[sqlite] Remove obsolete reference version 3.8.7.4.

third_party/sqlite/sqlite-src-3080704/src/btmutex.c

Index: third_party/sqlite/sqlite-src-3080704/src/btmutex.c
diff --git a/third_party/sqlite/sqlite-src-3080704/src/btmutex.c b/third_party/sqlite/sqlite-src-3080704/src/btmutex.c
deleted file mode 100644
index f9fe5b3dde03c726191d361252bf29d724b1f50a..0000000000000000000000000000000000000000
--- a/third_party/sqlite/sqlite-src-3080704/src/btmutex.c
+++ /dev/null
@@ -1,300 +0,0 @@
-/*
-** 2007 August 27
-**
-** 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 file contains code used to implement mutexes on Btree objects.
-** This code really belongs in btree.c.  But btree.c is getting too
-** big and we want to break it down some.  This packaged seemed like
-** a good breakout.
-*/
-#include "btreeInt.h"
-#ifndef SQLITE_OMIT_SHARED_CACHE
-#if SQLITE_THREADSAFE
-
-/*
-** Obtain the BtShared mutex associated with B-Tree handle p. Also,
-** set BtShared.db to the database handle associated with p and the
-** p->locked boolean to true.
-*/
-static void lockBtreeMutex(Btree *p){
-  assert( p->locked==0 );
-  assert( sqlite3_mutex_notheld(p->pBt->mutex) );
-  assert( sqlite3_mutex_held(p->db->mutex) );
-
-  sqlite3_mutex_enter(p->pBt->mutex);
-  p->pBt->db = p->db;
-  p->locked = 1;
-}
-
-/*
-** Release the BtShared mutex associated with B-Tree handle p and
-** clear the p->locked boolean.
-*/
-static void SQLITE_NOINLINE unlockBtreeMutex(Btree *p){
-  BtShared *pBt = p->pBt;
-  assert( p->locked==1 );
-  assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( sqlite3_mutex_held(p->db->mutex) );
-  assert( p->db==pBt->db );
-
-  sqlite3_mutex_leave(pBt->mutex);
-  p->locked = 0;
-}
-
-/* Forward reference */
-static void SQLITE_NOINLINE btreeLockCarefully(Btree *p);
-
-/*
-** Enter a mutex on the given BTree object.
-**
-** If the object is not sharable, then no mutex is ever required
-** and this routine is a no-op.  The underlying mutex is non-recursive.
-** But we keep a reference count in Btree.wantToLock so the behavior
-** of this interface is recursive.
-**
-** To avoid deadlocks, multiple Btrees are locked in the same order
-** by all database connections.  The p->pNext is a list of other
-** Btrees belonging to the same database connection as the p Btree
-** which need to be locked after p.  If we cannot get a lock on
-** p, then first unlock all of the others on p->pNext, then wait
-** for the lock to become available on p, then relock all of the
-** subsequent Btrees that desire a lock.
-*/
-void sqlite3BtreeEnter(Btree *p){
-  /* Some basic sanity checking on the Btree.  The list of Btrees
-  ** connected by pNext and pPrev should be in sorted order by
-  ** Btree.pBt value. All elements of the list should belong to
-  ** the same connection. Only shared Btrees are on the list. */
-  assert( p->pNext==0 || p->pNext->pBt>p->pBt );
-  assert( p->pPrev==0 || p->pPrev->pBt<p->pBt );
-  assert( p->pNext==0 || p->pNext->db==p->db );
-  assert( p->pPrev==0 || p->pPrev->db==p->db );
-  assert( p->sharable || (p->pNext==0 && p->pPrev==0) );
-
-  /* Check for locking consistency */
-  assert( !p->locked || p->wantToLock>0 );
-  assert( p->sharable || p->wantToLock==0 );
-
-  /* We should already hold a lock on the database connection */
-  assert( sqlite3_mutex_held(p->db->mutex) );
-
-  /* Unless the database is sharable and unlocked, then BtShared.db
-  ** should already be set correctly. */
-  assert( (p->locked==0 && p->sharable) || p->pBt->db==p->db );
-
-  if( !p->sharable ) return;
-  p->wantToLock++;
-  if( p->locked ) return;
-  btreeLockCarefully(p);
-}
-
-/* This is a helper function for sqlite3BtreeLock(). By moving
-** complex, but seldom used logic, out of sqlite3BtreeLock() and
-** into this routine, we avoid unnecessary stack pointer changes
-** and thus help the sqlite3BtreeLock() routine to run much faster
-** in the common case.
-*/
-static void SQLITE_NOINLINE btreeLockCarefully(Btree *p){
-  Btree *pLater;
-
-  /* In most cases, we should be able to acquire the lock we
-  ** want without having to go through the ascending lock
-  ** procedure that follows.  Just be sure not to block.
-  */
-  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
-    p->pBt->db = p->db;
-    p->locked = 1;
-    return;
-  }
-
-  /* To avoid deadlock, first release all locks with a larger
-  ** BtShared address.  Then acquire our lock.  Then reacquire
-  ** the other BtShared locks that we used to hold in ascending
-  ** order.
-  */
-  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
-    assert( pLater->sharable );
-    assert( pLater->pNext==0 || pLater->pNext->pBt>pLater->pBt );
-    assert( !pLater->locked || pLater->wantToLock>0 );
-    if( pLater->locked ){
-      unlockBtreeMutex(pLater);
-    }
-  }
-  lockBtreeMutex(p);
-  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
-    if( pLater->wantToLock ){
-      lockBtreeMutex(pLater);
-    }
-  }
-}
-
-
-/*
-** Exit the recursive mutex on a Btree.
-*/
-void sqlite3BtreeLeave(Btree *p){
-  if( p->sharable ){
-    assert( p->wantToLock>0 );
-    p->wantToLock--;
-    if( p->wantToLock==0 ){
-      unlockBtreeMutex(p);
-    }
-  }
-}
-
-#ifndef NDEBUG
-/*
-** Return true if the BtShared mutex is held on the btree, or if the
-** B-Tree is not marked as sharable.
-**
-** This routine is used only from within assert() statements.
-*/
-int sqlite3BtreeHoldsMutex(Btree *p){
-  assert( p->sharable==0 || p->locked==0 || p->wantToLock>0 );
-  assert( p->sharable==0 || p->locked==0 || p->db==p->pBt->db );
-  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->pBt->mutex) );
-  assert( p->sharable==0 || p->locked==0 || sqlite3_mutex_held(p->db->mutex) );
-
-  return (p->sharable==0 || p->locked);
-}
-#endif
-
-
-#ifndef SQLITE_OMIT_INCRBLOB
-/*
-** Enter and leave a mutex on a Btree given a cursor owned by that
-** Btree.  These entry points are used by incremental I/O and can be
-** omitted if that module is not used.
-*/
-void sqlite3BtreeEnterCursor(BtCursor *pCur){
-  sqlite3BtreeEnter(pCur->pBtree);
-}
-void sqlite3BtreeLeaveCursor(BtCursor *pCur){
-  sqlite3BtreeLeave(pCur->pBtree);
-}
-#endif /* SQLITE_OMIT_INCRBLOB */
-
-
-/*
-** Enter the mutex on every Btree associated with a database
-** connection.  This is needed (for example) prior to parsing
-** a statement since we will be comparing table and column names
-** against all schemas and we do not want those schemas being
-** reset out from under us.
-**
-** There is a corresponding leave-all procedures.
-**
-** Enter the mutexes in accending order by BtShared pointer address
-** to avoid the possibility of deadlock when two threads with
-** two or more btrees in common both try to lock all their btrees
-** at the same instant.
-*/
-void sqlite3BtreeEnterAll(sqlite3 *db){
-  int i;
-  Btree *p;
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(i=0; i<db->nDb; i++){
-    p = db->aDb[i].pBt;
-    if( p ) sqlite3BtreeEnter(p);
-  }
-}
-void sqlite3BtreeLeaveAll(sqlite3 *db){
-  int i;
-  Btree *p;
-  assert( sqlite3_mutex_held(db->mutex) );
-  for(i=0; i<db->nDb; i++){
-    p = db->aDb[i].pBt;
-    if( p ) sqlite3BtreeLeave(p);
-  }
-}
-
-/*
-** Return true if a particular Btree requires a lock.  Return FALSE if
-** no lock is ever required since it is not sharable.
-*/
-int sqlite3BtreeSharable(Btree *p){
-  return p->sharable;
-}
-
-#ifndef NDEBUG
-/*
-** Return true if the current thread holds the database connection
-** mutex and all required BtShared mutexes.
-**
-** This routine is used inside assert() statements only.
-*/
-int sqlite3BtreeHoldsAllMutexes(sqlite3 *db){
-  int i;
-  if( !sqlite3_mutex_held(db->mutex) ){
-    return 0;
-  }
-  for(i=0; i<db->nDb; i++){
-    Btree *p;
-    p = db->aDb[i].pBt;
-    if( p && p->sharable &&
-         (p->wantToLock==0 || !sqlite3_mutex_held(p->pBt->mutex)) ){
-      return 0;
-    }
-  }
-  return 1;
-}
-#endif /* NDEBUG */
-
-#ifndef NDEBUG
-/*
-** Return true if the correct mutexes are held for accessing the
-** db->aDb[iDb].pSchema structure.  The mutexes required for schema
-** access are:
-**
-**   (1) The mutex on db
-**   (2) if iDb!=1, then the mutex on db->aDb[iDb].pBt.
-**
-** If pSchema is not NULL, then iDb is computed from pSchema and
-** db using sqlite3SchemaToIndex().
-*/
-int sqlite3SchemaMutexHeld(sqlite3 *db, int iDb, Schema *pSchema){
-  Btree *p;
-  assert( db!=0 );
-  if( pSchema ) iDb = sqlite3SchemaToIndex(db, pSchema);
-  assert( iDb>=0 && iDb<db->nDb );
-  if( !sqlite3_mutex_held(db->mutex) ) return 0;
-  if( iDb==1 ) return 1;
-  p = db->aDb[iDb].pBt;
-  assert( p!=0 );
-  return p->sharable==0 || p->locked==1;
-}
-#endif /* NDEBUG */
-
-#else /* SQLITE_THREADSAFE>0 above.  SQLITE_THREADSAFE==0 below */
-/*
-** The following are special cases for mutex enter routines for use
-** in single threaded applications that use shared cache.  Except for
-** these two routines, all mutex operations are no-ops in that case and
-** are null #defines in btree.h.
-**
-** If shared cache is disabled, then all btree mutex routines, including
-** the ones below, are no-ops and are null #defines in btree.h.
-*/
-
-void sqlite3BtreeEnter(Btree *p){
-  p->pBt->db = p->db;
-}
-void sqlite3BtreeEnterAll(sqlite3 *db){
-  int i;
-  for(i=0; i<db->nDb; i++){
-    Btree *p = db->aDb[i].pBt;
-    if( p ){
-      p->pBt->db = p->db;
-    }
-  }
-}
-#endif /* if SQLITE_THREADSAFE */
-#endif /* ifndef SQLITE_OMIT_SHARED_CACHE */