| Index: third_party/sqlite/src/mutex_os2.c
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| ===================================================================
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| --- third_party/sqlite/src/mutex_os2.c	(revision 56608)
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| +++ third_party/sqlite/src/mutex_os2.c	(working copy)
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| @@ -1,273 +0,0 @@
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| -/*
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| -** 2007 August 28
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| -**
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| -** The author disclaims copyright to this source code.  In place of
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| -** a legal notice, here is a blessing:
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| -**
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| -**    May you do good and not evil.
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| -**    May you find forgiveness for yourself and forgive others.
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| -**    May you share freely, never taking more than you give.
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| -**
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| -*************************************************************************
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| -** This file contains the C functions that implement mutexes for OS/2
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| -**
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| -** $Id: mutex_os2.c,v 1.11 2008/11/22 19:50:54 pweilbacher Exp $
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| -*/
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| -#include "sqliteInt.h"
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| -
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| -/*
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| -** The code in this file is only used if SQLITE_MUTEX_OS2 is defined.
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| -** See the mutex.h file for details.
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| -*/
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| -#ifdef SQLITE_MUTEX_OS2
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| -
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| -/********************** OS/2 Mutex Implementation **********************
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| -**
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| -** This implementation of mutexes is built using the OS/2 API.
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| -*/
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| -
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| -/*
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| -** The mutex object
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| -** Each recursive mutex is an instance of the following structure.
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| -*/
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| -struct sqlite3_mutex {
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| -  HMTX mutex;       /* Mutex controlling the lock */
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| -  int  id;          /* Mutex type */
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| -  int  nRef;        /* Number of references */
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| -  TID  owner;       /* Thread holding this mutex */
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| -};
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| -
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| -#define OS2_MUTEX_INITIALIZER   0,0,0,0
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| -
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| -/*
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| -** Initialize and deinitialize the mutex subsystem.
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| -*/
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| -static int os2MutexInit(void){ return SQLITE_OK; }
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| -static int os2MutexEnd(void){ return SQLITE_OK; }
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| -
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| -/*
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| -** The sqlite3_mutex_alloc() routine allocates a new
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| -** mutex and returns a pointer to it.  If it returns NULL
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| -** that means that a mutex could not be allocated. 
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| -** SQLite will unwind its stack and return an error.  The argument
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| -** to sqlite3_mutex_alloc() is one of these integer constants:
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| -**
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| -** <ul>
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| -** <li>  SQLITE_MUTEX_FAST               0
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| -** <li>  SQLITE_MUTEX_RECURSIVE          1
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| -** <li>  SQLITE_MUTEX_STATIC_MASTER      2
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| -** <li>  SQLITE_MUTEX_STATIC_MEM         3
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| -** <li>  SQLITE_MUTEX_STATIC_PRNG        4
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| -** </ul>
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| -**
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| -** The first two constants cause sqlite3_mutex_alloc() to create
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| -** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
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| -** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
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| -** The mutex implementation does not need to make a distinction
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| -** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
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| -** not want to.  But SQLite will only request a recursive mutex in
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| -** cases where it really needs one.  If a faster non-recursive mutex
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| -** implementation is available on the host platform, the mutex subsystem
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| -** might return such a mutex in response to SQLITE_MUTEX_FAST.
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| -**
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| -** The other allowed parameters to sqlite3_mutex_alloc() each return
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| -** a pointer to a static preexisting mutex.  Three static mutexes are
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| -** used by the current version of SQLite.  Future versions of SQLite
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| -** may add additional static mutexes.  Static mutexes are for internal
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| -** use by SQLite only.  Applications that use SQLite mutexes should
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| -** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
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| -** SQLITE_MUTEX_RECURSIVE.
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| -**
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| -** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
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| -** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
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| -** returns a different mutex on every call.  But for the static
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| -** mutex types, the same mutex is returned on every call that has
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| -** the same type number.
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| -*/
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| -static sqlite3_mutex *os2MutexAlloc(int iType){
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| -  sqlite3_mutex *p = NULL;
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| -  switch( iType ){
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| -    case SQLITE_MUTEX_FAST:
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| -    case SQLITE_MUTEX_RECURSIVE: {
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| -      p = sqlite3MallocZero( sizeof(*p) );
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| -      if( p ){
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| -        p->id = iType;
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| -        if( DosCreateMutexSem( 0, &p->mutex, 0, FALSE ) != NO_ERROR ){
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| -          sqlite3_free( p );
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| -          p = NULL;
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| -        }
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| -      }
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| -      break;
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| -    }
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| -    default: {
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| -      static volatile int isInit = 0;
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| -      static sqlite3_mutex staticMutexes[] = {
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| -        { OS2_MUTEX_INITIALIZER, },
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| -        { OS2_MUTEX_INITIALIZER, },
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| -        { OS2_MUTEX_INITIALIZER, },
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| -        { OS2_MUTEX_INITIALIZER, },
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| -        { OS2_MUTEX_INITIALIZER, },
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| -        { OS2_MUTEX_INITIALIZER, },
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| -      };
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| -      if ( !isInit ){
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| -        APIRET rc;
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| -        PTIB ptib;
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| -        PPIB ppib;
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| -        HMTX mutex;
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| -        char name[32];
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| -        DosGetInfoBlocks( &ptib, &ppib );
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| -        sqlite3_snprintf( sizeof(name), name, "\\SEM32\\SQLITE%04x",
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| -                          ppib->pib_ulpid );
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| -        while( !isInit ){
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| -          mutex = 0;
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| -          rc = DosCreateMutexSem( name, &mutex, 0, FALSE);
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| -          if( rc == NO_ERROR ){
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| -            unsigned int i;
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| -            if( !isInit ){
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| -              for( i = 0; i < sizeof(staticMutexes)/sizeof(staticMutexes[0]); i++ ){
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| -                DosCreateMutexSem( 0, &staticMutexes[i].mutex, 0, FALSE );
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| -              }
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| -              isInit = 1;
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| -            }
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| -            DosCloseMutexSem( mutex );
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| -          }else if( rc == ERROR_DUPLICATE_NAME ){
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| -            DosSleep( 1 );
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| -          }else{
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| -            return p;
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| -          }
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| -        }
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| -      }
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| -      assert( iType-2 >= 0 );
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| -      assert( iType-2 < sizeof(staticMutexes)/sizeof(staticMutexes[0]) );
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| -      p = &staticMutexes[iType-2];
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| -      p->id = iType;
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| -      break;
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| -    }
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| -  }
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| -  return p;
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| -}
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| -
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| -
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| -/*
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| -** This routine deallocates a previously allocated mutex.
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| -** SQLite is careful to deallocate every mutex that it allocates.
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| -*/
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| -static void os2MutexFree(sqlite3_mutex *p){
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| -  if( p==0 ) return;
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| -  assert( p->nRef==0 );
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| -  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
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| -  DosCloseMutexSem( p->mutex );
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| -  sqlite3_free( p );
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| -}
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| -
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| -/*
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| -** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
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| -** to enter a mutex.  If another thread is already within the mutex,
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| -** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
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| -** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
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| -** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
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| -** be entered multiple times by the same thread.  In such cases the,
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| -** mutex must be exited an equal number of times before another thread
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| -** can enter.  If the same thread tries to enter any other kind of mutex
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| -** more than once, the behavior is undefined.
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| -*/
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| -static void os2MutexEnter(sqlite3_mutex *p){
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| -  TID tid;
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| -  PID holder1;
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| -  ULONG holder2;
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| -  if( p==0 ) return;
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| -  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
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| -  DosRequestMutexSem(p->mutex, SEM_INDEFINITE_WAIT);
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| -  DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
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| -  p->owner = tid;
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| -  p->nRef++;
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| -}
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| -static int os2MutexTry(sqlite3_mutex *p){
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| -  int rc;
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| -  TID tid;
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| -  PID holder1;
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| -  ULONG holder2;
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| -  if( p==0 ) return SQLITE_OK;
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| -  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
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| -  if( DosRequestMutexSem(p->mutex, SEM_IMMEDIATE_RETURN) == NO_ERROR) {
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| -    DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
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| -    p->owner = tid;
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| -    p->nRef++;
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| -    rc = SQLITE_OK;
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| -  } else {
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| -    rc = SQLITE_BUSY;
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| -  }
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| -
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| -  return rc;
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| -}
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| -
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| -/*
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| -** The sqlite3_mutex_leave() routine exits a mutex that was
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| -** previously entered by the same thread.  The behavior
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| -** is undefined if the mutex is not currently entered or
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| -** is not currently allocated.  SQLite will never do either.
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| -*/
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| -static void os2MutexLeave(sqlite3_mutex *p){
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| -  TID tid;
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| -  PID holder1;
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| -  ULONG holder2;
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| -  if( p==0 ) return;
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| -  assert( p->nRef>0 );
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| -  DosQueryMutexSem(p->mutex, &holder1, &tid, &holder2);
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| -  assert( p->owner==tid );
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| -  p->nRef--;
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| -  assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
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| -  DosReleaseMutexSem(p->mutex);
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| -}
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| -
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| -#ifdef SQLITE_DEBUG
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| -/*
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| -** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
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| -** intended for use inside assert() statements.
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| -*/
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| -static int os2MutexHeld(sqlite3_mutex *p){
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| -  TID tid;
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| -  PID pid;
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| -  ULONG ulCount;
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| -  PTIB ptib;
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| -  if( p!=0 ) {
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| -    DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
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| -  } else {
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| -    DosGetInfoBlocks(&ptib, NULL);
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| -    tid = ptib->tib_ptib2->tib2_ultid;
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| -  }
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| -  return p==0 || (p->nRef!=0 && p->owner==tid);
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| -}
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| -static int os2MutexNotheld(sqlite3_mutex *p){
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| -  TID tid;
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| -  PID pid;
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| -  ULONG ulCount;
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| -  PTIB ptib;
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| -  if( p!= 0 ) {
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| -    DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
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| -  } else {
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| -    DosGetInfoBlocks(&ptib, NULL);
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| -    tid = ptib->tib_ptib2->tib2_ultid;
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| -  }
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| -  return p==0 || p->nRef==0 || p->owner!=tid;
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| -}
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| -#endif
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| -
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| -sqlite3_mutex_methods *sqlite3DefaultMutex(void){
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| -  static sqlite3_mutex_methods sMutex = {
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| -    os2MutexInit,
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| -    os2MutexEnd,
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| -    os2MutexAlloc,
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| -    os2MutexFree,
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| -    os2MutexEnter,
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| -    os2MutexTry,
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| -    os2MutexLeave,
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| -#ifdef SQLITE_DEBUG
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| -    os2MutexHeld,
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| -    os2MutexNotheld
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| -#endif
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| -  };
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| -
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| -  return &sMutex;
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| -}
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| -#endif /* SQLITE_MUTEX_OS2 */
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| 
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