[PATCH] f2fs_io: add lseek command to execute lseek()

[Daeho Jeong <daeho43@gmail.com>]

From: Daeho Jeong <daehojeong@google.com>

Added lseek command to support lseek() for SEEK_DATA and SEEK_HOLE.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
---
 tools/f2fs_io/f2fs_io.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/tools/f2fs_io/f2fs_io.c b/tools/f2fs_io/f2fs_io.c
index e7d286a..b5c5b97 100644
--- a/tools/f2fs_io/f2fs_io.c
+++ b/tools/f2fs_io/f2fs_io.c
@@ -1630,6 +1630,43 @@ static void do_removexattr(int argc, char **argv, const struct cmd_desc *cmd)
 	exit(0);
 }
 
+#define lseek_desc "do lseek for SEEK_DATA or SEEK_HOLE for a file"
+#define lseek_help					\
+"f2fs_io lseek [whence] [offset] [file_path]\n\n"	\
+"Do lseek file data in file_path\n"			\
+"whence can be\n"					\
+"  data     : SEEK_DATA, return the file offset to the next data location from offset\n"\
+"  hole     : SEEK_HOLE, return the file offset to the next hole from offset\n"
+
+static void do_lseek(int argc, char **argv, const struct cmd_desc *cmd)
+{
+	int fd, whence;
+	off_t offset, ret;
+
+	if (argc != 4) {
+		fputs("Excess arguments\n\n", stderr);
+		fputs(cmd->cmd_help, stderr);
+		exit(1);
+	}
+
+	offset = atoi(argv[2]);
+
+	if (!strcmp(argv[1], "data"))
+		whence = SEEK_DATA;
+	else if (!strcmp(argv[1], "hole"))
+		whence = SEEK_HOLE;
+	else
+		die("Wrong whence type");
+
+	fd = xopen(argv[3], O_RDONLY, 0);
+
+	ret = lseek(fd, offset, whence);
+	if (ret < 0)
+		die_errno("lseek failed");
+	printf("returned offset=%ld\n", ret);
+	exit(0);
+}
+
 #define CMD_HIDDEN 	0x0001
 #define CMD(name) { #name, do_##name, name##_desc, name##_help, 0 }
 #define _CMD(name) { #name, do_##name, NULL, NULL, CMD_HIDDEN }
@@ -1671,6 +1708,7 @@ const struct cmd_desc cmd_list[] = {
 	CMD(listxattr),
 	CMD(setxattr),
 	CMD(removexattr),
+	CMD(lseek),
 	{ NULL, NULL, NULL, NULL, 0 }
 };
 
-- 
2.43.0.687.g38aa6559b0-goog