1 files changed, 154 insertions, 0 deletions
diff --git a/mkfs.ubifs/compr.c b/mkfs.ubifs/compr.c
new file mode 100644
index 0000000..285354e
--- /dev/null
+++ b/mkfs.ubifs/compr.c
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2008 Nokia Corporation.
+ * Copyright (C) 2008 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * 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 St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy
+ *          Adrian Hunter
+ *          Zoltan Sogor
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <zlib.h>
+#include <lzo/lzo1x.h>
+#include <linux/types.h>
+
+#include "compr.h"
+#include "ubifs-media.h"
+
+static void *lzo_mem;
+static unsigned long long errcnt = 0;
+
+#define DEFLATE_DEF_LEVEL     Z_DEFAULT_COMPRESSION
+#define DEFLATE_DEF_WINBITS   11
+#define DEFLATE_DEF_MEMLEVEL  8
+
+static int zlib_deflate(void *in_buf, size_t in_len, void *out_buf,
+			size_t *out_len)
+{
+	z_stream strm;
+
+	strm.zalloc = NULL;
+	strm.zfree = NULL;
+
+	/*
+	 * Match exactly the zlib parameters used by the linux kernel crypto
+	 * API.
+	 */
+        if (deflateInit2(&strm, DEFLATE_DEF_LEVEL, Z_DEFLATED,
+			 -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
+			 Z_DEFAULT_STRATEGY)) {
+		errcnt += 1;
+		return -1;
+	}
+
+	strm.next_in = in_buf;
+	strm.avail_in = in_len;
+	strm.total_in = 0;
+
+	strm.next_out = out_buf;
+	strm.avail_out = *out_len;
+	strm.total_out = 0;
+
+	if (deflate(&strm, Z_FINISH) != Z_STREAM_END) {
+		deflateEnd(&strm);
+		errcnt += 1;
+		return -1;
+	}
+
+	if (deflateEnd(&strm) != Z_OK) {
+		errcnt += 1;
+		return -1;
+	}
+
+	*out_len = strm.total_out;
+
+	return 0;
+}
+
+static int lzo_compress(void *in_buf, size_t in_len, void *out_buf,
+			size_t *out_len)
+{
+	lzo_uint len;
+	int ret;
+
+	len = *out_len;
+	ret = lzo1x_999_compress(in_buf, in_len, out_buf, &len, lzo_mem);
+	*out_len = len;
+
+	if (ret != LZO_E_OK) {
+		errcnt += 1;
+		return -1;
+	}
+
+	return 0;
+}
+
+static int no_compress(void *in_buf, size_t in_len, void *out_buf,
+		       size_t *out_len)
+{
+	memcpy(out_buf, in_buf, in_len);
+	*out_len = in_len;
+	return 0;
+}
+
+int compress_data(void *in_buf, size_t in_len, void *out_buf, size_t *out_len,
+		  int type)
+{
+	int ret = 1;
+
+	if (in_len < UBIFS_MIN_COMPR_LEN) {
+		no_compress(in_buf, in_len, out_buf, out_len);
+		return MKFS_UBIFS_COMPR_NONE;
+	}
+
+	switch (type) {
+	case MKFS_UBIFS_COMPR_LZO:
+		ret = lzo_compress(in_buf, in_len, out_buf, out_len);
+		break;
+	case MKFS_UBIFS_COMPR_ZLIB:
+		ret = zlib_deflate(in_buf, in_len, out_buf, out_len);
+		break;
+	case MKFS_UBIFS_COMPR_NONE:
+		ret = 1;
+		break;
+	default:
+		errcnt += 1;
+		break;
+	}
+	if (ret || *out_len >= in_len) {
+		no_compress(in_buf, in_len, out_buf, out_len);
+		return MKFS_UBIFS_COMPR_NONE;
+	}
+	return type;
+}
+
+int init_compression(void)
+{
+	lzo_mem = malloc(LZO1X_999_MEM_COMPRESS);
+	if (!lzo_mem)
+		return -1;
+	return 0;
+}
+
+void destroy_compression(void)
+{
+	free(lzo_mem);
+	if (errcnt)
+		fprintf(stderr, "%llu compression errors occurred\n", errcnt);
+}