SQLite

/*
** Return a JsonNode and all its descendants as a JSON string.
*/
static void jsonReturnJson(
  JsonParse *pParse,          /* The complete JSON */
  JsonNode *pNode,            /* Node to return */
  sqlite3_context *pCtx,      /* Return value for this function */
  int bGenerateAlt,           /* Also store the rendered text in zAlt */
  int omitSubtype             /* Do not call sqlite3_result_subtype() */
){
  JsonString s;
  if( pParse->oom ){
    sqlite3_result_error_nomem(pCtx);
    return;
  }
  if( pParse->nErr==0 ){
    jsonInit(&s, pCtx);
    jsonRenderNode(pParse, pNode, &s);
    if( bGenerateAlt && pParse->zAlt==0 && jsonForceRCStr(&s) ){
      pParse->zAlt = sqlite3RCStrRef(s.zBuf);
      pParse->nAlt = s.nUsed;
    }
    jsonResult(&s);
    if( !omitSubtype ) sqlite3_result_subtype(pCtx, JSON_SUBTYPE);
  }
}

/*
** Translate a single byte of Hex into an integer.
** This routine only works if h really is a valid hexadecimal
** character:  0..9a..fA..F

/*
** Make the JsonNode the return value of the function.
*/
static void jsonReturn(
  JsonParse *pParse,          /* Complete JSON parse tree */
  JsonNode *pNode,            /* Node to return */
  sqlite3_context *pCtx,      /* Return value for this function */
  int omitSubtype             /* Do not call sqlite3_result_subtype() */
){
  switch( pNode->eType ){
    default: {
      assert( pNode->eType==JSON_NULL );
      sqlite3_result_null(pCtx);
      break;
    }

        zOut[j] = 0;
        sqlite3_result_text(pCtx, zOut, j, sqlite3_free);
      }
      break;
    }
    case JSON_ARRAY:
    case JSON_OBJECT: {
      jsonReturnJson(pParse, pNode, pCtx, 0, omitSubtype);
      break;
    }
  }
}

/* Forward reference */
static int jsonParseAddNode(JsonParse*,u32,u32,const char*);

  printf("hasNonstd = %u\n", p->hasNonstd);
  printf("useMod    = %u\n", p->useMod);
  printf("hasMod    = %u\n", p->hasMod);
  printf("nJPRef    = %u\n", p->nJPRef);
  printf("iSubst    = %u\n", p->iSubst);
  printf("iHold     = %u\n", p->iHold);
  jsonDebugPrintNodeEntries(p->aNode, p->nNode);
  jsonReturnJson(p, p->aNode, ctx, 1, 0);
}

/*
** The json_test1(JSON) function return true (1) if the input is JSON
** text generated by another json function.  It returns (0) if the input
** is not known to be JSON.
*/

        pNode = jx.bErr ? 0 : jsonLookup(p, jx.zBuf, 0, ctx);
        jsonReset(&jx);
      }else{
        pNode = jsonLookup(p, zPath, 0, ctx);
      }
      if( pNode ){
        if( flags & JSON_JSON ){
          jsonReturnJson(p, pNode, ctx, 0, 0);
        }else{
          jsonReturn(p, pNode, ctx, 1);

        }
      }
    }else{
      pNode = jsonLookup(p, zPath, 0, ctx);
      if( p->nErr==0 && pNode ) jsonReturn(p, pNode, ctx, 0);
    }
  }else{
    /* Two or more PATH arguments results in a JSON array with each
    ** element of the array being the value selected by one of the PATHs */
    int i;
    jsonInit(&jx, ctx);
    jsonAppendChar(&jx, '[');

  pX->useMod = 1;
  pY->useMod = 1;
  pResult = jsonMergePatch(pX, 0, pY->aNode);
  assert( pResult!=0 || pX->oom );
  if( pResult && pX->oom==0 ){
    jsonDebugPrintParse(pX);
    jsonDebugPrintNode(pResult);
    jsonReturnJson(pX, pResult, ctx, 0, 0);
  }else{
    sqlite3_result_error_nomem(ctx);
  }
}


/*

    if( pNode ){
      pNode->jnFlags |= JNODE_REMOVE;
      pParse->hasMod = 1;
      pParse->useMod = 1;
    }
  }
  if( (pParse->aNode[0].jnFlags & JNODE_REMOVE)==0 ){
    jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
  }
remove_done:
  jsonDebugPrintParse(p);
}

/*
** Substitute the value at iNode with the pValue parameter.

    pParse->useMod = 1;
    pNode = jsonLookup(pParse, zPath, 0, ctx);
    if( pParse->nErr ) goto replace_err;
    if( pNode ){
      jsonReplaceNode(ctx, pParse, (u32)(pNode - pParse->aNode), argv[i+1]);
    }
  }
  jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
replace_err:
  jsonDebugPrintParse(pParse);
  jsonParseFree(pParse);
}


/*

    }else if( pParse->nErr ){
      goto jsonSetDone;
    }else if( pNode && (bApnd || bIsSet) ){
      jsonReplaceNode(ctx, pParse, (u32)(pNode - pParse->aNode), argv[i+1]);
    }
  }
  jsonDebugPrintParse(pParse);
  jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
jsonSetDone:
  jsonParseFree(pParse);
}

/*
** json_type(JSON)
** json_type(JSON, PATH)

){
  JsonEachCursor *p = (JsonEachCursor*)cur;
  JsonNode *pThis = &p->sParse.aNode[p->i];
  switch( i ){
    case JEACH_KEY: {
      if( p->i==0 ) break;
      if( p->eType==JSON_OBJECT ){
        jsonReturn(&p->sParse, pThis, ctx, 0);
      }else if( p->eType==JSON_ARRAY ){
        u32 iKey;
        if( p->bRecursive ){
          if( p->iRowid==0 ) break;
          assert( p->sParse.aNode[p->sParse.aUp[p->i]].eU==3 );
          iKey = p->sParse.aNode[p->sParse.aUp[p->i]].u.iKey;
        }else{
          iKey = p->iRowid;
        }
        sqlite3_result_int64(ctx, (sqlite3_int64)iKey);
      }
      break;
    }
    case JEACH_VALUE: {
      if( pThis->jnFlags & JNODE_LABEL ) pThis++;
      jsonReturn(&p->sParse, pThis, ctx, 0);
      break;
    }
    case JEACH_TYPE: {
      if( pThis->jnFlags & JNODE_LABEL ) pThis++;
      sqlite3_result_text(ctx, jsonType[pThis->eType], -1, SQLITE_STATIC);
      break;
    }
    case JEACH_ATOM: {
      if( pThis->jnFlags & JNODE_LABEL ) pThis++;
      if( pThis->eType>=JSON_ARRAY ) break;
      jsonReturn(&p->sParse, pThis, ctx, 0);
      break;
    }
    case JEACH_ID: {
      sqlite3_result_int64(ctx,
         (sqlite3_int64)p->i + ((pThis->jnFlags & JNODE_LABEL)!=0));
      break;
    }

/*
** Register JSON functions.
*/
void sqlite3RegisterJsonFunctions(void){
#ifndef SQLITE_OMIT_JSON
  static FuncDef aJsonFunc[] = {
    /*                     calls sqlite3_result_subtype()                    */
    /*                                  |                                    */
    /*              Uses cache ______   |   __ calls sqlite3_value_subtype() */
    /*                               |  |  |                                 */
    /*          Num args _________   |  |  |   ___ Flags                     */
    /*                            |  |  |  |  |                              */
    /*                            |  |  |  |  |                              */
    JFUNCTION(json,               1, 1, 1, 0, 0,          jsonRemoveFunc),
    JFUNCTION(json_array,        -1, 0, 1, 1, 0,          jsonArrayFunc),
    JFUNCTION(json_array_length,  1, 1, 0, 0, 0,          jsonArrayLengthFunc),
    JFUNCTION(json_array_length,  2, 1, 0, 0, 0,          jsonArrayLengthFunc),
    JFUNCTION(json_error_position,1, 1, 0, 0, 0,          jsonErrorFunc),
    JFUNCTION(json_extract,      -1, 1, 1, 0, 0,          jsonExtractFunc),
    JFUNCTION(->,                 2, 1, 1, 0, JSON_JSON,  jsonExtractFunc),
    JFUNCTION(->>,                2, 1, 0, 0, JSON_SQL,   jsonExtractFunc),
    JFUNCTION(json_insert,       -1, 1, 1, 1, 0,          jsonSetFunc),
    JFUNCTION(json_object,       -1, 0, 1, 1, 0,          jsonObjectFunc),
    JFUNCTION(json_patch,         2, 1, 1, 0, 0,          jsonPatchFunc),
    JFUNCTION(json_quote,         1, 0, 1, 1, 0,          jsonQuoteFunc),
    JFUNCTION(json_remove,       -1, 1, 1, 0, 0,          jsonRemoveFunc),
    JFUNCTION(json_replace,      -1, 1, 1, 1, 0,          jsonReplaceFunc),
    JFUNCTION(json_set,          -1, 1, 1, 1, JSON_ISSET, jsonSetFunc),
    JFUNCTION(json_type,          1, 1, 0, 0, 0,          jsonTypeFunc),
    JFUNCTION(json_type,          2, 1, 0, 0, 0,          jsonTypeFunc),
    JFUNCTION(json_valid,         1, 1, 0, 0, 0,          jsonValidFunc),
#if SQLITE_DEBUG
    JFUNCTION(json_parse,         1, 1, 1, 0, 0,          jsonParseFunc),
    JFUNCTION(json_test1,         1, 1, 0, 1, 0,          jsonTest1Func),
#endif
    WAGGREGATE(json_group_array,  1, 0, 0,
       jsonArrayStep, jsonArrayFinal, jsonArrayValue, jsonGroupInverse,
       SQLITE_SUBTYPE|SQLITE_RESULT_SUBTYPE|SQLITE_UTF8|
       SQLITE_DETERMINISTIC),
    WAGGREGATE(json_group_object, 2, 0, 0,
       jsonObjectStep, jsonObjectFinal, jsonObjectValue, jsonGroupInverse,
       SQLITE_SUBTYPE|SQLITE_RESULT_SUBTYPE|SQLITE_UTF8|
       SQLITE_DETERMINISTIC)
  };
  sqlite3InsertBuiltinFuncs(aJsonFunc, ArraySize(aJsonFunc));
#endif
}

#if  !defined(SQLITE_OMIT_VIRTUALTABLE) && !defined(SQLITE_OMIT_JSON)
/*

  ){
    return SQLITE_MISUSE_BKPT;
  }

  assert( SQLITE_FUNC_CONSTANT==SQLITE_DETERMINISTIC );
  assert( SQLITE_FUNC_DIRECT==SQLITE_DIRECTONLY );
  extraFlags = enc &  (SQLITE_DETERMINISTIC|SQLITE_DIRECTONLY|
                       SQLITE_SUBTYPE|SQLITE_INNOCUOUS|SQLITE_RESULT_SUBTYPE);
  enc &= (SQLITE_FUNC_ENCMASK|SQLITE_ANY);

  /* The SQLITE_INNOCUOUS flag is the same bit as SQLITE_FUNC_UNSAFE.  But
  ** the meaning is inverted.  So flip the bit. */
  assert( SQLITE_FUNC_UNSAFE==SQLITE_INNOCUOUS );
  extraFlags ^= SQLITE_FUNC_UNSAFE;  /* tag-20230109-1 */

** are innocuous.  Developers are advised to avoid using the
** SQLITE_INNOCUOUS flag for application-defined functions unless the
** function has been carefully audited and found to be free of potentially
** security-adverse side-effects and information-leaks.
** </dd>
**
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
** This flag instructs SQLite to omit some corner-case optimizations that
** might disrupt the operation of the [sqlite3_value_subtype()] function,
** causing it to return zero rather than the correct subtype().
** SQL functions that invokes [sqlite3_value_subtype()] should have this
** property.  If the SQLITE_SUBTYPE property is omitted, then the return
** value from [sqlite3_value_subtype()] might sometimes be zero even though
** a non-zero subtype was specified by the function argument expression.
**
** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
** result.
** Every function that invokes [sqlite3_result_subtype()] should have this
** property.  If it does not, then the call to [sqlite3_result_subtype()]
** might become a no-op if the function is used as term in an
** [expression index].  On the other hand, SQL functions that never invoke
** [sqlite3_result_subtype()] should avoid setting this property, as the
** purpose of this property is to disable certain optimizations that are
** incompatible with subtypes.
** </dd>
** </dl>
*/
#define SQLITE_DETERMINISTIC    0x000000800
#define SQLITE_DIRECTONLY       0x000080000
#define SQLITE_SUBTYPE          0x000100000
#define SQLITE_INNOCUOUS        0x000200000
#define SQLITE_RESULT_SUBTYPE   0x001000000

/*
** CAPI3REF: Deprecated Functions
** DEPRECATED
**
** These functions are [deprecated].  In order to maintain
** backwards compatibility with older code, these functions continue

** METHOD: sqlite3_value
**
** The sqlite3_value_subtype(V) function returns the subtype for
** an [application-defined SQL function] argument V.  The subtype
** information can be used to pass a limited amount of context from
** one SQL function to another.  Use the [sqlite3_result_subtype()]
** routine to set the subtype for the return value of an SQL function.
**
** Every [application-defined SQL function] that invoke this interface
** should include the [SQLITE_SUBTYPE] property in the text
** encoding argument when the function is [sqlite3_create_function|registered].
** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
** might return zero instead of the upstream subtype in some corner cases.
*/
unsigned int sqlite3_value_subtype(sqlite3_value*);

/*
** CAPI3REF: Copy And Free SQL Values
** METHOD: sqlite3_value
**

** The sqlite3_result_subtype(C,T) function causes the subtype of
** the result from the [application-defined SQL function] with
** [sqlite3_context] C to be the value T.  Only the lower 8 bits
** of the subtype T are preserved in current versions of SQLite;
** higher order bits are discarded.
** The number of subtype bytes preserved by SQLite might increase
** in future releases of SQLite.
**
** Every [application-defined SQL function] that invokes this interface
** should include the [SQLITE_RESULT_SUBTYPE] property in its
** text encoding argument when the SQL function is
** [sqlite3_create_function|registered].  If the [SQLITE_RESULT_SUBTYPE]
** property is omitted from the function that invokes sqlite3_result_subtype(),
** then in some cases the sqlite3_result_subtype() might fail to set
** the result subtype.
**
** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
** SQL function that invokes the sqlite3_result_subtype() interface
** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
** an error.  Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
** by default.
*/
void sqlite3_result_subtype(sqlite3_context*,unsigned int);

/*
** CAPI3REF: Define New Collating Sequences
** METHOD: sqlite3
**

#define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                    ** single query - might change over time */
#define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
#define SQLITE_FUNC_RUNONLY  0x8000 /* Cannot be used by valueFromFunction */
#define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
#define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
#define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
/* SQLITE_SUBTYPE            0x00100000 // Consumer of subtypes */
#define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
#define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
#define SQLITE_FUNC_BUILTIN  0x00800000 /* This is a built-in function */
/*  SQLITE_RESULT_SUBTYPE    0x01000000 // Generator of subtypes */
#define SQLITE_FUNC_ANYORDER 0x08000000 /* count/min/max aggregate */

/* Identifier numbers for each in-line function */
#define INLINEFUNC_coalesce             0
#define INLINEFUNC_implies_nonnull_row  1
#define INLINEFUNC_expr_implies_expr    2
#define INLINEFUNC_expr_compare         3

   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_DIRECTONLY|SQLITE_FUNC_UNSAFE, \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define MFUNCTION(zName, nArg, xPtr, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
   xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
#define JFUNCTION(zName, nArg, bUseCache, bWS, bRS, iArg, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|SQLITE_FUNC_CONSTANT|\
   SQLITE_UTF8|((bUseCache)*SQLITE_FUNC_RUNONLY)|\
   ((bRS)*SQLITE_SUBTYPE)|((bWS)*SQLITE_RESULT_SUBTYPE), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define INLINE_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
#define TEST_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\

  sqlite3VdbeMemSetPointer(pOut, pPtr, zPType, xDestructor);
}
void sqlite3_result_subtype(sqlite3_context *pCtx, unsigned int eSubtype){
  Mem *pOut;
#ifdef SQLITE_ENABLE_API_ARMOR
  if( pCtx==0 ) return;
#endif
#if defined(SQLITE_STRICT_SUBTYPE) && SQLITE_STRICT_SUBTYPE+0!=0
  if( pCtx->pFunc!=0
   && (pCtx->pFunc->funcFlags & SQLITE_RESULT_SUBTYPE)==0
  ){
    char zErr[200];
    sqlite3_snprintf(sizeof(zErr), zErr,
                     "misuse of sqlite3_result_subtype() by %s()", 
                     pCtx->pFunc->zName);
    sqlite3_result_error(pCtx, zErr, -1);
    return;
  }
#endif /* SQLITE_STRICT_SUBTYPE */
  pOut = pCtx->pOut;
  assert( sqlite3_mutex_held(pOut->db->mutex) );
  pOut->eSubtype = eSubtype & 0xff;
  pOut->flags |= MEM_Subtype;
}
void sqlite3_result_text(
  sqlite3_context *pCtx,

    }else if( j>=0 && (pTab->aCol[j].colFlags & COLFLAG_VIRTUAL)!=0 ){
      pExpr = sqlite3ColumnExpr(pTab, &pTab->aCol[j]);
      bMaybeNullRow = 0;
    }else{
      continue;
    }
    if( sqlite3ExprIsConstant(pExpr) ) continue;
    if( pExpr->op==TK_FUNCTION ){
      /* Functions that might set a subtype should not be replaced by the
      ** value taken from an expression index since the index omits the
      ** subtype.  https://sqlite.org/forum/forumpost/68d284c86b082c3e */
      int n;
      FuncDef *pDef;
      sqlite3 *db = pParse->db;
      assert( ExprUseXList(pExpr) );
      n = ALWAYS(pExpr->x.pList) ? pExpr->x.pList->nExpr : 0;
      pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0);
      if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){
        continue;
      }
    }
    p = sqlite3DbMallocRaw(pParse->db,  sizeof(IndexedExpr));
    if( p==0 ) break;
    p->pIENext = pParse->pIdxEpr;
#ifdef WHERETRACE_ENABLED
    if( sqlite3WhereTrace & 0x200 ){
      sqlite3DebugPrintf("New pParse->pIdxEpr term {%d,%d}\n", iIdxCur, i);
      if( sqlite3WhereTrace & 0x5000 ) sqlite3ShowExpr(pExpr);

    ** window function - one for the accumulator, another for interim
    ** results.  */
    for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
      ExprList *pArgs;
      assert( ExprUseXList(pWin->pOwner) );
      assert( pWin->pWFunc!=0 );
      pArgs = pWin->pOwner->x.pList;
      if( pWin->pWFunc->funcFlags & SQLITE_SUBTYPE ){
        selectWindowRewriteEList(pParse, pMWin, pSrc, pArgs, pTab, &pSublist);
        pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
        pWin->bExprArgs = 1;
      }else{
        pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
        pSublist = exprListAppendList(pParse, pSublist, pArgs, 0);
      }

    JOIN (SELECT t1.tag AS "tag", t2.type AS "type",
                 MAX(t2.value) AS "max_value"
            FROM t1
                 JOIN t2 ON t2.t1_id = t1.id
           GROUP BY t2.type, t1.tag
         ) v ON v.type = 0 AND v.tag = u.tag;
} {7 100 8 101}

# 2023-11-08 Forum post https://sqlite.org/forum/forumpost/68d284c86b082c3e
#
# Functions that return subtypes and that are indexed cannot be used to
# cover function calls from the main table, since the indexed value does
# not know the subtype.
#
reset_db
do_execsql_test indexexpr1-2300 {
  CREATE TABLE t1(x INT, y TEXT);
  INSERT INTO t1(x,y) VALUES(1,'{b:5}');
  CREATE INDEX t1j ON t1(json(y));
  SELECT json_insert('{}', '$.a', json(y)) FROM t1;
} {{{"a":{"b":5}}}}

finish_test