Re: [PATCH] sparse-checkout: allow one-character directories in cone mode
From: Junio C Hamano <hidden>
Date: 2020-02-20 22:46:10
"Derrick Stolee via GitGitGadget" [off-list ref] writes:
From: Derrick Stolee <redacted>
In 9e6d3e64 (sparse-checkout: detect short patterns, 2020-01-24), a
condition on the minimum length of a cone-mode pattern was introduced.
However, this condition was off-by-one.
If we have a directory with a single character, say "b", then the
command
git sparse-checkout set b
will correctly add the pattern "/b/" to the sparse-checkout file. When
this is interpeted in dir.c, the pattern is "/b" with the
PATTERN_FLAG_MUSTBEDIR flag. This string has length two, which satisfies
our inclusive inequality (<= 2).
The reason for this inequality is that we will start to read the pattern
string character-by-character using three char pointers: prev, cur,
next. In particular, next is set to the current pattern plus two. The
mistake was that next will still be a valid pointer when the pattern
length is two, since the string is null-terminated.
Make this inequality strict so these patterns work.
Signed-off-by: Derrick Stolee <redacted>
---
sparse-checkout: allow one-character directories in cone mode
This is based on ds/sparse-add.
I discovered this while taking v2.25.1 and ds/sparse-add into our fork
of Git and testing it with Scalar.
Off-by-one errors are tricky, sometimes.Indeed, and thanks for a quick fix.
quoted hunk
Thanks, -Stolee Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-558%2Fderrickstolee%2Fsparse-short-pattern-v1 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-558/derrickstolee/sparse-short-pattern-v1 Pull-Request: https://github.com/gitgitgadget/git/pull/558 dir.c | 2 +- t/t1091-sparse-checkout-builtin.sh | 12 +++++++++++- 2 files changed, 12 insertions(+), 2 deletions(-)diff --git a/dir.c b/dir.c index 7ac0920b713..a87900d43a2 100644 --- a/dir.c +++ b/dir.c@@ -682,7 +682,7 @@ static void add_pattern_to_hashsets(struct pattern_list *pl, struct path_pattern return; } - if (given->patternlen <= 2 || + if (given->patternlen < 2 || *given->pattern == '*' || strstr(given->pattern, "**")) { /* Not a cone pattern. */diff --git a/t/t1091-sparse-checkout-builtin.sh b/t/t1091-sparse-checkout-builtin.sh index c35cbdef454..b4c9c32a037 100755 --- a/t/t1091-sparse-checkout-builtin.sh +++ b/t/t1091-sparse-checkout-builtin.sh@@ -417,10 +417,20 @@ test_expect_success 'pattern-checks: too short' ' cat >repo/.git/info/sparse-checkout <<-\EOF && /* !/*/ - /a + / EOF check_read_tree_errors repo "a" "disabling cone pattern matching" ' +test_expect_success 'pattern-checks: not too short' ' + cat >repo/.git/info/sparse-checkout <<-\EOF && + /* + !/*/ + /b/ + EOF + git -C repo read-tree -mu HEAD 2>err && + test_must_be_empty err && + check_files repo a +' test_expect_success 'pattern-checks: trailing "*"' ' cat >repo/.git/info/sparse-checkout <<-\EOF &&base-commit: ef07659926f64d70e8cb41025c3d7456eecb962e