SQLite

int sqlite3OsSyncDirectory(const char*);
int sqlite3OsTempFileName(char*);
int sqlite3OsRandomSeed(char*);
int sqlite3OsSleep(int ms);
int sqlite3OsCurrentTime(double*);
void sqlite3OsEnterMutex(void);
void sqlite3OsLeaveMutex(void);
int sqlite3OsInMutex(int);
ThreadData *sqlite3OsThreadSpecificData(int);
void *sqlite3OsMalloc(int);
void *sqlite3OsRealloc(void *, int);
void sqlite3OsFree(void *);
int sqlite3OsAllocationSize(void *);

/*

}
#endif /* SQLITE_UNIX_THREADS */

/*
** Release a lockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct lockInfo *pLock){
  assert( sqlite3OsInMutex(1) );
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqliteFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
  assert( sqlite3OsInMutex(1) );
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    free(pOpen->aPending);
    sqliteFree(pOpen);
  }
}

  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ) return 1;

  assert( sqlite3OsInMutex(1) );
  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
  key1.ino = statbuf.st_ino;
#ifdef SQLITE_UNIX_THREADS
  if( threadsOverrideEachOthersLocks<0 ){
    testThreadLockingBehavior(fd);
  }

** The following pair of routine implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
**
** As of version 3.3.2, this mutex must be recursive.
*/
void sqlite3UnixEnterMutex(){
#ifdef SQLITE_UNIX_THREADS
  pthread_mutex_lock(&mutex1);
  if( inMutex==0 ){
    pthread_mutex_lock(&mutex2);
    mutexOwner = pthread_self();

  pthread_mutex_unlock(&mutex1);
#else
  inMutex--;
#endif
}

/*
** Return TRUE if the mutex is currently held.
**
** If the thisThreadOnly parameter is true, return true only if the
** calling thread holds the mutex.  If the parameter is false, return
** true if any thread holds the mutex.
*/
int sqlite3UnixInMutex(int thisThreadOnly){
#ifdef SQLITE_UNIX_THREADS
  return inMutex>0 && 
           (thisThreadOnly==0 || pthread_equal(mutexOwner, pthread_self()));
#else
  return inMutex>0;
#endif
}

/*
** Remember the number of thread-specific-data blocks allocated.
** Use this to verify that we are not leaking thread-specific-data.
** Ticket #1601

}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_W32_THREADS
  static DWORD mutexOwner;
  static CRITICAL_SECTION cs;
#endif

/*
** The following pair of routines implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
**
** Version 3.3.1 and earlier used a simple mutex.  Beginning with
** version 3.3.2, a recursive mutex is required.
*/
void sqlite3WinEnterMutex(){
#ifdef SQLITE_W32_THREADS
  static int isInit = 0;
  while( !isInit ){
    static long lock = 0;
    if( InterlockedIncrement(&lock)==1 ){
      InitializeCriticalSection(&cs);
      isInit = 1;
    }else{
      Sleep(1);
    }
  }
  EnterCriticalSection(&cs);
  mutexOwner = GetCurrentThreadId();
#endif
  inMutex++;
}
void sqlite3WinLeaveMutex(){
  assert( inMutex );
  inMutex--;
#ifdef SQLITE_W32_THREADS
  assert( mutexOwner==GetCurrentThreadId() );
  LeaveCriticalSection(&cs);
#endif
}

/*
** Return TRUE if the mutex is currently held.
**
** If the thisThreadOnly parameter is true, return true if and only if the
** calling thread holds the mutex.  If the parameter is false, return
** true if any thread holds the mutex.
*/
int sqlite3WinInMutex(int thisThreadOnly){
#ifdef SQLITE_W32_THREADS
  return inMutex>0 && (thisThreadOnly==0 || mutexOwner==GetCurrentThreadId());
#else
  return inMutex>0;
#endif
}


/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.244 2006/01/18 17:25:46 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

  int i;

  /* If the the global mutex is held, this subroutine becomes a
  ** o-op; zero bytes of memory are freed.  This is because
  ** some of the code invoked by this function may also
  ** try to obtain the mutex, resulting in a deadlock.
  */
  if( sqlite3OsInMutex(0) ){
    return 0;
  }

  /* Outermost loop runs for at most two iterations. First iteration we
  ** try to find memory that can be released without calling fsync(). Second
  ** iteration (which only runs if the first failed to free nReq bytes of
  ** memory) is permitted to call fsync(). This is of course much more 

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.177 2006/01/18 17:25:46 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>

/*

}

/* 
** Return true is a malloc has failed in this thread since the last call
** to sqlite3ApiExit(), or false otherwise.
*/
int sqlite3MallocFailed(){
  return (mallocHasFailed && sqlite3OsInMutex(1));
}

/* 
** Set the "malloc has failed" condition to true for this thread.
*/
void sqlite3FailedMalloc(){
  sqlite3OsEnterMutex();