@matheusbsbs / matheus-bagliano / commits / 8d87e338e1

cache-tree: simplify verify_cache() prototype

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 <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Derrick Stolee committed Jan 23, 2021 at 19:58 UTC 8d87e338e16e022545638a0e9a3e15c6bdb56111
1 file changed +8 -9
cache-tree.c
+8 -9
@@ -151,16 +151,15 @@ void cache_tree_invalidate_path(struct index_state *istate, const char *path)
151 istate->cache_changed |= CACHE_TREE_CHANGED;
152 }
153
154 -static int verify_cache(struct cache_entry **cache,
155 - int entries, int flags)
154 +static int verify_cache(struct index_state *istate, int flags)
155 {
157 - int i, funny;
156 + unsigned i, funny;
157 int silent = flags & WRITE_TREE_SILENT;
158
159 /* Verify that the tree is merged */
160 funny = 0;
162 - for (i = 0; i < entries; i++) {
163 - const struct cache_entry *ce = cache[i];
161 + for (i = 0; i < istate->cache_nr; i++) {
162 + const struct cache_entry *ce = istate->cache[i];
163 if (ce_stage(ce)) {
164 if (silent)
165 return -1;
@@ -180,13 +179,13 @@ static int verify_cache(struct cache_entry **cache,
179 * stage 0 entries.
180 */
181 funny = 0;
183 - for (i = 0; i < entries - 1; i++) {
182 + for (i = 0; i + 1 < istate->cache_nr; i++) {
183 /* path/file always comes after path because of the way
184 * the cache is sorted. Also path can appear only once,
185 * which means conflicting one would immediately follow.
186 */
188 - const struct cache_entry *this_ce = cache[i];
189 - const struct cache_entry *next_ce = cache[i + 1];
187 + const struct cache_entry *this_ce = istate->cache[i];
188 + const struct cache_entry *next_ce = istate->cache[i + 1];
189 const char *this_name = this_ce->name;
190 const char *next_name = next_ce->name;
191 int this_len = ce_namelen(this_ce);
@@ -438,7 +437,7 @@ int cache_tree_update(struct index_state *istate, int flags)
437 {
438 int skip, i;
439
441 - i = verify_cache(istate->cache, istate->cache_nr, flags);
440 + i = verify_cache(istate, flags);
441
442 if (i)
443 return i;