111.c

经典的银行家算法

#include "malloc.h"
#include "stdio.h" 
#define alloclen sizeof(struct allocation) 
#define maxlen sizeof(struct max) 
#define avalen sizeof(struct available) 
#define needlen sizeof(struct need) 
#define finilen sizeof(struct finish) 
#define pathlen sizeof(struct path) 
struct allocation 
{ 
int value; 
struct allocation *next; 
}; 
struct max 
{ 
int value; 
struct max *next; 
}; 
struct available 
{ 
int value; 
struct available *next; 
}; 
struct need 
{ 
int value; 
struct need *next; 
}; 
struct path 
{ 
int value; 
struct path *next; 
}; 
struct finish 
{ 
int stat; 
struct finish *next; 
}; 
int main() 
{ 
int row,colum,status=0,i,j,t,temp,processtest; 
struct allocation *allochead,*alloc1,*alloc2,*alloctemp; 
struct max *maxhead,*maxium1,*maxium2,*maxtemp; 
struct available *avahead,*available1,*available2,*availabletemp,*workhead,*work1,*work2,*worktemp,*worktemp1; 
struct need *needhead,*need1,*need2,*needtemp; 
struct finish *finihead,*finish1,*finish2,*finishtemp; 
struct path *pathhead,*path1,*path2,*pathtemp; 
char c; 
printf("\nPlease enter the type of sources the system has:\n"); 
scanf("%d",&colum); 
printf("Please enter the number of processes now in the memory:\n"); 
scanf("%d",&row); 
printf("Please enter the allocation array:\n"); 
for(i=0;i<row;i++) 
{ 
printf("The allocation for process p%d:\n",i); 
for (j=0;j<colum;j++) 
{ 
printf("The type %c system resource allocated:\n",'A'+j); 
if(status==0) 
{ 
allochead=alloc1=alloc2=(struct allocation*)malloc(alloclen); 
alloc1->next=alloc2->next=NULL; 
scanf("%d",&allochead->value); 
status++; 
} 
else 
{ 
alloc2=(struct allocation *)malloc(alloclen); 
scanf("%d,%d",&alloc2->value); 
if(status==1) 
{ 
allochead->next=alloc2; 
status++; 
} 
alloc1->next=alloc2; 
alloc1=alloc2; 
} 
} 
} 
alloc2->next=NULL; 
status=0; 
printf("Please enter the max array:\n"); 
for(i=0;i<row;i++) 
{ 
printf("The max needed from process p%d:\n",i); 
for (j=0;j<colum;j++) 
{ 
printf("The type %c maxium system resource may needed:\n",'A'+j); 
if(status==0) 
{ 
maxhead=maxium1=maxium2=(struct max*)malloc(maxlen); 
maxium1->next=maxium2->next=NULL; 
scanf("%d",&maxium1->value); 
status++; 
} 
else 
{ 
maxium2=(struct max *)malloc(maxlen); 
scanf("%d,%d",&maxium2->value); 
if(status==1) 
{ 
maxhead->next=maxium2; 
status++; 
} 
maxium1->next=maxium2; 
maxium1=maxium2; 
} 
} 
} 
maxium2->next=NULL; 
status=0; 
printf("Please enter the available array now exists in the system:\n"); 
for (j=0;j<colum;j++) 
{ 
printf("The type %c available system resource number:\n",'A'+j); 
if(status==0) 
{ 
avahead=available1=available2=(struct available*)malloc(avalen); 
workhead=work1=work2=(struct available*)malloc(avalen); 
available1->next=available2->next=NULL; 
work1->next=work2->next=NULL; 
scanf("%d",&available1->value); 
work1->value=available1->value; 
status++; 
} 
else 
{ 
available2=(struct available*)malloc(avalen); 
work2=(struct available*)malloc(avalen); 
scanf("%d,%d",&available2->value); 
work2->value=available2->value; 
if(status==1) 
{ 
avahead->next=available2; 
workhead->next=work2; 
status++; 
} 
available1->next=available2; 
available1=available2; 
work1->next=work2; 
work1=work2; 
} 
} 
available2->next=NULL; 
work2->next=NULL; 
status=0; 
alloctemp=allochead; 
maxtemp=maxhead; 
for(i=0;i<row;i++) 
for (j=0;j<colum;j++) 
{ 
if(status==0) 
{ 
needhead=need1=need2=(struct need*)malloc(needlen); 
need1->next=need2->next=NULL; 
need1->value=maxtemp->value-alloctemp->value; 
status++; 
} 
else 
{ 
need2=(struct need *)malloc(needlen); 
need2->value=(maxtemp->value)-(alloctemp->value); 
if(status==1) 
{ 
needhead->next=need2; 
status++; 
} 
need1->next=need2; 
need1=need2; 
} 
maxtemp=maxtemp->next; 
alloctemp=alloctemp->next; 
} 
need2->next=NULL; 
status=0; 
for(i=0;i<row;i++) 
{ 
if(status==0) 
{ 
finihead=finish1=finish2=(struct finish*)malloc(finilen); 
finish1->next=finish2->next=NULL; 
finish1->stat=0; 
status++; 
} 
else 
{ 
finish2=(struct finish*)malloc(finilen); 
finish2->stat=0; 
if(status==1) 
{ 
finihead->next=finish2; 
status++; 
} 
finish1->next=finish2; 
finish1=finish2; 
} 
} 
finish2->next=NULL; /*Initialization compleated*/ 
status=0; 
processtest=0; 
for(temp=0;temp<row;temp++) 
{ 
alloctemp=allochead; 
needtemp=needhead; 
finishtemp=finihead; 
worktemp=workhead; 
for(i=0;i<row;i++) 
{ 
worktemp1=worktemp; 
if(finishtemp->stat==0) 
{ 
for(j=0;j<colum;j++,needtemp=needtemp->next,worktemp=worktemp->next) 
if(needtemp->value<=worktemp->value) 
processtest++; 
if(processtest==colum) 
{ 
for(j=0;j<colum;j++) 
{ 
worktemp1->value+=alloctemp->value; 
worktemp1=worktemp1->next; 
alloctemp=alloctemp->next; 
} 
if(status==0) 
{ 
pathhead=path1=path2=(struct path*)malloc(pathlen); 
path1->next=path2->next=NULL; 
path1->value=i; 
status++; 
} 
else 
{ 
path2=(struct path*)malloc(pathlen); 
path2->value=i; 
if(status==1) 
{ 
pathhead->next=path2; 
status++; 
} 
path1->next=path2; 
path1=path2; 
} 
finishtemp->stat=1; 
} 
else 
{ 
for(t=0;t<colum;t++) 
alloctemp=alloctemp->next; 
finishtemp->stat=0; 
} 
} 
else 
for(t=0;t<colum;t++) 
{ 
needtemp=needtemp->next; 
alloctemp=alloctemp->next; 
} 
processtest=0; 
worktemp=workhead; 
finishtemp=finishtemp->next; 
} 
} 
path2->next=NULL; 
finishtemp=finihead; 
for(temp=0;temp<row;temp++) 
{ 
if(finishtemp->value==0) 
{ 
printf("\nWARNING,the system is in nonsafe status!\n"); 
exit(0); 
} 
finishtemp=finishtemp->next; 
} 
printf("\nThe system is in safe status!\n"); 
printf("\nThe safe sequence is: \n"); 
do 
{ 
printf("p%d ",pathhead->value); 
} 
while(pathhead=pathhead->next); 
}