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Diffstat (limited to 'ubi-utils/src/libubimirror.c')
-rw-r--r--ubi-utils/src/libubimirror.c217
1 files changed, 217 insertions, 0 deletions
diff --git a/ubi-utils/src/libubimirror.c b/ubi-utils/src/libubimirror.c
new file mode 100644
index 0000000..e5715fc
--- /dev/null
+++ b/ubi-utils/src/libubimirror.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, ssize_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, ssize_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, ssize_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;
+}