Add no-pad option to gensquashfs, sqfs2tar

This works similar to the option for mksquashfs, preventing the image
from being padded to device block size.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

6 files changed, 29 insertions, 3 deletions

diff --git a/bin/gensquashfs/gensquashfs.1 b/bin/gensquashfs/gensquashfs.1
index 88f58c4..48489a9 100644
--- a/bin/gensquashfs/gensquashfs.1
+++ b/bin/gensquashfs/gensquashfs.1
@@ -106,6 +106,10 @@ Generate an export table for NFS support.
 Do not perform tail end packing on files that are larger than the specified
 block size.
 .TP
+\fB\-\-no\-pad\fR
+Do not pad the resulting image to device block size. May result in an image
+that cannot be loop mounted.
+.TP
 \fB\-\-force\fR, \fB\-f\fR
 Overwrite the output file if it exists.
 .TP
diff --git a/bin/gensquashfs/options.c b/bin/gensquashfs/options.c
index f263bce..9bc79a6 100644
--- a/bin/gensquashfs/options.c
+++ b/bin/gensquashfs/options.c
@@ -8,10 +8,12 @@
 
 enum {
 	ALL_ROOT_OPTION = 1,
+	NO_PAD_OPTION = 2,
 };
 
 static struct option long_opts[] = {
 	{ "all-root", no_argument, NULL, ALL_ROOT_OPTION },
+	{ "no-pad", no_argument, NULL, NO_PAD_OPTION },
 	{ "set-uid", required_argument, NULL, 'u' },
 	{ "set-gid", required_argument, NULL, 'g' },
 	{ "compressor", required_argument, NULL, 'c' },
@@ -123,6 +125,7 @@ const char *extra_options =
 "  --exportable, -e            Generate an export table for NFS support.\n"
 "  --no-tail-packing, -T       Do not perform tail end packing on files that\n"
 "                              are larger than block size.\n"
+"  --no-pad                    Do not pad image to device block size.\n"
 "  --force, -f                 Overwrite the output file if it exists.\n"
 "  --quiet, -q                 Do not print out progress reports.\n"
 "  --help, -h                  Print help text and exit.\n"
@@ -212,6 +215,9 @@ void process_command_line(options_t *opt, int argc, char **argv)
 			opt->force_uid = true;
 			opt->force_gid = true;
 			break;
+		case NO_PAD_OPTION:
+			opt->cfg.no_pad = true;
+			break;
 		case 'u':
 			opt->force_uid_value = strtol(optarg, NULL, 0);
 			opt->force_uid = true;
diff --git a/bin/tar2sqfs/options.c b/bin/tar2sqfs/options.c
index dd0d02f..21e5004 100644
--- a/bin/tar2sqfs/options.c
+++ b/bin/tar2sqfs/options.c
@@ -6,7 +6,12 @@
  */
 #include "tar2sqfs.h"
 
+enum {
+	NO_PAD_OPTION = 1,
+};
+
 static struct option long_opts[] = {
+	{ "no-pad", no_argument, NULL, NO_PAD_OPTION },
 	{ "root-becomes", required_argument, NULL, 'r' },
 	{ "compressor", required_argument, NULL, 'c' },
 	{ "block-size", required_argument, NULL, 'b' },
@@ -81,6 +86,7 @@ static const char *usagestr =
 "  --no-tail-packing, -T       Do not perform tail end packing on files that\n"
 "                              are larger than block size.\n"
 "  --exclude-dir, -E <glob>    Skip tar entry if glob matches.\n"
+"  --no-pad                    Do not pad image to device block size.\n"
 "  --force, -f                 Overwrite the output file if it exists.\n"
 "  --quiet, -q                 Do not print out progress reports.\n"
 "  --help, -h                  Print help text and exit.\n"
@@ -132,6 +138,9 @@ void process_args(int argc, char **argv)
 			break;
 
 		switch (i) {
+		case NO_PAD_OPTION:
+			cfg.no_pad = true;
+			break;
 		case 'S':
 			no_symlink_retarget = true;
 			break;
diff --git a/bin/tar2sqfs/tar2sqfs.1 b/bin/tar2sqfs/tar2sqfs.1
index 2cac9e2..b11b159 100644
--- a/bin/tar2sqfs/tar2sqfs.1
+++ b/bin/tar2sqfs/tar2sqfs.1
@@ -109,6 +109,10 @@ Generate an export table for NFS support.
 Do not perform tail end packing on files that are larger than the
 specified block size.
 .TP
+\fB\-\-no\-pad\fR
+Do not pad the resulting image to device block size. May result in an image
+that cannot be loop mounted.
+.TP
 \fB\-\-force\fR, \fB\-f\fR
 Overwrite the output file if it exists.
 .TP
diff --git a/include/simple_writer.h b/include/simple_writer.h
index 4885b9f..c6d2833 100644
--- a/include/simple_writer.h
+++ b/include/simple_writer.h
@@ -54,6 +54,7 @@ typedef struct {
 	bool exportable;
 	bool no_xattr;
 	bool quiet;
+	bool no_pad;
 } sqfs_writer_cfg_t;
 
 #ifdef __cplusplus
diff --git a/lib/common/writer/finish.c b/lib/common/writer/finish.c
index c539579..bd1e11e 100644
--- a/lib/common/writer/finish.c
+++ b/lib/common/writer/finish.c
@@ -164,9 +164,11 @@ int sqfs_writer_finish(sqfs_writer_t *sqfs, const sqfs_writer_cfg_t *cfg)
 		return -1;
 	}
 
-	if (padd_sqfs(sqfs->outfile, sqfs->super.bytes_used,
-		      cfg->devblksize)) {
-		return -1;
+	if (!cfg->no_pad) {
+		if (padd_sqfs(sqfs->outfile, sqfs->super.bytes_used,
+			      cfg->devblksize)) {
+			return -1;
+		}
 	}
 
 	if (!cfg->quiet)