user: 请将以下的汇编代码转换成C语言代码：

```asm
<jam_atol_hex>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %rdi,-0x18(%rbp)
  movq   $0x0,-0x8(%rbp)
  movl   $0x0,-0xc(%rbp)
  jmp    L92
L95:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  jle    L139
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x39,%al
  jg     L139
  mov    -0x8(%rbp),%rax
  shl    $0x4,%rax
  mov    %rax,%rcx
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x30,%eax
  cltq
  add    %rcx,%rax
  mov    %rax,-0x8(%rbp)
  jmp    L9
L139:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  jle    L130
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x46,%al
  jg     L130
  mov    -0x8(%rbp),%rax
  shl    $0x4,%rax
  lea    0xa(%rax),%rcx
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x41,%eax
  cltq
  add    %rcx,%rax
  mov    %rax,-0x8(%rbp)
  jmp    L9
L130:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x60,%al
  jle    L9
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x66,%al
  jg     L9
  mov    -0x8(%rbp),%rax
  shl    $0x4,%rax
  lea    0xa(%rax),%rcx
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x61,%eax
  cltq
  add    %rcx,%rax
  mov    %rax,-0x8(%rbp)
L9:
  addl   $0x1,-0xc(%rbp)
L92:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2f,%al
  jle    L49
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x39,%al
  jle    L95
L49:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x40,%al
  jle    L26
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x46,%al
  jle    L95
L26:
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x60,%al
  jle    L22
  mov    -0xc(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x66,%al
  jle    L95
L22:
  mov    -0x8(%rbp),%rax
  pop    %rbp
  ret
```

assistant: ```c
long jam_atol_hex(char *string) {
  long result = 0L;
  int index = 0;
  while (((string[index] >= '0') && (string[index] <= '9')) || ((string[index] >= 'A') && (string[index] <= 'F')) || ((string[index] >= 'a') && (string[index] <= 'f'))) {
    if ((string[index] >= '0') && (string[index] <= '9')) {
      result = (result << 4) + (string[index] - '0');
    } else if ((string[index] >= 'A') && (string[index] <= 'F')) {
      result = (result << 4) + 10 + (string[index] - 'A');
    } else if ((string[index] >= 'a') && (string[index] <= 'f')) {
      result = (result << 4) + 10 + (string[index] - 'a');
    }
    ++index;
  }
  return (result);
}
```