SQLite

<li><tt><a href='#default_destructor'>%default_destructor</a></tt>
<li><tt><a href='#default_type'>%default_type</a></tt>
<li><tt><a href='#destructor'>%destructor</a></tt>
<li><tt><a href='#pifdef'>%else</a></tt>
<li><tt><a href='#pifdef'>%endif</a></tt>
<li><tt><a href='#extraarg'>%extra_argument</a></tt>
<li><tt><a href='#pfallback'>%fallback</a></tt>
<li><tt><a href='#reallc'>%free</a></tt>
<li><tt><a href='#pifdef'>%if</a></tt>
<li><tt><a href='#pifdef'>%ifdef</a></tt>
<li><tt><a href='#pifdef'>%ifndef</a></tt>
<li><tt><a href='#pinclude'>%include</a></tt>
<li><tt><a href='#pleft'>%left</a></tt>
<li><tt><a href='#pname'>%name</a></tt>
<li><tt><a href='#pnonassoc'>%nonassoc</a></tt>
<li><tt><a href='#parse_accept'>%parse_accept</a></tt>
<li><tt><a href='#parse_failure'>%parse_failure</a></tt>
<li><tt><a href='#pright'>%right</a></tt>
<li><tt><a href='#reallc'>%realloc</a></tt>
<li><tt><a href='#stack_overflow'>%stack_overflow</a></tt>
<li><tt><a href='#stack_size'>%stack_size</a></tt>
<li><tt><a href='#start_symbol'>%start_symbol</a></tt>
<li><tt><a href='#syntax_error'>%syntax_error</a></tt>
<li><tt><a href='#token'>%token</a></tt>
<li><tt><a href='#token_class'>%token_class</a></tt>
<li><tt><a href='#token_destructor'>%token_destructor</a></tt>

period.  This directive specifies that the identified token should
match any input token.</p>

<p>When the generated parser has the choice of matching an input against
the wildcard token and some other token, the other token is always used.
The wildcard token is only matched if there are no alternatives.</p>

<a id='reallc'></a>
<h4>4.4.26 The <tt>%realloc</tt> and <tt>%free</tt> directives</h4>

<p>The <tt>%realloc</tt> and <tt>%free</tt> directives defines function
that allocate and free heap memory.  The signatures of these functions
should be the same as the realloc() and free() functions from the standard
C library.

<p>If both of these functions are defined
then these functions are used to allocate and free
memory for supplemental parser stack space, if the initial
parse stack space is exceeded.  The initial parser stack size
is specified by either <tt>%stack_size</tt> or the
-DYYSTACKDEPTH compile-time flag.

<a id='errors'></a>
<h2>5.0 Error Processing</h2>

<p>After extensive experimentation over several years, it has been
discovered that the error recovery strategy used by yacc is about
as good as it gets.  And so that is what Lemon uses.</p>

<p>If the parser pops its stack until the stack is empty, and it still
is unable to shift the error symbol, then the
<tt><a href='#parse_failure'>%parse_failure</a></tt> routine
is invoked and the parser resets itself to its start state, ready
to begin parsing a new file.  This is what will happen at the very
first syntax error, of course, if there are no instances of the
"error" non-terminal in your grammar.</p>


<a id='history'></a>
<h2>6.0 History of Lemon</h2>

<p>Lemon was originally written by Richard Hipp sometime in the late
1980s on a Sun4 Workstation using K&amp;R C.  
There was a companion LL(1) parser generator program named "Lime".

** file that specifies the input grammar and actions to take while parsing.
** That input file is processed by Lemon to generate a C-language 
** implementation of a parser for the given grammar.  You might be reading
** this comment as part of the translated C-code.  Edits should be made
** to the original parse.y sources.
*/
}

// Function used to enlarge the parser stack, if needed
%realloc sqlite3_realloc64
%free    sqlite3_free

// All token codes are small integers with #defines that begin with "TK_"
%token_prefix TK_

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.
//

  if( TOKEN.z[0] ){
    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &TOKEN);
  }else{
    sqlite3ErrorMsg(pParse, "incomplete input");
  }
}
%stack_overflow {
  sqlite3OomFault(pParse->db);
}

// The name of the generated procedure that implements the parser
// is as follows:
%name sqlite3Parser

// The following text is included near the beginning of the C source

  execsql {CREATE TABLE t1(x)}
  set sql "INSERT INTO t1 VALUES("
  set tail ""
  for {set i 0} {$i<200} {incr i} {
    append sql "(1+"
    append tail ")"
  }
  append sql 2$tail)
  catchsql $sql
} {0 {}}

# Parser stack overflow is silently ignored when it occurs while parsing the
# schema and PRAGMA writable_schema is turned on.
#
do_test misc5-7.2 {
  sqlite3 db2 :memory:
  sqlite3_db_config db2 DEFENSIVE 0

  char *accept;            /* Code to execute when the parser excepts */
  char *extracode;         /* Code appended to the generated file */
  char *tokendest;         /* Code to execute to destroy token data */
  char *vardest;           /* Code for the default non-terminal destructor */
  char *filename;          /* Name of the input file */
  char *outname;           /* Name of the current output file */
  char *tokenprefix;       /* A prefix added to token names in the .h file */
  char *reallocFunc;       /* Function to use to allocate stack space */
  char *freeFunc;          /* Function to use to free stack space */
  int nconflict;           /* Number of parsing conflicts */
  int nactiontab;          /* Number of entries in the yy_action[] table */
  int nlookaheadtab;       /* Number of entries in yy_lookahead[] */
  int tablesize;           /* Total table size of all tables in bytes */
  int basisflag;           /* Print only basis configurations */
  int printPreprocessed;   /* Show preprocessor output on stdout */
  int has_fallback;        /* True if any %fallback is seen in the grammar */

          psp->insertLineMacro = 0;
        }else if( strcmp(x,"token_type")==0 ){
          psp->declargslot = &(psp->gp->tokentype);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"default_type")==0 ){
          psp->declargslot = &(psp->gp->vartype);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"realloc")==0 ){
          psp->declargslot = &(psp->gp->reallocFunc);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"free")==0 ){
          psp->declargslot = &(psp->gp->freeFunc);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"stack_size")==0 ){
          psp->declargslot = &(psp->gp->stacksize);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"start_symbol")==0 ){
          psp->declargslot = &(psp->gp->start);
          psp->insertLineMacro = 0;
        }else if( strcmp(x,"left")==0 ){

){
  FILE *out, *in, *sql;
  int  lineno;
  struct state *stp;
  struct action *ap;
  struct rule *rp;
  struct acttab *pActtab;
  int i, j, n, sz, mn, mx;
  int nLookAhead;
  int szActionType;     /* sizeof(YYACTIONTYPE) */
  int szCodeType;       /* sizeof(YYCODETYPE)   */
  const char *name;
  int mnTknOfst, mxTknOfst;
  int mnNtOfst, mxNtOfst;
  struct axset *ax;

  }else{
    fprintf(out,"#define %sARG_SDECL\n",name); lineno++;
    fprintf(out,"#define %sARG_PDECL\n",name); lineno++;
    fprintf(out,"#define %sARG_PARAM\n",name); lineno++;
    fprintf(out,"#define %sARG_FETCH\n",name); lineno++;
    fprintf(out,"#define %sARG_STORE\n",name); lineno++;
  }
  if( lemp->reallocFunc ){
    fprintf(out,"#define YYREALLOC %s\n", lemp->reallocFunc); lineno++;
  }else{
    fprintf(out,"#define YYREALLOC realloc\n"); lineno++;
  }
  if( lemp->freeFunc ){
    fprintf(out,"#define YYFREE %s\n", lemp->freeFunc); lineno++;
  }else{
    fprintf(out,"#define YYFREE free\n"); lineno++;
  }
  if( lemp->reallocFunc && lemp->freeFunc ){
    fprintf(out,"#define YYDYNSTACK 1\n"); lineno++;
  }else{
    fprintf(out,"#define YYDYNSTACK 0\n"); lineno++;
  }
  if( lemp->ctx && lemp->ctx[0] ){
    i = lemonStrlen(lemp->ctx);
    while( i>=1 && ISSPACE(lemp->ctx[i-1]) ) i--;
    while( i>=1 && (ISALNUM(lemp->ctx[i-1]) || lemp->ctx[i-1]=='_') ) i--;
    fprintf(out,"#define %sCTX_SDECL %s;\n",name,lemp->ctx);  lineno++;
    fprintf(out,"#define %sCTX_PDECL ,%s\n",name,lemp->ctx);  lineno++;
    fprintf(out,"#define %sCTX_PARAM ,%s\n",name,&lemp->ctx[i]);  lineno++;

  fprintf(out,"#define YY_MAX_SHIFTREDUCE   %d\n", i-1); lineno++;
  fprintf(out,"#define YY_ERROR_ACTION      %d\n", lemp->errAction); lineno++;
  fprintf(out,"#define YY_ACCEPT_ACTION     %d\n", lemp->accAction); lineno++;
  fprintf(out,"#define YY_NO_ACTION         %d\n", lemp->noAction); lineno++;
  fprintf(out,"#define YY_MIN_REDUCE        %d\n", lemp->minReduce); lineno++;
  i = lemp->minReduce + lemp->nrule;
  fprintf(out,"#define YY_MAX_REDUCE        %d\n", i-1); lineno++;

  /* Minimum and maximum token values that have a destructor */
  mn = mx = 0;
  for(i=0; i<lemp->nsymbol; i++){
    struct symbol *sp = lemp->symbols[i];

    if( sp && sp->type!=TERMINAL && sp->destructor ){
      if( mn==0 || sp->index<mn ) mn = sp->index;
      if( sp->index>mx ) mx = sp->index;
    }
  }
  if( lemp->tokendest ) mn = 0;
  if( lemp->vardest ) mx = lemp->nsymbol-1;
  fprintf(out,"#define YY_MIN_DSTRCTR       %d\n", mn);  lineno++;
  fprintf(out,"#define YY_MAX_DSTRCTR       %d\n", mx);  lineno++;    

  tplt_xfer(lemp->name,in,out,&lineno);

  /* Now output the action table and its associates:
  **
  **  yy_action[]        A single table containing all actions.
  **  yy_lookahead[]     A table containing the lookahead for each entry in
  **                     yy_action.  Used to detect hash collisions.

**                       zero the stack is dynamically sized using realloc()
**    ParseARG_SDECL     A static variable declaration for the %extra_argument
**    ParseARG_PDECL     A parameter declaration for the %extra_argument
**    ParseARG_PARAM     Code to pass %extra_argument as a subroutine parameter
**    ParseARG_STORE     Code to store %extra_argument into yypParser
**    ParseARG_FETCH     Code to extract %extra_argument from yypParser
**    ParseCTX_*         As ParseARG_ except for %extra_context
**    YYREALLOC          Name of the realloc() function to use
**    YYFREE             Name of the free() function to use
**    YYDYNSTACK         True if stack space should be extended on heap
**    YYERRORSYMBOL      is the code number of the error symbol.  If not
**                       defined, then do no error processing.
**    YYNSTATE           the combined number of states.
**    YYNRULE            the number of rules in the grammar
**    YYNTOKEN           Number of terminal symbols
**    YY_MAX_SHIFT       Maximum value for shift actions
**    YY_MIN_SHIFTREDUCE Minimum value for shift-reduce actions
**    YY_MAX_SHIFTREDUCE Maximum value for shift-reduce actions
**    YY_ERROR_ACTION    The yy_action[] code for syntax error
**    YY_ACCEPT_ACTION   The yy_action[] code for accept
**    YY_NO_ACTION       The yy_action[] code for no-op
**    YY_MIN_REDUCE      Minimum value for reduce actions
**    YY_MAX_REDUCE      Maximum value for reduce actions
**    YY_MIN_DSTRCTR     Minimum symbol value that has a destructor
**    YY_MAX_DSTRCTR     Maximum symbol value that has a destructor
*/
#ifndef INTERFACE
# define INTERFACE 1
#endif
/************* Begin control #defines *****************************************/
%%
/************* End control #defines *******************************************/
#define YY_NLOOKAHEAD ((int)(sizeof(yy_lookahead)/sizeof(yy_lookahead[0])))

/* Define the yytestcase() macro to be a no-op if is not already defined
** otherwise.
**
** Applications can choose to define yytestcase() in the %include section
** to a macro that can assist in verifying code coverage.  For production
** code the yytestcase() macro should be turned off.  But it is useful
** for testing.
*/
#ifndef yytestcase
# define yytestcase(X)
#endif

/* Macro to determine if stack space has the ability to grow using
** heap memory.
*/
#if YYSTACKDEPTH<=0 || YYDYNSTACK
# define YYGROWABLESTACK 1
#else
# define YYGROWABLESTACK 0
#endif

/* Guarantee a minimum number of initial stack slots.
*/
#if YYSTACKDEPTH<=0
# undef YYSTACKDEPTH
# define YYSTACKDEPTH 2  /* Need a minimum stack size */
#endif


/* Next are the tables used to determine what action to take based on the
** current state and lookahead token.  These tables are used to implement
** functions that take a state number and lookahead value and return an
** action integer.  
**

  int yyhwm;                    /* High-water mark of the stack */
#endif
#ifndef YYNOERRORRECOVERY
  int yyerrcnt;                 /* Shifts left before out of the error */
#endif
  ParseARG_SDECL                /* A place to hold %extra_argument */
  ParseCTX_SDECL                /* A place to hold %extra_context */

  yyStackEntry *yystackEnd;           /* Last entry in the stack */
  yyStackEntry *yystack;              /* The parser stack */
  yyStackEntry yystk0[YYSTACKDEPTH];  /* Initial stack space */




};
typedef struct yyParser yyParser;

#include <assert.h>
#ifndef NDEBUG
#include <stdio.h>
static FILE *yyTraceFILE = 0;

*/
static const char *const yyRuleName[] = {
%%
};
#endif /* NDEBUG */


#if YYGROWABLESTACK
/*
** Try to increase the size of the parser stack.  Return the number
** of errors.  Return 0 on success.
*/
static int yyGrowStack(yyParser *p){
  int oldSize = 1 + (int)(p->yystackEnd - p->yystack);
  int newSize;
  int idx;
  yyStackEntry *pNew;

  newSize = oldSize*2 + 100;
  idx = p->yytos ? (int)(p->yytos - p->yystack) : 0;
  if( p->yystack==p->yystk0 ){
    pNew = YYREALLOC(0, newSize*sizeof(pNew[0]));
    if( pNew==0 ) return 1;
    memcpy(pNew, p->yystack, oldSize*sizeof(pNew[0]));
  }else{
    pNew = YYREALLOC(p->yystack, newSize*sizeof(pNew[0]));
    if( pNew==0 ) return 1;
  }

  p->yystack = pNew;
  p->yytos = &p->yystack[idx];
#ifndef NDEBUG
  if( yyTraceFILE ){
    fprintf(yyTraceFILE,"%sStack grows from %d to %d entries.\n",
            yyTracePrompt, oldSize, newSize);
  }
#endif
  p->yystackEnd = &p->yystack[newSize-1];
  return 0;
}

#endif /* YYGROWABLESTACK */

#if !YYGROWABLESTACK
/* For builds that do no have a growable stack, yyGrowStack always
** returns an error.
*/
# define yyGrowStack(X) 1
#endif

/* Datatype of the argument to the memory allocated passed as the
** second argument to ParseAlloc() below.  This can be changed by
** putting an appropriate #define in the %include section of the input
** grammar.
*/
#ifndef YYMALLOCARGTYPE
# define YYMALLOCARGTYPE size_t
#endif

/* Initialize a new parser that has already been allocated.
*/
void ParseInit(void *yypRawParser ParseCTX_PDECL){
  yyParser *yypParser = (yyParser*)yypRawParser;
  ParseCTX_STORE
#ifdef YYTRACKMAXSTACKDEPTH
  yypParser->yyhwm = 0;
#endif


  yypParser->yystack = yypParser->yystk0;
  yypParser->yystackEnd = &yypParser->yystack[YYSTACKDEPTH-1];





#ifndef YYNOERRORRECOVERY
  yypParser->yyerrcnt = -1;
#endif
  yypParser->yytos = yypParser->yystack;
  yypParser->yystack[0].stateno = 0;
  yypParser->yystack[0].major = 0;



}

#ifndef Parse_ENGINEALWAYSONSTACK
/* 
** This function allocates a new parser.
** The only argument is a pointer to a function which works like
** malloc.

}

/*
** Clear all secondary memory allocations from the parser
*/
void ParseFinalize(void *p){
  yyParser *pParser = (yyParser*)p;

  /* In-lined version of calling yy_pop_parser_stack() for each
  ** element left in the stack */
  yyStackEntry *yytos = pParser->yytos;
  while( yytos>pParser->yystack ){
#ifndef NDEBUG
    if( yyTraceFILE ){
      fprintf(yyTraceFILE,"%sPopping %s\n",
        yyTracePrompt,
        yyTokenName[yytos->major]);
    }
#endif
    if( yytos->major>=YY_MIN_DSTRCTR && yytos->major<=YY_MAX_DSTRCTR ){
      yy_destructor(pParser, yytos->major, &yytos->minor);
    }
    yytos--;
  }

#if YYGROWABLESTACK
  if( pParser->yystack!=pParser->yystk0 ) YYFREE(pParser->yystack);
#endif
}

#ifndef Parse_ENGINEALWAYSONSTACK
/* 
** Deallocate and destroy a parser.  Destructors are called for
** all stack elements before shutting the parser down.

  yypParser->yytos++;
#ifdef YYTRACKMAXSTACKDEPTH
  if( (int)(yypParser->yytos - yypParser->yystack)>yypParser->yyhwm ){
    yypParser->yyhwm++;
    assert( yypParser->yyhwm == (int)(yypParser->yytos - yypParser->yystack) );
  }
#endif


  yytos = yypParser->yytos;




  if( yytos>yypParser->yystackEnd ){
    if( yyGrowStack(yypParser) ){
      yypParser->yytos--;
      yyStackOverflow(yypParser);
      return;
    }
    yytos = yypParser->yytos;
    assert( yytos <= yypParser->yystackEnd );
  }

  if( yyNewState > YY_MAX_SHIFT ){
    yyNewState += YY_MIN_REDUCE - YY_MIN_SHIFTREDUCE;
  }

  yytos->stateno = yyNewState;
  yytos->major = yyMajor;
  yytos->minor.yy0 = yyMinor;
  yyTraceShift(yypParser, yyNewState, "Shift");
}

/* For rule J, yyRuleInfoLhs[J] contains the symbol on the left-hand side

#ifdef YYTRACKMAXSTACKDEPTH
        if( (int)(yypParser->yytos - yypParser->yystack)>yypParser->yyhwm ){
          yypParser->yyhwm++;
          assert( yypParser->yyhwm ==
                  (int)(yypParser->yytos - yypParser->yystack));
        }
#endif

        if( yypParser->yytos>=yypParser->yystackEnd ){





          if( yyGrowStack(yypParser) ){
            yyStackOverflow(yypParser);
            break;
          }
        }

      }
      yyact = yy_reduce(yypParser,yyruleno,yymajor,yyminor ParseCTX_PARAM);
    }else if( yyact <= YY_MAX_SHIFTREDUCE ){
      yy_shift(yypParser,yyact,(YYCODETYPE)yymajor,yyminor);
#ifndef YYNOERRORRECOVERY
      yypParser->yyerrcnt--;
#endif