/* ** 2008 September 1 ** ** 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. ** ************************************************************************* ** ** The code in this file contains sample implementations of the ** sqlite3_wsd_init() and sqlite3_wsd_find() functions required if the ** SQLITE_OMIT_WSD symbol is defined at build time. */ #if defined(SQLITE_OMIT_WSD) && defined(SQLITE_TEST) #include "sqliteInt.h" #define PLS_HASHSIZE 43 typedef struct ProcessLocalStorage ProcessLocalStorage; typedef struct ProcessLocalVar ProcessLocalVar; struct ProcessLocalStorage { ProcessLocalVar *aData[PLS_HASHSIZE]; int nFree; u8 *pFree; }; struct ProcessLocalVar { void *pKey; ProcessLocalVar *pNext; }; static ProcessLocalStorage *pGlobal = 0; int sqlite3_wsd_init(int N, int J){ if( !pGlobal ){ int nMalloc = N + sizeof(ProcessLocalStorage) + J*sizeof(ProcessLocalVar); pGlobal = (ProcessLocalStorage *)malloc(nMalloc); if( pGlobal ){ memset(pGlobal, 0, sizeof(ProcessLocalStorage)); pGlobal->nFree = nMalloc - sizeof(ProcessLocalStorage); pGlobal->pFree = (u8 *)&pGlobal[1]; } } return pGlobal ? SQLITE_OK : SQLITE_NOMEM; } void *sqlite3_wsd_find(void *K, int L){ int i; int iHash = 0; ProcessLocalVar *pVar; /* Calculate a hash of K */ for(i=0; i<sizeof(void*); i++){ iHash = (iHash<<3) + ((unsigned char *)&K)[i]; } iHash = iHash%PLS_HASHSIZE; /* Search the hash table for K. */ for(pVar=pGlobal->aData[iHash]; pVar && pVar->pKey!=K; pVar=pVar->pNext); /* If no entry for K was found, create and populate a new one. */ if( !pVar ){ int nByte = ROUND8(sizeof(ProcessLocalVar) + L); assert( pGlobal->nFree>=nByte ); pVar = (ProcessLocalVar *)pGlobal->pFree; pVar->pKey = K; pVar->pNext = pGlobal->aData[iHash]; pGlobal->aData[iHash] = pVar; pGlobal->nFree -= nByte; pGlobal->pFree += nByte; memcpy(&pVar[1], K, L); } return (void *)&pVar[1]; } #endif