//.cpp(主函数) #include <stdlib.h> #include <stdio.h> #include <memory.h> #include "sys.h" int num_SRC = 0; int num_PRO = 0; int *Availiable = NULL; int *work = NULL; int *finish = NULL; int **Max = NULL; int **Allocation = NULL; int **Need = NULL; int init(int n_SRC,int m_PRO) { int i = 0; num_PRO = m_PRO; num_SRC = n_SRC; /**/ Availiable = (int*)malloc(sizeof(int)*num_SRC); memset(Availiable,0,sizeof(int)*num_SRC); work = (int*)malloc(sizeof(int)*num_SRC); memset(work,0,sizeof(int)*num_SRC); finish = (int*)malloc(sizeof(int)*num_PRO); memset(finish,0,sizeof(int)*num_PRO); /**/ Max = (int**)malloc(sizeof(int*)*num_PRO); for(i=0;i<num_PRO;i++) { Max[i] = (int*)malloc(sizeof(int)*num_SRC); memset(Max[i],0,sizeof(int)*num_SRC); } /**/ Allocation = (int**)malloc(sizeof(int)*num_PRO); for(i=0;i<num_PRO;i++) { Allocation[i] = (int*)malloc(sizeof(int)*num_SRC); memset(Allocation[i],0,sizeof(int)*num_SRC); } /**/ Need = (int**)malloc(sizeof(int)*num_PRO); for(i=0;i<num_PRO;i++) { Need[i] = (int*)malloc(sizeof(int)*num_SRC); memset(Need[i],0,sizeof(int)*num_SRC); } return SUCCESS; } void SetVal(int *availiable,int **max,int **allocation) { int i,j; memcpy(Availiable,availiable,sizeof(int)*num_SRC); for(i=0;i<num_PRO;i++) { memcpy(Max[i],max[i],sizeof(int)*num_SRC); } for(i=0;i<num_PRO;i++) { memcpy(Allocation[i],allocation[i],sizeof(int)*num_SRC); } for(i=0;i<num_PRO;i++) { for(j=0;j<num_SRC;j++) { Need[i][j] = Max[i][j] - Allocation[i][j]; } } } int LegitimacyCheck(int PRO,int* Request) { int i = 0; for(i=0;i<num_SRC;i++) if(Request[i] > Availiable[i] || Request[i] > Need[PRO][i]) return ERROR; return SUCCESS; } void CopyToWork() { memcpy(work,Availiable,sizeof(int)*num_SRC); memset(finish,0,sizeof(int)*num_PRO); } int PreAllocation(int PRO,int* Request) { int i = 0; /*执行预分配*/ for (i=0;i<num_SRC;i++) { Availiable[i] -= Request[i]; Allocation[PRO][i] += Request[i]; Need[PRO][i] -= Request[i]; } return SUCCESS; } void RealAllocation(int process) { int i = 0; int flag = 0; /*执行预分配*/ for (i=0;i<num_SRC;i++) { if(Need[process][i] != 0) flag++; } if(flag == 0) { for (i=0;i<num_SRC;i++) { Availiable[i] += Allocation[process][i]; Allocation[process][i] = 0; Need[process][i] = 0; } } } int SafeContest() { int process = 0; int src = 0; int count = 1; CopyToWork(); while (count <= num_PRO) { int flag = 0;//计数器，用来记录某个进程不满足条件的资源数目，如果为0则说明全部满足条件 for (process=0;process<num_PRO;process++) { flag = 0; if(finish[process] != 0) continue; for (src=0;src<num_SRC;src++) { if (Need[process][src] > work[src]) flag++; } if(flag == 0)//当前进程满足finish = FALSE 且 对所有资源的需求量小于可分配的量 break; //此时退出循环，选定当前进程 } if(flag != 0)//如果没有进程满足条件，则状态不安全 break; else { for(src=0;src<num_SRC;src++)//如果有满足条件的进程，则进行试分配 { work[src] += Allocation[process][src]; } finish[process] = count; DisplayState(process); count++; } } if(count == num_PRO+1) { printf("当前状态安全，可分配,一个可行的安全序列为：\n"); return SUCCESS; } else { printf("当前状态不安全，不可分配\n"); return ERROR; } } void ReBack(int PRO,int* Request) { int i = 0; /*执行回收*/ for (i=0;i<num_SRC;i++) { Availiable[i] += Request[i]; Allocation[PRO][i] -= Request[i]; Need[PRO][i] += Request[i]; } } void DisplaySafeSeq() { int i = 0; int count = 1; while (count<=num_PRO) { for(i=0;i<num_PRO;i++) if(finish[i] == count) printf("%d ",i); count++; } printf("\n"); } void DisplayState(int process) { int i,j; printf("\n"); if (process != -1) printf("第%d号进程执行完后状态为：\n",process); printf("尚需数组:\n "); for(i=0;i<num_SRC;i++) { printf("- ",i); } printf("\n"); for(i=0;i<num_PRO;i++) { printf("%d ",i); if(finish[i] != 0 && process != -1) for(j=0;j<num_SRC;j++) printf("%d ",j); else for(j=0;j<num_SRC;j++) printf("- ",Need[i][j]); printf("\n"); } printf("已分配资源数组:\n "); for(i=0;i<num_SRC;i++) { printf("- ",i); } printf("\n"); for(i=0;i<num_PRO;i++) { printf("%d ",i); if(finish[i] != 0 && process != -1) for(j=0;j<num_SRC;j++) printf(" %d ",j); else printf("- ",Allocation[i][j]); printf("\n"); } printf("可用资源数组："); for(i=0;i<num_SRC;i++) if (process == -1) printf("%d ",Availiable[i]); else printf("%d ",work[i]); printf("\n"); }
//main.cpp #include "sys.h" #include <stdio.h> #include <stdlib.h> #include <memory.h> int numPro = 0; int numSrc = 0; void struInit(int *availiable,int **max,int **allocation); int main() { int i,*availiable,**max,**allocation; printf("请输入进程数量："); scanf("%d",&numPro); printf("请输入资源数量："); scanf("%d",&numSrc); availiable = (int*)malloc(sizeof(int)*numSrc); max = (int**)malloc(sizeof(int*)*numPro); allocation = (int**)malloc(sizeof(int)*numPro); init(numSrc,numPro); struInit(availiable,max,allocation); SetVal(availiable,max,allocation); system("cls"); while (1) { int cmdNum = 0; printf("\n\n\n"); printf("*******************************************\n"); printf("* 1:检查当前状态安全性 *\n"); printf("* 2:执行请求 *\n"); printf("* 3:打印当前状态 *\n"); printf("* 4:退出 *\n"); printf("*******************************************\n"); printf("请输入功能选项："); scanf("%d",&cmdNum); switch(cmdNum) { case 1: { if(SafeContest() == SUCCESS) DisplaySafeSeq(); }break; case 2: { int *Request = (int*)malloc(sizeof(int)*numSrc); int proNum = 0; printf("输入请求资源的进程号："); scanf("%d",&proNum); printf("请输入请求序列：\n"); for (i=0;i<numSrc;i++) { scanf("%d",&Request[i]); } if(LegitimacyCheck(proNum,Request) == ERROR) { printf("请求序列不合法\n"); continue; } else { PreAllocation(proNum,Request); if(SafeContest() == ERROR) { ReBack(proNum,Request); } else { RealAllocation(proNum); DisplaySafeSeq(); } } }break; case 3:DisplayState(-1);break; case 4:exit(0);break; default:continue; } } return 0; } void struInit(int *availiable,int **max,int **allocation) { int i,j; for(i=0;i<numPro;i++) { max[i] = (int*)malloc(sizeof(int)*numSrc); memset(max[i],0,sizeof(int)*numSrc); } for(i=0;i<numPro;i++) { allocation[i] = (int*)malloc(sizeof(int)*numSrc); memset(allocation[i],0,sizeof(int)*numSrc); } printf("请输入各种资源的剩余数量\n"); for (i=0;i<numSrc;i++) { scanf("%d",&availiable[i]); } for (i=0;i<numPro;i++) { printf("请输入第%d号进程对各种资源的最大需求量：\n",i); for (j=0;j<numSrc;j++) { scanf("%d",&max[i][j]); } } for (i=0;i<numPro;i++) { printf("请输入第%d号进程各种资源的已分配量：\n",i); for (j=0;j<numSrc;j++) { scanf("%d",&allocation[i][j]); } } }
