCB *child = (PCB *)malloc(sizeof(PCB));
// If for any reason we can't fork, return ERROR to calling process.
if (!newPid || !child) {
context->regs[0] = ERROR;
return;
}
PCB_Init(child);
child->id = newPid;
child->parent = current_process;
queuePush(child->parent->children, child);
if (queueIsEmpty(child->parent->children))
TracePrintf(3, "DoSpoon: parent queue empty.\n");
child->status = RUNNING;
// Return 0 to child and arm the child for execution.
child->user_context = *context;
queuePush(ready_queue, child);
queuePush(process_queue, child);
KernelContextSwitch(SpoonKernel, current_process, child);
// Return child's pid to parent and resume execution of the parent.
if (current_process->id == newPid) {
*context = current_process->user_context;
context->regs[0] = 0;
} else {
context->regs[0] = newPid;
}
}
int main(int argc, char *argv[]) {
while (1) {
TracePrintf(1, "Do Init Prog!\n");
Pause();
}
return 0;
}
void DoExit(UserContext *context) {
if (1 == current_process->id) {
TracePrintf(1, "Do Exit: init program exiting. Now calling halt.\n");
Halt();
}
if (current_process->parent) {
current_process->status = context->regs[0];
}
TracePrintf(2, "DoExit\n");
KillProc(current_process);
TracePrintf(2, "DoExit: Finished the murder\n");
LoadNextProc(context, BLOCK);
}