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

```asm
<metaparse>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %rdi,%rbx
  mov    %fs:0x28,%rax
  mov    %rax,0x18(%rsp)
  xor    %eax,%eax
  movzbl (%rdi),%eax
  test   %al,%al
  jne    L185
L173:
  mov    0x18(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L164
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L146:
  lea    0x2(%rbx),%r14
  movb   $0x0,0x14(%rsp)
  mov    $0x0,%r12d
  movb   $0x0,0xe(%rsp)
L181:
  mov    %r12b,0xf(%rsp)
  movzbl (%r14),%r15d
  movsbl %r15b,%edi
  call   <isxdigit@plt>
  test   %eax,%eax
  je     L24
  cmp    $0x1,%r12b
  jg     L176
  add    $0x1,%r14
  mov    %r15b,0x15(%rsp,%r12,1)
  add    $0x1,%r12
  movb   $0x1,0xe(%rsp)
  jmp    L181
L24:
  cmpb   $0x0,0xe(%rsp)
  je     L107
  mov    %r12b,0x14(%rsp)
L110:
  movzbl 0x14(%rsp),%eax
  test   %al,%al
  jne    L16
L107:
  mov    %r13b,(%rbx)
  mov    %r14,%rsi
  mov    %rbp,%rdi
  call   <strcpy@plt>
  mov    %rbx,%rbp
  jmp    L35
L176:
  cmpb   $0x0,0xe(%rsp)
  je     L107
  movzbl 0xf(%rsp),%eax
  mov    %al,0x14(%rsp)
  jmp    L110
L16:
  movsbq %al,%rax
  movb   $0x0,0x15(%rsp,%rax,1)
  lea    0x14(%rsp),%rdx
  lea    0x15(%rsp),%rdi
  lea    D13(%rip),%rsi
  mov    $0x0,%eax
  call   <sscanf@plt>
  movzbl 0x14(%rsp),%r13d
  jmp    L107
  movb   $0x0,(%rbx)
L11:
  lea    0x2(%rbx),%rsi
  mov    %rbp,%rdi
  call   <strcpy@plt>
  mov    %rbx,%rbp
L35:
  lea    0x1(%rbp),%rbx
  movzbl 0x1(%rbp),%eax
  test   %al,%al
  je     L173
L185:
  mov    %rbx,%rbp
  cmp    $0x5c,%al
  jne    L35
  lea    0x1(%rbx),%rbp
  movzbl 0x1(%rbx),%r13d
  cmp    $0x78,%r13b
  je     L146
  sub    $0x30,%r13d
  cmp    $0x46,%r13b
  ja     L35
  movzbl %r13b,%r13d
  lea    D16(%rip),%rcx
  movslq (%rcx,%r13,4),%rax
  add    %rcx,%rax
  notrack jmp *%rax
  movb   $0x7,(%rbx)
  jmp    L11
  movb   $0x8,(%rbx)
  jmp    L11
  movb   $0x9,(%rbx)
  jmp    L11
  movb   $0xa,(%rbx)
  jmp    L11
  movb   $0xb,(%rbx)
  jmp    L11
  movb   $0xc,(%rbx)
  jmp    L11
  movb   $0xd,(%rbx)
  jmp    L11
  movb   $0x1b,(%rbx)
  jmp    L11
L164:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: disassemble_data
arguments: data_tag: D13
data_type: string

tool: D13: %x

assistant: ```c
void metaparse(s) char *s;
{
  char *t;
  char mod;
  for (t = s; *t; t++)
    if (*t == '\\') {
      t++;
      if (*t == 'x') {
        char num[3], i, *tt;
        tt = t++ - 1;
        i = 0;
        while (isxdigit(*t) && i < 2)
          num[i++] = *t++;
        if (i) {
          num[i] = 0;
          sscanf(num, "%x", &i);
          *tt = (char)i;
        } else
          *tt = 'x';
        strcpy(++tt, t);
        t = tt - 1;
      } else {
        mod = 1;
        switch (*t) {
        case '0':
          *(--t) = 0;
          break;
        case 'a':
          *(--t) = 7;
          break;
        case 'b':
          *(--t) = 8;
          break;
        case 't':
          *(--t) = 9;
          break;
        case 'n':
          *(--t) = 10;
          break;
        case 'v':
          *(--t) = 11;
          break;
        case 'f':
          *(--t) = 12;
          break;
        case 'r':
          *(--t) = 13;
          break;
        case 'E':
          *(--t) = 27;
          break;
        case '\\':
          --t;
          break;
        default:
          mod = 0;
        }
        if (mod)
          strcpy(t + 1, t + 2);
      }
    }
}
```