Add flag to rdsquashfs to optionally set xattrs on unpacked files

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

6 files changed, 59 insertions, 7 deletions

diff --git a/configure.ac b/configure.ac
index e9aa634..19ee8d4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -159,6 +159,8 @@ fi
 ##### additional checks #####
 AX_COMPILE_CHECK_SIZEOF(time_t)
 
+AC_CHECK_HEADERS([sys/xattr.h], [], [])
+
 ##### generate output #####
 
 AC_CONFIG_HEADERS([config.h])
diff --git a/doc/rdsquashfs.1 b/doc/rdsquashfs.1
index ef2a8c6..c6c9330 100644
--- a/doc/rdsquashfs.1
+++ b/doc/rdsquashfs.1
@@ -65,6 +65,10 @@ empty after applying the above rules.
 Do not create sparse files. Always unpack sparse files by
 writing blocks of zeros to disk.
 .TP
+\fB\-\-set\-xattr\fR, \fB\-X\fR
+When unpacking files to disk, set the extended attributes from the
+SquashFS image.
+.TP
 \fB\-\-chmod\fR, \fB\-C\fR
 Change permission flags of unpacked files to
 those store in the SquashFS image.
diff --git a/unpack/options.c b/unpack/options.c
index e5e0389..594b610 100644
--- a/unpack/options.c
+++ b/unpack/options.c
@@ -18,6 +18,9 @@ static struct option long_opts[] = {
 	{ "no-slink", no_argument, NULL, 'L' },
 	{ "no-empty-dir", no_argument, NULL, 'E' },
 	{ "no-sparse", no_argument, NULL, 'Z' },
+#ifdef HAVE_SYS_XATTR_H
+	{ "set-xattr", no_argument, NULL, 'X' },
+#endif
 	{ "jobs", required_argument, NULL, 'j' },
 	{ "describe", no_argument, NULL, 'd' },
 	{ "chmod", no_argument, NULL, 'C' },
@@ -27,7 +30,12 @@ static struct option long_opts[] = {
 	{ "version", no_argument, NULL, 'V' },
 };
 
-static const char *short_opts = "l:c:u:p:x:DSFLCOEZj:dqhV";
+static const char *short_opts =
+	"l:c:u:p:x:DSFLCOEZj:dqhV"
+#ifdef HAVE_SYS_XATTR_H
+	"X"
+#endif
+	;
 
 static const char *help_string =
 "Usage: %s [OPTIONS] <squashfs-file>\n"
@@ -59,6 +67,10 @@ static const char *help_string =
 "                            empty after applying the above rules.\n"
 "  --no-sparse, -Z           Do not create sparse files, always write zero\n"
 "                            blocks to disk.\n"
+#ifdef HAVE_SYS_XATTR_H
+"  --set-xattr, -X           When unpacking files to disk, set the extended\n"
+"                            attributes from the squashfs image.\n"
+#endif
 "  --jobs, -j <count>        Number of parallel unpacking jobs to start.\n"
 "  --chmod, -C               Change permission flags of unpacked files to\n"
 "                            those store in the squashfs image.\n"
@@ -135,6 +147,12 @@ void process_command_line(options_t *opt, int argc, char **argv)
 		case 'Z':
 			opt->flags |= UNPACK_NO_SPARSE;
 			break;
+#ifdef HAVE_SYS_XATTR_H
+		case 'X':
+			opt->flags |= UNPACK_SET_XATTR;
+			opt->rdtree_flags |= RDTREE_READ_XATTR;
+			break;
+#endif
 		case 'j':
 			for (j = 0; optarg[j] != '\0'; ++j) {
 				if (j > 6 || !isdigit(optarg[j]))
diff --git a/unpack/rdsquashfs.c b/unpack/rdsquashfs.c
index 5eb10f2..2162cc4 100644
--- a/unpack/rdsquashfs.c
+++ b/unpack/rdsquashfs.c
@@ -112,7 +112,7 @@ int main(int argc, char **argv)
 		if (fill_unpacked_files(&fs, data, opt.flags, opt.num_jobs))
 			goto out_fs;
 
-		if (update_tree_attribs(n, opt.flags))
+		if (update_tree_attribs(&fs, n, opt.flags))
 			goto out_fs;
 
 		if (opt.unpack_root != NULL && popd() != 0)
diff --git a/unpack/rdsquashfs.h b/unpack/rdsquashfs.h
index 5990ab9..44635d8 100644
--- a/unpack/rdsquashfs.h
+++ b/unpack/rdsquashfs.h
@@ -20,6 +20,9 @@
 
 #include <sys/sysmacros.h>
 #include <sys/types.h>
+#ifdef HAVE_SYS_XATTR_H
+#include <sys/xattr.h>
+#endif
 #include <sys/prctl.h>
 #include <sys/wait.h>
 #include <string.h>
@@ -37,6 +40,7 @@ enum UNPACK_FLAGS {
 	UNPACK_CHOWN = 0x02,
 	UNPACK_QUIET = 0x04,
 	UNPACK_NO_SPARSE = 0x08,
+	UNPACK_SET_XATTR = 0x10,
 };
 
 enum {
@@ -62,7 +66,7 @@ void list_files(tree_node_t *node);
 
 int restore_fstree(tree_node_t *root, int flags);
 
-int update_tree_attribs(tree_node_t *root, int flags);
+int update_tree_attribs(fstree_t *fs, tree_node_t *root, int flags);
 
 int fill_unpacked_files(fstree_t *fs, data_reader_t *data, int flags,
 			unsigned int num_jobs);
diff --git a/unpack/restore_fstree.c b/unpack/restore_fstree.c
index c25763c..7fe074e 100644
--- a/unpack/restore_fstree.c
+++ b/unpack/restore_fstree.c
@@ -91,7 +91,7 @@ static int create_node(tree_node_t *n, int flags)
 	return 0;
 }
 
-static int set_attribs(tree_node_t *n, int flags)
+static int set_attribs(fstree_t *fs, tree_node_t *n, int flags)
 {
 	tree_node_t *c;
 
@@ -100,7 +100,7 @@ static int set_attribs(tree_node_t *n, int flags)
 			return -1;
 
 		for (c = n->data.dir->children; c != NULL; c = c->next) {
-			if (set_attribs(c, flags))
+			if (set_attribs(fs, c, flags))
 				return -1;
 		}
 
@@ -125,6 +125,30 @@ static int set_attribs(tree_node_t *n, int flags)
 			return -1;
 		}
 	}
+#ifdef HAVE_SYS_XATTR_H
+	if ((flags & UNPACK_SET_XATTR) && n->xattr != NULL) {
+		size_t i, len, kidx, vidx;
+		const char *key, *value;
+
+		for (i = 0; i < n->xattr->num_attr; ++i) {
+			kidx = n->xattr->attr[i].key_index;
+			vidx = n->xattr->attr[i].value_index;
+
+			key = str_table_get_string(&fs->xattr_keys, kidx);
+			value = str_table_get_string(&fs->xattr_values, vidx);
+			len = strlen(value);
+
+			if (lsetxattr(n->name, key, value, len, 0)) {
+				fprintf(stderr,
+					"setting xattr '%s' on %s: %s\n",
+					key, n->name, strerror(errno));
+				return -1;
+			}
+		}
+	}
+#else
+	(void)fs;
+#endif
 	return 0;
 }
 
@@ -150,10 +174,10 @@ int restore_fstree(tree_node_t *root, int flags)
 	return 0;
 }
 
-int update_tree_attribs(tree_node_t *root, int flags)
+int update_tree_attribs(fstree_t *fs, tree_node_t *root, int flags)
 {
 	if ((flags & (UNPACK_CHOWN | UNPACK_CHMOD)) == 0)
 		return 0;
 
-	return set_attribs(root, flags);
+	return set_attribs(fs, root, flags);
 }