Adding upstream version 3.40.1.upstream/3.40.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 461 insertions, 0 deletions

diff --git a/ext/misc/qpvtab.c b/ext/misc/qpvtab.c
new file mode 100644
index 0000000..fb0c155
--- /dev/null
+++ b/ext/misc/qpvtab.c
@@ -0,0 +1,461 @@
+/*
+** 2022-01-19
+**
+** 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.
+**
+*************************************************************************
+**
+** This file implements a virtual-table that returns information about
+** how the query planner called the xBestIndex method.  This virtual table
+** is intended for testing and debugging only.
+**
+** The schema of the virtual table is this:
+**
+**    CREATE TABLE qpvtab(
+**      vn     TEXT,           -- Name of an sqlite3_index_info field
+**      ix     INTEGER,        -- Array index or value
+**      cn     TEXT,           -- Column name
+**      op     INTEGER,        -- operator
+**      ux     BOOLEAN,        -- "usable" field
+**      rhs    TEXT,           -- sqlite3_vtab_rhs_value()
+**
+**      a, b, c, d, e,         -- Extra columns to attach constraints to
+**
+**      flags    INTEGER HIDDEN  -- control flags
+**    );
+**
+** The virtual table returns a description of the sqlite3_index_info object
+** that was provided to the (successful) xBestIndex method.  There is one
+** row in the result table for each field in the sqlite3_index_info object.
+**
+** The values of the "a" through "e" columns are one of:
+**
+**    1.   TEXT - the same as the column name
+**    2.   INTEGER - 1 for "a", 2 for "b", and so forth
+**
+** Option 1 is the default behavior.  2 is use if there is a usable
+** constraint on "flags" with an integer right-hand side that where the
+** value of the right-hand side has its 0x001 bit set.
+**
+** All constraints on columns "a" through "e" are marked as "omit".
+**
+** If there is a usable constraint on "flags" that has a RHS value that
+** is an integer and that integer has its 0x02 bit set, then the
+** orderByConsumed flag is set.
+**
+** FLAGS SUMMARY:
+**
+**   0x001               Columns 'a' through 'e' have INT values
+**   0x002               orderByConsumed is set
+**   0x004               OFFSET and LIMIT have omit set
+**
+** COMPILE:
+**
+**   gcc -Wall -g -shared -fPIC -I. qpvtab.c -o qqvtab.so
+**
+** EXAMPLE USAGE:
+**
+**   .load ./qpvtab
+**   SELECT rowid, *, flags FROM qpvtab(102)
+**    WHERE a=19
+**      AND b BETWEEN 4.5 and 'hello'
+**      AND c<>x'aabbcc'
+**    ORDER BY d, e DESC;
+*/
+#if !defined(SQLITEINT_H)
+#include "sqlite3ext.h"
+#endif
+SQLITE_EXTENSION_INIT1
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+
+#if !defined(SQLITE_OMIT_VIRTUALTABLE)
+
+/* qpvtab_vtab is a subclass of sqlite3_vtab which is
+** underlying representation of the virtual table
+*/
+typedef struct qpvtab_vtab qpvtab_vtab;
+struct qpvtab_vtab {
+  sqlite3_vtab base;  /* Base class - must be first */
+};
+
+/* qpvtab_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 qpvtab_cursor qpvtab_cursor;
+struct qpvtab_cursor {
+  sqlite3_vtab_cursor base;  /* Base class - must be first */
+  sqlite3_int64 iRowid;      /* The rowid */
+  const char *zData;         /* Data to return */
+  int nData;                 /* Number of bytes of data */
+  int flags;                 /* Flags value */
+};
+
+/*
+** Names of columns
+*/
+static const char *azColname[] = {
+  "vn",
+  "ix",
+  "cn",
+  "op",
+  "ux",
+  "rhs",
+  "a", "b", "c", "d", "e",
+  "flags",
+  ""
+};
+
+/*
+** The qpvtabConnect() method is invoked to create a new
+** qpvtab virtual table.
+*/
+static int qpvtabConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  qpvtab_vtab *pNew;
+  int rc;
+
+  rc = sqlite3_declare_vtab(db,
+         "CREATE TABLE x("
+         " vn TEXT,"
+         " ix INT,"
+         " cn TEXT,"
+         " op INT,"
+         " ux BOOLEAN,"
+         " rhs TEXT,"
+         " a, b, c, d, e,"
+         " flags INT HIDDEN)"
+       );
+#define QPVTAB_VN      0
+#define QPVTAB_IX      1
+#define QPVTAB_CN      2
+#define QPVTAB_OP      3
+#define QPVTAB_UX      4
+#define QPVTAB_RHS     5
+#define QPVTAB_A       6
+#define QPVTAB_B       7
+#define QPVTAB_C       8
+#define QPVTAB_D       9
+#define QPVTAB_E      10
+#define QPVTAB_FLAGS  11
+#define QPVTAB_NONE   12
+  if( rc==SQLITE_OK ){
+    pNew = sqlite3_malloc( sizeof(*pNew) );
+    *ppVtab = (sqlite3_vtab*)pNew;
+    if( pNew==0 ) return SQLITE_NOMEM;
+    memset(pNew, 0, sizeof(*pNew));
+  }
+  return rc;
+}
+
+/*
+** This method is the destructor for qpvtab_vtab objects.
+*/
+static int qpvtabDisconnect(sqlite3_vtab *pVtab){
+  qpvtab_vtab *p = (qpvtab_vtab*)pVtab;
+  sqlite3_free(p);
+  return SQLITE_OK;
+}
+
+/*
+** Constructor for a new qpvtab_cursor object.
+*/
+static int qpvtabOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
+  qpvtab_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 qpvtab_cursor.
+*/
+static int qpvtabClose(sqlite3_vtab_cursor *cur){
+  qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
+  sqlite3_free(pCur);
+  return SQLITE_OK;
+}
+
+
+/*
+** Advance a qpvtab_cursor to its next row of output.
+*/
+static int qpvtabNext(sqlite3_vtab_cursor *cur){
+  qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
+  if( pCur->iRowid<pCur->nData ){
+    const char *z = &pCur->zData[pCur->iRowid];
+    const char *zEnd = strchr(z, '\n');
+    if( zEnd ) zEnd++;
+    pCur->iRowid = (int)(zEnd - pCur->zData);
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Return values of columns for the row at which the qpvtab_cursor
+** is currently pointing.
+*/
+static int qpvtabColumn(
+  sqlite3_vtab_cursor *cur,   /* The cursor */
+  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
+  int i                       /* Which column to return */
+){
+  qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
+  if( i>=QPVTAB_VN && i<=QPVTAB_RHS && pCur->iRowid<pCur->nData ){
+    const char *z = &pCur->zData[pCur->iRowid];
+    const char *zEnd;
+    int j;
+    j = QPVTAB_VN;
+    while(1){
+      zEnd = strchr(z, j==QPVTAB_RHS ? '\n' : ',');
+      if( j==i || zEnd==0 ) break;
+      z = zEnd+1;
+      j++;
+    }
+    if( zEnd==z ){
+      sqlite3_result_null(ctx);
+    }else if( i==QPVTAB_IX || i==QPVTAB_OP || i==QPVTAB_UX ){
+      sqlite3_result_int(ctx, atoi(z));
+    }else{
+      sqlite3_result_text64(ctx, z, zEnd-z, SQLITE_TRANSIENT, SQLITE_UTF8);
+    }
+  }else if( i>=QPVTAB_A && i<=QPVTAB_E ){
+    if( pCur->flags & 0x001 ){
+      sqlite3_result_int(ctx, i-QPVTAB_A+1);
+    }else{
+      char x = 'a'+i-QPVTAB_A;
+      sqlite3_result_text64(ctx, &x, 1, SQLITE_TRANSIENT, SQLITE_UTF8);
+    }
+  }else if( i==QPVTAB_FLAGS ){
+    sqlite3_result_int(ctx, pCur->flags);
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Return the rowid for the current row.  In this implementation, the
+** rowid is the same as the output value.
+*/
+static int qpvtabRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  qpvtab_cursor *pCur = (qpvtab_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 qpvtabEof(sqlite3_vtab_cursor *cur){
+  qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
+  return pCur->iRowid>=pCur->nData;
+}
+
+/*
+** This method is called to "rewind" the qpvtab_cursor object back
+** to the first row of output.  This method is always called at least
+** once prior to any call to qpvtabColumn() or qpvtabRowid() or 
+** qpvtabEof().
+*/
+static int qpvtabFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  qpvtab_cursor *pCur = (qpvtab_cursor *)pVtabCursor;
+  pCur->iRowid = 0;
+  pCur->zData = idxStr;
+  pCur->nData = (int)strlen(idxStr);
+  pCur->flags = idxNum;
+  return SQLITE_OK;
+}
+
+/*
+** Append the text of a value to pStr
+*/
+static void qpvtabStrAppendValue(
+  sqlite3_str *pStr,
+  sqlite3_value *pVal
+){
+  switch( sqlite3_value_type(pVal) ){
+    case SQLITE_NULL:
+      sqlite3_str_appendf(pStr, "NULL");
+      break;
+    case SQLITE_INTEGER:
+      sqlite3_str_appendf(pStr, "%lld", sqlite3_value_int64(pVal));
+      break;
+    case SQLITE_FLOAT:
+      sqlite3_str_appendf(pStr, "%!f", sqlite3_value_double(pVal));
+      break;
+    case SQLITE_TEXT: {
+      int i;
+      const char *a = (const char*)sqlite3_value_text(pVal);
+      int n = sqlite3_value_bytes(pVal);
+      sqlite3_str_append(pStr, "'", 1);
+      for(i=0; i<n; i++){
+        char c = a[i];
+        if( c=='\n' ) c = ' ';
+        sqlite3_str_append(pStr, &c, 1);
+        if( c=='\'' ) sqlite3_str_append(pStr, &c, 1);
+      }
+      sqlite3_str_append(pStr, "'", 1);
+      break;
+    }
+    case SQLITE_BLOB: {
+      int i;
+      const unsigned char *a = sqlite3_value_blob(pVal);
+      int n = sqlite3_value_bytes(pVal);
+      sqlite3_str_append(pStr, "x'", 2);
+      for(i=0; i<n; i++){
+        sqlite3_str_appendf(pStr, "%02x", a[i]);
+      }
+      sqlite3_str_append(pStr, "'", 1);
+      break;
+    }
+  }
+}
+
+/*
+** SQLite will invoke this method one or more times while planning a query
+** that uses the virtual table.  This routine needs to create
+** a query plan for each invocation and compute an estimated cost for that
+** plan.
+*/
+static int qpvtabBestIndex(
+  sqlite3_vtab *tab,
+  sqlite3_index_info *pIdxInfo
+){
+  sqlite3_str *pStr = sqlite3_str_new(0);
+  int i, k = 0;
+  int rc;
+  sqlite3_str_appendf(pStr, "nConstraint,%d,,,,\n", pIdxInfo->nConstraint);
+  for(i=0; i<pIdxInfo->nConstraint; i++){
+    sqlite3_value *pVal;
+    int iCol = pIdxInfo->aConstraint[i].iColumn;
+    int op = pIdxInfo->aConstraint[i].op;
+    if( iCol==QPVTAB_FLAGS &&  pIdxInfo->aConstraint[i].usable ){
+      pVal = 0;
+      rc = sqlite3_vtab_rhs_value(pIdxInfo, i, &pVal);
+      assert( rc==SQLITE_OK || pVal==0 );
+      if( pVal ){
+        pIdxInfo->idxNum = sqlite3_value_int(pVal);
+        if( pIdxInfo->idxNum & 0x002 ) pIdxInfo->orderByConsumed = 1;
+      }
+    }
+    if( op==SQLITE_INDEX_CONSTRAINT_LIMIT
+     || op==SQLITE_INDEX_CONSTRAINT_OFFSET
+    ){
+      iCol = QPVTAB_NONE;
+    }
+    sqlite3_str_appendf(pStr,"aConstraint,%d,%s,%d,%d,",
+       i,
+       azColname[iCol],
+       op,
+       pIdxInfo->aConstraint[i].usable);
+    pVal = 0;
+    rc = sqlite3_vtab_rhs_value(pIdxInfo, i, &pVal);
+    assert( rc==SQLITE_OK || pVal==0 );
+    if( pVal ){
+      qpvtabStrAppendValue(pStr, pVal);
+    }
+    sqlite3_str_append(pStr, "\n", 1);
+  }
+  for(i=0; i<pIdxInfo->nConstraint; i++){
+    int iCol = pIdxInfo->aConstraint[i].iColumn;
+    int op = pIdxInfo->aConstraint[i].op;
+    if( op==SQLITE_INDEX_CONSTRAINT_LIMIT
+     || op==SQLITE_INDEX_CONSTRAINT_OFFSET
+    ){
+      iCol = QPVTAB_NONE;
+    }
+    if( iCol>=QPVTAB_A && pIdxInfo->aConstraint[i].usable ){
+      pIdxInfo->aConstraintUsage[i].argvIndex = ++k;
+      if( iCol<=QPVTAB_FLAGS || (pIdxInfo->idxNum & 0x004)!=0 ){
+        pIdxInfo->aConstraintUsage[i].omit = 1;
+      }
+    }
+  }
+  sqlite3_str_appendf(pStr, "nOrderBy,%d,,,,\n", pIdxInfo->nOrderBy);
+  for(i=0; i<pIdxInfo->nOrderBy; i++){
+    int iCol = pIdxInfo->aOrderBy[i].iColumn;
+    sqlite3_str_appendf(pStr, "aOrderBy,%d,%s,%d,,\n",i,
+      iCol>=0 ? azColname[iCol] : "rowid",
+      pIdxInfo->aOrderBy[i].desc
+    );
+  }
+  sqlite3_str_appendf(pStr, "sqlite3_vtab_distinct,%d,,,,\n", 
+                      sqlite3_vtab_distinct(pIdxInfo));
+  sqlite3_str_appendf(pStr, "idxFlags,%d,,,,\n", pIdxInfo->idxFlags);
+  sqlite3_str_appendf(pStr, "colUsed,%d,,,,\n", (int)pIdxInfo->colUsed);
+  pIdxInfo->estimatedCost = (double)10;
+  pIdxInfo->estimatedRows = 10;
+  sqlite3_str_appendf(pStr, "idxNum,%d,,,,\n", pIdxInfo->idxNum);
+  sqlite3_str_appendf(pStr, "orderByConsumed,%d,,,,\n",
+                      pIdxInfo->orderByConsumed);
+  pIdxInfo->idxStr = sqlite3_str_finish(pStr);
+  pIdxInfo->needToFreeIdxStr = 1;
+  return SQLITE_OK;
+}
+
+/*
+** This following structure defines all the methods for the 
+** virtual table.
+*/
+static sqlite3_module qpvtabModule = {
+  /* iVersion    */ 0,
+  /* xCreate     */ 0,
+  /* xConnect    */ qpvtabConnect,
+  /* xBestIndex  */ qpvtabBestIndex,
+  /* xDisconnect */ qpvtabDisconnect,
+  /* xDestroy    */ 0,
+  /* xOpen       */ qpvtabOpen,
+  /* xClose      */ qpvtabClose,
+  /* xFilter     */ qpvtabFilter,
+  /* xNext       */ qpvtabNext,
+  /* xEof        */ qpvtabEof,
+  /* xColumn     */ qpvtabColumn,
+  /* xRowid      */ qpvtabRowid,
+  /* xUpdate     */ 0,
+  /* xBegin      */ 0,
+  /* xSync       */ 0,
+  /* xCommit     */ 0,
+  /* xRollback   */ 0,
+  /* xFindMethod */ 0,
+  /* xRename     */ 0,
+  /* xSavepoint  */ 0,
+  /* xRelease    */ 0,
+  /* xRollbackTo */ 0,
+  /* xShadowName */ 0
+};
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int sqlite3_qpvtab_init(
+  sqlite3 *db, 
+  char **pzErrMsg, 
+  const sqlite3_api_routines *pApi
+){
+  int rc = SQLITE_OK;
+  SQLITE_EXTENSION_INIT2(pApi);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  rc = sqlite3_create_module(db, "qpvtab", &qpvtabModule, 0);
+#endif
+  return rc;
+}