vdbe.c

最新的sqlite3.6.2源代码

** functions.
**
** The interface used by the implementation of the aforementioned functions
** to retrieve the collation sequence set by this opcode is not available
** publicly, only to user functions defined in func.c.
*/
case OP_CollSeq: {
  assert( pOp->p4type==P4_COLLSEQ );
  break;
}

/* Opcode: Function P1 P2 P3 P4 P5
**
** Invoke a user function (P4 is a pointer to a Function structure that
** defines the function) with P5 arguments taken from register P2 and
** successors.  The result of the function is stored in register P3.
** Register P3 must not be one of the function inputs.
**
** P1 is a 32-bit bitmask indicating whether or not each argument to the 
** function was determined to be constant at compile time. If the first
** argument was constant then bit 0 of P1 is set. This is used to determine
** whether meta data associated with a user function argument using the
** sqlite3_set_auxdata() API may be safely retained until the next
** invocation of this opcode.
**
** See also: AggStep and AggFinal
*/
case OP_Function: {
  int i;
  Mem *pArg;
  sqlite3_context ctx;
  sqlite3_value **apVal;
  int n = pOp->p5;

  apVal = p->apArg;
  assert( apVal || n==0 );

  assert( n==0 || (pOp->p2>0 && pOp->p2+n<=p->nMem) );
  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
  pArg = &p->aMem[pOp->p2];
  for(i=0; i<n; i++, pArg++){
    apVal[i] = pArg;
    storeTypeInfo(pArg, encoding);
    REGISTER_TRACE(pOp->p2, pArg);
  }

  assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
  if( pOp->p4type==P4_FUNCDEF ){
    ctx.pFunc = pOp->p4.pFunc;
    ctx.pVdbeFunc = 0;
  }else{
    ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
    ctx.pFunc = ctx.pVdbeFunc->pFunc;
  }

  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  pOut = &p->aMem[pOp->p3];
  ctx.s.flags = MEM_Null;
  ctx.s.db = db;
  ctx.s.xDel = 0;
  ctx.s.zMalloc = 0;

  /* The output cell may already have a buffer allocated. Move
  ** the pointer to ctx.s so in case the user-function can use
  ** the already allocated buffer instead of allocating a new one.
  */
  sqlite3VdbeMemMove(&ctx.s, pOut);
  MemSetTypeFlag(&ctx.s, MEM_Null);

  ctx.isError = 0;
  if( ctx.pFunc->needCollSeq ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = pOp[-1].p4.pColl;
  }
  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal);
  if( sqlite3SafetyOn(db) ){
    sqlite3VdbeMemRelease(&ctx.s);
    goto abort_due_to_misuse;
  }
  if( db->mallocFailed ){
    /* Even though a malloc() has failed, the implementation of the
    ** user function may have called an sqlite3_result_XXX() function
    ** to return a value. The following call releases any resources
    ** associated with such a value.
    **
    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
    ** fails also (the if(...) statement above). But if people are
    ** misusing sqlite, they have bigger problems than a leaked value.
    */
    sqlite3VdbeMemRelease(&ctx.s);
    goto no_mem;
  }

  /* If any auxiliary data functions have been called by this user function,
  ** immediately call the destructor for any non-static values.
  */
  if( ctx.pVdbeFunc ){
    sqlite3VdbeDeleteAuxData(ctx.pVdbeFunc, pOp->p1);
    pOp->p4.pVdbeFunc = ctx.pVdbeFunc;
    pOp->p4type = P4_VDBEFUNC;
  }

  /* If the function returned an error, throw an exception */
  if( ctx.isError ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&ctx.s));
    rc = ctx.isError;
  }

  /* Copy the result of the function into register P3 */
  sqlite3VdbeChangeEncoding(&ctx.s, encoding);
  sqlite3VdbeMemMove(pOut, &ctx.s);
  if( sqlite3VdbeMemTooBig(pOut) ){
    goto too_big;
  }
  REGISTER_TRACE(pOp->p3, pOut);
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: BitAnd P1 P2 P3 * *
**
** Take the bit-wise AND of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: BitOr P1 P2 P3 * *
**
** Take the bit-wise OR of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftLeft P1 P2 P3 * *
**
** Shift the integer value in register P2 to the left by the
** number of bits specified by the integer in regiser P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftRight P1 P2 P3 * *
**
** Shift the integer value in register P2 to the right by the
** number of bits specified by the integer in register P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */
case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
  i64 a, b;

  if( (pIn1->flags | pIn2->flags) & MEM_Null ){
    sqlite3VdbeMemSetNull(pOut);
    break;
  }
  a = sqlite3VdbeIntValue(pIn2);
  b = sqlite3VdbeIntValue(pIn1);
  switch( pOp->opcode ){
    case OP_BitAnd:      a &= b;     break;
    case OP_BitOr:       a |= b;     break;
    case OP_ShiftLeft:   a <<= b;    break;
    default:  assert( pOp->opcode==OP_ShiftRight );
                         a >>= b;    break;
  }
  pOut->u.i = a;
  MemSetTypeFlag(pOut, MEM_Int);
  break;
}

/* Opcode: AddImm  P1 P2 * * *
** 
** Add the constant P2 to the value in register P1.
** The result is always an integer.
**
** To force any register to be an integer, just add 0.
*/
case OP_AddImm: {            /* in1 */
  sqlite3VdbeMemIntegerify(pIn1);
  pIn1->u.i += pOp->p2;
  break;
}

/* Opcode: ForceInt P1 P2 P3 * *
**
** Convert value in register P1 into an integer.  If the value 
** in P1 is not numeric (meaning that is is a NULL or a string that
** does not look like an integer or floating point number) then
** jump to P2.  If the value in P1 is numeric then
** convert it into the least integer that is greater than or equal to its
** current value if P3==0, or to the least integer that is strictly
** greater than its current value if P3==1.
*/
case OP_ForceInt: {            /* jump, in1 */
  i64 v;
  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
  if( (pIn1->flags & (MEM_Int|MEM_Real))==0 ){
    pc = pOp->p2 - 1;
    break;
  }
  if( pIn1->flags & MEM_Int ){
    v = pIn1->u.i + (pOp->p3!=0);
  }else{
    assert( pIn1->flags & MEM_Real );
    v = (sqlite3_int64)pIn1->r;
    if( pIn1->r>(double)v ) v++;
    if( pOp->p3 && pIn1->r==(double)v ) v++;
  }
  pIn1->u.i = v;
  MemSetTypeFlag(pIn1, MEM_Int);
  break;
}

/* Opcode: MustBeInt P1 P2 * * *
** 
** Force the value in register P1 to be an integer.  If the value
** in P1 is not an integer and cannot be converted into an integer
** without data loss, then jump immediately to P2, or if P2==0
** raise an SQLITE_MISMATCH exception.
*/
case OP_MustBeInt: {            /* jump, in1 */
  applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
  if( (pIn1->flags & MEM_Int)==0 ){
    if( pOp->p2==0 ){
      rc = SQLITE_MISMATCH;
      goto abort_due_to_error;
    }else{
      pc = pOp->p2 - 1;
    }
  }else{
    MemSetTypeFlag(pIn1, MEM_Int);
  }
  break;
}

/* Opcode: RealAffinity P1 * * * *
**
** If register P1 holds an integer convert it to a real value.
**
** This opcode is used when extracting information from a column that
** has REAL affinity.  Such column values may still be stored as
** integers, for space efficiency, but after extraction we want them
** to have only a real value.
*/
case OP_RealAffinity: {                  /* in1 */
  if( pIn1->flags & MEM_Int ){
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}

#ifndef SQLITE_OMIT_CAST
/* Opcode: ToText P1 * * * *
**
** Force the value in register P1 to be text.
** If the value is numeric, convert it to a string using the
** equivalent of printf().  Blob values are unchanged and
** are afterwards simply interpreted as text.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
  if( pIn1->flags & MEM_Null ) break;
  assert( MEM_Str==(MEM_Blob>>3) );
  pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
  applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
  rc = ExpandBlob(pIn1);
  assert( pIn1->flags & MEM_Str || db->mallocFailed );
  pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob);
  UPDATE_MAX_BLOBSIZE(pIn1);
  break;
}

/* Opcode: ToBlob P1 * * * *
**
** Force the value in register P1 to be a BLOB.
** If the value is numeric, convert it to a string first.
** Strings are simply reinterpreted as blobs with no change
** to the underlying data.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
  if( pIn1->flags & MEM_Null ) break;
  if( (pIn1->flags & MEM_Blob)==0 ){
    applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
    assert( pIn1->flags & MEM_Str || db->mallocFailed );
  }
  MemSetTypeFlag(pIn1, MEM_Blob);
  UPDATE_MAX_BLOBSIZE(pIn1);
  break;
}

/* Opcode: ToNumeric P1 * * * *
**
** Force the value in register P1 to be numeric (either an
** integer or a floating-point number.)
** If the value is text or blob, try to convert it to an using the
** equivalent of atoi() or atof() and store 0 if no such conversion 
** is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
  if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
    sqlite3VdbeMemNumerify(pIn1);
  }
  break;
}
#endif /* SQLITE_OMIT_CAST */

/* Opcode: ToInt P1 * * * *
**
** Force the value in register P1 be an integer.  If
** The value is currently a real number, drop its fractional part.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0 if no such conversion is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
  if( (pIn1->flags & MEM_Null)==0 ){
    sqlite3VdbeMemIntegerify(pIn1);
  }
  break;
}

#ifndef SQLITE_OMIT_CAST
/* Opcode: ToReal P1 * * * *
**
** Force the value in register P1 to be a floating point number.
** If The value is currently an integer, convert it.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0.0 if no such conversion is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
  if( (pIn1->flags & MEM_Null)==0 ){
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}
#endif /* SQLITE_OMIT_CAST */

/* Opcode: Lt P1 P2 P3 P4 P5
**
** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
** jump to address P2.  
**
** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
** bit is clear then fall thru if either operand is NULL.
**
** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 
** to coerce both inputs according to this affinity before the
** comparison is made. If the SQLITE_AFF_MASK is 0x00, then numeric
** affinity is used. Note that the affinity conversions are stored
** back into the input registers P1 and P3.  So this opcode can cause
** persistent changes to registers P1 and P3.
**
** Once any conversions have taken place, and neither value is NULL, 
** the values are compared. If both values are blobs then memcmp() is
** used to determine the results of the comparison.  If both values
** are text, then the appropriate collating function specified in
** P4 is  used to do the comparison.  If P4 is not specified then
** memcmp() is used to compare text string.  If both values are
** numeric, then a numeric comparison is used. If the two values
** are of different types, then numbers are considered less than
** strings and strings are considered less than blobs.
**
** If the SQLITE_STOREP2 bit of P5 is set, then do not jump.  Instead,
** store a boolean result (either 0, or 1, or NULL) in register P2.
*/
/* Opcode: Ne P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the operands in registers P1 and P3 are not equal.  See the Lt opcode for
** additional information.
*/
/* Opcode: Eq P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the operands in registers P1 and P3 are equal.
** See the Lt opcode for additional information.
*/
/* Opcode: Le P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is less than or equal to the content of
** register P1.  See the Lt opcode for additional information.
*/
/* Opcode: Gt P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than the content of
** register P1.  See the Lt opcode for additional information.
*/
/* Opcode: Ge P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than or equal to the content of
** register P1.  See the Lt opcode for additional information.
*/
case OP_Eq:               /* same as TK_EQ, jump, in1, in3 */
case OP_Ne:               /* same as TK_NE, jump, in1, in3 */
case OP_Lt:               /* same as TK_LT, jump, in1, in3 */
case OP_Le:               /* same as TK_LE, jump, in1, in3 */
case OP_Gt:               /* same as TK_GT, jump, in1, in3 */
case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
  int flags;
  int res;
  char affinity;

  flags = pIn1->flags|pIn3->flags;

  if( flags&MEM_Null ){