"Derrick Stolee via GitGitGadget" <gitgitgad...@gmail.com> writes:
> From: Derrick Stolee <dsto...@microsoft.com>
>
> The write_commit_graph() method uses die() to report failure and
> exit when confronted with an unexpected condition. This use of
> die() in a library function is incorrect and is now replaced by
> error() statements and an int return type.
OK.
> diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
> index 537fdfd0f0..2e86251f02 100644
> --- a/builtin/commit-graph.c
> +++ b/builtin/commit-graph.c
> @@ -141,6 +141,7 @@ static int graph_write(int argc, const char **argv)
> struct string_list *pack_indexes = NULL;
> struct string_list *commit_hex = NULL;
> struct string_list lines;
> + int result;
>
> static struct option builtin_commit_graph_write_options[] = {
> OPT_STRING(0, "object-dir", &opts.obj_dir,
> @@ -168,10 +169,8 @@ static int graph_write(int argc, const char **argv)
>
> read_replace_refs = 0;
>
> - if (opts.reachable) {
> - write_commit_graph_reachable(opts.obj_dir, opts.append, 1);
> - return 0;
> - }
> + if (opts.reachable)
> + return write_commit_graph_reachable(opts.obj_dir, opts.append,
> 1);
>
> string_list_init(&lines, 0);
> if (opts.stdin_packs || opts.stdin_commits) {
> @@ -188,14 +187,14 @@ static int graph_write(int argc, const char **argv)
> UNLEAK(buf);
> }
>
> - write_commit_graph(opts.obj_dir,
> - pack_indexes,
> - commit_hex,
> - opts.append,
> - 1);
> + result = write_commit_graph(opts.obj_dir,
> + pack_indexes,
> + commit_hex,
> + opts.append,
> + 1);
>
> UNLEAK(lines);
> - return 0;
> + return result;
> }
What were the error values this function used to return? I am
wondering if the callers of this function are prepraed to see the
returned values from write_commit_graph() this function stores in
'result' (which presumably are small negative value like our usual
internal API convention)?
> diff --git a/builtin/commit.c b/builtin/commit.c
> index 2986553d5f..b9ea7222fa 100644
> --- a/builtin/commit.c
> +++ b/builtin/commit.c
> @@ -1669,8 +1669,9 @@ int cmd_commit(int argc, const char **argv, const char
> *prefix)
> "new_index file. Check that disk is not full and quota
> is\n"
> "not exceeded, and then \"git reset HEAD\" to recover."));
>
> - if (git_env_bool(GIT_TEST_COMMIT_GRAPH, 0))
> - write_commit_graph_reachable(get_object_directory(), 0, 0);
> + if (git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
> + write_commit_graph_reachable(get_object_directory(), 0, 0))
> + return 1;
This is good. An error signalled as a small negative integer would
not seep thru to the exit status but is explicitly turned into 1
with this change.
> + if (gc_write_commit_graph &&
> + write_commit_graph_reachable(get_object_directory(), 0,
> + !quiet && !daemonized))
> + return 1;
Ditto.
> +int write_commit_graph_reachable(const char *obj_dir, int append,
> + int report_progress)
> {
> struct string_list list = STRING_LIST_INIT_DUP;
> + int result;
>
> for_each_ref(add_ref_to_list, &list);
> - write_commit_graph(obj_dir, NULL, &list, append, report_progress);
> + result = write_commit_graph(obj_dir, NULL, &list,
> + append, report_progress);
>
> string_list_clear(&list, 0);
> + return result;
> }
OK. The callers of write_commit_graph_reachable() can be careful
about its return values to the same degree as the callers of
write_commit_graph().
These functions perhaps deserves
/*
* returns X when ....
*/
in front (or in *.h)?
> +int write_commit_graph(const char *obj_dir,
> + struct string_list *pack_indexes,
> + struct string_list *commit_hex,
> + int append, int report_progress)
> {
> struct packed_oid_list oids;
> struct packed_commit_list commits;
> struct hashfile *f;
> uint32_t i, count_distinct = 0;
> - char *graph_name;
> + char *graph_name = NULL;
> struct lock_file lk = LOCK_INIT;
> uint32_t chunk_ids[5];
> uint64_t chunk_offsets[5];
> @@ -883,15 +886,17 @@ void write_commit_graph(const char *obj_dir,
> uint64_t progress_cnt = 0;
> struct strbuf progress_title = STRBUF_INIT;
> unsigned long approx_nr_objects;
> + int res = 0;
>
> if (!commit_graph_compatible(the_repository))
> - return;
> + return 0;
OK. I tend to find "return 0" easier to read/follow than "return
res" here.
> oids.nr = 0;
> approx_nr_objects = approximate_object_count();
> oids.alloc = approx_nr_objects / 32;
> oids.progress = NULL;
> oids.progress_done = 0;
> + commits.list = NULL;
>
> if (append) {
> prepare_commit_graph_one(the_repository, obj_dir);
> @@ -932,10 +937,16 @@ void write_commit_graph(const char *obj_dir,
> strbuf_setlen(&packname, dirlen);
> strbuf_addstr(&packname, pack_indexes->items[i].string);
> p = add_packed_git(packname.buf, packname.len, 1);
> - if (!p)
> - die(_("error adding pack %s"), packname.buf);
> - if (open_pack_index(p))
> - die(_("error opening index for %s"),
> packname.buf);
> + if (!p) {
> + error(_("error adding pack %s"), packname.buf);
> + res = 1;
> + goto cleanup;
> + }
> + if (open_pack_index(p)) {
> + error(_("error opening index for %s"),
> packname.buf);
> + res = 1;
> + goto cleanup;
> + }
Hmph, is this signal an error by returning a positive "1"? That's a
bit unusual.
> @@ -1006,8 +1017,11 @@ void write_commit_graph(const char *obj_dir,
> }
> stop_progress(&progress);
>
> - if (count_distinct >= GRAPH_EDGE_LAST_MASK)
> - die(_("the commit graph format cannot write %d commits"),
> count_distinct);
> + if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
> + error(_("the commit graph format cannot write %d commits"),
> count_distinct);
> + res = 1;
> + goto cleanup;
> + }
>
> commits.nr = 0;
> commits.alloc = count_distinct;
> @@ -1039,16 +1053,21 @@ void write_commit_graph(const char *obj_dir,
> num_chunks = num_extra_edges ? 4 : 3;
> stop_progress(&progress);
>
> - if (commits.nr >= GRAPH_EDGE_LAST_MASK)
> - die(_("too many commits to write graph"));
> + if (commits.nr >= GRAPH_EDGE_LAST_MASK) {
> + error(_("too many commits to write graph"));
> + res = 1;
> + goto cleanup;
> + }
>
> compute_generation_numbers(&commits, report_progress);
>
> graph_name = get_commit_graph_filename(obj_dir);
> if (safe_create_leading_directories(graph_name)) {
> UNLEAK(graph_name);
> - die_errno(_("unable to create leading directories of %s"),
> - graph_name);
> + error(_("unable to create leading directories of %s"),
> + graph_name);
> + res = errno;
> + goto cleanup;
> }
Hmph. Do we know errno==0 means no error everywhere? Do we know
errno==1 is not used by anybody as a meaningful value?
What I am getting at is if a hardcoded "1" we saw above as "error
exists but we are not telling the caller what kind of system-level
error led to it by returning errno" (and a hardcoded "0" as "there
is no error") are consistent with this use of "res" where "the
callers are allowed to learn what system-level error led to this
error return from this function by sending the return value of this
function to strerror() or comparing with EWHATEVER". I do not think
this is a good design.
