X-Git-Url: https://git.sven.stormbind.net/?p=sven%2Ffuse-exfat.git;a=blobdiff_plain;f=mkfs%2Ffat.c;fp=mkfs%2Ffat.c;h=c5174a7a748d2fa721facabbf2dde2c1723fff2d;hp=0000000000000000000000000000000000000000;hb=1e7534bbaa34e6c2a8c9809dfcf6588112cbdee4;hpb=65b0f9fc39c546369f4f0f43f36891f7709b891a

diff --git a/mkfs/fat.c b/mkfs/fat.c
new file mode 100644
index 0000000..c5174a7
--- /dev/null
+++ b/mkfs/fat.c
@@ -0,0 +1,88 @@
+/*
+	fat.c (09.11.10)
+	File Allocation Table creation code.
+
+	Free exFAT implementation.
+	Copyright (C) 2011-2018  Andrew Nayenko
+
+	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, either version 2 of the License, or
+	(at your option) any later version.
+
+	This program 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 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.,
+	51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "fat.h"
+#include "cbm.h"
+#include "uct.h"
+#include "rootdir.h"
+#include <unistd.h>
+
+static off_t fat_alignment(void)
+{
+	return (off_t) 128 * get_sector_size();
+}
+
+static off_t fat_size(void)
+{
+	return get_volume_size() / get_cluster_size() * sizeof(cluster_t);
+}
+
+static cluster_t fat_write_entry(struct exfat_dev* dev, cluster_t cluster,
+		cluster_t value)
+{
+	le32_t fat_entry = cpu_to_le32(value);
+	if (exfat_write(dev, &fat_entry, sizeof(fat_entry)) < 0)
+	{
+		exfat_error("failed to write FAT entry 0x%x", value);
+		return 0;
+	}
+	return cluster + 1;
+}
+
+static cluster_t fat_write_entries(struct exfat_dev* dev, cluster_t cluster,
+		uint64_t length)
+{
+	cluster_t end = cluster + DIV_ROUND_UP(length, get_cluster_size());
+
+	while (cluster < end - 1)
+	{
+		cluster = fat_write_entry(dev, cluster, cluster + 1);
+		if (cluster == 0)
+			return 0;
+	}
+	return fat_write_entry(dev, cluster, EXFAT_CLUSTER_END);
+}
+
+static int fat_write(struct exfat_dev* dev)
+{
+	cluster_t c = 0;
+
+	if (!(c = fat_write_entry(dev, c, 0xfffffff8))) /* media type */
+		return 1;
+	if (!(c = fat_write_entry(dev, c, 0xffffffff))) /* some weird constant */
+		return 1;
+	if (!(c = fat_write_entries(dev, c, cbm.get_size())))
+		return 1;
+	if (!(c = fat_write_entries(dev, c, uct.get_size())))
+		return 1;
+	if (!(c = fat_write_entries(dev, c, rootdir.get_size())))
+		return 1;
+
+	return 0;
+}
+
+const struct fs_object fat =
+{
+	.get_alignment = fat_alignment,
+	.get_size = fat_size,
+	.write = fat_write,
+};