SQLite

Check-in [988a61e8b0]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Code to automatically create eponymous virtual tables for read-only pragmas. Compiles, but does not yet work.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | pragma-as-vtab
Files: files | file ages | folders
SHA1: 988a61e8b03f302c69d11898d1ea95f002cba1a5
User & Date: drh 2016-12-15 20:59:03.895
Context
2016-12-15
21:11
The pragma as eponymous virtual table mechanism now appears to work. (check-in: 2c274a1a7b user: drh tags: pragma-as-vtab)
20:59
Code to automatically create eponymous virtual tables for read-only pragmas. Compiles, but does not yet work. (check-in: 988a61e8b0 user: drh tags: pragma-as-vtab)
16:01
Do more pragma processing from tables rather than in-line code. (Closed-Leaf check-in: a88ca3524b user: drh tags: table-driven-pragma)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/build.c.
348
349
350
351
352
353
354



355
356
357
358
359
360
361
    const char *zMsg = flags & LOCATE_VIEW ? "no such view" : "no such table";
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( sqlite3FindDbName(pParse->db, zDbase)<1 ){
      /* If zName is the not the name of a table in the schema created using
      ** CREATE, then check to see if it is the name of an virtual table that
      ** can be an eponymous virtual table. */
      Module *pMod = (Module*)sqlite3HashFind(&pParse->db->aModule, zName);



      if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
        return pMod->pEpoTab;
      }
    }
#endif
    if( (flags & LOCATE_NOERR)==0 ){
      if( zDbase ){







>
>
>







348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
    const char *zMsg = flags & LOCATE_VIEW ? "no such view" : "no such table";
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( sqlite3FindDbName(pParse->db, zDbase)<1 ){
      /* If zName is the not the name of a table in the schema created using
      ** CREATE, then check to see if it is the name of an virtual table that
      ** can be an eponymous virtual table. */
      Module *pMod = (Module*)sqlite3HashFind(&pParse->db->aModule, zName);
      if( pMod==0 && sqlite3_strnicmp(zName, "pragma_", 7)==0 ){
        pMod = sqlite3PragmaVtabRegister(pParse->db, zName);
      }
      if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
        return pMod->pEpoTab;
      }
    }
#endif
    if( (flags & LOCATE_NOERR)==0 ){
      if( zDbase ){
Changes to src/pragma.c.
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
}
#endif /* SQLITE_PAGER_PRAGMAS */

/*
** Set result column names for a pragma.
*/
static void setPragmaResultColumnNames(
  Vdbe *v,                              /* The query under construction */
  const struct sPragmaNames *pPragma    /* The pragma */
){
  u8 n = pPragma->nPragCName;
  sqlite3VdbeSetNumCols(v, n==0 ? 1 : n);
  if( n==0 ){
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, pPragma->zName, SQLITE_STATIC);
  }else{
    int i, j;







|
|







162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
}
#endif /* SQLITE_PAGER_PRAGMAS */

/*
** Set result column names for a pragma.
*/
static void setPragmaResultColumnNames(
  Vdbe *v,                     /* The query under construction */
  const PragmaName *pPragma    /* The pragma */
){
  u8 n = pPragma->nPragCName;
  sqlite3VdbeSetNumCols(v, n==0 ? 1 : n);
  if( n==0 ){
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, pPragma->zName, SQLITE_STATIC);
  }else{
    int i, j;
270
271
272
273
274
275
276




















277
278
279
280
281
282
283
  assert( PAGER_JOURNALMODE_MEMORY==4 );
  assert( PAGER_JOURNALMODE_WAL==5 );
  assert( eMode>=0 && eMode<=ArraySize(azModeName) );

  if( eMode==ArraySize(azModeName) ) return 0;
  return azModeName[eMode];
}





















/*
** Process a pragma statement.  
**
** Pragmas are of this form:
**
**      PRAGMA [schema.]id [= value]







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
  assert( PAGER_JOURNALMODE_MEMORY==4 );
  assert( PAGER_JOURNALMODE_WAL==5 );
  assert( eMode>=0 && eMode<=ArraySize(azModeName) );

  if( eMode==ArraySize(azModeName) ) return 0;
  return azModeName[eMode];
}

/*
** Locate a pragma in the aPragmaName[] array.
*/
static const PragmaName *pragmaLocate(const char *zName){
  int upr, lwr, mid, rc;
  lwr = 0;
  upr = ArraySize(aPragmaName)-1;
  while( lwr<=upr ){
    mid = (lwr+upr)/2;
    rc = sqlite3_stricmp(zName, aPragmaName[mid].zName);
    if( rc==0 ) break;
    if( rc<0 ){
      upr = mid - 1;
    }else{
      lwr = mid + 1;
    }
  }
  return lwr>upr ? 0 : &aPragmaName[mid];
}

/*
** Process a pragma statement.  
**
** Pragmas are of this form:
**
**      PRAGMA [schema.]id [= value]
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  char *aFcntl[4];       /* Argument to SQLITE_FCNTL_PRAGMA */
  int iDb;               /* Database index for <database> */
  int lwr, upr, mid = 0;       /* Binary search bounds */
  int rc;                      /* return value form SQLITE_FCNTL_PRAGMA */
  sqlite3 *db = pParse->db;    /* The database connection */
  Db *pDb;                     /* The specific database being pragmaed */
  Vdbe *v = sqlite3GetVdbe(pParse);  /* Prepared statement */
  const struct sPragmaNames *pPragma;

  if( v==0 ) return;
  sqlite3VdbeRunOnlyOnce(v);
  pParse->nMem = 2;

  /* Interpret the [schema.] part of the pragma statement. iDb is the
  ** index of the database this pragma is being applied to in db.aDb[]. */







<




|







319
320
321
322
323
324
325

326
327
328
329
330
331
332
333
334
335
336
337
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  char *aFcntl[4];       /* Argument to SQLITE_FCNTL_PRAGMA */
  int iDb;               /* Database index for <database> */

  int rc;                      /* return value form SQLITE_FCNTL_PRAGMA */
  sqlite3 *db = pParse->db;    /* The database connection */
  Db *pDb;                     /* The specific database being pragmaed */
  Vdbe *v = sqlite3GetVdbe(pParse);  /* Prepared statement */
  const PragmaName *pPragma;   /* The pragma */

  if( v==0 ) return;
  sqlite3VdbeRunOnlyOnce(v);
  pParse->nMem = 2;

  /* Interpret the [schema.] part of the pragma statement. iDb is the
  ** index of the database this pragma is being applied to in db.aDb[]. */
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
    }
    pParse->nErr++;
    pParse->rc = rc;
    goto pragma_out;
  }

  /* Locate the pragma in the lookup table */
  lwr = 0;
  upr = ArraySize(aPragmaNames)-1;
  while( lwr<=upr ){
    mid = (lwr+upr)/2;
    rc = sqlite3_stricmp(zLeft, aPragmaNames[mid].zName);
    if( rc==0 ) break;
    if( rc<0 ){
      upr = mid - 1;
    }else{
      lwr = mid + 1;
    }
  }
  if( lwr>upr ) goto pragma_out;
  pPragma = &aPragmaNames[mid];

  /* Make sure the database schema is loaded if the pragma requires that */
  if( (pPragma->mPragFlg & PragFlg_NeedSchema)!=0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
  }

  /* Register the result column names for pragmas that return results */







<
|
<
<
<
<
<
<
<
<
<
<
|
<







395
396
397
398
399
400
401

402










403

404
405
406
407
408
409
410
    }
    pParse->nErr++;
    pParse->rc = rc;
    goto pragma_out;
  }

  /* Locate the pragma in the lookup table */

  pPragma = pragmaLocate(zLeft);










  if( pPragma==0 ) goto pragma_out;


  /* Make sure the database schema is loaded if the pragma requires that */
  if( (pPragma->mPragFlg & PragFlg_NeedSchema)!=0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
  }

  /* Register the result column names for pragmas that return results */
1946
1947
1948
1949
1950
1951
1952




















1953





















































































































































































































































































1954

  } /* End of the PRAGMA switch */

pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}










































































































































































































































































































#endif /* SQLITE_OMIT_PRAGMA */







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258

  } /* End of the PRAGMA switch */

pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*****************************************************************************
** Implementation of an eponymous virtual table that runs a pragma.
**
*/
typedef struct PragmaVtab PragmaVtab;
typedef struct PragmaVtabCursor PragmaVtabCursor;
struct PragmaVtab {
  sqlite3_vtab base;        /* Base class.  Must be first */
  sqlite3 *db;              /* The database connection to which it belongs */
  const PragmaName *pName;  /* Name of the pragma */
  u8 nHidden;               /* Number of hidden columns */
  u8 iHidden;               /* Index of the first hidden column */
};
struct PragmaVtabCursor {
  sqlite3_vtab_cursor base; /* Base class.  Must be first */
  sqlite3_stmt *pPragma;    /* The pragma statement to run */
  sqlite_int64 iRowid;      /* Current rowid */
  char *azArg[2];           /* Value of the argument and schema */
};

/* 
** Pragma virtual table module xConnect method.
*/
static int pragmaVtabConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  const PragmaName *pPragma = (const PragmaName*)pAux;
  PragmaVtab *pTab = 0;
  int rc;
  int i, j;
  char cSep = '(';
  StrAccum acc;
  char zBuf[200];

  sqlite3StrAccumInit(&acc, 0, zBuf, sizeof(zBuf), 0);
  sqlite3StrAccumAppendAll(&acc, "CREATE TABLE x");
  for(i=0, j=pPragma->iPragCName; i<pPragma->nPragCName; i++, j++){
    sqlite3StrAccumAppend(&acc, &cSep, 1);
    sqlite3StrAccumAppendAll(&acc, pragCName[j]);
    cSep = ',';
  }
  j = 0;
  if( pPragma->mPragFlg & PragFlg_Result1 ){
    sqlite3StrAccumAppendAll(&acc, ",arg HIDDEN");
    j++;
  }
  if( pPragma->mPragFlg & (PragFlg_SchemaOpt|PragFlg_SchemaReq) ){
    sqlite3StrAccumAppendAll(&acc, ",schema HIDDEN");
    j++;
  }
  sqlite3StrAccumAppend(&acc, ")", 1);
  sqlite3StrAccumFinish(&acc);
  assert( strlen(zBuf) < sizeof(zBuf)-1 );
  rc = sqlite3_declare_vtab(db, zBuf);
  if( rc==SQLITE_OK ){
    pTab = (PragmaVtab*)sqlite3_malloc(sizeof(PragmaVtab));
    if( pTab==0 ){
      rc = SQLITE_NOMEM;
    }else{
      memset(pTab, 0, sizeof(PragmaVtab));
      pTab->pName = pPragma;
      pTab->db = db;
      pTab->iHidden = i;
      pTab->nHidden = j;
    }
  }else{
    *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
  }

  *ppVtab = (sqlite3_vtab*)pTab;
  return rc;
}

/* 
** Pragma virtual table module xDisconnect method.
*/
static int pragmaVtabDisconnect(sqlite3_vtab *pVtab){
  PragmaVtab *pTab = (PragmaVtab*)pVtab;
  sqlite3_free(pTab);
  return SQLITE_OK;
}

/* Figure out the best index to use to search a pragma virtual table.
**
** There are not really any index choices.  But we want to encourage the
** query planner to give == constraints on as many hidden parameters as
** possible, and especially on the first hidden parameter.  So return a
** high cost if hidden parameters are unconstrained.
*/
static int pragmaVtabBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  PragmaVtab *pTab = (PragmaVtab*)tab;
  const struct sqlite3_index_constraint *pConstraint;
  int i, j;
  int seen[2];

  if( pTab->nHidden==0 ){ return SQLITE_OK; }
  pConstraint = pIdxInfo->aConstraint;
  seen[0] = 0;
  seen[1] = 0;
  for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
    if( pConstraint->usable==0 ) continue;
    if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
    if( pConstraint->iColumn < pTab->iHidden ) continue;
    j = pConstraint->iColumn - pTab->iHidden;
    assert( j < 2 );
    if( seen[j] ) continue;
    seen[j] = i;
  }
  if( seen[0]==0 ){
    pIdxInfo->estimatedCost = (double)2147483647;
    pIdxInfo->estimatedRows = 2147483647;
    return SQLITE_OK;
  }
  j = seen[0];
  pIdxInfo->aConstraintUsage[j].argvIndex = 1;
  pIdxInfo->aConstraintUsage[j].omit = 1;
  if( seen[1]==0 ) return SQLITE_OK;
  pIdxInfo->estimatedCost = (double)20;
  pIdxInfo->estimatedRows = 20;
  j = seen[1];
  pIdxInfo->aConstraintUsage[j].argvIndex = 2;
  pIdxInfo->aConstraintUsage[j].omit = 1;
  return SQLITE_OK;
}

/* Create a new cursor for the pragma virtual table */
static int pragmaVtabOpen(sqlite3_vtab *pVtab, sqlite3_vtab_cursor **ppCursor){
  PragmaVtabCursor *pCsr;
  pCsr = (PragmaVtabCursor*)sqlite3_malloc(sizeof(*pCsr));
  if( pCsr==0 ) return SQLITE_NOMEM;
  memset(pCsr, 0, sizeof(PragmaVtabCursor));
  pCsr->base.pVtab = pVtab;
  *ppCursor = &pCsr->base;
  return SQLITE_OK;
}

/* Clear all content from pragma virtual table cursor. */
static void pragmaVtabCursorClear(PragmaVtabCursor *pCsr){
  int i;
  sqlite3_finalize(pCsr->pPragma);
  pCsr->pPragma = 0;
  for(i=0; i<ArraySize(pCsr->azArg); i++){
    sqlite3_free(pCsr->azArg[i]);
    pCsr->azArg[i] = 0;
  }
}

/* Close a pragma virtual table cursor */
static int pragmaVtabClose(sqlite3_vtab_cursor *cur){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)cur;
  pragmaVtabCursorClear(pCsr);
  return SQLITE_OK;
}

/* Advance the pragma virtual table cursor to the next row */
static int pragmaVtabNext(sqlite3_vtab_cursor *pVtabCursor){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
  int rc = SQLITE_OK;

  /* Increment the xRowid value */
  pCsr->iRowid++;
  if( pCsr->pPragma ){
    if( SQLITE_ROW!=sqlite3_step(pCsr->pPragma) ){
      rc = sqlite3_finalize(pCsr->pPragma);
      pCsr->pPragma = 0;
      pragmaVtabCursorClear(pCsr);
    }
  }
  return rc;
}

/* 
** Pragma virtual table module xFilter method.
*/
static int pragmaVtabFilter(
  sqlite3_vtab_cursor *pVtabCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
  PragmaVtab *pTab = (PragmaVtab*)(pVtabCursor->pVtab);
  int rc;
  int i;
  StrAccum acc;
  char *zSql;

  pragmaVtabCursorClear(pCsr);
  for(i=0; i<argc; i++){
    assert( i<ArraySize(pCsr->azArg) );
    pCsr->azArg[i] = sqlite3_mprintf("%s", sqlite3_value_text(argv[i]));
    if( pCsr->azArg[i]==0 ){
      return SQLITE_NOMEM;
    }
  }
  sqlite3StrAccumInit(&acc, 0, 0, 0, pTab->db->aLimit[SQLITE_MAX_SQL_LENGTH]);
  sqlite3StrAccumAppendAll(&acc, "PRAGMA ");
  if( pCsr->azArg[1] ){
    sqlite3XPrintf(&acc, "%Q.", pCsr->azArg[1]);
  }
  sqlite3StrAccumAppendAll(&acc, pTab->pName->zName);
  if( pCsr->azArg[0] ){
    sqlite3XPrintf(&acc, "=%Q", pCsr->azArg[0]);
  }
  zSql = sqlite3StrAccumFinish(&acc);
  if( zSql==0 ) return SQLITE_NOMEM;
  rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pPragma, 0);
  sqlite3_free(zSql);
  if( rc!=SQLITE_OK ){
    pTab->base.zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(pTab->db));
    return rc;
  }
  return pragmaVtabNext(pVtabCursor);
}

/*
** Pragma virtual table module xEof method.
*/
static int pragmaVtabEof(sqlite3_vtab_cursor *pVtabCursor){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
  return (pCsr->pPragma==0);
}

/* The xColumn method simply returns the corresponding column from
** the PRAGMA.  
*/
static int pragmaVtabColumn(
  sqlite3_vtab_cursor *pVtabCursor, 
  sqlite3_context *ctx, 
  int i
){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
  PragmaVtab *pTab = (PragmaVtab*)(pVtabCursor->pVtab);
  if( i<pTab->iHidden ){
    sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pPragma, i));
  }else{
    sqlite3_result_text(ctx, pCsr->azArg[i-pTab->iHidden],-1,SQLITE_TRANSIENT);
  }
  return SQLITE_OK;
}

/* 
** Pragma virtual table module xRowid method.
*/
static int pragmaVtabRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *p){
  PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
  *p = pCsr->iRowid;
  return SQLITE_OK;
}

/* The pragma virtual table object */
static const sqlite3_module pragmaVtabModule = {
  0,                           /* iVersion */
  0,                           /* xCreate - create a table */
  pragmaVtabConnect,           /* xConnect - connect to an existing table */
  pragmaVtabBestIndex,         /* xBestIndex - Determine search strategy */
  pragmaVtabDisconnect,        /* xDisconnect - Disconnect from a table */
  0,                           /* xDestroy - Drop a table */
  pragmaVtabOpen,              /* xOpen - open a cursor */
  pragmaVtabClose,             /* xClose - close a cursor */
  pragmaVtabFilter,            /* xFilter - configure scan constraints */
  pragmaVtabNext,              /* xNext - advance a cursor */
  pragmaVtabEof,               /* xEof */
  pragmaVtabColumn,            /* xColumn - read data */
  pragmaVtabRowid,             /* xRowid - read data */
  0,                           /* xUpdate - write data */
  0,                           /* xBegin - begin transaction */
  0,                           /* xSync - sync transaction */
  0,                           /* xCommit - commit transaction */
  0,                           /* xRollback - rollback transaction */
  0,                           /* xFindFunction - function overloading */
  0,                           /* xRename - rename the table */
  0,                           /* xSavepoint */
  0,                           /* xRelease */
  0                            /* xRollbackTo */
};

/*
** Check to see if zTabName is really the name of a pragma.  If it is,
** then register an eponymous virtual table for that pragma and return
** a pointer to the Module object for the new virtual table.
*/
Module *sqlite3PragmaVtabRegister(sqlite3 *db, const char *zName){
  const PragmaName *pName;
  assert( sqlite3_strnicmp(zName, "pragma_", 7)==0 );
  pName = pragmaLocate(zName+7);
  if( pName==0 ) return 0;
  if( (pName->mPragFlg & (PragFlg_Result0|PragFlg_Result1))==0 ) return 0;
  assert( sqlite3HashFind(&db->aModule, zName)==0 );
  return sqlite3VtabCreateModule(db, zName, &pragmaVtabModule, 0, 0);
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

#endif /* SQLITE_OMIT_PRAGMA */
Changes to src/pragma.h.
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124

125
126
127
128
129
130
131
  /*  44 */ "checkpointed",
  /*  45 */ "timeout",     /* Used by: busy_timeout */
  /*  46 */ "database",    /* Used by: lock_status */
  /*  47 */ "status",     
};

/* Definitions of all built-in pragmas */
static const struct sPragmaNames {
  const char *const zName; /* Name of pragma */
  u8 ePragTyp;             /* PragTyp_XXX value */
  u8 mPragFlg;             /* Zero or more PragFlg_XXX values */
  u8 iPragCName;           /* Start of column names in pragCName[] */
  u8 nPragCName;           /* Num of col names. 0 means use pragma name */
  u32 iArg;                /* Extra argument */
} aPragmaNames[] = {

#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_ENABLE_CEROD)
 {/* zName:     */ "activate_extensions",
  /* ePragTyp:  */ PragTyp_ACTIVATE_EXTENSIONS,
  /* ePragFlg:  */ 0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif







|






|
>







110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
  /*  44 */ "checkpointed",
  /*  45 */ "timeout",     /* Used by: busy_timeout */
  /*  46 */ "database",    /* Used by: lock_status */
  /*  47 */ "status",     
};

/* Definitions of all built-in pragmas */
typedef struct PragmaName {
  const char *const zName; /* Name of pragma */
  u8 ePragTyp;             /* PragTyp_XXX value */
  u8 mPragFlg;             /* Zero or more PragFlg_XXX values */
  u8 iPragCName;           /* Start of column names in pragCName[] */
  u8 nPragCName;           /* Num of col names. 0 means use pragma name */
  u32 iArg;                /* Extra argument */
} PragmaName;
static const PragmaName aPragmaName[] = {
#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_ENABLE_CEROD)
 {/* zName:     */ "activate_extensions",
  /* ePragTyp:  */ PragTyp_ACTIVATE_EXTENSIONS,
  /* ePragFlg:  */ 0,
  /* ColNames:  */ 0, 0,
  /* iArg:      */ 0 },
#endif
Changes to src/sqliteInt.h.
3559
3560
3561
3562
3563
3564
3565



3566
3567
3568
3569
3570
3571
3572
void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
void sqlite3ExprListDelete(sqlite3*, ExprList*);
u32 sqlite3ExprListFlags(const ExprList*);
int sqlite3Init(sqlite3*, char**);
int sqlite3InitCallback(void*, int, char**, char**);
void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);



void sqlite3ResetAllSchemasOfConnection(sqlite3*);
void sqlite3ResetOneSchema(sqlite3*,int);
void sqlite3CollapseDatabaseArray(sqlite3*);
void sqlite3CommitInternalChanges(sqlite3*);
void sqlite3DeleteColumnNames(sqlite3*,Table*);
int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*);







>
>
>







3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
void sqlite3ExprListDelete(sqlite3*, ExprList*);
u32 sqlite3ExprListFlags(const ExprList*);
int sqlite3Init(sqlite3*, char**);
int sqlite3InitCallback(void*, int, char**, char**);
void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
#ifndef SQLITE_OMIT_VIRTUALTABLE
Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
#endif
void sqlite3ResetAllSchemasOfConnection(sqlite3*);
void sqlite3ResetOneSchema(sqlite3*,int);
void sqlite3CollapseDatabaseArray(sqlite3*);
void sqlite3CommitInternalChanges(sqlite3*);
void sqlite3DeleteColumnNames(sqlite3*,Table*);
int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*);
4073
4074
4075
4076
4077
4078
4079







4080
4081
4082
4083
4084
4085
4086
   int sqlite3VtabCommit(sqlite3 *db);
   void sqlite3VtabLock(VTable *);
   void sqlite3VtabUnlock(VTable *);
   void sqlite3VtabUnlockList(sqlite3*);
   int sqlite3VtabSavepoint(sqlite3 *, int, int);
   void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
   VTable *sqlite3GetVTable(sqlite3*, Table*);







#  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
#endif
int sqlite3VtabEponymousTableInit(Parse*,Module*);
void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
void sqlite3VtabMakeWritable(Parse*,Table*);
void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
void sqlite3VtabFinishParse(Parse*, Token*);







>
>
>
>
>
>
>







4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
   int sqlite3VtabCommit(sqlite3 *db);
   void sqlite3VtabLock(VTable *);
   void sqlite3VtabUnlock(VTable *);
   void sqlite3VtabUnlockList(sqlite3*);
   int sqlite3VtabSavepoint(sqlite3 *, int, int);
   void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
   VTable *sqlite3GetVTable(sqlite3*, Table*);
   Module *sqlite3VtabCreateModule(
     sqlite3*,
     const char*,
     const sqlite3_module*,
     void*,
     void(*)(void*)
   );
#  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
#endif
int sqlite3VtabEponymousTableInit(Parse*,Module*);
void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
void sqlite3VtabMakeWritable(Parse*,Table*);
void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
void sqlite3VtabFinishParse(Parse*, Token*);
Changes to src/vtab.c.
23
24
25
26
27
28
29


































30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
*/
struct VtabCtx {
  VTable *pVTable;    /* The virtual table being constructed */
  Table *pTab;        /* The Table object to which the virtual table belongs */
  VtabCtx *pPrior;    /* Parent context (if any) */
  int bDeclared;      /* True after sqlite3_declare_vtab() is called */
};



































/*
** The actual function that does the work of creating a new module.
** This function implements the sqlite3_create_module() and
** sqlite3_create_module_v2() interfaces.
*/
static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
){
  int rc = SQLITE_OK;
  int nName;

  sqlite3_mutex_enter(db->mutex);
  nName = sqlite3Strlen30(zName);
  if( sqlite3HashFind(&db->aModule, zName) ){
    rc = SQLITE_MISUSE_BKPT;
  }else{
    Module *pMod;
    pMod = (Module *)sqlite3DbMallocRawNN(db, sizeof(Module) + nName + 1);
    if( pMod ){
      Module *pDel;
      char *zCopy = (char *)(&pMod[1]);
      memcpy(zCopy, zName, nName+1);
      pMod->zName = zCopy;
      pMod->pModule = pModule;
      pMod->pAux = pAux;
      pMod->xDestroy = xDestroy;
      pMod->pEpoTab = 0;
      pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod);
      assert( pDel==0 || pDel==pMod );
      if( pDel ){
        sqlite3OomFault(db);
        sqlite3DbFree(db, pDel);
      }
    }
  }
  rc = sqlite3ApiExit(db, rc);
  if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux);

  sqlite3_mutex_leave(db->mutex);
  return rc;
}


/*
** External API function used to create a new virtual-table module.







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>














<


<



<
<
<
<
<
|
<
<
<
<
<
<
<
<
<
<
<
<



<







23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77

78
79

80
81
82





83












84
85
86

87
88
89
90
91
92
93
*/
struct VtabCtx {
  VTable *pVTable;    /* The virtual table being constructed */
  Table *pTab;        /* The Table object to which the virtual table belongs */
  VtabCtx *pPrior;    /* Parent context (if any) */
  int bDeclared;      /* True after sqlite3_declare_vtab() is called */
};

/*
** Construct and install a Module object for a virtual table.  When this
** routine is called, it is guaranteed that all appropriate locks are held
** and the module is not already part of the connection.
*/
Module *sqlite3VtabCreateModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
){
  Module *pMod;
  int nName = sqlite3Strlen30(zName);
  pMod = (Module *)sqlite3DbMallocRawNN(db, sizeof(Module) + nName + 1);
  if( pMod ){
    Module *pDel;
    char *zCopy = (char *)(&pMod[1]);
    memcpy(zCopy, zName, nName+1);
    pMod->zName = zCopy;
    pMod->pModule = pModule;
    pMod->pAux = pAux;
    pMod->xDestroy = xDestroy;
    pMod->pEpoTab = 0;
    pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod);
    assert( pDel==0 || pDel==pMod );
    if( pDel ){
      sqlite3OomFault(db);
      sqlite3DbFree(db, pDel);
    }
  }
  return pMod;
}

/*
** The actual function that does the work of creating a new module.
** This function implements the sqlite3_create_module() and
** sqlite3_create_module_v2() interfaces.
*/
static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
){
  int rc = SQLITE_OK;


  sqlite3_mutex_enter(db->mutex);

  if( sqlite3HashFind(&db->aModule, zName) ){
    rc = SQLITE_MISUSE_BKPT;
  }else{





    (void)sqlite3VtabCreateModule(db, zName, pModule, pAux, xDestroy);












  }
  rc = sqlite3ApiExit(db, rc);
  if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux);

  sqlite3_mutex_leave(db->mutex);
  return rc;
}


/*
** External API function used to create a new virtual-table module.
Changes to tool/mkpragmatab.tcl.
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506

507
508
509
510
511
512
513
  }
}
puts $fd "\175;"

# Generate the lookup table
#
puts $fd "\n/* Definitions of all built-in pragmas */"
puts $fd "static const struct sPragmaNames \173"
puts $fd "  const char *const zName; /* Name of pragma */"
puts $fd "  u8 ePragTyp;             /* PragTyp_XXX value */"
puts $fd "  u8 mPragFlg;             /* Zero or more PragFlg_XXX values */"
puts $fd {  u8 iPragCName;           /* Start of column names in pragCName[] */}
puts $fd "  u8 nPragCName;          \
/* Num of col names. 0 means use pragma name */"
puts $fd "  u32 iArg;                /* Extra argument */"
puts $fd "\175 aPragmaNames\[\] = \173"


set current_if {}
set spacer [format {    %26s } {}]
foreach name $allnames {
  foreach {type arg if flag cx} $allbyname($name) break
  if {$cx==0} {
    set cy 0







|







|
>







491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
  }
}
puts $fd "\175;"

# Generate the lookup table
#
puts $fd "\n/* Definitions of all built-in pragmas */"
puts $fd "typedef struct PragmaName \173"
puts $fd "  const char *const zName; /* Name of pragma */"
puts $fd "  u8 ePragTyp;             /* PragTyp_XXX value */"
puts $fd "  u8 mPragFlg;             /* Zero or more PragFlg_XXX values */"
puts $fd {  u8 iPragCName;           /* Start of column names in pragCName[] */}
puts $fd "  u8 nPragCName;          \
/* Num of col names. 0 means use pragma name */"
puts $fd "  u32 iArg;                /* Extra argument */"
puts $fd "\175 PragmaName;"
puts $fd "static const PragmaName aPragmaName\[\] = \173"

set current_if {}
set spacer [format {    %26s } {}]
foreach name $allnames {
  foreach {type arg if flag cx} $allbyname($name) break
  if {$cx==0} {
    set cy 0