1 /* 2 ** 2008 June 18 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 ** This module implements the sqlite3_status() interface and related 14 ** functionality. 15 */ 16 #include "sqliteInt.h" 17 #include "vdbeInt.h" 18 19 /* 20 ** Variables in which to record status information. 21 */ 22 typedef struct sqlite3StatType sqlite3StatType; 23 static SQLITE_WSD struct sqlite3StatType { 24 int nowValue[10]; /* Current value */ 25 int mxValue[10]; /* Maximum value */ 26 } sqlite3Stat = { {0,}, {0,} }; 27 28 29 /* The "wsdStat" macro will resolve to the status information 30 ** state vector. If writable static data is unsupported on the target, 31 ** we have to locate the state vector at run-time. In the more common 32 ** case where writable static data is supported, wsdStat can refer directly 33 ** to the "sqlite3Stat" state vector declared above. 34 */ 35 #ifdef SQLITE_OMIT_WSD 36 # define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat) 37 # define wsdStat x[0] 38 #else 39 # define wsdStatInit 40 # define wsdStat sqlite3Stat 41 #endif 42 43 /* 44 ** Return the current value of a status parameter. 45 */ 46 int sqlite3StatusValue(int op){ 47 wsdStatInit; 48 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 49 return wsdStat.nowValue[op]; 50 } 51 52 /* 53 ** Add N to the value of a status record. It is assumed that the 54 ** caller holds appropriate locks. 55 */ 56 void sqlite3StatusAdd(int op, int N){ 57 wsdStatInit; 58 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 59 wsdStat.nowValue[op] += N; 60 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){ 61 wsdStat.mxValue[op] = wsdStat.nowValue[op]; 62 } 63 } 64 65 /* 66 ** Set the value of a status to X. 67 */ 68 void sqlite3StatusSet(int op, int X){ 69 wsdStatInit; 70 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 71 wsdStat.nowValue[op] = X; 72 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){ 73 wsdStat.mxValue[op] = wsdStat.nowValue[op]; 74 } 75 } 76 77 /* 78 ** Query status information. 79 ** 80 ** This implementation assumes that reading or writing an aligned 81 ** 32-bit integer is an atomic operation. If that assumption is not true, 82 ** then this routine is not threadsafe. 83 */ 84 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){ 85 wsdStatInit; 86 if( op<0 || op>=ArraySize(wsdStat.nowValue) ){ 87 return SQLITE_MISUSE_BKPT; 88 } 89 #ifdef SQLITE_ENABLE_API_ARMOR 90 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT; 91 #endif 92 *pCurrent = wsdStat.nowValue[op]; 93 *pHighwater = wsdStat.mxValue[op]; 94 if( resetFlag ){ 95 wsdStat.mxValue[op] = wsdStat.nowValue[op]; 96 } 97 return SQLITE_OK; 98 } 99 100 /* 101 ** Query status information for a single database connection 102 */ 103 int sqlite3_db_status( 104 sqlite3 *db, /* The database connection whose status is desired */ 105 int op, /* Status verb */ 106 int *pCurrent, /* Write current value here */ 107 int *pHighwater, /* Write high-water mark here */ 108 int resetFlag /* Reset high-water mark if true */ 109 ){ 110 int rc = SQLITE_OK; /* Return code */ 111 #ifdef SQLITE_ENABLE_API_ARMOR 112 if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){ 113 return SQLITE_MISUSE_BKPT; 114 } 115 #endif 116 sqlite3_mutex_enter(db->mutex); 117 switch( op ){ 118 case SQLITE_DBSTATUS_LOOKASIDE_USED: { 119 *pCurrent = db->lookaside.nOut; 120 *pHighwater = db->lookaside.mxOut; 121 if( resetFlag ){ 122 db->lookaside.mxOut = db->lookaside.nOut; 123 } 124 break; 125 } 126 127 case SQLITE_DBSTATUS_LOOKASIDE_HIT: 128 case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE: 129 case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: { 130 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT ); 131 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE ); 132 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL ); 133 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 ); 134 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 ); 135 *pCurrent = 0; 136 *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT]; 137 if( resetFlag ){ 138 db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0; 139 } 140 break; 141 } 142 143 /* 144 ** Return an approximation for the amount of memory currently used 145 ** by all pagers associated with the given database connection. The 146 ** highwater mark is meaningless and is returned as zero. 147 */ 148 case SQLITE_DBSTATUS_CACHE_USED: { 149 int totalUsed = 0; 150 int i; 151 sqlite3BtreeEnterAll(db); 152 for(i=0; i<db->nDb; i++){ 153 Btree *pBt = db->aDb[i].pBt; 154 if( pBt ){ 155 Pager *pPager = sqlite3BtreePager(pBt); 156 totalUsed += sqlite3PagerMemUsed(pPager); 157 } 158 } 159 sqlite3BtreeLeaveAll(db); 160 *pCurrent = totalUsed; 161 *pHighwater = 0; 162 break; 163 } 164 165 /* 166 ** *pCurrent gets an accurate estimate of the amount of memory used 167 ** to store the schema for all databases (main, temp, and any ATTACHed 168 ** databases. *pHighwater is set to zero. 169 */ 170 case SQLITE_DBSTATUS_SCHEMA_USED: { 171 int i; /* Used to iterate through schemas */ 172 int nByte = 0; /* Used to accumulate return value */ 173 174 sqlite3BtreeEnterAll(db); 175 db->pnBytesFreed = &nByte; 176 for(i=0; i<db->nDb; i++){ 177 Schema *pSchema = db->aDb[i].pSchema; 178 if( ALWAYS(pSchema!=0) ){ 179 HashElem *p; 180 181 nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * ( 182 pSchema->tblHash.count 183 + pSchema->trigHash.count 184 + pSchema->idxHash.count 185 + pSchema->fkeyHash.count 186 ); 187 nByte += sqlite3MallocSize(pSchema->tblHash.ht); 188 nByte += sqlite3MallocSize(pSchema->trigHash.ht); 189 nByte += sqlite3MallocSize(pSchema->idxHash.ht); 190 nByte += sqlite3MallocSize(pSchema->fkeyHash.ht); 191 192 for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){ 193 sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p)); 194 } 195 for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){ 196 sqlite3DeleteTable(db, (Table *)sqliteHashData(p)); 197 } 198 } 199 } 200 db->pnBytesFreed = 0; 201 sqlite3BtreeLeaveAll(db); 202 203 *pHighwater = 0; 204 *pCurrent = nByte; 205 break; 206 } 207 208 /* 209 ** *pCurrent gets an accurate estimate of the amount of memory used 210 ** to store all prepared statements. 211 ** *pHighwater is set to zero. 212 */ 213 case SQLITE_DBSTATUS_STMT_USED: { 214 struct Vdbe *pVdbe; /* Used to iterate through VMs */ 215 int nByte = 0; /* Used to accumulate return value */ 216 217 db->pnBytesFreed = &nByte; 218 for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){ 219 sqlite3VdbeClearObject(db, pVdbe); 220 sqlite3DbFree(db, pVdbe); 221 } 222 db->pnBytesFreed = 0; 223 224 *pHighwater = 0; /* IMP: R-64479-57858 */ 225 *pCurrent = nByte; 226 227 break; 228 } 229 230 /* 231 ** Set *pCurrent to the total cache hits or misses encountered by all 232 ** pagers the database handle is connected to. *pHighwater is always set 233 ** to zero. 234 */ 235 case SQLITE_DBSTATUS_CACHE_HIT: 236 case SQLITE_DBSTATUS_CACHE_MISS: 237 case SQLITE_DBSTATUS_CACHE_WRITE:{ 238 int i; 239 int nRet = 0; 240 assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 ); 241 assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 ); 242 243 for(i=0; i<db->nDb; i++){ 244 if( db->aDb[i].pBt ){ 245 Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt); 246 sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet); 247 } 248 } 249 *pHighwater = 0; /* IMP: R-42420-56072 */ 250 /* IMP: R-54100-20147 */ 251 /* IMP: R-29431-39229 */ 252 *pCurrent = nRet; 253 break; 254 } 255 256 /* Set *pCurrent to non-zero if there are unresolved deferred foreign 257 ** key constraints. Set *pCurrent to zero if all foreign key constraints 258 ** have been satisfied. The *pHighwater is always set to zero. 259 */ 260 case SQLITE_DBSTATUS_DEFERRED_FKS: { 261 *pHighwater = 0; /* IMP: R-11967-56545 */ 262 *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0; 263 break; 264 } 265 266 default: { 267 rc = SQLITE_ERROR; 268 } 269 } 270 sqlite3_mutex_leave(db->mutex); 271 return rc; 272 } 273