user: Converte this assembly snippet into its equivalent C code:

```asm
<circle>:
  endbr64
  push   %r15
  lea    (%rdx,%rdx,1),%eax
  mov    $0x5,%r11d
  push   %r14
  sub    %eax,%r11d
  push   %r13
  mov    %edi,%r13d
  push   %r12
  mov    %edx,%r12d
  push   %rbp
  mov    %esi,%ebp
  lea    (%r12,%r13,1),%r14d
  push   %rbx
  mov    %ecx,%ebx
  mov    $0x1,%ecx
  lea    (%r12,%rbp,1),%r15d
  sub    %edx,%ecx
  sub    $0x28,%rsp
  mov    %esi,0x8(%rsp)
  sub    %edx,%esi
  mov    %ebx,%edx
  mov    %ecx,0x10(%rsp)
  mov    %r11d,0xc(%rsp)
  call   <plot@plt>
  mov    %ebx,%edx
  mov    %r15d,%esi
  mov    %r13d,%edi
  call   <plot@plt>
  mov    %ebx,%edx
  mov    %ebp,%esi
  mov    %r14d,%edi
  call   <plot@plt>
  mov    %r13d,%edi
  mov    %ebx,%edx
  mov    %ebp,%esi
  sub    %r12d,%edi
  call   <plot@plt>
  test   %r12d,%r12d
  mov    0xc(%rsp),%r11d
  mov    0x10(%rsp),%ecx
  jle    L13
  xor    %ebp,%ebp
  jmp    L37
  xchg   %ax,%ax
L2:
  mov    0x8(%rsp),%eax
  sub    $0x1,%r12d
  add    %r11d,%ecx
  add    $0x4,%r11d
  lea    (%r12,%r13,1),%r14d
  lea    (%r12,%rax,1),%r15d
L33:
  mov    0x8(%rsp),%r10d
  lea    0x0(%rbp,%r13,1),%r9d
  mov    %ebx,%edx
  mov    %ecx,0x18(%rsp)
  mov    %r9d,%edi
  mov    %r11d,0x1c(%rsp)
  sub    %r12d,%r10d
  mov    %r9d,0x10(%rsp)
  mov    %r10d,%esi
  mov    %r10d,0x14(%rsp)
  call   <plot@plt>
  mov    %r13d,%edi
  mov    %ebx,%edx
  mov    %r15d,%esi
  sub    %ebp,%edi
  mov    %edi,0xc(%rsp)
  call   <plot@plt>
  mov    0x14(%rsp),%esi
  mov    0xc(%rsp),%edi
  mov    %ebx,%edx
  call   <plot@plt>
  mov    0x10(%rsp),%edi
  mov    %ebx,%edx
  mov    %r15d,%esi
  call   <plot@plt>
  mov    0x8(%rsp),%r10d
  mov    %ebx,%edx
  mov    %r14d,%edi
  sub    %ebp,%r10d
  mov    %r10d,%esi
  mov    %r10d,0x14(%rsp)
  call   <plot@plt>
  mov    0x8(%rsp),%r10d
  mov    %r13d,%edi
  mov    %ebx,%edx
  sub    %r12d,%edi
  lea    (%r10,%rbp,1),%r9d
  mov    %edi,0xc(%rsp)
  mov    %r9d,%esi
  mov    %r9d,0x10(%rsp)
  call   <plot@plt>
  mov    0x14(%rsp),%esi
  mov    0xc(%rsp),%edi
  mov    %ebx,%edx
  call   <plot@plt>
  mov    0x10(%rsp),%esi
  mov    %ebx,%edx
  mov    %r14d,%edi
  call   <plot@plt>
  cmp    %ebp,%r12d
  mov    0x18(%rsp),%ecx
  mov    0x1c(%rsp),%r11d
  jle    L13
L37:
  lea    0x3(%rbp,%rbp,1),%eax
  add    $0x1,%ebp
  test   %ecx,%ecx
  jns    L2
  add    %eax,%ecx
  add    $0x2,%r11d
  jmp    L33
  nopl   (%rax)
L13:
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void circle(int xcent, int ycent, int rad, int colr) {
  int x, y, d;
  int dE, dSE;
  x = 0;
  y = rad;
  d = 1 - rad;
  dE = 3;
  dSE = -(rad << 1) + 5;
  plot(xcent - x, ycent - y, colr);
  plot(xcent - x, ycent + y, colr);
  plot(xcent + y, ycent - x, colr);
  plot(xcent - y, ycent + x, colr);
  while (y > x) {
    if (d < 0) {
      d += dE;
      dE += 2;
      dSE += 2;
      ++x;
    } else {
      d += dSE;
      dE += 2;
      dSE += 4;
      ++x;
      --y;
    }
    plot(xcent + x, ycent - y, colr);
    plot(xcent - x, ycent + y, colr);
    plot(xcent - x, ycent - y, colr);
    plot(xcent + x, ycent + y, colr);
    plot(xcent + y, ycent - x, colr);
    plot(xcent - y, ycent + x, colr);
    plot(xcent - y, ycent - x, colr);
    plot(xcent + y, ycent + x, colr);
  }
}
```