diff options
| -rw-r--r-- | Documentation/technical/api-hashmap.txt | 235 | ||||
| -rw-r--r-- | Makefile | 3 | ||||
| -rw-r--r-- | hashmap.c | 228 | ||||
| -rw-r--r-- | hashmap.h | 71 | ||||
| -rwxr-xr-x | t/t0011-hashmap.sh | 240 | ||||
| -rw-r--r-- | test-hashmap.c | 340 |
6 files changed, 1117 insertions, 0 deletions
diff --git a/Documentation/technical/api-hashmap.txt b/Documentation/technical/api-hashmap.txt new file mode 100644 index 0000000000..b2280f1b0d --- /dev/null +++ b/Documentation/technical/api-hashmap.txt @@ -0,0 +1,235 @@ +hashmap API +=========== + +The hashmap API is a generic implementation of hash-based key-value mappings. + +Data Structures +--------------- + +`struct hashmap`:: + + The hash table structure. ++ +The `size` member keeps track of the total number of entries. The `cmpfn` +member is a function used to compare two entries for equality. The `table` and +`tablesize` members store the hash table and its size, respectively. + +`struct hashmap_entry`:: + + An opaque structure representing an entry in the hash table, which must + be used as first member of user data structures. Ideally it should be + followed by an int-sized member to prevent unused memory on 64-bit + systems due to alignment. ++ +The `hash` member is the entry's hash code and the `next` member points to the +next entry in case of collisions (i.e. if multiple entries map to the same +bucket). + +`struct hashmap_iter`:: + + An iterator structure, to be used with hashmap_iter_* functions. + +Types +----- + +`int (*hashmap_cmp_fn)(const void *entry, const void *entry_or_key, const void *keydata)`:: + + User-supplied function to test two hashmap entries for equality. Shall + return 0 if the entries are equal. ++ +This function is always called with non-NULL `entry` / `entry_or_key` +parameters that have the same hash code. When looking up an entry, the `key` +and `keydata` parameters to hashmap_get and hashmap_remove are always passed +as second and third argument, respectively. Otherwise, `keydata` is NULL. + +Functions +--------- + +`unsigned int strhash(const char *buf)`:: +`unsigned int strihash(const char *buf)`:: +`unsigned int memhash(const void *buf, size_t len)`:: +`unsigned int memihash(const void *buf, size_t len)`:: + + Ready-to-use hash functions for strings, using the FNV-1 algorithm (see + http://www.isthe.com/chongo/tech/comp/fnv). ++ +`strhash` and `strihash` take 0-terminated strings, while `memhash` and +`memihash` operate on arbitrary-length memory. ++ +`strihash` and `memihash` are case insensitive versions. + +`void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function, size_t initial_size)`:: + + Initializes a hashmap structure. ++ +`map` is the hashmap to initialize. ++ +The `equals_function` can be specified to compare two entries for equality. +If NULL, entries are considered equal if their hash codes are equal. ++ +If the total number of entries is known in advance, the `initial_size` +parameter may be used to preallocate a sufficiently large table and thus +prevent expensive resizing. If 0, the table is dynamically resized. + +`void hashmap_free(struct hashmap *map, int free_entries)`:: + + Frees a hashmap structure and allocated memory. ++ +`map` is the hashmap to free. ++ +If `free_entries` is true, each hashmap_entry in the map is freed as well +(using stdlib's free()). + +`void hashmap_entry_init(void *entry, int hash)`:: + + Initializes a hashmap_entry structure. ++ +`entry` points to the entry to initialize. ++ +`hash` is the hash code of the entry. + +`void *hashmap_get(const struct hashmap *map, const void *key, const void *keydata)`:: + + Returns the hashmap entry for the specified key, or NULL if not found. ++ +`map` is the hashmap structure. ++ +`key` is a hashmap_entry structure (or user data structure that starts with +hashmap_entry) that has at least been initialized with the proper hash code +(via `hashmap_entry_init`). ++ +If an entry with matching hash code is found, `key` and `keydata` are passed +to `hashmap_cmp_fn` to decide whether the entry matches the key. + +`void *hashmap_get_next(const struct hashmap *map, const void *entry)`:: + + Returns the next equal hashmap entry, or NULL if not found. This can be + used to iterate over duplicate entries (see `hashmap_add`). ++ +`map` is the hashmap structure. ++ +`entry` is the hashmap_entry to start the search from, obtained via a previous +call to `hashmap_get` or `hashmap_get_next`. + +`void hashmap_add(struct hashmap *map, void *entry)`:: + + Adds a hashmap entry. This allows to add duplicate entries (i.e. + separate values with the same key according to hashmap_cmp_fn). ++ +`map` is the hashmap structure. ++ +`entry` is the entry to add. + +`void *hashmap_put(struct hashmap *map, void *entry)`:: + + Adds or replaces a hashmap entry. If the hashmap contains duplicate + entries equal to the specified entry, only one of them will be replaced. ++ +`map` is the hashmap structure. ++ +`entry` is the entry to add or replace. ++ +Returns the replaced entry, or NULL if not found (i.e. the entry was added). + +`void *hashmap_remove(struct hashmap *map, const void *key, const void *keydata)`:: + + Removes a hashmap entry matching the specified key. If the hashmap + contains duplicate entries equal to the specified key, only one of + them will be removed. ++ +`map` is the hashmap structure. ++ +`key` is a hashmap_entry structure (or user data structure that starts with +hashmap_entry) that has at least been initialized with the proper hash code +(via `hashmap_entry_init`). ++ +If an entry with matching hash code is found, `key` and `keydata` are +passed to `hashmap_cmp_fn` to decide whether the entry matches the key. ++ +Returns the removed entry, or NULL if not found. + +`void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter)`:: +`void *hashmap_iter_next(struct hashmap_iter *iter)`:: +`void *hashmap_iter_first(struct hashmap *map, struct hashmap_iter *iter)`:: + + Used to iterate over all entries of a hashmap. ++ +`hashmap_iter_init` initializes a `hashmap_iter` structure. ++ +`hashmap_iter_next` returns the next hashmap_entry, or NULL if there are no +more entries. ++ +`hashmap_iter_first` is a combination of both (i.e. initializes the iterator +and returns the first entry, if any). + +Usage example +------------- + +Here's a simple usage example that maps long keys to double values. +[source,c] +------------ +struct hashmap map; + +struct long2double { + struct hashmap_entry ent; /* must be the first member! */ + long key; + double value; +}; + +static int long2double_cmp(const struct long2double *e1, const struct long2double *e2, const void *unused) +{ + return !(e1->key == e2->key); +} + +void long2double_init(void) +{ + hashmap_init(&map, (hashmap_cmp_fn) long2double_cmp, 0); +} + +void long2double_free(void) +{ + hashmap_free(&map, 1); +} + +static struct long2double *find_entry(long key) +{ + struct long2double k; + hashmap_entry_init(&k, memhash(&key, sizeof(long))); + k.key = key; + return hashmap_get(&map, &k, NULL); +} + +double get_value(long key) +{ + struct long2double *e = find_entry(key); + return e ? e->value : 0; +} + +void set_value(long key, double value) +{ + struct long2double *e = find_entry(key); + if (!e) { + e = malloc(sizeof(struct long2double)); + hashmap_entry_init(e, memhash(&key, sizeof(long))); + e->key = key; + hashmap_add(&map, e); + } + e->value = value; +} +------------ + +Using variable-sized keys +------------------------- + +The `hashmap_entry_get` and `hashmap_entry_remove` functions expect an ordinary +`hashmap_entry` structure as key to find the correct entry. If the key data is +variable-sized (e.g. a FLEX_ARRAY string) or quite large, it is undesirable +to create a full-fledged entry structure on the heap and copy all the key data +into the structure. + +In this case, the `keydata` parameter can be used to pass +variable-sized key data directly to the comparison function, and the `key` +parameter can be a stripped-down, fixed size entry structure allocated on the +stack. + +See test-hashmap.c for an example using arbitrary-length strings as keys. @@ -557,6 +557,7 @@ TEST_PROGRAMS_NEED_X += test-date TEST_PROGRAMS_NEED_X += test-delta TEST_PROGRAMS_NEED_X += test-dump-cache-tree TEST_PROGRAMS_NEED_X += test-genrandom +TEST_PROGRAMS_NEED_X += test-hashmap TEST_PROGRAMS_NEED_X += test-index-version TEST_PROGRAMS_NEED_X += test-line-buffer TEST_PROGRAMS_NEED_X += test-match-trees @@ -677,6 +678,7 @@ LIB_H += gpg-interface.h LIB_H += graph.h LIB_H += grep.h LIB_H += hash.h +LIB_H += hashmap.h LIB_H += help.h LIB_H += http.h LIB_H += kwset.h @@ -808,6 +810,7 @@ LIB_OBJS += gpg-interface.o LIB_OBJS += graph.o LIB_OBJS += grep.o LIB_OBJS += hash.o +LIB_OBJS += hashmap.o LIB_OBJS += help.o LIB_OBJS += hex.o LIB_OBJS += ident.o diff --git a/hashmap.c b/hashmap.c new file mode 100644 index 0000000000..d1b8056d8d --- /dev/null +++ b/hashmap.c @@ -0,0 +1,228 @@ +/* + * Generic implementation of hash-based key value mappings. + */ +#include "cache.h" +#include "hashmap.h" + +#define FNV32_BASE ((unsigned int) 0x811c9dc5) +#define FNV32_PRIME ((unsigned int) 0x01000193) + +unsigned int strhash(const char *str) +{ + unsigned int c, hash = FNV32_BASE; + while ((c = (unsigned char) *str++)) + hash = (hash * FNV32_PRIME) ^ c; + return hash; +} + +unsigned int strihash(const char *str) +{ + unsigned int c, hash = FNV32_BASE; + while ((c = (unsigned char) *str++)) { + if (c >= 'a' && c <= 'z') + c -= 'a' - 'A'; + hash = (hash * FNV32_PRIME) ^ c; + } + return hash; +} + +unsigned int memhash(const void *buf, size_t len) +{ + unsigned int hash = FNV32_BASE; + unsigned char *ucbuf = (unsigned char *) buf; + while (len--) { + unsigned int c = *ucbuf++; + hash = (hash * FNV32_PRIME) ^ c; + } + return hash; +} + +unsigned int memihash(const void *buf, size_t len) +{ + unsigned int hash = FNV32_BASE; + unsigned char *ucbuf = (unsigned char *) buf; + while (len--) { + unsigned int c = *ucbuf++; + if (c >= 'a' && c <= 'z') + c -= 'a' - 'A'; + hash = (hash * FNV32_PRIME) ^ c; + } + return hash; +} + +#define HASHMAP_INITIAL_SIZE 64 +/* grow / shrink by 2^2 */ +#define HASHMAP_RESIZE_BITS 2 +/* load factor in percent */ +#define HASHMAP_LOAD_FACTOR 80 + +static void alloc_table(struct hashmap *map, unsigned int size) +{ + map->tablesize = size; + map->table = xcalloc(size, sizeof(struct hashmap_entry *)); + + /* calculate resize thresholds for new size */ + map->grow_at = (unsigned int) ((uint64_t) size * HASHMAP_LOAD_FACTOR / 100); + if (size <= HASHMAP_INITIAL_SIZE) + map->shrink_at = 0; + else + /* + * The shrink-threshold must be slightly smaller than + * (grow-threshold / resize-factor) to prevent erratic resizing, + * thus we divide by (resize-factor + 1). + */ + map->shrink_at = map->grow_at / ((1 << HASHMAP_RESIZE_BITS) + 1); +} + +static inline int entry_equals(const struct hashmap *map, + const struct hashmap_entry *e1, const struct hashmap_entry *e2, + const void *keydata) +{ + return (e1 == e2) || (e1->hash == e2->hash && !map->cmpfn(e1, e2, keydata)); +} + +static inline unsigned int bucket(const struct hashmap *map, + const struct hashmap_entry *key) +{ + return key->hash & (map->tablesize - 1); +} + +static void rehash(struct hashmap *map, unsigned int newsize) +{ + unsigned int i, oldsize = map->tablesize; + struct hashmap_entry **oldtable = map->table; + + alloc_table(map, newsize); + for (i = 0; i < oldsize; i++) { + struct hashmap_entry *e = oldtable[i]; + while (e) { + struct hashmap_entry *next = e->next; + unsigned int b = bucket(map, e); + e->next = map->table[b]; + map->table[b] = e; + e = next; + } + } + free(oldtable); +} + +static inline struct hashmap_entry **find_entry_ptr(const struct hashmap *map, + const struct hashmap_entry *key, const void *keydata) +{ + struct hashmap_entry **e = &map->table[bucket(map, key)]; + while (*e && !entry_equals(map, *e, key, keydata)) + e = &(*e)->next; + return e; +} + +static int always_equal(const void *unused1, const void *unused2, const void *unused3) +{ + return 0; +} + +void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function, + size_t initial_size) +{ + unsigned int size = HASHMAP_INITIAL_SIZE; + map->size = 0; + map->cmpfn = equals_function ? equals_function : always_equal; + + /* calculate initial table size and allocate the table */ + initial_size = (unsigned int) ((uint64_t) initial_size * 100 + / HASHMAP_LOAD_FACTOR); + while (initial_size > size) + size <<= HASHMAP_RESIZE_BITS; + alloc_table(map, size); +} + +void hashmap_free(struct hashmap *map, int free_entries) +{ + if (!map || !map->table) + return; + if (free_entries) { + struct hashmap_iter iter; + struct hashmap_entry *e; + hashmap_iter_init(map, &iter); + while ((e = hashmap_iter_next(&iter))) + free(e); + } + free(map->table); + memset(map, 0, sizeof(*map)); +} + +void *hashmap_get(const struct hashmap *map, const void *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 *e = ((struct hashmap_entry *) 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) +{ + unsigned int b = bucket(map, entry); + + /* add entry */ + ((struct hashmap_entry *) entry)->next = map->table[b]; + map->table[b] = entry; + + /* fix size and rehash if appropriate */ + map->size++; + if (map->size > map->grow_at) + rehash(map, map->tablesize << HASHMAP_RESIZE_BITS); +} + +void *hashmap_remove(struct hashmap *map, const void *key, const void *keydata) +{ + struct hashmap_entry *old; + struct hashmap_entry **e = find_entry_ptr(map, key, keydata); + if (!*e) + return NULL; + + /* remove existing entry */ + old = *e; + *e = old->next; + old->next = NULL; + + /* fix size and rehash if appropriate */ + map->size--; + if (map->size < map->shrink_at) + rehash(map, map->tablesize >> HASHMAP_RESIZE_BITS); + return old; +} + +void *hashmap_put(struct hashmap *map, void *entry) +{ + struct hashmap_entry *old = hashmap_remove(map, entry, NULL); + hashmap_add(map, entry); + return old; +} + +void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter) +{ + iter->map = map; + iter->tablepos = 0; + iter->next = NULL; +} + +void *hashmap_iter_next(struct hashmap_iter *iter) +{ + struct hashmap_entry *current = iter->next; + for (;;) { + if (current) { + iter->next = current->next; + return current; + } + + if (iter->tablepos >= iter->map->tablesize) + return NULL; + + current = iter->map->table[iter->tablepos++]; + } +} diff --git a/hashmap.h b/hashmap.h new file mode 100644 index 0000000000..f5b3b61073 --- /dev/null +++ b/hashmap.h @@ -0,0 +1,71 @@ +#ifndef HASHMAP_H +#define HASHMAP_H + +/* + * Generic implementation of hash-based key-value mappings. + * See Documentation/technical/api-hashmap.txt. + */ + +/* FNV-1 functions */ + +extern unsigned int strhash(const char *buf); +extern unsigned int strihash(const char *buf); +extern unsigned int memhash(const void *buf, size_t len); +extern unsigned int memihash(const void *buf, size_t len); + +/* data structures */ + +struct hashmap_entry { + struct hashmap_entry *next; + unsigned int hash; +}; + +typedef int (*hashmap_cmp_fn)(const void *entry, const void *entry_or_key, + const void *keydata); + +struct hashmap { + struct hashmap_entry **table; + hashmap_cmp_fn cmpfn; + unsigned int size, tablesize, grow_at, shrink_at; +}; + +struct hashmap_iter { + struct hashmap *map; + struct hashmap_entry *next; + unsigned int tablepos; +}; + +/* hashmap functions */ + +extern void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function, + size_t initial_size); +extern void hashmap_free(struct hashmap *map, int free_entries); + +/* hashmap_entry functions */ + +static inline void hashmap_entry_init(void *entry, int hash) +{ + struct hashmap_entry *e = entry; + e->hash = hash; + e->next = NULL; +} +extern void *hashmap_get(const struct hashmap *map, const void *key, + const void *keydata); +extern void *hashmap_get_next(const struct hashmap *map, const void *entry); +extern void hashmap_add(struct hashmap *map, void *entry); +extern void *hashmap_put(struct hashmap *map, void *entry); +extern void *hashmap_remove(struct hashmap *map, const void *key, + const void *keydata); + +/* hashmap_iter functions */ + +extern void hashmap_iter_init(struct hashmap *map, struct hashmap_iter *iter); +extern void *hashmap_iter_next(struct hashmap_iter *iter); +static inline void *hashmap_iter_first(struct hashmap *map, + struct hashmap_iter *iter) +{ + hashmap_iter_init(map, iter); + return hashmap_iter_next(iter); +} + +#endif diff --git a/t/t0011-hashmap.sh b/t/t0011-hashmap.sh new file mode 100755 index 0000000000..391e2b6492 --- /dev/null +++ b/t/t0011-hashmap.sh @@ -0,0 +1,240 @@ +#!/bin/sh + +test_description='test hashmap and string hash functions' +. ./test-lib.sh + +test_hashmap() { + echo "$1" | test-hashmap $3 > actual && + echo "$2" > expect && + test_cmp expect actual +} + +test_expect_success 'hash functions' ' + +test_hashmap "hash key1" "2215982743 2215982743 116372151 116372151" && +test_hashmap "hash key2" "2215982740 2215982740 116372148 116372148" && +test_hashmap "hash fooBarFrotz" "1383912807 1383912807 3189766727 3189766727" && +test_hashmap "hash foobarfrotz" "2862305959 2862305959 3189766727 3189766727" + +' + +test_expect_success 'put' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +put foobarfrotz value4 +size" "NULL +NULL +NULL +NULL +64 4" + +' + +test_expect_success 'put (case insensitive)' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +size" "NULL +NULL +NULL +64 3" ignorecase + +' + +test_expect_success 'replace' ' + +test_hashmap "put key1 value1 +put key1 value2 +put fooBarFrotz value3 +put fooBarFrotz value4 +size" "NULL +value1 +NULL +value3 +64 2" + +' + +test_expect_success 'replace (case insensitive)' ' + +test_hashmap "put key1 value1 +put Key1 value2 +put fooBarFrotz value3 +put foobarfrotz value4 +size" "NULL +value1 +NULL +value3 +64 2" ignorecase + +' + +test_expect_success 'get' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +put foobarfrotz value4 +get key1 +get key2 +get fooBarFrotz +get notInMap" "NULL +NULL +NULL +NULL +value1 +value2 +value3 +NULL" + +' + +test_expect_success 'get (case insensitive)' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +get Key1 +get keY2 +get foobarfrotz +get notInMap" "NULL +NULL +NULL +value1 +value2 +value3 +NULL" ignorecase + +' + +test_expect_success 'add' ' + +test_hashmap "add key1 value1 +add key1 value2 +add fooBarFrotz value3 +add fooBarFrotz value4 +get key1 +get fooBarFrotz +get notInMap" "value2 +value1 +value4 +value3 +NULL" + +' + +test_expect_success 'add (case insensitive)' ' + +test_hashmap "add key1 value1 +add Key1 value2 +add fooBarFrotz value3 +add foobarfrotz value4 +get key1 +get Foobarfrotz +get notInMap" "value2 +value1 +value4 +value3 +NULL" ignorecase + +' + +test_expect_success 'remove' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +remove key1 +remove key2 +remove notInMap +size" "NULL +NULL +NULL +value1 +value2 +NULL +64 1" + +' + +test_expect_success 'remove (case insensitive)' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +remove Key1 +remove keY2 +remove notInMap +size" "NULL +NULL +NULL +value1 +value2 +NULL +64 1" ignorecase + +' + +test_expect_success 'iterate' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +iterate" "NULL +NULL +NULL +key2 value2 +key1 value1 +fooBarFrotz value3" + +' + +test_expect_success 'iterate (case insensitive)' ' + +test_hashmap "put key1 value1 +put key2 value2 +put fooBarFrotz value3 +iterate" "NULL +NULL +NULL +fooBarFrotz value3 +key2 value2 +key1 value1" ignorecase + +' + +test_expect_success 'grow / shrink' ' + + rm -f in && + rm -f expect && + for n in $(test_seq 51) + do + echo put key$n value$n >> in && + echo NULL >> expect + done && + echo size >> in && + echo 64 51 >> expect && + echo put key52 value52 >> in && + echo NULL >> expect + echo size >> in && + echo 256 52 >> expect && + for n in $(test_seq 12) + do + echo remove key$n >> in && + echo value$n >> expect + done && + echo size >> in && + echo 256 40 >> expect && + echo remove key40 >> in && + echo value40 >> expect && + echo size >> in && + echo 64 39 >> expect && + cat in | test-hashmap > out && + test_cmp expect out + +' + +test_done diff --git a/test-hashmap.c b/test-hashmap.c new file mode 100644 index 0000000000..581d2964e4 --- /dev/null +++ b/test-hashmap.c @@ -0,0 +1,340 @@ +#include "cache.h" +#include "hashmap.h" +#include <stdio.h> + +struct test_entry +{ + struct hashmap_entry ent; + /* key and value as two \0-terminated strings */ + char key[FLEX_ARRAY]; +}; + +static const char *get_value(const struct test_entry *e) +{ + return e->key + strlen(e->key) + 1; +} + +static int test_entry_cmp(const struct test_entry *e1, + const struct test_entry *e2, const char* key) +{ + return strcmp(e1->key, key ? key : e2->key); +} + +static int test_entry_cmp_icase(const struct test_entry *e1, + const struct test_entry *e2, const char* key) +{ + return strcasecmp(e1->key, key ? key : e2->key); +} + +static struct test_entry *alloc_test_entry(int hash, char *key, int klen, + char *value, int vlen) +{ + struct test_entry *entry = malloc(sizeof(struct test_entry) + klen + + vlen + 2); + hashmap_entry_init(entry, hash); + memcpy(entry->key, key, klen + 1); + memcpy(entry->key + klen + 1, value, vlen + 1); + return entry; +} + +#define HASH_METHOD_FNV 0 +#define HASH_METHOD_I 1 +#define HASH_METHOD_IDIV10 2 +#define HASH_METHOD_0 3 +#define HASH_METHOD_X2 4 +#define TEST_SPARSE 8 +#define TEST_ADD 16 +#define TEST_SIZE 100000 + +static unsigned int hash(unsigned int method, unsigned int i, const char *key) +{ + unsigned int hash; + switch (method & 3) + { + case HASH_METHOD_FNV: + hash = strhash(key); + break; + case HASH_METHOD_I: + hash = i; + break; + case HASH_METHOD_IDIV10: + hash = i / 10; + break; + case HASH_METHOD_0: + hash = 0; + break; + } + + if (method & HASH_METHOD_X2) + hash = 2 * hash; + return hash; +} + +/* + * Test performance of hashmap.[ch] + * Usage: time echo "perfhashmap method rounds" | test-hashmap + */ +static void perf_hashmap(unsigned int method, unsigned int rounds) +{ + struct hashmap map; + char buf[16]; + struct test_entry **entries; + unsigned int *hashes; + unsigned int i, j; + + entries = malloc(TEST_SIZE * sizeof(struct test_entry *)); + hashes = malloc(TEST_SIZE * sizeof(int)); + for (i = 0; i < TEST_SIZE; i++) { + snprintf(buf, sizeof(buf), "%i", i); + entries[i] = alloc_test_entry(0, buf, strlen(buf), "", 0); + hashes[i] = hash(method, i, entries[i]->key); + } + + if (method & TEST_ADD) { + /* test adding to the map */ + for (j = 0; j < rounds; j++) { + hashmap_init(&map, (hashmap_cmp_fn) test_entry_cmp, 0); + + /* add entries */ + for (i = 0; i < TEST_SIZE; i++) { + hashmap_entry_init(entries[i], hashes[i]); + hashmap_add(&map, entries[i]); + } + + hashmap_free(&map, 0); + } + } else { + /* test map lookups */ + hashmap_init(&map, (hashmap_cmp_fn) test_entry_cmp, 0); + + /* fill the map (sparsely if specified) */ + j = (method & TEST_SPARSE) ? TEST_SIZE / 10 : TEST_SIZE; + for (i = 0; i < j; i++) { + hashmap_entry_init(entries[i], hashes[i]); + hashmap_add(&map, entries[i]); + } + + for (j = 0; j < rounds; j++) { + for (i = 0; i < TEST_SIZE; i++) { + struct hashmap_entry key; + hashmap_entry_init(&key, hashes[i]); + hashmap_get(&map, &key, entries[i]->key); + } + } + + hashmap_free(&map, 0); + } +} + +struct hash_entry +{ + struct hash_entry *next; + char key[FLEX_ARRAY]; +}; + +/* + * Test performance of hash.[ch] + * Usage: time echo "perfhash method rounds" | test-hashmap + */ +static void perf_hash(unsigned int method, unsigned int rounds) +{ + struct hash_table map; + char buf[16]; + struct hash_entry **entries, **res, *entry; + unsigned int *hashes; + unsigned int i, j; + + entries = malloc(TEST_SIZE * sizeof(struct hash_entry *)); + hashes = malloc(TEST_SIZE * sizeof(int)); + for (i = 0; i < TEST_SIZE; i++) { + snprintf(buf, sizeof(buf), "%i", i); + entries[i] = malloc(sizeof(struct hash_entry) + strlen(buf) + 1); + strcpy(entries[i]->key, buf); + hashes[i] = hash(method, i, entries[i]->key); + } + + if (method & TEST_ADD) { + /* test adding to the map */ + for (j = 0; j < rounds; j++) { + init_hash(&map); + + /* add entries */ + for (i = 0; i < TEST_SIZE; i++) { + res = (struct hash_entry **) insert_hash( + hashes[i], entries[i], &map); + if (res) { + entries[i]->next = *res; + *res = entries[i]; + } else { + entries[i]->next = NULL; + } + } + + free_hash(&map); + } + } else { + /* test map lookups */ + init_hash(&map); + + /* fill the map (sparsely if specified) */ + j = (method & TEST_SPARSE) ? TEST_SIZE / 10 : TEST_SIZE; + for (i = 0; i < j; i++) { + res = (struct hash_entry **) insert_hash(hashes[i], + entries[i], &map); + if (res) { + entries[i]->next = *res; + *res = entries[i]; + } else { + entries[i]->next = NULL; + } + } + + for (j = 0; j < rounds; j++) { + for (i = 0; i < TEST_SIZE; i++) { + entry = lookup_hash(hashes[i], &map); + while (entry) { + if (!strcmp(entries[i]->key, entry->key)) + break; + entry = entry->next; + } + } + } + + free_hash(&map); + + } +} + +#define DELIM " \t\r\n" + +/* + * Read stdin line by line and print result of commands to stdout: + * + * hash key -> strhash(key) memhash(key) strihash(key) memihash(key) + * put key value -> NULL / old value + * get key -> NULL / value + * remove key -> NULL / old value + * iterate -> key1 value1\nkey2 value2\n... + * size -> tablesize numentries + * + * perfhashmap method rounds -> test hashmap.[ch] performance + * perfhash method rounds -> test hash.[ch] performance + */ +int main(int argc, char *argv[]) +{ + char line[1024]; + struct hashmap map; + int icase; + + /* init hash map */ + icase = argc > 1 && !strcmp("ignorecase", argv[1]); + hashmap_init(&map, (hashmap_cmp_fn) (icase ? test_entry_cmp_icase + : test_entry_cmp), 0); + + /* process commands from stdin */ + while (fgets(line, sizeof(line), stdin)) { + char *cmd, *p1 = NULL, *p2 = NULL; + int l1 = 0, l2 = 0, hash = 0; + struct test_entry *entry; + + /* break line into command and up to two parameters */ + cmd = strtok(line, DELIM); + /* ignore empty lines */ + if (!cmd || *cmd == '#') + continue; + + p1 = strtok(NULL, DELIM); + if (p1) { + l1 = strlen(p1); + hash = icase ? strihash(p1) : strhash(p1); + p2 = strtok(NULL, DELIM); + if (p2) + l2 = strlen(p2); + } + + if (!strcmp("hash", cmd) && l1) { + + /* print results of different hash functions */ + printf("%u %u %u %u\n", strhash(p1), memhash(p1, l1), + strihash(p1), memihash(p1, l1)); + + } else if (!strcmp("add", cmd) && l1 && l2) { + + /* create entry with key = p1, value = p2 */ + entry = alloc_test_entry(hash, p1, l1, p2, l2); + + /* add to hashmap */ + hashmap_add(&map, entry); + + } else if (!strcmp("put", cmd) && l1 && l2) { + + /* create entry with key = p1, value = p2 */ + entry = alloc_test_entry(hash, p1, l1, p2, l2); + + /* add / replace entry */ + entry = hashmap_put(&map, entry); + + /* print and free replaced entry, if any */ + puts(entry ? get_value(entry) : "NULL"); + free(entry); + + } else if (!strcmp("get", cmd) && l1) { + + /* setup static key */ + struct hashmap_entry key; + hashmap_entry_init(&key, hash); + + /* lookup entry in hashmap */ + entry = hashmap_get(&map, &key, p1); + + /* print result */ + if (!entry) + puts("NULL"); + while (entry) { + puts(get_value(entry)); + entry = hashmap_get_next(&map, entry); + } + + } else if (!strcmp("remove", cmd) && l1) { + + /* setup static key */ + struct hashmap_entry key; + hashmap_entry_init(&key, hash); + + /* remove entry from hashmap */ + entry = hashmap_remove(&map, &key, p1); + + /* print result and free entry*/ + puts(entry ? get_value(entry) : "NULL"); + free(entry); + + } else if (!strcmp("iterate", cmd)) { + + struct hashmap_iter iter; + hashmap_iter_init(&map, &iter); + while ((entry = hashmap_iter_next(&iter))) + printf("%s %s\n", entry->key, get_value(entry)); + + } else if (!strcmp("size", cmd)) { + + /* print table sizes */ + printf("%u %u\n", map.tablesize, map.size); + + } else if (!strcmp("perfhashmap", cmd) && l1 && l2) { + + perf_hashmap(atoi(p1), atoi(p2)); + + } else if (!strcmp("perfhash", cmd) && l1 && l2) { + + perf_hash(atoi(p1), atoi(p2)); + + } else { + + printf("Unknown command %s\n", cmd); + + } + } + + hashmap_free(&map, 1); + return 0; +} |