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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// char *get_line()
// 400720: 53 push %rbx
// 400721: 48 83 ec 10 sub $0x10,%rsp
// 400725: 48 89 e7 mov %rsp,%rdi
// 400728 e8 73 ff ff ff callq 4006a0 <gets>
char *get_line() {
char buf[4];
char *result;
gets(buf);
result = malloc(strlen(buf));
strcpy(result, buf);
return result;
}
int main(void) {
printf("%s\n", get_line());
}
// A. B. (I mistakingly thought $0x10 was the same as $10...)
// 00 34 33 32 31 30 39 38 return address
// 37 36 35 34 33 32 31 30 callee saved %rbx
// 39 38 37 36 35 34 33 32< sub $rsp - 8
// 31 30 00 00 00 00 00 40 sub $rsp -16
// 07 32< return address gets
//
// C. 00 34 33 32 31 30 39 38
// D. %rbx
// E. Malloc should consider the terminating null (strlen+1) and check for NULL pointer result
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