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mirror of https://github.com/sqlite/sqlite.git synced 2025-07-27 20:41:58 +03:00

Build the generate_series(START,END,STEP) table-valued function into

fuzzershell, to make it easier to construct compact test cases that contain
actual data.

FossilOrigin-Name: 672c21bcf09c5bfb67e061456a56be45409c4f34
This commit is contained in:
drh
2016-09-03 16:23:42 +00:00
parent c6952addf7
commit 9f6dd025ba
3 changed files with 329 additions and 8 deletions

View File

@ -312,6 +312,326 @@ static void sqlEvalFunc(
/* 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
*/
@ -729,6 +1049,7 @@ int main(int argc, char **argv){
#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);