Question

IN MIPS ASSEMBLY

Macro File: Create macros to print an int, print a char, print a string, get a string from the user, open file, close file, read file, and allocate heap memory. You can use more macros than these if you like.

Main Program File:

1. Allocate 1024 bytes of dynamic memory and save the pointer to the area.
2. The main program is a loop in which you ask the user for a filename. If they enter nothing for the filename, exit the program. Otherwise:
   1. Open the file for reading. If the file does not exist, print an error message and terminate the program.
   2. Read the file into an input buffer space of 1024 bytes.
   3. Close the file.
   4. Invoke the print string macro to output the original data to the console.
   5. Call the compression function. Save the size of the compressed data in memory.
   6. Call a function to print the compressed data.
   7. Call the uncompress function, which uncompresses to the console.
   8. Print the number of bytes in the original and compressed data.
3. The compression function implements the RLE algorithm above and stores the compressed data in the heap. Before the function call, set $a0 to the address of the input buffer, set $a1 to the address of the compression buffer, set $a2 to the size of the original file. The function should “return” the size of the compressed data in $v0.
4. The uncompress function will repeat characters as indicated in the compressed file. For example, if the compressed file is ‘A2B3C1’ it will print
5. ‘AABBBC’. Note that this is different from the print string macro which just uses a syscall to print a string.

Answer 1

#include<sys/types.h>
#includ<sys/stat.h>
#include <fcntl.h>  
int open (const char* Path, int flags [, int mode ]);
extern int errno;

int main()

{

int fd = open("foo.txt", O_RDONLY | O_CREAT);

printf("fd = %d/n", fd);

if (fd ==-1)

{

printf("Error Number % d\n", errno);

perror("Program");

}

return 0;

}

int main()

{

int fd1 = open("foo.txt", O_RDONLY);

if (fd1 < 0)

{

perror("c1");

exit(1);

}

printf("opened the fd = % d\n", fd1);

if (close(fd1) < 0)

{

perror("c1");

exit(1);

}

printf("closed the fd.\n");

}