learning experience

password_gen.c

@@ -0,0 +1,59 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <string.h>
+
+int str_to_int(char* str) {
+  int output = 0;
+
+  for (int i = 0; i < strlen(str); i++) {
+    output *= 10;
+    output += str[i] - '0';
+  }
+
+  return output;
+}
+
+void invalid_args(int argc) {
+  if (argc < 4 && argc > 5) {
+    printf("nuhuh\n");
+    exit(1);
+  }
+}
+
+int random_len(int min_length, int max_length) {
+  return rand() % (max_length - min_length + 1) + min_length;
+}
+
+char* random_str(int length, char* symbols) {
+  char* str = malloc(sizeof(char) * (length + 1));
+
+  for (int i = 0; i < length; i++) {
+    int index = rand() % strlen(symbols);
+    str[i] = symbols[index];
+  }
+
+  str[length] = '\0';
+
+  return str;
+}
+
+int main(int argc, char** argv) {
+  invalid_args(argc);
+  srand(time(NULL));
+
+  int min_length = str_to_int(argv[1]);
+  int max_length = str_to_int(argv[2]);
+
+  int length = random_len(min_length, max_length);
+
+  if (argc != 4) {
+    char* password = random_str(length, argv[4]);
+    puts(password);
+    free(password);
+  } else {
+    char* password = random_str(length, argv[3]);
+    puts(password);
+    free(password);
+  }
+}