[PATCH v1 2/5] dump.erofs: add "-s" option to dump superblock information

[Guo Xuenan <guoxuenan@huawei.com>]

Signed-off-by: Guo Xuenan <guoxuenan@huawei.com>
Signed-off-by: mpiglet <mpiglet@outlook.com>
---
 dump/main.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/dump/main.c b/dump/main.c
index 8fbc24a..25ac89f 100644
--- a/dump/main.c
+++ b/dump/main.c
@@ -17,6 +17,12 @@
 #include "erofs/print.h"
 #include "erofs/io.h"
 
+struct dumpcfg {
+	bool print_superblock;
+	bool print_version;
+};
+static struct dumpcfg dumpcfg;
+
 static struct option long_options[] = {
 	{"help", no_argument, 0, 1},
 	{0, 0, 0, 0},
@@ -26,6 +32,7 @@ static void usage(void)
 {
 	fputs("usage: [options] erofs-image \n\n"
 		"Dump erofs layout from erofs-image, and [options] are:\n"
+		"-s          print information about superblock\n"
 		"-v/-V      print dump.erofs version info\n"
 		"-h/--help  display this help and exit\n", stderr);
 }
@@ -41,6 +48,9 @@ static int dumpfs_parse_options_cfg(int argc, char **argv)
 	while ((opt = getopt_long(argc, argv, "sSvVi:I:h",
 					long_options, NULL)) != -1) {
 		switch (opt) {
+		case 's':
+			dumpcfg.print_superblock = true;
+			break;
 		case 'v':
 		case 'V':
 			dumpfs_print_version();
@@ -68,6 +78,39 @@ static int dumpfs_parse_options_cfg(int argc, char **argv)
 	return 0;
 }
 
+static void dumpfs_print_superblock(void)
+{
+	time_t time = sbi.build_time;
+
+	fprintf(stderr, "Filesystem magic number:	0x%04X\n", EROFS_SUPER_MAGIC_V1);
+	fprintf(stderr, "Filesystem blocks: 		%lu\n", sbi.blocks);
+	fprintf(stderr, "Filesystem meta block:		%u\n", sbi.meta_blkaddr);
+	fprintf(stderr, "Filesystem xattr block:	%u\n", sbi.xattr_blkaddr);
+	fprintf(stderr, "Filesystem root nid:		%ld\n", sbi.root_nid);
+	fprintf(stderr, "Filesystem valid inos:		%lu\n", sbi.inos);
+	fprintf(stderr, "Filesystem created:		%s", ctime(&time));
+	fprintf(stderr, "Filesystem uuid:		");
+	for (int i = 0; i < 16; i++)
+		fprintf(stderr, "%02x", sbi.uuid[i]);
+	fprintf(stderr, "\n");
+
+	if (erofs_sb_has_lz4_0padding())
+		fprintf(stderr, "Filesystem support lz4 0padding\n");
+	else
+		fprintf(stderr, "Filesystem not support lz4 0padding\n");
+
+	if (erofs_sb_has_big_pcluster())
+		fprintf(stderr, "Filesystem support big pcluster\n");
+	else
+		fprintf(stderr, "Filesystem not support big pcluster\n");
+
+	if (erofs_sb_has_sb_chksum())
+		fprintf(stderr, "Filesystem has super block checksum feature\n");
+	else
+		fprintf(stderr, "Filesystem has no superblock checksum feature\n");
+
+}
+
 int main(int argc, char **argv)
 {
 	int err = 0;
@@ -80,5 +123,20 @@ int main(int argc, char **argv)
 		return -1;
 	}
 
+	err = dev_open_ro(cfg.c_img_path);
+	if (err) {
+		erofs_err("open image file failed");
+		return -1;
+	}
+
+	err = erofs_read_superblock();
+	if (err) {
+		erofs_err("read superblock failed");
+		return -1;
+	}
+
+	if (dumpcfg.print_superblock)
+		dumpfs_print_superblock();
+
 	return 0;
 }
-- 
2.25.4