bsd-user: Implement pdgetpid(2) and the undocumented setugid.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20230925182425.3163-26-kariem.taha2.7@gmail.com>

bsd-user/freebsd/os-proc.h

@@ -34,6 +34,8 @@ pid_t safe_wait4(pid_t wpid, int *status, int options, struct rusage *rusage);
 pid_t safe_wait6(idtype_t idtype, id_t id, int *status, int options,
     struct __wrusage *wrusage, siginfo_t *infop);
 
+extern int __setugid(int flag);
+
 /* execve(2) */
 static inline abi_long do_freebsd_execve(abi_ulong path_or_fd, abi_ulong argp,
         abi_ulong envp)
@@ -162,4 +164,25 @@ static inline abi_long do_freebsd_getloginclass(abi_ulong arg1, abi_ulong arg2)
     return ret;
 }
 
+/* pdgetpid(2) */
+static inline abi_long do_freebsd_pdgetpid(abi_long fd, abi_ulong target_pidp)
+{
+    abi_long ret;
+    pid_t pid;
+
+    ret = get_errno(pdgetpid(fd, &pid));
+    if (!is_error(ret)) {
+        if (put_user_u32(pid, target_pidp)) {
+            return -TARGET_EFAULT;
+        }
+    }
+    return ret;
+}
+
+/* undocumented __setugid */
+static inline abi_long do_freebsd___setugid(abi_long arg1)
+{
+    return -TARGET_ENOSYS;
+}
+
 #endif /* BSD_USER_FREEBSD_OS_PROC_H */

bsd-user/freebsd/os-syscall.c

@@ -383,6 +383,14 @@ static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
         ret = do_freebsd_getloginclass(arg1, arg2);
         break;
 
+    case TARGET_FREEBSD_NR_pdgetpid: /* pdgetpid(2) */
+        ret = do_freebsd_pdgetpid(arg1, arg2);
+        break;
+
+    case TARGET_FREEBSD_NR___setugid: /* undocumented */
+        ret = do_freebsd___setugid(arg1);
+        break;
+
     case TARGET_FREEBSD_NR_utrace: /* utrace(2) */
         ret = do_bsd_utrace(arg1, arg2);
         break;