add related info about deadlock and ipc: pipe, signal
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yuchen
parent
e378ef4376
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026015ed25
243
related_info/lab7/deadlock/bankers-homework.py
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243
related_info/lab7/deadlock/bankers-homework.py
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import os
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import random
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import numpy as np
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import itertools
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class Bankers(object):
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def __init__(self, totalResource):
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#initiating
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self.RESOURCE = totalResource
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def SignProcesses(self, max_, allocated_):
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self.max = max_
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self.allocated = allocated_
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self.need = self.CalcNeed()
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self.avaliable = self.CalcAvaliable()
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self.finished = [False]*len(self.allocated)
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def Difference(self,a,b):
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#return matrix subtracted from a by b
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res = []
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for i in range(len(a)):
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tmp = []
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for j in range(len(a[i])):
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tmp.append(a[i][j]-b[i][j])
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res.append(tmp)
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return res
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def CalcNeed(self):
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#calc request by subtracting signed matrix from max matrix
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return self.Difference(self.max,self.allocated)
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def CalcAvaliable(self):
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"""Calc Avaliable Resource"""
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a = self.allocated
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res = []
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for j in range(len(a[0])):
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tmp = 0
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for i in range(len(a)):
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tmp += a[i][j]
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res.append(self.RESOURCE[j] - tmp)
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return res
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def ExecuteProcess(self,index):
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#check if less avaliable than Request
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# YOUR CODE, YOUR ID
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#check END here
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#allocating what they need.
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# YOUR CODE, YOUR ID
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#allocating END here
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pass
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def TempSafeCheckAfterRelease(self):
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#check if at least one request can be done after previous process done. not check whole sequances.
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#if every element of Requests can't accepted after previous process done, this mean it is not safe state
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# YOUR CODE, YOU ID
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#check END here
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pass
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def print_matrixes(self):
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print "_____________________________________________"
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print "MAX\t\tAllocated\tNeed"
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for idx in range(len(self.max)):
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print "%s\t%s\t%s" % (self.max[idx],self.allocated[idx], self.need[idx])
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print "_____________________________________________"
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print "Resources:"
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print "Total: %s\tAvailable: %s\n" % (self.RESOURCE, self.avaliable)
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def ReleasingProcess(self,index):
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for i in range(0,len(self.RESOURCE)):
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self.finished[index] = True
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self.allocated[index][i] = 0
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self.avaliable = self.CalcAvaliable()
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def Execute(self):
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i = 0
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# get all permutation of processes
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perm = itertools.permutations(range(procnum), procnum)
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permArray = np.asarray(list(perm))
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for arr in permArray:
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for i in arr:
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if self.finished[i] == False:
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print "Executing..."
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print "Request: "
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print self.need[i]
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#check if less avaliable than Request
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if self.ExecuteProcess(i):
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print "Dispatching Done..."
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self.print_matrixes()
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print "-----Releasing Process------"
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self.ReleasingProcess(i)
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self.print_matrixes()
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#check if at least one request can be done after previous process done. not check whole sequances.
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#if every element of Requests can't accepted after previous process done, this mean it is not safe state
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if not (self.TempSafeCheckAfterRelease()):
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print "SAFE STATE: NOT SAFE - There are no sequances can avoid Deadlock"
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return False
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processes.append(i)
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else:
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print "HOLD: not enough Resource"
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if i == len(self.allocated)-1:
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i = 0
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else:
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i += 1
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check = True
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for k in range(0,len(self.allocated)):
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if self.finished[k] == False:
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check = False
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break
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if check == True:
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return True
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break
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#every permutation of processes is false
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return False
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def getmax():
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res = []
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for j in range(procnum):
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tmp = []
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for i in range(len(total_resources)):
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randnum=random.random()
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remain_max=0
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if j >0:
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remain_max=total_resources[i]
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for k in range(j):
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remain_max=remain_max-res[k][i]
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if remain_max < 0:
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remain_max=0
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else:
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remain_max=total_resources[i]
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tmp.append((int)(randnum*remain_max*0.8))
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res.append(tmp)
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return res
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def getallocated():
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res = []
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for j in range(procnum):
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tmp = []
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for i in range(len(total_resources)):
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randnum=random.random()
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remain=0
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if j >0:
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remain=max[j][i]
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for k in range(j):
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remain=remain-res[k][i]
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if remain < 0:
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remain=0
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else:
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remain=max[j][i]
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tmp.append((int)(randnum*remain))
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res.append(tmp)
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return res
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print "start here"
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# random seed
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seed = 2
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random.seed(seed)
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# the number of process list
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procnum = 3
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# the number of type of resource
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resnum = 4
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# the max total value of resource
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restotalval = 30
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# the total resources list
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total_resources=[]
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# the total processes
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processes=[]
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# set the real total value of resource in total_resources
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for i in range(resnum):
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total_resources.append((int)(restotalval*random.random()))
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# init the Banker
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b = Bankers(total_resources)
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# get the max request values of resources from process
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max=getmax()
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# get the already gotted values of resources from process
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allocated=getallocated()
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# init need matrix, available vector
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b.SignProcesses(max, allocated)
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# print all theses matrixes
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b.print_matrixes()
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# executing Banker algorithm
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result=b.Execute()
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# show results
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if result:
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print "SUCCESS proc lists ",processes
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else:
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print "Failed"
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# total_resources = [6, 5, 7, 6]
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# processes=[]
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# b = Bankers(total_resources)
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#
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# max = [
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# [3, 3, 2, 2],
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# [1, 2, 3, 4],
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# [1, 3, 5, 0],
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# ]
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# allocated = [
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# [1, 2, 2, 1],
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# [1, 0, 3, 3],
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# [1, 2, 1, 0],
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# ]
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#
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# b.SignProcesses(max, allocated)
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# b.print_matrixes()
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# result=b.Execute()
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# if result:
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# print "SUCCESS proc lists ",processes
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# else:
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# print "Failed"
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#
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#
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# total_resources = [10, 10, 8, 5]
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# processes=[]
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# b = Bankers(total_resources)
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# max = [
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# [10, 8, 2,5],
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# [6, 1, 3,1],
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# [3, 1, 4,2],
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# [5, 4, 2,1]
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# ]
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# allocated = [
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# [3, 0, 0,3],
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# [1, 1, 2,0],
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# [2, 1, 2,1],
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# [0, 0, 2,0]
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# ]
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# b.SignProcesses(max, allocated)
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# b.print_matrixes()
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# result=b.Execute()
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# if result:
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# print "SUCCESS proc lists ",processes
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# else:
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# print "Failed"
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257
related_info/lab7/deadlock/example-output.txt
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257
related_info/lab7/deadlock/example-output.txt
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@ -0,0 +1,257 @@
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start here
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [17, 8, 0, 0] [1, 8, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [4, 5, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [2, 2, 0, 1]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [11, 20, 1, 2]
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Executing...
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Request:
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[1, 8, 0, 0]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [18, 16, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [4, 5, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [2, 2, 0, 1]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [10, 12, 1, 2]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [4, 5, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [2, 2, 0, 1]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [28, 28, 1, 2]
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Executing...
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Request:
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[4, 5, 0, 0]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [4, 5, 0, 0] [0, 0, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [2, 2, 0, 1]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [24, 23, 1, 2]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [2, 2, 0, 1]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [28, 28, 1, 2]
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Executing...
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Request:
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[2, 2, 0, 1]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[2, 2, 0, 1] [2, 2, 0, 1] [0, 0, 0, 0]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [26, 26, 1, 1]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[18, 16, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[4, 5, 0, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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[2, 2, 0, 1] [0, 0, 0, 0] [0, 0, 0, 0]
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_____________________________________________
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Resources:
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Total: [28, 28, 1, 2] Available: [28, 28, 1, 2]
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SUCCESS proc lists [0, 1, 2]
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [1, 2, 2, 1] [2, 1, 0, 1]
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[1, 2, 3, 4] [1, 0, 3, 3] [0, 2, 0, 1]
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[1, 3, 5, 0] [1, 2, 1, 0] [0, 1, 4, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [3, 1, 1, 2]
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Executing...
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Request:
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[2, 1, 0, 1]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [3, 3, 2, 2] [0, 0, 0, 0]
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[1, 2, 3, 4] [1, 0, 3, 3] [0, 2, 0, 1]
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[1, 3, 5, 0] [1, 2, 1, 0] [0, 1, 4, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [1, 0, 1, 1]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 2, 3, 4] [1, 0, 3, 3] [0, 2, 0, 1]
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[1, 3, 5, 0] [1, 2, 1, 0] [0, 1, 4, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [4, 3, 3, 3]
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Executing...
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Request:
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[0, 2, 0, 1]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 2, 3, 4] [1, 2, 3, 4] [0, 0, 0, 0]
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[1, 3, 5, 0] [1, 2, 1, 0] [0, 1, 4, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [4, 1, 3, 2]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 2, 3, 4] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 3, 5, 0] [1, 2, 1, 0] [0, 1, 4, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [5, 3, 6, 6]
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Executing...
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Request:
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[0, 1, 4, 0]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 2, 3, 4] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 3, 5, 0] [1, 3, 5, 0] [0, 0, 0, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [5, 2, 2, 6]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[3, 3, 2, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 2, 3, 4] [0, 0, 0, 0] [0, 0, 0, 0]
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[1, 3, 5, 0] [0, 0, 0, 0] [0, 0, 0, 0]
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_____________________________________________
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Resources:
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Total: [6, 5, 7, 6] Available: [6, 5, 7, 6]
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SUCCESS proc lists [0, 1, 2]
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_____________________________________________
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MAX Allocated Need
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[10, 8, 2, 5] [3, 0, 0, 3] [7, 8, 2, 2]
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[6, 1, 3, 1] [1, 1, 2, 0] [5, 0, 1, 1]
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[3, 1, 4, 2] [2, 1, 2, 1] [1, 0, 2, 1]
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[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
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_____________________________________________
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Resources:
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Total: [10, 10, 8, 5] Available: [4, 8, 2, 1]
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Executing...
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Request:
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[7, 8, 2, 2]
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HOLD: not enough Resource
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Executing...
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Request:
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[5, 0, 1, 1]
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HOLD: not enough Resource
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Executing...
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Request:
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[1, 0, 2, 1]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[10, 8, 2, 5] [3, 0, 0, 3] [7, 8, 2, 2]
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[6, 1, 3, 1] [1, 1, 2, 0] [5, 0, 1, 1]
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[3, 1, 4, 2] [3, 1, 4, 2] [0, 0, 0, 0]
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[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
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_____________________________________________
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Resources:
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Total: [10, 10, 8, 5] Available: [3, 8, 0, 0]
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-----Releasing Process------
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_____________________________________________
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MAX Allocated Need
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[10, 8, 2, 5] [3, 0, 0, 3] [7, 8, 2, 2]
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[6, 1, 3, 1] [1, 1, 2, 0] [5, 0, 1, 1]
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[3, 1, 4, 2] [0, 0, 0, 0] [0, 0, 0, 0]
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[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
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_____________________________________________
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Resources:
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Total: [10, 10, 8, 5] Available: [6, 9, 4, 2]
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Executing...
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Request:
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[7, 8, 2, 2]
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HOLD: not enough Resource
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Executing...
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Request:
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[5, 0, 1, 1]
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Dispatching Done...
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_____________________________________________
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MAX Allocated Need
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[10, 8, 2, 5] [3, 0, 0, 3] [7, 8, 2, 2]
|
||||
[6, 1, 3, 1] [6, 1, 3, 1] [0, 0, 0, 0]
|
||||
[3, 1, 4, 2] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
|
||||
_____________________________________________
|
||||
Resources:
|
||||
Total: [10, 10, 8, 5] Available: [1, 9, 3, 1]
|
||||
|
||||
-----Releasing Process------
|
||||
_____________________________________________
|
||||
MAX Allocated Need
|
||||
[10, 8, 2, 5] [3, 0, 0, 3] [7, 8, 2, 2]
|
||||
[6, 1, 3, 1] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[3, 1, 4, 2] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
|
||||
_____________________________________________
|
||||
Resources:
|
||||
Total: [10, 10, 8, 5] Available: [7, 10, 6, 2]
|
||||
|
||||
Executing...
|
||||
Request:
|
||||
[7, 8, 2, 2]
|
||||
Dispatching Done...
|
||||
_____________________________________________
|
||||
MAX Allocated Need
|
||||
[10, 8, 2, 5] [10, 8, 2, 5] [0, 0, 0, 0]
|
||||
[6, 1, 3, 1] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[3, 1, 4, 2] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
|
||||
_____________________________________________
|
||||
Resources:
|
||||
Total: [10, 10, 8, 5] Available: [0, 2, 4, 0]
|
||||
|
||||
-----Releasing Process------
|
||||
_____________________________________________
|
||||
MAX Allocated Need
|
||||
[10, 8, 2, 5] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[6, 1, 3, 1] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[3, 1, 4, 2] [0, 0, 0, 0] [0, 0, 0, 0]
|
||||
[5, 4, 2, 1] [0, 0, 2, 0] [5, 4, 0, 1]
|
||||
_____________________________________________
|
||||
Resources:
|
||||
Total: [10, 10, 8, 5] Available: [10, 10, 6, 5]
|
||||
|
||||
Failed
|
||||
23
related_info/lab7/ipc/pipe-ex1.py
Normal file
23
related_info/lab7/ipc/pipe-ex1.py
Normal file
@ -0,0 +1,23 @@
|
||||
#!/usr/bin/env python
|
||||
# -*- encoding: utf8 -*-
|
||||
import os, sys
|
||||
print "I'm going to fork now - the child will write something to a pipe, and the parent will read it back"
|
||||
r, w = os.pipe() # r,w是文件描述符, 不是文件对象
|
||||
pid = os.fork()
|
||||
if pid:
|
||||
# 父进程
|
||||
os.close(w) # 关闭一个文件描述符
|
||||
r = os.fdopen(r) # 将r转化为文件对象
|
||||
print "parent: reading"
|
||||
txt = r.read()
|
||||
os.waitpid(pid, 0) # 确保子进程被撤销
|
||||
else:
|
||||
# 子进程
|
||||
os.close(r)
|
||||
w = os.fdopen(w, 'w')
|
||||
print "child: writing"
|
||||
w.write("here's some text from the child")
|
||||
w.close()
|
||||
print "child: closing"
|
||||
sys.exit(0)
|
||||
print "parent: got it; text =", txt
|
||||
43
related_info/lab7/ipc/pipe-ex2.c
Normal file
43
related_info/lab7/ipc/pipe-ex2.c
Normal file
@ -0,0 +1,43 @@
|
||||
/*
|
||||
* From
|
||||
* [url]http://www.crasseux.com/books/ctutorial/Programming-with-pipes.html[/url]
|
||||
* but changed to use fgets() instead of the GNU extension getdelim()
|
||||
*/
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
int main()
|
||||
{
|
||||
FILE *ps_pipe;
|
||||
FILE *grep_pipe;
|
||||
int bytes_read;
|
||||
char buffer[100]; /* could be anything you want */
|
||||
/* Open our two pipes
|
||||
ls -a | grep pipe*
|
||||
*/
|
||||
|
||||
ps_pipe = popen("/bin/ls -a", "r");
|
||||
grep_pipe = popen("/bin/grep 'pipe*'", "w");
|
||||
/* Check that pipes are non-null, therefore open */
|
||||
if ((!ps_pipe) || (!grep_pipe)) {
|
||||
fprintf(stderr, "One or both pipes failed.\n");
|
||||
return EXIT_FAILURE;
|
||||
}
|
||||
bytes_read = 0;
|
||||
while (fgets(buffer, sizeof(buffer), ps_pipe)) {
|
||||
fprintf(grep_pipe, "%s", buffer);
|
||||
bytes_read += strlen(buffer);
|
||||
}
|
||||
printf("Total bytes read = %d\n", bytes_read);
|
||||
/* Close ps_pipe, checking for errors */
|
||||
if (pclose(ps_pipe) != 0) {
|
||||
fprintf(stderr, "Could not run 'ls', or other error.\n");
|
||||
}
|
||||
/* Close grep_pipe, cehcking for errors */
|
||||
if (pclose(grep_pipe) != 0) {
|
||||
fprintf(stderr, "Could not run 'grep', or other error.\n");
|
||||
}
|
||||
/* Exit! */
|
||||
return 0;
|
||||
}
|
||||
|
||||
28
related_info/lab7/ipc/signal-ex1.c
Normal file
28
related_info/lab7/ipc/signal-ex1.c
Normal file
@ -0,0 +1,28 @@
|
||||
#include <unistd.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <signal.h>
|
||||
|
||||
// Define the function to be called when ctrl-c (SIGINT) signal is sent to process
|
||||
void
|
||||
signal_callback_handler(int signum)
|
||||
{
|
||||
printf("Caught signal %d\n",signum);
|
||||
// Cleanup and close up stuff here
|
||||
|
||||
// Terminate program
|
||||
exit(signum);
|
||||
}
|
||||
|
||||
int main()
|
||||
{
|
||||
// Register signal and signal handler
|
||||
signal(SIGINT, signal_callback_handler);
|
||||
|
||||
while(1)
|
||||
{
|
||||
printf("Program processing stuff here.\n");
|
||||
sleep(1);
|
||||
}
|
||||
return EXIT_SUCCESS;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user