user: What is the c source code of the assembly code below:

```asm
<RGB32toBGR32>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r13
  push   %r12
  push   %rbx
  sub    $0x68,%rsp
  mov    %rdi,-0x58(%rbp)
  mov    %esi,-0x5c(%rbp)
  mov    %edx,-0x60(%rbp)
  mov    %ecx,-0x64(%rbp)
  mov    %r8d,-0x68(%rbp)
  mov    %r9d,-0x6c(%rbp)
  mov    0x20(%rbp),%rax
  mov    %rax,-0x78(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x28(%rbp)
  xor    %eax,%eax
  mov    -0x6c(%rbp),%r9d
  mov    -0x68(%rbp),%r8d
  mov    -0x64(%rbp),%ecx
  mov    -0x60(%rbp),%edx
  mov    -0x5c(%rbp),%esi
  mov    -0x58(%rbp),%rax
  lea    -0x4c(%rbp),%rdi
  push   %rdi
  lea    -0x50(%rbp),%rdi
  push   %rdi
  mov    0x58(%rbp),%edi
  push   %rdi
  mov    0x50(%rbp),%edi
  push   %rdi
  mov    0x48(%rbp),%edi
  push   %rdi
  mov    0x40(%rbp),%edi
  push   %rdi
  mov    0x38(%rbp),%edi
  push   %rdi
  mov    0x30(%rbp),%edi
  push   %rdi
  mov    0x28(%rbp),%edi
  push   %rdi
  push   -0x78(%rbp)
  mov    0x18(%rbp),%edi
  push   %rdi
  mov    0x10(%rbp),%edi
  push   %rdi
  mov    %rax,%rdi
  call   <chk_args@plt>
  add    $0x60,%rsp
  test   %eax,%eax
  jne    L53
  mov    $0xffffffff,%eax
  jmp    L109
L53:
  cmpl   $0x0,0x38(%rbp)
  jns    L24
  mov    0x30(%rbp),%eax
  sub    $0x1,%eax
  imul   0x38(%rbp),%eax
  cltq
  neg    %rax
  add    %rax,-0x78(%rbp)
L24:
  cmpl   $0x0,-0x64(%rbp)
  jns    L156
  mov    -0x60(%rbp),%eax
  sub    $0x1,%eax
  imul   -0x64(%rbp),%eax
  cltq
  neg    %rax
  add    %rax,-0x58(%rbp)
L156:
  mov    -0x50(%rbp),%eax
  cmp    $0x1,%eax
  jne    L143
  mov    -0x4c(%rbp),%eax
  cmp    $0x1,%eax
  jne    L143
  mov    0x40(%rbp),%eax
  shl    $0x2,%eax
  movslq %eax,%rdx
  mov    0x48(%rbp),%eax
  imul   0x38(%rbp),%eax
  cltq
  add    %rax,%rdx
  mov    -0x78(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x48(%rbp)
  mov    -0x68(%rbp),%eax
  shl    $0x2,%eax
  movslq %eax,%rdx
  mov    -0x6c(%rbp),%eax
  imul   -0x64(%rbp),%eax
  cltq
  add    %rax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x40(%rbp)
  mov    $0x0,%r13d
  jmp    L14
L102:
  mov    0x10(%rbp),%ebx
  jmp    L71
L50:
  mov    -0x48(%rbp),%rax
  mov    (%rax),%r12d
  mov    %r12d,%eax
  shl    $0x10,%eax
  and    $0xff0000,%eax
  mov    %eax,%edx
  mov    %r12d,%eax
  and    $0xff00,%eax
  or     %eax,%edx
  mov    %r12d,%eax
  shr    $0x10,%eax
  movzbl %al,%eax
  or     %eax,%edx
  mov    -0x40(%rbp),%rax
  mov    %edx,(%rax)
  addq   $0x4,-0x48(%rbp)
  addq   $0x4,-0x40(%rbp)
  sub    $0x1,%ebx
L71:
  test   %ebx,%ebx
  jne    L50
  mov    0x10(%rbp),%eax
  lea    0x0(,%rax,4),%edx
  mov    0x38(%rbp),%eax
  sub    %edx,%eax
  cltq
  add    %rax,-0x48(%rbp)
  mov    0x10(%rbp),%eax
  lea    0x0(,%rax,4),%edx
  mov    -0x64(%rbp),%eax
  sub    %edx,%eax
  cltq
  add    %rax,-0x40(%rbp)
  add    $0x1,%r13d
L14:
  cmp    0x18(%rbp),%r13d
  jl     L102
  mov    $0x0,%eax
  jmp    L109
L143:
  mov    -0x50(%rbp),%eax
  cmp    $0x2,%eax
  jne    L90
  mov    -0x4c(%rbp),%eax
  cmp    $0x2,%eax
  jne    L90
  mov    0x40(%rbp),%eax
  shl    $0x2,%eax
  movslq %eax,%rdx
  mov    0x48(%rbp),%eax
  imul   0x38(%rbp),%eax
  cltq
  add    %rax,%rdx
  mov    -0x78(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x38(%rbp)
  mov    -0x68(%rbp),%eax
  shl    $0x2,%eax
  movslq %eax,%rdx
  mov    -0x6c(%rbp),%eax
  imul   -0x64(%rbp),%eax
  cltq
  add    %rax,%rdx
  mov    -0x58(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x30(%rbp)
  mov    $0x0,%r13d
  jmp    L91
L36:
  mov    0x50(%rbp),%ebx
  jmp    L87
L105:
  mov    -0x38(%rbp),%rax
  mov    (%rax),%r12d
  mov    %r12d,%eax
  shl    $0x10,%eax
  and    $0xff0000,%eax
  mov    %eax,%edx
  mov    %r12d,%eax
  and    $0xff00,%eax
  or     %eax,%edx
  mov    %r12d,%eax
  shr    $0x10,%eax
  movzbl %al,%eax
  or     %eax,%edx
  mov    %edx,%r12d
  mov    -0x30(%rbp),%rax
  mov    %r12d,(%rax)
  mov    -0x30(%rbp),%rax
  add    $0x4,%rax
  mov    %r12d,(%rax)
  addq   $0x8,-0x30(%rbp)
  addq   $0x4,-0x38(%rbp)
  sub    $0x1,%ebx
L87:
  test   %ebx,%ebx
  jne    L105
  mov    0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  neg    %rax
  add    %rax,-0x38(%rbp)
  mov    0x50(%rbp),%eax
  shl    $0x3,%eax
  cltq
  neg    %rax
  add    %rax,-0x30(%rbp)
  mov    0x50(%rbp),%eax
  lea    0x0(,%rax,8),%edx
  mov    -0x64(%rbp),%eax
  movslq %eax,%rcx
  mov    -0x30(%rbp),%rax
  add    %rax,%rcx
  mov    -0x30(%rbp),%rax
  mov    %rax,%rsi
  mov    %rcx,%rdi
  call   <memcpy@plt>
  mov    0x38(%rbp),%eax
  cltq
  add    %rax,-0x38(%rbp)
  mov    -0x64(%rbp),%eax
  add    %eax,%eax
  cltq
  add    %rax,-0x30(%rbp)
  add    $0x1,%r13d
L91:
  cmp    0x58(%rbp),%r13d
  jl     L36
  mov    $0x0,%eax
  jmp    L109
L90:
  mov    $0xffffffff,%eax
L109:
  mov    -0x28(%rbp),%rdx
  sub    %fs:0x28,%rdx
  je     L153
  call   <__stack_chk_fail@plt>
L153:
  lea    -0x18(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %rbp
  ret
```

assistant: ```c
int RGB32toBGR32(unsigned char *dest_ptr, int dest_width, int dest_height, int dest_pitch, int dest_x, int dest_y, int dest_dx, int dest_dy, unsigned char *src_ptr, int src_width, int src_height, int src_pitch, int src_x, int src_y, int src_dx, int src_dy) {
  int scale_x, scale_y;
  if (!chk_args(dest_ptr, dest_width, dest_height, dest_pitch, dest_x, dest_y, dest_dx, dest_dy, src_ptr, src_width, src_height, src_pitch, src_x, src_y, src_dx, src_dy, &scale_x, &scale_y))
    return -1;
  if (src_pitch < 0)
    src_ptr -= (src_height - 1) * src_pitch;
  if (dest_pitch < 0)
    dest_ptr -= (dest_height - 1) * dest_pitch;
  if (scale_x == 1 && scale_y == 1) {
    unsigned char *s, *d;
    register int i;
    s = src_ptr + src_x * 4 + src_y * src_pitch;
    d = dest_ptr + dest_x * 4 + dest_y * dest_pitch;
    for (i = 0; i < dest_dy; i++) {
      register int ddx = dest_dx;
      while (ddx) {
        register unsigned int a;
        a = *(unsigned int *)s;
        *(unsigned int *)d = ((a & 0x000000ff) << 16) | ((a & 0x0000ff00) << 0) | ((a & 0x00ff0000) >> 16);
        s += 4;
        d += 4;
        ddx--;
      }
      s += src_pitch - dest_dx * 4;
      d += dest_pitch - dest_dx * 4;
    }
    return 0;
  }
  if (scale_x == 2 && scale_y == 2) {
    unsigned char *s, *d;
    register int i;
    s = src_ptr + src_x * 4 + src_y * src_pitch;
    d = dest_ptr + dest_x * 4 + dest_y * dest_pitch;
    for (i = 0; i < src_dy; i++) {
      register int sdx = src_dx;
      while (sdx) {
        register unsigned int a, c;
        a = *(unsigned int *)s;
        c = ((a & 0x000000ff) << 16) | ((a & 0x0000ff00) << 0) | ((a & 0x00ff0000) >> 16);
        *(unsigned int *)d = c;
        *(unsigned int *)(d + 4) = c;
        d += 2 * 4;
        s += 4;
        sdx--;
      }
      s -= src_dx * 4;
      d -= src_dx * 2 * 4;
      memcpy(d + dest_pitch, d, src_dx * 2 * 4);
      s += src_pitch;
      d += dest_pitch * 2;
    }
    return 0;
  }
  return -1;
}
```