SQLite

/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"

#if defined(THREADSAFE) && THREADSAFE && defined(__linux__)
#define getpid pthread_self
#endif

/*
** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
** section 6.5.2.2 lines 483 through 490 specify that when a process
** sets or clears a lock, that operation overrides any prior locks set

**
*************************************************************************
** 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 1.130 2004/07/20 14:06:52 drh Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){

trigger_event(A) ::= UPDATE OF inscollist(X). {A.a = TK_UPDATE; A.b = X; }

%type foreach_clause {int}
foreach_clause(A) ::= .                   { A = TK_ROW; }
foreach_clause(A) ::= FOR EACH ROW.       { A = TK_ROW; }
foreach_clause(A) ::= FOR EACH STATEMENT. { A = TK_STATEMENT; }

%type when_clause {Expr*}
when_clause(A) ::= .             { A = 0; }
when_clause(A) ::= WHEN expr(X). { A = X; }

%type trigger_cmd_list {TriggerStep*}
%destructor trigger_cmd_list {sqlite3DeleteTriggerStep($$);}
trigger_cmd_list(A) ::= trigger_cmd(X) SEMI trigger_cmd_list(Y). {
  X->pNext = Y;
  A = X;
}
trigger_cmd_list(A) ::= . { A = 0; }

%type trigger_cmd {TriggerStep*}
%destructor trigger_cmd {sqlite3DeleteTriggerStep($$);}
// UPDATE 
trigger_cmd(A) ::= UPDATE orconf(R) nm(X) SET setlist(Y) where_opt(Z).  
               { A = sqlite3TriggerUpdateStep(&X, Y, Z, R); }

// INSERT
trigger_cmd(A) ::= insert_cmd(R) INTO nm(X) inscollist_opt(F) 

  if( sp->type==TERMINAL ){
    ret = lemp->tokendest!=0;
  }else{
    ret = lemp->vardest!=0 || sp->destructor!=0;
  }
  return ret;
}

/*
** Append text to a dynamically allocated string.  If zText is 0 then
** reset the string to be empty again.  Always return the complete text
** of the string (which is overwritten with each call).
*/
PRIVATE char *append_str(char *zText, int n, int p1, int p2){
  static char *z = 0;
  static int alloced = 0;
  static int used = 0;
  int i, c;
  char zInt[40];

  if( zText==0 ){
    used = 0;
    return z;
  }
  if( n<=0 ) n = strlen(zText);
  if( n+sizeof(zInt)*2+used >= alloced ){
    alloced = n + sizeof(zInt)*2 + used + 200;
    z = realloc(z,  alloced);
  }
  if( z==0 ) return "";
  while( n-- > 0 ){
    c = *(zText++);
    if( c=='%' && zText[0]=='d' ){
      sprintf(zInt, "%d", p1);
      p1 = p2;
      strcpy(&z[used], zInt);
      used += strlen(&z[used]);
      zText++;
      n--;
    }else{
      z[used++] = c;
    }
  }
  z[used] = 0;
  return z;
}

/*
** zCode is a string that is the action associated with a rule.  Expand
** the symbols in this string so that the refer to elements of the parser
** stack.  Return a new string stored in space obtained from malloc.
*/
PRIVATE char *translate_code(struct lemon *lemp, struct rule *rp){
  char *cp, *xp;
  int i;
  char lhsused = 0;    /* True if the LHS element has been used */
  char used[MAXRHS];   /* True for each RHS element which is used */

  for(i=0; i<rp->nrhs; i++) used[i] = 0;
  lhsused = 0;

  append_str(0,0,0,0);
  for(cp=rp->code; *cp; cp++){
    if( isalpha(*cp) && (cp==rp->code || (!isalnum(cp[-1]) && cp[-1]!='_')) ){
      char saved;
      for(xp= &cp[1]; isalnum(*xp) || *xp=='_'; xp++);
      saved = *xp;
      *xp = 0;
      if( rp->lhsalias && strcmp(cp,rp->lhsalias)==0 ){
        append_str("yygotominor.yy%d",-1,rp->lhs->dtnum,0);
        cp = xp;
        lhsused = 1;
      }else{
        for(i=0; i<rp->nrhs; i++){
          if( rp->rhsalias[i] && strcmp(cp,rp->rhsalias[i])==0 ){
            append_str("yymsp[%d].minor.yy%d",-1,
                       i-rp->nrhs+1,rp->rhs[i]->dtnum);
            cp = xp;
            used[i] = 1;
            break;
          }
        }
      }
      *xp = saved;
    }
    append_str(cp, 1, 0, 0);
  } /* End loop */

  /* Check to make sure the LHS has been used */
  if( rp->lhsalias && !lhsused ){
    ErrorMsg(lemp->filename,rp->ruleline,
      "Label \"%s\" for \"%s(%s)\" is never used.",
        rp->lhsalias,rp->lhs->name,rp->lhsalias);
    lemp->errorcnt++;
  }

  /* Generate destructor code for RHS symbols which are not used in the
  ** reduce code */
  for(i=0; i<rp->nrhs; i++){
    if( rp->rhsalias[i] && !used[i] ){
      ErrorMsg(lemp->filename,rp->ruleline,
        "Label %s for \"%s(%s)\" is never used.",
        rp->rhsalias[i],rp->rhs[i]->name,rp->rhsalias[i]);
      lemp->errorcnt++;
    }else if( rp->rhsalias[i]==0 ){
      if( has_destructor(rp->rhs[i],lemp) ){
        append_str("  yy_destructor(%d,&yymsp[%d].minor);\n", -1,
           rp->rhs[i]->index,i-rp->nrhs+1);
      }else{
        /* No destructor defined for this term */
      }
    }
  }
  cp = append_str(0,0,0,0);
  rp->code = Strsafe(cp);
}

/* 
** Generate code which executes when the rule "rp" is reduced.  Write
** the code to "out".  Make sure lineno stays up-to-date.
*/
PRIVATE void emit_code(out,rp,lemp,lineno)
FILE *out;
struct rule *rp;
struct lemon *lemp;
int *lineno;
{
 char *cp;
 int linecnt = 0;







 /* Generate code to do the reduce action */
 if( rp->code ){
   fprintf(out,"#line %d \"%s\"\n{",rp->line,lemp->filename);
   fprintf(out,"%s",rp->code);
   for(cp=rp->code; *cp; cp++){





















     if( *cp=='\n' ) linecnt++;

   } /* End loop */
   (*lineno) += 3 + linecnt;
   fprintf(out,"}\n#line %d \"%s\"\n",*lineno,lemp->outname);
 } /* End if( rp->code ) */




























 return;
}

/*
** Print the definition of the union used for the parser's data stack.
** This union contains fields for every possible data type for tokens
** and nonterminals.  In the process of computing and printing this

      fprintf(out,"      break;\n"); lineno++;
    }
  }
  for(i=0; i<lemp->nsymbol; i++){
    struct symbol *sp = lemp->symbols[i];
    if( sp==0 || sp->type==TERMINAL || sp->destructor==0 ) continue;
    fprintf(out,"    case %d:\n",sp->index); lineno++;

    /* Combine duplicate destructors into a single case */
    for(j=i+1; j<lemp->nsymbol; j++){
      struct symbol *sp2 = lemp->symbols[j];
      if( sp2 && sp2->type!=TERMINAL && sp2->destructor
          && sp2->dtnum==sp->dtnum
          && strcmp(sp->destructor,sp2->destructor)==0 ){
         fprintf(out,"    case %d:\n",sp2->index); lineno++;
         sp2->destructor = 0;
      }
    }

    emit_destructor_code(out,lemp->symbols[i],lemp,&lineno);
    fprintf(out,"      break;\n"); lineno++;
  }
  if( lemp->vardest ){
    struct symbol *dflt_sp = 0;
    for(i=0; i<lemp->nsymbol; i++){
      struct symbol *sp = lemp->symbols[i];

  for(rp=lemp->rule; rp; rp=rp->next){
    fprintf(out,"  { %d, %d },\n",rp->lhs->index,rp->nrhs); lineno++;
  }
  tplt_xfer(lemp->name,in,out,&lineno);

  /* Generate code which execution during each REDUCE action */
  for(rp=lemp->rule; rp; rp=rp->next){
    if( rp->code ) translate_code(lemp, rp);
  }
  for(rp=lemp->rule; rp; rp=rp->next){
    struct rule *rp2;
    if( rp->code==0 ) continue;
    fprintf(out,"      case %d:\n",rp->index); lineno++;
    for(rp2=rp->next; rp2; rp2=rp2->next){
      if( rp2->code==rp->code ){
        fprintf(out,"      case %d:\n",rp2->index); lineno++;
        rp2->code = 0;
      }
    }
    emit_code(out,rp,lemp,&lineno);
    fprintf(out,"        break;\n"); lineno++;
  }
  tplt_xfer(lemp->name,in,out,&lineno);

  /* Generate code which executes if a parse fails */
  tplt_print(out,lemp,lemp->failure,lemp->failureln,&lineno);