/*

** 2008 March 19

**

** 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.

**

*************************************************************************

** Code for testing all sorts of SQLite interfaces.  This code

** implements new SQL functions used by the test scripts.

**

** $Id: test_func.c,v 1.13 2008/08/28 02:26:07 drh Exp $

*/

#include "sqlite3.h"

#include "tcl.h"

#include <stdlib.h>

#include <string.h>

#include <assert.h>

/*

** Allocate nByte bytes of space using sqlite3_malloc(). If the

** allocation fails, call sqlite3_result_error_nomem() to notify

** the database handle that malloc() has failed.

*/

static void *testContextMalloc(sqlite3_context *context, int nByte){

  char *z = sqlite3_malloc(nByte);

  if( !z && nByte>0 ){

    sqlite3_result_error_nomem(context);

  }

  return z;

}

/*

** This function generates a string of random characters.  Used for

** generating test data.

*/

static void randStr(sqlite3_context *context, int argc, sqlite3_value **argv){

  static const unsigned char zSrc[] = 

     "abcdefghijklmnopqrstuvwxyz"

     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

     "0123456789"

     ".-!,:*^+=_|?/<> ";

  int iMin, iMax, n, r, i;

  unsigned char zBuf[1000];

  /* It used to be possible to call randstr() with any number of arguments,

  ** but now it is registered with SQLite as requiring exactly 2.

  */

  assert(argc==2);

  iMin = sqlite3_value_int(argv[0]);

  if( iMin<0 ) iMin = 0;

  if( iMin>=sizeof(zBuf) ) iMin = sizeof(zBuf)-1;

  iMax = sqlite3_value_int(argv[1]);

  if( iMax<iMin ) iMax = iMin;

  if( iMax>=sizeof(zBuf) ) iMax = sizeof(zBuf)-1;

  n = iMin;

  if( iMax>iMin ){

    sqlite3_randomness(sizeof(r), &r);

    r &= 0x7fffffff;

    n += r%(iMax + 1 - iMin);

  }

  assert( n<sizeof(zBuf) );

  sqlite3_randomness(n, zBuf);

  for(i=0; i<n; i++){

    zBuf[i] = zSrc[zBuf[i]%(sizeof(zSrc)-1)];

  }

  zBuf[n] = 0;

  sqlite3_result_text(context, (char*)zBuf, n, SQLITE_TRANSIENT);

}

/*

** The following two SQL functions are used to test returning a text

** result with a destructor. Function 'test_destructor' takes one argument

** and returns the same argument interpreted as TEXT. A destructor is

** passed with the sqlite3_result_text() call.

**

** SQL function 'test_destructor_count' returns the number of outstanding 

** allocations made by 'test_destructor';

**

** WARNING: Not threadsafe.

*/

static int test_destructor_count_var = 0;

static void destructor(void *p){

  char *zVal = (char *)p;

  assert(zVal);

  zVal--;

  sqlite3_free(zVal);

  test_destructor_count_var--;

}

static void test_destructor(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  char *zVal;

  int len;

  test_destructor_count_var++;

  assert( nArg==1 );

  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;

  len = sqlite3_value_bytes(argv[0]); 

  zVal = testContextMalloc(pCtx, len+3);

  if( !zVal ){

    return;

  }

  zVal[len+1] = 0;

  zVal[len+2] = 0;

  zVal++;

  memcpy(zVal, sqlite3_value_text(argv[0]), len);

  sqlite3_result_text(pCtx, zVal, -1, destructor);

}

#ifndef SQLITE_OMIT_UTF16

static void test_destructor16(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  char *zVal;

  int len;

  test_destructor_count_var++;

  assert( nArg==1 );

  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;

  len = sqlite3_value_bytes16(argv[0]); 

  zVal = testContextMalloc(pCtx, len+3);

  if( !zVal ){

    return;

  }

  zVal[len+1] = 0;

  zVal[len+2] = 0;

  zVal++;

  memcpy(zVal, sqlite3_value_text16(argv[0]), len);

  sqlite3_result_text16(pCtx, zVal, -1, destructor);

}

#endif

static void test_destructor_count(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  sqlite3_result_int(pCtx, test_destructor_count_var);

}

/*

** Routines for testing the sqlite3_get_auxdata() and sqlite3_set_auxdata()

** interface.

**

** The test_auxdata() SQL function attempts to register each of its arguments

** as auxiliary data.  If there are no prior registrations of aux data for

** that argument (meaning the argument is not a constant or this is its first

** call) then the result for that argument is 0.  If there is a prior

** registration, the result for that argument is 1.  The overall result

** is the individual argument results separated by spaces.

*/

static void free_test_auxdata(void *p) {sqlite3_free(p);}

static void test_auxdata(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  int i;

  char *zRet = testContextMalloc(pCtx, nArg*2);

  if( !zRet ) return;

  memset(zRet, 0, nArg*2);

  for(i=0; i<nArg; i++){

    char const *z = (char*)sqlite3_value_text(argv[i]);

    if( z ){

      int n;

      char *zAux = sqlite3_get_auxdata(pCtx, i);

      if( zAux ){

        zRet[i*2] = '1';

        assert( strcmp(zAux,z)==0 );

      }else {

        zRet[i*2] = '0';

      }

      n = strlen(z) + 1;

      zAux = testContextMalloc(pCtx, n);

      if( zAux ){

        memcpy(zAux, z, n);

        sqlite3_set_auxdata(pCtx, i, zAux, free_test_auxdata);

      }

      zRet[i*2+1] = ' ';

    }

  }

  sqlite3_result_text(pCtx, zRet, 2*nArg-1, free_test_auxdata);

}

/*

** A function to test error reporting from user functions. This function

** returns a copy of its first argument as the error message.  If the

** second argument exists, it becomes the error code.

*/

static void test_error(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  sqlite3_result_error(pCtx, (char*)sqlite3_value_text(argv[0]), -1);

  if( nArg==2 ){

    sqlite3_result_error_code(pCtx, sqlite3_value_int(argv[1]));

  }

}

/*

** Implementation of the counter(X) function.  If X is an integer

** constant, then the first invocation will return X.  The second X+1.

** and so forth.  Can be used (for example) to provide a sequence number

** in a result set.

*/

static void counterFunc(

  sqlite3_context *pCtx,   /* Function context */

  int nArg,                /* Number of function arguments */

  sqlite3_value **argv     /* Values for all function arguments */

){

  int *pCounter = (int*)sqlite3_get_auxdata(pCtx, 0);

  if( pCounter==0 ){

    pCounter = sqlite3_malloc( sizeof(*pCounter) );

    if( pCounter==0 ){

      sqlite3_result_error_nomem(pCtx);

      return;

    }

    *pCounter = sqlite3_value_int(argv[0]);

    sqlite3_set_auxdata(pCtx, 0, pCounter, sqlite3_free);

  }else{

    ++*pCounter;

  }

  sqlite3_result_int(pCtx, *pCounter);

}

/*

** This function takes two arguments.  It performance UTF-8/16 type

** conversions on the first argument then returns a copy of the second

** argument.

**

** This function is used in cases such as the following:

**

**      SELECT test_isolation(x,x) FROM t1;

**

** We want to verify that the type conversions that occur on the

** first argument do not invalidate the second argument.

*/

static void test_isolation(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

#ifndef SQLITE_OMIT_UTF16

  sqlite3_value_text16(argv[0]);

  sqlite3_value_text(argv[0]);

  sqlite3_value_text16(argv[0]);

  sqlite3_value_text(argv[0]);

#endif

  sqlite3_result_value(pCtx, argv[1]);

}

/*

** Invoke an SQL statement recursively.  The function result is the 

** first column of the first row of the result set.

*/

static void test_eval(

  sqlite3_context *pCtx, 

  int nArg,

  sqlite3_value **argv

){

  sqlite3_stmt *pStmt;

  int rc;

  sqlite3 *db = sqlite3_context_db_handle(pCtx);

  const char *zSql;

  zSql = (char*)sqlite3_value_text(argv[0]);

  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);

  if( rc==SQLITE_OK ){

    rc = sqlite3_step(pStmt);

    if( rc==SQLITE_ROW ){

      sqlite3_result_value(pCtx, sqlite3_column_value(pStmt, 0));

    }

    rc = sqlite3_finalize(pStmt);

  }

  if( rc ){

    char *zErr;

    assert( pStmt==0 );

    zErr = sqlite3_mprintf("sqlite3_prepare_v2() error: %s",sqlite3_errmsg(db));

    sqlite3_result_text(pCtx, zErr, -1, sqlite3_free);

    sqlite3_result_error_code(pCtx, rc);

  }

}

static int registerTestFunctions(sqlite3 *db){

  static const struct {

     char *zName;

     signed char nArg;

     unsigned char eTextRep; /* 1: UTF-16.  0: UTF-8 */

     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);

  } aFuncs[] = {

    { "randstr",               2, SQLITE_UTF8, randStr    },

    { "test_destructor",       1, SQLITE_UTF8, test_destructor},

#ifndef SQLITE_OMIT_UTF16

    { "test_destructor16",     1, SQLITE_UTF8, test_destructor16},

#endif

    { "test_destructor_count", 0, SQLITE_UTF8, test_destructor_count},

    { "test_auxdata",         -1, SQLITE_UTF8, test_auxdata},

    { "test_error",            1, SQLITE_UTF8, test_error},

    { "test_error",            2, SQLITE_UTF8, test_error},

    { "test_eval",             1, SQLITE_UTF8, test_eval},

    { "test_isolation",        2, SQLITE_UTF8, test_isolation},

    { "test_counter",          1, SQLITE_UTF8, counterFunc},

  };

  int i;

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

    sqlite3_create_function(db, aFuncs[i].zName, aFuncs[i].nArg,

        aFuncs[i].eTextRep, 0, aFuncs[i].xFunc, 0, 0);

  }

  return SQLITE_OK;

}

/*

** TCLCMD:  autoinstall_test_functions

**

** Invoke this TCL command to use sqlite3_auto_extension() to cause

** the standard set of test functions to be loaded into each new

** database connection.

*/

static int autoinstall_test_funcs(

  void * clientData,

  Tcl_Interp *interp,

  int objc,

  Tcl_Obj *CONST objv[]

){

  extern int Md5_Register(sqlite3*);

  int rc = sqlite3_auto_extension((void*)registerTestFunctions);

  if( rc==SQLITE_OK ){

    rc = sqlite3_auto_extension((void*)Md5_Register);

  }

  Tcl_SetObjResult(interp, Tcl_NewIntObj(rc));

  return TCL_OK;

}

/*

** A bogus step function and finalizer function.

*/

static void tStep(sqlite3_context *a, int b, sqlite3_value **c){}

static void tFinal(sqlite3_context *a){}

/*

** tclcmd:  abuse_create_function

**

** Make various calls to sqlite3_create_function that do not have valid

** parameters.  Verify that the error condition is detected and reported.

*/

static int abuse_create_function(

  void * clientData,

  Tcl_Interp *interp,

  int objc,

  Tcl_Obj *CONST objv[]

){

  extern int getDbPointer(Tcl_Interp*, const char*, sqlite3**);

  sqlite3 *db;

  int rc;

  int mxArg;

  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;

  rc = sqlite3_create_function(db, "tx", 1, SQLITE_UTF8, 0, tStep,tStep,tFinal);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", 1, SQLITE_UTF8, 0, tStep, tStep, 0);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", 1, SQLITE_UTF8, 0, tStep, 0, tFinal);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", 1, SQLITE_UTF8, 0, 0, 0, tFinal);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", 1, SQLITE_UTF8, 0, 0, tStep, 0);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", -2, SQLITE_UTF8, 0, tStep, 0, 0);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "tx", 128, SQLITE_UTF8, 0, tStep, 0, 0);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  rc = sqlite3_create_function(db, "funcxx"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789",

       1, SQLITE_UTF8, 0, tStep, 0, 0);

  if( rc!=SQLITE_ERROR ) goto abuse_err;

  if( sqlite3_errcode(db)!=SQLITE_ERROR ) goto abuse_err;

  if( strcmp(sqlite3_errmsg(db), "bad parameters")!=0 ) goto abuse_err;

  /* This last function registration should actually work.  Generate

  ** a no-op function (that always returns NULL) and which has the

  ** maximum-length function name and the maximum number of parameters.

  */

  sqlite3_limit(db, SQLITE_LIMIT_FUNCTION_ARG, 10000);

  mxArg = sqlite3_limit(db, SQLITE_LIMIT_FUNCTION_ARG, -1);

  rc = sqlite3_create_function(db, "nullx"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789"

       "_123456789_123456789_123456789_123456789_123456789",

       mxArg, SQLITE_UTF8, 0, tStep, 0, 0);

  if( rc!=SQLITE_OK ) goto abuse_err;

  return TCL_OK;

abuse_err:

  Tcl_AppendResult(interp, "sqlite3_create_function abused test failed", 

                   (char*)0);

  return TCL_ERROR;

}

/*

** Register commands with the TCL interpreter.

*/

int Sqlitetest_func_Init(Tcl_Interp *interp){

  static struct {

     char *zName;

     Tcl_ObjCmdProc *xProc;

  } aObjCmd[] = {

     { "autoinstall_test_functions",    autoinstall_test_funcs },

     { "abuse_create_function",         abuse_create_function  },

  };

  int i;

  extern int Md5_Register(sqlite3*);

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

    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);

  }

  sqlite3_initialize();

  sqlite3_auto_extension((void*)registerTestFunctions);

  sqlite3_auto_extension((void*)Md5_Register);

  return TCL_OK;

}