Add very basic ftruncate() regression test, with a comment rather more

thorough than the tests regarding what should be tested.

2 files changed, 109 insertions, 0 deletions

diff --git a/tools/regression/file/ftruncate/Makefile b/tools/regression/file/ftruncate/Makefile
new file mode 100644
index 0000000..fcb57f5
--- /dev/null
+++ b/tools/regression/file/ftruncate/Makefile
@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+PROG=	ftruncate
+NO_MAN=
+WARNS=	2
+
+.include <bsd.prog.mk>
diff --git a/tools/regression/file/ftruncate/ftruncate.c b/tools/regression/file/ftruncate/ftruncate.c
new file mode 100644
index 0000000..31d7210
--- /dev/null
+++ b/tools/regression/file/ftruncate/ftruncate.c
@@ -0,0 +1,102 @@
+/*-
+ * Copyright (c) 2006 Robert N. M. Watson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Very simple regression test.  Open a temporary file, then proceed to
+ * ftruncate it to various values and check that fstat returns those values.
+ * First we run forwards through a set of sizes starting with zero, then back
+ * again.
+ *
+ * Future tests that might be of interest:
+ *
+ * - Make sure that files grown via ftruncate() return 0 bytes for data
+ *   reads.
+ *
+ * - Make sure that we can't ftruncate on a read-only descriptor.
+ *
+ * - Make sure we get EISDIR on a directory.
+ */
+
+#include <sys/stat.h>
+
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <unistd.h>
+
+/*
+ * Select various potentially interesting sizes at and around power of 2
+ * edges.
+ */
+static off_t sizes[] = {0, 1, 2, 3, 4, 127, 128, 129, 511, 512, 513, 1023,
+    1024, 1025, 2047, 2048, 2049, 4095, 4096, 4097, 8191, 8192, 8193, 16383,
+    16384, 16385};
+static int size_count = sizeof(sizes) / sizeof(off_t);
+
+int
+main(int argc, char *argv[])
+{
+	char path[PATH_MAX];
+	struct stat sb;
+	int fd, i;
+
+	snprintf(path, PATH_MAX, "/tmp/ftruncate.XXXXXXXXXXXXX");
+	fd = mkstemp(path);
+	if (fd < 0)
+		err(-1, "makestemp");
+	(void)unlink(path);
+
+	if (ftruncate(fd, -1) == 0)
+		errx(-1, "ftruncate(fd, -1) succeeded");
+	if (errno != EINVAL)
+		err(-1, "ftruncate(fd, -1) returned wrong error");
+
+	for (i = 0; i < size_count; i++) {
+		if (ftruncate(fd, sizes[i]) < 0)
+			err(-1, "ftruncate(%llu) up", sizes[i]);
+		if (fstat(fd, &sb) < 0)
+			err(-1, "stat");
+		if (sb.st_size != sizes[i])
+			errx(-1, "fstat(%llu) returned %llu up", sizes[i],
+			    sb.st_size);
+	}
+
+	for (i = size_count - 1; i >= 0; i--) {
+		if (ftruncate(fd, sizes[i]) < 0)
+			err(-1, "ftruncate(%llu) down", sizes[i]);
+		if (fstat(fd, &sb) < 0)
+			err(-1, "stat");
+		if (sb.st_size != sizes[i])
+			errx(-1, "fstat(%llu) returned %llu down", sizes[i],
+			    sb.st_size);
+	}
+
+	close(fd);
+	return (0);
+}