/*

 ** 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;

 }