user: 提供的汇编代码用C语言表示会是什么样子:

```asm
<read_flag>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %rbx
  sub    $0x58,%rsp
  mov    %edi,-0x44(%rbp)
  mov    %rsi,-0x50(%rbp)
  mov    %edx,-0x48(%rbp)
  mov    %ecx,-0x54(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x18(%rbp)
  xor    %eax,%eax
  mov    %rsp,%rax
  mov    %rax,%rbx
  mov    -0x48(%rbp),%eax
  cltq
  sub    $0x1,%rax
  mov    %rax,-0x28(%rbp)
  mov    -0x48(%rbp),%eax
  cltq
  mov    %rax,%r10
  mov    $0x0,%r11d
  mov    -0x48(%rbp),%eax
  cltq
  mov    %rax,%r8
  mov    $0x0,%r9d
  mov    -0x48(%rbp),%eax
  cltq
  mov    $0x10,%edx
  sub    $0x1,%rdx
  add    %rdx,%rax
  mov    $0x10,%edi
  mov    $0x0,%edx
  div    %rdi
  imul   $0x10,%rax,%rax
  mov    %rax,%rcx
  and    $0xfffffffffffff000,%rcx
  mov    %rsp,%rdx
  sub    %rcx,%rdx
L73:
  cmp    %rdx,%rsp
  je     L59
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  jmp    L73
L59:
  mov    %rax,%rdx
  and    $0xfff,%edx
  sub    %rdx,%rsp
  mov    %rax,%rdx
  and    $0xfff,%edx
  test   %rdx,%rdx
  je     L77
  and    $0xfff,%eax
  sub    $0x8,%rax
  add    %rsp,%rax
  orq    $0x0,(%rax)
L77:
  mov    %rsp,%rax
  add    $0x0,%rax
  mov    %rax,-0x20(%rbp)
  movl   $0x0,-0x38(%rbp)
  movl   $0x0,-0x34(%rbp)
L67:
  mov    -0x48(%rbp),%eax
  mov    -0x38(%rbp),%edx
  sub    %edx,%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x38(%rbp),%eax
  test   %eax,%eax
  jle    L93
  mov    -0x38(%rbp),%edx
  mov    -0x30(%rbp),%eax
  movslq %eax,%rcx
  mov    -0x20(%rbp),%rax
  add    %rax,%rcx
  mov    -0x20(%rbp),%rax
  mov    %rcx,%rsi
  mov    %rax,%rdi
  call   <memmove@plt>
L93:
  mov    -0x38(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x20(%rbp),%rax
  lea    (%rdx,%rax,1),%rsi
  mov    -0x30(%rbp),%edx
  mov    -0x44(%rbp),%eax
  mov    $0x0,%ecx
  mov    %eax,%edi
  call   <recvn@plt>
  cmp    %eax,-0x30(%rbp)
  jne    L103
  lea    -0x38(%rbp),%rdi
  mov    -0x48(%rbp),%ecx
  mov    -0x50(%rbp),%rdx
  mov    -0x48(%rbp),%esi
  mov    -0x20(%rbp),%rax
  mov    %rdi,%r8
  mov    %rax,%rdi
  call   <search_flag@plt>
  mov    %eax,-0x2c(%rbp)
  cmpl   $0x0,-0x2c(%rbp)
  jne    L90
  mov    $0x0,%eax
  jmp    L56
L90:
  cmpl   $0x0,-0x54(%rbp)
  je     L33
  mov    -0x38(%rbp),%edx
  mov    -0x30(%rbp),%eax
  sub    %edx,%eax
  add    %eax,-0x34(%rbp)
  mov    -0x34(%rbp),%eax
  cmp    -0x54(%rbp),%eax
  jge    L61
  jmp    L67
L33:
  nop
  jmp    L67
L103:
  nop
  jmp    L127
L61:
  nop
L127:
  mov    $0xffffffff,%eax
L56:
  mov    %rbx,%rsp
  mov    -0x18(%rbp),%rdx
  sub    %fs:0x28,%rdx
  je     L14
  call   <__stack_chk_fail@plt>
L14:
  mov    -0x8(%rbp),%rbx
  leave
  ret
```

assistant: ```c
int read_flag(int fd, const void *flag, const int flag_size, const int max_bytes) {
  char buff[flag_size];
  int left = 0;
  int bytes;
  int ret;
  int total_bytes = 0;
  while (1) {
    bytes = sizeof(buff) - left;
    if (left > 0)
      memmove(buff, &buff[bytes], left);
    if (recvn(fd, &buff[left], bytes, 0) != bytes)
      goto err;
    ret = search_flag(buff, sizeof(buff), flag, flag_size, &left);
    if (ret == 0)
      return 0;
    if (max_bytes == 0)
      continue;
    total_bytes += (bytes - left);
    if (total_bytes >= max_bytes)
      goto err;
  }
err:
  return -1;
}
```