我正在写一个加密单词的程序,问题是,程序运行正常,但是当我输入2/3而不是4个arg时,我会得到核心转储:
这是我的代码:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <crypt.h>
#include <time.h>
int DisplayHelp(){
printf("Usage :./task1 <wordlist> <min> <max>\n");
printf("\t<wordlist> : A file path/name in which contains the password dictionary \n");
printf("\t<min> : An integer value greater than 1.\n");
printf("\t\tThis value represents the minimum length of the password\n");
printf("\t<max> : An integer value greater than or equal to <min>.\n");
printf("\t\t<max> represents the maximum length of the password.\n");
exit(1);
}
int main(int argc, char * argv[] ){
char * type1="$1$";
char * type6="$6$";
char * salt="$";
char * mdresult;
char encyption_scheme[20];
FILE * fp;
FILE * fp1;
char input1 [50];
int length;
int line=0;
int line2=0;
int Min=atoi(argv[2]);
int Max=atoi(argv[3]);
if(Min>Max || argc!=4){
DisplayHelp();
}
fp = fopen(argv[1],"r"); //Reading of file
if(fp == NULL){
printf("Fatal error! %s file not found\n",argv[1]);
printf("Program halted. Please verify the file path and try again.\n");
exit(1);
}
fclose(fp);
time_t current_time = time(NULL);
struct tm *tm = localtime(¤t_time);
printf("Program Started At %s\n", asctime(tm));
fp=fopen(argv[1],"r");
while(fgets(input1,50,fp)){
//line++; //Line +1
length=strlen(input1)-1;
input1[strlen(input1)-1]='\0';
if(length >= Min && length <= Max){
line++;
strcpy(encyption_scheme,type1);
strcat(encyption_scheme,salt);
mdresult = crypt(input1,encyption_scheme);
line2++;
strcpy(encyption_scheme,type6);
strcat(encyption_scheme,salt);
sharesult = crypt(input1,encyption_scheme);
line2++;
fp1=fopen("Filename.txt","a");
if (fp1==NULL)
exit(-1);
fprintf(fp1, "%s:%s\n", input1, mdresult);
fprintf(fp1, "%s:%s\n", input1, sharesult);
fclose(fp1);
}
}
printf("Total number of words processed => %d\n", line);
printf("Total number of generated entries => %d\n", line2);
fclose(fp);
current_time = time(NULL);
tm = localtime(¤t_time);
printf("\n");
printf("Program Ended At %s\n", asctime(tm)); //Add time
}
1条答案
按热度按时间2wnc66cl1#
您在检查
argv[2]
和argv[3]
是否存在之前使用了它们。更改:变成了这样:
因此在验证
argv
的元素存在之前,您不会访问它们。