[PATCH v3 2/9] cache-tree: simplify verify_cache() prototype
From: Derrick Stolee via GitGitGadget <hidden>
Date: 2021-01-23 19:59:35
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Derrick Stolee <redacted> The verify_cache() method takes an array of cache entries and a count, but these are always provided directly from a struct index_state. Use a pointer to the full structure instead. There is a subtle point when istate->cache_nr is zero that subtracting one will underflow. This triggers a failure in t0000-basic.sh, among others. Use "i + 1 < istate->cache_nr" to avoid these strange comparisons. Convert i to be unsigned as well, which also removes the potential signed overflow in the unlikely case that cache_nr is over 2.1 billion entries. The 'funny' variable has a maximum value of 11, so making it unsigned does not change anything of importance. Signed-off-by: Derrick Stolee <redacted> --- cache-tree.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/cache-tree.c b/cache-tree.c
index 60b6aefbf51..acac6d58c37 100644
--- a/cache-tree.c
+++ b/cache-tree.c@@ -151,16 +151,15 @@ void cache_tree_invalidate_path(struct index_state *istate, const char *path) istate->cache_changed |= CACHE_TREE_CHANGED; } -static int verify_cache(struct cache_entry **cache, - int entries, int flags) +static int verify_cache(struct index_state *istate, int flags) { - int i, funny; + unsigned i, funny; int silent = flags & WRITE_TREE_SILENT; /* Verify that the tree is merged */ funny = 0; - for (i = 0; i < entries; i++) { - const struct cache_entry *ce = cache[i]; + for (i = 0; i < istate->cache_nr; i++) { + const struct cache_entry *ce = istate->cache[i]; if (ce_stage(ce)) { if (silent) return -1;
@@ -180,13 +179,13 @@ static int verify_cache(struct cache_entry **cache, * stage 0 entries. */ funny = 0; - for (i = 0; i < entries - 1; i++) { + for (i = 0; i + 1 < istate->cache_nr; i++) { /* path/file always comes after path because of the way * the cache is sorted. Also path can appear only once, * which means conflicting one would immediately follow. */ - const struct cache_entry *this_ce = cache[i]; - const struct cache_entry *next_ce = cache[i + 1]; + const struct cache_entry *this_ce = istate->cache[i]; + const struct cache_entry *next_ce = istate->cache[i + 1]; const char *this_name = this_ce->name; const char *next_name = next_ce->name; int this_len = ce_namelen(this_ce);
@@ -438,7 +437,7 @@ int cache_tree_update(struct index_state *istate, int flags) { int skip, i; - i = verify_cache(istate->cache, istate->cache_nr, flags); + i = verify_cache(istate, flags); if (i) return i;
--
gitgitgadget