user: Please show me the C implementation that matches the assembly code listed below:

```asm
<main>:
  endbr64
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x8,%rsp
  cmp    $0x1,%edi
  jle    L167
  mov    %rsi,%rbp
  mov    $0x0,%eax
  call   <setsid@plt>
  cmp    $0xffffffff,%eax
  je     L77
L177:
  mov    $0x0,%eax
  call   <getpid@plt>
  mov    %eax,%ebx
  mov    $0x0,%eax
  call   <getpgrp@plt>
  mov    %eax,%r12d
  mov    $0x0,%edi
  call   <getsid@plt>
  mov    %eax,%esi
  mov    %r12d,%ecx
  mov    %ebx,%edx
  lea    D51(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  call   <fork@plt>
  test   %eax,%eax
  js     L60
  jne    L181
  call   <setsid@plt>
  cmp    $0xffffffff,%eax
  je     L190
L160:
  mov    $0x0,%eax
  call   <getpid@plt>
  mov    %eax,%ebx
  mov    $0x0,%eax
  call   <getpgrp@plt>
  mov    %eax,%r12d
  mov    $0x0,%edi
  call   <getsid@plt>
  mov    %eax,%esi
  mov    %r12d,%ecx
  mov    %ebx,%edx
  lea    D92(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
L6:
  call   <fork@plt>
  mov    %eax,%ebx
  test   %eax,%eax
  js     L106
  je     L178
L189:
  mov    %ebx,%esi
  mov    %ebx,%edi
  call   <setpgid@plt>
  cmp    $0xffffffff,%eax
  je     L159
L166:
  mov    %ebx,%esi
  mov    $0x0,%edi
  call   <setpgid@plt>
  cmp    $0xffffffff,%eax
  je     L41
L85:
  mov    $0x0,%eax
  call   <print@plt>
  mov    $0x0,%eax
L86:
  add    $0x8,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  ret
L167:
  lea    D1(%rip),%rdi
  call   <puts@plt>
  mov    $0xffffffff,%eax
  jmp    L86
L77:
  lea    D49(%rip),%rdi
  call   <perror@plt>
  jmp    L177
L60:
  lea    D97(%rip),%rdi
  call   <err_sys@plt>
  jmp    L6
L190:
  lea    D49(%rip),%rdi
  call   <err_sys@plt>
  jmp    L160
L181:
  mov    $0x0,%edi
  call   <exit@plt>
  jmp    L6
L106:
  lea    D97(%rip),%rdi
  call   <err_sys@plt>
  jmp    L189
L178:
  mov    $0x0,%eax
  call   <getpid@plt>
  mov    %eax,%r12d
  mov    $0x0,%eax
  call   <getpgrp@plt>
  mov    %eax,%r13d
  mov    $0x0,%edi
  call   <getsid@plt>
  mov    %eax,%esi
  mov    %r13d,%ecx
  mov    %r12d,%edx
  lea    D74(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    $0x0,%esi
  mov    $0x0,%edi
  call   <setpgid@plt>
  cmp    $0xffffffff,%eax
  je     L84
L102:
  mov    0x8(%rbp),%rdi
  mov    $0x0,%edx
  mov    %rdi,%rsi
  call   <execlp@plt>
  mov    $0xffffffff,%edi
  call   <exit@plt>
  jmp    L189
L84:
  lea    D71(%rip),%rdi
  call   <err_sys@plt>
  jmp    L102
L159:
  lea    D38(%rip),%rdi
  call   <err_sys@plt>
  jmp    L166
L41:
  lea    D94(%rip),%rdi
  call   <err_sys@plt>
  jmp    L85
```

tool_calls: name: read_data
arguments: data_tag: D51
data_type: string
name: read_data
arguments: data_tag: D92
data_type: string
name: read_data
arguments: data_tag: D1
data_type: string
name: read_data
arguments: data_tag: D49
data_type: string
name: read_data
arguments: data_tag: D97
data_type: string
name: read_data
arguments: data_tag: D74
data_type: string
name: read_data
arguments: data_tag: D71
data_type: string
name: read_data
arguments: data_tag: D38
data_type: string
name: read_data
arguments: data_tag: D94
data_type: string

tool: D51: parent %u: %u, %u


tool: D92: session %u: %u, %u


tool: D1: Usage: session grpid

tool: D49: setsid

tool: D97: fork

tool: D74: child %u: %u, %u


tool: D71: setpgid child

tool: D38: setpgid 1

tool: D94: setpgid 2

assistant: ```c
int main(int argc, char *argv[]) {
  if (argc < 2) {
    printf("Usage: session grpid\n");
    return -1;
  }
  if (setsid() == -1)
    perror("setsid");
  int ret = 0;
  pid_t pid = getpid();
  pid_t grp = getpgrp();
  pid_t sid = getsid(0);
  printf("parent %u: %u, %u\n", sid, pid, grp);
  pid_t cid = fork();
  if (cid < 0)
    err_sys("fork");
  else if (cid == 0) {
    if (setsid() == -1)
      err_sys("setsid");
    pid = getpid();
    grp = getpgrp();
    sid = getsid(0);
    printf("session %u: %u, %u\n", sid, pid, grp);
  } else
    exit(0);
  cid = fork();
  if (cid < 0)
    err_sys("fork");
  else if (cid == 0) {
    pid_t pid = getpid();
    pid_t grp = getpgrp();
    pid_t sid = getsid(0);
    printf("child %u: %u, %u\n", sid, pid, grp);
    ret = setpgid(0, 0);
    if (ret == -1)
      err_sys("setpgid child");
    execlp(argv[1], argv[1], NULL);
    exit(-1);
  }
  ret = setpgid(cid, cid);
  if (ret == -1)
    err_sys("setpgid 1");
  ret = setpgid(0, cid);
  if (ret == -1)
    err_sys("setpgid 2");
  print();
  return 0;
}
```