1. copy_range should be a simple wrapper for copy_file_range(2) and nothing else. and there's already -t option for truncate. so here we remove the truncate action in copy_range. see: https://patchwork.kernel.org/comment/22863587/#1 2. improve the default length value generation: if -l option is omitted use the length that from src_offset to end (src_file's size - src_offset) instead. if src_offset is greater than file size, length is 0. 3. update manpage and have confirmed that this change will not affect xfstests. Signed-off-by: Jianhong Yin <yin-jianhong@xxxxxxx> --- io/copy_file_range.c | 22 +++++----------------- man/man8/xfs_io.8 | 9 +++------ 2 files changed, 8 insertions(+), 23 deletions(-) diff --git a/io/copy_file_range.c b/io/copy_file_range.c index b7b9fd88..02d50e53 100644 --- a/io/copy_file_range.c +++ b/io/copy_file_range.c @@ -66,21 +66,13 @@ copy_src_filesize(int fd) return st.st_size; } -static int -copy_dst_truncate(void) -{ - int ret = ftruncate(file->fd, 0); - if (ret < 0) - perror("ftruncate"); - return ret; -} - static int copy_range_f(int argc, char **argv) { long long src = 0; long long dst = 0; size_t len = 0; + int len_ommited = 1; int opt; int ret; int fd; @@ -112,6 +104,7 @@ copy_range_f(int argc, char **argv) printf(_("invalid length -- %s\n"), optarg); return 0; } + len_ommited = 0; break; case 'f': src_file_nr = atoi(argv[1]); @@ -137,7 +130,7 @@ copy_range_f(int argc, char **argv) fd = filetable[src_file_nr].fd; } - if (src == 0 && dst == 0 && len == 0) { + if (len_ommited) { off64_t sz; sz = copy_src_filesize(fd); @@ -145,13 +138,8 @@ copy_range_f(int argc, char **argv) ret = 1; goto out; } - len = sz; - - ret = copy_dst_truncate(); - if (ret < 0) { - ret = 1; - goto out; - } + if (sz > src) + len = sz - src; } ret = copy_file_range_cmd(fd, &src, &dst, len); diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 index 6e064bdd..8bfaeeba 100644 --- a/man/man8/xfs_io.8 +++ b/man/man8/xfs_io.8 @@ -669,13 +669,10 @@ The source must be specified either by path or as another open file .RB ( \-f ). If -.I src_file -.IR src_offset , -.IR dst_offset , -and .I length -are omitted the contents of src_file will be copied to the beginning of the -open file, overwriting any data already there. +is omitted will use ( src_size - +.I src_offset +) instead. .RS 1.0i .PD 0 .TP 0.4i -- 2.21.0
