CS Operating System Project

#include <stdio.h> #include <unistd.h> #include <errno.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/sem.h> #include "sem.h" typedef struct sem_ds sDType; typedef struct seminfo sIType; typedef struct sembuf sBType; typedef union { int val; sDType *buf; const unsigned short int *array; sIType *__buf; } sUType; typedef struct { sUType arg; sBType zero; sBType lock; sBType unlock; long sID; pid_t pID; } iNType; static void setSB ( sBType * const s, const int sN, const int sO, const int sF ) { s->sem_num = sN; s->sem_op = sO; s->sem_flg = sF; } void initSEM ( void * const v, const long k ) { const long kY = k; iNType *const iP = (iNType* const)v; sBType *const sZ = &iP->zero; sBType *const sL = &iP->lock; sBType *const sU = &iP->unlock; setSB (sZ,0,0,SEM_UNDO); setSB (sL,0,-1,SEM_UNDO); setSB (sU,0,1,SEM_UNDO); iP->pID = getpid(); iP->sID = semget(kY,1, IPC_CREAT| IPC_EXCL| 0666); if(iP->sID == -1) iP->sID = semget (kY,1,0); setSEM (0,v); } const int getSSizeSEM() { const int s = sizeof(iNType); return s; } const int pSEM ( void * const v ) { iNType *const iP = (iNType* const)v; const int sid = iP->sID; sBType *const sL = &iP->lock; const int eC = semop(sid, sL, 1); return eC; } const int setSEM ( const int x, void * const v ) { iNType *const iP = (iNType* const)v; const int sid = iP->sID; semctl (sid,0,SETVAL, x); } void vSEM ( void * const v ) { iNType *const iP = (iNType* const)v; const int sid = iP->sID; sBType *const sU = &iP->unlock; semop (sid, sU, 1); } void zSEM ( void * const v ) { iNType *const iP = (iNType* const)v; const int sid = iP->sID; sBType *const sZ = &iP->zero; semop (sid, sZ, 1); } void dSEM ( void * const v ) { iNType *const iP = (iNType* const)v; const int p1 = getpid(); const int p2 = iP->pID; const long p3 = iP->sID; if(p1==p2) semctl(p3,0, IPC_RMID,0); }