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libxml2/hash.c
2024-05-20 14:23:39 +02:00

1346 lines
34 KiB
C

/*
* hash.c: hash tables
*
* Hash table with open addressing, linear probing and
* Robin Hood reordering.
*
* See Copyright for the status of this software.
*/
#define IN_LIBXML
#include "libxml.h"
#include <string.h>
#include <limits.h>
#include <libxml/parser.h>
#include <libxml/hash.h>
#include <libxml/dict.h>
#include <libxml/xmlmemory.h>
#include <libxml/xmlstring.h>
#include "private/dict.h"
#ifndef SIZE_MAX
#define SIZE_MAX ((size_t) -1)
#endif
#define MAX_FILL_NUM 7
#define MAX_FILL_DENOM 8
#define MIN_HASH_SIZE 8
#define MAX_HASH_SIZE (1u << 31)
/*
* A single entry in the hash table
*/
typedef struct {
unsigned hashValue; /* 0 means unoccupied, occupied entries have the
* MAX_HASH_SIZE bit set to 1 */
xmlChar *key;
xmlChar *key2; /* TODO: Don't allocate possibly empty keys */
xmlChar *key3;
void *payload;
} xmlHashEntry;
/*
* The entire hash table
*/
struct _xmlHashTable {
xmlHashEntry *table;
unsigned size; /* power of two */
unsigned nbElems;
xmlDictPtr dict;
unsigned randomSeed;
};
static int
xmlHashGrow(xmlHashTablePtr hash, unsigned size);
ATTRIBUTE_NO_SANITIZE_INTEGER
static unsigned
xmlHashValue(unsigned seed, const xmlChar *key, const xmlChar *key2,
const xmlChar *key3, size_t *lengths) {
unsigned h1, h2;
size_t i;
HASH_INIT(h1, h2, seed);
for (i = 0; key[i] != 0; i++) {
HASH_UPDATE(h1, h2, key[i]);
}
if (lengths)
lengths[0] = i;
HASH_UPDATE(h1, h2, 0);
if (key2 != NULL) {
for (i = 0; key2[i] != 0; i++) {
HASH_UPDATE(h1, h2, key2[i]);
}
if (lengths)
lengths[1] = i;
}
HASH_UPDATE(h1, h2, 0);
if (key3 != NULL) {
for (i = 0; key3[i] != 0; i++) {
HASH_UPDATE(h1, h2, key3[i]);
}
if (lengths)
lengths[2] = i;
}
HASH_FINISH(h1, h2);
return(h2);
}
ATTRIBUTE_NO_SANITIZE_INTEGER
static unsigned
xmlHashQNameValue(unsigned seed,
const xmlChar *prefix, const xmlChar *name,
const xmlChar *prefix2, const xmlChar *name2,
const xmlChar *prefix3, const xmlChar *name3) {
unsigned h1, h2, ch;
HASH_INIT(h1, h2, seed);
if (prefix != NULL) {
while ((ch = *prefix++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
HASH_UPDATE(h1, h2, ':');
}
if (name != NULL) {
while ((ch = *name++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
}
HASH_UPDATE(h1, h2, 0);
if (prefix2 != NULL) {
while ((ch = *prefix2++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
HASH_UPDATE(h1, h2, ':');
}
if (name2 != NULL) {
while ((ch = *name2++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
}
HASH_UPDATE(h1, h2, 0);
if (prefix3 != NULL) {
while ((ch = *prefix3++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
HASH_UPDATE(h1, h2, ':');
}
if (name3 != NULL) {
while ((ch = *name3++) != 0) {
HASH_UPDATE(h1, h2, ch);
}
}
HASH_FINISH(h1, h2);
return(h2);
}
/**
* xmlHashCreate:
* @size: initial size of the hash table
*
* Create a new hash table. Set size to zero if the number of entries
* can't be estimated.
*
* Returns the newly created object, or NULL if a memory allocation failed.
*/
xmlHashTablePtr
xmlHashCreate(int size) {
xmlHashTablePtr hash;
xmlInitParser();
hash = xmlMalloc(sizeof(*hash));
if (hash == NULL)
return(NULL);
hash->dict = NULL;
hash->size = 0;
hash->table = NULL;
hash->nbElems = 0;
hash->randomSeed = xmlRandom();
#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
hash->randomSeed = 0;
#endif
/*
* Unless a larger size is passed, the backing table is created
* lazily with MIN_HASH_SIZE capacity. In practice, there are many
* hash tables which are never filled.
*/
if (size > MIN_HASH_SIZE) {
unsigned newSize = MIN_HASH_SIZE * 2;
while ((newSize < (unsigned) size) && (newSize < MAX_HASH_SIZE))
newSize *= 2;
if (xmlHashGrow(hash, newSize) != 0) {
xmlFree(hash);
return(NULL);
}
}
return(hash);
}
/**
* xmlHashCreateDict:
* @size: the size of the hash table
* @dict: a dictionary to use for the hash
*
* Create a new hash table backed by a dictionary. This can reduce
* resource usage considerably if most keys passed to API functions
* originate from this dictionary.
*
* Returns the newly created object, or NULL if a memory allocation failed.
*/
xmlHashTablePtr
xmlHashCreateDict(int size, xmlDictPtr dict) {
xmlHashTablePtr hash;
hash = xmlHashCreate(size);
if (hash != NULL) {
hash->dict = dict;
xmlDictReference(dict);
}
return(hash);
}
/**
* xmlHashFree:
* @hash: hash table
* @dealloc: deallocator function or NULL
*
* Free the hash and its contents. The payload is deallocated with
* @dealloc if provided.
*/
void
xmlHashFree(xmlHashTablePtr hash, xmlHashDeallocator dealloc) {
if (hash == NULL)
return;
if (hash->table) {
const xmlHashEntry *end = &hash->table[hash->size];
const xmlHashEntry *entry;
for (entry = hash->table; entry < end; entry++) {
if (entry->hashValue == 0)
continue;
if ((dealloc != NULL) && (entry->payload != NULL))
dealloc(entry->payload, entry->key);
if (hash->dict == NULL) {
if (entry->key)
xmlFree(entry->key);
if (entry->key2)
xmlFree(entry->key2);
if (entry->key3)
xmlFree(entry->key3);
}
}
xmlFree(hash->table);
}
if (hash->dict)
xmlDictFree(hash->dict);
xmlFree(hash);
}
/**
* xmlFastStrEqual:
* @s1: string
* @s2: string
*
* Compare two strings for equality, allowing NULL values.
*/
static int
xmlFastStrEqual(const xmlChar *s1, const xmlChar *s2) {
if (s1 == NULL)
return(s2 == NULL);
else
return((s2 != NULL) &&
(strcmp((const char *) s1, (const char *) s2) == 0));
}
/**
* xmlHashFindEntry:
* @hash: hash table, non-NULL, size > 0
* @key: first string key, non-NULL
* @key2: second string key
* @key3: third string key
* @hashValue: valid hash value of keys
* @pfound: result of search
*
* Try to find a matching hash table entry. If an entry was found, set
* @found to 1 and return the entry. Otherwise, set @found to 0 and return
* the location where a new entry should be inserted.
*/
ATTRIBUTE_NO_SANITIZE_INTEGER
static xmlHashEntry *
xmlHashFindEntry(const xmlHashTable *hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
unsigned hashValue, int *pfound) {
xmlHashEntry *entry;
unsigned mask, pos, displ;
int found = 0;
mask = hash->size - 1;
pos = hashValue & mask;
entry = &hash->table[pos];
if (entry->hashValue != 0) {
/*
* Robin hood hashing: abort if the displacement of the entry
* is smaller than the displacement of the key we look for.
* This also stops at the correct position when inserting.
*/
displ = 0;
hashValue |= MAX_HASH_SIZE;
do {
if (entry->hashValue == hashValue) {
if (hash->dict) {
if ((entry->key == key) &&
(entry->key2 == key2) &&
(entry->key3 == key3)) {
found = 1;
break;
}
}
if ((strcmp((const char *) entry->key,
(const char *) key) == 0) &&
(xmlFastStrEqual(entry->key2, key2)) &&
(xmlFastStrEqual(entry->key3, key3))) {
found = 1;
break;
}
}
displ++;
pos++;
entry++;
if ((pos & mask) == 0)
entry = hash->table;
} while ((entry->hashValue != 0) &&
(((pos - entry->hashValue) & mask) >= displ));
}
*pfound = found;
return(entry);
}
/**
* xmlHashGrow:
* @hash: hash table
* @size: new size of the hash table
*
* Resize the hash table.
*
* Returns 0 in case of success, -1 if a memory allocation failed.
*/
static int
xmlHashGrow(xmlHashTablePtr hash, unsigned size) {
const xmlHashEntry *oldentry, *oldend, *end;
xmlHashEntry *table;
unsigned oldsize, i;
/* Add 0 to avoid spurious -Wtype-limits warning on 64-bit GCC */
if ((size_t) size + 0 > SIZE_MAX / sizeof(table[0]))
return(-1);
table = xmlMalloc(size * sizeof(table[0]));
if (table == NULL)
return(-1);
memset(table, 0, size * sizeof(table[0]));
oldsize = hash->size;
if (oldsize == 0)
goto done;
oldend = &hash->table[oldsize];
end = &table[size];
/*
* Robin Hood sorting order is maintained if we
*
* - compute hash indices with modulo
* - resize by an integer factor
* - start to copy from the beginning of a probe sequence
*/
oldentry = hash->table;
while (oldentry->hashValue != 0) {
if (++oldentry >= oldend)
oldentry = hash->table;
}
for (i = 0; i < oldsize; i++) {
if (oldentry->hashValue != 0) {
xmlHashEntry *entry = &table[oldentry->hashValue & (size - 1)];
while (entry->hashValue != 0) {
if (++entry >= end)
entry = table;
}
*entry = *oldentry;
}
if (++oldentry >= oldend)
oldentry = hash->table;
}
xmlFree(hash->table);
done:
hash->table = table;
hash->size = size;
return(0);
}
/**
* xmlHashUpdateInternal:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
* @payload: pointer to the payload
* @dealloc: deallocator function for replaced item or NULL
* @update: whether existing entries should be updated
*
* Internal function to add or update hash entries.
*/
ATTRIBUTE_NO_SANITIZE_INTEGER
static int
xmlHashUpdateInternal(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
void *payload, xmlHashDeallocator dealloc, int update) {
xmlChar *copy, *copy2, *copy3;
xmlHashEntry *entry = NULL;
size_t lengths[3];
unsigned hashValue;
int found = 0;
if ((hash == NULL) || (key == NULL))
return(-1);
/*
* Check for an existing entry
*/
hashValue = xmlHashValue(hash->randomSeed, key, key2, key3, lengths);
if (hash->size > 0)
entry = xmlHashFindEntry(hash, key, key2, key3, hashValue, &found);
if (found) {
if (update) {
if (dealloc)
dealloc(entry->payload, entry->key);
entry->payload = payload;
}
return(0);
}
/*
* Grow the hash table if needed
*/
if (hash->nbElems + 1 > hash->size / MAX_FILL_DENOM * MAX_FILL_NUM) {
unsigned newSize, mask, displ, pos;
if (hash->size == 0) {
newSize = MIN_HASH_SIZE;
} else {
/* This guarantees that nbElems < INT_MAX */
if (hash->size >= MAX_HASH_SIZE)
return(-1);
newSize = hash->size * 2;
}
if (xmlHashGrow(hash, newSize) != 0)
return(-1);
/*
* Find new entry
*/
mask = hash->size - 1;
displ = 0;
pos = hashValue & mask;
entry = &hash->table[pos];
if (entry->hashValue != 0) {
do {
displ++;
pos++;
entry++;
if ((pos & mask) == 0)
entry = hash->table;
} while ((entry->hashValue != 0) &&
((pos - entry->hashValue) & mask) >= displ);
}
}
/*
* Copy keys
*/
if (hash->dict != NULL) {
if (xmlDictOwns(hash->dict, key)) {
copy = (xmlChar *) key;
} else {
copy = (xmlChar *) xmlDictLookup(hash->dict, key, -1);
if (copy == NULL)
return(-1);
}
if ((key2 == NULL) || (xmlDictOwns(hash->dict, key2))) {
copy2 = (xmlChar *) key2;
} else {
copy2 = (xmlChar *) xmlDictLookup(hash->dict, key2, -1);
if (copy2 == NULL)
return(-1);
}
if ((key3 == NULL) || (xmlDictOwns(hash->dict, key3))) {
copy3 = (xmlChar *) key3;
} else {
copy3 = (xmlChar *) xmlDictLookup(hash->dict, key3, -1);
if (copy3 == NULL)
return(-1);
}
} else {
copy = xmlMalloc(lengths[0] + 1);
if (copy == NULL)
return(-1);
memcpy(copy, key, lengths[0] + 1);
if (key2 != NULL) {
copy2 = xmlMalloc(lengths[1] + 1);
if (copy2 == NULL) {
xmlFree(copy);
return(-1);
}
memcpy(copy2, key2, lengths[1] + 1);
} else {
copy2 = NULL;
}
if (key3 != NULL) {
copy3 = xmlMalloc(lengths[2] + 1);
if (copy3 == NULL) {
xmlFree(copy);
xmlFree(copy2);
return(-1);
}
memcpy(copy3, key3, lengths[2] + 1);
} else {
copy3 = NULL;
}
}
/*
* Shift the remainder of the probe sequence to the right
*/
if (entry->hashValue != 0) {
const xmlHashEntry *end = &hash->table[hash->size];
const xmlHashEntry *cur = entry;
do {
cur++;
if (cur >= end)
cur = hash->table;
} while (cur->hashValue != 0);
if (cur < entry) {
/*
* If we traversed the end of the buffer, handle the part
* at the start of the buffer.
*/
memmove(&hash->table[1], hash->table,
(char *) cur - (char *) hash->table);
cur = end - 1;
hash->table[0] = *cur;
}
memmove(&entry[1], entry, (char *) cur - (char *) entry);
}
/*
* Populate entry
*/
entry->key = copy;
entry->key2 = copy2;
entry->key3 = copy3;
entry->payload = payload;
/* OR with MAX_HASH_SIZE to make sure that the value is non-zero */
entry->hashValue = hashValue | MAX_HASH_SIZE;
hash->nbElems++;
return(1);
}
/**
* xmlHashDefaultDeallocator:
* @entry: hash table entry
* @key: the entry's string key
*
* Free a hash table entry with xmlFree.
*/
void
xmlHashDefaultDeallocator(void *entry, const xmlChar *key ATTRIBUTE_UNUSED) {
xmlFree(entry);
}
/**
* xmlHashAdd:
* @hash: hash table
* @key: string key
* @payload: pointer to the payload
*
* Add a hash table entry. If an entry with this key already exists,
* payload will not be updated and 0 is returned. This return value
* can't be distinguished from out-of-memory errors, so this function
* should be used with care.
*
* Available since 2.13.0.
*
* Returns 1 on success, 0 if an entry exists and -1 in case of error.
*/
int
xmlHashAdd(xmlHashTablePtr hash, const xmlChar *key, void *payload) {
return(xmlHashUpdateInternal(hash, key, NULL, NULL, payload, NULL, 0));
}
/**
* xmlHashAdd2:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @payload: pointer to the payload
*
* Add a hash table entry with two strings as key.
*
* See xmlHashAdd.
*
* Available since 2.13.0.
*
* Returns 1 on success, 0 if an entry exists and -1 in case of error.
*/
int
xmlHashAdd2(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, void *payload) {
return(xmlHashUpdateInternal(hash, key, key2, NULL, payload, NULL, 0));
}
/**
* xmlHashAdd3:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
* @payload: pointer to the payload
*
* Add a hash table entry with three strings as key.
*
* See xmlHashAdd.
*
* Available since 2.13.0.
*
* Returns 1 on success, 0 if an entry exists and -1 in case of error.
*/
int
xmlHashAdd3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
void *payload) {
return(xmlHashUpdateInternal(hash, key, key2, key3, payload, NULL, 0));
}
/**
* xmlHashAddEntry:
* @hash: hash table
* @key: string key
* @payload: pointer to the payload
*
* Add a hash table entry. If an entry with this key already exists,
* payload will not be updated and -1 is returned. This return value
* can't be distinguished from out-of-memory errors, so this function
* should be used with care.
*
* NOTE: This function doesn't allow to distinguish malloc failures from
* existing entries. Use xmlHashAdd instead.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashAddEntry(xmlHashTablePtr hash, const xmlChar *key, void *payload) {
int res = xmlHashUpdateInternal(hash, key, NULL, NULL, payload, NULL, 0);
if (res == 0)
res = -1;
else if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashAddEntry2:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @payload: pointer to the payload
*
* Add a hash table entry with two strings as key.
*
* See xmlHashAddEntry.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashAddEntry2(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, void *payload) {
int res = xmlHashUpdateInternal(hash, key, key2, NULL, payload, NULL, 0);
if (res == 0)
res = -1;
else if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashAddEntry3:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
* @payload: pointer to the payload
*
* Add a hash table entry with three strings as key.
*
* See xmlHashAddEntry.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashAddEntry3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
void *payload) {
int res = xmlHashUpdateInternal(hash, key, key2, key3, payload, NULL, 0);
if (res == 0)
res = -1;
else if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashUpdateEntry:
* @hash: hash table
* @key: string key
* @payload: pointer to the payload
* @dealloc: deallocator function for replaced item or NULL
*
* Add a hash table entry. If an entry with this key already exists,
* the old payload will be freed and updated with the new value.
*
* Returns 0 in case of success, -1 if a memory allocation failed.
*/
int
xmlHashUpdateEntry(xmlHashTablePtr hash, const xmlChar *key,
void *payload, xmlHashDeallocator dealloc) {
int res = xmlHashUpdateInternal(hash, key, NULL, NULL, payload,
dealloc, 1);
if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashUpdateEntry2:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @payload: pointer to the payload
* @dealloc: deallocator function for replaced item or NULL
*
* Add a hash table entry with two strings as key.
*
* See xmlHashUpdateEntry.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashUpdateEntry2(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, void *payload,
xmlHashDeallocator dealloc) {
int res = xmlHashUpdateInternal(hash, key, key2, NULL, payload,
dealloc, 1);
if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashUpdateEntry3:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
* @payload: pointer to the payload
* @dealloc: deallocator function for replaced item or NULL
*
* Add a hash table entry with three strings as key.
*
* See xmlHashUpdateEntry.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashUpdateEntry3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
void *payload, xmlHashDeallocator dealloc) {
int res = xmlHashUpdateInternal(hash, key, key2, key3, payload,
dealloc, 1);
if (res == 1)
res = 0;
return(res);
}
/**
* xmlHashLookup:
* @hash: hash table
* @key: string key
*
* Find the entry specified by @key.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
void *
xmlHashLookup(xmlHashTablePtr hash, const xmlChar *key) {
return(xmlHashLookup3(hash, key, NULL, NULL));
}
/**
* xmlHashLookup2:
* @hash: hash table
* @key: first string key
* @key2: second string key
*
* Find the payload specified by the (@key, @key2) tuple.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
void *
xmlHashLookup2(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2) {
return(xmlHashLookup3(hash, key, key2, NULL));
}
/**
* xmlHashQLookup:
* @hash: hash table
* @prefix: prefix of the string key
* @name: local name of the string key
*
* Find the payload specified by the QName @prefix:@name or @name.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
void *
xmlHashQLookup(xmlHashTablePtr hash, const xmlChar *prefix,
const xmlChar *name) {
return(xmlHashQLookup3(hash, prefix, name, NULL, NULL, NULL, NULL));
}
/**
* xmlHashQLookup2:
* @hash: hash table
* @prefix: first prefix
* @name: first local name
* @prefix2: second prefix
* @name2: second local name
*
* Find the payload specified by the QNames tuple.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
void *
xmlHashQLookup2(xmlHashTablePtr hash, const xmlChar *prefix,
const xmlChar *name, const xmlChar *prefix2,
const xmlChar *name2) {
return(xmlHashQLookup3(hash, prefix, name, prefix2, name2, NULL, NULL));
}
/**
* xmlHashLookup3:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
*
* Find the payload specified by the (@key, @key2, @key3) tuple.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
void *
xmlHashLookup3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3) {
const xmlHashEntry *entry;
unsigned hashValue;
int found;
if ((hash == NULL) || (hash->size == 0) || (key == NULL))
return(NULL);
hashValue = xmlHashValue(hash->randomSeed, key, key2, key3, NULL);
entry = xmlHashFindEntry(hash, key, key2, key3, hashValue, &found);
if (found)
return(entry->payload);
return(NULL);
}
/**
* xmlHashQLookup3:
* @hash: hash table
* @prefix: first prefix
* @name: first local name
* @prefix2: second prefix
* @name2: second local name
* @prefix3: third prefix
* @name3: third local name
*
* Find the payload specified by the QNames tuple.
*
* Returns a pointer to the payload or NULL if no entry was found.
*/
ATTRIBUTE_NO_SANITIZE_INTEGER
void *
xmlHashQLookup3(xmlHashTablePtr hash,
const xmlChar *prefix, const xmlChar *name,
const xmlChar *prefix2, const xmlChar *name2,
const xmlChar *prefix3, const xmlChar *name3) {
const xmlHashEntry *entry;
unsigned hashValue, mask, pos, displ;
if ((hash == NULL) || (hash->size == 0) || (name == NULL))
return(NULL);
hashValue = xmlHashQNameValue(hash->randomSeed, prefix, name, prefix2,
name2, prefix3, name3);
mask = hash->size - 1;
pos = hashValue & mask;
entry = &hash->table[pos];
if (entry->hashValue != 0) {
displ = 0;
hashValue |= MAX_HASH_SIZE;
do {
if ((hashValue == entry->hashValue) &&
(xmlStrQEqual(prefix, name, entry->key)) &&
(xmlStrQEqual(prefix2, name2, entry->key2)) &&
(xmlStrQEqual(prefix3, name3, entry->key3)))
return(entry->payload);
displ++;
pos++;
entry++;
if ((pos & mask) == 0)
entry = hash->table;
} while ((entry->hashValue != 0) &&
(((pos - entry->hashValue) & mask) >= displ));
}
return(NULL);
}
typedef struct {
xmlHashScanner scan;
void *data;
} stubData;
static void
stubHashScannerFull(void *payload, void *data, const xmlChar *key,
const xmlChar *key2 ATTRIBUTE_UNUSED,
const xmlChar *key3 ATTRIBUTE_UNUSED) {
stubData *sdata = (stubData *) data;
sdata->scan(payload, sdata->data, key);
}
/**
* xmlHashScan:
* @hash: hash table
* @scan: scanner function for items in the hash
* @data: extra data passed to @scan
*
* Scan the hash @table and apply @scan to each value.
*/
void
xmlHashScan(xmlHashTablePtr hash, xmlHashScanner scan, void *data) {
stubData sdata;
sdata.data = data;
sdata.scan = scan;
xmlHashScanFull(hash, stubHashScannerFull, &sdata);
}
/**
* xmlHashScanFull:
* @hash: hash table
* @scan: scanner function for items in the hash
* @data: extra data passed to @scan
*
* Scan the hash @table and apply @scan to each value.
*/
void
xmlHashScanFull(xmlHashTablePtr hash, xmlHashScannerFull scan, void *data) {
const xmlHashEntry *entry, *end;
xmlHashEntry old;
unsigned i;
if ((hash == NULL) || (hash->size == 0) || (scan == NULL))
return;
/*
* We must handle the case that a scanned entry is removed when executing
* the callback (xmlCleanSpecialAttr and possibly other places).
*
* Find the start of a probe sequence to avoid scanning entries twice if
* a deletion happens.
*/
entry = hash->table;
end = &hash->table[hash->size];
while (entry->hashValue != 0) {
if (++entry >= end)
entry = hash->table;
}
for (i = 0; i < hash->size; i++) {
if ((entry->hashValue != 0) && (entry->payload != NULL)) {
/*
* Make sure to rescan after a possible deletion.
*/
do {
old = *entry;
scan(entry->payload, data, entry->key, entry->key2, entry->key3);
} while ((entry->hashValue != 0) &&
(entry->payload != NULL) &&
((entry->key != old.key) ||
(entry->key2 != old.key2) ||
(entry->key3 != old.key3)));
}
if (++entry >= end)
entry = hash->table;
}
}
/**
* xmlHashScan3:
* @hash: hash table
* @key: first string key or NULL
* @key2: second string key or NULL
* @key3: third string key or NULL
* @scan: scanner function for items in the hash
* @data: extra data passed to @scan
*
* Scan the hash @table and apply @scan to each value matching
* (@key, @key2, @key3) tuple. If one of the keys is null,
* the comparison is considered to match.
*/
void
xmlHashScan3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
xmlHashScanner scan, void *data) {
stubData sdata;
sdata.data = data;
sdata.scan = scan;
xmlHashScanFull3(hash, key, key2, key3, stubHashScannerFull, &sdata);
}
/**
* xmlHashScanFull3:
* @hash: hash table
* @key: first string key or NULL
* @key2: second string key or NULL
* @key3: third string key or NULL
* @scan: scanner function for items in the hash
* @data: extra data passed to @scan
*
* Scan the hash @table and apply @scan to each value matching
* (@key, @key2, @key3) tuple. If one of the keys is null,
* the comparison is considered to match.
*/
void
xmlHashScanFull3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
xmlHashScannerFull scan, void *data) {
const xmlHashEntry *entry, *end;
xmlHashEntry old;
unsigned i;
if ((hash == NULL) || (hash->size == 0) || (scan == NULL))
return;
/*
* We must handle the case that a scanned entry is removed when executing
* the callback (xmlCleanSpecialAttr and possibly other places).
*
* Find the start of a probe sequence to avoid scanning entries twice if
* a deletion happens.
*/
entry = hash->table;
end = &hash->table[hash->size];
while (entry->hashValue != 0) {
if (++entry >= end)
entry = hash->table;
}
for (i = 0; i < hash->size; i++) {
if ((entry->hashValue != 0) && (entry->payload != NULL)) {
/*
* Make sure to rescan after a possible deletion.
*/
do {
if (((key != NULL) && (strcmp((const char *) key,
(const char *) entry->key) != 0)) ||
((key2 != NULL) && (!xmlFastStrEqual(key2, entry->key2))) ||
((key3 != NULL) && (!xmlFastStrEqual(key3, entry->key3))))
break;
old = *entry;
scan(entry->payload, data, entry->key, entry->key2, entry->key3);
} while ((entry->hashValue != 0) &&
(entry->payload != NULL) &&
((entry->key != old.key) ||
(entry->key2 != old.key2) ||
(entry->key3 != old.key3)));
}
if (++entry >= end)
entry = hash->table;
}
}
/*
* xmlHashCopySafe:
* @hash: hash table
* @copyFunc: copier function for items in the hash
* @deallocFunc: deallocation function in case of errors
*
* Copy the hash table using @copyFunc to copy payloads.
*
* Available since 2.13.0.
*
* Returns the new table or NULL if a memory allocation failed.
*/
xmlHashTablePtr
xmlHashCopySafe(xmlHashTablePtr hash, xmlHashCopier copyFunc,
xmlHashDeallocator deallocFunc) {
const xmlHashEntry *entry, *end;
xmlHashTablePtr ret;
if ((hash == NULL) || (copyFunc == NULL))
return(NULL);
ret = xmlHashCreate(hash->size);
if (ret == NULL)
return(NULL);
if (hash->size == 0)
return(ret);
end = &hash->table[hash->size];
for (entry = hash->table; entry < end; entry++) {
if (entry->hashValue != 0) {
void *copy;
copy = copyFunc(entry->payload, entry->key);
if (copy == NULL)
goto error;
if (xmlHashAdd3(ret, entry->key, entry->key2, entry->key3,
copy) <= 0) {
if (deallocFunc != NULL)
deallocFunc(copy, entry->key);
goto error;
}
}
}
return(ret);
error:
xmlHashFree(ret, deallocFunc);
return(NULL);
}
/*
* xmlHashCopy:
* @hash: hash table
* @copy: copier function for items in the hash
*
* DEPRECATED: Leaks memory in error case.
*
* Copy the hash table using @copy to copy payloads.
*
* Returns the new table or NULL if a memory allocation failed.
*/
xmlHashTablePtr
xmlHashCopy(xmlHashTablePtr hash, xmlHashCopier copy) {
return(xmlHashCopySafe(hash, copy, NULL));
}
/**
* xmlHashSize:
* @hash: hash table
*
* Query the number of elements in the hash table.
*
* Returns the number of elements in the hash table or
* -1 in case of error.
*/
int
xmlHashSize(xmlHashTablePtr hash) {
if (hash == NULL)
return(-1);
return(hash->nbElems);
}
/**
* xmlHashRemoveEntry:
* @hash: hash table
* @key: string key
* @dealloc: deallocator function for removed item or NULL
*
* Find the entry specified by the @key and remove it from the hash table.
* Payload will be freed with @dealloc.
*
* Returns 0 on success and -1 if no entry was found.
*/
int xmlHashRemoveEntry(xmlHashTablePtr hash, const xmlChar *key,
xmlHashDeallocator dealloc) {
return(xmlHashRemoveEntry3(hash, key, NULL, NULL, dealloc));
}
/**
* xmlHashRemoveEntry2:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @dealloc: deallocator function for removed item or NULL
*
* Remove an entry with two strings as key.
*
* See xmlHashRemoveEntry.
*
* Returns 0 on success and -1 in case of error.
*/
int
xmlHashRemoveEntry2(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, xmlHashDeallocator dealloc) {
return(xmlHashRemoveEntry3(hash, key, key2, NULL, dealloc));
}
/**
* xmlHashRemoveEntry3:
* @hash: hash table
* @key: first string key
* @key2: second string key
* @key3: third string key
* @dealloc: deallocator function for removed item or NULL
*
* Remove an entry with three strings as key.
*
* See xmlHashRemoveEntry.
*
* Returns 0 on success and -1 in case of error.
*/
ATTRIBUTE_NO_SANITIZE_INTEGER
int
xmlHashRemoveEntry3(xmlHashTablePtr hash, const xmlChar *key,
const xmlChar *key2, const xmlChar *key3,
xmlHashDeallocator dealloc) {
xmlHashEntry *entry, *cur, *next;
unsigned hashValue, mask, pos, nextpos;
int found;
if ((hash == NULL) || (hash->size == 0) || (key == NULL))
return(-1);
hashValue = xmlHashValue(hash->randomSeed, key, key2, key3, NULL);
entry = xmlHashFindEntry(hash, key, key2, key3, hashValue, &found);
if (!found)
return(-1);
if ((dealloc != NULL) && (entry->payload != NULL))
dealloc(entry->payload, entry->key);
if (hash->dict == NULL) {
if (entry->key)
xmlFree(entry->key);
if (entry->key2)
xmlFree(entry->key2);
if (entry->key3)
xmlFree(entry->key3);
}
/*
* Find end of probe sequence. Entries at their initial probe
* position start a new sequence.
*/
mask = hash->size - 1;
pos = entry - hash->table;
cur = entry;
while (1) {
nextpos = pos + 1;
next = cur + 1;
if ((nextpos & mask) == 0)
next = hash->table;
if ((next->hashValue == 0) ||
(((next->hashValue - nextpos) & mask) == 0))
break;
cur = next;
pos = nextpos;
}
/*
* Backward shift
*/
next = entry + 1;
if (cur < entry) {
xmlHashEntry *end = &hash->table[hash->size];
memmove(entry, next, (char *) end - (char *) next);
entry = hash->table;
end[-1] = *entry;
next = entry + 1;
}
memmove(entry, next, (char *) cur - (char *) entry);
/*
* Update entry
*/
cur->hashValue = 0;
hash->nbElems--;
return(0);
}