Adding lab13 dir

lab-13/main1.cpp

+/*
+ * main1.cpp for CPTR 245 Lab 13 on libraries and versions
+ */
+
+#include <fstream>    // std::ifstream
+#include <iomanip>    // std::setfill, std::setw
+#include <iostream>   // std::cout, std::endl
+#include <sys/stat.h> // stat() to get file size
+
+#include <openssl/crypto.h>
+#include <openssl/md5.h>
+
+int main(int argc, char *argv[]) {
+  // verify proper command-line arguments
+  if (argc != 2) {
+    std::cerr << "USAGE: ./a.out FILEPATH" << std::endl;
+    exit(1);
+  }
+
+  // print version found in header file
+  std::cout << "SSL Header Version:  " << OPENSSL_VERSION_TEXT << std::endl;
+  // print version found in library linked at runtime
+  std::cout << "SSL Library Version: " << OpenSSL_version(OPENSSL_VERSION)
+            << std::endl;
+
+  // get file size
+  struct stat statbuf;
+  if (stat(argv[1], &statbuf) < 0) {
+    std::cerr << "Unable to get info on the file" << std::endl;
+    exit(1);
+  }
+  int fileSize = statbuf.st_size;
+
+  // open and read file into new buffer
+  char *buffer = new char[fileSize];
+  std::ifstream inFS(argv[1]);
+  if (!inFS.is_open()) {
+    std::cerr << "Could not open file " << argv[1] << '.' << std::endl;
+    return 1;
+  }
+  inFS.read(buffer, fileSize);
+  inFS.close();
+
+  // calculate MD5
+  unsigned char result[MD5_DIGEST_LENGTH];
+  MD5((unsigned char *)buffer, fileSize, result);
+
+  // print MD5 in hex digits
+  for (int i = 0; i < MD5_DIGEST_LENGTH; i++) {
+    std::cout << std::setw(2) << std::setfill('0') << std::hex
+              << (int)result[i];
+  }
+  std::cout << std::dec << "  " << argv[1] << '(' << fileSize << ')'
+            << std::endl;
+
+  // free allocated memory and return
+  delete[] buffer;
+  return 0;
+}
+