SQLite

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.147 2007/05/08 12:12:17 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/* #include <math.h> */
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *z;
  const unsigned char *z2;
  int i;
  int len;
  i64 p1, p2;

  assert( argc==3 );
  z = sqlite3_value_text(argv[0]);
  if( z==0 ) return;
  p1 = sqlite3_value_int(argv[1]);
  p2 = sqlite3_value_int(argv[2]);
  for(len=0, z2=z; *z2; z2++){ if( (0xc0&*z2)!=0x80 ) len++; }

  int argc,
  sqlite3_value **argv
){
  int n;
  unsigned char *p;
  assert( argc==1 );
  n = sqlite3_value_int(argv[0]);
  if( n<1 ){
    n = 1;
  }
  if( n>SQLITE_MAX_LENGTH ){
    sqlite3_result_error(context, "randomblob() too large", -1);
    return;
  }
  p = sqliteMalloc(n);
  if( p ){
    sqlite3Randomness(n, p);
    sqlite3_result_blob(context, (char*)p, n, sqlite3FreeX);
  }
}

      break;
    }
    case SQLITE_BLOB: {
      char *zText = 0;
      int nBlob = sqlite3_value_bytes(argv[0]);
      char const *zBlob = sqlite3_value_blob(argv[0]);

      if( 2*nBlob+4>SQLITE_MAX_LENGTH ){
        sqlite3_result_error(context, "BLOB too big to quote", -1);
        return;
      }
      zText = (char *)sqliteMalloc((2*nBlob)+4); 
      if( !zText ){
        sqlite3_result_error(context, "out of memory", -1);
      }else{
        int i;
        for(i=0; i<nBlob; i++){
          zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F];
          zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F];
        }
        zText[(nBlob*2)+2] = '\'';
        zText[(nBlob*2)+3] = '\0';
        zText[0] = 'X';
        zText[1] = '\'';
        sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT);
        sqliteFree(zText);
      }
      break;
    }
    case SQLITE_TEXT: {
      int i,j;
      u64 n;
      const unsigned char *zArg = sqlite3_value_text(argv[0]);
      char *z;

      if( zArg==0 ) return;
      for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; }
      if( i+n+3>SQLITE_MAX_LENGTH ){
        sqlite3_result_error(context, "string too big to quote", -1);
        return;
      }
      z = sqliteMalloc( i+n+3 );
      if( z==0 ) return;
      z[0] = '\'';
      for(i=0, j=1; zArg[i]; i++){
        z[j++] = zArg[i];
        if( zArg[i]=='\'' ){
          z[j++] = '\'';

  sqlite3_value **argv
){
  int i, n;
  const unsigned char *pBlob;
  char *zHex, *z;
  assert( argc==1 );
  n = sqlite3_value_bytes(argv[0]);
  if( n*2+1>SQLITE_MAX_LENGTH ){
    sqlite3_result_error(context, "BLOB too big to convert to hex", -1);
    return;
  }
  pBlob = sqlite3_value_blob(argv[0]);
  z = zHex = sqlite3_malloc(n*2 + 1);
  if( zHex==0 ) return;
  for(i=0; i<n; i++, pBlob++){
    unsigned char c = *pBlob;
    *(z++) = hexdigits[(c>>4)&0xf];
    *(z++) = hexdigits[c&0xf];

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.375 2007/05/08 12:12:17 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The version of the library

    case SQLITE_INTERRUPT:  z = "interrupted";                           break;
    case SQLITE_IOERR:      z = "disk I/O error";                        break;
    case SQLITE_CORRUPT:    z = "database disk image is malformed";      break;
    case SQLITE_FULL:       z = "database or disk is full";              break;
    case SQLITE_CANTOPEN:   z = "unable to open database file";          break;
    case SQLITE_EMPTY:      z = "table contains no data";                break;
    case SQLITE_SCHEMA:     z = "database schema has changed";           break;
    case SQLITE_TOOBIG:     z = "String or BLOB exceeded size limit";    break;
    case SQLITE_CONSTRAINT: z = "constraint failed";                     break;
    case SQLITE_MISMATCH:   z = "datatype mismatch";                     break;
    case SQLITE_MISUSE:     z = "library routine called out of sequence";break;
    case SQLITE_NOLFS:      z = "kernel lacks large file support";       break;
    case SQLITE_AUTH:       z = "authorization denied";                  break;
    case SQLITE_FORMAT:     z = "auxiliary database format error";       break;
    case SQLITE_RANGE:      z = "bind or column index out of range";     break;

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.609 2007/05/08 12:12:17 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*

** P3 points to a nul terminated UTF-8 string. This opcode is transformed 
** into an OP_String before it is executed for the first time.
*/
case OP_String8: {         /* same as TK_STRING */
  assert( pOp->p3!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = strlen(pOp->p3);
  assert( SQLITE_MAX_SQL_LENGTH < SQLITE_MAX_LENGTH );
  assert( pOp->p1 < SQLITE_MAX_LENGTH );

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p3, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, encoding) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pTos) ) goto no_mem;
    pTos->flags &= ~(MEM_Dyn);
    pTos->flags |= MEM_Static;
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3type = P3_DYNAMIC;
    pOp->p3 = pTos->z;
    pOp->p1 = pTos->n;
    assert( pOp->p1 < SQLITE_MAX_LENGTH ); /* Due to SQLITE_MAX_SQL_LENGTH */
    break;
  }
#endif
  /* Otherwise fall through to the next case, OP_String */
}
  
/* Opcode: String P1 * P3
**
** The string value P3 of length P1 (bytes) is pushed onto the stack.
*/
case OP_String: {
  assert( pOp->p1 < SQLITE_MAX_LENGTH ); /* Due to SQLITE_MAX_SQL_LENGTH */
  pTos++;
  assert( pOp->p3!=0 );
  pTos->flags = MEM_Str|MEM_Static|MEM_Term;
  pTos->z = pOp->p3;
  pTos->n = pOp->p1;
  pTos->enc = encoding;
  break;

**
** The first time this instruction executes, in transforms itself into a
** 'Blob' opcode with a binary blob as P3.
*/
case OP_HexBlob: {            /* same as TK_BLOB */
  pOp->opcode = OP_Blob;
  pOp->p1 = strlen(pOp->p3)/2;
  assert( SQLITE_MAX_SQL_LENGTH < SQLITE_MAX_LENGTH );
  assert( pOp->p1 < SQLITE_MAX_LENGTH );
  if( pOp->p1 ){
    char *zBlob = sqlite3HexToBlob(pOp->p3);
    if( !zBlob ) goto no_mem;
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3 = zBlob;

** by the compiler. Instead, the compiler layer specifies
** an OP_HexBlob opcode, with the hex string representation of
** the blob as P3. This opcode is transformed to an OP_Blob
** the first time it is executed.
*/
case OP_Blob: {
  pTos++;
  assert( pOp->p1 < SQLITE_MAX_LENGTH ); /* Due to SQLITE_MAX_SQL_LENGTH */
  sqlite3VdbeMemSetStr(pTos, pOp->p3, pOp->p1, 0, 0);
  break;
}
#endif /* SQLITE_OMIT_BLOB_LITERAL */

/* Opcode: Variable P1 * *
**
** Push the value of variable P1 onto the stack.  A variable is
** an unknown in the original SQL string as handed to sqlite3_compile().
** Any occurance of the '?' character in the original SQL is considered
** a variable.  Variables in the SQL string are number from left to
** right beginning with 1.  The values of variables are set using the
** sqlite3_bind() API.
*/
case OP_Variable: {
  int j = pOp->p1 - 1;
  Mem *pVar;
  assert( j>=0 && j<p->nVar );

  pVar = &p->aVar[j];
  if( sqlite3VdbeMemTooBig(pVar) ){
    goto too_big;
  }
  pTos++;
  sqlite3VdbeMemShallowCopy(pTos, &p->aVar[j], MEM_Static);
  break;
}

/* Opcode: Pop P1 * *
**

** any element of the stack is NULL, then the result is NULL.
**
** When P1==1, this routine makes a copy of the top stack element
** into memory obtained from sqliteMalloc().
*/
case OP_Concat: {           /* same as TK_CONCAT */
  char *zNew;
  i64 nByte;
  int nField;
  int i, j;
  Mem *pTerm;

  /* Loop through the stack elements to see how long the result will be. */
  nField = pOp->p1 + 2;
  pTerm = &pTos[1-nField];

    }
    pTos++;
    pTos->flags = MEM_Null;
  }else{
    /* Otherwise malloc() space for the result and concatenate all the
    ** stack values.
    */
    if( nByte+2>SQLITE_MAX_LENGTH ){
      goto too_big;
    }
    zNew = sqliteMallocRaw( nByte+2 );
    if( zNew==0 ) goto no_mem;
    j = 0;
    pTerm = &pTos[1-nField];
    for(i=j=0; i<nField; i++, pTerm++){
      int n = pTerm->n;
      assert( pTerm->flags & (MEM_Str|MEM_Blob) );

  }

  /* Copy the result of the function to the top of the stack */
  sqlite3VdbeChangeEncoding(&ctx.s, encoding);
  pTos++;
  pTos->flags = 0;
  sqlite3VdbeMemMove(pTos, &ctx.s);
  if( sqlite3VdbeMemTooBig(pTos) ){
    goto too_big;
  }
  break;
}

/* Opcode: BitAnd * * *
**
** Pop the top two elements from the stack.  Convert both elements
** to integers.  Push back onto the stack the bit-wise AND of the

  }

  /* If payloadSize is 0, then just push a NULL onto the stack. */
  if( payloadSize==0 ){
    assert( pTos->flags==MEM_Null );
    break;
  }
  if( payloadSize>SQLITE_MAX_LENGTH ){
    goto too_big;
  }

  assert( p2<nField );

  /* Read and parse the table header.  Store the results of the parse
  ** into the record header cache fields of the cursor.
  */
  if( pC && pC->cacheStatus==p->cacheCtr ){

  ** corresponding data element (see sqlite3VdbeSerialType()). The
  ** hdr-size field is also a varint which is the offset from the beginning
  ** of the record to data0.
  */
  u8 *zNewRecord;        /* A buffer to hold the data for the new record */
  Mem *pRec;             /* The new record */
  Mem *pRowid = 0;       /* Rowid appended to the new record */
  u64 nData = 0;         /* Number of bytes of data space */
  int nHdr = 0;          /* Number of bytes of header space */
  u64 nByte = 0;         /* Data space required for this record */
  int nZero = 0;         /* Number of zero bytes at the end of the record */
  int nVarint;           /* Number of bytes in a varint */
  u32 serial_type;       /* Type field */
  int containsNull = 0;  /* True if any of the data fields are NULL */
  Mem *pData0;           /* Bottom of the stack */
  int leaveOnStack;      /* If true, leave the entries on the stack */
  int nField;            /* Number of fields in the record */

  /* Add the initial header varint and total the size */
  nHdr += nVarint = sqlite3VarintLen(nHdr);
  if( nVarint<sqlite3VarintLen(nHdr) ){
    nHdr++;
  }
  nByte = nHdr+nData-nZero;
  if( nByte>SQLITE_MAX_LENGTH ){
    goto too_big;
  }

  /* Allocate space for the new record. */
  if( nByte>sizeof(zTemp) ){
    zNewRecord = sqliteMallocRaw(nByte);
    if( !zNewRecord ){
      goto no_mem;
    }

    if( pC->nullRow ){
      pTos->flags = MEM_Null;
      break;
    }else if( pC->isIndex ){
      i64 n64;
      assert( !pC->isTable );
      sqlite3BtreeKeySize(pCrsr, &n64);
      if( n64>SQLITE_MAX_LENGTH ){
        goto too_big;
      }
      n = n64;
    }else{
      sqlite3BtreeDataSize(pCrsr, &n);
    }
    if( n>SQLITE_MAX_LENGTH ){
      goto too_big;
    }
    pTos->n = n;
    if( n<=NBFS ){
      pTos->flags = MEM_Blob | MEM_Short;
      pTos->z = pTos->zShort;
    }else{
      char *z = sqliteMallocRaw( n );
      if( z==0 ) goto no_mem;
      pTos->flags = MEM_Blob | MEM_Dyn;
      pTos->xDel = 0;
      pTos->z = z;
    }
    if( pC->isIndex ){
      rc = sqlite3BtreeKey(pCrsr, 0, n, pTos->z);
    }else{
      rc = sqlite3BtreeData(pCrsr, 0, n, pTos->z);
    }
  }else if( pC->pseudoTable ){
    pTos->n = pC->nData;
    assert( pC->nData<=SQLITE_MAX_LENGTH );
    pTos->z = pC->pData;
    pTos->flags = MEM_Blob|MEM_Ephem;
  }else{
    pTos->flags = MEM_Null;
  }
  pTos->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  break;

  assert( pOp->p1>=0 && pOp->p1<p->nMem );
  pMem = &p->aMem[pOp->p1];
  assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
  rc = sqlite3VdbeMemFinalize(pMem, (FuncDef*)pOp->p3);
  if( rc==SQLITE_ERROR ){
    sqlite3SetString(&p->zErrMsg, sqlite3_value_text(pMem), (char*)0);
  }
  if( sqlite3VdbeMemTooBig(pMem) ){
    goto too_big;
  }
  break;
}


#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/* Opcode: Vacuum * * *
**

    ** dynamic allocation in sContext.s (a Mem struct) is  released.
    */
    sqlite3VdbeChangeEncoding(&sContext.s, encoding);
    pTos++;
    pTos->flags = 0;
    sqlite3VdbeMemMove(pTos, &sContext.s);

    if( sqlite3SafetyOn(db) ){
      goto abort_due_to_misuse;
    }
    if( sqlite3VdbeMemTooBig(pTos) ){
      goto too_big;
    }
  }
  
  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifndef SQLITE_OMIT_VIRTUALTABLE

    /* Sanity checking on the top element of the stack. If the previous
    ** instruction was VNoChange, then the flags field of the top
    ** of the stack is set to 0. This is technically invalid for a memory
    ** cell, so avoid calling MemSanity() in this case.
    */
    if( pTos>=p->aStack && pTos->flags ){
      sqlite3VdbeMemSanity(pTos);
      assert( !sqlite3VdbeMemTooBig(pTos) );
    }
    assert( pc>=-1 && pc<p->nOp );
#ifdef SQLITE_DEBUG

    /* Code for tracing the vdbe stack. */
    if( p->trace && pTos>=p->aStack ){
      int i;

    rc = SQLITE_ERROR;
  }else{
    rc = SQLITE_DONE;
  }
  sqlite3VdbeHalt(p);
  p->pTos = pTos;
  return rc;

  /* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
  ** is encountered.
  */
too_big:
  sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
  rc = SQLITE_TOOBIG;
  goto vdbe_halt;

  /* Jump to here if a malloc() fails.  It's hard to get a malloc()
  ** to fail on a modern VM computer, so this code is untested.
  */
no_mem:
  sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
  rc = SQLITE_NOMEM;

int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
int sqlite3VdbeRecordCompare(void*,int,const void*,int, const void*);
int sqlite3VdbeIdxRowidLen(const u8*);
int sqlite3VdbeExec(Vdbe*);
int sqlite3VdbeList(Vdbe*);
int sqlite3VdbeHalt(Vdbe*);
int sqlite3VdbeChangeEncoding(Mem *, int);
int sqlite3VdbeMemTooBig(Mem*);
int sqlite3VdbeMemCopy(Mem*, const Mem*);
void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
int sqlite3VdbeMemMove(Mem*, Mem*);
int sqlite3VdbeMemNulTerminate(Mem*);
int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
void sqlite3VdbeMemSetInt64(Mem*, i64);
void sqlite3VdbeMemSetDouble(Mem*, double);

*/
void sqlite3VdbeMemSetDouble(Mem *pMem, double val){
  sqlite3VdbeMemRelease(pMem);
  pMem->r = val;
  pMem->flags = MEM_Real;
  pMem->type = SQLITE_FLOAT;
}

/*
** Return true if the Mem object contains a TEXT or BLOB that is
** too large - whose size exceeds SQLITE_MAX_LENGTH.
*/
int sqlite3VdbeMemTooBig(Mem *p){
  if( p->flags & (MEM_Str|MEM_Blob) ){
    int n = p->n;
    if( p->flags & MEM_Zero ){
      n += p->u.i;
    }
    return n>SQLITE_MAX_LENGTH;
  }
  return 0; 
}

/*
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are overwritten.  The pFrom->z field is not duplicated.  If
** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
** and flags gets srcType (either MEM_Ephem or MEM_Static).
*/