Ever since 862e730ec1 (commit-slab: introduce slabname##_peek() function, 2015-05-14) the slabname##_peek() function is documented as: This function is similar to indegree_at(), but it will return NULL until a call to indegree_at() was made for the commit. This, however, is usually not the case. If indegree_at() allocates memory, then it will do so not only for the single commit it got as parameter, but it will allocate a whole new, ~512kB slab. Later on, if any other commit's 'index' field happens to point into an already allocated slab, then indegree_peek() for such a commit will return a valid non-NULL pointer, pointing to a zero-initialized location in the slab, even if no indegree_at() call has been made for that commit yet. Update slabname##_peek()'s documentation to clarify this. Signed-off-by: SZEDER Gábor <szeder.dev@xxxxxxxxx> --- commit-slab.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/commit-slab.h b/commit-slab.h index 69bf0c807c..05b3f2804e 100644 --- a/commit-slab.h +++ b/commit-slab.h @@ -24,7 +24,12 @@ * - int *indegree_peek(struct indegree *, struct commit *); * * This function is similar to indegree_at(), but it will return NULL - * until a call to indegree_at() was made for the commit. + * if the location to store the data associated with the given commit + * has not been allocated yet. + * Note that the location to store the data might have already been + * allocated even if no indegree_at() call has been made for that commit + * yet; in this case this function returns a pointer to a + * zero-initialized location. * * - void init_indegree(struct indegree *); * void init_indegree_with_stride(struct indegree *, int); -- 2.26.0.rc0.366.gb2d359bb99
