filename2 = (char *)malloc(sizeof(strlen(filename1) + strlen(prefix)+1));
enc()
和dec()
,它会引发错误,但是会创建新的加密文件。如果先调用enc()
,然后再使用加密文件,则如果在dec()
中使用,则显示
错误:munmap_chunk():无效指针] >>如果调用了 错误:free():下一个大小无效(正常)>] >>enc()
并终止了程序,然后运行它并在现在加密的文件上使用dec()
,它会显示void enc()
{
FILE *fp1, *fp2;
char filename1[FILENAME_MAX];
int i;
int size;
int shift;
printf("Enter filename:");
scanf(" %[^\n]s",filename1);
while((fp1 = fopen(filename1, "r")) == NULL){
fprintf(stderr, "Error: Unable to open file %s\nTry Again\n", filename1);
printf("Enter filename:");
scanf(" %[^\n]s",filename1);
}
printf("Enter shift:");
scanf("%d",&shift);
const char *prefix = "encrypted_";
char *filename2;
filename2 = (char *)malloc(sizeof(strlen(filename1) + strlen(prefix)+1));
strcpy(filename2, prefix);
strcat(filename2, filename1);
if ((fp2 = fopen(filename2, "w")) == NULL) {
fprintf(stderr, "Error: Unable to open file %s\n", filename1);
exit(EXIT_FAILURE);
}
free(filename2);
int ch;
while ((ch = getc(fp1)) != EOF) {
if (ch >= 'A' && ch <= 'Z') {
putc(((ch - 'A') + shift) % 26 + 'A', fp2);
}
else if (ch >= 'a' && ch <= 'z') {
putc(((ch - 'a') + shift) % 26 + 'a', fp2);
}
else {
putc(ch, fp2);
}
}
fclose(fp1);
fclose(fp2);
}
void dec()
{
FILE *fp1, *fp2;
char filename1[FILENAME_MAX];
int i;
int size;
int shift;
printf("Enter filename:");
scanf(" %[^\n]s",filename1);
while((fp1 = fopen(filename1, "r")) == NULL){
fprintf(stderr, "Error: Unable to open file %s\nTry Again\n", filename1);
printf("Enter filename:");
scanf(" %[^\n]s",filename1);
}
printf("Enter shift:");
scanf("%d",&shift);
shift = 26-(shift%26);
const char *prefix = "decrypted_";
char *filename2;
filename2 = (char *)malloc(sizeof(strlen(filename1) + strlen(prefix)+1));
strcpy(filename2, prefix);
strcat(filename2, filename1);
if ((fp2 = fopen(filename2, "w")) == NULL) {
fprintf(stderr, "Error: Unable to open file %s\n", filename1);
exit(EXIT_FAILURE);
}
free(filename2);
int ch;
while ((ch = getc(fp1)) != EOF) {
if (ch >= 'A' && ch <= 'Z') {
putc(((ch - 'A') + shift) % 26 + 'A', fp2);
}
else if (ch >= 'a' && ch <= 'z') {
putc(((ch - 'a') + shift) % 26 + 'a', fp2);
}
else {
putc(ch, fp2);
}
}
fclose(fp1);
fclose(fp2);
}
反复调用函数enc()和dec(),它会引发错误,但会创建新的加密文件。如果先调用enc(),然后再使用加密文件,则如果在dec()中使用,则显示错误:...
filename2 = (char *)malloc(sizeof(strlen(filename1) + strlen(prefix)+1));
您正在为sizeof(size_t)
保留空间,并且可能会调用malloc(8)
,请删除sizeof
关键字:
filename2 = malloc(strlen(filename1) + strlen(prefix)+1);
filename2 = (char *)malloc(sizeof(strlen(filename1) + strlen(prefix)+1));