user: 请显示与下面列出的汇编代码相匹配的C语言实现:

```asm
<set_hw_addr>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x20,%rsp
  mov    %rdi,-0x18(%rbp)
  mov    %rsi,-0x20(%rbp)
  movl   $0x0,-0x4(%rbp)
  jmp    L140
L38:
  mov    -0x20(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x20(%rbp)
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <tolower@plt>
  mov    %al,-0x5(%rbp)
  cmpb   $0x0,-0x5(%rbp)
  jne    L16
  lea    D29(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <perror@plt>
  mov    $0x1,%edi
  call   <exit@plt>
L16:
  movsbl -0x5(%rbp),%eax
  sub    $0x30,%eax
  cmp    $0x9,%eax
  ja     L85
  movzbl -0x5(%rbp),%eax
  sub    $0x30,%eax
  mov    %al,-0x6(%rbp)
  jmp    L135
L85:
  cmpb   $0x60,-0x5(%rbp)
  jle    L134
  cmpb   $0x66,-0x5(%rbp)
  jg     L134
  movzbl -0x5(%rbp),%eax
  sub    $0x57,%eax
  mov    %al,-0x6(%rbp)
  jmp    L135
L134:
  lea    D29(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <perror@plt>
  mov    $0x1,%edi
  call   <exit@plt>
L135:
  movsbl -0x6(%rbp),%eax
  shl    $0x4,%eax
  mov    %eax,%ecx
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  mov    %ecx,%edx
  mov    %dl,(%rax)
  mov    -0x20(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x20(%rbp)
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <tolower@plt>
  mov    %al,-0x5(%rbp)
  cmpb   $0x0,-0x5(%rbp)
  jne    L3
  lea    D29(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <perror@plt>
  mov    $0x1,%edi
  call   <exit@plt>
L3:
  movsbl -0x5(%rbp),%eax
  sub    $0x30,%eax
  cmp    $0x9,%eax
  ja     L47
  movzbl -0x5(%rbp),%eax
  sub    $0x30,%eax
  mov    %al,-0x6(%rbp)
  jmp    L125
L47:
  cmpb   $0x60,-0x5(%rbp)
  jle    L128
  cmpb   $0x66,-0x5(%rbp)
  jg     L128
  movzbl -0x5(%rbp),%eax
  sub    $0x57,%eax
  mov    %al,-0x6(%rbp)
  jmp    L125
L128:
  lea    D29(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <perror@plt>
  mov    $0x1,%edi
  call   <exit@plt>
L125:
  mov    -0x4(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  mov    -0x4(%rbp),%edx
  movslq %edx,%rcx
  mov    -0x18(%rbp),%rdx
  add    %rcx,%rdx
  or     -0x6(%rbp),%al
  mov    %al,(%rdx)
  mov    -0x20(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x3a,%al
  jne    L108
  addq   $0x1,-0x20(%rbp)
L108:
  addl   $0x1,-0x4(%rbp)
L140:
  cmpl   $0x5,-0x4(%rbp)
  jle    L38
  nop
  nop
  leave
  ret
```

tool_calls: name: read_data
arguments: data_label: D29
datatype: string

tool: D29: Invalid hardware address

assistant: ```c
void set_hw_addr(char buf[], char *str) {
  int i;
  char c, val;
  for (i = 0; i < 6; i++) {
    if (!(c = tolower(*str++)))
      perror("Invalid hardware address"), exit(1);
    if (isdigit(c))
      val = c - '0';
    else if (c >= 'a' && c <= 'f')
      val = c - 'a' + 10;
    else
      perror("Invalid hardware address"), exit(1);
    buf[i] = val << 4;
    if (!(c = tolower(*str++)))
      perror("Invalid hardware address"), exit(1);
    if (isdigit(c))
      val = c - '0';
    else if (c >= 'a' && c <= 'f')
      val = c - 'a' + 10;
    else
      perror("Invalid hardware address"), exit(1);
    buf[i] |= val;
    if (*str == ':')
      str++;
  }
}
```