| Message ID | patch-2.4-d88b2c0410-20210617T105537Z-avarab@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | pack-objects: use revision.c's --stdin parsing | expand |
On Thu, Jun 17, 2021 at 12:57:35PM +0200, Ævar Arnfjörð Bjarmason wrote: > > In 8b3dce56508 (Teach --stdin option to "log" family, 2009-11-03) we > added the "disable_stdin" flag, and then much later in > a12cbe23ef7 (rev-list: make empty --stdin not an error, 2018-08-22) we > gained a "read_from_stdin" flag. > > The interaction between these is more subtle than they might appear at > first sight, as noted in a12cbe23ef7. "read_stdin" is not the inverse > of "disable_stdin", rather we read stdin if we see the "--stdin" > option. > > The "read" is intended to understood as "I read it", not "you should > read it". Let's avoid this confusion by using "consume" and "consumed" > instead, i.e. a word whose present and past tense isn't the same. Unfortunately, I still find your disambiguation text to be ambiguous... > diff --git a/revision.c b/revision.c > index 8140561b6c..69b3812093 100644 > --- a/revision.c > +++ b/revision.c > @@ -2741,11 +2741,11 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s > } > > if (!strcmp(arg, "--stdin")) { > - if (revs->disable_stdin) { > + if (revs->stdin_handling == REV_INFO_STDIN_IGNORE) { > argv[left++] = arg; > continue; > } > - if (revs->read_from_stdin++) > + if (revs->consumed_stdin_per_option++) > die("--stdin given twice?"); > read_revisions_from_stdin(revs, &prune_data); > continue; Eeh. I know this is not logic introduced by your patch, BUT your patch does change the semantics of the replacement to ->disable_stdin from a bool to an enum. There is an implicit assumption here - "if stdin_handling isn't REV_INFO_STDIN_IGNORE, then it must be REV_INFO_CONSUME_ON_OPTION." That's true during this patch, but becomes false in the next patch in this series, and it didn't look to me like this section of code was changed accordingly. [snip] > + /* > + * Did we read from stdin due to stdin_handling == > + * REV_INFO_STDIN_CONSUME_ON_OPTION and seeing the --stdin > + * option? > */ > - int read_from_stdin; > + int consumed_stdin_per_option; And indeed, the comment here confirms the implicit assumption made in the code. Based on this comment, I'd expect the implementation to explicitly check that stdin_handling == CONSUME_ON_OPTION. - Emily
About the subject: > revision.h: unify "disable_stdin" and "read_from_stdin" Hmm...there is no unification, I think? Both of these remain distinct - it's just that both were renamed and one was changed into an enum. > @@ -114,9 +119,22 @@ struct rev_info { > int rev_input_given; > > /* > - * Whether we read from stdin due to the --stdin option. > + * How should we handle seeing --stdin? > + * > + * Defaults to reading if we see it with > + * REV_INFO_STDIN_CONSUME_ON_OPTION. > + * > + * Can be set to REV_INFO_STDIN_IGNORE to ignore any provided > + * --stdin option. > + */ > + enum rev_info_stdin stdin_handling; This was changed to an enum, because (looking at the next patches) we want to add an entry to it. Maybe mention it here - at the very least, this will help reviewers check that the addition of extra entries to the enum in future commits will not negatively affect functionality introduced in this commit. > + /* > + * Did we read from stdin due to stdin_handling == > + * REV_INFO_STDIN_CONSUME_ON_OPTION and seeing the --stdin > + * option? > */ > - int read_from_stdin; > + int consumed_stdin_per_option; The usage of "per" here seems correct to me, but it's not the first meaning that springs to mind. Could this just be called "consumed_stdin"?
diff --git a/builtin/am.c b/builtin/am.c index 0b2d886c81..3a6c8455b4 100644 --- a/builtin/am.c +++ b/builtin/am.c @@ -1355,7 +1355,7 @@ static void write_commit_patch(const struct am_state *state, struct commit *comm repo_init_revisions(the_repository, &rev_info, NULL); rev_info.diff = 1; rev_info.abbrev = 0; - rev_info.disable_stdin = 1; + rev_info.stdin_handling = REV_INFO_STDIN_IGNORE; rev_info.show_root_diff = 1; rev_info.diffopt.output_format = DIFF_FORMAT_PATCH; rev_info.no_commit_id = 1; @@ -1390,7 +1390,7 @@ static void write_index_patch(const struct am_state *state) fp = xfopen(am_path(state, "patch"), "w"); repo_init_revisions(the_repository, &rev_info, NULL); rev_info.diff = 1; - rev_info.disable_stdin = 1; + rev_info.stdin_handling = REV_INFO_STDIN_IGNORE; rev_info.no_commit_id = 1; rev_info.diffopt.output_format = DIFF_FORMAT_PATCH; rev_info.diffopt.use_color = 0; diff --git a/builtin/blame.c b/builtin/blame.c index 641523ff9a..c9f66c58c4 100644 --- a/builtin/blame.c +++ b/builtin/blame.c @@ -1061,7 +1061,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix) argv[argc - 1] = "--"; } - revs.disable_stdin = 1; + revs.stdin_handling = REV_INFO_STDIN_IGNORE; setup_revisions(argc, argv, &revs, NULL); if (!revs.pending.nr && is_bare_repository()) { struct commit *head_commit; diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c index f33d30d57b..fc548ebe16 100644 --- a/builtin/diff-tree.c +++ b/builtin/diff-tree.c @@ -122,7 +122,7 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix) die(_("index file corrupt")); opt->abbrev = 0; opt->diff = 1; - opt->disable_stdin = 1; + opt->stdin_handling = REV_INFO_STDIN_IGNORE; memset(&s_r_opt, 0, sizeof(s_r_opt)); s_r_opt.tweak = diff_tree_tweak_rev; diff --git a/builtin/rev-list.c b/builtin/rev-list.c index 7677b1af5a..88bd9ef954 100644 --- a/builtin/rev-list.c +++ b/builtin/rev-list.c @@ -651,7 +651,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) if ((!revs.commits && reflog_walk_empty(revs.reflog_info) && (!(revs.tag_objects || revs.tree_objects || revs.blob_objects) && !revs.pending.nr) && - !revs.rev_input_given && !revs.read_from_stdin) || + !revs.rev_input_given && !revs.consumed_stdin_per_option) || revs.diff) usage(rev_list_usage); diff --git a/revision.c b/revision.c index 8140561b6c..69b3812093 100644 --- a/revision.c +++ b/revision.c @@ -2741,11 +2741,11 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s } if (!strcmp(arg, "--stdin")) { - if (revs->disable_stdin) { + if (revs->stdin_handling == REV_INFO_STDIN_IGNORE) { argv[left++] = arg; continue; } - if (revs->read_from_stdin++) + if (revs->consumed_stdin_per_option++) die("--stdin given twice?"); read_revisions_from_stdin(revs, &prune_data); continue; diff --git a/revision.h b/revision.h index 17698cb51a..475c8ed785 100644 --- a/revision.h +++ b/revision.h @@ -86,6 +86,11 @@ struct rev_cmdline_info { struct oidset; struct topo_walk_info; +enum rev_info_stdin { + REV_INFO_STDIN_CONSUME_ON_OPTION = 0, + REV_INFO_STDIN_IGNORE, +}; + struct rev_info { /* Starting list */ struct commit_list *commits; @@ -114,9 +119,22 @@ struct rev_info { int rev_input_given; /* - * Whether we read from stdin due to the --stdin option. + * How should we handle seeing --stdin? + * + * Defaults to reading if we see it with + * REV_INFO_STDIN_CONSUME_ON_OPTION. + * + * Can be set to REV_INFO_STDIN_IGNORE to ignore any provided + * --stdin option. + */ + enum rev_info_stdin stdin_handling; + + /* + * Did we read from stdin due to stdin_handling == + * REV_INFO_STDIN_CONSUME_ON_OPTION and seeing the --stdin + * option? */ - int read_from_stdin; + int consumed_stdin_per_option; /* topo-sort */ enum rev_sort_order sort_order; @@ -216,7 +234,6 @@ struct rev_info { date_mode_explicit:1, preserve_subject:1, encode_email_headers:1; - unsigned int disable_stdin:1; /* --show-linear-break */ unsigned int track_linear:1, track_first_time:1, diff --git a/sequencer.c b/sequencer.c index 0bec01cf38..4e73bd79d6 100644 --- a/sequencer.c +++ b/sequencer.c @@ -3377,7 +3377,7 @@ static int make_patch(struct repository *r, log_tree_opt.abbrev = 0; log_tree_opt.diff = 1; log_tree_opt.diffopt.output_format = DIFF_FORMAT_PATCH; - log_tree_opt.disable_stdin = 1; + log_tree_opt.stdin_handling = REV_INFO_STDIN_IGNORE; log_tree_opt.no_commit_id = 1; log_tree_opt.diffopt.file = fopen(buf.buf, "w"); log_tree_opt.diffopt.use_color = GIT_COLOR_NEVER; @@ -4513,7 +4513,7 @@ static int pick_commits(struct repository *r, log_tree_opt.diff = 1; log_tree_opt.diffopt.output_format = DIFF_FORMAT_DIFFSTAT; - log_tree_opt.disable_stdin = 1; + log_tree_opt.stdin_handling = REV_INFO_STDIN_IGNORE; if (read_oneliner(&buf, rebase_path_orig_head(), 0) && !get_oid(buf.buf, &orig) &&
In 8b3dce56508 (Teach --stdin option to "log" family, 2009-11-03) we added the "disable_stdin" flag, and then much later in a12cbe23ef7 (rev-list: make empty --stdin not an error, 2018-08-22) we gained a "read_from_stdin" flag. The interaction between these is more subtle than they might appear at first sight, as noted in a12cbe23ef7. "read_stdin" is not the inverse of "disable_stdin", rather we read stdin if we see the "--stdin" option. The "read" is intended to understood as "I read it", not "you should read it". Let's avoid this confusion by using "consume" and "consumed" instead, i.e. a word whose present and past tense isn't the same. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- builtin/am.c | 4 ++-- builtin/blame.c | 2 +- builtin/diff-tree.c | 2 +- builtin/rev-list.c | 2 +- revision.c | 4 ++-- revision.h | 23 ++++++++++++++++++++--- sequencer.c | 4 ++-- 7 files changed, 29 insertions(+), 12 deletions(-)