SQLite

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.86 2003/01/07 02:47:48 drh Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  sqliteSetString(&pParse->zErrMsg,"syntax error",0);

** TK_DELETE, or TK_INSTEAD.  If the event is of the form
**
**      UPDATE ON (a,b,c)
**
** Then the "b" IdList records the list "a,b,c".
*/
struct TrigEvent { int a; IdList * b; };

} // end %include

// These are extra tokens used by the lexer but never seen by the
// parser.  We put them in a rule so that the parser generator will
// add them to the parse.h output file.
//
%nonassoc END_OF_FILE ILLEGAL SPACE UNCLOSED_STRING COMMENT FUNCTION
          COLUMN AGG_FUNCTION.

*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.53 2003/01/07 02:47:48 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <stdlib.h>

/*

        }
        break;
      }
      case TK_ILLEGAL: {
        sqliteSetNString(pzErrMsg, "unrecognized token: \"", -1, 
           pParse->sLastToken.z, pParse->sLastToken.n, "\"", 1, 0);
        nErr++;
        goto abort_parse;
      }
      default: {
        sqliteParser(pEngine, tokenType, pParse->sLastToken, pParse);
        if( pParse->zErrMsg && pParse->sErrToken.z ){
          sqliteSetNString(pzErrMsg, "near \"", -1, 
             pParse->sErrToken.z, pParse->sErrToken.n,
             "\": ", -1,

**
** 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 1.192 2003/01/07 02:47:48 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The makefile scans this source file and creates the following
** array of string constants which are the names of all VDBE opcodes.

  unsigned long long int x;
  __asm__("rdtsc\n\t"
          "mov %%edx, %%ecx\n\t"
          :"=A" (x));
  return x;
}
#endif

/*
** The CHECK_FOR_INTERRUPT macro defined here looks to see if the
** sqlite_interrupt() routine has been called.  If it has been, then
** processing of the VDBE program is interrupted.
**
** This macro added to every instruction that does a jump in order to
** implement a loop.  This test used to be on every single instruction,
** but that meant we more testing that we needed.  By only testing the
** flag on jump instructions, we get a (small) speed improvement.
*/
#define CHECK_FOR_INTERRUPT \
   if( db->flags & SQLITE_Interrupt ) goto abort_due_to_interrupt;


/*
** Execute the program in the VDBE.
**
** If an error occurs, an error message is written to memory obtained
** from sqliteMalloc() and *pzErrMsg is made to point to that memory.
** The return parameter is the number of errors.

  /* No instruction ever pushes more than a single element onto the
  ** stack.  And the stack never grows on successive executions of the
  ** same loop.  So the total number of instructions is an upper bound
  ** on the maximum stack depth required.
  **
  ** Allocation all the stack space we will ever need.
  */
  sqliteVdbeAddOp(p, OP_Halt, 0, 0);
  zStack = p->zStack = sqliteMalloc( p->nOp*sizeof(zStack[0]) );
  aStack = p->aStack = sqliteMalloc( p->nOp*sizeof(aStack[0]) );
  p->tos = -1;
#ifdef VDBE_PROFILE
  {
    int i;
    for(i=0; i<p->nOp; i++){

  rc = SQLITE_OK;
#ifdef MEMORY_DEBUG
  if( access("vdbe_trace",0)==0 ){
    p->trace = stdout;
  }
#endif
  if( sqlite_malloc_failed ) goto no_mem;
  for(pc=0; rc==SQLITE_OK; pc++){
    assert( pc>=0 && pc<p->nOp );
#ifdef VDBE_PROFILE
    origPc = pc;
    start = hwtime();
#endif
    pOp = &p->aOp[pc];














    /* Only allow tracing if NDEBUG is not defined.
    */
#ifndef NDEBUG
    if( p->trace ){
      vdbePrintOp(p->trace, pc, pOp);
    }
#endif

**
** An unconditional jump to address P2.
** The next instruction executed will be 
** the one at index P2 from the beginning of
** the program.
*/
case OP_Goto: {
  CHECK_FOR_INTERRUPT;
  pc = pOp->p2 - 1;
  break;
}

/* Opcode:  Gosub * P2 *
**
** Push the current address plus 1 onto the return address stack

    errorAction = pOp->p2;
    if( pOp->p3 ){
	sqliteSetString(pzErrMsg, pOp->p3, 0);
	goto cleanup;
    }
    goto abort_due_to_error;
  }else{
    goto cleanup;
  }

}

/* Opcode: Integer P1 * P3
**
** The integer value P1 is pushed onto the stack.  If P3 is not zero
** then it is assumed to be a string representation of the same integer.
*/

    sqliteBtreeKeySize(pCrsr, &amt);
    if( amt<=0 ){
      rc = SQLITE_CORRUPT;
      goto abort_due_to_error;
    }
    if( amt>NBFS ){
      z = sqliteMallocRaw( amt );
      if( z==0 ) goto no_mem;
      aStack[tos].flags = STK_Str | STK_Dyn;
    }else{
      z = aStack[tos].z;
      aStack[tos].flags = STK_Str;
    }
    sqliteBtreeKey(pCrsr, 0, amt, z);
    zStack[tos] = z;

** jump immediately to P2.
*/
case OP_Prev:
case OP_Next: {
  Cursor *pC;
  BtCursor *pCrsr;

  CHECK_FOR_INTERRUPT;
  if( VERIFY( pOp->p1>=0 && pOp->p1<p->nCursor && ) 
      (pCrsr = (pC = &p->aCsr[pOp->p1])->pCursor)!=0 ){
    int res;
    if( pC->nullRow ){
      res = 1;
    }else{
      rc = pOp->opcode==OP_Next ? sqliteBtreeNext(pCrsr, &res) :

  int j;
  HashElem *i;
  char *z;

  VERIFY( if( iSet<0 || iSet>=p->nSet ) goto bad_instruction; )
  pSet = &p->aSet[iSet];
  nRoot = sqliteHashCount(&pSet->hash);
  aRoot = sqliteMallocRaw( sizeof(int)*(nRoot+1) );
  if( aRoot==0 ) goto no_mem;
  for(j=0, i=sqliteHashFirst(&pSet->hash); i; i=sqliteHashNext(i), j++){
    toInt((char*)sqliteHashKey(i), &aRoot[j]);
  }
  aRoot[j] = 0;
  z = sqliteBtreeIntegrityCheck(pOp->p2 ? db->pBeTemp : pBt, aRoot, nRoot);
  if( z==0 || z[0]==0 ){
    if( z ) sqliteFree(z);

**
** Attempt to read an integer from the temporary storage buffer
** and push it onto the stack.  If the storage buffer is empty, 
** push nothing but instead jump to P2.
*/
case OP_ListRead: {
  Keylist *pKeylist;
  CHECK_FOR_INTERRUPT;
  pKeylist = p->pList;
  if( pKeylist!=0 ){
    VERIFY(
      if( pKeylist->nRead<0 
        || pKeylist->nRead>=pKeylist->nUsed
        || pKeylist->nRead>=pKeylist->nKey ) goto bad_instruction;
    )

** opcode. The list is empty after this is executed.
*/
case OP_ListPush: {
  p->keylistStackDepth++;
  assert(p->keylistStackDepth > 0);
  p->keylistStack = sqliteRealloc(p->keylistStack, 
          sizeof(Keylist *) * p->keylistStackDepth);
  if( p->keylistStack==0 ) goto no_mem;
  p->keylistStack[p->keylistStackDepth - 1] = p->pList;
  p->pList = 0;
  break;
}

/* Opcode: ListPop * * * 
**

** Push the data for the topmost element in the sorter onto the
** stack, then remove the element from the sorter.  If the sorter
** is empty, push nothing on the stack and instead jump immediately 
** to instruction P2.
*/
case OP_SortNext: {
  Sorter *pSorter = p->pSort;
  CHECK_FOR_INTERRUPT;
  if( pSorter!=0 ){
    p->pSort = pSorter->pNext;
    p->tos++;
    zStack[p->tos] = pSorter->pData;
    aStack[p->tos].n = pSorter->nData;
    aStack[p->tos].flags = STK_Str|STK_Dyn;
    sqliteFree(pSorter->zKey);

** Input ends if a line consists of just "\.".  A field containing only
** "\N" is a null field.  The backslash \ character can be used be used
** to escape newlines or the delimiter.
*/
case OP_FileRead: {
  int n, eol, nField, i, c, nDelim;
  char *zDelim, *z;
  CHECK_FOR_INTERRUPT;
  if( p->pFile==0 ) goto fileread_jump;
  nField = pOp->p1;
  if( nField<=0 ) goto fileread_jump;
  if( nField!=p->nField || p->azField==0 ){
    char **azField = sqliteRealloc(p->azField, sizeof(char*)*nField+1);
    if( azField==0 ){ goto no_mem; }
    p->azField = azField;

** Reset the aggregator so that it no longer contains any data.
** Future aggregator elements will contain P2 values each.
*/
case OP_AggReset: {
  AggReset(&p->agg);
  p->agg.nMem = pOp->p2;
  p->agg.apFunc = sqliteMalloc( p->agg.nMem*sizeof(p->agg.apFunc[0]) );
  if( p->agg.apFunc==0 ) goto no_mem;
  break;
}

/* Opcode: AggInit * P2 P3
**
** Initialize the function parameters for an aggregate function.
** The aggregate will operate out of aggregate column P2.

** The order of aggregator opcodes is important.  The order is:
** AggReset AggFocus AggNext.  In other words, you must execute
** AggReset first, then zero or more AggFocus operations, then
** zero or more AggNext operations.  You must not execute an AggFocus
** in between an AggNext and an AggReset.
*/
case OP_AggNext: {
  CHECK_FOR_INTERRUPT;
  if( p->agg.pSearch==0 ){
    p->agg.pSearch = sqliteHashFirst(&p->agg.hash);
  }else{
    p->agg.pSearch = sqliteHashNext(p->agg.pSearch);
  }
  if( p->agg.pSearch==0 ){
    pc = pOp->p2 - 1;

** are no more elements in the set, do not do the push and fall through.
** Otherwise, jump to P2 after pushing the next set element.
*/
case OP_SetFirst: 
case OP_SetNext: {
  Set *pSet;
  int tos;
  CHECK_FOR_INTERRUPT;
  if( pOp->p1<0 || pOp->p1>=p->nSet ){
    if( pOp->opcode==OP_SetFirst ) pc = pOp->p2 - 1;
    break;
  }
  pSet = &p->aSet[pOp->p1];
  if( pOp->opcode==OP_SetFirst ){
    pSet->prev = sqliteHashFirst(&pSet->hash);

  /* Jump to here for any other kind of fatal error.  The "rc" variable
  ** should hold the error number.
  */
abort_due_to_error:
  sqliteSetString(pzErrMsg, sqlite_error_string(rc), 0);
  goto cleanup;

  /* Jump to here if the sqlite_interrupt() API sets the interrupt
  ** flag.
  */
abort_due_to_interrupt:
  assert( db->flags & SQLITE_Interrupt );
  db->flags &= ~SQLITE_Interrupt;
  if( db->magic!=SQLITE_MAGIC_BUSY ){
    rc = SQLITE_MISUSE;
  }else{
    rc = SQLITE_INTERRUPT;
  }
  sqliteSetString(pzErrMsg, sqlite_error_string(rc), 0);
  goto cleanup;

  /* Jump to here if a operator is encountered that requires more stack
  ** operands than are currently available on the stack.
  */
not_enough_stack:
  sprintf(zBuf,"%d",pc);
  sqliteSetString(pzErrMsg, "too few operands on stack at ", zBuf, 0);
  rc = SQLITE_INTERNAL;


  /* Jump here if an illegal or illformed instruction is executed.
  */
VERIFY(
bad_instruction:
  sprintf(zBuf,"%d",pc);
  sqliteSetString(pzErrMsg, "illegal operation at ", zBuf, 0);
  rc = SQLITE_INTERNAL;
  goto cleanup;
)
}