Complete the following program in order you work with files mapped in memory.Pro
ID: 3820134 • Letter: C
Question
Complete the following program in order you work with files mapped in memory.Program will map a binary file (people.bin) that has struct Person records (used in program 4) for listing thefile and searching persons in the file.The mapping will be stored in a struct Memory variable the that keeps the pointer to memory and the size of thememory block.Functionality:
void print(const struct Person &p): It will print the person p.
(Implemented)
void mapFile(struct Memory &memo): It will map the file "people.bin" inmemory and it will return the mapping in the by reference parameter memo (ptrand size).
void unmapFile(struct Memory &memo): It will unmap the file from memory.
void list(const struct Memory &memo) : It will print all the people in themapped file that it is in the memo parameter.
bool lookFor(string name, const struct Memory &memo, struct Person &p): Itwill search for a person named name in the mapped file that it is in the memo parameter. If found it will return true and the by reference parameter p will befilled with all the information of the person. If not found it will return false.
/* * File: Program9.cpp * Author: *
* Created on April XX, 2017, hh:mm AM/PM */
#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
struct Person {
char name[80];
int age;
char sex; /* M = Male and F = Female */
char lookingFor; /* M = Male and F = Female */
char hobby[80];
};
struct Memory {
void *ptr;
int size;
};
void print(const struct Person &p);
void mapFile(struct Memory &memo);
void unmapFile(struct Memory &memo);
void list(const struct Memory &memo);
bool lookFor(string name, const struct Memory &memo, struct Person &p);
int main(int argc, char** argv) {
struct Memory memo;
struct Person p;
mapFile(memo);
list(memo);
cout << "Looking for Jane ... " << endl;
if (lookFor("Jane",memo, p)) print(p);
else cout << "Jane NOT found" << endl;
cout << endl << "Looking for James ... " << endl;
if (lookFor("James",memo, p)) print(p);
else cout << "James NOT found" << endl;
unmapFile(memo);
return 0;}
void print(const struct Person &p) {
cout << "Name: " << p.name << endl;
cout << "Age: " << p.age << endl;
cout << "Sex: " << p.sex << endl;
cout << "Looking For: " << p.lookingFor << endl;
cout << "Hobby: " << p.hobby << endl;
}void mapFile(struct Memory &memo) {
}
void unmapFile(struct Memory &memo) {
}
void list(const struct Memory &memo) {
}
bool lookFor(string name, const struct Memory &memo, struct Person &p){
return false;}
Execution Example:
Name: John
Age: 20
Sex: M
Looking For: F
Hobby: Basketball
Name: Jane
Age: 21
Sex: F
Looking For: M
Hobby: Basketball
Name: Peter
Age: 22
Sex: M
Looking For: F
Hobby: Football
Name: Mary
Age: 20
Sex: F
Looking For: M
Hobby: Art
Name: Bob
Age: 21
Sex: M
Looking For: F
Hobby: Baseball
Name: Bill
Age: 24
Sex: M
Looking For: F
Hobby: baseball
Looking for Jane ...
Name: Jane
Age: 21
Sex: F
Looking For: M
Hobby: Basketball
Looking for James ...
James NOT found
Explanation / Answer
Hi,
Please find the code for the fucntions below:-
/* * File: Program9.cpp * Author: *
* Created on April XX, 2017, hh:mm AM/PM */
#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <cstring>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
struct Person {
char name[80];
int age;
char sex; /* M = Male and F = Female */
char lookingFor; /* M = Male and F = Female */
char hobby[80];
};
struct Memory {
void *ptr;
int size;
};
void print(const struct Person &p);
void mapFile(struct Memory &memo);
void unmapFile(struct Memory &memo);
void list(const struct Memory &memo);
bool lookFor(string name, const struct Memory &memo, struct Person &p);
int main(int argc, char** argv) {
struct Memory memo;
struct Person p;
mapFile(memo);
list(memo);
cout << "Looking for Jane ... " << endl;
if (lookFor("Jane",memo, p)) print(p);
else cout << "Jane NOT found" << endl;
cout << endl << "Looking for James ... " << endl;
if (lookFor("James",memo, p)) print(p);
else cout << "James NOT found" << endl;
unmapFile(memo);
return 0;}
void print(const struct Person &p) {
cout << "Name: " << p.name << endl;
cout << "Age: " << p.age << endl;
cout << "Sex: " << p.sex << endl;
cout << "Looking For: " << p.lookingFor << endl;
cout << "Hobby: " << p.hobby << endl;
}void mapFile(struct Memory &memo)
{
/Create a file_mapping object
std::file_mapping mapping("/people.bin", std::memory_mappable::read_write);
//Create a mapped_region covering the whole file
std::mapped_region region(mapping, std::mapped_region::read_write);
//Obtain the size and the address of the mapped region
*memo.ptr = region.get_address();
std::size_t memo.size = region.get_size();
//Set the whole file
std::memset(memo.ptr, 0xFF, memo.size);
}
void unmapFile(struct Memory &memo)
{
free (memo)
}
void list(const struct Memory &memo)
{
for (int i=0;i<7;i++)
{
/*The list is accessed by the pointer to structure */
cout << "Name: " << memo->name << endl;
cout << "Age: " << memo->age << endl;
cout << "Sex: " << memo->sex << endl;
cout << "Looking For: " << memo->lookingFor << endl;
cout << "Hobby: " << memo->hobby << endl;
memo+1;
}
}
bool lookFor(string name, const struct Memory &memo, struct Person &p)
{
return false;
}
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.