merge(3p/git): Merge git subtree at v2.29.2

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

third_party/git/hashmap.c

@@ -51,7 +51,7 @@ unsigned int memihash(const void *buf, size_t len)
 }
 
 /*
- * Incoporate another chunk of data into a memihash
+ * Incorporate another chunk of data into a memihash
  * computation.
  */
 unsigned int memihash_cont(unsigned int hash_seed, const void *buf, size_t len)
@@ -140,8 +140,8 @@ static inline struct hashmap_entry **find_entry_ptr(const struct hashmap *map,
 }
 
 static int always_equal(const void *unused_cmp_data,
-			const void *unused1,
-			const void *unused2,
+			const struct hashmap_entry *unused1,
+			const struct hashmap_entry *unused2,
 			const void *unused_keydata)
 {
 	return 0;
@@ -171,41 +171,49 @@ void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function,
 	map->do_count_items = 1;
 }
 
-void hashmap_free(struct hashmap *map, int free_entries)
+void hashmap_free_(struct hashmap *map, ssize_t entry_offset)
 {
 	if (!map || !map->table)
 		return;
-	if (free_entries) {
+	if (entry_offset >= 0) { /* called by hashmap_free_entries */
 		struct hashmap_iter iter;
 		struct hashmap_entry *e;
+
 		hashmap_iter_init(map, &iter);
 		while ((e = hashmap_iter_next(&iter)))
-			free(e);
+			/*
+			 * like container_of, but using caller-calculated
+			 * offset (caller being hashmap_free_entries)
+			 */
+			free((char *)e - entry_offset);
 	}
 	free(map->table);
 	memset(map, 0, sizeof(*map));
 }
 
-void *hashmap_get(const struct hashmap *map, const void *key, const void *keydata)
+struct hashmap_entry *hashmap_get(const struct hashmap *map,
+				const struct hashmap_entry *key,
+				const void *keydata)
 {
 	return *find_entry_ptr(map, key, keydata);
 }
 
-void *hashmap_get_next(const struct hashmap *map, const void *entry)
+struct hashmap_entry *hashmap_get_next(const struct hashmap *map,
+			const struct hashmap_entry *entry)
 {
-	struct hashmap_entry *e = ((struct hashmap_entry *) entry)->next;
+	struct hashmap_entry *e = entry->next;
 	for (; e; e = e->next)
 		if (entry_equals(map, entry, e, NULL))
 			return e;
 	return NULL;
 }
 
-void hashmap_add(struct hashmap *map, void *entry)
+void hashmap_add(struct hashmap *map, struct hashmap_entry *entry)
 {
 	unsigned int b = bucket(map, entry);
 
 	/* add entry */
-	((struct hashmap_entry *) entry)->next = map->table[b];
+	entry->next = map->table[b];
 	map->table[b] = entry;
 
 	/* fix size and rehash if appropriate */
@@ -216,7 +224,9 @@ void hashmap_add(struct hashmap *map, void *entry)
 	}
 }
 
-void *hashmap_remove(struct hashmap *map, const void *key, const void *keydata)
+struct hashmap_entry *hashmap_remove(struct hashmap *map,
+					const struct hashmap_entry *key,
+					const void *keydata)
 {
 	struct hashmap_entry *old;
 	struct hashmap_entry **e = find_entry_ptr(map, key, keydata);
@@ -238,7 +248,8 @@ void *hashmap_remove(struct hashmap *map, const void *key, const void *keydata)
 	return old;
 }
 
-void *hashmap_put(struct hashmap *map, void *entry)
+struct hashmap_entry *hashmap_put(struct hashmap *map,
+				struct hashmap_entry *entry)
 {
 	struct hashmap_entry *old = hashmap_remove(map, entry, NULL);
 	hashmap_add(map, entry);
@@ -252,7 +263,7 @@ void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter)
 	iter->next = NULL;
 }
 
-void *hashmap_iter_next(struct hashmap_iter *iter)
+struct hashmap_entry *hashmap_iter_next(struct hashmap_iter *iter)
 {
 	struct hashmap_entry *current = iter->next;
 	for (;;) {
@@ -275,10 +286,15 @@ struct pool_entry {
 };
 
 static int pool_entry_cmp(const void *unused_cmp_data,
-			  const struct pool_entry *e1,
-			  const struct pool_entry *e2,
-			  const unsigned char *keydata)
+			  const struct hashmap_entry *eptr,
+			  const struct hashmap_entry *entry_or_key,
+			  const void *keydata)
 {
+	const struct pool_entry *e1, *e2;
+
+	e1 = container_of(eptr, const struct pool_entry, ent);
+	e2 = container_of(entry_or_key, const struct pool_entry, ent);
+
 	return e1->data != keydata &&
 	       (e1->len != e2->len || memcmp(e1->data, keydata, e1->len));
 }
@@ -290,18 +306,18 @@ const void *memintern(const void *data, size_t len)
 
 	/* initialize string pool hashmap */
 	if (!map.tablesize)
-		hashmap_init(&map, (hashmap_cmp_fn) pool_entry_cmp, NULL, 0);
+		hashmap_init(&map, pool_entry_cmp, NULL, 0);
 
 	/* lookup interned string in pool */
-	hashmap_entry_init(&key, memhash(data, len));
+	hashmap_entry_init(&key.ent, memhash(data, len));
 	key.len = len;
-	e = hashmap_get(&map, &key, data);
+	e = hashmap_get_entry(&map, &key, ent, data);
 	if (!e) {
 		/* not found: create it */
 		FLEX_ALLOC_MEM(e, data, data, len);
-		hashmap_entry_init(e, key.ent.hash);
+		hashmap_entry_init(&e->ent, key.ent.hash);
 		e->len = len;
-		hashmap_add(&map, e);
+		hashmap_add(&map, &e->ent);
 	}
 	return e->data;
 }