1 files changed, 217 insertions, 0 deletions
diff --git a/ubi-utils/src/libubimirror/ubimirror.c b/ubi-utils/src/libubimirror/ubimirror.c
new file mode 100644
index 0000000..bf6b37c
--- /dev/null
+++ b/ubi-utils/src/libubimirror/ubimirror.c
@@ -0,0 +1,217 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <memory.h>
+#include <fcntl.h>
+
+#include <libubi.h>
+#include "ubimirror.h"
+
+#define COMPARE_BUF_SIZE    (128 * 1024)
+
+#define EBUF(fmt...) do {			\
+	snprintf(err_buf, err_buf_size, fmt);	\
+} while (0)
+
+enum {
+	compare_error = -1,
+	seek_error = -2,
+	write_error = -3,
+	read_error = -4,
+	update_error = -5,
+	ubi_error = -6,
+	open_error = -7,
+	close_error = -8,
+	compare_equal = 0,
+	compare_different = 1
+};
+
+/*
+ * Read len number of bytes from fd.
+ * Return 0 on EOF, -1 on error.
+ */
+static ssize_t fill_buffer(int fd, unsigned char *buf, size_t len)
+{
+	ssize_t got, have = 0;
+
+	do {
+		got = read(fd, buf + have, len - have);
+		if( got == -1 && errno != EINTR )
+			return -1;
+		have += got;
+	} while ( got > 0 && have < len);
+	return have;
+}
+
+/*
+ * Write len number of bytes to fd.
+ * Return bytes written (>= 0), -1 on error.
+ */
+static ssize_t flush_buffer(int fd, unsigned char *buf, size_t len)
+{
+	ssize_t done, have = 0;
+
+	do {
+		done = write(fd, buf + have, len - have);
+		if( done == -1 && errno != EINTR )
+			return -1;
+		have += done;
+	} while ( done > 0 && have < len);
+	return have;
+}
+
+/*
+ *  Compare two files.  Return 0, 1, or -1, depending on whether the
+ *  files are equal, different, or an error occured.
+ *  Return compare-different when target volume can not be read. Might be
+ *  an interrupted volume update and then the target device returns -EIO but
+ *  can be updated.
+ *
+ *  fd_a is source
+ *  fd_b is destination
+ */
+static int
+compare_files(int fd_a, int fd_b)
+{
+	unsigned char buf_a[COMPARE_BUF_SIZE], buf_b[COMPARE_BUF_SIZE];
+	ssize_t len_a, len_b;
+	int rc;
+
+	for (;;) {
+		len_a = fill_buffer(fd_a, buf_a, sizeof(buf_a));
+		if (len_a == -1){
+			rc = compare_error;
+			break;
+		}
+		len_b = fill_buffer(fd_b, buf_b, sizeof(buf_b));
+		if (len_b == -1){
+			rc = compare_different;
+			break;
+		}
+		if( len_a != len_b ){
+			rc = compare_different;
+			break;
+		}
+		if( len_a == 0 ){	/* Size on both filies equal and EOF */
+			rc = compare_equal;
+			break;
+		}
+		if( memcmp(buf_a, buf_b, len_a) != 0 ){
+			rc = compare_different;
+			break;
+		}
+	}
+	/* Position both files at the beginning */
+	if( lseek(fd_a, 0, SEEK_SET) == -1 ||
+	    lseek(fd_b, 0, SEEK_SET) == -1 )
+		rc = seek_error;
+	return rc;
+}
+
+static int
+copy_files(int fd_in, int fd_out)
+{
+	unsigned char buf_a[COMPARE_BUF_SIZE];
+	ssize_t len_a, len_b;
+	unsigned long long update_size, copied;
+
+	if( ubi_vol_get_used_bytes(fd_in, &update_size) == -1 ||
+	    ubi_vol_update(fd_out, update_size) == -1 )
+		return update_error;
+	for( copied = 0; copied < update_size; copied += len_b ){
+		len_a = fill_buffer(fd_in, buf_a, sizeof(buf_a));
+		if (len_a == -1)
+			return read_error;
+		if (len_a == 0)		/* Reach EOF */
+			return 0;
+		len_b = flush_buffer(fd_out, buf_a, len_a);
+		if( len_b != len_a )
+			return write_error;
+	}
+	return 0;
+}
+
+int
+ubimirror(uint32_t devno, int seqnum, uint32_t *ids, size_t ids_size,
+	  char *err_buf, size_t err_buf_size)
+{
+	int rc = 0;
+	uint32_t src_id;
+	ubi_lib_t ulib = NULL;
+	int fd_in = -1, i = 0, fd_out = -1;
+
+	if (ids_size == 0)
+		return 0;
+	else {
+		if ((seqnum < 0) || (seqnum > (ids_size - 1))) {
+			EBUF("volume id %d out of range", seqnum);
+			return EUBIMIRROR_NO_SRC;
+		}
+		src_id = ids[seqnum];
+	}
+
+	rc = ubi_open(&ulib);
+	if (rc != 0)
+		return ubi_error;
+
+	fd_in = ubi_vol_open(ulib, devno, src_id, O_RDONLY);
+	if (fd_in == -1){
+		EBUF("open error source volume %d", ids[i]);
+		rc = open_error;
+		goto err;
+	}
+
+	for (i = 0; i < ids_size; i++) {
+		if (ids[i] == src_id)		/* skip self-mirror */
+			continue;
+
+		fd_out = ubi_vol_open(ulib, devno, ids[i], O_RDWR);
+		if (fd_out == -1){
+			EBUF("open error destination volume %d", ids[i]);
+			rc = open_error;
+			goto err;
+		}
+		rc = compare_files(fd_in, fd_out);
+		if (rc < 0 ){
+			EBUF("compare error volume %d and %d", src_id, ids[i]);
+			goto err;
+		}
+		rc = copy_files(fd_in, fd_out);
+		if (rc != 0) {
+			EBUF("mirror error volume %d to %d", src_id, ids[i]);
+			goto err;
+		}
+		if( (rc = ubi_vol_close(fd_out)) == -1 ){
+			EBUF("close error volume %d", ids[i]);
+			rc = close_error;
+			goto err;
+		}else
+			fd_out = -1;
+	}
+err:
+	if (ulib != NULL)
+		ubi_close(&ulib);
+	if (fd_in != -1)
+		ubi_vol_close(fd_in);
+	if (fd_out != -1)
+		ubi_vol_close(fd_out);
+	return rc;
+}