[PATCH] show-branch: fix segfault when showbranch.default exists
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jun 9, 2009, 06:26 UTC
- Message-ID
- <7vfxe9udln.fsf@alter.siamese.dyndns.org>
When running "git show-branch" without any parameter in a repository that has showbranch.default defined, we used to rely on the fact that our handcrafted option parsing loop never looked at av[0].
The array of default strings had the first real command line argument in default_arg[0], but the option parser wanted to look at the array starting at av[1], so we assigned the address of -1th element to av to force the loop start working from default_arg[0].
This no longer worked since 5734365 (show-branch: migrate to parse-options API, 2009-05-21), as parse_options_start() saved the incoming &av[0] in its ctx->out and later in parse_options_end() it did memmove to ctx->out (with ctx->cpidx == 0), overwriting the memory before default_arg[] array.
I am not sure if this is a bug in parse_options(), or a bug in the caller, and tonight I do not have enough concentration to figure out which. In any case, this patch works the issue around.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- builtin-show-branch.c | 14 +++++++++++--- 1 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/builtin-show-branch.c b/builtin-show-branch.c index 01bea3b..baec9ed 100644 --- a/builtin-show-branch.c +++ b/builtin-show-branch.c @@ -565,7 +565,15 @@ static int git_show_branch_config(const char *var, const char *value, void *cb) if (!strcmp(var, "showbranch.default")) { if (!value) return config_error_nonbool(var); - if (default_alloc <= default_num + 1) { + /* + * default_arg is now passed to parse_options(), so we need to + * mimick the real argv a bit better. + */ + if (!default_num) { + default_alloc = 20; + default_arg = xcalloc(default_alloc, sizeof(*default_arg)); + default_arg[default_num++] = "show-branch"; + } else if (default_alloc <= default_num + 1) { default_alloc = default_alloc * 3 / 2 + 20; default_arg = xrealloc(default_arg, sizeof *default_arg * default_alloc); } @@ -692,8 +700,8 @@ int cmd_show_branch(int ac, const char **av, const char *prefix) /* If nothing is specified, try the default first */ if (ac == 1 && default_num) { - ac = default_num + 1; - av = default_arg - 1; /* ick; we would not address av[0] */ + ac = default_num; + av = default_arg; } ac = parse_options(ac, av, prefix, builtin_show_branch_options,