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

[Jaegeuk Kim <jaegeuk@kernel.org>]

On 02/15, Daeho Jeong wrote:
> 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"					\

Can we also have all the other options as well?

> +"  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
>