Re: [PATCH v2 5/5] fetch: Make --jobs control submodules and remotes

SZEDER Gábor [off-list ref] writes:

On Mon, Aug 12, 2019 at 02:34:48PM -0700, Palmer Dabbelt wrote:

quoted

diff --git a/builtin/fetch.c b/builtin/fetch.c
index 67d001f3f78b..41498e9efb3b 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c

@@ -114,6 +114,20 @@ static int git_fetch_config(const char *k, const char *v, void *cb)
 	return git_default_config(k, v, cb);
 }
 
+static int parse_jobs_arg(const struct option *opt, const char *arg, int unset)
+{
+	int jobs;
+
+	jobs = atoi(arg);
+	if (jobs < 1)
+		die(_("There must be a positive number of jobs"));
+
+	max_children_for_submodules = jobs;
+	max_children_for_fetch = jobs;
+
+	return 0;
+}
+
 static int parse_refmap_arg(const struct option *opt, const char *arg, int unset)
 {
 	BUG_ON_OPT_NEG(unset);

@@ -142,12 +156,13 @@ static struct option builtin_fetch_options[] = {
 		    N_("fetch all tags and associated objects"), TAGS_SET),
 	OPT_SET_INT('n', NULL, &tags,
 		    N_("do not fetch all tags (--no-tags)"), TAGS_UNSET),
-	OPT_INTEGER('j', "jobs", &max_children_for_submodules,
+	{ OPTION_CALLBACK, 'j', "jobs", NULL, N_("jobs"),
+		    N_("number of parallel tasks to run while fetching"),
+		    PARSE_OPT_OPTARG, &parse_jobs_arg },

These changes result segmentation faults in the tests '--quiet
propagates to parallel submodules' and 'fetching submodules respects
parallel settings' in 't5526-fetch-submodules.sh'.

If the number of jobs is specified as '-j 2' or '--jobs 7', i.e. as an
unstuck argument of the option, as opposed to '-j2' or '--jobs=7',
then 'arg' in the parse_jobs_arg() callback is NULL, which then causes
the segfault somewhere inside that atoi() call.

True.  

An easier and more readable way would be to set another "nr-jobs"
variable using plain vanilla OPT_INTEGER() and override the other
two with it when they are not set after parse_options() returns, I
guess.