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

```asm
<buildfname>:
  endbr64
  push   %r15
  mov    %rdi,%r15
  push   %r14
  push   %r13
  push   %r12
  mov    %rsi,%r12
  push   %rbp
  push   %rbx
  sub    $0x18,%rsp
  movzbl (%rdi),%ebx
  mov    %rdx,(%rsp)
  mov    %ecx,0xc(%rsp)
  cmp    $0x2a,%bl
  jne    L22
  movzbl 0x1(%rdi),%ebx
  add    $0x1,%r15
L22:
  cmp    $0x3b,%bl
  ja     L25
  movabs $0xf7ffefdffffffffe,%rax
  bt     %rbx,%rax
  jae    L98
L25:
  mov    %ebx,%eax
  mov    %r15,%r13
  xor    %r14d,%r14d
  movabs $0xf7ffefdffffffffe,%rbp
  nopl   0x0(%rax,%rax,1)
L65:
  cmp    $0x26,%al
  je     L105
  add    $0x1,%r14d
L135:
  movzbl 0x1(%r13),%eax
  add    $0x1,%r13
  cmp    $0x3b,%al
  ja     L65
  bt     %rax,%rbp
  jb     L65
  cmp    0xc(%rsp),%r14d
  jge    L134
  mov    (%rsp),%rbp
  mov    $0x8,%r13d
  lea    D1(%rip),%rdx
  movabs $0xf7ffefdffffffffe,%r14
  nopl   0x0(%rax)
L45:
  cmp    $0x26,%bl
  je     L26
  mov    %bl,0x0(%rbp)
  add    $0x1,%rbp
L99:
  movzbl 0x1(%r15),%ebx
  add    $0x1,%r15
  cmp    $0x3b,%bl
  ja     L45
  bt     %rbx,%r14
  jb     L45
L100:
  movb   $0x0,0x0(%rbp)
  add    $0x18,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L105:
  mov    %r12,%rdi
  call   <strlen@plt>
  add    %eax,%r14d
  jmp    L135
L26:
  mov    %rbp,%rax
  mov    %r13,%rsi
  sub    (%rsp),%rax
  mov    %r12,%rcx
  sub    %rax,%rsi
  mov    %rbp,%rdi
  xor    %eax,%eax
  call   <snprintf@plt>
  movsbl 0x0(%rbp),%edi
  call   <toupper@plt>
  mov    %rbp,%rdi
  mov    %al,0x0(%rbp)
  call   <strlen@plt>
  lea    D1(%rip),%rdx
  add    %rax,%rbp
  jmp    L99
  nopw   0x0(%rax,%rax,1)
L134:
  movslq 0xc(%rsp),%rsi
  mov    (%rsp),%rdi
  add    $0x18,%rsp
  mov    %r15,%rcx
  pop    %rbx
  lea    D1(%rip),%rdx
  pop    %rbp
  xor    %eax,%eax
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  jmp    1090 <snprintf@plt>
  nopl   0x0(%rax,%rax,1)
L98:
  mov    0xc(%rsp),%eax
  test   %eax,%eax
  jle    L134
  mov    (%rsp),%rbp
  jmp    L100
```

tool_calls: name: unpack_data
arguments: label: D1
type_infered: string

tool: D1: %s

assistant: ```c
void buildfname(gecos, login, buf, buflen) register char *gecos;
char *login;
char *buf;
int buflen;
{
  register char *p;
  register char *bp = buf;
  int l;
  if (*gecos == '*')
    gecos++;
  l = 0;
  for (p = gecos; *p != '\0' && *p != ',' && *p != ';' && *p != '%'; p++) {
    if (*p == '&')
      l += strlen(login);
    else
      l++;
  }
  if (l > buflen - 1) {
    if (0)
      printf("snprintf (buf, buflen, format, gecos)\n");
    if (0)
      printf("sizeof (buf) = %d\n", sizeof(buf));
    if (0)
      printf("buflen = %d\n", buflen);
    if (0)
      printf("strlen (gecos)=%d\n", strlen(gecos));
    snprintf(buf, buflen, "%s", gecos);
    return;
  }
  for (p = gecos; *p != '\0' && *p != ',' && *p != ';' && *p != '%'; p++) {
    if (*p == '&') {
      if (0)
        printf("snprintf(bp, SPACELEFT(buf, bp), format, login)\n");
      if (0)
        printf("sizeof(bp) = %d\n", sizeof(bp));
      if (0)
        printf("SPACELEFT(buf,bp)=%d\n", (sizeof buf - ((bp)-buf)));
      if (0)
        printf("strlen(login)=%d\n", strlen(login));
      snprintf(bp, (sizeof buf - ((bp)-buf)), "%s", login);
      *bp = toupper(*bp);
      bp += strlen(bp);
    } else {
      if (0)
        printf("*bp++=*p\n:");
      if (0)
        printf("bp-buf=%d\n", (bp - buf));
      *bp++ = *p;
    }
  }
  *bp = '\0';
  if (0)
    printf("leaving buildfname\n");
}
```