/* * 0 >= bytes write * -1 = invalid args * -2 = no message */ int P2_MboxCondReceive(int mbox, void *msg, int *size){ if(mbox < 0 || mbox >= P2_MAX_MBOX || mailboxes[mbox].inUse != 1 || permissionCheck()){ return -1; } mailbox *cur = &(mailboxes[mbox]); P1_P(cur->mutex); if(cur->activeSlots != 0){ P1_P(cur->fulls); //Never blocks message *m = queuePop(&(cur->queue)); int retVal = 0; if(*size > m->bufSize){ retVal = m->bufSize; }else{ retVal = *size; } memcpy(msg,m->buf,retVal); free(m->buf); free(m); cur->activeSlots--; P1_V(cur->mutex); P1_V(cur->empties); return retVal; } P1_V(cur->mutex); return -2; }
int P2_MboxRelease(int mbox){ if(permissionCheck()){ return -1; } P1_P(mBoxSemaphore); int i; for(i = 0; i < P2_MAX_MBOX;i++){ if(mailboxes[i].inUse && mailboxes[i].id == mbox){ if(P1_SemFree(mailboxes[i].mutex) != 0){ USLOSS_Console("Processes waiting on mailbox. Halting.\n"); USLOSS_Halt(1); } if(P1_SemFree(mailboxes[i].fulls) != 0){ USLOSS_Console("Processes waiting on mailbox. Halting.\n"); USLOSS_Halt(1); } if(P1_SemFree(mailboxes[i].empties) != 0){ USLOSS_Console("Processes waiting on mailbox. Halting.\n"); USLOSS_Halt(1); } while(mailboxes[i].queue != NULL){ message *m = queuePop(&(mailboxes[i].queue)); free(m->buf); free(m); } mailboxes[i].inUse = 0; P1_V(mBoxSemaphore); return 0; } } P1_V(mBoxSemaphore); return -1; }
int P2_MboxSend(int mbox, void *msg, int *size){ if(mbox < 0 || mbox >= P2_MAX_MBOX || mailboxes[mbox].inUse != 1 || mailboxes[mbox].maximumMessageSize < *size || permissionCheck()){ return -1; } mailbox *cur = &(mailboxes[mbox]); P1_P(cur->empties); P1_P(cur->mutex); void *m = malloc(*size); memcpy(m,msg,*size); queueInsert(m,*size,&(cur->queue)); cur->activeSlots++; P1_V(cur->mutex); P1_V(cur->fulls); return 0; }
int semDelete(int id){ P1_P(semGuard); int ret = P1_SemFree(userSemList[id].sem); userSemList[id].inUse = 0; P1_V(semGuard); return ret; }
int P2_MboxCreate(int slots, int size){ if(permissionCheck()){ return -1; } P1_P(mBoxSemaphore); if(slots <= 0 || size < 0){ P1_V(mBoxSemaphore); return -2; } int i; for(i = 0; i < P2_MAX_MBOX;i++){ if(mailboxes[i].inUse == 0){ mailboxes[i].inUse = 1; mailboxes[i].maxSlots = slots; mailboxes[i].maximumMessageSize = size; mailboxes[i].mutex = P1_SemCreate(1); mailboxes[i].empties = P1_SemCreate(slots); mailboxes[i].fulls = P1_SemCreate(0); mailboxes[i].queue = NULL; mailboxes[i].activeSlots = 0; P1_V(mBoxSemaphore); return i; } } P1_V(mBoxSemaphore); return -1; }
int P1_WaitDevice(int type, int unit, int *status){ if(procTable[currPid].state==2){//Checks if killed return -3; } /*TO DO: Check If valid Unit*/ if(unit<0||unit>3){ return -1; } Semaphore* sema; switch(type){ case USLOSS_CLOCK_INT: if(unit!=1){ return -1; } USLOSS_WaitInt(); *status=-1; break; case USLOSS_ALARM_INT: if(unit!=1){ return -1; } sema=&semTable[Alarm_Sema]; P1_P(sema); *status=-1; break; case USLOSS_DISK_INT: if(unit<1||unit>2){ return -1; } sema=&semTable[Disk_Sema]; P1_P(sema); *status=-1; break; case USLOSS_TERM_INT: if(unit<1||unit>4){ return -1; } sema=&semTable[Term_Sema]; P1_P(sema); *status=-1; break; default: return -2;//Invalid Type } return 0; }
int child_p(void *arg){ USLOSS_Console("start child_p\n"); P1_P(sem); //P1_DumpProcesses(); USLOSS_Console("end child_p\n"); return 666; }
int validSem(int id){ P1_P(semGuard); if(id < 0 || id >= P1_MAXSEM){ P1_V(semGuard); return 0; } P1_V(semGuard); return userSemList[id].inUse == 1; }
int P2_Startup(void *arg){ USLOSS_Console(" \n---------Starting Test 7 ----------\n"); int childpid = P1_Fork("child", child, NULL, USLOSS_MIN_STACK * 4, 2); sem1 = P1_SemCreate(-1); P1_P(sem1); USLOSS_Console(" %d \n", 1); USLOSS_Console(" ---------Ending Test 7 ----------\n"); P1_Quit(0); }
int P2_Sleep(int seconds){ if(permissionCheck() || seconds < 0){ return -1; } P1_Semaphore s = P1_SemCreate(0); P1_P(clockListSemaphore); int i; for(i = 0; i < P1_MAXPROC;i++){ if(clockList[i].inUse == 0){ clockList[i].inUse = 1; clockList[i].sem = s; clockList[i].startTime = USLOSS_Clock(); clockList[i].waitingTime = seconds * US_IN_S; break; } } P1_V(clockListSemaphore); P1_P(s); P1_SemFree(s); return 0; }
int semAdd(P1_Semaphore s){ int i; P1_P(semGuard); for(i = 0; i < P1_MAXSEM;i++){ if(userSemList[i].inUse == 0){ userSemList[i].inUse = 1; userSemList[i].sem = s; P1_V(semGuard); return i; } } P1_V(semGuard); return -1; }
void wakeUpProcesses(void){ P1_P(clockListSemaphore); int i; long now = USLOSS_Clock(); for(i = 0; i < P1_MAXPROC;i++){ if(clockList[i].inUse == 1){ if((now - clockList[i].startTime) >= clockList[i].waitingTime){ P1_V(clockList[i].sem); clockList[i].inUse = 0; } } } P1_V(clockListSemaphore); }
int TermDriver(void *arg){ int unit = (int) arg; termReaderMB[unit] = P2_MboxCreate(1,INT_SIZE); termLookAhead[unit] = P2_MboxCreate(10,MAX_LINE); termCharToWrite[unit] = P2_MboxCreate(1,INT_SIZE); termWriteSem[unit] = P1_SemCreate(1); termRunningSem[unit] = P1_SemCreate(0); P1_Fork("Term Reader", TermReader, (void *) unit,USLOSS_MIN_STACK, 2); P1_P(termRunningSem[unit]); /*Turn on Terminal interrupts*/ int ctrl = 0; int ctrl2 = 0; ctrl = USLOSS_TERM_CTRL_RECV_INT(ctrl); USLOSS_DeviceOutput(USLOSS_TERM_DEV,unit,(void *)ctrl); P1_V(running); int status = 0; int c = 0; int result; while(1){ result = P1_WaitDevice(USLOSS_TERM_DEV,unit,&status); if(result != 0 || done != 0){ break; } if(USLOSS_TERM_STAT_RECV(status) == USLOSS_DEV_BUSY){ P2_MboxSend(termReaderMB[unit],&status,&INT_SIZE); } if(USLOSS_TERM_STAT_XMIT(status) == USLOSS_DEV_READY){ if(P2_MboxCondReceive(termCharToWrite[unit],&c,&INT_SIZE) != -2){ ctrl2 = 0; ctrl2 = USLOSS_TERM_CTRL_XMIT_INT(ctrl2); ctrl2 = USLOSS_TERM_CTRL_RECV_INT(ctrl2); ctrl2 = USLOSS_TERM_CTRL_CHAR(ctrl2, c); ctrl2 = USLOSS_TERM_CTRL_XMIT_CHAR(ctrl2); USLOSS_DeviceOutput(USLOSS_TERM_DEV, unit, (void *)ctrl2); }else{ ctrl2 = 0; ctrl2 = USLOSS_TERM_CTRL_RECV_INT(ctrl2); USLOSS_DeviceOutput(USLOSS_TERM_DEV, unit, (void *)ctrl2); } } } status = 0; P2_MboxCondSend(termReaderMB[unit],&ctrl,&status); P1_Join(&status); return unit; }
/*P2_DiskSize() returns info about the size of the disk indicated by unit*/ int P2_DiskSize(int unit, int *sector, int *track, int *disk) { if(permissionCheck() || unit < 0 || unit > 1){ return -1; } P1_P(diskSem[unit]); int status; *sector = USLOSS_DISK_SECTOR_SIZE; *track = USLOSS_DISK_TRACK_SIZE; // Make device request for finding number of tracks in disk USLOSS_DeviceRequest request; request.opr = USLOSS_DISK_TRACKS; //reg1 contains pointer to integer where number of disk tracks will be stored request.reg1 = disk; USLOSS_DeviceOutput(USLOSS_DISK_DEV,unit,&request); P1_WaitDevice(USLOSS_DISK_DEV,unit,&status); P1_V(diskSem[unit]); return 0; }
//write a 512 byte sector to the current track int P2_DiskWrite(int unit, int track, int first, int sectors, void *buffer) { if(permissionCheck() || track < 0 || track >= DISK_TRACKS[unit] || first < 0 || first > 15 || unit < 0 || unit > 1 || sectors <= 0){ return -1; } P1_P(diskSem[unit]); int status = 0; //first make a device request struct for a seek USLOSS_DeviceRequest seekRequest; seekRequest.opr = USLOSS_DISK_SEEK; seekRequest.reg1 = (void *)track; //track number where the r/w head should be moved //make device request struct for write USLOSS_DeviceRequest writeRequest; writeRequest.opr = USLOSS_DISK_WRITE; USLOSS_DeviceOutput(USLOSS_DISK_DEV,unit,&seekRequest); P1_WaitDevice(USLOSS_DISK_DEV,unit,&status); int i = 0; while (sectors != 0 && status == 0) { writeRequest.reg1 = (void *)first; writeRequest.reg2 = buffer + (i * USLOSS_DISK_SECTOR_SIZE); USLOSS_DeviceOutput(USLOSS_DISK_DEV,unit,&writeRequest); P1_WaitDevice(USLOSS_DISK_DEV,unit,&status); if (status == USLOSS_DEV_ERROR) { USLOSS_Console("Error with disk write request, unit %d, track %d, sector %d\n",unit, track, first); } first++; sectors--; if (first == 16 && sectors > 0) { //need to move on to next track. track++; seekRequest.reg1 = (void *) track; USLOSS_DeviceOutput(USLOSS_DISK_DEV,unit,&seekRequest); P1_WaitDevice(USLOSS_DISK_DEV,unit,&status); first = 0; //set first to 0 sector of new track } writeRequest.reg1 = (void *)first; i++; } P1_V(diskSem[unit]); return status; }
/*Join: Causes current Process to wait for first child to quit*/ int P1_Join(int *status){ Check_Your_Privilege(); if(procTable[currPid].numChildren == 0){ return -1; } int i; /*get the PID of the child that quit*/ P1_Semaphore sema = &semTable[currPid]; // USLOSS_Console("Join:Before P\n"); P1_P(sema); // USLOSS_Console("Join:After P\n"); for( i= 0; i < P1_MAXPROC; i++){ if(procTable[i].parent==currPid&&procTable[i].state==3){ *status=procTable[i].status; procTable[currPid].numChildren--; removeProc(i); return i; } } return -2; }
int P2_TermWrite(int unit, int size, char *text){ if(unit >= USLOSS_TERM_UNITS || unit < 0 || size < 0){ return -1; } int ctrl = 0; if(size > P2_MAX_LINE){ size = P2_MAX_LINE; } P1_P(termWriteSem[unit]); int i = 0; int cSize = sizeof(char); int c; while(i < size){ ctrl = USLOSS_TERM_CTRL_XMIT_INT(0); ctrl = USLOSS_TERM_CTRL_RECV_INT(ctrl); USLOSS_DeviceOutput(USLOSS_TERM_DEV, unit, (void *)ctrl); c = *(text + i); P2_MboxSend(termCharToWrite[unit],&c,&cSize); i++; } P1_V(termWriteSem[unit]); P2_Sleep(1); return size; }
int P2_Startup(void *arg) { USLOSS_IntVec[USLOSS_SYSCALL_INT] = sysHandler; /*Init all mailboxes*/ int i; for(i = 0; i < P2_MAX_MBOX;i++){ mailboxes[i].id = i; mailboxes[i].inUse = 0; mailboxes[i].queue = NULL; mailboxes[i].activeSlots = 0; } for(i = 0; i < P1_MAXPROC;i++){ clockList[i].inUse = 0; } for(i = 0; i < P1_MAXSEM;i++){ userSemList[i].id = i; userSemList[i].inUse = 0; } mBoxSemaphore = P1_SemCreate(1); clockListSemaphore = P1_SemCreate(1); semGuard = P1_SemCreate(1); running = P1_SemCreate(0); int status; int pid; int clockPID; /* * Create clock device driver */ clockPID = P1_Fork("Clock driver", ClockDriver, (void *) running, USLOSS_MIN_STACK, 2); if (clockPID == -1) { USLOSS_Console("Can't create clock driver\n"); } /* * Wait for the clock driver to start. */ P1_P(running); for(i = 0; i < USLOSS_TERM_UNITS;i++){ termPids[i] = P1_Fork("Term driver", TermDriver, (void *) i,USLOSS_MIN_STACK, 2); if (termPids[i] == -1) { USLOSS_Console("Can't create term driver. Unit = %d\n",i); } P1_P(running); } int sector,track,disk; for (i = 0; i < USLOSS_DISK_UNITS;i++) { diskSem[i] = P1_SemCreate(1); P2_DiskSize(i,§or,&track,&disk); DISK_TRACKS[i] = disk; } pid = P2_Spawn("P3_Startup", P3_Startup, NULL, 4 * USLOSS_MIN_STACK, 3); pid = P2_Wait(&status); /* * Kill the device drivers */ P1_Kill(clockPID); /*Let everyone know we are done.*/ done = 1; /*Interrupt all terminals*/ int ctrl = 0; ctrl = USLOSS_TERM_CTRL_XMIT_INT(ctrl); ctrl = USLOSS_TERM_CTRL_RECV_INT(ctrl); for(i = 0 ; i < USLOSS_TERM_UNITS;i++){ P1_Kill(termPids[i]); USLOSS_DeviceOutput(USLOSS_TERM_DEV, i, (void *)ctrl); P2_Wait(&status); } /*Interrupt any disk requests*/ USLOSS_DeviceRequest seekRequest; seekRequest.opr = USLOSS_DISK_SEEK; seekRequest.reg1 = (void *)0; for(i = 0 ; i < USLOSS_DISK_UNITS;i++){ USLOSS_DeviceOutput(USLOSS_DISK_DEV,i,(void *)&seekRequest); P2_Wait(&status); } /*Finally wait for the clock driver to be done*/ P2_Wait(&status); return 0; }
void sysHandler(int type,void *arg) { if(arg == NULL){ USLOSS_Console("USLOSS_Sysargs is NULL!\n"); return; } USLOSS_Sysargs *sysArgs = (USLOSS_Sysargs *) arg; int retVal = 0; int retVal2 = 0; int sectSize = 0; int sectors = 0; int tracks = 0; interruptsOn(); switch (sysArgs->number) { case SYS_TERMREAD: retVal = P2_TermRead((int)sysArgs->arg3, (int)sysArgs->arg2, sysArgs->arg1); if(retVal >= 0){ sysArgs->arg4 = (void *)0; sysArgs->arg2 = (void *)retVal; }else{ sysArgs->arg4 = (void *)-1; } break; case SYS_TERMWRITE: retVal = P2_TermWrite((int)sysArgs->arg3,(int)sysArgs->arg2,(char *)sysArgs->arg1); if(retVal >= 0){ sysArgs->arg4 = (void *)0; sysArgs->arg2 = (void *)retVal; }else{ sysArgs->arg4 = (void *)-1; } break; case SYS_SPAWN: //Part 1 retVal = P2_Spawn(sysArgs->arg5, sysArgs->arg1, sysArgs->arg2, (int) sysArgs->arg3, (int) sysArgs->arg4); if (retVal == -3 || retVal == -2) { sysArgs->arg4 = (void *) -1; sysArgs->arg1 = (void *) -1; } else { sysArgs->arg1 = (void *) retVal; sysArgs->arg4 = (void *) 0; } break; case SYS_WAIT: //Part 1 retVal = P2_Wait(&retVal2); if(retVal == -1){ sysArgs->arg1 = (void *)-1; sysArgs->arg4 = (void *)-1; sysArgs->arg2 = (void *)-1; }else{ sysArgs->arg1 = (void *)retVal; sysArgs->arg2 = (void *)retVal2; sysArgs->arg4 = (void *)0; } break; case SYS_TERMINATE: //Part 1 P2_Terminate((int)sysArgs->arg1); break; case SYS_SLEEP: // Part 1 retVal = P2_Sleep((int)sysArgs->arg1); sysArgs->arg4 = (void *) retVal; break; case SYS_DISKREAD: retVal = P2_DiskRead((int)sysArgs->arg5,(int)sysArgs->arg3,(int) sysArgs->arg4,(int)sysArgs->arg2,(void *)sysArgs->arg1); if (retVal == -1) { sysArgs->arg1 = (void *)retVal; sysArgs->arg4 = (void *)-1; } else if (retVal == 0) { sysArgs->arg1 = (void *)0; sysArgs->arg4 = (void *)0; }else { sysArgs->arg1 = (void *)retVal; //output is the disk's status register sysArgs->arg4 = (void *)0; } break; case SYS_DISKWRITE: retVal = P2_DiskWrite((int)sysArgs->arg5,(int)sysArgs->arg3,(int) sysArgs->arg4,(int)sysArgs->arg2,(void *)sysArgs->arg1); if (retVal == -1) { sysArgs->arg1 = (void *)retVal; sysArgs->arg4 = (void *)-1; } else if (retVal == 0) { sysArgs->arg1 = (void *)0; sysArgs->arg4 = (void *)0; }else { sysArgs->arg1 = (void *)retVal; //output is the disk's status register sysArgs->arg4 = (void *)0; } break; case SYS_DISKSIZE: retVal = P2_DiskSize((int)sysArgs->arg1,§Size,§ors,&tracks); if (retVal == -1) { sysArgs->arg4 = (void *)-1; }else { sysArgs->arg4 = (void *)0; sysArgs->arg1 = (void *)sectSize; sysArgs->arg2 = (void *)sectors; sysArgs->arg3 = (void *)tracks; } break; case SYS_GETTIMEOFDAY: //Part 1 sysArgs->arg1 = (void *)USLOSS_Clock(); break; case SYS_CPUTIME: //Part 1 sysArgs->arg1 = (void *)P1_ReadTime(); break; case SYS_DUMPPROCESSES: //Part 1 P1_DumpProcesses(); break; case SYS_GETPID: //Part 1 sysArgs->arg1 = (void *) P1_GetPID(); break; case SYS_SEMCREATE: //Part 1 retVal = (int)sysArgs->arg1; if(retVal < 0){ sysArgs->arg4 = (void *)-1; }else{ sysArgs->arg4 = (void *)0; sysArgs->arg1 = (void *) semAdd(P1_SemCreate(retVal)); } break; case SYS_SEMP: // Part 1 if(validSem((int)sysArgs->arg1) == 0){ sysArgs->arg4 = (void *) -1; return; } retVal = P1_P(userSemList[(int)sysArgs->arg1].sem); if(retVal < 0){ sysArgs->arg4 = (void *) -1; } else{ sysArgs->arg4 = (void *) 0; } break; case SYS_SEMV: // Part 1 if(validSem((int)sysArgs->arg1) == 0){ sysArgs->arg4 = (void *) -1; return; } retVal = P1_V(userSemList[(int)sysArgs->arg1].sem); if(retVal < 0){ sysArgs->arg4 = (void *) -1; } else{ sysArgs->arg4 = (void *) 0; } break; case SYS_SEMFREE: // Part 1 if(validSem((int)sysArgs->arg1) == 0){ sysArgs->arg4 = (void *) -1; return; } retVal = semDelete((int)sysArgs->arg1); if(retVal < 0){ sysArgs->arg4 = (void *) -1; } else{ sysArgs->arg4 = (void *) 0; } break; case SYS_MBOXCREATE: //Part 1 retVal = P2_MboxCreate((int)sysArgs->arg1,(int)sysArgs->arg2); if(retVal == -2){ sysArgs->arg1 = (void *) -1; sysArgs->arg4 = (void *) -1; }else{ sysArgs->arg1 = (void *) retVal; sysArgs->arg4 = (void *) 0; } break; case SYS_MBOXRELEASE: // Part 1 retVal = P2_MboxRelease((int)sysArgs->arg1); if(retVal < 0){ sysArgs->arg4 = (void *) -1; }else{ sysArgs->arg4 = (void *) 0; } break; case SYS_MBOXSEND: // Part 1 retVal = P2_MboxSend((int)sysArgs->arg1,sysArgs->arg2,(int *)&sysArgs->arg3); if(retVal < 0){ sysArgs->arg4 = (void *) -1; }else{ sysArgs->arg4 = (void *) 0; } break; case SYS_MBOXRECEIVE: // Part 1 retVal = P2_MboxReceive((int)sysArgs->arg1,sysArgs->arg2,(int *)&sysArgs->arg3); if(retVal < 0){ sysArgs->arg4 = (void *) -1; }else{ sysArgs->arg4 = (void *) 0; sysArgs->arg2 = (void *) retVal; } break; case SYS_MBOXCONDSEND: // Part 1 retVal = P2_MboxCondSend((int)sysArgs->arg1,sysArgs->arg2,(int *)&sysArgs->arg3); if(retVal == -1){ sysArgs->arg4 = (void *) -1; }else if(retVal == -2){ sysArgs->arg4 = (void *) 1; } else{ sysArgs->arg4 = (void *) 0; } break; case SYS_MBOXCONDRECEIVE: // Part 1 retVal = P2_MboxCondReceive((int)sysArgs->arg1,sysArgs->arg2,(int *)&sysArgs->arg3); if(retVal == -1){ sysArgs->arg4 = (void *) -1; }else if(retVal == -2){ sysArgs->arg4 = (void *) 1; } else{ sysArgs->arg4 = (void *) 0; sysArgs->arg2 = (void *) retVal; } break; default: P1_Quit(1); } }