On Mon, Aug 07, 2023 at 06:51:35PM +0000, Derrick Stolee via GitGitGadget wrote:
> diff --git a/builtin/gc.c b/builtin/gc.c
> index f3942188a61..66a972bc292 100644
> --- a/builtin/gc.c
> +++ b/builtin/gc.c
> @@ -1708,6 +1708,23 @@ static int get_schedule_cmd(const char **cmd, int *is_available)
> return 1;
> }
>
> +MAYBE_UNUSED
> +static int get_random_minute(void)
> +{
> + static int random_initialized = 0;
> +
> + /* Use a static value when under tests. */
> + if (!getenv("GIT_TEST_MAINTENANCE_SCHEDULER"))
> + return 13;
> +
> + if (!random_initialized) {
> + srand((unsigned int)getpid());
> + random_initialized = 1;
> + }
I was wondering where else we call srand() within Git, and it looks like
the only other spot is in `lock_file_timeout()`.
I doubt it, but is there a chance that that code depends on only calling
srand() once? I think the answer is "no", since we only use rand()
within that function to generate a random-ish backoff period, so I think
the repeatability of it doesn't matter all that much.
So I think this is kind of outside the scope of your series, but I
wonder if we should have a git_rand() that automatically initializes the
PRNG with the value of getpid()? Then multiple callers can grab random
values at will without reinitializing the PRNG.
Thanks,
Taylor
