SQLite

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.103 2002/11/01 01:55:37 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** A pointer to this structure is used to communicate information

    while( (rc = sqliteInit(db, pzErrMsg))==SQLITE_BUSY
       && db->xBusyCallback && db->xBusyCallback(db->pBusyArg, "", cnt++)!=0 ){}
    if( rc!=SQLITE_OK ){
      sqliteStrRealloc(pzErrMsg);
      sqliteSafetyOff(db);
      return rc;
    }
    if( pzErrMsg ){
      sqliteFree(*pzErrMsg);
      *pzErrMsg = 0;
    }
  }
  if( db->file_format<3 ){
    sqliteSafetyOff(db);
    sqliteSetString(pzErrMsg, "obsolete database file format", 0);
    return SQLITE_ERROR;
  }
  if( db->recursionDepth==0 ){ db->nChange = 0; }

** few places in the code that are even potentially unsafe, and those
** places execute for very short periods of time.  So even if the library
** is compiled with its mutexes disabled, it is likely to work correctly
** in a multi-threaded program most of the time.  
*/
#include "sqlite.h"
#include <pthread.h>
#include <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

/*
** Enable for tracing
*/
static int verbose = 0;

/*
** Come here to die.
*/
static void Exit(int rc){
  exit(rc);
}

extern char *sqlite_mprintf(const char *zFormat, ...);
extern char *sqlite_vmprintf(const char *zFormat, va_list);

/*
** When a lock occurs, yield.
*/
static int db_is_locked(void *NotUsed, const char *zNotUsed, int iNotUsed){
  /* sched_yield(); */
  if( verbose ) printf("BUSY %s\n", (char*)NotUsed);
  usleep(100);
  return 1;
}

/*
** Used to accumulate query results by db_query()
*/
struct QueryResult {
  const char *zFile;  /* Filename - used for error reporting */
  int nElem;          /* Number of used entries in azElem[] */

    if( pResult->nAlloc==0 ){
      pResult->nAlloc = nArg+1;
    }else{
      pResult->nAlloc = pResult->nAlloc*2 + nArg + 1;
    }
    pResult->azElem = realloc( pResult->azElem, pResult->nAlloc*sizeof(char*));
    if( pResult->azElem==0 ){
      fprintf(stdout,"%s: malloc failed\n", pResult->zFile);
      return 1;
    }
  }
  if( azArg==0 ) return 0;
  for(i=0; i<nArg; i++){
    pResult->azElem[pResult->nElem++] =
        sqlite_mprintf("%s",azArg[i] ? azArg[i] : ""); 

  va_list ap;
  struct QueryResult sResult;
  va_start(ap, zFormat);
  zSql = sqlite_vmprintf(zFormat, ap);
  va_end(ap);
  memset(&sResult, 0, sizeof(sResult));
  sResult.zFile = zFile;
  if( verbose ) printf("QUERY %s: %s\n", zFile, zSql);
  rc = sqlite_exec(db, zSql, db_query_callback, &sResult, &zErrMsg);
  if( rc==SQLITE_SCHEMA ){
    if( zErrMsg ) free(zErrMsg);
    rc = sqlite_exec(db, zSql, db_query_callback, &sResult, &zErrMsg);
  }
  if( verbose ) printf("DONE %s %s\n", zFile, zSql);
  if( zErrMsg ){
    fprintf(stdout,"%s: query failed: %s - %s\n", zFile, zSql, zErrMsg);
    free(zErrMsg);
    free(zSql);
    Exit(1);
  }
  sqlite_freemem(zSql);
  if( sResult.azElem==0 ){
    db_query_callback(&sResult, 0, 0, 0);

  char *zSql;
  int rc;
  char *zErrMsg = 0;
  va_list ap;
  va_start(ap, zFormat);
  zSql = sqlite_vmprintf(zFormat, ap);
  va_end(ap);
  if( verbose ) printf("EXEC %s: %s\n", zFile, zSql);
  rc = sqlite_exec(db, zSql, 0, 0, &zErrMsg);
  if( rc==SQLITE_SCHEMA ){
    if( zErrMsg ) free(zErrMsg);
    rc = sqlite_exec(db, zSql, 0, 0, &zErrMsg);
  }
  if( verbose ) printf("DONE %s: %s\n", zFile, zSql);
  if( zErrMsg ){
    fprintf(stdout,"%s: command failed: %s - %s\n", zFile, zSql, zErrMsg);
    free(zErrMsg);
    sqlite_freemem(zSql);
    Exit(1);
  }
  sqlite_freemem(zSql);
}

void db_check(const char *zFile, const char *zMsg, char **az, ...){
  va_list ap;
  int i;
  char *z;
  va_start(ap, az);
  for(i=0; (z = va_arg(ap, char*))!=0; i++){
    if( az[i]==0 || strcmp(az[i],z)!=0 ){
      fprintf(stdout,"%s: %s: bad result in column %d: %s\n",
        zFile, zMsg, i+1, az[i]);
      db_query_free(az);
      Exit(1);
    }
  }
  va_end(ap);
  db_query_free(az);
}

pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t sig = PTHREAD_COND_INITIALIZER;
int thread_cnt = 0;

static void *worker_bee(void *pArg){
  const char *zFilename = (char*)pArg;
  char *azErr;
  int i, cnt;
  int t = atoi(zFilename);
  char **az;
  sqlite *db;

  pthread_mutex_lock(&lock);
  thread_cnt++;
  pthread_mutex_unlock(&lock);
  printf("%s: START\n", zFilename);
  fflush(stdout);
  for(cnt=0; cnt<10; cnt++){
    db = sqlite_open(&zFilename[2], 0, &azErr);
    if( db==0 ){
      fprintf(stdout,"%s: can't open\n", zFilename);
      Exit(1);
    }
    sqlite_busy_handler(db, db_is_locked, zFilename);
    db_execute(db, zFilename, "CREATE TABLE t%d(a,b,c);", t);
    for(i=1; i<=100; i++){
      db_execute(db, zFilename, "INSERT INTO t%d VALUES(%d,%d,%d);",
         t, i, i*2, i*i);
    }
    az = db_query(db, zFilename, "SELECT count(*) FROM t%d", t);
    db_check(zFilename, "tX size", az, "100", 0);  
    az = db_query(db, zFilename, "SELECT avg(b) FROM t%d", t);
    db_check(zFilename, "tX avg", az, "101", 0);  
    db_execute(db, zFilename, "DELETE FROM t%d WHERE a>50", t);
    az = db_query(db, zFilename, "SELECT avg(b) FROM t%d", t);
    db_check(zFilename, "tX avg2", az, "51", 0);
    for(i=1; i<=50; i++){
      char z1[30], z2[30];
      az = db_query(db, zFilename, "SELECT b, c FROM t%d WHERE a=%d", t, i);
      sprintf(z1, "%d", i*2);
      sprintf(z2, "%d", i*i);
      db_check(zFilename, "readback", az, z1, z2, 0);
    }
    db_execute(db, zFilename, "DROP TABLE t%d;", t);
    sqlite_close(db);
  }
  printf("%s: END\n", zFilename);
  /* unlink(zFilename); */
  fflush(stdout);
  pthread_mutex_lock(&lock);
  thread_cnt--;
  if( thread_cnt<=0 ){
    pthread_cond_signal(&sig);
  }
  pthread_mutex_unlock(&lock);
  return 0;
}

int main(int argc, char **argv){
  char *zFile;
  int i, n;
  pthread_t id;
  if( argc>2 && strcmp(argv[1], "-v")==0 ){
    verbose = 1;
    argc--;
    argv++;
  }
  if( argc<2 || (n=atoi(argv[1]))<1 ) n = 10;
  for(i=0; i<n; i++){
    char zBuf[200];
    sprintf(zBuf, "testdb-%d", (i+1)/2);
    unlink(zBuf);
  }
  for(i=0; i<n; i++){
    zFile = sqlite_mprintf("%d.testdb-%d", i%2+1, (i+2)/2);
    unlink(zFile);
    pthread_create(&id, 0, worker_bee, (void*)zFile);
    pthread_detach(id);
  }
  pthread_mutex_lock(&lock);
  while( thread_cnt>0 ){
    pthread_cond_wait(&sig, &lock);
  }
  pthread_mutex_unlock(&lock);
  for(i=0; i<n; i++){
    char zBuf[200];
    sprintf(zBuf, "testdb-%d", (i+1)/2);
    unlink(zBuf);
  }
  return 0;
}

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.183 2002/11/01 01:55:38 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The makefile scans this source file and creates the following
** array of string constants which are the names of all VDBE opcodes.

  int i = pOp->p1;
  VERIFY( if( NeedStack(p, tos) ) goto no_mem; )
  VERIFY( if( i<0 || i>=p->nMem ) goto bad_instruction; )
  memcpy(&aStack[tos], &p->aMem[i].s, sizeof(aStack[tos])-NBFS);;
  if( aStack[tos].flags & STK_Str ){
    zStack[tos] = p->aMem[i].z;
    aStack[tos].flags |= STK_Ephem;
    aStack[tos].flags &= ~(STK_Dyn|STK_Static);
  }
  break;
}

/* Opcode: MemIncr P1 P2 *
**
** Increment the integer valued memory cell P1 by 1.  If P2 is not zero

          zBuf[k++] = ']';
          zBuf[k++] = 0;
          fprintf(p->trace, "%s", zBuf);
        }else{
          fprintf(p->trace, " ???");
        }
      }
      if( rc!=0 ) fprintf(p->trace," rc=%d",rc);
      fprintf(p->trace,"\n");
    }
#endif
  }

cleanup:
  Cleanup(p);