/*
** 2015-04-17
**
** 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 is a utility program designed to aid running the SQLite library
** against an external fuzzer, such as American Fuzzy Lop (AFL)
** (http://lcamtuf.coredump.cx/afl/).  Basically, this program reads
** SQL text from standard input and passes it through to SQLite for evaluation,
** just like the "sqlite3" command-line shell.  Differences from the
** command-line shell:
**
**    (1)  The complex "dot-command" extensions are omitted.  This
**         prevents the fuzzer from discovering that it can run things
**         like ".shell rm -rf ~"
**
**    (2)  The database is opened with the SQLITE_OPEN_MEMORY flag so that
**         no disk I/O from the database is permitted.  The ATTACH command
**         with a filename still uses an in-memory database.
**
**    (3)  The main in-memory database can be initialized from a template
**         disk database so that the fuzzer starts with a database containing
**         content.
**
**    (4)  The eval() SQL function is added, allowing the fuzzer to do 
**         interesting recursive operations.
**
**    (5)  An error is raised if there is a memory leak.
**
** The input text can be divided into separate test cases using comments
** of the form:
**
**       |****<...>****|
**
** where the "..." is arbitrary text. (Except the "|" should really be "/".
** "|" is used here to avoid compiler errors about nested comments.)
** A separate in-memory SQLite database is created to run each test case.
** This feature allows the "queue" of AFL to be captured into a single big
** file using a command like this:
**
**    (for i in id:*; do echo '|****<'$i'>****|'; cat $i; done) >~/all-queue.txt
**
** (Once again, change the "|" to "/") Then all elements of the AFL queue
** can be run in a single go (for regression testing, for example) by typing:
**
**    fuzzershell -f ~/all-queue.txt
**
** After running each chunk of SQL, the database connection is closed.  The
** program aborts if the close fails or if there is any unfreed memory after
** the close.
**
** New test cases can be appended to all-queue.txt at any time.  If redundant
** test cases are added, they can be eliminated by running:
**
**    fuzzershell -f ~/all-queue.txt --unique-cases ~/unique-cases.txt
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <ctype.h>
#include "sqlite3.h"
#define ISDIGIT(X) isdigit((unsigned char)(X))

/*
** All global variables are gathered into the "g" singleton.
*/
struct GlobalVars {
  const char *zArgv0;              /* Name of program */
  sqlite3_mem_methods sOrigMem;    /* Original memory methods */
  sqlite3_mem_methods sOomMem;     /* Memory methods with OOM simulator */
  int iOomCntdown;                 /* Memory fails on 1 to 0 transition */
  int nOomFault;                   /* Increments for each OOM fault */
  int bOomOnce;                    /* Fail just once if true */
  int bOomEnable;                  /* True to enable OOM simulation */
  int nOomBrkpt;                   /* Number of calls to oomFault() */
  char zTestName[100];             /* Name of current test */
} g;

/*
** Maximum number of iterations for an OOM test
*/
#ifndef OOM_MAX
# define OOM_MAX 625
#endif

/*
** This routine is called when a simulated OOM occurs.  It exists as a
** convenient place to set a debugger breakpoint.
*/
static void oomFault(void){
  g.nOomBrkpt++; /* Prevent oomFault() from being optimized out */
}


/* Versions of malloc() and realloc() that simulate OOM conditions */
static void *oomMalloc(int nByte){
  if( nByte>0 && g.bOomEnable && g.iOomCntdown>0 ){
    g.iOomCntdown--;
    if( g.iOomCntdown==0 ){
      if( g.nOomFault==0 ) oomFault();
      g.nOomFault++;
      if( !g.bOomOnce ) g.iOomCntdown = 1;
      return 0;
    }
  }
  return g.sOrigMem.xMalloc(nByte);
}
static void *oomRealloc(void *pOld, int nByte){
  if( nByte>0 && g.bOomEnable && g.iOomCntdown>0 ){
    g.iOomCntdown--;
    if( g.iOomCntdown==0 ){
      if( g.nOomFault==0 ) oomFault();
      g.nOomFault++;
      if( !g.bOomOnce ) g.iOomCntdown = 1;
      return 0;
    }
  }
  return g.sOrigMem.xRealloc(pOld, nByte);
}

/*
** Print an error message and abort in such a way to indicate to the
** fuzzer that this counts as a crash.
*/
static void abendError(const char *zFormat, ...){
  va_list ap;
  if( g.zTestName[0] ){
    fprintf(stderr, "%s (%s): ", g.zArgv0, g.zTestName);
  }else{
    fprintf(stderr, "%s: ", g.zArgv0);
  }
  va_start(ap, zFormat);
  vfprintf(stderr, zFormat, ap);
  va_end(ap);
  fprintf(stderr, "\n");
  abort();
}
/*
** Print an error message and quit, but not in a way that would look
** like a crash.
*/
static void fatalError(const char *zFormat, ...){
  va_list ap;
  if( g.zTestName[0] ){
    fprintf(stderr, "%s (%s): ", g.zArgv0, g.zTestName);
  }else{
    fprintf(stderr, "%s: ", g.zArgv0);
  }
  va_start(ap, zFormat);
  vfprintf(stderr, zFormat, ap);
  va_end(ap);
  fprintf(stderr, "\n");
  exit(1);
}

/*
** Evaluate some SQL.  Abort if unable.
*/
static void sqlexec(sqlite3 *db, const char *zFormat, ...){
  va_list ap;
  char *zSql;
  char *zErrMsg = 0;
  int rc;
  va_start(ap, zFormat);
  zSql = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  rc = sqlite3_exec(db, zSql, 0, 0, &zErrMsg);
  if( rc ) abendError("failed sql [%s]: %s", zSql, zErrMsg);
  sqlite3_free(zSql);
}

/*
** This callback is invoked by sqlite3_log().
*/
static void shellLog(void *pNotUsed, int iErrCode, const char *zMsg){
  printf("LOG: (%d) %s\n", iErrCode, zMsg);
  fflush(stdout);
}
static void shellLogNoop(void *pNotUsed, int iErrCode, const char *zMsg){
  return;
}

/*
** This callback is invoked by sqlite3_exec() to return query results.
*/
static int execCallback(void *NotUsed, int argc, char **argv, char **colv){
  int i;
  static unsigned cnt = 0;
  printf("ROW #%u:\n", ++cnt);
  if( argv ){
    for(i=0; i<argc; i++){
      printf(" %s=", colv[i]);
      if( argv[i] ){
        printf("[%s]\n", argv[i]);
      }else{
        printf("NULL\n");
      }
    }
  }
  fflush(stdout);
  return 0;
}
static int execNoop(void *NotUsed, int argc, char **argv, char **colv){
  return 0;
}

#ifndef SQLITE_OMIT_TRACE
/*
** This callback is invoked by sqlite3_trace() as each SQL statement
** starts.
*/
static void traceCallback(void *NotUsed, const char *zMsg){
  printf("TRACE: %s\n", zMsg);
  fflush(stdout);
}
static void traceNoop(void *NotUsed, const char *zMsg){
  return;
}
#endif

/***************************************************************************
** eval() implementation copied from ../ext/misc/eval.c
*/
/*
** Structure used to accumulate the output
*/
struct EvalResult {
  char *z;               /* Accumulated output */
  const char *zSep;      /* Separator */
  int szSep;             /* Size of the separator string */
  sqlite3_int64 nAlloc;  /* Number of bytes allocated for z[] */
  sqlite3_int64 nUsed;   /* Number of bytes of z[] actually used */
};

/*
** Callback from sqlite_exec() for the eval() function.
*/
static int callback(void *pCtx, int argc, char **argv, char **colnames){
  struct EvalResult *p = (struct EvalResult*)pCtx;
  int i; 
  for(i=0; i<argc; i++){
    const char *z = argv[i] ? argv[i] : "";
    size_t sz = strlen(z);
    if( (sqlite3_int64)sz+p->nUsed+p->szSep+1 > p->nAlloc ){
      char *zNew;
      p->nAlloc = p->nAlloc*2 + sz + p->szSep + 1;
      /* Using sqlite3_realloc64() would be better, but it is a recent
      ** addition and will cause a segfault if loaded by an older version
      ** of SQLite.  */
      zNew = p->nAlloc<=0x7fffffff ? sqlite3_realloc(p->z, (int)p->nAlloc) : 0;
      if( zNew==0 ){
        sqlite3_free(p->z);
        memset(p, 0, sizeof(*p));
        return 1;
      }
      p->z = zNew;
    }
    if( p->nUsed>0 ){
      memcpy(&p->z[p->nUsed], p->zSep, p->szSep);
      p->nUsed += p->szSep;
    }
    memcpy(&p->z[p->nUsed], z, sz);
    p->nUsed += sz;
  }
  return 0;
}

/*
** Implementation of the eval(X) and eval(X,Y) SQL functions.
**
** Evaluate the SQL text in X.  Return the results, using string
** Y as the separator.  If Y is omitted, use a single space character.
*/
static void sqlEvalFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const char *zSql;
  sqlite3 *db;
  char *zErr = 0;
  int rc;
  struct EvalResult x;

  memset(&x, 0, sizeof(x));
  x.zSep = " ";
  zSql = (const char*)sqlite3_value_text(argv[0]);
  if( zSql==0 ) return;
  if( argc>1 ){
    x.zSep = (const char*)sqlite3_value_text(argv[1]);
    if( x.zSep==0 ) return;
  }
  x.szSep = (int)strlen(x.zSep);
  db = sqlite3_context_db_handle(context);
  rc = sqlite3_exec(db, zSql, callback, &x, &zErr);
  if( rc!=SQLITE_OK ){
    sqlite3_result_error(context, zErr, -1);
    sqlite3_free(zErr);
  }else if( x.zSep==0 ){
    sqlite3_result_error_nomem(context);
    sqlite3_free(x.z);
  }else{
    sqlite3_result_text(context, x.z, (int)x.nUsed, sqlite3_free);
  }
}
/* End of the eval() implementation
******************************************************************************/

/******************************************************************************
** The generate_series(START,END,STEP) eponymous table-valued function.
**
** This code is copy/pasted from ext/misc/series.c in the SQLite source tree.
*/
/* series_cursor is a subclass of sqlite3_vtab_cursor which will
** serve as the underlying representation of a cursor that scans
** over rows of the result
*/
typedef struct series_cursor series_cursor;
struct series_cursor {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  int isDesc;                /* True to count down rather than up */
  sqlite3_int64 iRowid;      /* The rowid */
  sqlite3_int64 iValue;      /* Current value ("value") */
  sqlite3_int64 mnValue;     /* Mimimum value ("start") */
  sqlite3_int64 mxValue;     /* Maximum value ("stop") */
  sqlite3_int64 iStep;       /* Increment ("step") */
};

/*
** The seriesConnect() method is invoked to create a new
** series_vtab that describes the generate_series virtual table.
**
** Think of this routine as the constructor for series_vtab objects.
**
** All this routine needs to do is:
**
**    (1) Allocate the series_vtab object and initialize all fields.
**
**    (2) Tell SQLite (via the sqlite3_declare_vtab() interface) what the
**        result set of queries against generate_series will look like.
*/
static int seriesConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  sqlite3_vtab *pNew;
  int rc;

/* Column numbers */
#define SERIES_COLUMN_VALUE 0
#define SERIES_COLUMN_START 1
#define SERIES_COLUMN_STOP  2
#define SERIES_COLUMN_STEP  3

  rc = sqlite3_declare_vtab(db,
     "CREATE TABLE x(value,start hidden,stop hidden,step hidden)");
  if( rc==SQLITE_OK ){
    pNew = *ppVtab = sqlite3_malloc( sizeof(*pNew) );
    if( pNew==0 ) return SQLITE_NOMEM;
    memset(pNew, 0, sizeof(*pNew));
  }
  return rc;
}

/*
** This method is the destructor for series_cursor objects.
*/
static int seriesDisconnect(sqlite3_vtab *pVtab){
  sqlite3_free(pVtab);
  return SQLITE_OK;
}

/*
** Constructor for a new series_cursor object.
*/
static int seriesOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
  series_cursor *pCur;
  pCur = sqlite3_malloc( sizeof(*pCur) );
  if( pCur==0 ) return SQLITE_NOMEM;
  memset(pCur, 0, sizeof(*pCur));
  *ppCursor = &pCur->base;
  return SQLITE_OK;
}

/*
** Destructor for a series_cursor.
*/
static int seriesClose(sqlite3_vtab_cursor *cur){
  sqlite3_free(cur);
  return SQLITE_OK;
}


/*
** Advance a series_cursor to its next row of output.
*/
static int seriesNext(sqlite3_vtab_cursor *cur){
  series_cursor *pCur = (series_cursor*)cur;
  if( pCur->isDesc ){
    pCur->iValue -= pCur->iStep;
  }else{
    pCur->iValue += pCur->iStep;
  }
  pCur->iRowid++;
  return SQLITE_OK;
}

/*
** Return values of columns for the row at which the series_cursor
** is currently pointing.
*/
static int seriesColumn(
  sqlite3_vtab_cursor *cur,   /* The cursor */
  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
  int i                       /* Which column to return */
){
  series_cursor *pCur = (series_cursor*)cur;
  sqlite3_int64 x = 0;
  switch( i ){
    case SERIES_COLUMN_START:  x = pCur->mnValue; break;
    case SERIES_COLUMN_STOP:   x = pCur->mxValue; break;
    case SERIES_COLUMN_STEP:   x = pCur->iStep;   break;
    default:                   x = pCur->iValue;  break;
  }
  sqlite3_result_int64(ctx, x);
  return SQLITE_OK;
}

/*
** Return the rowid for the current row.  In this implementation, the
** rowid is the same as the output value.
*/
static int seriesRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  series_cursor *pCur = (series_cursor*)cur;
  *pRowid = pCur->iRowid;
  return SQLITE_OK;
}

/*
** Return TRUE if the cursor has been moved off of the last
** row of output.
*/
static int seriesEof(sqlite3_vtab_cursor *cur){
  series_cursor *pCur = (series_cursor*)cur;
  if( pCur->isDesc ){
    return pCur->iValue < pCur->mnValue;
  }else{
    return pCur->iValue > pCur->mxValue;
  }
}

/* True to cause run-time checking of the start=, stop=, and/or step= 
** parameters.  The only reason to do this is for testing the
** constraint checking logic for virtual tables in the SQLite core.
*/
#ifndef SQLITE_SERIES_CONSTRAINT_VERIFY
# define SQLITE_SERIES_CONSTRAINT_VERIFY 0
#endif

/*
** This method is called to "rewind" the series_cursor object back
** to the first row of output.  This method is always called at least
** once prior to any call to seriesColumn() or seriesRowid() or 
** seriesEof().
**
** The query plan selected by seriesBestIndex is passed in the idxNum
** parameter.  (idxStr is not used in this implementation.)  idxNum
** is a bitmask showing which constraints are available:
**
**    1:    start=VALUE
**    2:    stop=VALUE
**    4:    step=VALUE
**
** Also, if bit 8 is set, that means that the series should be output
** in descending order rather than in ascending order.
**
** This routine should initialize the cursor and position it so that it
** is pointing at the first row, or pointing off the end of the table
** (so that seriesEof() will return true) if the table is empty.
*/
static int seriesFilter(
  sqlite3_vtab_cursor *pVtabCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  series_cursor *pCur = (series_cursor *)pVtabCursor;
  int i = 0;
  if( idxNum & 1 ){
    pCur->mnValue = sqlite3_value_int64(argv[i++]);
  }else{
    pCur->mnValue = 0;
  }
  if( idxNum & 2 ){
    pCur->mxValue = sqlite3_value_int64(argv[i++]);
  }else{
    pCur->mxValue = 0xffffffff;
  }
  if( idxNum & 4 ){
    pCur->iStep = sqlite3_value_int64(argv[i++]);
    if( pCur->iStep<1 ) pCur->iStep = 1;
  }else{
    pCur->iStep = 1;
  }
  if( idxNum & 8 ){
    pCur->isDesc = 1;
    pCur->iValue = pCur->mxValue;
    if( pCur->iStep>0 ){
      pCur->iValue -= (pCur->mxValue - pCur->mnValue)%pCur->iStep;
    }
  }else{
    pCur->isDesc = 0;
    pCur->iValue = pCur->mnValue;
  }
  pCur->iRowid = 1;
  return SQLITE_OK;
}

/*
** SQLite will invoke this method one or more times while planning a query
** that uses the generate_series virtual table.  This routine needs to create
** a query plan for each invocation and compute an estimated cost for that
** plan.
**
** In this implementation idxNum is used to represent the
** query plan.  idxStr is unused.
**
** The query plan is represented by bits in idxNum:
**
**  (1)  start = $value  -- constraint exists
**  (2)  stop = $value   -- constraint exists
**  (4)  step = $value   -- constraint exists
**  (8)  output in descending order
*/
static int seriesBestIndex(
  sqlite3_vtab *tab,
  sqlite3_index_info *pIdxInfo
){
  int i;                 /* Loop over constraints */
  int idxNum = 0;        /* The query plan bitmask */
  int startIdx = -1;     /* Index of the start= constraint, or -1 if none */
  int stopIdx = -1;      /* Index of the stop= constraint, or -1 if none */
  int stepIdx = -1;      /* Index of the step= constraint, or -1 if none */
  int nArg = 0;          /* Number of arguments that seriesFilter() expects */

  const struct sqlite3_index_constraint *pConstraint;
  pConstraint = pIdxInfo->aConstraint;
  for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
    if( pConstraint->usable==0 ) continue;
    if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
    switch( pConstraint->iColumn ){
      case SERIES_COLUMN_START:
        startIdx = i;
        idxNum |= 1;
        break;
      case SERIES_COLUMN_STOP:
        stopIdx = i;
        idxNum |= 2;
        break;
      case SERIES_COLUMN_STEP:
        stepIdx = i;
        idxNum |= 4;
        break;
    }
  }
  if( startIdx>=0 ){
    pIdxInfo->aConstraintUsage[startIdx].argvIndex = ++nArg;
    pIdxInfo->aConstraintUsage[startIdx].omit= !SQLITE_SERIES_CONSTRAINT_VERIFY;
  }
  if( stopIdx>=0 ){
    pIdxInfo->aConstraintUsage[stopIdx].argvIndex = ++nArg;
    pIdxInfo->aConstraintUsage[stopIdx].omit = !SQLITE_SERIES_CONSTRAINT_VERIFY;
  }
  if( stepIdx>=0 ){
    pIdxInfo->aConstraintUsage[stepIdx].argvIndex = ++nArg;
    pIdxInfo->aConstraintUsage[stepIdx].omit = !SQLITE_SERIES_CONSTRAINT_VERIFY;
  }
  if( (idxNum & 3)==3 ){
    /* Both start= and stop= boundaries are available.  This is the 
    ** the preferred case */
    pIdxInfo->estimatedCost = (double)(2 - ((idxNum&4)!=0));
    pIdxInfo->estimatedRows = 1000;
    if( pIdxInfo->nOrderBy==1 ){
      if( pIdxInfo->aOrderBy[0].desc ) idxNum |= 8;
      pIdxInfo->orderByConsumed = 1;
    }
  }else{
    /* If either boundary is missing, we have to generate a huge span
    ** of numbers.  Make this case very expensive so that the query
    ** planner will work hard to avoid it. */
    pIdxInfo->estimatedCost = (double)2147483647;
    pIdxInfo->estimatedRows = 2147483647;
  }
  pIdxInfo->idxNum = idxNum;
  return SQLITE_OK;
}

/*
** This following structure defines all the methods for the 
** generate_series virtual table.
*/
static sqlite3_module seriesModule = {
  0,                         /* iVersion */
  0,                         /* xCreate */
  seriesConnect,             /* xConnect */
  seriesBestIndex,           /* xBestIndex */
  seriesDisconnect,          /* xDisconnect */
  0,                         /* xDestroy */
  seriesOpen,                /* xOpen - open a cursor */
  seriesClose,               /* xClose - close a cursor */
  seriesFilter,              /* xFilter - configure scan constraints */
  seriesNext,                /* xNext - advance a cursor */
  seriesEof,                 /* xEof - check for end of scan */
  seriesColumn,              /* xColumn - read data */
  seriesRowid,               /* xRowid - read data */
  0,                         /* xUpdate */
  0,                         /* xBegin */
  0,                         /* xSync */
  0,                         /* xCommit */
  0,                         /* xRollback */
  0,                         /* xFindMethod */
  0,                         /* xRename */
};
/* END the generate_series(START,END,STEP) implementation
*********************************************************************************/

/*
** Print sketchy documentation for this utility program
*/
static void showHelp(void){
  printf("Usage: %s [options] ?FILE...?\n", g.zArgv0);
  printf(
"Read SQL text from FILE... (or from standard input if FILE... is omitted)\n"
"and then evaluate each block of SQL contained therein.\n"
"Options:\n"
"  --autovacuum          Enable AUTOVACUUM mode\n"
"  --database FILE       Use database FILE instead of an in-memory database\n"
"  --disable-lookaside   Turn off lookaside memory\n"
"  --heap SZ MIN         Memory allocator uses SZ bytes & min allocation MIN\n"
"  --help                Show this help text\n"    
"  --lookaside N SZ      Configure lookaside for N slots of SZ bytes each\n"
"  --oom                 Run each test multiple times in a simulated OOM loop\n"
"  --pagesize N          Set the page size to N\n"
"  --pcache N SZ         Configure N pages of pagecache each of size SZ bytes\n"
"  -q                    Reduced output\n"
"  --quiet               Reduced output\n"
"  --scratch N SZ        Configure scratch memory for N slots of SZ bytes each\n"
"  --unique-cases FILE   Write all unique test cases to FILE\n"
"  --utf16be             Set text encoding to UTF-16BE\n"
"  --utf16le             Set text encoding to UTF-16LE\n"
"  -v                    Increased output\n"
"  --verbose             Increased output\n"
  );
}

/*
** Return the value of a hexadecimal digit.  Return -1 if the input
** is not a hex digit.
*/
static int hexDigitValue(char c){
  if( c>='0' && c<='9' ) return c - '0';
  if( c>='a' && c<='f' ) return c - 'a' + 10;
  if( c>='A' && c<='F' ) return c - 'A' + 10;
  return -1;
}

/*
** Interpret zArg as an integer value, possibly with suffixes.
*/
static int integerValue(const char *zArg){
  sqlite3_int64 v = 0;
  static const struct { char *zSuffix; int iMult; } aMult[] = {
    { "KiB", 1024 },
    { "MiB", 1024*1024 },
    { "GiB", 1024*1024*1024 },
    { "KB",  1000 },
    { "MB",  1000000 },
    { "GB",  1000000000 },
    { "K",   1000 },
    { "M",   1000000 },
    { "G",   1000000000 },
  };
  int i;
  int isNeg = 0;
  if( zArg[0]=='-' ){
    isNeg = 1;
    zArg++;
  }else if( zArg[0]=='+' ){
    zArg++;
  }
  if( zArg[0]=='0' && zArg[1]=='x' ){
    int x;
    zArg += 2;
    while( (x = hexDigitValue(zArg[0]))>=0 ){
      v = (v<<4) + x;
      zArg++;
    }
  }else{
    while( ISDIGIT(zArg[0]) ){
      v = v*10 + zArg[0] - '0';
      zArg++;
    }
  }
  for(i=0; i<sizeof(aMult)/sizeof(aMult[0]); i++){
    if( sqlite3_stricmp(aMult[i].zSuffix, zArg)==0 ){
      v *= aMult[i].iMult;
      break;
    }
  }
  if( v>0x7fffffff ) abendError("parameter too large - max 2147483648");
  return (int)(isNeg? -v : v);
}

/* Return the current wall-clock time */
static sqlite3_int64 timeOfDay(void){
  static sqlite3_vfs *clockVfs = 0;
  sqlite3_int64 t;
  if( clockVfs==0 ) clockVfs = sqlite3_vfs_find(0);
  if( clockVfs->iVersion>=1 && clockVfs->xCurrentTimeInt64!=0 ){
    clockVfs->xCurrentTimeInt64(clockVfs, &t);
  }else{
    double r;
    clockVfs->xCurrentTime(clockVfs, &r);
    t = (sqlite3_int64)(r*86400000.0);
  }
  return t;
}

int main(int argc, char **argv){
  char *zIn = 0;                /* Input text */
  int nAlloc = 0;               /* Number of bytes allocated for zIn[] */
  int nIn = 0;                  /* Number of bytes of zIn[] used */
  size_t got;                   /* Bytes read from input */
  int rc = SQLITE_OK;           /* Result codes from API functions */
  int i;                        /* Loop counter */
  int iNext;                    /* Next block of SQL */
  sqlite3 *db;                  /* Open database */
  char *zErrMsg = 0;            /* Error message returned from sqlite3_exec() */
  const char *zEncoding = 0;    /* --utf16be or --utf16le */
  int nHeap = 0, mnHeap = 0;    /* Heap size from --heap */
  int nLook = 0, szLook = 0;    /* --lookaside configuration */
  int nPCache = 0, szPCache = 0;/* --pcache configuration */
  int nScratch = 0, szScratch=0;/* --scratch configuration */
  int pageSize = 0;             /* Desired page size.  0 means default */
  void *pHeap = 0;              /* Allocated heap space */
  void *pLook = 0;              /* Allocated lookaside space */
  void *pPCache = 0;            /* Allocated storage for pcache */
  void *pScratch = 0;           /* Allocated storage for scratch */
  int doAutovac = 0;            /* True for --autovacuum */
  char *zSql;                   /* SQL to run */
  char *zToFree = 0;            /* Call sqlite3_free() on this afte running zSql */
  int verboseFlag = 0;          /* --verbose or -v flag */
  int quietFlag = 0;            /* --quiet or -q flag */
  int nTest = 0;                /* Number of test cases run */
  int multiTest = 0;            /* True if there will be multiple test cases */
  int lastPct = -1;             /* Previous percentage done output */
  sqlite3 *dataDb = 0;          /* Database holding compacted input data */
  sqlite3_stmt *pStmt = 0;      /* Statement to insert testcase into dataDb */
  const char *zDataOut = 0;     /* Write compacted data to this output file */
  int nHeader = 0;              /* Bytes of header comment text on input file */
  int oomFlag = 0;              /* --oom */
  int oomCnt = 0;               /* Counter for the OOM loop */
  char zErrBuf[200];            /* Space for the error message */
  const char *zFailCode;        /* Value of the TEST_FAILURE environment var */
  const char *zPrompt;          /* Initial prompt when large-file fuzzing */
  int nInFile = 0;              /* Number of input files to read */
  char **azInFile = 0;          /* Array of input file names */
  int jj;                       /* Loop counter for azInFile[] */
  sqlite3_int64 iBegin;         /* Start time for the whole program */
  sqlite3_int64 iStart, iEnd;   /* Start and end-times for a test case */
  const char *zDbName = 0;      /* Name of an on-disk database file to open */

  iBegin = timeOfDay();
  sqlite3_shutdown();
  zFailCode = getenv("TEST_FAILURE");
  g.zArgv0 = argv[0];
  zPrompt = "<stdin>";
  for(i=1; i<argc; i++){
    const char *z = argv[i];
    if( z[0]=='-' ){
      z++;
      if( z[0]=='-' ) z++;
      if( strcmp(z,"autovacuum")==0 ){
        doAutovac = 1;
      }else
      if( strcmp(z,"database")==0 ){
        if( i>=argc-1 ) abendError("missing argument on %s\n", argv[i]);
        zDbName = argv[i+1];
        i += 1;
      }else
      if( strcmp(z,"disable-lookaside")==0 ){
        nLook = 1;
        szLook = 0;
      }else
      if( strcmp(z, "f")==0 && i+1<argc ){
        i++;
        goto addNewInFile;
      }else
      if( strcmp(z,"heap")==0 ){
        if( i>=argc-2 ) abendError("missing arguments on %s\n", argv[i]);
        nHeap = integerValue(argv[i+1]);
        mnHeap = integerValue(argv[i+2]);
        i += 2;
      }else
      if( strcmp(z,"help")==0 ){
        showHelp();
        return 0;
      }else
      if( strcmp(z,"lookaside")==0 ){
        if( i>=argc-2 ) abendError("missing arguments on %s", argv[i]);
        nLook = integerValue(argv[i+1]);
        szLook = integerValue(argv[i+2]);
        i += 2;
      }else
      if( strcmp(z,"oom")==0 ){
        oomFlag = 1;
      }else
      if( strcmp(z,"pagesize")==0 ){
        if( i>=argc-1 ) abendError("missing argument on %s", argv[i]);
        pageSize = integerValue(argv[++i]);
      }else
      if( strcmp(z,"pcache")==0 ){
        if( i>=argc-2 ) abendError("missing arguments on %s", argv[i]);
        nPCache = integerValue(argv[i+1]);
        szPCache = integerValue(argv[i+2]);
        i += 2;
      }else
      if( strcmp(z,"quiet")==0 || strcmp(z,"q")==0 ){
        quietFlag = 1;
        verboseFlag = 0;
      }else
      if( strcmp(z,"scratch")==0 ){
        if( i>=argc-2 ) abendError("missing arguments on %s", argv[i]);
        nScratch = integerValue(argv[i+1]);
        szScratch = integerValue(argv[i+2]);
        i += 2;
      }else
      if( strcmp(z, "unique-cases")==0 ){
        if( i>=argc-1 ) abendError("missing arguments on %s", argv[i]);
        if( zDataOut ) abendError("only one --minimize allowed");
        zDataOut = argv[++i];
      }else
      if( strcmp(z,"utf16le")==0 ){
        zEncoding = "utf16le";
      }else
      if( strcmp(z,"utf16be")==0 ){
        zEncoding = "utf16be";
      }else
      if( strcmp(z,"verbose")==0 || strcmp(z,"v")==0 ){
        quietFlag = 0;
        verboseFlag = 1;
      }else
      {
        abendError("unknown option: %s", argv[i]);
      }
    }else{
      addNewInFile:
      nInFile++;
      azInFile = realloc(azInFile, sizeof(azInFile[0])*nInFile);
      if( azInFile==0 ) abendError("out of memory");
      azInFile[nInFile-1] = argv[i];
    }
  }

  /* Do global SQLite initialization */
  sqlite3_config(SQLITE_CONFIG_LOG, verboseFlag ? shellLog : shellLogNoop, 0);
  if( nHeap>0 ){
    pHeap = malloc( nHeap );
    if( pHeap==0 ) fatalError("cannot allocate %d-byte heap\n", nHeap);
    rc = sqlite3_config(SQLITE_CONFIG_HEAP, pHeap, nHeap, mnHeap);
    if( rc ) abendError("heap configuration failed: %d\n", rc);
  }
  if( oomFlag ){
    sqlite3_config(SQLITE_CONFIG_GETMALLOC, &g.sOrigMem);
    g.sOomMem = g.sOrigMem;
    g.sOomMem.xMalloc = oomMalloc;
    g.sOomMem.xRealloc = oomRealloc;
    sqlite3_config(SQLITE_CONFIG_MALLOC, &g.sOomMem);
  }
  if( nLook>0 ){
    sqlite3_config(SQLITE_CONFIG_LOOKASIDE, 0, 0);
    if( szLook>0 ){
      pLook = malloc( nLook*szLook );
      if( pLook==0 ) fatalError("out of memory");
    }
  }
  if( nScratch>0 && szScratch>0 ){
    pScratch = malloc( nScratch*(sqlite3_int64)szScratch );
    if( pScratch==0 ) fatalError("cannot allocate %lld-byte scratch",
                                 nScratch*(sqlite3_int64)szScratch);
    rc = sqlite3_config(SQLITE_CONFIG_SCRATCH, pScratch, szScratch, nScratch);
    if( rc ) abendError("scratch configuration failed: %d\n", rc);
  }
  if( nPCache>0 && szPCache>0 ){
    pPCache = malloc( nPCache*(sqlite3_int64)szPCache );
    if( pPCache==0 ) fatalError("cannot allocate %lld-byte pcache",
                                 nPCache*(sqlite3_int64)szPCache);
    rc = sqlite3_config(SQLITE_CONFIG_PAGECACHE, pPCache, szPCache, nPCache);
    if( rc ) abendError("pcache configuration failed: %d", rc);
  }

  /* If the --unique-cases option was supplied, open the database that will
  ** be used to gather unique test cases.
  */
  if( zDataOut ){
    rc = sqlite3_open(":memory:", &dataDb);
    if( rc ) abendError("cannot open :memory: database");
    rc = sqlite3_exec(dataDb,
          "CREATE TABLE testcase(sql BLOB PRIMARY KEY, tm) WITHOUT ROWID;",0,0,0);
    if( rc ) abendError("%s", sqlite3_errmsg(dataDb));
    rc = sqlite3_prepare_v2(dataDb,
          "INSERT OR IGNORE INTO testcase(sql,tm)VALUES(?1,?2)",
          -1, &pStmt, 0);
    if( rc ) abendError("%s", sqlite3_errmsg(dataDb));
  }

  /* Initialize the input buffer used to hold SQL text */
  if( nInFile==0 ) nInFile = 1;
  nAlloc = 1000;
  zIn = malloc(nAlloc);
  if( zIn==0 ) fatalError("out of memory");

  /* Loop over all input files */
  for(jj=0; jj<nInFile; jj++){

    /* Read the complete content of the next input file into zIn[] */
    FILE *in;
    if( azInFile ){
      int j, k;
      in = fopen(azInFile[jj],"rb");
      if( in==0 ){
        abendError("cannot open %s for reading", azInFile[jj]);
      }
      zPrompt = azInFile[jj];
      for(j=k=0; zPrompt[j]; j++) if( zPrompt[j]=='/' ) k = j+1;
      zPrompt += k;
    }else{
      in = stdin;
      zPrompt = "<stdin>";
    }
    while( !feof(in) ){
      got = fread(zIn+nIn, 1, nAlloc-nIn-1, in); 
      nIn += (int)got;
      zIn[nIn] = 0;
      if( got==0 ) break;
      if( nAlloc - nIn - 1 < 100 ){
        nAlloc += nAlloc+1000;
        zIn = realloc(zIn, nAlloc);
        if( zIn==0 ) fatalError("out of memory");
      }
    }
    if( in!=stdin ) fclose(in);
    lastPct = -1;

    /* Skip initial lines of the input file that begin with "#" */
    for(i=0; i<nIn; i=iNext+1){
      if( zIn[i]!='#' ) break;
      for(iNext=i+1; iNext<nIn && zIn[iNext]!='\n'; iNext++){}
    }
    nHeader = i;

    /* Process all test cases contained within the input file.
    */
    for(; i<nIn; i=iNext, nTest++, g.zTestName[0]=0){
      char cSaved;
      if( strncmp(&zIn[i], "/****<",6)==0 ){
        char *z = strstr(&zIn[i], ">****/");
        if( z ){
          z += 6;
          sqlite3_snprintf(sizeof(g.zTestName), g.zTestName, "%.*s", 
                           (int)(z-&zIn[i]) - 12, &zIn[i+6]);
          if( verboseFlag ){
            printf("%.*s\n", (int)(z-&zIn[i]), &zIn[i]);
            fflush(stdout);
          }
          i += (int)(z-&zIn[i]);
          multiTest = 1;
        }
      }
      for(iNext=i; iNext<nIn && strncmp(&zIn[iNext],"/****<",6)!=0; iNext++){}
      cSaved = zIn[iNext];
      zIn[iNext] = 0;


      /* Print out the SQL of the next test case is --verbose is enabled
      */
      zSql = &zIn[i];
      if( verboseFlag ){
        printf("INPUT (offset: %d, size: %d): [%s]\n",
                i, (int)strlen(&zIn[i]), &zIn[i]);
      }else if( multiTest && !quietFlag ){
        if( oomFlag ){
          printf("%s\n", g.zTestName);
        }else{
          int pct = (10*iNext)/nIn;
          if( pct!=lastPct ){
            if( lastPct<0 ) printf("%s:", zPrompt);
            printf(" %d%%", pct*10);
            lastPct = pct;
          }
        }
      }else if( nInFile>1 ){
        printf("%s\n", zPrompt);
      }
      fflush(stdout);

      /* Run the next test case.  Run it multiple times in --oom mode
      */
      if( oomFlag ){
        oomCnt = g.iOomCntdown = 1;
        g.nOomFault = 0;
        g.bOomOnce = 1;
        if( verboseFlag ){
          printf("Once.%d\n", oomCnt);
          fflush(stdout);
        }
      }else{
        oomCnt = 0;
      }
      do{
        if( zDbName ){
          rc = sqlite3_open_v2(zDbName, &db, SQLITE_OPEN_READWRITE, 0);
          if( rc!=SQLITE_OK ){
            abendError("Cannot open database file %s", zDbName);
          }
        }else{
          rc = sqlite3_open_v2(
            "main.db", &db,
            SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_MEMORY,
            0);
          if( rc!=SQLITE_OK ){
            abendError("Unable to open the in-memory database");
          }
        }
        if( pLook ){
          rc = sqlite3_db_config(db, SQLITE_DBCONFIG_LOOKASIDE,pLook,szLook,nLook);
          if( rc!=SQLITE_OK ) abendError("lookaside configuration filed: %d", rc);
        }
    #ifndef SQLITE_OMIT_TRACE
        sqlite3_trace(db, verboseFlag ? traceCallback : traceNoop, 0);
    #endif
        sqlite3_create_function(db, "eval", 1, SQLITE_UTF8, 0, sqlEvalFunc, 0, 0);
        sqlite3_create_function(db, "eval", 2, SQLITE_UTF8, 0, sqlEvalFunc, 0, 0);
        sqlite3_create_module(db, "generate_series", &seriesModule, 0);
        sqlite3_limit(db, SQLITE_LIMIT_LENGTH, 1000000);
        if( zEncoding ) sqlexec(db, "PRAGMA encoding=%s", zEncoding);
        if( pageSize ) sqlexec(db, "PRAGMA pagesize=%d", pageSize);
        if( doAutovac ) sqlexec(db, "PRAGMA auto_vacuum=FULL");
        iStart = timeOfDay();
        g.bOomEnable = 1;
        if( verboseFlag ){
          zErrMsg = 0;
          rc = sqlite3_exec(db, zSql, execCallback, 0, &zErrMsg);
          if( zErrMsg ){
            sqlite3_snprintf(sizeof(zErrBuf),zErrBuf,"%z", zErrMsg);
            zErrMsg = 0;
          }
        }else {
          rc = sqlite3_exec(db, zSql, execNoop, 0, 0);
        }
        g.bOomEnable = 0;
        iEnd = timeOfDay();
        rc = sqlite3_close(db);
        if( rc ){
          abendError("sqlite3_close() failed with rc=%d", rc);
        }
        if( !zDataOut && sqlite3_memory_used()>0 ){
          abendError("memory in use after close: %lld bytes",sqlite3_memory_used());
        }
        if( oomFlag ){
          /* Limit the number of iterations of the OOM loop to OOM_MAX.  If the
          ** first pass (single failure) exceeds 2/3rds of OOM_MAX this skip the
          ** second pass (continuous failure after first) completely. */
          if( g.nOomFault==0 || oomCnt>OOM_MAX ){
            if( g.bOomOnce && oomCnt<=(OOM_MAX*2/3) ){
              oomCnt = g.iOomCntdown = 1;
              g.bOomOnce = 0;
            }else{
              oomCnt = 0;
            }
          }else{
            g.iOomCntdown = ++oomCnt;
            g.nOomFault = 0;
          }
          if( oomCnt ){
            if( verboseFlag ){
              printf("%s.%d\n", g.bOomOnce ? "Once" : "Multi", oomCnt);
              fflush(stdout);
            }
            nTest++;
          }
        }
      }while( oomCnt>0 );

      /* Store unique test cases in the in the dataDb database if the
      ** --unique-cases flag is present
      */
      if( zDataOut ){
        sqlite3_bind_blob(pStmt, 1, &zIn[i], iNext-i, SQLITE_STATIC);
        sqlite3_bind_int64(pStmt, 2, iEnd - iStart);
        rc = sqlite3_step(pStmt);
        if( rc!=SQLITE_DONE ) abendError("%s", sqlite3_errmsg(dataDb));
        sqlite3_reset(pStmt);
      }

      /* Free the SQL from the current test case
      */
      if( zToFree ){
        sqlite3_free(zToFree);
        zToFree = 0;
      }
      zIn[iNext] = cSaved;

      /* Show test-case results in --verbose mode
      */
      if( verboseFlag ){
        printf("RESULT-CODE: %d\n", rc);
        if( zErrMsg ){
          printf("ERROR-MSG: [%s]\n", zErrBuf);
        }
        fflush(stdout);
      }

      /* Simulate an error if the TEST_FAILURE environment variable is "5".
      ** This is used to verify that automated test script really do spot
      ** errors that occur in this test program.
      */
      if( zFailCode ){
        if( zFailCode[0]=='5' && zFailCode[1]==0 ){
          abendError("simulated failure");
        }else if( zFailCode[0]!=0 ){
          /* If TEST_FAILURE is something other than 5, just exit the test
          ** early */
          printf("\nExit early due to TEST_FAILURE being set");
          break;
        }
      }
    }
    if( !verboseFlag && multiTest && !quietFlag && !oomFlag ) printf("\n");
  }

  /* Report total number of tests run
  */
  if( nTest>1 && !quietFlag ){
    sqlite3_int64 iElapse = timeOfDay() - iBegin;
    printf("%s: 0 errors out of %d tests in %d.%03d seconds\nSQLite %s %s\n",
           g.zArgv0, nTest, (int)(iElapse/1000), (int)(iElapse%1000),
           sqlite3_libversion(), sqlite3_sourceid());
  }

  /* Write the unique test cases if the --unique-cases flag was used
  */
  if( zDataOut ){
    int n = 0;
    FILE *out = fopen(zDataOut, "wb");
    if( out==0 ) abendError("cannot open %s for writing", zDataOut);
    if( nHeader>0 ) fwrite(zIn, nHeader, 1, out);
    sqlite3_finalize(pStmt);
    rc = sqlite3_prepare_v2(dataDb, "SELECT sql, tm FROM testcase ORDER BY tm, sql",
                            -1, &pStmt, 0);
    if( rc ) abendError("%s", sqlite3_errmsg(dataDb));
    while( sqlite3_step(pStmt)==SQLITE_ROW ){
      fprintf(out,"/****<%d:%dms>****/", ++n, sqlite3_column_int(pStmt,1));
      fwrite(sqlite3_column_blob(pStmt,0),sqlite3_column_bytes(pStmt,0),1,out);
    }
    fclose(out);
    sqlite3_finalize(pStmt);
    sqlite3_close(dataDb);
  }

  /* Clean up and exit.
  */
  free(azInFile);
  free(zIn);
  free(pHeap);
  free(pLook);
  free(pScratch);
  free(pPCache);
  return 0;
}
