user: Please show me the C implementation that matches the assembly code listed below:

```asm
<i2c_ASN1_INTEGER>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x40,%rsp
  mov    %rdi,-0x38(%rbp)
  mov    %rsi,-0x40(%rbp)
  movl   $0x0,-0x20(%rbp)
  movb   $0x0,-0x21(%rbp)
  cmpq   $0x0,-0x38(%rbp)
  jne    L269
  mov    $0x0,%eax
  jmp    L186
L269:
  mov    -0x38(%rbp),%rax
  mov    (%rax),%edx
  mov    D8(%rip),%rax
  mov    (%rax),%eax
  and    %edx,%eax
  mov    %eax,-0x14(%rbp)
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  test   %eax,%eax
  jne    L184
  movl   $0x1,-0x1c(%rbp)
  jmp    L287
L184:
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  mov    %eax,-0x1c(%rbp)
  mov    -0x38(%rbp),%rax
  mov    0x8(%rax),%rax
  mov    (%rax),%eax
  mov    %eax,-0x18(%rbp)
  cmpl   $0x1,-0x1c(%rbp)
  jne    L98
  cmpl   $0x0,-0x18(%rbp)
  jne    L98
  movl   $0x0,-0x14(%rbp)
L98:
  cmpl   $0x0,-0x14(%rbp)
  jne    L241
  cmpl   $0x7f,-0x18(%rbp)
  jle    L241
  movl   $0x1,-0x20(%rbp)
  movb   $0x0,-0x21(%rbp)
  jmp    L77
L241:
  cmpl   $0x0,-0x14(%rbp)
  je     L77
  cmpl   $0x80,-0x18(%rbp)
  jle    L158
  movl   $0x1,-0x20(%rbp)
  movb   $0xff,-0x21(%rbp)
  jmp    L77
L158:
  cmpl   $0x80,-0x18(%rbp)
  jne    L77
  movl   $0x1,-0x18(%rbp)
  jmp    L113
L221:
  mov    -0x38(%rbp),%rax
  mov    0x8(%rax),%rdx
  mov    -0x18(%rbp),%eax
  cltq
  shl    $0x2,%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  test   %eax,%eax
  je     L116
  movl   $0x1,-0x20(%rbp)
  movb   $0xff,-0x21(%rbp)
  jmp    L77
L116:
  addl   $0x1,-0x18(%rbp)
L113:
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  cmp    %eax,-0x18(%rbp)
  jl     L221
L77:
  mov    -0x20(%rbp),%eax
  add    %eax,-0x1c(%rbp)
L287:
  cmpq   $0x0,-0x40(%rbp)
  jne    L243
  mov    -0x1c(%rbp),%eax
  jmp    L186
L243:
  mov    -0x40(%rbp),%rax
  mov    (%rax),%rax
  mov    %rax,-0x10(%rbp)
  cmpl   $0x0,-0x20(%rbp)
  je     L34
  mov    -0x10(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x10(%rbp)
  movzbl -0x21(%rbp),%edx
  mov    %dl,(%rax)
L34:
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  test   %eax,%eax
  jne    L90
  mov    -0x10(%rbp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,-0x10(%rbp)
  movb   $0x0,(%rax)
  jmp    L262
L90:
  cmpl   $0x0,-0x14(%rbp)
  jne    L170
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  mov    %eax,%edx
  mov    -0x38(%rbp),%rax
  mov    0x8(%rax),%rcx
  mov    -0x10(%rbp),%rax
  mov    %rcx,%rsi
  mov    %rax,%rdi
  call   <memcpy@plt>
  jmp    L262
L170:
  mov    -0x38(%rbp),%rax
  mov    0x8(%rax),%rdx
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  cltq
  shl    $0x2,%rax
  sub    $0x4,%rax
  add    %rdx,%rax
  mov    %rax,-0x8(%rbp)
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  cltq
  sub    $0x1,%rax
  add    %rax,-0x10(%rbp)
  mov    -0x38(%rbp),%rax
  mov    0x4(%rax),%eax
  mov    %eax,-0x18(%rbp)
  jmp    L51
L139:
  mov    -0x10(%rbp),%rax
  lea    -0x1(%rax),%rdx
  mov    %rdx,-0x10(%rbp)
  movb   $0x0,(%rax)
  subq   $0x1,-0x8(%rbp)
  subl   $0x1,-0x18(%rbp)
L51:
  mov    -0x8(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L125
  cmpl   $0x1,-0x18(%rbp)
  jg     L139
L125:
  mov    -0x8(%rbp),%rax
  lea    -0x1(%rax),%rdx
  mov    %rdx,-0x8(%rbp)
  movzbl (%rax),%ecx
  mov    -0x10(%rbp),%rax
  lea    -0x1(%rax),%rdx
  mov    %rdx,-0x10(%rbp)
  neg    %ecx
  mov    %ecx,%edx
  mov    %dl,(%rax)
  subl   $0x1,-0x18(%rbp)
  jmp    L200
L27:
  mov    -0x8(%rbp),%rax
  lea    -0x1(%rax),%rdx
  mov    %rdx,-0x8(%rbp)
  movzbl (%rax),%ecx
  mov    -0x10(%rbp),%rax
  lea    -0x1(%rax),%rdx
  mov    %rdx,-0x10(%rbp)
  not    %ecx
  mov    %ecx,%edx
  mov    %dl,(%rax)
  subl   $0x1,-0x18(%rbp)
L200:
  cmpl   $0x0,-0x18(%rbp)
  jg     L27
L262:
  mov    -0x40(%rbp),%rax
  mov    (%rax),%rdx
  mov    -0x1c(%rbp),%eax
  cltq
  add    %rax,%rdx
  mov    -0x40(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x1c(%rbp),%eax
L186:
  leave
  ret
```

assistant: ```c
int i2c_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **pp) {
  int pad = 0, ret, i, neg;
  unsigned char *p, *n, pb = 0;
  if (a == NULL)
    return (0);
  neg = a->type & V_ASN1_NEG;
  if (a->length == 0)
    ret = 1;
  else {
    ret = a->length;
    i = a->data[0];
    if (ret == 1 && i == 0)
      neg = 0;
    if (!neg && (i > 127)) {
      pad = 1;
      pb = 0;
    } else if (neg) {
      if (i > 128) {
        pad = 1;
        pb = 0xFF;
      } else if (i == 128) {
        for (i = 1; i < a->length; i++)
          if (a->data[i]) {
            pad = 1;
            pb = 0xFF;
            break;
          }
      }
    }
    ret += pad;
  }
  if (pp == NULL)
    return (ret);
  p = *pp;
  if (pad)
    *(p++) = pb;
  if (a->length == 0)
    *(p++) = 0;
  else if (!neg)
    memcpy(p, a->data, (unsigned int)a->length);
  else {
    n = a->data + a->length - 1;
    p += a->length - 1;
    i = a->length;
    while (!*n && i > 1) {
      *(p--) = 0;
      n--;
      i--;
    }
    *(p--) = ((*(n--)) ^ 0xff) + 1;
    i--;
    for (; i > 0; i--)
      *(p--) = *(n--) ^ 0xff;
  }
  *pp += ret;
  return (ret);
}
```