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-rw-r--r--src/libudev/hashmap.c835
1 files changed, 835 insertions, 0 deletions
diff --git a/src/libudev/hashmap.c b/src/libudev/hashmap.c
new file mode 100644
index 0000000000..dcfbb67228
--- /dev/null
+++ b/src/libudev/hashmap.c
@@ -0,0 +1,835 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "util.h"
+#include "hashmap.h"
+#include "macro.h"
+
+#define NBUCKETS 127
+
+struct hashmap_entry {
+ const void *key;
+ void *value;
+ struct hashmap_entry *bucket_next, *bucket_previous;
+ struct hashmap_entry *iterate_next, *iterate_previous;
+};
+
+struct Hashmap {
+ hash_func_t hash_func;
+ compare_func_t compare_func;
+
+ struct hashmap_entry *iterate_list_head, *iterate_list_tail;
+ unsigned n_entries;
+
+ bool from_pool;
+};
+
+#define BY_HASH(h) ((struct hashmap_entry**) ((uint8_t*) (h) + ALIGN(sizeof(Hashmap))))
+
+struct pool {
+ struct pool *next;
+ unsigned n_tiles;
+ unsigned n_used;
+};
+
+static struct pool *first_hashmap_pool = NULL;
+static void *first_hashmap_tile = NULL;
+
+static struct pool *first_entry_pool = NULL;
+static void *first_entry_tile = NULL;
+
+static void* allocate_tile(struct pool **first_pool, void **first_tile, size_t tile_size) {
+ unsigned i;
+
+ if (*first_tile) {
+ void *r;
+
+ r = *first_tile;
+ *first_tile = * (void**) (*first_tile);
+ return r;
+ }
+
+ if (_unlikely_(!*first_pool) || _unlikely_((*first_pool)->n_used >= (*first_pool)->n_tiles)) {
+ unsigned n;
+ size_t size;
+ struct pool *p;
+
+ n = *first_pool ? (*first_pool)->n_tiles : 0;
+ n = MAX(512U, n * 2);
+ size = PAGE_ALIGN(ALIGN(sizeof(struct pool)) + n*tile_size);
+ n = (size - ALIGN(sizeof(struct pool))) / tile_size;
+
+ p = malloc(size);
+ if (!p)
+ return NULL;
+
+ p->next = *first_pool;
+ p->n_tiles = n;
+ p->n_used = 0;
+
+ *first_pool = p;
+ }
+
+ i = (*first_pool)->n_used++;
+
+ return ((uint8_t*) (*first_pool)) + ALIGN(sizeof(struct pool)) + i*tile_size;
+}
+
+static void deallocate_tile(void **first_tile, void *p) {
+ * (void**) p = *first_tile;
+ *first_tile = p;
+}
+
+#ifndef __OPTIMIZE__
+
+static void drop_pool(struct pool *p) {
+ while (p) {
+ struct pool *n;
+ n = p->next;
+ free(p);
+ p = n;
+ }
+}
+
+__attribute__((destructor)) static void cleanup_pool(void) {
+ /* Be nice to valgrind */
+
+ drop_pool(first_hashmap_pool);
+ drop_pool(first_entry_pool);
+}
+
+#endif
+
+unsigned string_hash_func(const void *p) {
+ unsigned hash = 5381;
+ const signed char *c;
+
+ /* DJB's hash function */
+
+ for (c = p; *c; c++)
+ hash = (hash << 5) + hash + (unsigned) *c;
+
+ return hash;
+}
+
+int string_compare_func(const void *a, const void *b) {
+ return strcmp(a, b);
+}
+
+unsigned trivial_hash_func(const void *p) {
+ return PTR_TO_UINT(p);
+}
+
+int trivial_compare_func(const void *a, const void *b) {
+ return a < b ? -1 : (a > b ? 1 : 0);
+}
+
+unsigned uint64_hash_func(const void *p) {
+ uint64_t u;
+
+ assert_cc(sizeof(uint64_t) == 2*sizeof(unsigned));
+
+ u = *(const uint64_t*) p;
+
+ return (unsigned) ((u >> 32) ^ u);
+}
+
+int uint64_compare_func(const void *_a, const void *_b) {
+ uint64_t a, b;
+
+ a = *(const uint64_t*) _a;
+ b = *(const uint64_t*) _b;
+
+ return a < b ? -1 : (a > b ? 1 : 0);
+}
+
+Hashmap *hashmap_new(hash_func_t hash_func, compare_func_t compare_func) {
+ bool b;
+ Hashmap *h;
+ size_t size;
+
+ b = is_main_thread();
+
+ size = ALIGN(sizeof(Hashmap)) + NBUCKETS * sizeof(struct hashmap_entry*);
+
+ if (b) {
+ h = allocate_tile(&first_hashmap_pool, &first_hashmap_tile, size);
+ if (!h)
+ return NULL;
+
+ memset(h, 0, size);
+ } else {
+ h = malloc0(size);
+
+ if (!h)
+ return NULL;
+ }
+
+ h->hash_func = hash_func ? hash_func : trivial_hash_func;
+ h->compare_func = compare_func ? compare_func : trivial_compare_func;
+
+ h->n_entries = 0;
+ h->iterate_list_head = h->iterate_list_tail = NULL;
+
+ h->from_pool = b;
+
+ return h;
+}
+
+int hashmap_ensure_allocated(Hashmap **h, hash_func_t hash_func, compare_func_t compare_func) {
+ assert(h);
+
+ if (*h)
+ return 0;
+
+ if (!(*h = hashmap_new(hash_func, compare_func)))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void link_entry(Hashmap *h, struct hashmap_entry *e, unsigned hash) {
+ assert(h);
+ assert(e);
+
+ /* Insert into hash table */
+ e->bucket_next = BY_HASH(h)[hash];
+ e->bucket_previous = NULL;
+ if (BY_HASH(h)[hash])
+ BY_HASH(h)[hash]->bucket_previous = e;
+ BY_HASH(h)[hash] = e;
+
+ /* Insert into iteration list */
+ e->iterate_previous = h->iterate_list_tail;
+ e->iterate_next = NULL;
+ if (h->iterate_list_tail) {
+ assert(h->iterate_list_head);
+ h->iterate_list_tail->iterate_next = e;
+ } else {
+ assert(!h->iterate_list_head);
+ h->iterate_list_head = e;
+ }
+ h->iterate_list_tail = e;
+
+ h->n_entries++;
+ assert(h->n_entries >= 1);
+}
+
+static void unlink_entry(Hashmap *h, struct hashmap_entry *e, unsigned hash) {
+ assert(h);
+ assert(e);
+
+ /* Remove from iteration list */
+ if (e->iterate_next)
+ e->iterate_next->iterate_previous = e->iterate_previous;
+ else
+ h->iterate_list_tail = e->iterate_previous;
+
+ if (e->iterate_previous)
+ e->iterate_previous->iterate_next = e->iterate_next;
+ else
+ h->iterate_list_head = e->iterate_next;
+
+ /* Remove from hash table bucket list */
+ if (e->bucket_next)
+ e->bucket_next->bucket_previous = e->bucket_previous;
+
+ if (e->bucket_previous)
+ e->bucket_previous->bucket_next = e->bucket_next;
+ else
+ BY_HASH(h)[hash] = e->bucket_next;
+
+ assert(h->n_entries >= 1);
+ h->n_entries--;
+}
+
+static void remove_entry(Hashmap *h, struct hashmap_entry *e) {
+ unsigned hash;
+
+ assert(h);
+ assert(e);
+
+ hash = h->hash_func(e->key) % NBUCKETS;
+
+ unlink_entry(h, e, hash);
+
+ if (h->from_pool)
+ deallocate_tile(&first_entry_tile, e);
+ else
+ free(e);
+}
+
+void hashmap_free(Hashmap*h) {
+
+ /* Free the hashmap, but nothing in it */
+
+ if (!h)
+ return;
+
+ hashmap_clear(h);
+
+ if (h->from_pool)
+ deallocate_tile(&first_hashmap_tile, h);
+ else
+ free(h);
+}
+
+void hashmap_free_free(Hashmap *h) {
+
+ /* Free the hashmap and all data objects in it, but not the
+ * keys */
+
+ if (!h)
+ return;
+
+ hashmap_clear_free(h);
+ hashmap_free(h);
+}
+
+void hashmap_clear(Hashmap *h) {
+ if (!h)
+ return;
+
+ while (h->iterate_list_head)
+ remove_entry(h, h->iterate_list_head);
+}
+
+void hashmap_clear_free(Hashmap *h) {
+ void *p;
+
+ if (!h)
+ return;
+
+ while ((p = hashmap_steal_first(h)))
+ free(p);
+}
+
+static struct hashmap_entry *hash_scan(Hashmap *h, unsigned hash, const void *key) {
+ struct hashmap_entry *e;
+ assert(h);
+ assert(hash < NBUCKETS);
+
+ for (e = BY_HASH(h)[hash]; e; e = e->bucket_next)
+ if (h->compare_func(e->key, key) == 0)
+ return e;
+
+ return NULL;
+}
+
+int hashmap_put(Hashmap *h, const void *key, void *value) {
+ struct hashmap_entry *e;
+ unsigned hash;
+
+ assert(h);
+
+ hash = h->hash_func(key) % NBUCKETS;
+
+ e = hash_scan(h, hash, key);
+ if (e) {
+
+ if (e->value == value)
+ return 0;
+
+ return -EEXIST;
+ }
+
+ if (h->from_pool)
+ e = allocate_tile(&first_entry_pool, &first_entry_tile, sizeof(struct hashmap_entry));
+ else
+ e = new(struct hashmap_entry, 1);
+
+ if (!e)
+ return -ENOMEM;
+
+ e->key = key;
+ e->value = value;
+
+ link_entry(h, e, hash);
+
+ return 1;
+}
+
+int hashmap_replace(Hashmap *h, const void *key, void *value) {
+ struct hashmap_entry *e;
+ unsigned hash;
+
+ assert(h);
+
+ hash = h->hash_func(key) % NBUCKETS;
+ e = hash_scan(h, hash, key);
+ if (e) {
+ e->key = key;
+ e->value = value;
+ return 0;
+ }
+
+ return hashmap_put(h, key, value);
+}
+
+int hashmap_update(Hashmap *h, const void *key, void *value) {
+ struct hashmap_entry *e;
+ unsigned hash;
+
+ assert(h);
+
+ hash = h->hash_func(key) % NBUCKETS;
+ e = hash_scan(h, hash, key);
+ if (!e)
+ return -ENOENT;
+
+ e->value = value;
+ return 0;
+}
+
+void* hashmap_get(Hashmap *h, const void *key) {
+ unsigned hash;
+ struct hashmap_entry *e;
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+ e = hash_scan(h, hash, key);
+ if (!e)
+ return NULL;
+
+ return e->value;
+}
+
+void* hashmap_get2(Hashmap *h, const void *key, void **key2) {
+ unsigned hash;
+ struct hashmap_entry *e;
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+ e = hash_scan(h, hash, key);
+ if (!e)
+ return NULL;
+
+ if (key2)
+ *key2 = (void*) e->key;
+
+ return e->value;
+}
+
+bool hashmap_contains(Hashmap *h, const void *key) {
+ unsigned hash;
+
+ if (!h)
+ return false;
+
+ hash = h->hash_func(key) % NBUCKETS;
+
+ if (!hash_scan(h, hash, key))
+ return false;
+
+ return true;
+}
+
+void* hashmap_remove(Hashmap *h, const void *key) {
+ struct hashmap_entry *e;
+ unsigned hash;
+ void *data;
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+
+ if (!(e = hash_scan(h, hash, key)))
+ return NULL;
+
+ data = e->value;
+ remove_entry(h, e);
+
+ return data;
+}
+
+int hashmap_remove_and_put(Hashmap *h, const void *old_key, const void *new_key, void *value) {
+ struct hashmap_entry *e;
+ unsigned old_hash, new_hash;
+
+ if (!h)
+ return -ENOENT;
+
+ old_hash = h->hash_func(old_key) % NBUCKETS;
+ if (!(e = hash_scan(h, old_hash, old_key)))
+ return -ENOENT;
+
+ new_hash = h->hash_func(new_key) % NBUCKETS;
+ if (hash_scan(h, new_hash, new_key))
+ return -EEXIST;
+
+ unlink_entry(h, e, old_hash);
+
+ e->key = new_key;
+ e->value = value;
+
+ link_entry(h, e, new_hash);
+
+ return 0;
+}
+
+int hashmap_remove_and_replace(Hashmap *h, const void *old_key, const void *new_key, void *value) {
+ struct hashmap_entry *e, *k;
+ unsigned old_hash, new_hash;
+
+ if (!h)
+ return -ENOENT;
+
+ old_hash = h->hash_func(old_key) % NBUCKETS;
+ if (!(e = hash_scan(h, old_hash, old_key)))
+ return -ENOENT;
+
+ new_hash = h->hash_func(new_key) % NBUCKETS;
+
+ if ((k = hash_scan(h, new_hash, new_key)))
+ if (e != k)
+ remove_entry(h, k);
+
+ unlink_entry(h, e, old_hash);
+
+ e->key = new_key;
+ e->value = value;
+
+ link_entry(h, e, new_hash);
+
+ return 0;
+}
+
+void* hashmap_remove_value(Hashmap *h, const void *key, void *value) {
+ struct hashmap_entry *e;
+ unsigned hash;
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+
+ if (!(e = hash_scan(h, hash, key)))
+ return NULL;
+
+ if (e->value != value)
+ return NULL;
+
+ remove_entry(h, e);
+
+ return value;
+}
+
+void *hashmap_iterate(Hashmap *h, Iterator *i, const void **key) {
+ struct hashmap_entry *e;
+
+ assert(i);
+
+ if (!h)
+ goto at_end;
+
+ if (*i == ITERATOR_LAST)
+ goto at_end;
+
+ if (*i == ITERATOR_FIRST && !h->iterate_list_head)
+ goto at_end;
+
+ e = *i == ITERATOR_FIRST ? h->iterate_list_head : (struct hashmap_entry*) *i;
+
+ if (e->iterate_next)
+ *i = (Iterator) e->iterate_next;
+ else
+ *i = ITERATOR_LAST;
+
+ if (key)
+ *key = e->key;
+
+ return e->value;
+
+at_end:
+ *i = ITERATOR_LAST;
+
+ if (key)
+ *key = NULL;
+
+ return NULL;
+}
+
+void *hashmap_iterate_backwards(Hashmap *h, Iterator *i, const void **key) {
+ struct hashmap_entry *e;
+
+ assert(i);
+
+ if (!h)
+ goto at_beginning;
+
+ if (*i == ITERATOR_FIRST)
+ goto at_beginning;
+
+ if (*i == ITERATOR_LAST && !h->iterate_list_tail)
+ goto at_beginning;
+
+ e = *i == ITERATOR_LAST ? h->iterate_list_tail : (struct hashmap_entry*) *i;
+
+ if (e->iterate_previous)
+ *i = (Iterator) e->iterate_previous;
+ else
+ *i = ITERATOR_FIRST;
+
+ if (key)
+ *key = e->key;
+
+ return e->value;
+
+at_beginning:
+ *i = ITERATOR_FIRST;
+
+ if (key)
+ *key = NULL;
+
+ return NULL;
+}
+
+void *hashmap_iterate_skip(Hashmap *h, const void *key, Iterator *i) {
+ unsigned hash;
+ struct hashmap_entry *e;
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+
+ if (!(e = hash_scan(h, hash, key)))
+ return NULL;
+
+ *i = (Iterator) e;
+
+ return e->value;
+}
+
+void* hashmap_first(Hashmap *h) {
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_head)
+ return NULL;
+
+ return h->iterate_list_head->value;
+}
+
+void* hashmap_first_key(Hashmap *h) {
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_head)
+ return NULL;
+
+ return (void*) h->iterate_list_head->key;
+}
+
+void* hashmap_last(Hashmap *h) {
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_tail)
+ return NULL;
+
+ return h->iterate_list_tail->value;
+}
+
+void* hashmap_steal_first(Hashmap *h) {
+ void *data;
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_head)
+ return NULL;
+
+ data = h->iterate_list_head->value;
+ remove_entry(h, h->iterate_list_head);
+
+ return data;
+}
+
+void* hashmap_steal_first_key(Hashmap *h) {
+ void *key;
+
+ if (!h)
+ return NULL;
+
+ if (!h->iterate_list_head)
+ return NULL;
+
+ key = (void*) h->iterate_list_head->key;
+ remove_entry(h, h->iterate_list_head);
+
+ return key;
+}
+
+unsigned hashmap_size(Hashmap *h) {
+
+ if (!h)
+ return 0;
+
+ return h->n_entries;
+}
+
+bool hashmap_isempty(Hashmap *h) {
+
+ if (!h)
+ return true;
+
+ return h->n_entries == 0;
+}
+
+int hashmap_merge(Hashmap *h, Hashmap *other) {
+ struct hashmap_entry *e;
+
+ assert(h);
+
+ if (!other)
+ return 0;
+
+ for (e = other->iterate_list_head; e; e = e->iterate_next) {
+ int r;
+
+ if ((r = hashmap_put(h, e->key, e->value)) < 0)
+ if (r != -EEXIST)
+ return r;
+ }
+
+ return 0;
+}
+
+void hashmap_move(Hashmap *h, Hashmap *other) {
+ struct hashmap_entry *e, *n;
+
+ assert(h);
+
+ /* The same as hashmap_merge(), but every new item from other
+ * is moved to h. This function is guaranteed to succeed. */
+
+ if (!other)
+ return;
+
+ for (e = other->iterate_list_head; e; e = n) {
+ unsigned h_hash, other_hash;
+
+ n = e->iterate_next;
+
+ h_hash = h->hash_func(e->key) % NBUCKETS;
+
+ if (hash_scan(h, h_hash, e->key))
+ continue;
+
+ other_hash = other->hash_func(e->key) % NBUCKETS;
+
+ unlink_entry(other, e, other_hash);
+ link_entry(h, e, h_hash);
+ }
+}
+
+int hashmap_move_one(Hashmap *h, Hashmap *other, const void *key) {
+ unsigned h_hash, other_hash;
+ struct hashmap_entry *e;
+
+ if (!other)
+ return 0;
+
+ assert(h);
+
+ h_hash = h->hash_func(key) % NBUCKETS;
+ if (hash_scan(h, h_hash, key))
+ return -EEXIST;
+
+ other_hash = other->hash_func(key) % NBUCKETS;
+ if (!(e = hash_scan(other, other_hash, key)))
+ return -ENOENT;
+
+ unlink_entry(other, e, other_hash);
+ link_entry(h, e, h_hash);
+
+ return 0;
+}
+
+Hashmap *hashmap_copy(Hashmap *h) {
+ Hashmap *copy;
+
+ assert(h);
+
+ if (!(copy = hashmap_new(h->hash_func, h->compare_func)))
+ return NULL;
+
+ if (hashmap_merge(copy, h) < 0) {
+ hashmap_free(copy);
+ return NULL;
+ }
+
+ return copy;
+}
+
+char **hashmap_get_strv(Hashmap *h) {
+ char **sv;
+ Iterator it;
+ char *item;
+ int n;
+
+ sv = new(char*, h->n_entries+1);
+ if (!sv)
+ return NULL;
+
+ n = 0;
+ HASHMAP_FOREACH(item, h, it)
+ sv[n++] = item;
+ sv[n] = NULL;
+
+ return sv;
+}
+
+void *hashmap_next(Hashmap *h, const void *key) {
+ unsigned hash;
+ struct hashmap_entry *e;
+
+ assert(h);
+ assert(key);
+
+ if (!h)
+ return NULL;
+
+ hash = h->hash_func(key) % NBUCKETS;
+ e = hash_scan(h, hash, key);
+ if (!e)
+ return NULL;
+
+ e = e->iterate_next;
+ if (!e)
+ return NULL;
+
+ return e->value;
+}
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