/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2010 Lennart Poettering Copyright 2014 Michal Schmidt 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 <stdlib.h> #include <errno.h> #include "util.h" #include "hashmap.h" #include "set.h" #include "macro.h" #include "siphash24.h" #include "strv.h" #include "mempool.h" #include "random-util.h" #ifdef ENABLE_DEBUG_HASHMAP #include "list.h" #endif /* * Implementation of hashmaps. * Addressing: open * - uses less RAM compared to closed addressing (chaining), because * our entries are small (especially in Sets, which tend to contain * the majority of entries in systemd). * Collision resolution: Robin Hood * - tends to equalize displacement of entries from their optimal buckets. * Probe sequence: linear * - though theoretically worse than random probing/uniform hashing/double * hashing, it is good for cache locality. * * References: * Celis, P. 1986. Robin Hood Hashing. * Ph.D. Dissertation. University of Waterloo, Waterloo, Ont., Canada, Canada. * https://cs.uwaterloo.ca/research/tr/1986/CS-86-14.pdf * - The results are derived for random probing. Suggests deletion with * tombstones and two mean-centered search methods. None of that works * well for linear probing. * * Janson, S. 2005. Individual displacements for linear probing hashing with different insertion policies. * ACM Trans. Algorithms 1, 2 (October 2005), 177-213. * DOI=10.1145/1103963.1103964 http://doi.acm.org/10.1145/1103963.1103964 * http://www.math.uu.se/~svante/papers/sj157.pdf * - Applies to Robin Hood with linear probing. Contains remarks on * the unsuitability of mean-centered search with linear probing. * * Viola, A. 2005. Exact distribution of individual displacements in linear probing hashing. * ACM Trans. Algorithms 1, 2 (October 2005), 214-242. * DOI=10.1145/1103963.1103965 http://doi.acm.org/10.1145/1103963.1103965 * - Similar to Janson. Note that Viola writes about C_{m,n} (number of probes * in a successful search), and Janson writes about displacement. C = d + 1. * * Goossaert, E. 2013. Robin Hood hashing: backward shift deletion. * http://codecapsule.com/2013/11/17/robin-hood-hashing-backward-shift-deletion/ * - Explanation of backward shift deletion with pictures. * * Khuong, P. 2013. The Other Robin Hood Hashing. * http://www.pvk.ca/Blog/2013/11/26/the-other-robin-hood-hashing/ * - Short summary of random vs. linear probing, and tombstones vs. backward shift. */ /* * XXX Ideas for improvement: * For unordered hashmaps, randomize iteration order, similarly to Perl: * http://blog.booking.com/hardening-perls-hash-function.html */ /* INV_KEEP_FREE = 1 / (1 - max_load_factor) * e.g. 1 / (1 - 0.8) = 5 ... keep one fifth of the buckets free. */ #define INV_KEEP_FREE 5U /* Fields common to entries of all hashmap/set types */ struct hashmap_base_entry { const void *key; }; /* Entry types for specific hashmap/set types * hashmap_base_entry must be at the beginning of each entry struct. */ struct plain_hashmap_entry { struct hashmap_base_entry b; void *value; }; struct ordered_hashmap_entry { struct plain_hashmap_entry p; unsigned iterate_next, iterate_previous; }; struct set_entry { struct hashmap_base_entry b; }; /* In several functions it is advantageous to have the hash table extended * virtually by a couple of additional buckets. We reserve special index values * for these "swap" buckets. */ #define _IDX_SWAP_BEGIN (UINT_MAX - 3) #define IDX_PUT (_IDX_SWAP_BEGIN + 0) #define IDX_TMP (_IDX_SWAP_BEGIN + 1) #define _IDX_SWAP_END (_IDX_SWAP_BEGIN + 2) #define IDX_FIRST (UINT_MAX - 1) /* special index for freshly initialized iterators */ #define IDX_NIL UINT_MAX /* special index value meaning "none" or "end" */ assert_cc(IDX_FIRST == _IDX_SWAP_END); assert_cc(IDX_FIRST == _IDX_ITERATOR_FIRST); /* Storage space for the "swap" buckets. * All entry types can fit into a ordered_hashmap_entry. */ struct swap_entries { struct ordered_hashmap_entry e[_IDX_SWAP_END - _IDX_SWAP_BEGIN]; }; /* Distance from Initial Bucket */ typedef uint8_t dib_raw_t; #define DIB_RAW_OVERFLOW ((dib_raw_t)0xfdU) /* indicates DIB value is greater than representable */ #define DIB_RAW_REHASH ((dib_raw_t)0xfeU) /* entry yet to be rehashed during in-place resize */ #define DIB_RAW_FREE ((dib_raw_t)0xffU) /* a free bucket */ #define DIB_RAW_INIT ((char)DIB_RAW_FREE) /* a byte to memset a DIB store with when initializing */ #define DIB_FREE UINT_MAX #ifdef ENABLE_DEBUG_HASHMAP struct hashmap_debug_info { LIST_FIELDS(struct hashmap_debug_info, debug_list); unsigned max_entries; /* high watermark of n_entries */ /* who allocated this hashmap */ int line; const char *file; const char *func; /* fields to detect modification while iterating */ unsigned put_count; /* counts puts into the hashmap */ unsigned rem_count; /* counts removals from hashmap */ unsigned last_rem_idx; /* remembers last removal index */ }; /* Tracks all existing hashmaps. Get at it from gdb. See sd_dump_hashmaps.py */ static LIST_HEAD(struct hashmap_debug_info, hashmap_debug_list); #define HASHMAP_DEBUG_FIELDS struct hashmap_debug_info debug; #else /* !ENABLE_DEBUG_HASHMAP */ #define HASHMAP_DEBUG_FIELDS #endif /* ENABLE_DEBUG_HASHMAP */ enum HashmapType { HASHMAP_TYPE_PLAIN, HASHMAP_TYPE_ORDERED, HASHMAP_TYPE_SET, _HASHMAP_TYPE_MAX }; struct _packed_ indirect_storage { char *storage; /* where buckets and DIBs are stored */ uint8_t hash_key[HASH_KEY_SIZE]; /* hash key; changes during resize */ unsigned n_entries; /* number of stored entries */ unsigned n_buckets; /* number of buckets */ unsigned idx_lowest_entry; /* Index below which all buckets are free. Makes "while(hashmap_steal_first())" loops O(n) instead of O(n^2) for unordered hashmaps. */ uint8_t _pad[3]; /* padding for the whole HashmapBase */ /* The bitfields in HashmapBase complete the alignment of the whole thing. */ }; struct direct_storage { /* This gives us 39 bytes on 64bit, or 35 bytes on 32bit. * That's room for 4 set_entries + 4 DIB bytes + 3 unused bytes on 64bit, * or 7 set_entries + 7 DIB bytes + 0 unused bytes on 32bit. */ char storage[sizeof(struct indirect_storage)]; }; #define DIRECT_BUCKETS(entry_t) \ (sizeof(struct direct_storage) / (sizeof(entry_t) + sizeof(dib_raw_t))) /* We should be able to store at least one entry directly. */ assert_cc(DIRECT_BUCKETS(struct ordered_hashmap_entry) >= 1); /* We have 3 bits for n_direct_entries. */ assert_cc(DIRECT_BUCKETS(struct set_entry) < (1 << 3)); /* Hashmaps with directly stored entries all use this shared hash key. * It's no big deal if the key is guessed, because there can be only * a handful of directly stored entries in a hashmap. When a hashmap * outgrows direct storage, it gets its own key for indirect storage. */ static uint8_t shared_hash_key[HASH_KEY_SIZE]; static bool shared_hash_key_initialized; /* Fields that all hashmap/set types must have */ struct HashmapBase { const struct hash_ops *hash_ops; /* hash and compare ops to use */ union _packed_ { struct indirect_storage indirect; /* if has_indirect */ struct direct_storage direct; /* if !has_indirect */ }; enum HashmapType type:2; /* HASHMAP_TYPE_* */ bool has_indirect:1; /* whether indirect storage is used */ unsigned n_direct_entries:3; /* Number of entries in direct storage. * Only valid if !has_indirect. */ bool from_pool:1; /* whether was allocated from mempool */ HASHMAP_DEBUG_FIELDS /* optional hashmap_debug_info */ }; /* Specific hash types * HashmapBase must be at the beginning of each hashmap struct. */ struct Hashmap { struct HashmapBase b; }; struct OrderedHashmap { struct HashmapBase b; unsigned iterate_list_head, iterate_list_tail; }; struct Set { struct HashmapBase b; }; DEFINE_MEMPOOL(hashmap_pool, Hashmap, 8); DEFINE_MEMPOOL(ordered_hashmap_pool, OrderedHashmap, 8); /* No need for a separate Set pool */ assert_cc(sizeof(Hashmap) == sizeof(Set)); struct hashmap_type_info { size_t head_size; size_t entry_size; struct mempool *mempool; unsigned n_direct_buckets; }; static const struct hashmap_type_info hashmap_type_info[_HASHMAP_TYPE_MAX] = { [HASHMAP_TYPE_PLAIN] = { .head_size = sizeof(Hashmap), .entry_size = sizeof(struct plain_hashmap_entry), .mempool = &hashmap_pool, .n_direct_buckets = DIRECT_BUCKETS(struct plain_hashmap_entry), }, [HASHMAP_TYPE_ORDERED] = { .head_size = sizeof(OrderedHashmap), .entry_size = sizeof(struct ordered_hashmap_entry), .mempool = &ordered_hashmap_pool, .n_direct_buckets = DIRECT_BUCKETS(struct ordered_hashmap_entry), }, [HASHMAP_TYPE_SET] = { .head_size = sizeof(Set), .entry_size = sizeof(struct set_entry), .mempool = &hashmap_pool, .n_direct_buckets = DIRECT_BUCKETS(struct set_entry), }, }; unsigned long string_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) { uint64_t u; siphash24((uint8_t*) &u, p, strlen(p), hash_key); return (unsigned long) u; } int string_compare_func(const void *a, const void *b) { return strcmp(a, b); } const struct hash_ops string_hash_ops = { .hash = string_hash_func, .compare = string_compare_func }; unsigned long trivial_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) { uint64_t u; siphash24((uint8_t*) &u, &p, sizeof(p), hash_key); return (unsigned long) u; } int trivial_compare_func(const void *a, const void *b) { return a < b ? -1 : (a > b ? 1 : 0); } const struct hash_ops trivial_hash_ops = { .hash = trivial_hash_func, .compare = trivial_compare_func }; unsigned long uint64_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) { uint64_t u; siphash24((uint8_t*) &u, p, sizeof(uint64_t), hash_key); return (unsigned long) 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); } const struct hash_ops uint64_hash_ops = { .hash = uint64_hash_func, .compare = uint64_compare_func }; #if SIZEOF_DEV_T != 8 unsigned long devt_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) { uint64_t u; siphash24((uint8_t*) &u, p, sizeof(dev_t), hash_key); return (unsigned long) u; } int devt_compare_func(const void *_a, const void *_b) { dev_t a, b; a = *(const dev_t*) _a; b = *(const dev_t*) _b; return a < b ? -1 : (a > b ? 1 : 0); } const struct hash_ops devt_hash_ops = { .hash = devt_hash_func, .compare = devt_compare_func }; #endif static unsigned n_buckets(HashmapBase *h) { return h->has_indirect ? h->indirect.n_buckets : hashmap_type_info[h->type].n_direct_buckets; } static unsigned n_entries(HashmapBase *h) { return h->has_indirect ? h->indirect.n_entries : h->n_direct_entries; } static void n_entries_inc(HashmapBase *h) { if (h->has_indirect) h->indirect.n_entries++; else h->n_direct_entries++; } static void n_entries_dec(HashmapBase *h) { if (h->has_indirect) h->indirect.n_entries--; else h->n_direct_entries--; } static char *storage_ptr(HashmapBase *h) { return h->has_indirect ? h->indirect.storage : h->direct.storage; } static uint8_t *hash_key(HashmapBase *h) { return h->has_indirect ? h->indirect.hash_key : shared_hash_key; } static unsigned base_bucket_hash(HashmapBase *h, const void *p) { return (unsigned) (h->hash_ops->hash(p, hash_key(h)) % n_buckets(h)); } #define bucket_hash(h, p) base_bucket_hash(HASHMAP_BASE(h), p) static void get_hash_key(uint8_t hash_key[HASH_KEY_SIZE], bool reuse_is_ok) { static uint8_t current[HASH_KEY_SIZE]; static bool current_initialized = false; /* Returns a hash function key to use. In order to keep things * fast we will not generate a new key each time we allocate a * new hash table. Instead, we'll just reuse the most recently * generated one, except if we never generated one or when we * are rehashing an entire hash table because we reached a * fill level */ if (!current_initialized || !reuse_is_ok) { random_bytes(current, sizeof(current)); current_initialized = true; } memcpy(hash_key, current, sizeof(current)); } static struct hashmap_base_entry *bucket_at(HashmapBase *h, unsigned idx) { return (struct hashmap_base_entry*) (storage_ptr(h) + idx * hashmap_type_info[h->type].entry_size); } static struct plain_hashmap_entry *plain_bucket_at(Hashmap *h, unsigned idx) { return (struct plain_hashmap_entry*) bucket_at(HASHMAP_BASE(h), idx); } static struct ordered_hashmap_entry *ordered_bucket_at(OrderedHashmap *h, unsigned idx) { return (struct ordered_hashmap_entry*) bucket_at(HASHMAP_BASE(h), idx); } static struct set_entry *set_bucket_at(Set *h, unsigned idx) { return (struct set_entry*) bucket_at(HASHMAP_BASE(h), idx); } static struct ordered_hashmap_entry *bucket_at_swap(struct swap_entries *swap, unsigned idx) { return &swap->e[idx - _IDX_SWAP_BEGIN]; } /* Returns a pointer to the bucket at index idx. * Understands real indexes and swap indexes, hence "_virtual". */ static struct hashmap_base_entry *bucket_at_virtual(HashmapBase *h, struct swap_entries *swap, unsigned idx) { if (idx < _IDX_SWAP_BEGIN) return bucket_at(h, idx); if (idx < _IDX_SWAP_END) return &bucket_at_swap(swap, idx)->p.b; assert_not_reached("Invalid index"); } static dib_raw_t *dib_raw_ptr(HashmapBase *h) { return (dib_raw_t*) (storage_ptr(h) + hashmap_type_info[h->type].entry_size * n_buckets(h)); } static unsigned bucket_distance(HashmapBase *h, unsigned idx, unsigned from) { return idx >= from ? idx - from : n_buckets(h) + idx - from; } static unsigned bucket_calculate_dib(HashmapBase *h, unsigned idx, dib_raw_t raw_dib) { unsigned initial_bucket; if (raw_dib == DIB_RAW_FREE) return DIB_FREE; if (_likely_(raw_dib < DIB_RAW_OVERFLOW)) return raw_dib; /* * Having an overflow DIB value is very unlikely. The hash function * would have to be bad. For example, in a table of size 2^24 filled * to load factor 0.9 the maximum observed DIB is only about 60. * In theory (assuming I used Maxima correctly), for an infinite size * hash table with load factor 0.8 the probability of a given entry * having DIB > 40 is 1.9e-8. * This returns the correct DIB value by recomputing the hash value in * the unlikely case. XXX Hitting this case could be a hint to rehash. */ initial_bucket = bucket_hash(h, bucket_at(h, idx)->key); return bucket_distance(h, idx, initial_bucket); } static void bucket_set_dib(HashmapBase *h, unsigned idx, unsigned dib) { dib_raw_ptr(h)[idx] = dib != DIB_FREE ? MIN(dib, DIB_RAW_OVERFLOW) : DIB_RAW_FREE; } static unsigned skip_free_buckets(HashmapBase *h, unsigned idx) { dib_raw_t *dibs; dibs = dib_raw_ptr(h); for ( ; idx < n_buckets(h); idx++) if (dibs[idx] != DIB_RAW_FREE) return idx; return IDX_NIL; } static void bucket_mark_free(HashmapBase *h, unsigned idx) { memzero(bucket_at(h, idx), hashmap_type_info[h->type].entry_size); bucket_set_dib(h, idx, DIB_FREE); } static void bucket_move_entry(HashmapBase *h, struct swap_entries *swap, unsigned from, unsigned to) { struct hashmap_base_entry *e_from, *e_to; assert(from != to); e_from = bucket_at_virtual(h, swap, from); e_to = bucket_at_virtual(h, swap, to); memcpy(e_to, e_from, hashmap_type_info[h->type].entry_size); if (h->type == HASHMAP_TYPE_ORDERED) { OrderedHashmap *lh = (OrderedHashmap*) h; struct ordered_hashmap_entry *le, *le_to; le_to = (struct ordered_hashmap_entry*) e_to; if (le_to->iterate_next != IDX_NIL) { le = (struct ordered_hashmap_entry*) bucket_at_virtual(h, swap, le_to->iterate_next); le->iterate_previous = to; } if (le_to->iterate_previous != IDX_NIL) { le = (struct ordered_hashmap_entry*) bucket_at_virtual(h, swap, le_to->iterate_previous); le->iterate_next = to; } if (lh->iterate_list_head == from) lh->iterate_list_head = to; if (lh->iterate_list_tail == from) lh->iterate_list_tail = to; } } static unsigned next_idx(HashmapBase *h, unsigned idx) { return (idx + 1U) % n_buckets(h); } static unsigned prev_idx(HashmapBase *h, unsigned idx) { return (n_buckets(h) + idx - 1U) % n_buckets(h); } static void *entry_value(HashmapBase *h, struct hashmap_base_entry *e) { switch (h->type) { case HASHMAP_TYPE_PLAIN: case HASHMAP_TYPE_ORDERED: return ((struct plain_hashmap_entry*)e)->value; case HASHMAP_TYPE_SET: return (void*) e->key; default: assert_not_reached("Unknown hashmap type"); } } static void base_remove_entry(HashmapBase *h, unsigned idx) { unsigned left, right, prev, dib; dib_raw_t raw_dib, *dibs; dibs = dib_raw_ptr(h); assert(dibs[idx] != DIB_RAW_FREE); #ifdef ENABLE_DEBUG_HASHMAP h->debug.rem_count++; h->debug.last_rem_idx = idx; #endif left = idx; /* Find the stop bucket ("right"). It is either free or has DIB == 0. */ for (right = next_idx(h, left); ; right = next_idx(h, right)) { raw_dib = dibs[right]; if (raw_dib == 0 || raw_dib == DIB_RAW_FREE) break; /* The buckets are not supposed to be all occupied and with DIB > 0. * That would mean we could make everyone better off by shifting them * backward. This scenario is impossible. */ assert(left != right); } if (h->type == HASHMAP_TYPE_ORDERED) { OrderedHashmap *lh = (OrderedHashmap*) h; struct ordered_hashmap_entry *le = ordered_bucket_at(lh, idx); if (le->iterate_next != IDX_NIL) ordered_bucket_at(lh, le->iterate_next)->iterate_previous = le->iterate_previous; else lh->iterate_list_tail = le->iterate_previous; if (le->iterate_previous != IDX_NIL) ordered_bucket_at(lh, le->iterate_previous)->iterate_next = le->iterate_next; else lh->iterate_list_head = le->iterate_next; } /* Now shift all buckets in the interval (left, right) one step backwards */ for (prev = left, left = next_idx(h, left); left != right; prev = left, left = next_idx(h, left)) { dib = bucket_calculate_dib(h, left, dibs[left]); assert(dib != 0); bucket_move_entry(h, NULL, left, prev); bucket_set_dib(h, prev, dib - 1); } bucket_mark_free(h, prev); n_entries_dec(h); } #define remove_entry(h, idx) base_remove_entry(HASHMAP_BASE(h), idx) static unsigned hashmap_iterate_in_insertion_order(OrderedHashmap *h, Iterator *i) { struct ordered_hashmap_entry *e; unsigned idx; assert(h); assert(i); if (i->idx == IDX_NIL) goto at_end; if (i->idx == IDX_FIRST && h->iterate_list_head == IDX_NIL) goto at_end; if (i->idx == IDX_FIRST) { idx = h->iterate_list_head; e = ordered_bucket_at(h, idx); } else { idx = i->idx; e = ordered_bucket_at(h, idx); /* * We allow removing the current entry while iterating, but removal may cause * a backward shift. The next entry may thus move one bucket to the left. * To detect when it happens, we remember the key pointer of the entry we were * going to iterate next. If it does not match, there was a backward shift. */ if (e->p.b.key != i->next_key) { idx = prev_idx(HASHMAP_BASE(h), idx); e = ordered_bucket_at(h, idx); } assert(e->p.b.key == i->next_key); } #ifdef ENABLE_DEBUG_HASHMAP i->prev_idx = idx; #endif if (e->iterate_next != IDX_NIL) { struct ordered_hashmap_entry *n; i->idx = e->iterate_next; n = ordered_bucket_at(h, i->idx); i->next_key = n->p.b.key; } else i->idx = IDX_NIL; return idx; at_end: i->idx = IDX_NIL; return IDX_NIL; } static unsigned hashmap_iterate_in_internal_order(HashmapBase *h, Iterator *i) { unsigned idx; assert(h); assert(i); if (i->idx == IDX_NIL) goto at_end; if (i->idx == IDX_FIRST) { /* fast forward to the first occupied bucket */ if (h->has_indirect) { i->idx = skip_free_buckets(h, h->indirect.idx_lowest_entry); h->indirect.idx_lowest_entry = i->idx; } else i->idx = skip_free_buckets(h, 0); if (i->idx == IDX_NIL) goto at_end; } else { struct hashmap_base_entry *e; assert(i->idx > 0); e = bucket_at(h, i->idx); /* * We allow removing the current entry while iterating, but removal may cause * a backward shift. The next entry may thus move one bucket to the left. * To detect when it happens, we remember the key pointer of the entry we were * going to iterate next. If it does not match, there was a backward shift. */ if (e->key != i->next_key) e = bucket_at(h, --i->idx); assert(e->key == i->next_key); } idx = i->idx; #ifdef ENABLE_DEBUG_HASHMAP i->prev_idx = idx; #endif i->idx = skip_free_buckets(h, i->idx + 1); if (i->idx != IDX_NIL) i->next_key = bucket_at(h, i->idx)->key; else i->idx = IDX_NIL; return idx; at_end: i->idx = IDX_NIL; return IDX_NIL; } static unsigned hashmap_iterate_entry(HashmapBase *h, Iterator *i) { if (!h) { i->idx = IDX_NIL; return IDX_NIL; } #ifdef ENABLE_DEBUG_HASHMAP if (i->idx == IDX_FIRST) { i->put_count = h->debug.put_count; i->rem_count = h->debug.rem_count; } else { /* While iterating, must not add any new entries */ assert(i->put_count == h->debug.put_count); /* ... or remove entries other than the current one */ assert(i->rem_count == h->debug.rem_count || (i->rem_count == h->debug.rem_count - 1 && i->prev_idx == h->debug.last_rem_idx)); /* Reset our removals counter */ i->rem_count = h->debug.rem_count; } #endif return h->type == HASHMAP_TYPE_ORDERED ? hashmap_iterate_in_insertion_order((OrderedHashmap*) h, i) : hashmap_iterate_in_internal_order(h, i); } void *internal_hashmap_iterate(HashmapBase *h, Iterator *i, const void **key) { struct hashmap_base_entry *e; void *data; unsigned idx; idx = hashmap_iterate_entry(h, i); if (idx == IDX_NIL) { if (key) *key = NULL; return NULL; } e = bucket_at(h, idx); data = entry_value(h, e); if (key) *key = e->key; return data; } void *set_iterate(Set *s, Iterator *i) { return internal_hashmap_iterate(HASHMAP_BASE(s), i, NULL); } #define HASHMAP_FOREACH_IDX(idx, h, i) \ for ((i) = ITERATOR_FIRST, (idx) = hashmap_iterate_entry((h), &(i)); \ (idx != IDX_NIL); \ (idx) = hashmap_iterate_entry((h), &(i))) static void reset_direct_storage(HashmapBase *h) { const struct hashmap_type_info *hi = &hashmap_type_info[h->type]; void *p; assert(!h->has_indirect); p = mempset(h->direct.storage, 0, hi->entry_size * hi->n_direct_buckets); memset(p, DIB_RAW_INIT, sizeof(dib_raw_t) * hi->n_direct_buckets); } static struct HashmapBase *hashmap_base_new(const struct hash_ops *hash_ops, enum HashmapType type HASHMAP_DEBUG_PARAMS) { HashmapBase *h; const struct hashmap_type_info *hi = &hashmap_type_info[type]; bool use_pool; use_pool = is_main_thread(); h = use_pool ? mempool_alloc0_tile(hi->mempool) : malloc0(hi->head_size); if (!h) return NULL; h->type = type; h->from_pool = use_pool; h->hash_ops = hash_ops ? hash_ops : &trivial_hash_ops; if (type == HASHMAP_TYPE_ORDERED) { OrderedHashmap *lh = (OrderedHashmap*)h; lh->iterate_list_head = lh->iterate_list_tail = IDX_NIL; } reset_direct_storage(h); if (!shared_hash_key_initialized) { random_bytes(shared_hash_key, sizeof(shared_hash_key)); shared_hash_key_initialized= true; } #ifdef ENABLE_DEBUG_HASHMAP LIST_PREPEND(debug_list, hashmap_debug_list, &h->debug); h->debug.func = func; h->debug.file = file; h->debug.line = line; #endif return h; } Hashmap *internal_hashmap_new(const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return (Hashmap*) hashmap_base_new(hash_ops, HASHMAP_TYPE_PLAIN HASHMAP_DEBUG_PASS_ARGS); } OrderedHashmap *internal_ordered_hashmap_new(const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return (OrderedHashmap*) hashmap_base_new(hash_ops, HASHMAP_TYPE_ORDERED HASHMAP_DEBUG_PASS_ARGS); } Set *internal_set_new(const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return (Set*) hashmap_base_new(hash_ops, HASHMAP_TYPE_SET HASHMAP_DEBUG_PASS_ARGS); } static int hashmap_base_ensure_allocated(HashmapBase **h, const struct hash_ops *hash_ops, enum HashmapType type HASHMAP_DEBUG_PARAMS) { HashmapBase *q; assert(h); if (*h) return 0; q = hashmap_base_new(hash_ops, type HASHMAP_DEBUG_PASS_ARGS); if (!q) return -ENOMEM; *h = q; return 0; } int internal_hashmap_ensure_allocated(Hashmap **h, const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return hashmap_base_ensure_allocated((HashmapBase**)h, hash_ops, HASHMAP_TYPE_PLAIN HASHMAP_DEBUG_PASS_ARGS); } int internal_ordered_hashmap_ensure_allocated(OrderedHashmap **h, const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return hashmap_base_ensure_allocated((HashmapBase**)h, hash_ops, HASHMAP_TYPE_ORDERED HASHMAP_DEBUG_PASS_ARGS); } int internal_set_ensure_allocated(Set **s, const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS) { return hashmap_base_ensure_allocated((HashmapBase**)s, hash_ops, HASHMAP_TYPE_SET HASHMAP_DEBUG_PASS_ARGS); } static void hashmap_free_no_clear(HashmapBase *h) { assert(!h->has_indirect); assert(!h->n_direct_entries); #ifdef ENABLE_DEBUG_HASHMAP LIST_REMOVE(debug_list, hashmap_debug_list, &h->debug); #endif if (h->from_pool) mempool_free_tile(hashmap_type_info[h->type].mempool, h); else free(h); } HashmapBase *internal_hashmap_free(HashmapBase *h) { /* Free the hashmap, but nothing in it */ if (h) { internal_hashmap_clear(h); hashmap_free_no_clear(h); } return NULL; } HashmapBase *internal_hashmap_free_free(HashmapBase *h) { /* Free the hashmap and all data objects in it, but not the * keys */ if (h) { internal_hashmap_clear_free(h); hashmap_free_no_clear(h); } return NULL; } Hashmap *hashmap_free_free_free(Hashmap *h) { /* Free the hashmap and all data and key objects in it */ if (h) { hashmap_clear_free_free(h); hashmap_free_no_clear(HASHMAP_BASE(h)); } return NULL; } void internal_hashmap_clear(HashmapBase *h) { if (!h) return; if (h->has_indirect) { free(h->indirect.storage); h->has_indirect = false; } h->n_direct_entries = 0; reset_direct_storage(h); if (h->type == HASHMAP_TYPE_ORDERED) { OrderedHashmap *lh = (OrderedHashmap*) h; lh->iterate_list_head = lh->iterate_list_tail = IDX_NIL; } } void internal_hashmap_clear_free(HashmapBase *h) { unsigned idx; if (!h) return; for (idx = skip_free_buckets(h, 0); idx != IDX_NIL; idx = skip_free_buckets(h, idx + 1)) free(entry_value(h, bucket_at(h, idx))); internal_hashmap_clear(h); } void hashmap_clear_free_free(Hashmap *h) { unsigned idx; if (!h) return; for (idx = skip_free_buckets(HASHMAP_BASE(h), 0); idx != IDX_NIL; idx = skip_free_buckets(HASHMAP_BASE(h), idx + 1)) { struct plain_hashmap_entry *e = plain_bucket_at(h, idx); free((void*)e->b.key); free(e->value); } internal_hashmap_clear(HASHMAP_BASE(h)); } static int resize_buckets(HashmapBase *h, unsigned entries_add); /* * Finds an empty bucket to put an entry into, starting the scan at 'idx'. * Performs Robin Hood swaps as it goes. The entry to put must be placed * by the caller into swap slot IDX_PUT. * If used for in-place resizing, may leave a displaced entry in swap slot * IDX_PUT. Caller must rehash it next. * Returns: true if it left a displaced entry to rehash next in IDX_PUT, * false otherwise. */ static bool hashmap_put_robin_hood(HashmapBase *h, unsigned idx, struct swap_entries *swap) { dib_raw_t raw_dib, *dibs; unsigned dib, distance; #ifdef ENABLE_DEBUG_HASHMAP h->debug.put_count++; #endif dibs = dib_raw_ptr(h); for (distance = 0; ; distance++) { raw_dib = dibs[idx]; if (raw_dib == DIB_RAW_FREE || raw_dib == DIB_RAW_REHASH) { if (raw_dib == DIB_RAW_REHASH) bucket_move_entry(h, swap, idx, IDX_TMP); if (h->has_indirect && h->indirect.idx_lowest_entry > idx) h->indirect.idx_lowest_entry = idx; bucket_set_dib(h, idx, distance); bucket_move_entry(h, swap, IDX_PUT, idx); if (raw_dib == DIB_RAW_REHASH) { bucket_move_entry(h, swap, IDX_TMP, IDX_PUT); return true; } return false; } dib = bucket_calculate_dib(h, idx, raw_dib); if (dib < distance) { /* Found a wealthier entry. Go Robin Hood! */ bucket_set_dib(h, idx, distance); /* swap the entries */ bucket_move_entry(h, swap, idx, IDX_TMP); bucket_move_entry(h, swap, IDX_PUT, idx); bucket_move_entry(h, swap, IDX_TMP, IDX_PUT); distance = dib; } idx = next_idx(h, idx); } } /* * Puts an entry into a hashmap, boldly - no check whether key already exists. * The caller must place the entry (only its key and value, not link indexes) * in swap slot IDX_PUT. * Caller must ensure: the key does not exist yet in the hashmap. * that resize is not needed if !may_resize. * Returns: 1 if entry was put successfully. * -ENOMEM if may_resize==true and resize failed with -ENOMEM. * Cannot return -ENOMEM if !may_resize. */ static int hashmap_base_put_boldly(HashmapBase *h, unsigned idx, struct swap_entries *swap, bool may_resize) { struct ordered_hashmap_entry *new_entry; int r; assert(idx < n_buckets(h)); new_entry = bucket_at_swap(swap, IDX_PUT); if (may_resize) { r = resize_buckets(h, 1); if (r < 0) return r; if (r > 0) idx = bucket_hash(h, new_entry->p.b.key); } assert(n_entries(h) < n_buckets(h)); if (h->type == HASHMAP_TYPE_ORDERED) { OrderedHashmap *lh = (OrderedHashmap*) h; new_entry->iterate_next = IDX_NIL; new_entry->iterate_previous = lh->iterate_list_tail; if (lh->iterate_list_tail != IDX_NIL) { struct ordered_hashmap_entry *old_tail; old_tail = ordered_bucket_at(lh, lh->iterate_list_tail); assert(old_tail->iterate_next == IDX_NIL); old_tail->iterate_next = IDX_PUT; } lh->iterate_list_tail = IDX_PUT; if (lh->iterate_list_head == IDX_NIL) lh->iterate_list_head = IDX_PUT; } assert_se(hashmap_put_robin_hood(h, idx, swap) == false); n_entries_inc(h); #ifdef ENABLE_DEBUG_HASHMAP h->debug.max_entries = MAX(h->debug.max_entries, n_entries(h)); #endif return 1; } #define hashmap_put_boldly(h, idx, swap, may_resize) \ hashmap_base_put_boldly(HASHMAP_BASE(h), idx, swap, may_resize) /* * Returns 0 if resize is not needed. * 1 if successfully resized. * -ENOMEM on allocation failure. */ static int resize_buckets(HashmapBase *h, unsigned entries_add) { struct swap_entries swap; char *new_storage; dib_raw_t *old_dibs, *new_dibs; const struct hashmap_type_info *hi; unsigned idx, optimal_idx; unsigned old_n_buckets, new_n_buckets, n_rehashed, new_n_entries; uint8_t new_shift; bool rehash_next; assert(h); hi = &hashmap_type_info[h->type]; new_n_entries = n_entries(h) + entries_add; /* overflow? */ if (_unlikely_(new_n_entries < entries_add)) return -ENOMEM; /* For direct storage we allow 100% load, because it's tiny. */ if (!h->has_indirect && new_n_entries <= hi->n_direct_buckets) return 0; /* * Load factor = n/m = 1 - (1/INV_KEEP_FREE). * From it follows: m = n + n/(INV_KEEP_FREE - 1) */ new_n_buckets = new_n_entries + new_n_entries / (INV_KEEP_FREE - 1); /* overflow? */ if (_unlikely_(new_n_buckets < new_n_entries)) return -ENOMEM; if (_unlikely_(new_n_buckets > UINT_MAX / (hi->entry_size + sizeof(dib_raw_t)))) return -ENOMEM; old_n_buckets = n_buckets(h); if (_likely_(new_n_buckets <= old_n_buckets)) return 0; new_shift = log2u_round_up(MAX( new_n_buckets * (hi->entry_size + sizeof(dib_raw_t)), 2 * sizeof(struct direct_storage))); /* Realloc storage (buckets and DIB array). */ new_storage = realloc(h->has_indirect ? h->indirect.storage : NULL, 1U << new_shift); if (!new_storage) return -ENOMEM; /* Must upgrade direct to indirect storage. */ if (!h->has_indirect) { memcpy(new_storage, h->direct.storage, old_n_buckets * (hi->entry_size + sizeof(dib_raw_t))); h->indirect.n_entries = h->n_direct_entries; h->indirect.idx_lowest_entry = 0; h->n_direct_entries = 0; } /* Get a new hash key. If we've just upgraded to indirect storage, * allow reusing a previously generated key. It's still a different key * from the shared one that we used for direct storage. */ get_hash_key(h->indirect.hash_key, !h->has_indirect); h->has_indirect = true; h->indirect.storage = new_storage; h->indirect.n_buckets = (1U << new_shift) / (hi->entry_size + sizeof(dib_raw_t)); old_dibs = (dib_raw_t*)(new_storage + hi->entry_size * old_n_buckets); new_dibs = dib_raw_ptr(h); /* * Move the DIB array to the new place, replacing valid DIB values with * DIB_RAW_REHASH to indicate all of the used buckets need rehashing. * Note: Overlap is not possible, because we have at least doubled the * number of buckets and dib_raw_t is smaller than any entry type. */ for (idx = 0; idx < old_n_buckets; idx++) { assert(old_dibs[idx] != DIB_RAW_REHASH); new_dibs[idx] = old_dibs[idx] == DIB_RAW_FREE ? DIB_RAW_FREE : DIB_RAW_REHASH; } /* Zero the area of newly added entries (including the old DIB area) */ memzero(bucket_at(h, old_n_buckets), (n_buckets(h) - old_n_buckets) * hi->entry_size); /* The upper half of the new DIB array needs initialization */ memset(&new_dibs[old_n_buckets], DIB_RAW_INIT, (n_buckets(h) - old_n_buckets) * sizeof(dib_raw_t)); /* Rehash entries that need it */ n_rehashed = 0; for (idx = 0; idx < old_n_buckets; idx++) { if (new_dibs[idx] != DIB_RAW_REHASH) continue; optimal_idx = bucket_hash(h, bucket_at(h, idx)->key); /* * Not much to do if by luck the entry hashes to its current * location. Just set its DIB. */ if (optimal_idx == idx) { new_dibs[idx] = 0; n_rehashed++; continue; } new_dibs[idx] = DIB_RAW_FREE; bucket_move_entry(h, &swap, idx, IDX_PUT); /* bucket_move_entry does not clear the source */ memzero(bucket_at(h, idx), hi->entry_size); do { /* * Find the new bucket for the current entry. This may make * another entry homeless and load it into IDX_PUT. */ rehash_next = hashmap_put_robin_hood(h, optimal_idx, &swap); n_rehashed++; /* Did the current entry displace another one? */ if (rehash_next) optimal_idx = bucket_hash(h, bucket_at_swap(&swap, IDX_PUT)->p.b.key); } while (rehash_next); } assert(n_rehashed == n_entries(h)); return 1; } /* * Finds an entry with a matching key * Returns: index of the found entry, or IDX_NIL if not found. */ static unsigned base_bucket_scan(HashmapBase *h, unsigned idx, const void *key) { struct hashmap_base_entry *e; unsigned dib, distance; dib_raw_t *dibs = dib_raw_ptr(h); assert(idx < n_buckets(h)); for (distance = 0; ; distance++) { if (dibs[idx] == DIB_RAW_FREE) return IDX_NIL; dib = bucket_calculate_dib(h, idx, dibs[idx]); if (dib < distance) return IDX_NIL; if (dib == distance) { e = bucket_at(h, idx); if (h->hash_ops->compare(e->key, key) == 0) return idx; } idx = next_idx(h, idx); } } #define bucket_scan(h, idx, key) base_bucket_scan(HASHMAP_BASE(h), idx, key) int hashmap_put(Hashmap *h, const void *key, void *value) { struct swap_entries swap; struct plain_hashmap_entry *e; unsigned hash, idx; assert(h); hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx != IDX_NIL) { e = plain_bucket_at(h, idx); if (e->value == value) return 0; return -EEXIST; } e = &bucket_at_swap(&swap, IDX_PUT)->p; e->b.key = key; e->value = value; return hashmap_put_boldly(h, hash, &swap, true); } int set_put(Set *s, const void *key) { struct swap_entries swap; struct hashmap_base_entry *e; unsigned hash, idx; assert(s); hash = bucket_hash(s, key); idx = bucket_scan(s, hash, key); if (idx != IDX_NIL) return 0; e = &bucket_at_swap(&swap, IDX_PUT)->p.b; e->key = key; return hashmap_put_boldly(s, hash, &swap, true); } int hashmap_replace(Hashmap *h, const void *key, void *value) { struct swap_entries swap; struct plain_hashmap_entry *e; unsigned hash, idx; assert(h); hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx != IDX_NIL) { e = plain_bucket_at(h, idx); #ifdef ENABLE_DEBUG_HASHMAP /* Although the key is equal, the key pointer may have changed, * and this would break our assumption for iterating. So count * this operation as incompatible with iteration. */ if (e->b.key != key) { h->b.debug.put_count++; h->b.debug.rem_count++; h->b.debug.last_rem_idx = idx; } #endif e->b.key = key; e->value = value; return 0; } e = &bucket_at_swap(&swap, IDX_PUT)->p; e->b.key = key; e->value = value; return hashmap_put_boldly(h, hash, &swap, true); } int hashmap_update(Hashmap *h, const void *key, void *value) { struct plain_hashmap_entry *e; unsigned hash, idx; assert(h); hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return -ENOENT; e = plain_bucket_at(h, idx); e->value = value; return 0; } void *internal_hashmap_get(HashmapBase *h, const void *key) { struct hashmap_base_entry *e; unsigned hash, idx; if (!h) return NULL; hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return NULL; e = bucket_at(h, idx); return entry_value(h, e); } void *hashmap_get2(Hashmap *h, const void *key, void **key2) { struct plain_hashmap_entry *e; unsigned hash, idx; if (!h) return NULL; hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return NULL; e = plain_bucket_at(h, idx); if (key2) *key2 = (void*) e->b.key; return e->value; } bool internal_hashmap_contains(HashmapBase *h, const void *key) { unsigned hash; if (!h) return false; hash = bucket_hash(h, key); return bucket_scan(h, hash, key) != IDX_NIL; } void *internal_hashmap_remove(HashmapBase *h, const void *key) { struct hashmap_base_entry *e; unsigned hash, idx; void *data; if (!h) return NULL; hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return NULL; e = bucket_at(h, idx); data = entry_value(h, e); remove_entry(h, idx); return data; } void *hashmap_remove2(Hashmap *h, const void *key, void **rkey) { struct plain_hashmap_entry *e; unsigned hash, idx; void *data; if (!h) { if (rkey) *rkey = NULL; return NULL; } hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) { if (rkey) *rkey = NULL; return NULL; } e = plain_bucket_at(h, idx); data = e->value; if (rkey) *rkey = (void*) e->b.key; remove_entry(h, idx); return data; } int hashmap_remove_and_put(Hashmap *h, const void *old_key, const void *new_key, void *value) { struct swap_entries swap; struct plain_hashmap_entry *e; unsigned old_hash, new_hash, idx; if (!h) return -ENOENT; old_hash = bucket_hash(h, old_key); idx = bucket_scan(h, old_hash, old_key); if (idx == IDX_NIL) return -ENOENT; new_hash = bucket_hash(h, new_key); if (bucket_scan(h, new_hash, new_key) != IDX_NIL) return -EEXIST; remove_entry(h, idx); e = &bucket_at_swap(&swap, IDX_PUT)->p; e->b.key = new_key; e->value = value; assert_se(hashmap_put_boldly(h, new_hash, &swap, false) == 1); return 0; } int set_remove_and_put(Set *s, const void *old_key, const void *new_key) { struct swap_entries swap; struct hashmap_base_entry *e; unsigned old_hash, new_hash, idx; if (!s) return -ENOENT; old_hash = bucket_hash(s, old_key); idx = bucket_scan(s, old_hash, old_key); if (idx == IDX_NIL) return -ENOENT; new_hash = bucket_hash(s, new_key); if (bucket_scan(s, new_hash, new_key) != IDX_NIL) return -EEXIST; remove_entry(s, idx); e = &bucket_at_swap(&swap, IDX_PUT)->p.b; e->key = new_key; assert_se(hashmap_put_boldly(s, new_hash, &swap, false) == 1); return 0; } int hashmap_remove_and_replace(Hashmap *h, const void *old_key, const void *new_key, void *value) { struct swap_entries swap; struct plain_hashmap_entry *e; unsigned old_hash, new_hash, idx_old, idx_new; if (!h) return -ENOENT; old_hash = bucket_hash(h, old_key); idx_old = bucket_scan(h, old_hash, old_key); if (idx_old == IDX_NIL) return -ENOENT; old_key = bucket_at(HASHMAP_BASE(h), idx_old)->key; new_hash = bucket_hash(h, new_key); idx_new = bucket_scan(h, new_hash, new_key); if (idx_new != IDX_NIL) if (idx_old != idx_new) { remove_entry(h, idx_new); /* Compensate for a possible backward shift. */ if (old_key != bucket_at(HASHMAP_BASE(h), idx_old)->key) idx_old = prev_idx(HASHMAP_BASE(h), idx_old); assert(old_key == bucket_at(HASHMAP_BASE(h), idx_old)->key); } remove_entry(h, idx_old); e = &bucket_at_swap(&swap, IDX_PUT)->p; e->b.key = new_key; e->value = value; assert_se(hashmap_put_boldly(h, new_hash, &swap, false) == 1); return 0; } void *hashmap_remove_value(Hashmap *h, const void *key, void *value) { struct plain_hashmap_entry *e; unsigned hash, idx; if (!h) return NULL; hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return NULL; e = plain_bucket_at(h, idx); if (e->value != value) return NULL; remove_entry(h, idx); return value; } static unsigned find_first_entry(HashmapBase *h) { Iterator i = ITERATOR_FIRST; if (!h || !n_entries(h)) return IDX_NIL; return hashmap_iterate_entry(h, &i); } void *internal_hashmap_first(HashmapBase *h) { unsigned idx; idx = find_first_entry(h); if (idx == IDX_NIL) return NULL; return entry_value(h, bucket_at(h, idx)); } void *internal_hashmap_first_key(HashmapBase *h) { struct hashmap_base_entry *e; unsigned idx; idx = find_first_entry(h); if (idx == IDX_NIL) return NULL; e = bucket_at(h, idx); return (void*) e->key; } void *internal_hashmap_steal_first(HashmapBase *h) { struct hashmap_base_entry *e; void *data; unsigned idx; idx = find_first_entry(h); if (idx == IDX_NIL) return NULL; e = bucket_at(h, idx); data = entry_value(h, e); remove_entry(h, idx); return data; } void *internal_hashmap_steal_first_key(HashmapBase *h) { struct hashmap_base_entry *e; void *key; unsigned idx; idx = find_first_entry(h); if (idx == IDX_NIL) return NULL; e = bucket_at(h, idx); key = (void*) e->key; remove_entry(h, idx); return key; } unsigned internal_hashmap_size(HashmapBase *h) { if (!h) return 0; return n_entries(h); } unsigned internal_hashmap_buckets(HashmapBase *h) { if (!h) return 0; return n_buckets(h); } int internal_hashmap_merge(Hashmap *h, Hashmap *other) { Iterator i; unsigned idx; assert(h); HASHMAP_FOREACH_IDX(idx, HASHMAP_BASE(other), i) { struct plain_hashmap_entry *pe = plain_bucket_at(other, idx); int r; r = hashmap_put(h, pe->b.key, pe->value); if (r < 0 && r != -EEXIST) return r; } return 0; } int set_merge(Set *s, Set *other) { Iterator i; unsigned idx; assert(s); HASHMAP_FOREACH_IDX(idx, HASHMAP_BASE(other), i) { struct set_entry *se = set_bucket_at(other, idx); int r; r = set_put(s, se->b.key); if (r < 0) return r; } return 0; } int internal_hashmap_reserve(HashmapBase *h, unsigned entries_add) { int r; assert(h); r = resize_buckets(h, entries_add); if (r < 0) return r; return 0; } /* * The same as hashmap_merge(), but every new item from other is moved to h. * Keys already in h are skipped and stay in other. * Returns: 0 on success. * -ENOMEM on alloc failure, in which case no move has been done. */ int internal_hashmap_move(HashmapBase *h, HashmapBase *other) { struct swap_entries swap; struct hashmap_base_entry *e, *n; Iterator i; unsigned idx; int r; assert(h); if (!other) return 0; assert(other->type == h->type); /* * This reserves buckets for the worst case, where none of other's * entries are yet present in h. This is preferable to risking * an allocation failure in the middle of the moving and having to * rollback or return a partial result. */ r = resize_buckets(h, n_entries(other)); if (r < 0) return r; HASHMAP_FOREACH_IDX(idx, other, i) { unsigned h_hash; e = bucket_at(other, idx); h_hash = bucket_hash(h, e->key); if (bucket_scan(h, h_hash, e->key) != IDX_NIL) continue; n = &bucket_at_swap(&swap, IDX_PUT)->p.b; n->key = e->key; if (h->type != HASHMAP_TYPE_SET) ((struct plain_hashmap_entry*) n)->value = ((struct plain_hashmap_entry*) e)->value; assert_se(hashmap_put_boldly(h, h_hash, &swap, false) == 1); remove_entry(other, idx); } return 0; } int internal_hashmap_move_one(HashmapBase *h, HashmapBase *other, const void *key) { struct swap_entries swap; unsigned h_hash, other_hash, idx; struct hashmap_base_entry *e, *n; int r; assert(h); h_hash = bucket_hash(h, key); if (bucket_scan(h, h_hash, key) != IDX_NIL) return -EEXIST; if (!other) return -ENOENT; assert(other->type == h->type); other_hash = bucket_hash(other, key); idx = bucket_scan(other, other_hash, key); if (idx == IDX_NIL) return -ENOENT; e = bucket_at(other, idx); n = &bucket_at_swap(&swap, IDX_PUT)->p.b; n->key = e->key; if (h->type != HASHMAP_TYPE_SET) ((struct plain_hashmap_entry*) n)->value = ((struct plain_hashmap_entry*) e)->value; r = hashmap_put_boldly(h, h_hash, &swap, true); if (r < 0) return r; remove_entry(other, idx); return 0; } HashmapBase *internal_hashmap_copy(HashmapBase *h) { HashmapBase *copy; int r; assert(h); copy = hashmap_base_new(h->hash_ops, h->type HASHMAP_DEBUG_SRC_ARGS); if (!copy) return NULL; switch (h->type) { case HASHMAP_TYPE_PLAIN: case HASHMAP_TYPE_ORDERED: r = hashmap_merge((Hashmap*)copy, (Hashmap*)h); break; case HASHMAP_TYPE_SET: r = set_merge((Set*)copy, (Set*)h); break; default: assert_not_reached("Unknown hashmap type"); } if (r < 0) { internal_hashmap_free(copy); return NULL; } return copy; } char **internal_hashmap_get_strv(HashmapBase *h) { char **sv; Iterator i; unsigned idx, n; sv = new(char*, n_entries(h)+1); if (!sv) return NULL; n = 0; HASHMAP_FOREACH_IDX(idx, h, i) sv[n++] = entry_value(h, bucket_at(h, idx)); sv[n] = NULL; return sv; } void *ordered_hashmap_next(OrderedHashmap *h, const void *key) { struct ordered_hashmap_entry *e; unsigned hash, idx; assert(key); if (!h) return NULL; hash = bucket_hash(h, key); idx = bucket_scan(h, hash, key); if (idx == IDX_NIL) return NULL; e = ordered_bucket_at(h, idx); if (e->iterate_next == IDX_NIL) return NULL; return ordered_bucket_at(h, e->iterate_next)->p.value; } int set_consume(Set *s, void *value) { int r; r = set_put(s, value); if (r <= 0) free(value); return r; } int set_put_strdup(Set *s, const char *p) { char *c; int r; assert(s); assert(p); c = strdup(p); if (!c) return -ENOMEM; r = set_consume(s, c); if (r == -EEXIST) return 0; return r; } int set_put_strdupv(Set *s, char **l) { int n = 0, r; char **i; STRV_FOREACH(i, l) { r = set_put_strdup(s, *i); if (r < 0) return r; n += r; } return n; }