@@ -223,6 +223,7 @@ tests := \
tst-freopen64-3 \
tst-fseek \
tst-fwrite \
+ tst-fwrite-memstrm \
tst-getline \
tst-getline-enomem \
tst-gets \
new file mode 100644
@@ -0,0 +1,177 @@
+/* Test fwrite on a memory stream.
+ 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/temp_file.h>
+#include <support/xstdio.h>
+#include <support/xunistd.h>
+
+void
+test_ro (void)
+{
+ FILE *f;
+ char *out;
+
+ /* Try to allocate a small buffer for this test. */
+ out = malloc(2);
+ TEST_VERIFY_EXIT (out != NULL);
+
+ /* Try to open the allocated buffer as a read-only stream. */
+ f = fmemopen (out, 2, "r");
+ TEST_VERIFY_EXIT (f != NULL);
+
+ /* Try to write to the temporary file with nmemb = 0, then check that
+ fwrite returns 0. No errors are expected from this. */
+ TEST_COMPARE (fwrite ("a", 1, 0, f), 0);
+ TEST_COMPARE (ferror (f), 0);
+
+ /* Try to write to the temporary file with size = 0, then check that
+ fwrite returns 0. No errors are expected from this. */
+ TEST_COMPARE (fwrite ("a", 0, 1, f), 0);
+ TEST_COMPARE (ferror (f), 0);
+
+ /* Try to write a single byte to the temporary file, then check that
+ fwrite returns 0. Check if an error was reported. */
+ TEST_COMPARE (fwrite ("a", 1, 1, f), 0);
+ TEST_COMPARE (ferror (f), 1);
+
+ clearerr (f);
+ xfclose (f);
+ free (out);
+}
+
+/* Length of the output buffer in bytes. */
+#define RWBUF_SIZE 16 * 1024
+/* Maximum number of bytes to be written in output buffer. The rest will be
+ used to check against overflow. */
+#define RWBUF_SIZE_WRITABLE RWBUF_SIZE-2048
+
+/* Use the following byte to identify areas that should have not been
+ modified. */
+#define KNOWN_BYTE 0xaa
+
+void
+test_one_rw (const char *in, size_t size, size_t nmemb,
+ size_t expected_ret)
+{
+ FILE *f;
+ char *out, *expected_out;
+ /* Total number of bytes expected to be written. */
+ size_t expected_bytes = size * nmemb;
+
+ printf("Testing with size = %zd, nmemb = %zd\n", size, nmemb);
+
+ TEST_VERIFY_EXIT (expected_ret <= RWBUF_SIZE_WRITABLE);
+ TEST_VERIFY_EXIT (expected_bytes <= RWBUF_SIZE_WRITABLE);
+
+ /* Try to allocate a buffer for this test and initialize it with
+ known contents. */
+ out = malloc(RWBUF_SIZE);
+ TEST_VERIFY_EXIT (out != NULL);
+ memset (out, KNOWN_BYTE, RWBUF_SIZE);
+
+ /* Try to allocate a buffer and fill it with the contents that are expected
+ to be in memory after flushing/closing the memory stream. */
+ expected_out = malloc(RWBUF_SIZE);
+ TEST_VERIFY_EXIT (expected_out != NULL);
+ if (expected_bytes > 0)
+ {
+ memcpy (expected_out, in, expected_bytes);
+ expected_out[expected_bytes] = 0;
+ memset (expected_out + expected_bytes + 1, KNOWN_BYTE,
+ RWBUF_SIZE - expected_bytes - 1);
+ }
+ else
+ {
+ /* No changes to the output are expected. */
+ memset (expected_out, KNOWN_BYTE, RWBUF_SIZE);
+ }
+
+ /* Try to open the allocated buffer as a read-write stream. */
+ f = fmemopen (out, RWBUF_SIZE, "w");
+ TEST_VERIFY_EXIT (f != NULL);
+
+ /* Try to write to the memory stream. Check if fwrite() returns the
+ expected value. No errors are expected. */
+ TEST_COMPARE (fwrite (in, size, nmemb, f), expected_ret);
+ TEST_COMPARE (ferror (f), 0);
+
+ xfclose (f);
+
+ /* Ensure the output has the expected contents. */
+ TEST_COMPARE (memcmp (out, expected_out, expected_bytes), 0);
+
+ free (expected_out);
+ free (out);
+}
+
+void
+test_rw (void)
+{
+ char * in;
+ int i, j;
+ size_t size[] = {1, 8, 11, 16, 17, 0};
+ size_t nmemb[] = {32, 83, 278, 709, 4097, RWBUF_SIZE / 2,
+ RWBUF_SIZE_WRITABLE, 0};
+ size_t n;
+
+ /* Try to write to the temporary file with nmemb = 0, then check that
+ fwrite returns 0; */
+ test_one_rw ("a", 1, 0, 0);
+
+ /* Try to write to the temporary file with size = 0, then check that
+ fwrite returns 0; */
+ test_one_rw ("a", 0, 1, 0);
+
+ /* Try to write a single byte to the temporary file, then check that
+ fwrite returns 1; */
+ test_one_rw ("a", 1, 2, 2);
+
+ in = malloc(RWBUF_SIZE);
+ TEST_VERIFY_EXIT (in != NULL);
+ for (i = 0; i < RWBUF_SIZE / 2; i++)
+ in[i] = i % 0xff;
+
+ /* Test with all posibilities of size[] x nmemb[]. */
+ for (i = 0; nmemb[i] != 0; i++)
+ {
+ for (j = 0; size[j] != 0; j++)
+ {
+ n = nmemb[i] / size[j];
+ test_one_rw (in, size[j], n, n);
+ }
+ /* Run the test with a single item of maximum size. */
+ test_one_rw (in, nmemb[i], 1, 1);
+ }
+
+ free (in);
+}
+
+static int
+do_test (void)
+{
+ test_ro ();
+ test_rw ();
+
+ return 0;
+}
+
+#include <support/test-driver.c>