diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
commit | 6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch) | |
tree | a68f146d7fa01f0134297619fbe7e33db084e0aa /comm/third_party/json-c/linkhash.c | |
parent | Initial commit. (diff) | |
download | thunderbird-upstream.tar.xz thunderbird-upstream.zip |
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'comm/third_party/json-c/linkhash.c')
-rw-r--r-- | comm/third_party/json-c/linkhash.c | 716 |
1 files changed, 716 insertions, 0 deletions
diff --git a/comm/third_party/json-c/linkhash.c b/comm/third_party/json-c/linkhash.c new file mode 100644 index 0000000000..5e12c51e7c --- /dev/null +++ b/comm/third_party/json-c/linkhash.c @@ -0,0 +1,716 @@ +/* + * $Id: linkhash.c,v 1.4 2006/01/26 02:16:28 mclark Exp $ + * + * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd. + * Michael Clark <michael@metaparadigm.com> + * Copyright (c) 2009 Hewlett-Packard Development Company, L.P. + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the MIT license. See COPYING for details. + * + */ + +#include "config.h" + +#include <assert.h> +#include <limits.h> +#include <stdarg.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#ifdef HAVE_ENDIAN_H +#include <endian.h> /* attempt to define endianness */ +#endif + +#if defined(_MSC_VER) || defined(__MINGW32__) +#define WIN32_LEAN_AND_MEAN +#include <windows.h> /* Get InterlockedCompareExchange */ +#endif + +#include "linkhash.h" +#include "random_seed.h" + +/* hash functions */ +static unsigned long lh_char_hash(const void *k); +static unsigned long lh_perllike_str_hash(const void *k); +static lh_hash_fn *char_hash_fn = lh_char_hash; + +/* comparison functions */ +int lh_char_equal(const void *k1, const void *k2); +int lh_ptr_equal(const void *k1, const void *k2); + +int json_global_set_string_hash(const int h) +{ + switch (h) + { + case JSON_C_STR_HASH_DFLT: char_hash_fn = lh_char_hash; break; + case JSON_C_STR_HASH_PERLLIKE: char_hash_fn = lh_perllike_str_hash; break; + default: return -1; + } + return 0; +} + +static unsigned long lh_ptr_hash(const void *k) +{ + /* CAW: refactored to be 64bit nice */ + return (unsigned long)((((ptrdiff_t)k * LH_PRIME) >> 4) & ULONG_MAX); +} + +int lh_ptr_equal(const void *k1, const void *k2) +{ + return (k1 == k2); +} + +/* + * hashlittle from lookup3.c, by Bob Jenkins, May 2006, Public Domain. + * https://burtleburtle.net/bob/c/lookup3.c + * minor modifications to make functions static so no symbols are exported + * minor modifications to compile with -Werror + */ + +/* +------------------------------------------------------------------------------- +lookup3.c, by Bob Jenkins, May 2006, Public Domain. + +These are functions for producing 32-bit hashes for hash table lookup. +hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final() +are externally useful functions. Routines to test the hash are included +if SELF_TEST is defined. You can use this free for any purpose. It's in +the public domain. It has no warranty. + +You probably want to use hashlittle(). hashlittle() and hashbig() +hash byte arrays. hashlittle() is faster than hashbig() on +little-endian machines. Intel and AMD are little-endian machines. +On second thought, you probably want hashlittle2(), which is identical to +hashlittle() except it returns two 32-bit hashes for the price of one. +You could implement hashbig2() if you wanted but I haven't bothered here. + +If you want to find a hash of, say, exactly 7 integers, do + a = i1; b = i2; c = i3; + mix(a,b,c); + a += i4; b += i5; c += i6; + mix(a,b,c); + a += i7; + final(a,b,c); +then use c as the hash value. If you have a variable length array of +4-byte integers to hash, use hashword(). If you have a byte array (like +a character string), use hashlittle(). If you have several byte arrays, or +a mix of things, see the comments above hashlittle(). + +Why is this so big? I read 12 bytes at a time into 3 4-byte integers, +then mix those integers. This is fast (you can do a lot more thorough +mixing with 12*3 instructions on 3 integers than you can with 3 instructions +on 1 byte), but shoehorning those bytes into integers efficiently is messy. +------------------------------------------------------------------------------- +*/ + +/* + * My best guess at if you are big-endian or little-endian. This may + * need adjustment. + */ +#if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && __BYTE_ORDER == __LITTLE_ENDIAN) || \ + (defined(i386) || defined(__i386__) || defined(__i486__) || defined(__i586__) || \ + defined(__i686__) || defined(vax) || defined(MIPSEL)) +#define HASH_LITTLE_ENDIAN 1 +#define HASH_BIG_ENDIAN 0 +#elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && __BYTE_ORDER == __BIG_ENDIAN) || \ + (defined(sparc) || defined(POWERPC) || defined(mc68000) || defined(sel)) +#define HASH_LITTLE_ENDIAN 0 +#define HASH_BIG_ENDIAN 1 +#else +#define HASH_LITTLE_ENDIAN 0 +#define HASH_BIG_ENDIAN 0 +#endif + +#define hashsize(n) ((uint32_t)1 << (n)) +#define hashmask(n) (hashsize(n) - 1) +#define rot(x, k) (((x) << (k)) | ((x) >> (32 - (k)))) + +/* +------------------------------------------------------------------------------- +mix -- mix 3 32-bit values reversibly. + +This is reversible, so any information in (a,b,c) before mix() is +still in (a,b,c) after mix(). + +If four pairs of (a,b,c) inputs are run through mix(), or through +mix() in reverse, there are at least 32 bits of the output that +are sometimes the same for one pair and different for another pair. +This was tested for: +* pairs that differed by one bit, by two bits, in any combination + of top bits of (a,b,c), or in any combination of bottom bits of + (a,b,c). +* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed + the output delta to a Gray code (a^(a>>1)) so a string of 1's (as + is commonly produced by subtraction) look like a single 1-bit + difference. +* the base values were pseudorandom, all zero but one bit set, or + all zero plus a counter that starts at zero. + +Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that +satisfy this are + 4 6 8 16 19 4 + 9 15 3 18 27 15 + 14 9 3 7 17 3 +Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing +for "differ" defined as + with a one-bit base and a two-bit delta. I +used https://burtleburtle.net/bob/hash/avalanche.html to choose +the operations, constants, and arrangements of the variables. + +This does not achieve avalanche. There are input bits of (a,b,c) +that fail to affect some output bits of (a,b,c), especially of a. The +most thoroughly mixed value is c, but it doesn't really even achieve +avalanche in c. + +This allows some parallelism. Read-after-writes are good at doubling +the number of bits affected, so the goal of mixing pulls in the opposite +direction as the goal of parallelism. I did what I could. Rotates +seem to cost as much as shifts on every machine I could lay my hands +on, and rotates are much kinder to the top and bottom bits, so I used +rotates. +------------------------------------------------------------------------------- +*/ +/* clang-format off */ +#define mix(a,b,c) \ +{ \ + a -= c; a ^= rot(c, 4); c += b; \ + b -= a; b ^= rot(a, 6); a += c; \ + c -= b; c ^= rot(b, 8); b += a; \ + a -= c; a ^= rot(c,16); c += b; \ + b -= a; b ^= rot(a,19); a += c; \ + c -= b; c ^= rot(b, 4); b += a; \ +} +/* clang-format on */ + +/* +------------------------------------------------------------------------------- +final -- final mixing of 3 32-bit values (a,b,c) into c + +Pairs of (a,b,c) values differing in only a few bits will usually +produce values of c that look totally different. This was tested for +* pairs that differed by one bit, by two bits, in any combination + of top bits of (a,b,c), or in any combination of bottom bits of + (a,b,c). +* "differ" is defined as +, -, ^, or ~^. For + and -, I transformed + the output delta to a Gray code (a^(a>>1)) so a string of 1's (as + is commonly produced by subtraction) look like a single 1-bit + difference. +* the base values were pseudorandom, all zero but one bit set, or + all zero plus a counter that starts at zero. + +These constants passed: + 14 11 25 16 4 14 24 + 12 14 25 16 4 14 24 +and these came close: + 4 8 15 26 3 22 24 + 10 8 15 26 3 22 24 + 11 8 15 26 3 22 24 +------------------------------------------------------------------------------- +*/ +/* clang-format off */ +#define final(a,b,c) \ +{ \ + c ^= b; c -= rot(b,14); \ + a ^= c; a -= rot(c,11); \ + b ^= a; b -= rot(a,25); \ + c ^= b; c -= rot(b,16); \ + a ^= c; a -= rot(c,4); \ + b ^= a; b -= rot(a,14); \ + c ^= b; c -= rot(b,24); \ +} +/* clang-format on */ + +/* +------------------------------------------------------------------------------- +hashlittle() -- hash a variable-length key into a 32-bit value + k : the key (the unaligned variable-length array of bytes) + length : the length of the key, counting by bytes + initval : can be any 4-byte value +Returns a 32-bit value. Every bit of the key affects every bit of +the return value. Two keys differing by one or two bits will have +totally different hash values. + +The best hash table sizes are powers of 2. There is no need to do +mod a prime (mod is sooo slow!). If you need less than 32 bits, +use a bitmask. For example, if you need only 10 bits, do + h = (h & hashmask(10)); +In which case, the hash table should have hashsize(10) elements. + +If you are hashing n strings (uint8_t **)k, do it like this: + for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h); + +By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this +code any way you wish, private, educational, or commercial. It's free. + +Use for hash table lookup, or anything where one collision in 2^^32 is +acceptable. Do NOT use for cryptographic purposes. +------------------------------------------------------------------------------- +*/ + +/* clang-format off */ +static uint32_t hashlittle(const void *key, size_t length, uint32_t initval) +{ + uint32_t a,b,c; /* internal state */ + union + { + const void *ptr; + size_t i; + } u; /* needed for Mac Powerbook G4 */ + + /* Set up the internal state */ + a = b = c = 0xdeadbeef + ((uint32_t)length) + initval; + + u.ptr = key; + if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) { + const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */ + + /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */ + while (length > 12) + { + a += k[0]; + b += k[1]; + c += k[2]; + mix(a,b,c); + length -= 12; + k += 3; + } + + /*----------------------------- handle the last (probably partial) block */ + /* + * "k[2]&0xffffff" actually reads beyond the end of the string, but + * then masks off the part it's not allowed to read. Because the + * string is aligned, the masked-off tail is in the same word as the + * rest of the string. Every machine with memory protection I've seen + * does it on word boundaries, so is OK with this. But VALGRIND will + * still catch it and complain. The masking trick does make the hash + * noticeably faster for short strings (like English words). + * AddressSanitizer is similarly picky about overrunning + * the buffer. (https://clang.llvm.org/docs/AddressSanitizer.html) + */ +#ifdef VALGRIND +#define PRECISE_MEMORY_ACCESS 1 +#elif defined(__SANITIZE_ADDRESS__) /* GCC's ASAN */ +#define PRECISE_MEMORY_ACCESS 1 +#elif defined(__has_feature) +#if __has_feature(address_sanitizer) /* Clang's ASAN */ +#define PRECISE_MEMORY_ACCESS 1 +#endif +#endif +#ifndef PRECISE_MEMORY_ACCESS + + switch(length) + { + case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; + case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break; + case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break; + case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break; + case 8 : b+=k[1]; a+=k[0]; break; + case 7 : b+=k[1]&0xffffff; a+=k[0]; break; + case 6 : b+=k[1]&0xffff; a+=k[0]; break; + case 5 : b+=k[1]&0xff; a+=k[0]; break; + case 4 : a+=k[0]; break; + case 3 : a+=k[0]&0xffffff; break; + case 2 : a+=k[0]&0xffff; break; + case 1 : a+=k[0]&0xff; break; + case 0 : return c; /* zero length strings require no mixing */ + } + +#else /* make valgrind happy */ + + const uint8_t *k8 = (const uint8_t *)k; + switch(length) + { + case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; + case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ + case 10: c+=((uint32_t)k8[9])<<8; /* fall through */ + case 9 : c+=k8[8]; /* fall through */ + case 8 : b+=k[1]; a+=k[0]; break; + case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ + case 6 : b+=((uint32_t)k8[5])<<8; /* fall through */ + case 5 : b+=k8[4]; /* fall through */ + case 4 : a+=k[0]; break; + case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ + case 2 : a+=((uint32_t)k8[1])<<8; /* fall through */ + case 1 : a+=k8[0]; break; + case 0 : return c; + } + +#endif /* !valgrind */ + + } + else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) + { + const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */ + const uint8_t *k8; + + /*--------------- all but last block: aligned reads and different mixing */ + while (length > 12) + { + a += k[0] + (((uint32_t)k[1])<<16); + b += k[2] + (((uint32_t)k[3])<<16); + c += k[4] + (((uint32_t)k[5])<<16); + mix(a,b,c); + length -= 12; + k += 6; + } + + /*----------------------------- handle the last (probably partial) block */ + k8 = (const uint8_t *)k; + switch(length) + { + case 12: c+=k[4]+(((uint32_t)k[5])<<16); + b+=k[2]+(((uint32_t)k[3])<<16); + a+=k[0]+(((uint32_t)k[1])<<16); + break; + case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ + case 10: c+=k[4]; + b+=k[2]+(((uint32_t)k[3])<<16); + a+=k[0]+(((uint32_t)k[1])<<16); + break; + case 9 : c+=k8[8]; /* fall through */ + case 8 : b+=k[2]+(((uint32_t)k[3])<<16); + a+=k[0]+(((uint32_t)k[1])<<16); + break; + case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ + case 6 : b+=k[2]; + a+=k[0]+(((uint32_t)k[1])<<16); + break; + case 5 : b+=k8[4]; /* fall through */ + case 4 : a+=k[0]+(((uint32_t)k[1])<<16); + break; + case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ + case 2 : a+=k[0]; + break; + case 1 : a+=k8[0]; + break; + case 0 : return c; /* zero length requires no mixing */ + } + + } + else + { + /* need to read the key one byte at a time */ + const uint8_t *k = (const uint8_t *)key; + + /*--------------- all but the last block: affect some 32 bits of (a,b,c) */ + while (length > 12) + { + a += k[0]; + a += ((uint32_t)k[1])<<8; + a += ((uint32_t)k[2])<<16; + a += ((uint32_t)k[3])<<24; + b += k[4]; + b += ((uint32_t)k[5])<<8; + b += ((uint32_t)k[6])<<16; + b += ((uint32_t)k[7])<<24; + c += k[8]; + c += ((uint32_t)k[9])<<8; + c += ((uint32_t)k[10])<<16; + c += ((uint32_t)k[11])<<24; + mix(a,b,c); + length -= 12; + k += 12; + } + + /*-------------------------------- last block: affect all 32 bits of (c) */ + switch(length) /* all the case statements fall through */ + { + case 12: c+=((uint32_t)k[11])<<24; /* FALLTHRU */ + case 11: c+=((uint32_t)k[10])<<16; /* FALLTHRU */ + case 10: c+=((uint32_t)k[9])<<8; /* FALLTHRU */ + case 9 : c+=k[8]; /* FALLTHRU */ + case 8 : b+=((uint32_t)k[7])<<24; /* FALLTHRU */ + case 7 : b+=((uint32_t)k[6])<<16; /* FALLTHRU */ + case 6 : b+=((uint32_t)k[5])<<8; /* FALLTHRU */ + case 5 : b+=k[4]; /* FALLTHRU */ + case 4 : a+=((uint32_t)k[3])<<24; /* FALLTHRU */ + case 3 : a+=((uint32_t)k[2])<<16; /* FALLTHRU */ + case 2 : a+=((uint32_t)k[1])<<8; /* FALLTHRU */ + case 1 : a+=k[0]; + break; + case 0 : return c; + } + } + + final(a,b,c); + return c; +} +/* clang-format on */ + +/* a simple hash function similar to what perl does for strings. + * for good results, the string should not be excessively large. + */ +static unsigned long lh_perllike_str_hash(const void *k) +{ + const char *rkey = (const char *)k; + unsigned hashval = 1; + + while (*rkey) + hashval = hashval * 33 + *rkey++; + + return hashval; +} + +static unsigned long lh_char_hash(const void *k) +{ +#if defined _MSC_VER || defined __MINGW32__ +#define RANDOM_SEED_TYPE LONG +#else +#define RANDOM_SEED_TYPE int +#endif + static volatile RANDOM_SEED_TYPE random_seed = -1; + + if (random_seed == -1) + { + RANDOM_SEED_TYPE seed; + /* we can't use -1 as it is the uninitialized sentinel */ + while ((seed = json_c_get_random_seed()) == -1) {} +#if SIZEOF_INT == 8 && defined __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 +#define USE_SYNC_COMPARE_AND_SWAP 1 +#endif +#if SIZEOF_INT == 4 && defined __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 +#define USE_SYNC_COMPARE_AND_SWAP 1 +#endif +#if SIZEOF_INT == 2 && defined __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 +#define USE_SYNC_COMPARE_AND_SWAP 1 +#endif +#if defined USE_SYNC_COMPARE_AND_SWAP + (void)__sync_val_compare_and_swap(&random_seed, -1, seed); +#elif defined _MSC_VER || defined __MINGW32__ + InterlockedCompareExchange(&random_seed, seed, -1); +#else + //#warning "racy random seed initialization if used by multiple threads" + random_seed = seed; /* potentially racy */ +#endif + } + + return hashlittle((const char *)k, strlen((const char *)k), (uint32_t)random_seed); +} + +int lh_char_equal(const void *k1, const void *k2) +{ + return (strcmp((const char *)k1, (const char *)k2) == 0); +} + +struct lh_table *lh_table_new(int size, lh_entry_free_fn *free_fn, lh_hash_fn *hash_fn, + lh_equal_fn *equal_fn) +{ + int i; + struct lh_table *t; + + /* Allocate space for elements to avoid divisions by zero. */ + assert(size > 0); + t = (struct lh_table *)calloc(1, sizeof(struct lh_table)); + if (!t) + return NULL; + + t->count = 0; + t->size = size; + t->table = (struct lh_entry *)calloc(size, sizeof(struct lh_entry)); + if (!t->table) + { + free(t); + return NULL; + } + t->free_fn = free_fn; + t->hash_fn = hash_fn; + t->equal_fn = equal_fn; + for (i = 0; i < size; i++) + t->table[i].k = LH_EMPTY; + return t; +} + +struct lh_table *lh_kchar_table_new(int size, lh_entry_free_fn *free_fn) +{ + return lh_table_new(size, free_fn, char_hash_fn, lh_char_equal); +} + +struct lh_table *lh_kptr_table_new(int size, lh_entry_free_fn *free_fn) +{ + return lh_table_new(size, free_fn, lh_ptr_hash, lh_ptr_equal); +} + +int lh_table_resize(struct lh_table *t, int new_size) +{ + struct lh_table *new_t; + struct lh_entry *ent; + + new_t = lh_table_new(new_size, NULL, t->hash_fn, t->equal_fn); + if (new_t == NULL) + return -1; + + for (ent = t->head; ent != NULL; ent = ent->next) + { + unsigned long h = lh_get_hash(new_t, ent->k); + unsigned int opts = 0; + if (ent->k_is_constant) + opts = JSON_C_OBJECT_ADD_CONSTANT_KEY; + if (lh_table_insert_w_hash(new_t, ent->k, ent->v, h, opts) != 0) + { + lh_table_free(new_t); + return -1; + } + } + free(t->table); + t->table = new_t->table; + t->size = new_size; + t->head = new_t->head; + t->tail = new_t->tail; + free(new_t); + + return 0; +} + +void lh_table_free(struct lh_table *t) +{ + struct lh_entry *c; + if (t->free_fn) + { + for (c = t->head; c != NULL; c = c->next) + t->free_fn(c); + } + free(t->table); + free(t); +} + +int lh_table_insert_w_hash(struct lh_table *t, const void *k, const void *v, const unsigned long h, + const unsigned opts) +{ + unsigned long n; + + if (t->count >= t->size * LH_LOAD_FACTOR) + { + /* Avoid signed integer overflow with large tables. */ + int new_size = (t->size > INT_MAX / 2) ? INT_MAX : (t->size * 2); + if (t->size == INT_MAX || lh_table_resize(t, new_size) != 0) + return -1; + } + + n = h % t->size; + + while (1) + { + if (t->table[n].k == LH_EMPTY || t->table[n].k == LH_FREED) + break; + if ((int)++n == t->size) + n = 0; + } + + t->table[n].k = k; + t->table[n].k_is_constant = (opts & JSON_C_OBJECT_ADD_CONSTANT_KEY); + t->table[n].v = v; + t->count++; + + if (t->head == NULL) + { + t->head = t->tail = &t->table[n]; + t->table[n].next = t->table[n].prev = NULL; + } + else + { + t->tail->next = &t->table[n]; + t->table[n].prev = t->tail; + t->table[n].next = NULL; + t->tail = &t->table[n]; + } + + return 0; +} +int lh_table_insert(struct lh_table *t, const void *k, const void *v) +{ + return lh_table_insert_w_hash(t, k, v, lh_get_hash(t, k), 0); +} + +struct lh_entry *lh_table_lookup_entry_w_hash(struct lh_table *t, const void *k, + const unsigned long h) +{ + unsigned long n = h % t->size; + int count = 0; + + while (count < t->size) + { + if (t->table[n].k == LH_EMPTY) + return NULL; + if (t->table[n].k != LH_FREED && t->equal_fn(t->table[n].k, k)) + return &t->table[n]; + if ((int)++n == t->size) + n = 0; + count++; + } + return NULL; +} + +struct lh_entry *lh_table_lookup_entry(struct lh_table *t, const void *k) +{ + return lh_table_lookup_entry_w_hash(t, k, lh_get_hash(t, k)); +} + +json_bool lh_table_lookup_ex(struct lh_table *t, const void *k, void **v) +{ + struct lh_entry *e = lh_table_lookup_entry(t, k); + if (e != NULL) + { + if (v != NULL) + *v = lh_entry_v(e); + return 1; /* key found */ + } + if (v != NULL) + *v = NULL; + return 0; /* key not found */ +} + +int lh_table_delete_entry(struct lh_table *t, struct lh_entry *e) +{ + /* CAW: fixed to be 64bit nice, still need the crazy negative case... */ + ptrdiff_t n = (ptrdiff_t)(e - t->table); + + /* CAW: this is bad, really bad, maybe stack goes other direction on this machine... */ + if (n < 0) + { + return -2; + } + + if (t->table[n].k == LH_EMPTY || t->table[n].k == LH_FREED) + return -1; + t->count--; + if (t->free_fn) + t->free_fn(e); + t->table[n].v = NULL; + t->table[n].k = LH_FREED; + if (t->tail == &t->table[n] && t->head == &t->table[n]) + { + t->head = t->tail = NULL; + } + else if (t->head == &t->table[n]) + { + t->head->next->prev = NULL; + t->head = t->head->next; + } + else if (t->tail == &t->table[n]) + { + t->tail->prev->next = NULL; + t->tail = t->tail->prev; + } + else + { + t->table[n].prev->next = t->table[n].next; + t->table[n].next->prev = t->table[n].prev; + } + t->table[n].next = t->table[n].prev = NULL; + return 0; +} + +int lh_table_delete(struct lh_table *t, const void *k) +{ + struct lh_entry *e = lh_table_lookup_entry(t, k); + if (!e) + return -1; + return lh_table_delete_entry(t, e); +} + +int lh_table_length(struct lh_table *t) +{ + return t->count; +} |