/*

** 2004 January 13

**

** 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 implements a simple standalone program used to test whether

** or not the SQLite library is threadsafe.

**

** This file is NOT part of the standard SQLite library.  It is used for

** testing only.

*/

#include <stdio.h>

#include <unistd.h>

#include <pthread.h>

#include <string.h>

#include <stdlib.h>

#include "sqlite.h"

/*

** Name of the database

*/

#define DB_FILE "test.db"

/* 

** When this variable becomes non-zero, all threads stop

** what they are doing.

*/

volatile int all_stop = 0;

/* 

** Callback from the integrity check.  If the result is anything other

** than "ok" it means the integrity check has failed.  Set the "all_stop"

** global variable to stop all other activity.  Print the error message

** or print OK if the string "ok" is seen.

*/

int check_callback(void *pid, int argc, char **argv, char **notUsed2){

  int id = (int)pid;

  if( strcmp(argv[0],"ok") ){

    all_stop = 1;

    fprintf(stderr,"id: %s\n", id, argv[0]);

  }else{

    /* fprintf(stderr,"%d: OK\n", id); */

  }

  return 0;

}

/*

** Do an integrity check on the database.  If the first integrity check

** fails, try it a second time.

*/

int integrity_check(sqlite *db, int id){

  int rc;

  if( all_stop ) return 0;

  /* fprintf(stderr,"%d: CHECK\n", id); */

  rc = sqlite3_exec(db, "pragma integrity_check", check_callback, 0, 0);

  if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){

    fprintf(stderr,"%d, Integrity check returns %d\n", id, rc);

  }

  if( all_stop ){

    sqlite3_exec(db, "pragma integrity_check", check_callback, 0, 0);

  }

  return 0;

}

/*

** This is the worker thread

*/

void *worker(void *workerArg){

  sqlite *db;

  int id = (int)workerArg;

  int rc;

  int cnt = 0;

  fprintf(stderr, "Starting worker %d\n", id);

  while( !all_stop && cnt++<10000 ){

    if( cnt%100==0 ) printf("%d: %d\n", id, cnt);

    while( (sqlite3_open(DB_FILE, &db))!=SQLITE_OK ) sched_yield();

    sqlite3_exec(db, "PRAGMA synchronous=OFF", 0, 0, 0);

    /* integrity_check(db, id); */

    if( all_stop ){ sqlite3_close(db); break; }

    /* fprintf(stderr, "%d: BEGIN\n", id); */

    rc = sqlite3_exec(db, "INSERT INTO t1 VALUES('bogus data')", 0, 0, 0);

    /* fprintf(stderr, "%d: END rc=%d\n", id, rc); */

    sqlite3_close(db);

  }

  fprintf(stderr, "Worker %d finished\n", id);

  return 0;

}

/*

** Initialize the database and start the threads

*/

int main(int argc, char **argv){

  sqlite *db;

  int i, rc;

  pthread_t aThread[5];

  if( strcmp(DB_FILE,":memory:") ){

    char *zJournal = sqlite3_mprintf("%s-journal", DB_FILE);

    unlink(DB_FILE);

    unlink(zJournal);

    sqlite3_free(zJournal);

  }  

  sqlite3_open(DB_FILE, &db);

  if( db==0 ){

    fprintf(stderr,"unable to initialize database\n");

    exit(1);

  }

  rc = sqlite3_exec(db, "CREATE TABLE t1(x);", 0,0,0);

  if( rc ){

    fprintf(stderr,"cannot create table t1: %d\n", rc);

    exit(1);

  }

  sqlite3_close(db);

  for(i=0; i<sizeof(aThread)/sizeof(aThread[0]); i++){

    pthread_create(&aThread[i], 0, worker, (void*)i);

  }

  for(i=0; i<sizeof(aThread)/sizeof(aThread[i]); i++){

    pthread_join(aThread[i], 0);

  }

  if( !all_stop ){

    printf("Everything seems ok.\n");

    return 0;

  }else{

    printf("We hit an error.\n");

    return 1;

  }

}