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-rw-r--r--chromium/third_party/sqlite/sqlite-src-3240000/src/hash.c269
1 files changed, 0 insertions, 269 deletions
diff --git a/chromium/third_party/sqlite/sqlite-src-3240000/src/hash.c b/chromium/third_party/sqlite/sqlite-src-3240000/src/hash.c
deleted file mode 100644
index 79bb85ac01d..00000000000
--- a/chromium/third_party/sqlite/sqlite-src-3240000/src/hash.c
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@@ -1,269 +0,0 @@
-/*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code. In place of
-** a legal notice, here is a blessing:
-**
-** May you do good and not evil.
-** May you find forgiveness for yourself and forgive others.
-** May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the implementation of generic hash-tables
-** used in SQLite.
-*/
-#include "sqliteInt.h"
-#include <assert.h>
-
-/* Turn bulk memory into a hash table object by initializing the
-** fields of the Hash structure.
-**
-** "pNew" is a pointer to the hash table that is to be initialized.
-*/
-void sqlite3HashInit(Hash *pNew){
- assert( pNew!=0 );
- pNew->first = 0;
- pNew->count = 0;
- pNew->htsize = 0;
- pNew->ht = 0;
-}
-
-/* Remove all entries from a hash table. Reclaim all memory.
-** Call this routine to delete a hash table or to reset a hash table
-** to the empty state.
-*/
-void sqlite3HashClear(Hash *pH){
- HashElem *elem; /* For looping over all elements of the table */
-
- assert( pH!=0 );
- elem = pH->first;
- pH->first = 0;
- sqlite3_free(pH->ht);
- pH->ht = 0;
- pH->htsize = 0;
- while( elem ){
- HashElem *next_elem = elem->next;
- sqlite3_free(elem);
- elem = next_elem;
- }
- pH->count = 0;
-}
-
-/*
-** The hashing function.
-*/
-static unsigned int strHash(const char *z){
- unsigned int h = 0;
- unsigned char c;
- while( (c = (unsigned char)*z++)!=0 ){ /*OPTIMIZATION-IF-TRUE*/
- /* Knuth multiplicative hashing. (Sorting & Searching, p. 510).
- ** 0x9e3779b1 is 2654435761 which is the closest prime number to
- ** (2**32)*golden_ratio, where golden_ratio = (sqrt(5) - 1)/2. */
- h += sqlite3UpperToLower[c];
- h *= 0x9e3779b1;
- }
- return h;
-}
-
-
-/* Link pNew element into the hash table pH. If pEntry!=0 then also
-** insert pNew into the pEntry hash bucket.
-*/
-static void insertElement(
- Hash *pH, /* The complete hash table */
- struct _ht *pEntry, /* The entry into which pNew is inserted */
- HashElem *pNew /* The element to be inserted */
-){
- HashElem *pHead; /* First element already in pEntry */
- if( pEntry ){
- pHead = pEntry->count ? pEntry->chain : 0;
- pEntry->count++;
- pEntry->chain = pNew;
- }else{
- pHead = 0;
- }
- if( pHead ){
- pNew->next = pHead;
- pNew->prev = pHead->prev;
- if( pHead->prev ){ pHead->prev->next = pNew; }
- else { pH->first = pNew; }
- pHead->prev = pNew;
- }else{
- pNew->next = pH->first;
- if( pH->first ){ pH->first->prev = pNew; }
- pNew->prev = 0;
- pH->first = pNew;
- }
-}
-
-
-/* Resize the hash table so that it cantains "new_size" buckets.
-**
-** The hash table might fail to resize if sqlite3_malloc() fails or
-** if the new size is the same as the prior size.
-** Return TRUE if the resize occurs and false if not.
-*/
-static int rehash(Hash *pH, unsigned int new_size){
- struct _ht *new_ht; /* The new hash table */
- HashElem *elem, *next_elem; /* For looping over existing elements */
-
-#if SQLITE_MALLOC_SOFT_LIMIT>0
- if( new_size*sizeof(struct _ht)>SQLITE_MALLOC_SOFT_LIMIT ){
- new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
- }
- if( new_size==pH->htsize ) return 0;
-#endif
-
- /* The inability to allocates space for a larger hash table is
- ** a performance hit but it is not a fatal error. So mark the
- ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of
- ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
- ** only zeroes the requested number of bytes whereas this module will
- ** use the actual amount of space allocated for the hash table (which
- ** may be larger than the requested amount).
- */
- sqlite3BeginBenignMalloc();
- new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
- sqlite3EndBenignMalloc();
-
- if( new_ht==0 ) return 0;
- sqlite3_free(pH->ht);
- pH->ht = new_ht;
- pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
- memset(new_ht, 0, new_size*sizeof(struct _ht));
- for(elem=pH->first, pH->first=0; elem; elem = next_elem){
- unsigned int h = strHash(elem->pKey) % new_size;
- next_elem = elem->next;
- insertElement(pH, &new_ht[h], elem);
- }
- return 1;
-}
-
-/* This function (for internal use only) locates an element in an
-** hash table that matches the given key. If no element is found,
-** a pointer to a static null element with HashElem.data==0 is returned.
-** If pH is not NULL, then the hash for this key is written to *pH.
-*/
-static HashElem *findElementWithHash(
- const Hash *pH, /* The pH to be searched */
- const char *pKey, /* The key we are searching for */
- unsigned int *pHash /* Write the hash value here */
-){
- HashElem *elem; /* Used to loop thru the element list */
- int count; /* Number of elements left to test */
- unsigned int h; /* The computed hash */
- static HashElem nullElement = { 0, 0, 0, 0 };
-
- if( pH->ht ){ /*OPTIMIZATION-IF-TRUE*/
- struct _ht *pEntry;
- h = strHash(pKey) % pH->htsize;
- pEntry = &pH->ht[h];
- elem = pEntry->chain;
- count = pEntry->count;
- }else{
- h = 0;
- elem = pH->first;
- count = pH->count;
- }
- if( pHash ) *pHash = h;
- while( count-- ){
- assert( elem!=0 );
- if( sqlite3StrICmp(elem->pKey,pKey)==0 ){
- return elem;
- }
- elem = elem->next;
- }
- return &nullElement;
-}
-
-/* Remove a single entry from the hash table given a pointer to that
-** element and a hash on the element's key.
-*/
-static void removeElementGivenHash(
- Hash *pH, /* The pH containing "elem" */
- HashElem* elem, /* The element to be removed from the pH */
- unsigned int h /* Hash value for the element */
-){
- struct _ht *pEntry;
- if( elem->prev ){
- elem->prev->next = elem->next;
- }else{
- pH->first = elem->next;
- }
- if( elem->next ){
- elem->next->prev = elem->prev;
- }
- if( pH->ht ){
- pEntry = &pH->ht[h];
- if( pEntry->chain==elem ){
- pEntry->chain = elem->next;
- }
- pEntry->count--;
- assert( pEntry->count>=0 );
- }
- sqlite3_free( elem );
- pH->count--;
- if( pH->count==0 ){
- assert( pH->first==0 );
- assert( pH->count==0 );
- sqlite3HashClear(pH);
- }
-}
-
-/* Attempt to locate an element of the hash table pH with a key
-** that matches pKey. Return the data for this element if it is
-** found, or NULL if there is no match.
-*/
-void *sqlite3HashFind(const Hash *pH, const char *pKey){
- assert( pH!=0 );
- assert( pKey!=0 );
- return findElementWithHash(pH, pKey, 0)->data;
-}
-
-/* Insert an element into the hash table pH. The key is pKey
-** and the data is "data".
-**
-** If no element exists with a matching key, then a new
-** element is created and NULL is returned.
-**
-** If another element already exists with the same key, then the
-** new data replaces the old data and the old data is returned.
-** The key is not copied in this instance. If a malloc fails, then
-** the new data is returned and the hash table is unchanged.
-**
-** If the "data" parameter to this function is NULL, then the
-** element corresponding to "key" is removed from the hash table.
-*/
-void *sqlite3HashInsert(Hash *pH, const char *pKey, void *data){
- unsigned int h; /* the hash of the key modulo hash table size */
- HashElem *elem; /* Used to loop thru the element list */
- HashElem *new_elem; /* New element added to the pH */
-
- assert( pH!=0 );
- assert( pKey!=0 );
- elem = findElementWithHash(pH,pKey,&h);
- if( elem->data ){
- void *old_data = elem->data;
- if( data==0 ){
- removeElementGivenHash(pH,elem,h);
- }else{
- elem->data = data;
- elem->pKey = pKey;
- }
- return old_data;
- }
- if( data==0 ) return 0;
- new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
- if( new_elem==0 ) return data;
- new_elem->pKey = pKey;
- new_elem->data = data;
- pH->count++;
- if( pH->count>=10 && pH->count > 2*pH->htsize ){
- if( rehash(pH, pH->count*2) ){
- assert( pH->htsize>0 );
- h = strHash(pKey) % pH->htsize;
- }
- }
- insertElement(pH, pH->ht ? &pH->ht[h] : 0, new_elem);
- return 0;
-}
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