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Overview
Comment:Fix a race condtion in test_async.c. (CVS 4516)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 5e3f7c3dec3e8d92b28a74293387b390fe6fc1fa
User & Date: danielk1977 2007-10-30 15:29:43
Context
2007-10-30
15:38
Remove a debugging assert() that went in by accident with the previous commit. (CVS 4517) check-in: 4ad60bdb user: danielk1977 tags: trunk
15:29
Fix a race condtion in test_async.c. (CVS 4516) check-in: 5e3f7c3d user: danielk1977 tags: trunk
2007-10-27
16:25
Clarify the behavior of sqlite3_last_insert_rowid() when using INSERT OR IGNORE. (CVS 4515) check-in: c0fa0c8b user: drh tags: trunk
Changes
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Changes to src/test_async.c.

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** and processing them in the order in which they arrive.
**
** An artifical delay of async.ioDelay milliseconds is inserted before
** each write operation in order to simulate the effect of a slow disk.
**
** Only one instance of this procedure may be running at a time.
*/
static void *asyncWriterThread(void *NotUsed){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)(async_vfs.pAppData);
  AsyncWrite *p = 0;
  int rc = SQLITE_OK;
  int holdingMutex = 0;

  if( pthread_mutex_trylock(&async.writerMutex) ){
    return 0;
  }

  while( async.writerHaltNow==0 ){
    int doNotFree = 0;
    sqlite3_file *pBase = 0;

    if( !holdingMutex ){
      pthread_mutex_lock(&async.queueMutex);
    }
................................................................................
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  pthread_t x;
  int rc;

  rc = pthread_create(&x, 0, asyncWriterThread, 0);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    return TCL_ERROR;
  }
  pthread_detach(x);



  return TCL_OK;
}

/*
** sqlite3async_wait
**
** Wait for the current writer thread to terminate.
................................................................................
static int testAsyncWait(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int cnt = 10;

  if( async.writerHaltNow==0 && async.writerHaltWhenIdle==0 ){
    Tcl_AppendResult(interp, "would block forever", (char*)0);
    return TCL_ERROR;
  }

  while( cnt-- && !pthread_mutex_trylock(&async.writerMutex) ){
    pthread_mutex_unlock(&async.writerMutex);







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** and processing them in the order in which they arrive.
**
** An artifical delay of async.ioDelay milliseconds is inserted before
** each write operation in order to simulate the effect of a slow disk.
**
** Only one instance of this procedure may be running at a time.
*/
static void *asyncWriterThread(void *pIsStarted){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)(async_vfs.pAppData);
  AsyncWrite *p = 0;
  int rc = SQLITE_OK;
  int holdingMutex = 0;

  if( pthread_mutex_trylock(&async.writerMutex) ){
    return 0;
  }
  (*(int *)pIsStarted) = 1;
  while( async.writerHaltNow==0 ){
    int doNotFree = 0;
    sqlite3_file *pBase = 0;

    if( !holdingMutex ){
      pthread_mutex_lock(&async.queueMutex);
    }
................................................................................
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  pthread_t x;
  int rc;
  volatile int isStarted = 0;
  rc = pthread_create(&x, 0, asyncWriterThread, &isStarted);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    return TCL_ERROR;
  }
  pthread_detach(x);
  while( isStarted==0 ){
    sched_yield();
  }
  return TCL_OK;
}

/*
** sqlite3async_wait
**
** Wait for the current writer thread to terminate.
................................................................................
static int testAsyncWait(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int cnt = 10;
  assert(async.writerHaltNow==0);
  if( async.writerHaltNow==0 && async.writerHaltWhenIdle==0 ){
    Tcl_AppendResult(interp, "would block forever", (char*)0);
    return TCL_ERROR;
  }

  while( cnt-- && !pthread_mutex_trylock(&async.writerMutex) ){
    pthread_mutex_unlock(&async.writerMutex);