bsd-user: Implement freebsd11 getdirents related syscalls

Implement the freebsd11 variant of the following syscalls:
getdirentries(2)

Co-authored-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Michal Meloun <mmel@FreeBSD.org>
Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>

bsd-user/freebsd/os-stat.h

@@ -41,6 +41,11 @@ __sym_compat(statfs, freebsd11_statfs, FBSD_1.0);
 int freebsd11_fstatfs(int fd, struct freebsd11_statfs *buf);
 __sym_compat(fstatfs, freebsd11_fstatfs, FBSD_1.0);
 
+ssize_t freebsd11_getdirentries(int fd, char *buf, size_t nbytes, off_t *basep);
+__sym_compat(getdirentries, freebsd11_getdirentries, FBSD_1.0);
+ssize_t freebsd11_getdents(int fd, char *buf, size_t nbytes);
+__sym_compat(getdents, freebsd11_getdents, FBSD_1.0);
+
 
 /* stat(2) */
 static inline abi_long do_freebsd11_stat(abi_long arg1, abi_long arg2)
@@ -468,6 +473,45 @@ static inline abi_long do_freebsd11_getdents(abi_long arg1,
     return ret;
 }
 
+/* getdirecentries(2) */
+static inline abi_long do_freebsd11_getdirentries(abi_long arg1,
+        abi_ulong arg2, abi_long nbytes, abi_ulong arg4)
+{
+    abi_long ret;
+    struct freebsd11_dirent *dirp;
+    long basep;
+
+    dirp = lock_user(VERIFY_WRITE, arg2, nbytes, 0);
+    if (dirp == NULL) {
+        return -TARGET_EFAULT;
+    }
+    ret = get_errno(freebsd11_getdirentries(arg1, (char *)dirp, nbytes, &basep));
+    if (!is_error(ret)) {
+        struct freebsd11_dirent *de;
+        int len = ret;
+        int reclen;
+
+        de = dirp;
+        while (len > 0) {
+            reclen = de->d_reclen;
+            if (reclen > len) {
+                return -TARGET_EFAULT;
+            }
+            de->d_reclen = tswap16(reclen);
+            de->d_fileno = tswap32(de->d_fileno);
+            len -= reclen;
+            de = (struct freebsd11_dirent *)((void *)de + reclen);
+        }
+    }
+    unlock_user(dirp, arg2, ret);
+    if (arg4) {
+        if (put_user(basep, arg4, abi_ulong)) {
+            return -TARGET_EFAULT;
+        }
+    }
+    return ret;
+}
+
 /* getdirecentries(2) */
 static inline abi_long do_freebsd_getdirentries(abi_long arg1,
         abi_ulong arg2, abi_long nbytes, abi_ulong arg4)