#include #include #include #include

#define MAX_LINE_LENGTH 1000000 #define DEBUG 0

/* ------------ Project 2 - Problem 3 - Encryption ------------ This file encrypts a text file serially. Most of the work is done for you. Just find what in the program can be parallelized and how to encrypt a character. Don't forget to log the output time of your modified code! */ // ------------------------------------------------------ //

int main (int argc, char *argv[]) { // Catch console errors // Make sure you include the # of threads and your output time file. if (argc != 4) { printf("USE LIKE THIS: encrypt_serial key input_text.txt num_threads output_text.txt time.csv "); return EXIT_FAILURE; }

// Read in the encryption key char* p1; int key = strtol(argv[1], &p1, 10 );

// Open the input, unencrypted text file FILE* inputFile = fopen(argv[2], "r"); // Get num threads int thread_count = strtol(argv[7], NULL, 10);

// Open the output, encrypted text file FILE* outputFile = fopen(argv[4], "w"); FILE* timeFile = fopen(argv[5], "w");

// Allocate and open a buffer to read in the input fseek(inputFile, 0L, SEEK_END); long lSize = ftell(inputFile); rewind(inputFile); unsigned char* buffer = calloc(1, lSize + 1); if (!buffer) fclose(inputFile), fclose(outputFile), // fclose(timeFile), free(buffer), fputs("Memory alloc for inputFile1 failed! ", stderr), exit(1);

// Read the input into the buffer if(1 != fread(buffer, lSize, 1, inputFile)) fclose(inputFile), fclose(outputFile), // fclose(timeFile), free(buffer), fputs("Failed reading into the input buffer! ", stderr), exit(2);

// Allocate a buffer for the encrypted data unsigned char* encrypted_buffer = calloc(1, lSize+1); if (!encrypted_buffer) fclose(inputFile), fclose(outputFile), // fclose(timeFile), free(encrypted_buffer), free(buffer), fputs("Memory alloc for the encrypted buffer failed! ", stderr), exit(3);

// ----> Begin Encryption

// Print to the output file for (int i = 0; i

// Cleanup fclose(inputFile); fclose(outputFile); fclose(timeFile); free(encrypted_buffer); free(buffer);

return 0; } // End main //

/* --------------------------------------------------------------------------------------------------- Sources used: https://stackoverflow.com/questions/3747086/reading-the-whole-text-file-into-a-char-array-in-c */

Please use omp (pragma and its functions) for the parallelization

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