@@ -61,6 +61,7 @@ tests := \
tst-closedir-leaks \
tst-fdopendir \
tst-fdopendir2 \
+ tst-readdir-long \
tst-scandir \
tst-scandir64 \
tst-seekdir \
new file mode 100644
@@ -0,0 +1,231 @@
+/* Test readdir (+variants) behavior with file names of varying length.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/fuse.h>
+#include <support/support.h>
+#include <support/xdirent.h>
+#include <support/readdir.h>
+
+/* If positive, at this length an EMSGSIZE error is injected. */
+static int inject_error_at_length;
+
+/* Return a file name, LENGTH bytes long. */
+static char *
+name_of_length (size_t length)
+{
+ char *result = xmalloc (length + 1);
+ unsigned int prefix = snprintf (result, length + 1, "%zu-", length);
+ for (size_t i = prefix; i < length; ++i)
+ result[i] = 'A' + ((length + i) % 26);
+ result[length] = '\0';
+ return result;
+}
+
+/* Add the directory entry at OFFSET to the stream D. */
+static uint64_t
+add_directory_entry (struct support_fuse_dirstream *d, uint64_t offset)
+{
+ unsigned int length = offset + 1;
+ if (length > 1000)
+ /* Longer than what is possible to produce with 256
+ UTF-8-encoded Unicode code points. */
+ return 0;
+
+ char *to_free = NULL;
+ const char *name;
+ uint64_t ino = 1000 + length; /* Arbitrary value, distinct from 1. */
+ uint32_t type = DT_REG;
+ if (offset <= 1)
+ {
+ type = DT_DIR;
+ name = ".." + !offset; /* "." or "..". */
+ ino = 1;
+ }
+ else if (length == 1000)
+ name = "short";
+ else
+ {
+ to_free = name_of_length (length);
+ name = to_free;
+ }
+
+ ++offset;
+ bool added = support_fuse_dirstream_add (d, ino, offset, type, name);
+ free (to_free);
+ if (added)
+ return offset;
+ else
+ return 0;
+}
+
+/* Set to true if getdents64 should produce only one entry. */
+static bool one_entry_per_getdents64;
+
+static void
+fuse_thread (struct support_fuse *f, void *closure)
+{
+ struct fuse_in_header *inh;
+ while ((inh = support_fuse_next (f)) != NULL)
+ {
+ if (support_fuse_handle_mountpoint (f)
+ || (inh->nodeid == 1 && support_fuse_handle_directory (f)))
+ continue;
+ switch (inh->opcode)
+ {
+ case FUSE_READDIR:
+ if (inh->nodeid == 1)
+ {
+ uint64_t offset = support_fuse_cast (READ, inh)->offset;
+ if (inject_error_at_length == offset + 1)
+ support_fuse_reply_error (f, EMSGSIZE);
+ else
+ {
+ struct support_fuse_dirstream *d
+ = support_fuse_prepare_readdir (f);
+ while (true)
+ {
+ offset = add_directory_entry (d, offset);
+ if (offset == 0 || one_entry_per_getdents64
+ /* Error will be reported at next READDIR. */
+ || offset + 1 == inject_error_at_length)
+ break;
+ }
+ support_fuse_reply_prepared (f);
+ }
+ }
+ else
+ support_fuse_reply_error (f, EIO);
+ break;
+ default:
+ FAIL ("unexpected event %s", support_fuse_opcode (inh->opcode));
+ support_fuse_reply_error (f, EIO);
+ }
+ }
+}
+
+/* Run the tests for the specified readdir variant OP. */
+static void
+run_readdir_tests (struct support_fuse *f, enum support_readdir_op op)
+{
+ printf ("info: testing %s (inject_error=%d unbuffered=%d)\n",
+ support_readdir_function (op), inject_error_at_length,
+ (int) one_entry_per_getdents64);
+
+ bool testing_r = support_readdir_r_variant (op);
+
+ DIR *dir = xopendir (support_fuse_mountpoint (f));
+ struct support_dirent e = { 0, };
+ TEST_VERIFY (support_readdir (dir, op, &e));
+ TEST_COMPARE (e.d_ino, 1);
+ TEST_COMPARE_STRING (e.d_name, ".");
+
+ TEST_VERIFY (support_readdir (dir, op, &e));
+ TEST_COMPARE (e.d_ino, 1);
+ TEST_COMPARE_STRING (e.d_name, "..");
+
+ for (unsigned int i = 3; i < 1000; ++i)
+ {
+ if (i == inject_error_at_length)
+ /* Error expected below. */
+ break;
+
+ if (i >= sizeof ((struct dirent) { 0, }.d_name) && testing_r)
+ /* This is a readir_r test. The longer names are not
+ available because they do not fit into struct dirent. */
+ break;
+
+ char *expected_name = name_of_length (i);
+ TEST_COMPARE (strlen (expected_name), i);
+ TEST_VERIFY (support_readdir (dir, op, &e));
+ TEST_COMPARE (e.d_ino, 1000 + i);
+ TEST_COMPARE_STRING (e.d_name, expected_name);
+ free (expected_name);
+ }
+
+ if (inject_error_at_length == 0)
+ {
+ /* Check that the ENAMETOOLONG error does not prevent reading a
+ later short name. */
+ TEST_VERIFY (support_readdir (dir, op, &e));
+ TEST_COMPARE (e.d_ino, 2000);
+ TEST_COMPARE_STRING (e.d_name, "short");
+
+ if (testing_r)
+ /* An earlier name was too long. */
+ support_readdir_expect_error (dir, op, ENAMETOOLONG);
+ else
+ /* Entire directory read without error. */
+ TEST_VERIFY (!support_readdir (dir, op, &e));
+ }
+ else
+ support_readdir_expect_error (dir, op, EMSGSIZE);
+
+ free (e.d_name);
+ xclosedir (dir);
+}
+
+/* Run all readdir variants for both fully-buffered an unbuffered
+ (one-at-a-time) directory streams. */
+static void
+run_fully_buffered_and_singleton_buffers (struct support_fuse *f)
+{
+ for (int do_one_entry = 0; do_one_entry < 2; ++do_one_entry)
+ {
+ one_entry_per_getdents64 = do_one_entry;
+ for (enum support_readdir_op op = 0; op <= support_readdir_op_last();
+ ++op)
+ run_readdir_tests (f, op);
+ }
+}
+
+static int
+do_test (void)
+{
+ /* Smoke test for name_of_length. */
+ {
+ char *name = name_of_length (5);
+ TEST_COMPARE_STRING (name, "5-HIJ");
+ free (name);
+
+ name = name_of_length (6);
+ TEST_COMPARE_STRING (name, "6-IJKL");
+ free (name);
+ }
+
+ support_fuse_init ();
+ struct support_fuse *f = support_fuse_mount (fuse_thread, NULL);
+
+ run_fully_buffered_and_singleton_buffers (f);
+
+ inject_error_at_length = 100;
+ run_fully_buffered_and_singleton_buffers (f);
+
+ inject_error_at_length = 300;
+ run_fully_buffered_and_singleton_buffers (f);
+
+ support_fuse_unmount (f);
+ return 0;
+}
+
+#include <support/test-driver.c>