我正在编写一个程序,从文件中读取任意数量的行(其中第一行是我不需要的头),并为它们动态分配内存。
char buffer[350];
char** addresses;
char** temp;
int i = 0;
int check = 10;
addresses = malloc(sizeof(char*) * check); /* let's start with 10 potential addresses */
if(addresses == NULL){
printf("Unable to allocate memory.n");
exit(1);}
fgets(buffer, sizeof(buffer), stdin); /* call this once to get past the header line */
while(fgets(buffer, sizeof(buffer), stdin) != NULL)
{
if(i > check) /* we need more memory */
{
temp = realloc(addresses,(2*check)*sizeof(char*)); /* double the memory we have */
if(temp == NULL)
{
printf("Unable to re-allocate memory");
exit(1);
}
else
{
addresses = temp;
check *= 2;
printf("reallocating to %dn", check);
}
}
addresses[i] = malloc(strlen(buffer)); /* get memory for number of chars in each line */
printf("2 %dn", i);
strcpy(addresses[i],buffer);
i++;
}
当我运行它时,我得到一个内存损坏错误:
reallocating to 20
reallocating to 40
reallocating to 80
reallocating to 160
reallocating to 320
reallocating to 640
*** glibc detected *** ./a.out: malloc(): memory corruption: 0x0000000007721310 ***
======= Backtrace: =========
/lib64/libc.so.6[0x37f0a71fbe]
/lib64/libc.so.6(__libc_malloc+0x6e)[0x37f0a73dfe]
./a.out[0x400789]
/lib64/libc.so.6(__libc_start_main+0xf4)[0x37f0a1d9f4]
./a.out[0x4005d9]
是什么原因造成的?
addresses[i] = malloc(strlen(buffer)); /* get memory for number of chars in each line */
printf("2 %dn", i);
strcpy(addresses[i],buffer);
您没有为终止NUL字符分配空间。