danielk1977 | 075c23a | 2008-09-01 18:34:20 +0000 | [diff] [blame] | 1 | /* |
| 2 | ** 2008 September 1 |
| 3 | ** |
| 4 | ** The author disclaims copyright to this source code. In place of |
| 5 | ** a legal notice, here is a blessing: |
| 6 | ** |
| 7 | ** May you do good and not evil. |
| 8 | ** May you find forgiveness for yourself and forgive others. |
| 9 | ** May you share freely, never taking more than you give. |
| 10 | ** |
| 11 | ************************************************************************* |
| 12 | ** |
| 13 | ** The code in this file contains sample implementations of the |
| 14 | ** sqlite3_wsd_init() and sqlite3_wsd_find() functions required if the |
| 15 | ** SQLITE_OMIT_WSD symbol is defined at build time. |
| 16 | ** |
drh | 18472fa | 2008-10-07 15:25:48 +0000 | [diff] [blame] | 17 | ** $Id: test_wsd.c,v 1.3 2008/10/07 15:25:49 drh Exp $ |
danielk1977 | 075c23a | 2008-09-01 18:34:20 +0000 | [diff] [blame] | 18 | */ |
| 19 | |
| 20 | #if defined(SQLITE_OMIT_WSD) && defined(SQLITE_TEST) |
| 21 | |
| 22 | #include "sqliteInt.h" |
| 23 | |
| 24 | #define PLS_HASHSIZE 43 |
| 25 | |
| 26 | typedef struct ProcessLocalStorage ProcessLocalStorage; |
| 27 | typedef struct ProcessLocalVar ProcessLocalVar; |
| 28 | |
| 29 | struct ProcessLocalStorage { |
| 30 | ProcessLocalVar *aData[PLS_HASHSIZE]; |
| 31 | int nFree; |
| 32 | u8 *pFree; |
| 33 | }; |
| 34 | |
| 35 | struct ProcessLocalVar { |
| 36 | void *pKey; |
| 37 | ProcessLocalVar *pNext; |
| 38 | }; |
| 39 | |
| 40 | static ProcessLocalStorage *pGlobal = 0; |
| 41 | |
| 42 | int sqlite3_wsd_init(int N, int J){ |
| 43 | if( !pGlobal ){ |
| 44 | int nMalloc = N + sizeof(ProcessLocalStorage) + J*sizeof(ProcessLocalVar); |
| 45 | pGlobal = (ProcessLocalStorage *)malloc(nMalloc); |
| 46 | if( pGlobal ){ |
| 47 | memset(pGlobal, 0, sizeof(ProcessLocalStorage)); |
| 48 | pGlobal->nFree = nMalloc - sizeof(ProcessLocalStorage); |
| 49 | pGlobal->pFree = (u8 *)&pGlobal[1]; |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | return pGlobal ? SQLITE_OK : SQLITE_NOMEM; |
| 54 | } |
| 55 | |
| 56 | void *sqlite3_wsd_find(void *K, int L){ |
| 57 | int i; |
| 58 | int iHash = 0; |
| 59 | ProcessLocalVar *pVar; |
| 60 | |
| 61 | /* Calculate a hash of K */ |
| 62 | for(i=0; i<sizeof(void*); i++){ |
danielk1977 | a8f83bf | 2008-09-02 16:22:28 +0000 | [diff] [blame] | 63 | iHash = (iHash<<3) + ((unsigned char *)&K)[i]; |
danielk1977 | 075c23a | 2008-09-01 18:34:20 +0000 | [diff] [blame] | 64 | } |
| 65 | iHash = iHash%PLS_HASHSIZE; |
| 66 | |
| 67 | /* Search the hash table for K. */ |
| 68 | for(pVar=pGlobal->aData[iHash]; pVar && pVar->pKey!=K; pVar=pVar->pNext); |
| 69 | |
| 70 | /* If no entry for K was found, create and populate a new one. */ |
| 71 | if( !pVar ){ |
| 72 | int nByte = (sizeof(ProcessLocalVar) + L + 7)&~7; |
| 73 | assert( pGlobal->nFree>=nByte ); |
| 74 | pVar = (ProcessLocalVar *)pGlobal->pFree; |
| 75 | pVar->pKey = K; |
| 76 | pVar->pNext = pGlobal->aData[iHash]; |
| 77 | pGlobal->aData[iHash] = pVar; |
| 78 | pGlobal->nFree -= nByte; |
| 79 | pGlobal->pFree += nByte; |
| 80 | memcpy(&pVar[1], K, L); |
| 81 | } |
| 82 | |
| 83 | return (void *)&pVar[1]; |
| 84 | } |
| 85 | |
| 86 | #endif |