From 2d81c48fa7f7679a92c9fe674b53656166ade4f8 Mon Sep 17 00:00:00 2001 From: Stefan Beller Date: Mon, 9 Jan 2017 15:16:50 -0800 Subject: pathspec: give better message for submodule related pathspec error Every once in a while someone complains to the mailing list to have run into this weird assertion[1]. The usual response from the mailing list is link to old discussions[2], and acknowledging the problem stating it is known. This patch accomplishes two things: 1. Switch assert() to die("BUG") to give a more readable message. 2. Take one of the cases where we hit a BUG and turn it into a normal "there was something wrong with the input" message. This assertion triggered for cases where there wasn't a programming bug, but just bogus input. In particular, if the user asks for a pathspec that is inside a submodule, we shouldn't assert() or die("BUG"); we should tell the user their request is bogus. The only reason we did not check for it, is the expensive nature of such a check, so callers avoid setting the flag PATHSPEC_STRIP_SUBMODULE_SLASH_EXPENSIVE. However when we die due to bogus input, the expense of CPU cycles spent outweighs the user wondering what went wrong, so run that check unconditionally before dying with a more generic error message. Note: There is a case (e.g. "git -C submodule add .") in which we call strip_submodule_slash_expensive, as git-add requests it via the flag PATHSPEC_STRIP_SUBMODULE_SLASH_EXPENSIVE, but the assert used to trigger nevertheless, because the flag PATHSPEC_LITERAL was not set, such that we executed if (item->nowildcard_len < prefixlen) item->nowildcard_len = prefixlen; and prefixlen was not adapted (e.g. it was computed from "submodule/") So in the die_inside_submodule_path function we also need handle paths, that were stripped before, i.e. are the exact submodule path. This is why the conditions in die_inside_submodule_path are slightly different than in strip_submodule_slash_expensive. [1] https://www.google.com/search?q=item-%3Enowildcard_len [2] http://git.661346.n2.nabble.com/assert-failed-in-submodule-edge-case-td7628687.html https://www.spinics.net/lists/git/msg249473.html Helped-by: Jeff King Helped-by: Junio C Hamano Signed-off-by: Stefan Beller Signed-off-by: Junio C Hamano --- pathspec.c | 35 +++++++++++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) (limited to 'pathspec.c') diff --git a/pathspec.c b/pathspec.c index ff2509ddd1..7ababb3159 100644 --- a/pathspec.c +++ b/pathspec.c @@ -296,6 +296,27 @@ static void strip_submodule_slash_expensive(struct pathspec_item *item) } } +static void die_inside_submodule_path(struct pathspec_item *item) +{ + int i; + + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce = active_cache[i]; + int ce_len = ce_namelen(ce); + + if (!S_ISGITLINK(ce->ce_mode)) + continue; + + if (item->len < ce_len || + !(item->match[ce_len] == '/' || item->match[ce_len] == '\0') || + memcmp(ce->name, item->match, ce_len)) + continue; + + die(_("Pathspec '%s' is in submodule '%.*s'"), + item->original, ce_len, ce->name); + } +} + /* * Perform the initialization of a pathspec_item based on a pathspec element. */ @@ -391,8 +412,18 @@ static void init_pathspec_item(struct pathspec_item *item, unsigned flags, } /* sanity checks, pathspec matchers assume these are sane */ - assert(item->nowildcard_len <= item->len && - item->prefix <= item->len); + if (item->nowildcard_len > item->len || + item->prefix > item->len) { + /* + * This case can be triggered by the user pointing us to a + * pathspec inside a submodule, which is an input error. + * Detect that here and complain, but fallback in the + * non-submodule case to a BUG, as we have no idea what + * would trigger that. + */ + die_inside_submodule_path(item); + die ("BUG: item->nowildcard_len > item->len || item->prefix > item->len)"); + } } static int pathspec_item_cmp(const void *a_, const void *b_) -- cgit v1.2.3