SQLite

/*
** 2008 Jan 22
**
** 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 contains code to implement a fault-injector used for
** testing and verification of SQLite.
**
** Subsystems within SQLite can call sqlite3FaultStep() to see if
** they should simulate a fault.  sqlite3FaultStep() normally returns
** zero but will return non-zero if a fault should be simulated.
** Fault injectors can be used, for example, to simulate memory

** allocation failures or I/O errors.
**
** The fault injector is omitted from the code if SQLite is
** compiled with -DSQLITE_OMIT_BUILTIN_TEST=1.  There is a very
** small performance hit for leaving the fault injector in the code.
** Commerical products will probably want to omit the fault injector
** from production builds.  But safety-critical systems who work
** under the motto "fly what you test and test what you fly" may
** choose to leave the fault injector enabled even in production.
**
** $Id: fault.c,v 1.7 2008/06/19 18:17:50 danielk1977 Exp $
*/

#include "sqliteInt.h"

/*
** There can be various kinds of faults.  For example, there can be
** a memory allocation failure.  Or an I/O failure.  For each different
** fault type, there is a separate FaultInjector structure to keep track
** of the status of that fault.
*/
static struct MemFault {
  int iCountdown;   /* Number of pending successes before we hit a failure */
  int nRepeat;      /* Number of times to repeat the failure */
  int nBenign;      /* Number of benign failures seen since last config */
  int nFail;        /* Number of failures seen since last config */
  u8 enable;        /* True if enabled */
  i16 benign;       /* Positive if next failure will be benign */

  int isInstalled;
  sqlite3_mem_methods m;         /* 'Real' malloc implementation */
} memfault;

/*
** This routine exists as a place to set a breakpoint that will
** fire on any simulated malloc() failure.
*/
static void sqlite3Fault(void){
  static int cnt = 0;
  cnt++;
}

/*
** Check to see if a fault should be simulated.  Return true to simulate
** the fault.  Return false if the fault should not be simulated.
*/
static int faultsimStep(){
  if( likely(!memfault.enable) ){
    return 0;
  }
  if( memfault.iCountdown>0 ){
    memfault.iCountdown--;
    return 0;
  }
  sqlite3Fault();
  memfault.nFail++;
  if( memfault.benign>0 ){
    memfault.nBenign++;
  }
  memfault.nRepeat--;
  if( memfault.nRepeat<=0 ){
    memfault.enable = 0;
  }
  return 1;  
}

static void *faultsimMalloc(int n){
  void *p = 0;
  if( !faultsimStep() ){
    p = memfault.m.xMalloc(n);
  }
  return p;
}


static void *faultsimRealloc(void *pOld, int n){
  void *p = 0;
  if( !faultsimStep() ){
    p = memfault.m.xRealloc(pOld, n);
  }
  return p;
}

/* 
** The following method calls are passed directly through to the underlying
** malloc system:
**
**     xFree
**     xSize
**     xRoundup
**     xInit
**     xShutdown
*/
static void faultsimFree(void *p){
  memfault.m.xFree(p);
}
static int faultsimSize(void *p){
  return memfault.m.xSize(p);
}
static int faultsimRoundup(int n){
  return memfault.m.xRoundup(n);
}
static int faultsimInit(void *p){
  return memfault.m.xInit(memfault.m.pAppData);
}
static void faultsimShutdown(void *p){
  memfault.m.xShutdown(memfault.m.pAppData);
}

/*
** This routine configures and enables a fault injector.  After
** calling this routine, a FaultStep() will return false (zero)
** nDelay times, then it will return true nRepeat times,
** then it will again begin returning false.
*/
void sqlite3FaultConfig(int id, int nDelay, int nRepeat){
  memfault.iCountdown = nDelay;
  memfault.nRepeat = nRepeat;
  memfault.nBenign = 0;
  memfault.nFail = 0;
  memfault.enable = nDelay>=0;
  memfault.benign = 0;
}

/*
** Return the number of faults (both hard and benign faults) that have
** occurred since the injector was last configured.
*/
int sqlite3FaultFailures(int id){
  assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
  return memfault.nFail;
}

/*
** Return the number of benign faults that have occurred since the
** injector was last configured.
*/
int sqlite3FaultBenignFailures(int id){
  return memfault.nBenign;
}

/*
** Return the number of successes that will occur before the next failure.
** If no failures are scheduled, return -1.
*/
int sqlite3FaultPending(int id){
  if( memfault.enable ){
    return memfault.iCountdown;
  }else{
    return -1;
  }
}

/* 
** After this routine causes subsequent faults to be either benign
** or hard (not benign), according to the "enable" parameter.
**
** Most faults are hard.  In other words, most faults cause
** an error to be propagated back up to the application interface.
** However, sometimes a fault is easily recoverable.  For example,
** if a malloc fails while resizing a hash table, this is completely
** recoverable simply by not carrying out the resize.  The hash table
** will continue to function normally.  So a malloc failure during
** a hash table resize is a benign fault.  
*/
void sqlite3FaultBeginBenign(int id){
  if( id<0 ){
    for(id=0; id<SQLITE_FAULTINJECTOR_COUNT; id++){
      memfault.benign++;
    }
  }else{
    assert( id>=0 && id<SQLITE_FAULTINJECTOR_COUNT );
    memfault.benign++;
  }
}
void sqlite3FaultEndBenign(int id){
  if( id<0 ){
    for(id=0; id<SQLITE_FAULTINJECTOR_COUNT; id++){
      assert( memfault.benign>0 );
      memfault.benign--;
    }
  }else{
    assert( memfault.benign>0 );
    memfault.benign--;
  }
}

int sqlite3FaultsimInstall(int install){
  static struct sqlite3_mem_methods m = {
    faultsimMalloc,                   /* xMalloc */
    faultsimFree,                     /* xFree */
    faultsimRealloc,                  /* xRealloc */
    faultsimSize,                     /* xSize */
    faultsimRoundup,                  /* xRoundup */
    faultsimInit,                     /* xInit */
    faultsimShutdown,                 /* xShutdown */
    0                                 /* pAppData */
  };
  int rc;

  assert(install==1 || install==0);
  assert(memfault.isInstalled==1 || memfault.isInstalled==0);

  if( install==memfault.isInstalled ){
    return SQLITE_ERROR;
  }

  rc = sqlite3_config(SQLITE_CONFIG_GETMALLOC, &memfault.m);
  assert(memfault.m.xMalloc);
  if( rc==SQLITE_OK ){
    rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &m);
  }

  if( rc==SQLITE_OK ){
    memfault.isInstalled = 1;
  }
  return rc;
}

**
*************************************************************************
** 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 1.453 2008/06/19 18:17:50 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif

*/
int sqlite3_test_control(int op, ...){
  int rc = 0;
#ifndef SQLITE_OMIT_BUILTIN_TEST
  va_list ap;
  va_start(ap, op);
  switch( op ){

    /*
    ** sqlite3_test_control(FAULT_CONFIG, fault_id, nDelay, nRepeat)
    **
    ** Configure a fault injector.  The specific fault injector is
    ** identified by the fault_id argument.  (ex: SQLITE_FAULTINJECTOR_MALLOC)
    ** The fault will occur after a delay of nDelay calls.  The fault
    ** will repeat nRepeat times.

    ** as a wrapper around the currently installed implementation.
    */
    case SQLITE_TESTCTRL_FAULT_INSTALL: {
      int isInstall = va_arg(ap, int);
      rc = sqlite3FaultsimInstall(isInstall);
      break;
    }


    /*
    ** Save the current state of the PRNG.
    */
    case SQLITE_TESTCTRL_PRNG_SAVE: {
      sqlite3PrngSaveState();
      break;

/*
** 2001 September 15
**
** 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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.718 2008/06/19 18:17:50 danielk1977 Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build

/*
** Available fault injectors.  Should be numbered beginning with 0.
*/
#define SQLITE_FAULTINJECTOR_MALLOC     0
#define SQLITE_FAULTINJECTOR_COUNT      1

/*
** The interface to the fault injector subsystem.  If the fault injector
** mechanism is disabled at compile-time then set up macros so that no
** unnecessary code is generated.
*/
#ifndef SQLITE_OMIT_BUILTIN_TEST
  void sqlite3FaultConfig(int,int,int);
  int sqlite3FaultFailures(int);
  int sqlite3FaultBenignFailures(int);
  int sqlite3FaultPending(int);
  void sqlite3FaultBeginBenign(int);
  void sqlite3FaultEndBenign(int);
  int sqlite3FaultStep(int);
  int sqlite3FaultsimInstall(int);
#else
# define sqlite3FaultConfig(A,B,C)
# define sqlite3FaultFailures(A)         0
# define sqlite3FaultBenignFailures(A)   0
# define sqlite3FaultPending(A)          (-1)
# define sqlite3FaultBeginBenign(A)
# define sqlite3FaultEndBenign(A)
# define sqlite3FaultStep(A)             0
#endif
  
  

#define IN_INDEX_ROWID           1
#define IN_INDEX_EPH             2
#define IN_INDEX_INDEX           3
int sqlite3FindInIndex(Parse *, Expr *, int);

#ifdef SQLITE_ENABLE_ATOMIC_WRITE

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.26 2008/06/19 18:17:50 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>



























































































































































































const char *sqlite3TestErrorName(int);

/*
** Transform pointers to text and back again
*/
static void pointerToText(void *p, char *z){
  static const char zHex[] = "0123456789abcdef";

    return TCL_ERROR;
  }
  p = sqlite3_realloc(pPrior, (unsigned)nByte);
  pointerToText(p, zOut);
  Tcl_AppendResult(interp, zOut, NULL);
  return TCL_OK;
}


/*
** Usage:    sqlite3_free  PRIOR
**
** Raw test interface for sqlite3_free().
*/
static int test_free(

    if( zErr ){
      Tcl_AppendResult(interp, zErr, zOption, 0);
      return TCL_ERROR;
    }
  }
  
  sqlite3_test_control(-12345); /* Just to stress the test_control interface */
  nBenign = sqlite3_test_control(SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES,
                                 SQLITE_FAULTINJECTOR_MALLOC);
  nFail = sqlite3_test_control(SQLITE_TESTCTRL_FAULT_FAILURES,
                               SQLITE_FAULTINJECTOR_MALLOC);
  sqlite3_test_control(SQLITE_TESTCTRL_FAULT_CONFIG,
                       SQLITE_FAULTINJECTOR_MALLOC, iFail, nRepeat);

  if( pBenignCnt ){
    Tcl_ObjSetVar2(interp, pBenignCnt, 0, Tcl_NewIntObj(nBenign), 0);
  }
  Tcl_SetObjResult(interp, Tcl_NewIntObj(nFail));
  return TCL_OK;
}

  Tcl_Obj *CONST objv[]
){
  int nPending;
  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }
  nPending = sqlite3_test_control(SQLITE_TESTCTRL_FAULT_PENDING,
                                  SQLITE_FAULTINJECTOR_MALLOC);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(nPending));
  return TCL_OK;
}


/*
** Usage:    sqlite3_memdebug_settitle TITLE

  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "BOOLEAN");
    return TCL_ERROR;
  }
  if( TCL_OK!=Tcl_GetBooleanFromObj(interp, objv[1], &isInstall) ){
    return TCL_ERROR;
  }
  rc = sqlite3_test_control(SQLITE_TESTCTRL_FAULT_INSTALL, isInstall);
  Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_VOLATILE);
  return TCL_OK;
}

/*
** Register commands with the TCL interpreter.
*/

  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
  }
  return TCL_OK;
}