On Mon, Aug 08, 2022 at 08:35:21AM +0000, Li Linchao via GitGitGadget wrote:
> The '--disk-usage' option for git-rev-list was introduced in 16950f8384
> (rev-list: add --disk-usage option for calculating disk usage, 2021-02-09).
> This is very useful for people inspect their git repo's objects usage
> infomation, but the resulting number is quit hard for a human to read.
>
> Teach git rev-list to output a human readable result when using
> '--disk-usage'.
OK. When adding --disk-usage, I never really dreamed people would use it
for human output, since "du .git" is usually a suitable approximation. :)
But I don't have any real objection. I'm curious what your use case is
like, if you don't mind sharing. We used it at GitHub for computing
per-fork sizes for analysis, etc (so the result was always fed into
another script).
> Documentation/rev-list-options.txt | 5 +++-
> builtin/rev-list.c | 42 ++++++++++++++++++++++++------
> t/t6115-rev-list-du.sh | 22 ++++++++++++++++
> 3 files changed, 60 insertions(+), 9 deletions(-)
The patch itself looks pretty sensible (and thanks Ævar for the first
round of review; the suggestions there all looked good). A few small
comments:
> @@ -481,8 +485,13 @@ static int try_bitmap_disk_usage(struct rev_info *revs,
> if (!bitmap_git)
> return -1;
>
> - printf("%"PRIuMAX"\n",
> - (uintmax_t)get_disk_usage_from_bitmap(bitmap_git, revs));
> + size_from_bitmap = get_disk_usage_from_bitmap(bitmap_git, revs);
> + if (human_readable)
> + strbuf_humanise_bytes(&disk_buf, size_from_bitmap);
> + else
> + strbuf_addf(&disk_buf, "%"PRIuMAX"", (uintmax_t)size_from_bitmap);
> + puts(disk_buf.buf);
> + strbuf_release(&disk_buf);
It's not a lot of duplicated lines, but since it is implementing policy
logic, I think it would be nice to move the formatting decision into a
function. Something like:
static void show_disk_usage(off_t size)
{
struct strbuf sb = STRBUF_INIT;
if (human_readable)
strbuf_humanise_bytes(&sb, size);
else
strbuf_addf(&sb, "%"PRIuMAX, (uintmax_t)size_from_bitmap);
puts(sb.buf);
strbuf_release(&sb);
}
and then you can call it from here, and from the non-bitmap path below.
(Also, while typing it out, I noticed that you don't need the extra ""
after PRIuMAX; that just concatenates an empty string).
> - if (!strcmp(arg, "--disk-usage")) {
> - show_disk_usage = 1;
> - info.flags |= REV_LIST_QUIET;
> - continue;
> + if (skip_prefix(arg, "--disk-usage", &arg)) {
> + if (*arg == '=') {
> + if (!strcmp(++arg, "human")) {
> + human_readable = 1;
> + show_disk_usage = 1;
> + info.flags |= REV_LIST_QUIET;
> + continue;
> + } else
> + die(_("invalid value for '%s': '%s', try --disk-usage=human"), "--disk-usage", arg);
> + } else {
> + show_disk_usage = 1;
> + info.flags |= REV_LIST_QUIET;
> + continue;
> + }
> }
We can put the common parts of each side of the conditional into the
outer block to avoid repeating ourselves. Also, your code matches
--show-disk-usage-without-an-equals, since it nows uses skip_prefix().
You could fix that by checking for '\0' in *arg. So together, something
like:
if (skip_prefix(arg, "--disk-usage", &arg)) {
if (*arg == '=') {
if (!strcmp(++arg, "human"))
human_readable = 1;
else
die(...);
} else if (*arg) {
/*
* Arguably should goto a label to continue chain of ifs?
* Doesn't matter unless we try to add --disk-usage-foo
* afterwards
*/
usage(rev_list_usage);
}
show_disk_usage = 1;
info.flags |= REV_LIST_QUIET;
continue;
}
-Peff
