user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<line>:
  endbr64
  push   %r15
  mov    %rcx,%r15
  push   %r14
  mov    %rsi,%r14
  push   %r13
  mov    $0x2,%r13d
  push   %r12
  mov    %rdi,%r12
  mov    %rdx,%rdi
  push   %rbp
  sub    %r12,%rdi
  push   %rbx
  mov    %r8d,%ebx
  sub    $0x18,%rsp
  mov    %rdx,0x8(%rsp)
  call   <abs@plt>
  mov    %r15,%rdi
  sub    %r14,%rdi
  mov    %eax,%ebp
  mov    %eax,(%rsp)
  call   <abs@plt>
  mov    0x8(%rsp),%rdx
  mov    %r12d,%edi
  mov    %r14d,%esi
  mov    %eax,0x4(%rsp)
  add    %eax,%ebp
  cmp    %r12,%rdx
  je     L186
  jb     L62
  cmp    %r14,%r15
  sbb    %r13d,%r13d
  and    $0x3,%r13d
  add    $0x1,%r13d
L186:
  xor    %r12d,%r12d
  xor    %r15d,%r15d
  test   %ebp,%ebp
  jg     L56
  jmp    L28
  nopl   (%rax)
L82:
  cmp    $0x3,%r13d
  je     L162
  cmp    $0x4,%r13d
  je     L111
  lea    0x1(%rdi),%r14d
  cmp    $0x2,%r13d
  je     L113
L58:
  mov    %ebx,%edx
  mov    %esi,0x8(%rsp)
  call   <putpixel@plt>
  mov    0x8(%rsp),%esi
  sub    0x4(%rsp),%r12d
  mov    %r14d,%edi
L24:
  add    $0x1,%r15d
  cmp    %r15d,%ebp
  je     L28
L56:
  test   %r12d,%r12d
  jns    L82
  cmp    $0x3,%r13d
  je     L33
  cmp    $0x4,%r13d
  je     L43
  lea    0x1(%rsi),%r14d
  cmp    $0x2,%r13d
  je     L126
L112:
  mov    %ebx,%edx
  add    $0x1,%r15d
  mov    %edi,0x8(%rsp)
  call   <putpixel@plt>
  mov    0x8(%rsp),%edi
  add    (%rsp),%r12d
  mov    %r14d,%esi
  cmp    %r15d,%ebp
  jne    L56
L28:
  add    $0x18,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nop
L113:
  lea    0x1(%rsi),%r14d
L69:
  mov    %ebx,%edx
  mov    %edi,0x8(%rsp)
  call   <putpixel@plt>
  mov    0x8(%rsp),%edi
  sub    (%rsp),%r12d
  mov    %r14d,%esi
  jmp    L24
  nopl   0x0(%rax)
L111:
  lea    -0x1(%rsi),%r14d
  jmp    L69
  cs nopw 0x0(%rax,%rax,1)
L162:
  lea    -0x1(%rdi),%r14d
  jmp    L58
  nopl   0x0(%rax)
L126:
  lea    -0x1(%rdi),%r14d
L94:
  mov    %ebx,%edx
  mov    %esi,0x8(%rsp)
  call   <putpixel@plt>
  mov    0x8(%rsp),%esi
  add    0x4(%rsp),%r12d
  mov    %r14d,%edi
  jmp    L24
L43:
  lea    0x1(%rdi),%r14d
  jmp    L94
  cs nopw 0x0(%rax,%rax,1)
L33:
  lea    -0x1(%rsi),%r14d
  jmp    L112
  nopl   0x0(%rax)
L62:
  cmp    %r14,%r15
  sbb    %r13d,%r13d
  and    $0x2,%r13d
  add    $0x2,%r13d
  jmp    L186
```

assistant: ```c
void line(unsigned long x0, unsigned long y0, unsigned long x1, unsigned long y1, unsigned int color) {
  int dx, dy, n, k, i, f;
  int x, y;
  dx = abs(x1 - x0);
  dy = abs(y1 - y0);
  n = dx + dy;
  if (x1 == x0) {
    k = 2;
    x = x0;
    y = y0;
  } else if (x1 >= x0) {
    k = y1 >= y0 ? 1 : 4;
    x = x0;
    y = y0;
  } else {
    k = y1 >= y0 ? 2 : 4;
    x = x0;
    y = y0;
  }
  for (i = 0, f = 0; i < n; i++)
    if (f >= 0)
      switch (k) {
      case 1:
        putpixel(x++, y, color);
        f -= dy;
        break;
      case 2:
        putpixel(x, y++, color);
        f -= dx;
        break;
      case 3:
        putpixel(x--, y, color);
        f -= dy;
        break;
      case 4:
        putpixel(x, y--, color);
        f -= dx;
        break;
      }
    else
      switch (k) {
      case 1:
        putpixel(x, y++, color);
        f += dx;
        break;
      case 2:
        putpixel(x--, y, color);
        f += dy;
        break;
      case 3:
        putpixel(x, y--, color);
        f += dx;
        break;
      case 4:
        putpixel(x++, y, color);
        f += dy;
        break;
      }
}
```