Add fallocate.c to contrib from Eric Sandeen

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 152 insertions, 0 deletions

diff --git a/contrib/fallocate.c b/contrib/fallocate.c
new file mode 100644
index 00000000..23684f3d
--- /dev/null
+++ b/contrib/fallocate.c
@@ -0,0 +1,152 @@
+/*
+ * fallocate - utility to use the fallocate system call
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All rights reserved.
+ * Written by Eric Sandeen <sandeen@redhat.com>
+ *
+ * cvtnum routine taken from xfsprogs,
+ * Copyright (c) 2003-2005 Silicon Graphics, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#define _GNU_SOURCE
+#define _LARGEFILE_SOURCE
+#define _LARGEFILE64_SOURCE
+
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ctype.h>
+
+// #include <linux/falloc.h>
+#define FALLOC_FL_KEEP_SIZE	0x01
+
+void usage(void)
+{
+	printf("Usage: fallocate [-n] [-o offset] -l length filename\n");
+	exit(EXIT_FAILURE);
+}
+
+#define EXABYTES(x)     ((long long)(x) << 60)
+#define PETABYTES(x)    ((long long)(x) << 50)
+#define TERABYTES(x)    ((long long)(x) << 40)
+#define GIGABYTES(x)    ((long long)(x) << 30)
+#define MEGABYTES(x)    ((long long)(x) << 20)
+#define KILOBYTES(x)    ((long long)(x) << 10)
+
+long long
+cvtnum(char *s)
+{
+	long long	i;
+	char		*sp;
+	int		c;
+
+	i = strtoll(s, &sp, 0);
+	if (i == 0 && sp == s)
+		return -1LL;
+	if (*sp == '\0')
+		return i;
+	if (sp[1] != '\0')
+		return -1LL;
+
+	c = tolower(*sp);
+	switch (c) {
+	case 'k':
+		return KILOBYTES(i);
+	case 'm':
+		return MEGABYTES(i);
+	case 'g':
+		return GIGABYTES(i);
+	case 't':
+		return TERABYTES(i);
+	case 'p':
+		return PETABYTES(i);
+	case 'e':
+		return  EXABYTES(i);
+	}
+
+	return -1LL;
+}
+
+int main(int argc, char **argv)
+{
+	int	fd;
+	char	*fname;
+	int	opt;
+	loff_t	length = -2LL;
+	loff_t	offset = 0;
+	int	falloc_mode = 0;
+	int	error;
+
+	while ((opt = getopt(argc, argv, "nl:o:")) != -1) {
+		switch(opt) {
+		case 'n':
+			/* do not change filesize */
+			falloc_mode = FALLOC_FL_KEEP_SIZE;
+			break;
+		case 'l':
+			length = cvtnum(optarg);
+			break;
+		case 'o':
+			offset = cvtnum(optarg);
+			break;
+		default:
+			usage();
+		}
+	}
+
+	if (length == -2LL) {
+		printf("Error: no length argument specified\n");
+		usage();
+	}
+
+	if (length <= 0) {
+		printf("Error: invalid length value specified\n");
+		usage();
+	}
+
+	if (offset < 0) {
+		printf("Error: invalid offset value specified\n");
+		usage();
+	}
+
+	if (optind == argc) {
+		printf("Error: no filename specified\n");
+		usage();
+	}
+
+	fname = argv[optind++];
+
+	/* Should we create the file if it doesn't already exist? */
+	fd = open(fname, O_WRONLY|O_DIRECTORY);
+	if (fd < 0) {
+		perror("Error opening file");
+		exit(EXIT_FAILURE);
+	}
+
+	error = syscall(SYS_fallocate, fd, falloc_mode, offset, length);
+
+	if (error < 0) {
+		perror("fallocate failed");
+		exit(EXIT_FAILURE);
+	}
+
+	close(fd);
+	return 0;
+}