user: 下面的汇编指令对应的C源代码是什么：

```asm
<scan_ip6>:
  endbr64
  push   %r15
  pxor   %xmm0,%xmm0
  mov    $0x2,%r15d
  push   %r14
  xor    %r14d,%r14d
  push   %r13
  mov    %r14d,%r13d
  push   %r12
  xor    %r12d,%r12d
  push   %rbp
  mov    %rdi,%rbp
  push   %rbx
  mov    %rsi,%rbx
  sub    $0x58,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x48(%rsp)
  xor    %eax,%eax
  movups %xmm0,(%rsi)
  cmpb   $0x3a,0x0(%rbp)
  lea    0x28(%rsp),%rsi
  jne    L140
  cmpb   $0x3a,0x1(%rbp)
  je     L299
L168:
  add    $0x1,%r12d
  add    $0x1,%rbp
L140:
  mov    $0x10,%edx
  mov    %rbp,%rdi
  mov    %rsi,(%rsp)
  call   <strtoul@plt>
  mov    0x28(%rsp),%rdx
  mov    (%rsp),%rsi
  sub    %rbp,%rdx
  test   %edx,%edx
  mov    %edx,%r13d
  je     L238
  mov    %edx,%ecx
  lea    (%rcx,%rbp,1),%rdi
  cmp    $0xc,%r14
  je     L252
  movzbl %ah,%ecx
  mov    %al,0x1(%rbx,%r14,1)
  add    %edx,%r12d
  mov    %cl,(%rbx,%r14,1)
  cmp    $0x10,%r15d
  je     L201
L203:
  mov    %rdi,%rbp
  add    $0x2,%r14
  add    $0x2,%r15d
  cmpb   $0x3a,0x0(%rbp)
  mov    %r14d,%r13d
  jne    L140
  cmpb   $0x3a,0x1(%rbp)
  jne    L168
L299:
  lea    0x2(%rbp),%r15
  add    $0x2,%r12d
  lea    0x28(%rsp),%rcx
  xor    %r14d,%r14d
L77:
  cmpb   $0x3a,(%r15)
  mov    %r14d,%ebp
  je     L200
  test   %r14,%r14
  je     L81
L190:
  mov    $0x10,%eax
  movzbl 0x30(%rsp),%ecx
  sub    %ebp,%eax
  mov    %eax,%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x31(%rsp),%ecx
  lea    0x1(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0x2,%ebp
  je     L201
  movzbl 0x32(%rsp),%ecx
  lea    0x2(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x33(%rsp),%ecx
  lea    0x3(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0x4,%ebp
  je     L201
  movzbl 0x34(%rsp),%ecx
  lea    0x4(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x35(%rsp),%ecx
  lea    0x5(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0x6,%ebp
  je     L201
  movzbl 0x36(%rsp),%ecx
  lea    0x6(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x37(%rsp),%ecx
  lea    0x7(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0x8,%ebp
  je     L201
  movzbl 0x38(%rsp),%ecx
  lea    0x8(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x39(%rsp),%ecx
  lea    0x9(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0xa,%ebp
  je     L201
  movzbl 0x3a(%rsp),%ecx
  lea    0xa(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x3b(%rsp),%ecx
  lea    0xb(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0xc,%ebp
  je     L201
  movzbl 0x3c(%rsp),%ecx
  lea    0xc(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x3d(%rsp),%ecx
  lea    0xd(%rax),%edx
  mov    %cl,(%rbx,%rdx,1)
  cmp    $0xe,%ebp
  je     L201
  movzbl 0x3e(%rsp),%ecx
  lea    0xe(%rax),%edx
  add    $0xf,%eax
  mov    %cl,(%rbx,%rdx,1)
  movzbl 0x3f(%rsp),%edx
  mov    %dl,(%rbx,%rax,1)
  nopl   (%rax)
L201:
  mov    0x48(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L226
  add    $0x58,%rsp
  mov    %r12d,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  cs nopw 0x0(%rax,%rax,1)
L252:
  cmpb   $0x2e,(%rdi)
  je     L55
  mov    %ah,0xc(%rbx)
  add    %edx,%r12d
  mov    %al,0xd(%rbx)
  jmp    L203
  nopw   0x0(%rax,%rax,1)
L200:
  test   %r14,%r14
  je     L201
  add    $0x1,%r15
  add    $0x1,%r12d
  nopl   (%rax)
L81:
  mov    $0x10,%edx
  mov    %rcx,%rsi
  mov    %r15,%rdi
  mov    %rcx,(%rsp)
  call   <strtol@plt>
  mov    0x28(%rsp),%rdx
  mov    (%rsp),%rcx
  mov    %rax,%r8
  mov    %rdx,%r9
  sub    %r15,%r9
  cmp    %r15d,%edx
  je     L319
  mov    %r9d,%edx
  lea    0x0(%rbp,%r13,1),%eax
  add    %r15,%rdx
  cmp    $0xc,%eax
  jbe    L69
L156:
  add    $0x2,%ebp
  mov    %r8d,%eax
  add    %r9d,%r12d
  rol    $0x8,%ax
  lea    0x0(%r13,%rbp,1),%esi
  mov    %ax,0x30(%rsp,%r14,1)
  add    $0x2,%r14
  cmp    $0x10,%esi
  je     L190
L100:
  mov    %rdx,%r15
  jmp    L77
L69:
  cmpb   $0x2e,(%rdx)
  jne    L156
  lea    0x30(%rsp,%r14,1),%rsi
  mov    %r15,%rdi
  mov    %rcx,0x18(%rsp)
  mov    %rdx,0x10(%rsp)
  mov    %r8,0x8(%rsp)
  mov    %r9,(%rsp)
  call   <inet_aton@plt>
  mov    (%rsp),%r9
  mov    0x8(%rsp),%r8
  test   %rax,%rax
  mov    0x10(%rsp),%rdx
  mov    0x18(%rsp),%rcx
  jne    L294
  mov    %r8d,%eax
  mov    $0xc,%r13d
  add    %r9d,%r12d
  rol    $0x8,%ax
  sub    %ebp,%r13d
  mov    %ax,0x30(%rsp,%r14,1)
  add    $0x2,%r14
  jmp    L100
L55:
  lea    0xc(%rbx),%rsi
  mov    %rbp,%rdi
  add    %r13d,%r12d
  call   <inet_aton@plt>
  test   %rax,%rax
  jne    L201
L238:
  xor    %r12d,%r12d
  jmp    L201
L319:
  cmpb   $0x1,(%r15)
  adc    $0xffffffff,%r12d
  test   %ebp,%ebp
  je     L201
  jmp    L190
L294:
  mov    %r15,%rdi
  add    $0x4,%ebp
  call   <strlen@plt>
  add    %eax,%r12d
  jmp    L190
L226:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
unsigned int scan_ip6(const char *s, char ip[16]) {
  unsigned int i;
  unsigned int len = 0;
  unsigned long u;
  char suffix[16];
  unsigned int prefixlen = 0;
  unsigned int suffixlen = 0;
  for (i = 0; i < 16; i++)
    ip[i] = 0;
  for (;;) {
    if (*s == ':') {
      len++;
      if (s[1] == ':') {
        s += 2;
        len++;
        break;
      }
      s++;
    }
    {
      char *tmp;
      u = strtoul(s, &tmp, 16);
      i = tmp - s;
    }
    if (!i)
      return 0;
    if (prefixlen == 12 && s[i] == '.') {
      if (inet_aton(s, (struct in_addr *)(ip + 12)))
        return i + len;
      else
        return 0;
    }
    ip[prefixlen++] = (u >> 8);
    ip[prefixlen++] = (u & 255);
    s += i;
    len += i;
    if (prefixlen == 16)
      return len;
  }
  for (;;) {
    if (*s == ':') {
      if (suffixlen == 0)
        break;
      s++;
      len++;
    } else if (suffixlen != 0)
      break;
    {
      char *tmp;
      u = strtol(s, &tmp, 16);
      i = tmp - s;
    }
    if (!i) {
      if (*s)
        len--;
      break;
    }
    if (suffixlen + prefixlen <= 12 && s[i] == '.') {
      if (inet_aton(s, (struct in_addr *)(suffix + suffixlen))) {
        suffixlen += 4;
        len += strlen(s);
        break;
      } else
        prefixlen = 12 - suffixlen;
    }
    suffix[suffixlen++] = (u >> 8);
    suffix[suffixlen++] = (u & 255);
    s += i;
    len += i;
    if (prefixlen + suffixlen == 16)
      break;
  }
  for (i = 0; i < suffixlen; i++)
    ip[16 - suffixlen + i] = suffix[i];
  return len;
}
```