000001 /*
000002 ** 2008 June 18
000003 **
000004 ** The author disclaims copyright to this source code. In place of
000005 ** a legal notice, here is a blessing:
000006 **
000007 ** May you do good and not evil.
000008 ** May you find forgiveness for yourself and forgive others.
000009 ** May you share freely, never taking more than you give.
000010 **
000011 *************************************************************************
000012 **
000013 ** This module implements the sqlite3_status() interface and related
000014 ** functionality.
000015 */
000016 #include "sqliteInt.h"
000017 #include "vdbeInt.h"
000018
000019 /*
000020 ** Variables in which to record status information.
000021 */
000022 #if SQLITE_PTRSIZE>4
000023 typedef sqlite3_int64 sqlite3StatValueType;
000024 #else
000025 typedef u32 sqlite3StatValueType;
000026 #endif
000027 typedef struct sqlite3StatType sqlite3StatType;
000028 static SQLITE_WSD struct sqlite3StatType {
000029 sqlite3StatValueType nowValue[10]; /* Current value */
000030 sqlite3StatValueType mxValue[10]; /* Maximum value */
000031 } sqlite3Stat = { {0,}, {0,} };
000032
000033 /*
000034 ** Elements of sqlite3Stat[] are protected by either the memory allocator
000035 ** mutex, or by the pcache1 mutex. The following array determines which.
000036 */
000037 static const char statMutex[] = {
000038 0, /* SQLITE_STATUS_MEMORY_USED */
000039 1, /* SQLITE_STATUS_PAGECACHE_USED */
000040 1, /* SQLITE_STATUS_PAGECACHE_OVERFLOW */
000041 0, /* SQLITE_STATUS_SCRATCH_USED */
000042 0, /* SQLITE_STATUS_SCRATCH_OVERFLOW */
000043 0, /* SQLITE_STATUS_MALLOC_SIZE */
000044 0, /* SQLITE_STATUS_PARSER_STACK */
000045 1, /* SQLITE_STATUS_PAGECACHE_SIZE */
000046 0, /* SQLITE_STATUS_SCRATCH_SIZE */
000047 0, /* SQLITE_STATUS_MALLOC_COUNT */
000048 };
000049
000050
000051 /* The "wsdStat" macro will resolve to the status information
000052 ** state vector. If writable static data is unsupported on the target,
000053 ** we have to locate the state vector at run-time. In the more common
000054 ** case where writable static data is supported, wsdStat can refer directly
000055 ** to the "sqlite3Stat" state vector declared above.
000056 */
000057 #ifdef SQLITE_OMIT_WSD
000058 # define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
000059 # define wsdStat x[0]
000060 #else
000061 # define wsdStatInit
000062 # define wsdStat sqlite3Stat
000063 #endif
000064
000065 /*
000066 ** Return the current value of a status parameter. The caller must
000067 ** be holding the appropriate mutex.
000068 */
000069 sqlite3_int64 sqlite3StatusValue(int op){
000070 wsdStatInit;
000071 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000072 assert( op>=0 && op<ArraySize(statMutex) );
000073 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000074 : sqlite3MallocMutex()) );
000075 return wsdStat.nowValue[op];
000076 }
000077
000078 /*
000079 ** Add N to the value of a status record. The caller must hold the
000080 ** appropriate mutex. (Locking is checked by assert()).
000081 **
000082 ** The StatusUp() routine can accept positive or negative values for N.
000083 ** The value of N is added to the current status value and the high-water
000084 ** mark is adjusted if necessary.
000085 **
000086 ** The StatusDown() routine lowers the current value by N. The highwater
000087 ** mark is unchanged. N must be non-negative for StatusDown().
000088 */
000089 void sqlite3StatusUp(int op, int N){
000090 wsdStatInit;
000091 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000092 assert( op>=0 && op<ArraySize(statMutex) );
000093 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000094 : sqlite3MallocMutex()) );
000095 wsdStat.nowValue[op] += N;
000096 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
000097 wsdStat.mxValue[op] = wsdStat.nowValue[op];
000098 }
000099 }
000100 void sqlite3StatusDown(int op, int N){
000101 wsdStatInit;
000102 assert( N>=0 );
000103 assert( op>=0 && op<ArraySize(statMutex) );
000104 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000105 : sqlite3MallocMutex()) );
000106 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000107 wsdStat.nowValue[op] -= N;
000108 }
000109
000110 /*
000111 ** Adjust the highwater mark if necessary.
000112 ** The caller must hold the appropriate mutex.
000113 */
000114 void sqlite3StatusHighwater(int op, int X){
000115 sqlite3StatValueType newValue;
000116 wsdStatInit;
000117 assert( X>=0 );
000118 newValue = (sqlite3StatValueType)X;
000119 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000120 assert( op>=0 && op<ArraySize(statMutex) );
000121 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000122 : sqlite3MallocMutex()) );
000123 assert( op==SQLITE_STATUS_MALLOC_SIZE
000124 || op==SQLITE_STATUS_PAGECACHE_SIZE
000125 || op==SQLITE_STATUS_SCRATCH_SIZE
000126 || op==SQLITE_STATUS_PARSER_STACK );
000127 if( newValue>wsdStat.mxValue[op] ){
000128 wsdStat.mxValue[op] = newValue;
000129 }
000130 }
000131
000132 /*
000133 ** Query status information.
000134 */
000135 int sqlite3_status64(
000136 int op,
000137 sqlite3_int64 *pCurrent,
000138 sqlite3_int64 *pHighwater,
000139 int resetFlag
000140 ){
000141 sqlite3_mutex *pMutex;
000142 wsdStatInit;
000143 if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
000144 return SQLITE_MISUSE_BKPT;
000145 }
000146 #ifdef SQLITE_ENABLE_API_ARMOR
000147 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
000148 #endif
000149 pMutex = statMutex[op] ? sqlite3Pcache1Mutex() : sqlite3MallocMutex();
000150 sqlite3_mutex_enter(pMutex);
000151 *pCurrent = wsdStat.nowValue[op];
000152 *pHighwater = wsdStat.mxValue[op];
000153 if( resetFlag ){
000154 wsdStat.mxValue[op] = wsdStat.nowValue[op];
000155 }
000156 sqlite3_mutex_leave(pMutex);
000157 (void)pMutex; /* Prevent warning when SQLITE_THREADSAFE=0 */
000158 return SQLITE_OK;
000159 }
000160 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
000161 sqlite3_int64 iCur = 0, iHwtr = 0;
000162 int rc;
000163 #ifdef SQLITE_ENABLE_API_ARMOR
000164 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
000165 #endif
000166 rc = sqlite3_status64(op, &iCur, &iHwtr, resetFlag);
000167 if( rc==0 ){
000168 *pCurrent = (int)iCur;
000169 *pHighwater = (int)iHwtr;
000170 }
000171 return rc;
000172 }
000173
000174 /*
000175 ** Query status information for a single database connection
000176 */
000177 int sqlite3_db_status(
000178 sqlite3 *db, /* The database connection whose status is desired */
000179 int op, /* Status verb */
000180 int *pCurrent, /* Write current value here */
000181 int *pHighwater, /* Write high-water mark here */
000182 int resetFlag /* Reset high-water mark if true */
000183 ){
000184 int rc = SQLITE_OK; /* Return code */
000185 #ifdef SQLITE_ENABLE_API_ARMOR
000186 if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){
000187 return SQLITE_MISUSE_BKPT;
000188 }
000189 #endif
000190 sqlite3_mutex_enter(db->mutex);
000191 switch( op ){
000192 case SQLITE_DBSTATUS_LOOKASIDE_USED: {
000193 *pCurrent = db->lookaside.nOut;
000194 *pHighwater = db->lookaside.mxOut;
000195 if( resetFlag ){
000196 db->lookaside.mxOut = db->lookaside.nOut;
000197 }
000198 break;
000199 }
000200
000201 case SQLITE_DBSTATUS_LOOKASIDE_HIT:
000202 case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
000203 case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
000204 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
000205 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
000206 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
000207 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
000208 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
000209 *pCurrent = 0;
000210 *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
000211 if( resetFlag ){
000212 db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
000213 }
000214 break;
000215 }
000216
000217 /*
000218 ** Return an approximation for the amount of memory currently used
000219 ** by all pagers associated with the given database connection. The
000220 ** highwater mark is meaningless and is returned as zero.
000221 */
000222 case SQLITE_DBSTATUS_CACHE_USED_SHARED:
000223 case SQLITE_DBSTATUS_CACHE_USED: {
000224 int totalUsed = 0;
000225 int i;
000226 sqlite3BtreeEnterAll(db);
000227 for(i=0; i<db->nDb; i++){
000228 Btree *pBt = db->aDb[i].pBt;
000229 if( pBt ){
000230 Pager *pPager = sqlite3BtreePager(pBt);
000231 int nByte = sqlite3PagerMemUsed(pPager);
000232 if( op==SQLITE_DBSTATUS_CACHE_USED_SHARED ){
000233 nByte = nByte / sqlite3BtreeConnectionCount(pBt);
000234 }
000235 totalUsed += nByte;
000236 }
000237 }
000238 sqlite3BtreeLeaveAll(db);
000239 *pCurrent = totalUsed;
000240 *pHighwater = 0;
000241 break;
000242 }
000243
000244 /*
000245 ** *pCurrent gets an accurate estimate of the amount of memory used
000246 ** to store the schema for all databases (main, temp, and any ATTACHed
000247 ** databases. *pHighwater is set to zero.
000248 */
000249 case SQLITE_DBSTATUS_SCHEMA_USED: {
000250 int i; /* Used to iterate through schemas */
000251 int nByte = 0; /* Used to accumulate return value */
000252
000253 sqlite3BtreeEnterAll(db);
000254 db->pnBytesFreed = &nByte;
000255 for(i=0; i<db->nDb; i++){
000256 Schema *pSchema = db->aDb[i].pSchema;
000257 if( ALWAYS(pSchema!=0) ){
000258 HashElem *p;
000259
000260 nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
000261 pSchema->tblHash.count
000262 + pSchema->trigHash.count
000263 + pSchema->idxHash.count
000264 + pSchema->fkeyHash.count
000265 );
000266 nByte += sqlite3_msize(pSchema->tblHash.ht);
000267 nByte += sqlite3_msize(pSchema->trigHash.ht);
000268 nByte += sqlite3_msize(pSchema->idxHash.ht);
000269 nByte += sqlite3_msize(pSchema->fkeyHash.ht);
000270
000271 for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
000272 sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
000273 }
000274 for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
000275 sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
000276 }
000277 }
000278 }
000279 db->pnBytesFreed = 0;
000280 sqlite3BtreeLeaveAll(db);
000281
000282 *pHighwater = 0;
000283 *pCurrent = nByte;
000284 break;
000285 }
000286
000287 /*
000288 ** *pCurrent gets an accurate estimate of the amount of memory used
000289 ** to store all prepared statements.
000290 ** *pHighwater is set to zero.
000291 */
000292 case SQLITE_DBSTATUS_STMT_USED: {
000293 struct Vdbe *pVdbe; /* Used to iterate through VMs */
000294 int nByte = 0; /* Used to accumulate return value */
000295
000296 db->pnBytesFreed = &nByte;
000297 for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
000298 sqlite3VdbeClearObject(db, pVdbe);
000299 sqlite3DbFree(db, pVdbe);
000300 }
000301 db->pnBytesFreed = 0;
000302
000303 *pHighwater = 0; /* IMP: R-64479-57858 */
000304 *pCurrent = nByte;
000305
000306 break;
000307 }
000308
000309 /*
000310 ** Set *pCurrent to the total cache hits or misses encountered by all
000311 ** pagers the database handle is connected to. *pHighwater is always set
000312 ** to zero.
000313 */
000314 case SQLITE_DBSTATUS_CACHE_HIT:
000315 case SQLITE_DBSTATUS_CACHE_MISS:
000316 case SQLITE_DBSTATUS_CACHE_WRITE:{
000317 int i;
000318 int nRet = 0;
000319 assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
000320 assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );
000321
000322 for(i=0; i<db->nDb; i++){
000323 if( db->aDb[i].pBt ){
000324 Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
000325 sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
000326 }
000327 }
000328 *pHighwater = 0; /* IMP: R-42420-56072 */
000329 /* IMP: R-54100-20147 */
000330 /* IMP: R-29431-39229 */
000331 *pCurrent = nRet;
000332 break;
000333 }
000334
000335 /* Set *pCurrent to non-zero if there are unresolved deferred foreign
000336 ** key constraints. Set *pCurrent to zero if all foreign key constraints
000337 ** have been satisfied. The *pHighwater is always set to zero.
000338 */
000339 case SQLITE_DBSTATUS_DEFERRED_FKS: {
000340 *pHighwater = 0; /* IMP: R-11967-56545 */
000341 *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
000342 break;
000343 }
000344
000345 default: {
000346 rc = SQLITE_ERROR;
000347 }
000348 }
000349 sqlite3_mutex_leave(db->mutex);
000350 return rc;
000351 }