X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fhash.c;h=df8f4bd615c25b3b022cf90efc9ddd300e3cfeab;hb=16a0854acae4ee4124c440b63b795859e33c92c7;hp=0c2d423cfe9079f9a5b35b9fcb583510a1248d2f;hpb=dabd3d823e0ecdf091976bee84bb742ddc2b2bad;p=gnulib.git diff --git a/lib/hash.c b/lib/hash.c index 0c2d423cf..df8f4bd61 100644 --- a/lib/hash.c +++ b/lib/hash.c @@ -61,6 +61,40 @@ char *malloc (); #include "hash.h" +struct hash_table + { + /* The array of buckets starts at BUCKET and extends to BUCKET_LIMIT-1, + for a possibility of N_BUCKETS. Among those, N_BUCKETS_USED buckets + are not empty, there are N_ENTRIES active entries in the table. */ + struct hash_entry *bucket; + struct hash_entry *bucket_limit; + unsigned n_buckets; + unsigned n_buckets_used; + unsigned n_entries; + + /* Tuning arguments, kept in a physicaly separate structure. */ + const Hash_tuning *tuning; + + /* Three functions are given to `hash_initialize', see the documentation + block for this function. In a word, HASHER randomizes a user entry + into a number up from 0 up to some maximum minus 1; COMPARATOR returns + true if two user entries compare equally; and DATA_FREER is the cleanup + function for a user entry. */ + Hash_hasher hasher; + Hash_comparator comparator; + Hash_data_freer data_freer; + + /* A linked list of freed struct hash_entry structs. */ + struct hash_entry *free_entry_list; + +#if USE_OBSTACK + /* Whenever obstacks are used, it is possible to allocate all overflowed + entries into a single stack, so they all can be freed in a single + operation. It is not clear if the speedup is worth the trouble. */ + struct obstack entry_stack; +#endif + }; + /* A hash table contains many internal entries, each holding a pointer to some user provided data (also called a user entry). An entry indistinctly refers to both the internal entry and its associated user entry. A user @@ -111,7 +145,7 @@ static const Hash_tuning default_tuning = DEFAULT_SHRINK_FACTOR, DEFAULT_GROWTH_THRESHOLD, DEFAULT_GROWTH_FACTOR, - 0 + false }; /* Information and lookup. */ @@ -576,19 +610,22 @@ void hash_clear (Hash_table *table) { struct hash_entry *bucket; - struct hash_entry *cursor; for (bucket = table->bucket; bucket < table->bucket_limit; bucket++) { if (bucket->data) { + struct hash_entry *cursor; + struct hash_entry *next; + /* Free the bucket overflow. */ - for (cursor = bucket->next; cursor; cursor = cursor->next) + for (cursor = bucket->next; cursor; cursor = next) { if (table->data_freer) (*table->data_freer) (cursor->data); cursor->data = NULL; + next = cursor->next; /* Relinking is done one entry at a time, as it is to be expected that overflows are either rare or short. */ cursor->next = table->free_entry_list; @@ -995,13 +1032,14 @@ hash_print (const Hash_table *table) struct hash_entry *cursor; if (bucket) - printf ("%d:\n", slot); + printf ("%d:\n", bucket - table->bucket); for (cursor = bucket; cursor; cursor = cursor->next) { char *s = (char *) cursor->data; /* FIXME */ - printf (" %s\n", s); + if (s) + printf (" %s\n", s); } } }