test_malloc.c

最新的sqlite3.6.2源代码

/*
** 2007 August 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.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.47 2008/08/05 17:53:24 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

/*
** This structure is used to encapsulate the global state variables used 
** by malloc() fault simulation.
*/
static struct MemFault {
  int iCountdown;         /* Number of pending successes before 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 */
  int isInstalled;        /* True if the fault simulation layer is installed */
  int isBenignMode;       /* True if malloc failures are considered benign */
  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.isBenignMode>0 ){
    memfault.nBenign++;
  }
  memfault.nRepeat--;
  if( memfault.nRepeat<=0 ){
    memfault.enable = 0;
  }
  return 1;  
}

/*
** A version of sqlite3_mem_methods.xMalloc() that includes fault simulation
** logic.
*/
static void *faultsimMalloc(int n){
  void *p = 0;
  if( !faultsimStep() ){
    p = memfault.m.xMalloc(n);
  }
  return p;
}


/*
** A version of sqlite3_mem_methods.xRealloc() that includes fault simulation
** logic.
*/
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 the malloc failure simulation.  After
** calling this routine, the next nDelay mallocs will succeed, followed
** by a block of nRepeat failures, after which malloc() calls will begin
** to succeed again.
*/
static void faultsimConfig(int nDelay, int nRepeat){
  memfault.iCountdown = nDelay;
  memfault.nRepeat = nRepeat;
  memfault.nBenign = 0;
  memfault.nFail = 0;
  memfault.enable = nDelay>=0;
}

/*
** Return the number of faults (both hard and benign faults) that have
** occurred since the injector was last configured.
*/
static int faultsimFailures(void){
  return memfault.nFail;
}

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

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


static void faultsimBeginBenign(void){
  memfault.isBenignMode++;
}
static void faultsimEndBenign(void){
  memfault.isBenignMode--;
}

/*
** Add or remove the fault-simulation layer using sqlite3_config(). If
** the argument is non-zero, the 
*/
static int faultsimInstall(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;

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

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

  if( install ){
    rc = sqlite3_config(SQLITE_CONFIG_GETMALLOC, &memfault.m);
    assert(memfault.m.xMalloc);
    if( rc==SQLITE_OK ){
      rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &m);
    }
    sqlite3_test_control(SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS, 
        faultsimBeginBenign, faultsimEndBenign
    );
  }else{
    assert(memfault.m.xMalloc);
    rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &memfault.m);
    sqlite3_test_control(SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS, 0, 0);
  }

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

#ifdef SQLITE_TEST

/*
** This function is implemented in test1.c. Returns a pointer to a static
** buffer containing the symbolic SQLite error code that corresponds to
** the least-significant 8-bits of the integer passed as an argument.
** For example:
**
**   sqlite3TestErrorName(1) -> "SQLITE_ERROR"
*/
const char *sqlite3TestErrorName(int);

/*
** Transform pointers to text and back again
*/
static void pointerToText(void *p, char *z){
  static const char zHex[] = "0123456789abcdef";
  int i, k;
  unsigned int u;
  sqlite3_uint64 n;
  if( p==0 ){
    strcpy(z, "0");
    return;
  }
  if( sizeof(n)==sizeof(p) ){
    memcpy(&n, &p, sizeof(p));
  }else if( sizeof(u)==sizeof(p) ){
    memcpy(&u, &p, sizeof(u));
    n = u;
  }else{
    assert( 0 );
  }
  for(i=0, k=sizeof(p)*2-1; i<sizeof(p)*2; i++, k--){
    z[k] = zHex[n&0xf];
    n >>= 4;
  }
  z[sizeof(p)*2] = 0;
}
static int hexToInt(int h){
  if( h>='0' && h<='9' ){
    return h - '0';
  }else if( h>='a' && h<='f' ){
    return h - 'a' + 10;
  }else{
    return -1;
  }
}
static int textToPointer(const char *z, void **pp){
  sqlite3_uint64 n = 0;
  int i;
  unsigned int u;
  for(i=0; i<sizeof(void*)*2 && z[0]; i++){
    int v;
    v = hexToInt(*z++);
    if( v<0 ) return TCL_ERROR;
    n = n*16 + v;
  }
  if( *z!=0 ) return TCL_ERROR;
  if( sizeof(n)==sizeof(*pp) ){
    memcpy(pp, &n, sizeof(n));
  }else if( sizeof(u)==sizeof(*pp) ){
    u = (unsigned int)n;
    memcpy(pp, &u, sizeof(u));
  }else{
    assert( 0 );
  }
  return TCL_OK;
}

/*
** Usage:    sqlite3_malloc  NBYTES
**
** Raw test interface for sqlite3_malloc().
*/
static int test_malloc(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int nByte;
  void *p;
  char zOut[100];
  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "NBYTES");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[1], &nByte) ) return TCL_ERROR;
  p = sqlite3_malloc((unsigned)nByte);
  pointerToText(p, zOut);
  Tcl_AppendResult(interp, zOut, NULL);
  return TCL_OK;
}

/*
** Usage:    sqlite3_realloc  PRIOR  NBYTES
**
** Raw test interface for sqlite3_realloc().
*/
static int test_realloc(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int nByte;
  void *pPrior, *p;
  char zOut[100];
  if( objc!=3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "PRIOR NBYTES");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &nByte) ) return TCL_ERROR;
  if( textToPointer(Tcl_GetString(objv[1]), &pPrior) ){
    Tcl_AppendResult(interp, "bad pointer: ", Tcl_GetString(objv[1]), (char*)0);
    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(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  void *pPrior;
  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "PRIOR");
    return TCL_ERROR;
  }
  if( textToPointer(Tcl_GetString(objv[1]), &pPrior) ){
    Tcl_AppendResult(interp, "bad pointer: ", Tcl_GetString(objv[1]), (char*)0);
    return TCL_ERROR;
  }
  sqlite3_free(pPrior);
  return TCL_OK;
}

/*
** These routines are in test_hexio.c
*/
int sqlite3TestHexToBin(const char *, int, char *);
int sqlite3TestBinToHex(char*,int);

/*
** Usage:    memset  ADDRESS  SIZE  HEX
**
** Set a chunk of memory (obtained from malloc, probably) to a
** specified hex pattern.
*/
static int test_memset(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  void *p;
  int size, n, i;
  char *zHex;
  char *zOut;
  char zBin[100];

  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "ADDRESS SIZE HEX");
    return TCL_ERROR;
  }
  if( textToPointer(Tcl_GetString(objv[1]), &p) ){
    Tcl_AppendResult(interp, "bad pointer: ", Tcl_GetString(objv[1]), (char*)0);
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &size) ){
    return TCL_ERROR;
  }
  if( size<=0 ){
    Tcl_AppendResult(interp, "size must be positive", (char*)0);
    return TCL_ERROR;
  }
  zHex = Tcl_GetStringFromObj(objv[3], &n);
  if( n>sizeof(zBin)*2 ) n = sizeof(zBin)*2;
  n = sqlite3TestHexToBin(zHex, n, zBin);
  if( n==0 ){
    Tcl_AppendResult(interp, "no data", (char*)0);
    return TCL_ERROR;
  }
  zOut = p;
  for(i=0; i<size; i++){
    zOut[i] = zBin[i%n];
  }
  return TCL_OK;
}

/*
** Usage:    memget  ADDRESS  SIZE
**
** Return memory as hexadecimal text.
*/
static int test_memget(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  void *p;
  int size, n;
  char *zBin;
  char zHex[100];

  if( objc!=3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "ADDRESS SIZE");
    return TCL_ERROR;
  }
  if( textToPointer(Tcl_GetString(objv[1]), &p) ){
    Tcl_AppendResult(interp, "bad pointer: ", Tcl_GetString(objv[1]), (char*)0);
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &size) ){
    return TCL_ERROR;
  }
  if( size<=0 ){
    Tcl_AppendResult(interp, "size must be positive", (char*)0);
    return TCL_ERROR;