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

```asm
<decomment_c>:
  endbr64
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x1000,%rsp
  orq    $0x0,(%rsp)
  sub    $0x20,%rsp
  mov    %rsi,%r12
  mov    %fs:0x28,%rax
  mov    %rax,0x1018(%rsp)
  xor    %eax,%eax
  lea    0x10(%rsp),%rax
  mov    %rax,0x8(%rsp)
  mov    $0x0,%ebx
  lea    D8(%rip),%rbp
  jmp    L103
  cmp    $0x27,%eax
  je     L254
  cmp    $0x2f,%eax
  je     L207
  cmp    $0x22,%eax
  je     L146
  mov    0x8(%rsp),%rdx
  lea    0x1(%rdx),%rcx
  mov    %rcx,0x8(%rsp)
  mov    %al,(%rdx)
  jmp    L259
L254:
  mov    0x8(%rsp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,0x8(%rsp)
  movb   $0x27,(%rax)
  mov    $0x4,%ebx
  jmp    L259
L146:
  mov    0x8(%rsp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,0x8(%rsp)
  movb   $0x22,(%rax)
  mov    $0x3,%ebx
  jmp    L259
L207:
  mov    %r12,%rdi
  call   <getc@plt>
  mov    %eax,%edi
  cmp    $0x2f,%eax
  je     L85
  cmp    $0x80,%eax
  je     L259
  cmp    $0x2a,%eax
  je     L80
  mov    0x8(%rsp),%rax
  lea    0x1(%rax),%rdx
  mov    %rdx,0x8(%rsp)
  movb   $0x2f,(%rax)
  mov    %r12,%rsi
  call   <ungetc@plt>
  jmp    L259
  cmp    $0x2a,%eax
  jne    L259
  mov    %r12,%rdi
  call   <getc@plt>
  cmp    $0x2f,%eax
  jne    L305
  mov    $0x0,%ebx
  jmp    L259
L305:
  mov    %r12,%rsi
  mov    %eax,%edi
  call   <ungetc@plt>
  jmp    L259
  cmp    $0xa,%eax
  setne  %bl
  movzbl %bl,%ebx
  add    %ebx,%ebx
L259:
  mov    0x8(%rsp),%rax
  lea    0x10(%rsp),%rdx
  cmp    %rdx,%rax
  jbe    L103
  cmpb   $0xa,-0x1(%rax)
  je     L230
L103:
  mov    %r12,%rdi
  call   <getc@plt>
  cmp    $0x80,%eax
  je     L99
  cmp    $0x4,%ebx
  ja     L259
  mov    %ebx,%edx
  movslq 0x0(%rbp,%rdx,4),%rdx
  add    %rbp,%rdx
  notrack jmp *%rdx
  mov    0x8(%rsp),%rdx
  lea    0x1(%rdx),%rcx
  mov    %rcx,0x8(%rsp)
  mov    %al,(%rdx)
  cmp    $0x22,%eax
  je     L164
  cmp    $0x5c,%eax
  jne    L259
  mov    %r12,%rdi
  call   <getc@plt>
  mov    %eax,%edx
  mov    0x8(%rsp),%rax
  lea    0x1(%rax),%rcx
  mov    %rcx,0x8(%rsp)
  mov    %dl,(%rax)
  jmp    L259
  mov    0x8(%rsp),%rdx
  lea    0x1(%rdx),%rcx
  mov    %rcx,0x8(%rsp)
  mov    %al,(%rdx)
  cmp    $0x27,%eax
  je     L272
  cmp    $0x5c,%eax
  jne    L259
  mov    %r12,%rdi
  call   <getc@plt>
  jmp    L259
L85:
  mov    $0x2,%ebx
  jmp    L259
L80:
  mov    $0x1,%ebx
  jmp    L259
L164:
  mov    $0x0,%ebx
  jmp    L259
L272:
  mov    $0x0,%ebx
  jmp    L259
L230:
  lea    0x8(%rsp),%rsi
  mov    %rdx,%rdi
  call   <blankline@plt>
  jmp    L103
L99:
  mov    0x1018(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L142
  add    $0x1020,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  ret
L142:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
void decomment_c(const char *fname, FILE *in) {
  register int c, c1;
  char outbuf[4 * 1024];
  char *op = outbuf;
  enum { NORMAL, C_COMMENT, CC_COMMENT, STRINGLITERAL, CHARLITERAL } state = NORMAL;
  while ((c = getc(in)) != EOF) {
    switch (state) {
    case NORMAL:
      switch (c) {
      case '\'':
        state = CHARLITERAL;
        *op++ = c;
        break;
      case '"':
        state = STRINGLITERAL;
        *op++ = c;
        break;
      case '/':
        c1 = getc(in);
        switch (c1) {
        case '/':
          state = CC_COMMENT;
          break;
        case '*':
          state = C_COMMENT;
          break;
        case EOF:
          break;
        default:
          *op++ = c;
          ungetc(c1, in);
          break;
        }
        break;
      default:
        *op++ = c;
        break;
      }
      break;
    case C_COMMENT:
      if (c == '*') {
        c1 = getc(in);
        if (c1 == '/') {
          state = NORMAL;
        } else {
          ungetc(c1, in);
        }
      }
      break;
    case CC_COMMENT:
      if (c == '\n') {
        state = NORMAL;
      }
      break;
    case STRINGLITERAL:
      *op++ = c;
      switch (c) {
      case '"':
        state = NORMAL;
        break;
      case '\\':
        c1 = getc(in);
        *op++ = c1;
        break;
      }
      break;
    case CHARLITERAL:
      *op++ = c;
      switch (c) {
      case '\'':
        state = NORMAL;
        break;
      case '\\':
        getc(in);
        break;
      }
      break;
    }
    if (op > outbuf && op[-1] == '\n') {
      blankline(outbuf, &op);
    }
  };
}
```